ML050060080

Annual Operating Report for the Penn State Breazeale Reactor (Psbr)

ML050060080
Person / Time
Site:	Pennsylvania State University
Issue date:	12/16/2004
From:	Sears C Pennsylvania State Univ
To:	Document Control Desk, Office of Nuclear Reactor Regulation
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Download: ML050060080 (132)

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(814) 865-6351 PENN STATE FAX: (814) 863-4840 College of Engineering Breazeale Nuclear Reactor Building Wm1 Radiation Science and Engineering Center The Pennsylvania State University Qw University Park, PA 16802-2301 Annual Operating Report, FY 03-04 PSBR Technical Specifications 6.6.1 License R-2, Docket No. 50-5 December 16,2004 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D. C. 20555

Dear Sir:

Enclosed please find the Annual Operating Report for the Penn State Breazeale Reactor (PSBR). This report covers the period from July 1, 2003 through June 30, 2004, as required by technical specifications requirement 6.6.1. Also included are any changes applicable to 10 CFR 50.59.

A copy of the Forty-Ninth Annual Progress Report of the Penn State Radiation Science and Engineering Center is included as supplementary information.

Sincerely yours, Q C. Frederick Sears Director, Radiation Science and Engineering Center Enclosures tlf cc. E. J. Pell D. N. Wormley L. C. Burton E. J. Boeldt M. Mendonca T. Dragoun C)01 An Equal Opportunity University

PENN STATE BREAZEALE REACTOR Annual Operating Report, FY 03-04 PSBR Technical Specifications 6.6.1 License R-2, Docket No. 50-5 Reactor Utilization The Penn State Breazeale Reactor (PSBR) is a TRIGA Mark III facility capable of 1 MW steady state operation, and 2000 MW peak power pulsing operation. Utilization of the reactor and its associated facilities falls into two major categories:

EDUCATION utilization is primarily in the form of laboratory classes conducted for graduate and undergraduate students and numerous high school science groups. These classes vary from neutron activation analysis of an unknown sample to the calibration of a reactor control rod. In addition, an average of 2500 visitors tour the PSBR facility each year.

RESEARCHISERVICE accounts for a large portion of reactor time which involves Radionuclear Applications, Neutron Radiography, a myriad of research programs by faculty and graduate students throughout the University, and various applications by the industrial sector.

The PSBR facility operates on an 8 AM - 5 PM shift, five days a week, with an occasional 7 AM - 7 PM or 8 AM - 12 Midnight shift to accommodate laboratory courses or research/service projects.

Summary of Reactor Operating Experience - Tech Specs requirement 6.6.1.a.

Between July 1,2003 and June 30,2004, the PSBR was critical for 1070 hours0.0124 days <br />0.297 hours <br />0.00177 weeks <br />4.07135e-4 months <br /> or 3.9 hrs/shift subcritical for 417 hours0.00483 days <br />0.116 hours <br />6.894841e-4 weeks <br />1.586685e-4 months <br /> or 1.5 hrs/shift used while shutdown for 657 hours0.0076 days <br />0.183 hours <br />0.00109 weeks <br />2.499885e-4 months <br /> or 2.4 hrs/shift not available 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> or 0.0 hrs/shift Total usage 2155 hours0.0249 days <br />0.599 hours <br />0.00356 weeks <br />8.199775e-4 months <br /> or 7.9 hrs/shift The reactor was pulsed a total of 116 times with the following reactivities:

< $2.00 11

$2.00 to $2.50 96

> $2.50 9 The square wave mode of operation was used 62 times to power levels between 100 and 500 KW.

Total energy produced during this report period was 736 MWH with a consumption of 38 grams of U-235.

Unscheduled Shutdowns - Tech Specs requirement 6.6.1.b.

The five unplanned shutdowns during the July 1, 2003 to June 30, 2004 period are described below.

On August 8, 2003, a Watchdog Scram occurred while at 900 kW during a run against the fast neutron irradiator. The operator had noted a downward spike in power and went to the special screen to print out the event. He hit "print screen" and then realized he needed to freeze the screen first. He hit "freeze" and then hit "print screen" again. The watchdog scram occurred in about 30 seconds. Hitting the "print screen" twice in close succession caused an overload of the 1

PSBR Annual Operating Report, FY 03-04 CPU of the DCC-X control computer. The event was duplicated at shutdown. This software defect had already been identified by AECL as a software change request and was fixed in the console software upgrade of August 2004.

On September 26, 2003, during operation in 3-rod auto mode at 800 kW, the reactor operator observed that the shim and regulating rods were adjusting to xenon changes but that the safety rod was remaining fixed in position. Manually moving the transient rod would cause the shim and regulating rods to move in response, but again the safety rod remained fixed in position. The control system was then put into manual mode and attempts to move the safety rod were unsuccessful. The transient, shim and regulating rods were then moved to their lower limits shutting down the reactor. The safety rod was then scrammed from its position to verify that its scram function was operable. Even though the safety rod could not be moved by its rod drive, the Tech Spec was not violated since the Tech Spec requirement is for three rods to be operable.

AP-13, Maintenance/Repair, was initiated. The investigation revealed that the pinion drive had drag on the center mounting plate. The center was machined but there was still drag of the armature rubbing against the inside of the mounting plate. This rubbing had been taking place over time and had galled the surface. The mounting plate was again machined to fix this problem.

Following re-assembly and testing of the rod drive and motor, CCP- 1 was performed to measure rod drive times and rod drop time which were satisfactory.

On October 7, 2003, the reactor operator tripped the reactor during operation at 750 kW upon receipt of a building fire alarm. The building was evacuated. An investigation revealed that a mechanical contractor grinding concrete in the Cobalt-60 facility basement created excess dust that caused the smoke detector to initiate an alarm. During earlier contractor work, the smoke detector had been bagged and bypassed, but had been returned to normal service following the initial work.

On November 3,2003, during square wave operation at 84 kW, the DCC-Z monitoring computer froze during an attempt to print the square wave data. The printer did not respond to the first print screen command and was found to be jammed. The jam was cleared and then a second print screen caused the DCC-Z shutdown. The operator then shut down the reactor. This was similar to the event of August 8, 2003 on DCC-X. Pressing the "print screen" twice in close succession can cause an overload of the computer CPU. This software defect had previously been identified by AECL as a software change request and was fixed in the console software upgrade of August 2004.

On January 7, 2004, a reactor trip occurred approximately 30 seconds after reaching 800 kW when a Wide Range RSS (reactor safety system) "Fission Chamber Detector Voltage Low" scram occurred. AP-4, Event Evaluation, and AP-13, Maintenance/Repair, procedures were initiated. No conclusions could be reached during troubleshooting of the Wide Range pre-amp and high voltage supply. However, as a precautionary measure both components were replaced.

CCP-7, Wide Range Channel Electronic Checks, was then completed. Following CCP-7, the reactor was taken to 1 MW in steps to confirm Wide Range channel and fuel temperature channel indications against previous data; the comparison of operating data indicated a conservative operation. Normal operations were resumed.

Major Maintenance With Safety Significance - Tech Specs requirement 6.6.1.c.

No major preventative or corrective maintenance operations with safety significance have been performed during this reporting period.

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PSBR Annual Operating Report, FY 03-04 Major Changes Reportable Under 10 CFR 50.59 - Tech Specs requirement 6.6.1 .d.

Facility Changes -

On April 15, 2004, the DCC-X CRT monitor was replaced with an LCD monitor. A screening found no applicability under 50.59. The DCC-X monitor provides no safety function and provides monitoring only.

Procedures -

Procedures are normally reviewed biennially, and on an as needed basis. Changes during the year were numerous and no attempt will be made to list them.

New Tests and Experiments -

None Radioactive Effluents Released - Tech Specs requirement 6.6.1 .e.

Liquid There were no planned liquid effluent releases under the reactor license for the report period Liquid radioactive waste from the radioisotope laboratories at the PSBR is under the University byproduct materials license and is transferred to the Radiation Protection Office for disposal with the waste from other campus laboratories. Liquid waste disposal techniques include storage for decay, release to the sanitary sewer as per 10 CFR 20, and solidification for shipment to licensed disposal sites.

Gaseous Gaseous effluent Ar-41 is released from dissolved air in the reactor pool water, air in dry irradiation tubes, air in neutron beam ports, and air leakage to and from the carbon-dioxide purged pneumatic sample transfer system.

The amount of Ar-41 released from the reactor pool is very dependent upon the operating power level and the length of time at power. The release per MWH is highest for extended high power runs and lowest for intermittent low power runs. The concentration of Ar-41 in the reactor bay and the bay exhaust was measured by the Radiation Protection staff during the summer of 1986.

Measurements were made for conditions of low and high power runs simulating typical operating cycles. Based on these measurements, an annual release of between 558 mCi and 1693 mCi of Ar-41 is calculated for July 1, 2003 to June 30, 2004, resulting in an average concentration at ground level outside the reactor building that is 0.9 % to 2.7 % of the effluent concentration limit in Appendix B to 10 CFR 20.1001 - 20.2402. The concentration at ground level is estimated using only dilution by a I m/s wind into the lee of the 200 m2 cross section of the reactor bay.

During the report period, several irradiation tubes were used at high enough power levels and for long enough runs to produce significant amounts of Ar-41. The calculated annual production was 343 mCi. Since this production occurred in a stagnant volume of air confined by close fitting shield plugs, much of the Ar-41 decayed in place before being released to the reactor bay. The reported releases from dissolved air in the reactor pool are based on measurements made, in part, when a dry irradiation tube was in use at high power levels; some of the Ar-41 releases from the tubes are part of rather than in addition to the release figures quoted in the previous paragraph.

Even if all of the 343 mCi were treated as a separate release, the percent of the Appendix B limit given in the previous paragraph would still be no more than 3.3 %.

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PSBR Annual Operating Report, FY 03-04 Production and release of Ar-41 from reactor neutron beam ports was minimal. Beam port #7 has only three small (1/2 inch diameter) collimation tubes exiting the port and any Ar-41 production in these small tubes is negligible. Beam port #4 has an aluminum cap installed inside the outer end of the beam tube to prevent air movement into or out of the tube as the beam port door is opened or closed. The estimated Ar-41 production in beam port #4 for all beam port operations is 68 mCi. With the aforementioned aluminum cap in place, it is assumed that this Ar-41 decayed in place. Radiation Protection Office air measurements have found no presence of Ar-41 with the beam port cap in place.

The use of the pneumatic transfer system was minimal during this period and any Ar-41 release would be insignificant since the system operates with CO-2 as the fill gas.

Tritium release from the reactor pool is another gaseous release. The evaporation rate of the reactor pool was checked previously by measuring the loss of water from a flat plastic dish floating in the pool. The dish had a surface area of 0.38 ft2 and showed a loss of 139.7 grams of water over a 71.9 hour1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br /> period giving a loss rate of 5.11 g ft- 2 hr-1 . Based on a pool area of about 395 ft 2 the annual evaporation rate would be 4680 gallons. This is of course dependent upon relative humidity, temperature of air and water, air movement, etc. For a pool 3 H concentration of 37094 pCi/l (the average for July 1,2003 to June 30,2004) the tritium activity released from the ventilation system would be 657 [LCi. A dilution factor of 2 x 108 ml s-I was used to calculate the unrestricted area concentration. This is from 200 m2 (cross-section of the building) times 1 m s-I (wind velocity). These are the values used in the safety analysis in the reactor license. A sample of air conditioner condensate a previous year showed no detectable 3 H. Thus, there is probably very little 3 H recycled into the pool by way of the air conditioner condensate and all evaporation can be assumed to be released.

3 H released 657 ItC Average concentration, unrestricted area 1.04 x 10-13 [ECi/ml Permissible concentration, unrestricted area 1 x 10-7 VCi/ml Percentage of permissible concentration 1.04 x 10 -4 %

Calculated effective dose, unrestricted area 5.21 x 10-5 mRem Environmental Surveys - Tech Specs requirement 6.6.1 .f.

The only environmental surveys performed were the routine TLD gamma-ray dose measurements at the facility fence line and at control points in two residential areas several miles away. This reporting year's measurements (in millirems) tabulated below represent the July 1, 2003 to June 30, 2004 period.

3rd Otr '03 4th Otr '03 1st Otr '04 2nd Otr '04 Total Fence North 26.0 28.8 21.5 29.3 105.6 Fence South 25.0 28.4 22.3 30.7 106.4 Fence East 26.6 29.3 23.1 25.3 104.3 Fence West 23.5 28.6 21.3 28.9 102.3 Control 23.0 27.6 20.5 23.2 94.3 Control 22.2 23.2 19.0 21.6 86.0 Personnel Exposures - Tech Specs requirement 6.6.1 .g.

No reactor personnel or visitors received an effective dose equivalent in excess of 10% of the permissible limits under 10 CFR 20.

4 LAST PAGE

PENN STATE UNIVERSITY Radiation Science & Engineering Center thA u 9

49t Annuial- Progress Report College of Engineering

-BreazealeNuclear Reactor University Park, PA

- December 2004 PENNSTATE Vnr

49TIl ANNUAL PROGRESS REPORT PENN STATE RADIATION SCIENCE

& ENGINEERING CENTER July 1, 2003 to June 30, 2004 Submitted to:

United States Department of Energy and Penn State By:

C. Frederick Sears (Director)

Kenan Onlu (Associate Director for Research)

Terry L. Flinchbaugh (Associate Director for Operations)

Angela D. Pope (Staff Assistant, Editor)

Radiation Science and Engineering Center Penn State University Park, PA 16802 December 2004 Contract DE-AC07-99ID1 3727 Contract 0036822 U.Ed. ENG 05-63 Penn State is committed to affirmative action, equal opportunity, and the diversity of its workforce.

TABLE OF CONTENTS Page PREFACE - T.L. Flinchbaugh iv

1. INTRODUCTION - K. JnlIu 1 II. PERSONNEL - T.L. Flinchbaugh 4 III. REACTOR OPERATIONS - T.L. Flinchbaugh 8 IV. GAMMA IRRADIATION FACILITY - C.C. Davison 12 V. EDUCATION AND TRAINING - C.C. Davison 17 VI. NEUTRON BEAM LABORATORY - K. Onlu 20 VII. RADIONUCLEAR APPLICATIONS LABORATORY A. Service - T.H. Daubenspeck 23 v B. Research -K. Onlu 24 VIII. PATHFINDER FUEL SHIPMENT - G.M. Morlang 25 IX. LOW PRESSURE INTEGRAL TEST FACILITY - L.E. Hochreiter, S.M. Cetiner 27 I X. ANGULAR CORRELATIONS LABORATORY - G.L. Catchen 39 XI. ENVIRONMENTAL HEALTH AND SAFETY - D.Bertocchi 40 XII. RADIATION SCIENCE AND ENGINEERING CENTER RESEARCH AND SERVICE UTILIZATION A. Penn State Research and Service Utilizing the Facilities of the Penn State 42 Radiation Science & Engineering Center - A.D. Pope B. Other Universitites, Organizations and Companies Utilizing the Facilities of 73 the Penn State Radiation Science & Engineering Center - T.L. Flinchbaugh XIII. PUBLICATIONS - A.D. Pope 97 APPENDIX A. Faculty, Staff, Students, and Industries Utilizing the Facilities of the 101 Penn State Radiation Science & Engineering Center - T.L. Flinchbaugh APPENDIX B. Formal Tour Groups - A.D. Pope 104 ii

TABLE OF CONTENTS TABLES Page

1. Personnel 5

2. Penn State Reactor Safeguards Committee 6

3. Reactor Operation Data 10

4. Reactor Utilization Data 11

5. Summary of Current Gamma Irradiation Facilities 14

6. Cobalt-60 Utilization Data 14

7. Academic Instruction Data 19 FIGURES Page

1. Organization Chart 7

2. Gamma Facility Irradiation Usage 15

3. Gamma Irradiation Uses and Examples 16

4. Educational Institutions Visiting the RSEC 20 iii

PREFACE Administrative responsibility for the Radiation Science and Engineering Center (RSEC) resides in the College of Engineering. Overall responsibility for the reactor license resides with the Vice President for Research and the Dean of the Graduate School. The reactor and associated laboratories are available to all Penn State colleges for education and research programs. In addition, the facility is made available to assist other educational institutions, government agencies and industries having common and compatible needs and objectives, providing services that are essential in meeting research, development, education, and training needs.

The Penn State University Radiation Science and Engineering Center's 49th Annual Progress Report (July 2003 through June 2004) is submitted in accordance with the requirements of Contract DE-AC07-991D13727 between the United States Department of Energy and Bechtel (BWXT Idaho), and their Contract 00036822 with The Pennsylvania State University. This report also provides the University administration with a summary ofthe utilization ofthe facility forthe past year.

Numerous individuals are to be recognized and thanked for their dedication and commitment in this report, especially Angela Pope who edited the report. Special thanks are extended to those responsible for the individual sections as listed in the table of contents and to the individual facility users whose research summaries are compiled in Section XII.

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INTROD UCTION INTRODUCTION MISSION

• During this fiscal year the lobby was expanded and is now fully functional. The new lobby provides 400 square feet of additional space to handle the visitors The mission of The Penn State Radiation Science and and students. A common room for staff for copying, Engineering Center (RSEC), in partnership with faculty, storage, kitchenette facilities and related staff, students, alumni, government, and corporate administrative tasks was added. All of the new areas leaders, is to safely utilize nuclear technology to benefit are ergonomically designed with modem furnishings.

society through education, research, and service. The exterior of the lobby was designed to be aesthetically pleasing yet provide maximum security.

The RSEC facilities have a diverse and dedicated staff The entire project was unique in that it had to be with a commitment to safety, excellence, quality, user accomplished while maintaining building integrity and satisfaction, and education by example and teaching. reactor facility containment during all phases of construction. The project was completed in a period of only 13 weeks.

VISION It is the vision of the faculty and staff of the Radiation Science and Engineering Center to become a leading national resource and make significant contributions in the following areas:

Safety-Actively promote nuclear and personal safety in everything we do.

Education-Develop and deliver innovative educational programs to advance societal knowledge of nuclear science and engineering through resident instruction and continuing education for students of all ages and their educators.

Research-Expand leading edge research that increases fundamental knowledge of nuclear science and engineering particularly in the area of materials research applications of nuclear techniques.

Service-Expand and build a diverse array of services and users by maintaining excellence, quality, user satisfaction, and efficient service to supplement university funding and enhance education and research.

In conducting this mission in pursuit of the stated vision, the following activities are highlighted among the numerous accomplishments reported in the pages that follow:

I

• Architectural plans for the RSEC expansion for a new

• Mini-grants were awarded on a competitive basis Neutron Beam Hall and Neutron Beam Ports facilities to Penn State and non-Penn State individuals are completed. Working with a professional submitting proposals to use the Penn State architectural firm, a contractor, and related personnel Radiation Science and Engineering Center from various university functions, we obtained a firm facilities.

estimate for the expansion cost. Internal benefactors of the new neutron beam facilities are identified. We obtained support letters or expression of interests . Efforts continue to lay the groundwork for the from about 30 faculty members from four different development of a cold neutron beam and new colleges within the university. More than half of the neutron beam port facilities. Both thermal and total budget for expansion is currently available, and thermo-hydraulic behavior of two University efforts to raise the remaining portion of budget based cold neutron sources are being evaluated continue. in order to build a third generation mesitylene based cold neutron source at Penn State. Code development also continues to model the existing

• Considerable faculty and staff effort was rewarded beam ports and various future designs.

when DOE issued the INIE (Innovations in Nuclear Infrastructure and Education) grants. The INIE Big-Ten Consortium, led by Penn State and comprised of

• Dr. Kenan OnMl, and Drs. Vijaykrisnan Penn State, Purdue University, the University of Narayanan and Mary Jane Irwin of the Illinois and the University of Wisconsin received Department of Computer Science and approximately $1.97 million per year in FY02 and Engineering continue testing of neutron FY03. The Ohio State University and the University induced soft errors in semiconductor of Michigan joined the Big-Ten Consortium during memories and started to develop a soft error this fiscal year and the consortium funding was analysis toolset program.

increased to $ 2.1 million per year. Currently, DOE plans to continue the grant program for at least three additional years. The objective of the INIE program

• Drs. Jack Brenizer, Matthew Mench, Kenan is to strengthen the nation's university nuclear OnIU, and Abel Chuang of the Department of engineering programs through innovative use of the Mechanical and Nuclear Engineering continue university research and training reactors. During the major research projects using neutron two-year period of the INIE grant the following was radioscopy and neutron radiography for accomplished at Penn State - investigation of fuel cells for several major automotive companies. Several other

• The Room 2 laboratory/classroom was totally companies used the beam facilities for refurbished and equipped with state of the art radiography and radioscopy projects, some of computer work stations and audio-visual which were associated with NASA's space equipment.

shuttle program.

• A refurbished GammaCell was purchased, and

• Dr. Kenan Onlo, and Dr. Peter 1.Kuniholm from installed during the '02-'03 fiscal year. The Cornell University continue neutron activation upgraded Cobalt-60 loading decreased irradiation analysis of absolutely dated tree rings to times by a factor of ten, providing much better identify climatically significant marker events service for campus users.

in history and prehistory.

• A slow neutron chopper system was developed

• The project to upgrade the reactor control system with a chopper brought from the Cornell hardware and software continued during the year.

University, Ward Center for Nuclear Sciences to (Installation and all necessary testing of the new characterize the neutron beam used for system was completed in the new fiscal year.)

radiography and radioscopy. As part of the INIE grant, this system is available for loan to other research reactors. As part of neutron beam

. The neutron irradiation of semi-conductors for characterization efforts, a He-3 neutron commercial, military, and space applications spectrometer system was ordered to determine continued at a very healthy pace.

the spectrum of high-energy neutrons.

2

. The use of neutron radioscopy and neutron transmission as a research and service tool to industry continued at a very high level during the year with increasing interest by companies who fabricate boron containing metals used in the nuclear industry. Efforts are under way to upgrade the software and hardware associated with this wvork.

. Income from service work done for industrial users was used to continue the support of three Ph.D.

graduate students in the nuclear engineering program.

Two students are working in the area of modeling the Penn State TRIGA reactor core and developing better computer code tools for fuel depletion tracking and core loading designs. The third student completed work in the area of thermal-hydraulic modeling of the TRIGA core.

• Numerous high school, Penn State, and non-Penn State college/university groups participated in educational programs at the RSEC under the direction of Candace Davison during the year. In many cases, experiments teaching nuclear concepts were performed. The RSEC also supported educational events such as Boy Scout and Girl Scout merit badge programs. The facility hosted more than 1700 visitors during the fiscal year.

A complete list of groups hosted is presented in Appendix B.

• Increased reactor usage for University courses continued this year as multiple sessions were needed in the NucE 451 and NucE 450 laboratory courses.

An increased emphasis on graduate students taking NucE 444, Nuclear Reactor Operations, resulted in more reactor usage during the year.

. In light of concern for terrorist activities that could be directed against university research reactors, continuing efforts were made in expanding the total scope of facility security. Additional attention to security issues is expected to continue, both self-directed and in response to NRC guidance. The staff is meeting the challenge of providing security without compromising the education and research mission of the reactor facility.

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PERSONNEL PERSONNEL Several undergraduate students worked in work-study or wage payroll positions during the year. Daniel Skilone, Ashley Talley, Aaron Wilmot, and Doug Yocum assisted Candace Davison in facility educational programs for high school students. Jared Hoover, Fernando Palacios and Brian Pye assisted Dr. Kenan OnlIl on research projects.

Undergraduate Rachel Slaybaugh began training as a reactor operator during summer 2003 and received her reactor operator's license in June 2004. Undergraduates Adina LaFrance and Joshua LaFrance were hired to begin training as senior reactor operators in January 2004 and received their senior reactor operator's licenses in June 2004. Both Adina and Joshua had previous nuclear navy experience. Undergraduate Bert Tredway began training as a senior reactor operator in October 2003, but resigned from the program in January 2004.

L.

Figure 2. Candace Davision, Senior Reactor Opera-tor, Adanm Koziol, Senior Reactor Operator Intern, and Brenden Heidrich, Senior Reactor Operator.

Two staff promotions occurred during the year. Terry Flinchbaugh was promoted from manager, operations and training, to associate director for operations. Ron Eaken was promoted from a machinist A grade 2 position to a reactor machinist grade I position in technical service.

The following changes to the membership of the Penn State Reactor Safeguards Committee (PSRSC) were effective on Jan. 1, 2004. Committee chair Larry Hochreiter (professor, nuclear engineering, Penn State) completed his second term on the committee and was Figure 1. Reactor Operator Interns. Rachel not eligible for re-appointment. Randy Tropasso Slabaugh (front), Joshua LaFranceand Adina (manager of nuclear design, Exelon Nuclear) was LaFrance (back). reappointed to a second term.

Eric Boeldt (manager of radiation protection, Penn State)

Undergraduate Chanda Decker who was already licensed was reappointed to the committee. The committee as a reactor operator, received her senior reactor member with health physics expertise can serve an operator's license in June 2004.

indefinite number of consecutive terms. Committee member Tom Litzinger assumed the chairmanship of the Randy McCullough, instrumentation engineer, resigned committee upon Hochreiter's departure. Yousry Azmy his position on July 31, 2003. Randy was also licensed (professor, nuclear engineering, Penn State) was as a reactor operator. Eric Knepp was hired into the appointed to the committee.

engineering aide position on Sep. 2, 2003, and began training for a reactor operator's license.

4

TABLE I Faculty and Staff Title Jack S. Brenizer Professor & Program Chair, Nuclear Engineering

• • Mac E. Bryan Research Engineer/Supervisor, Reactor Operations Gary L. Catchen Professor, Nuclear Engineering

• • Thierry H. Daubenspeck Activation & Irradiation Specialist/Supervisor, Reactor Operations

• • Candace C. Davison Research & Education Specialist/Supervisor, Reactor Operations

• • Chanda C. Decker Reactor Operator Intern Wendy R. Donley Staff Assistant VII Ronald L. Eaken Reactor Machinist

• • Terry L. Flinchbaugh Associate Director for Operations

• • Brenden J. Heidrich Research Assistant Eric G. Knepp Engineering Aide

• • Adam W. Kozial Reactor Operator Intern

• • Adina K. LaFrance Reactor Operator Intern

• • Joshua A. LaFrance Reactor Operator Intern Jana Lebiedzik Research Support Technician III

• Randy A. McCullough Instrumentation Engineer (resigned)

• • Gary M. Morlang Senior Supervisor/Reactor Engineering Operations Jeremy M. Myers Computer Support Specialist Angela D. Pope Staff Assistant V

• • Alison R. Portanova Research & Service Support Specialist/Supervisor, Reactor Operations Paul R. Rankin Radiation Measurement Technician

• • Bret M. Rickert Reactor Operator Intern Susan K. Ripka Administrative Aide Ill

• • C. Frederick Sears Senior Scientist/Director, RSEC, Associate Professor, Nuclear Engineering

• Rachel N. Slaybaugh Reactor Operator Intern Sally Thomas Staff Support Kenan OnlM Senior Scientist/Associate Director for Research, Professor, Nuclear Engineering

• Licensed Operator

• • Licensed Senior Operator Wage Payroll/Work Study Jared Hoover Ashley Talley Fernando Palacios Bert Tredway Brian Pye Aaron Wilmot Daniel Skilone Doug Yocum 5

l1

TABLE 2 Penn State Reactor Safeguards Committee

• • Y. Azmy Professor of Nuclear Engineering, Penn State R. Benson Professor & Dept. Head, Mechanical & Nuclear Engineering, Penn State

• E. Boeldt Manager, Radiation Protection, Penn State Environmental Health & Safety F. Eisenhuth Sr. Engineer, Pennsylvania Power & Light Susquehanna Steam Electric Station

• L. Hochreiter, Chairman Professor, Mechanical & Nuclear Engineering, Penn State K. Ivanov Associate Professor in Charge of Fuel Management, Penn State

• • • • T. Litzinger, Chairman Professor & Director of Leonhard Center, Penn State 1.McMaster Retired Deputy Director, RSEC G. Robinson Professor Emeritus, Nuclear Engineering, Penn State C.F. Sears Ex-Officio, Director RSEC

• R. Tropasso Manager of Nuclear Design, Exelon

• Served through January 1, 2004

• • InitialAppointmentJantiamy 1, 2004

• • • Reappointedeffective Janualy1, 2004

• Assumed Chairmanshipon January 1, 2004 6

FIGUREI RSEC Organization Chart lDircctor* l l Assoc. Director for Research Assoc. Director for 0 Research Assistant*"*

lResarch & Education l l r. Su-Jisor/ Reactor l Specialist"$ l Enginer~ing Operations

• l RRe arcil & Sen-ice Support Wage Payroll _ Specialist *

< Work Studly I Licensed Operator Licensed Senior Operator

REA CTOR OPERA TIONS

- . CS- 7S V1!

REACTOR OPERATIONS Research reactor operation began at Penn State in 1955.

In December 1965, the original 200 kW reactor core and control system was replaced by a more advanced General Atomics TRIGA core and analog control system.

TRIGA stands for Training, Research, Isotope Production, built by General Atomic Company. The new core is capable of operation at a steady state power level of 1000 kW with pulsing capabilities to 2000 MW for short (milliseconds) periods of time.

In 1991, the reactor console system was upgraded to an AECL/Gamma-Metrics dual digital/analog control system. This system provided for improved teaching and research capabilities and features a local area network whereby console information can be sent to laboratories Figure 1. AMac Bryan operates at the reactor and emergency support areas. ,.cnl up,, us c-.

Utilization of the Penn State Breazeale Reactor (PSBR) falls into four major categories:

OPERATIONS Education Utilization is primarily in the form of laboratory classes The PSBR core, containing about 7.5 pounds of Uranium-235 in a non-weapons form, is operates at a depth of conducted for graduate and undergraduate degree approximately 18 feet in a pool of demineralized water.

candidates and numerous high school science groups.

The water provides the needed shielding and cooling for These classes will vary from the irradiation and analysis the operation of the reactor. It is relatively simple to of a sample, non-destructive examinations of materials using neutrons or x-rays, or transient behavior of the expose a sample by positioning it in the vicinity of the reactor at a point where it will receive the desired reactor to the calibration of a reactor control rod.

radiation dose. A variety of fixtures andjigs are available for such positioning. Various containers and irradiation Research tubes can be used to keep samples dry. A pneumatic Involves radionuclear applications, neutron depth transfer system offers additional possibilities. A heavy profiling, neutron radiography, gamma irradiation, water tank and neutron beam laboratory provide for several research programs by faculty and graduate neutron transmission, neutron radiography, and neutron students throughout the University, and various beam activities. Core rotational, east-west and north-applications by the industrial sector. south movements, provide flexibility in positioning the core against experimental apparatus.

Training Programs for PSBR Reactor Operations Staff. In normal steady state operation at 1000 kW, the thermal neutron flux available varies from approximately 1 x Service 1013 n/cm2 /second at the edge of the core to Involves radionuclear applications, neutron transmission approximately 3 x 1013 n/cm2/second in the central region measurements, radioscopy, semiconductor irradiations, of the core.

isotope production and otherapplications by the industrial sector. When using the pulse mode of operation, the peak flux for a maximum pulse is approximately 6 x 1016 nlcm 2/

second with a pulse width of 15 milliseconds at half maximum.

Support facilities include hot cells, a machine shop, electronic shop, darkroom, laboratory space, and fume hoods.

8

each year.

STATISTICAL ANALYSIS INSPECTIONS AND AUDITS Tables 3 and 4 list Reactor Operation Data and Reactor On November 2-3, 2003, an audit of the PSBR was Utilization Data-ShiftAverages, respectively, for the past conducted to fulfill a requirement of the Penn State three years. In Table 3, the Critical time is a summation Reactor Safeguards Committee charter as described in of the hours the reactor was operating at some power the PSBR Technical Specifications. The audit was level. The Subcritical time is the total hours that the conducted by Bob Agasie, Director, Nuclear Reactor reactor key and console instrumentation were on and Laboratory, University of Wisconsin-Madison. The under observation, less the Critical time. reactor staff implemented changes suggested by that report, all of which exceed NRC requirements.

Subcritical time reflects experiment set-up time and time spent approaching reactor criticality.

The Number of Pulses reflects demands of undergraduate labs, researchers, and reactor operator training programs.

Square Waves are used primarily for demonstration purposes for public groups touring the facility, as well as researchers and reactor operator training programs.

The Number of Scrams Planned as Part of Experiments reflects experimenter needs. Unplanned Scrams from Personnel Action are due to human error. Unplanned Scrams Resulting from Abnormal System Operation are related to failure of experimental, electronic, electrical Figure 2. TIhierry Daubenspeck. senior reactor or mechanical systems. operator,assists in performing a calibration proce-(lhe.

Table 4, Part A, Reactor Usage, describes total reactor utilization on a shift basis. The summation of Hours Critical and Hours Subcritical gives the total time the reactor console key is on. IHours Shutdown includes time for instruction at the reactor console, experimental setup, calibrations or very minor maintenance that occupies the reactor console but is done with the key off. Significant maintenance or repair time spent on any reactor component or system that prohibits reactor operation is included in Reactor Usage as Reactor Not Available.

Table 4, Part B gives a breakdown of the Type of Usage in Hours. The Department of Mechanical and Nuclear Engineering and/or the reactor facility receives compensation for Industrial Research and Service.

University research and service includes both funded and non-funded research, for Penn State and other universities. The Instruction and Training category includes all formal university classes involving the reactor, experiments for other University and high school groups, demonstrations for tour groups and in-house reactor operator training.

Table 4, Part C statistics, Users/Experimenters, reflects the number of users, samples and sample hours per shift.

Table 4, Part D shows the number of eight hour shifts for 9

TABLE 3 Reactor Operation Data July 2001 - June 2004 01-02 02-03 03-04 A. Hours of Reactor Operation

1. Critical 1028 745 1070

2. Subcritical 424 414 417

3. Fuel Movement 40 0 6 B. Number of Pulses 124 125 116 C. Number of Square Waves 52 59 62 D. Energy Releases (MWH) 648 458 736 E. Grams U-235 Consumed 33 24 38 F. Scrams

1. Planned as Part of Experiments 9 16 1

2. Unplanned - Resulting From:

a) Personnel Action 2 0 1 b) Abnormal System Operation 2 2 2 I0

TABLE 4 Reactor Operation Data July 2001 - June 2004 01-02 02-03 03-04 A. Reactor Usage

1. flours Critical 3.8 2.9 3.9

2. Flours Subcritical 1.6 1.6 1.5

3. Hours Shutdown 2 2.1 2.4

4. Reactor Not Available 0.2 0.2 0.1 TOTAL HOURS PER SHIFT 7.5 6.8 7.9 B. Type of Usage - Hours

1. Industrial Research and Service 3.5 3.0 3.5

2. University Research and Service 1.3 0.8 1.4

3. Instruction and Training 1.3 1.6 1.9

4. Calibration and Maintenance 1.3 1.4 1.1

5. Fuel flandling 0.1 0 0 C. Users/Experiments

1. Number of Users 3.1 2.9 3.2

2. Pneumatic Transfer Samples 1.6 0.2 0.1

3. Total Number of Samples 4.6 3.2 3.5

4. Sample Hours 3.4 2.5 3.5 D. Number of 8 flour Shifts 271 255 273 IIl

GAMMA IRRADIATIONFA CILITY GAMMA IRRADIATION FACILITY The Gamma Irradiation Facility includes in-pool GAMMACELL 220 EXCEL DRY irradiators and a dry-shielded GammaCell 220 Excel IRRADIATOR irradiator. This provides a great deal of flexibility for dose rates and irradiation configurations. The GammaCell 220 Excel dry irradiator was acquired in July 2003 through funding from the U.S. Department IN-POOL IRRADIATORS of Energy INIE grant. The new irradiator is located in the back area of the Hot Cell Laboratory. This irradiator For the in-pool irradiators, the source rods are stored replaced the old GammaCell 220 Irradiator which was and used in a pool that is 16 feet by 10 feet, filled with housed in the same room as the pool irradiator. The new 16 feet of demineralized water. The water provides a irradiator has a dose rate that is considerably higher (by shield that is readily worked through and allows great a factor of 10) than the old Gammacell 220 irradiator.

flexibility in using the sources. Due to the number of Other advantages of the GammaCell 220 Excel include a sources and the size of the pool, it is possible to set up large irradiation chamber (approximately 6 inches in several irradiators at a time to vary the size of the sample diameter and 7.5 inches high), an automatic timer to move that can be irradiated, or to vary the dose rate. the sample chamber away from the source and the ability Experiments in a dry environment are possible by use of to conduct in-situ testing of components during either a vertical tube or by a diving bell type apparatus. irradiation. The only disadvantage is the decay heat from Four different irradiation configurations have been used the higher dose rate, which increased the temperature of depending on the size of the sample and the dose rate the irradiation chamber. The maximum dose rate is required. The advantage of the in-pool irradiators is that summarized in Table 5.

the dose rate can be varied in a manner which is optimal for agricultural and life science research.

In March 1965, the University purchased 23,600 curies of Cobalt-60 in the form of stainless steel clad source rods to provide a pure source of gamma rays. In November 1971, the University obtained from the Natick Laboratories 63,537 curies of Cobalt-60 in the form of aluminum clad source rods. These source rods have decayed through several half-lives, and the dose rates available are summarized in Table 5. The dose rates listed for the pool irradiator tubes reflect a new source configuration as of June 30, 2003, which increased the number of sources around the 6-inch tube.

_1- I_

Figure 1. In-Pool IrradiationFacility Figures 2 & 3. GaniniaCell 220 Excel Di) Irradiator being moved into the Hot Cell Laboratory 12

USE OF GAMMIA IRRADIATION SERVICES The use of the Gamma Irradiation facility has been increasing steadily. The number of the sample hours performed in the GammaCell 220 Excel was lower compared to last year due to the higher dose rate. More than 14,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> of"equivalent irradiation time" would have been needed if the old GammaCell 220 would have been used - this exceeds the number of hours in a year!

The utilization of the Gammacell 220 Excel was only at 16 percent capacity and we achieved more irradiations and irradiated for shorter times. Several departments on campus utilized the services of the Gamma Irradiation facility for a variety of purposes. Figure 2 shows some of the variety of samples and purposes for irradiations this past year. Other University and pre-college educational institutions utilized the gamma irradiation facility through research projects, INIE minigrant projects or the Reactor Sharing program. This information is outlined in the Research and Service utilization section and in Appendix A. Table 6 compares the past three years' utilization of the Cobalt-60 Irradiation Facility in terms of irradiation time and number of irradiations.

Figure 4. Rachel Slaybaugh, Reactor Operator Intern, inserts a sample into the GammanCell 220 Dry Irradiator 13

'II

TABLE 5 Summary of Current Ganima Irradiation. Facilities *as of.7/1/2004l Facility Maximum Dose Rate Sample Limitations in KRads/hour*

North Tube 33 Must be less than 6 inches in diameter 6-inch South Tube 25 Must be less than 3 inches in diameter 3-inch 10-inch Chamber depends on Cylinder approx. 10 inches in diameter by 12 inches in height source array GammaCell 220 Excel 1723 Cylinder approx. 6 inches in Diameter by 7.5 inches in height Dry Cell Irradiator _

TABLE 6

-Cobalt-60 Utilization DAta July 12001:-June 30 2004; l -- - --

01-02 01-02 02-03 02-03 03-04 03-04 Pool GamnmCell Pool GammaCell Pool GamnaCell Irradiator 220 Irradiator 220 Irradiator 220 A. Time Involved (Hours) _ _ _

1. Set-Up/Admin. Time 17 89 16 71 19 85

2. Total Sample Hours 394 5667 1835 7352 1086.5 14232 B. Numbers Involved ___

1.Total Irradiations 33 227 84 223 50 249

2. Samples Containers Runt 204 1200 958 959 294 1379

3. Different Experimenters 5 29 11 25 _ 11 39

4. Configurations Used 4 N/A 4 N/A 4 N/A Note that each sample container may contain multiple samples and that multiple samples may be run together inone batch.

2 Note the sample hours for the GammaCell 220 Excel would be equivalent to over 14,000 sample hours in the old GammaCell 220.

FIGURE2 Irradiation Usage 16000 il_______________________

14000 . - ..

. I1 i1 . '. ' .1- - ' ' " ' 1 '

12000 . . i - _

6 10000 - --

.4,, ., , . - -.. 1-

.° 8000 600

_~ 6000 ~8i: __-___

4000 ..  ; a-2000  ; . -.-

0=

1999 - 2000 2000 - 2001 2001- 2002 2002- 2003 2003 -2004 Fiscal Year I-- Pool usage (hrs) -a- Gamma Cell Usage (hrs) GammaCell220 . _Equivalents

- _l.n.s; .

15

'I

FIGURE3 Gaumna Irradiation Uses anud Exmunples Genetic Clhnnges Strilizatdon Class-Poiects-awl Denvmmtrnthn Medical & Lab ontorv Products TaebnSewd Water I

Poinxrties Fruit Flies ffi Beef T11bleS Alt Ptt#'-q 0%

Mwuboms Crnss-Tinlncv ofPolvmn Soil & Le rvts for Erntonmenbl Food Irradiation I Reseamh SIMtbenis Bread 0-0--, 0-0-0-0 0 0II Ar, 0-0-0-0

EDDUCATIONAND TRAINING El I

0

-- - I S .90

- 'a -

- I --

i I

i

EDUCATION & TRAINING The RSEC staff utilized the facilities and equipment to High school student Katherine Ann Colburn collected provide educational opportunities and tours for student water samples at different locations and used NAA for and teacher workshops, many of which were conducted analysis of the samples. Candace Davison of the Penn as part of other programs on campus. These programs State Reactor Facility worked with a group of pre-are typically conducted through the Penn State College college science teachers to develop an equipment loan of Engineering, the Women in Science and Engineering program for teaching nuclear science. Guy Anderson, a (WISE) Institute, the Continuing and Distance Education local teacher utilized the equipment to improve the ratio Program, Campus Admissions and the University of students to equipment thus providing a better learning Relations Offices. The student programs included: the experience for his students.

VIEW program, Women in Science and Engineering (WISE) week, Pennsylvania JuniorAcademy of Sciences and other programs associated with campus activities. NUCLEAR SCIENCE & TECHNOLOGY COURSE Facility staff and ANS student members have participated A one-week course on Nuclear Science and Technology in activities for the Boy Scouts of American and the Girl was conducted from July 15-19, 2003. John Vincenti Scouts of the United States of America. Facility staff was the coordinator of the course, which was held, again and students provided input into the development of a based upon the success of the previous course. Fourteen revised nuclear science merit badge to replace the teachers attended the workshop and received free Geiger atomic energy merit badge booklet. Students and staff Counters through a grant from the American Nuclear also provided suggestions for the requirements of a Society and U.S. Department of Energy. Candace nuclear science interest patch for Girl Scouts. The Davison provided instruction on radiation, reactor student ANS members conduct programs for scouts at basics, nuclear applications and conducted experiments the facility. Twenty-six Girl Scouts participated in at the facility for the participants.

activities to earn the nuclear science interest patch sponsored by the Penn State Student ANS chapter. A short report on the Girl Scout program is included. TOURS In addition to the full or half-day programs with Job shadowing was another means by which some pre- experiments, educational tours were conducted for college students learned about nuclear applications. The students, teachers, and the general public. All groups, students spent from half a day to several days shadowing including those detailed in the above sections, which staff and faculty at the facility to enhance their toured the facility are listed in Appendix B. The RSEC understanding of nuclear technology and careers. operating staff along with the mechanical and nuclear engineering department conducted several open house events for the Parent and Family Weekend, the general public and potential undergraduate orgraduate students.

U.S. DEPARTMENT OF ENERGY - INIE Over 300 people participated in Open House and "Spend MINIGRANT a Day" experiences.

Several educational institutions participated in mini-grant projects at the RSEC facility through the INIE minigrant process. The following is a synopsis of the institutions that participated in educational outreach and educational research projects utilizing the Penn State Reactor Facility. All of the participants traveled to the reactor facility to learn about nuclear applications and understand some of the procedures and equipment utilized in the projects. The Central Virginia Governor's School conducted a neutron radiography experiment and utilized the gamma irradiation capabilities. Neutron irradiation and neutron activation analysis were discussed, but this presented a problem in conducting projects due to the production of radioactive materials.

Two secondary science teachers, Guy Anderson from Bald EagleArea High School and DwightJohnston from Figure 1. A school tour group looks over displays in Spring Grove Area High School conducted projects to the Reactor Bay assist in improving their nuclear science curriculum.

17

ACADEMIC INSTRUCTION The RSEC supports academic instruction by providing information and expertise on nuclear technology topics, tours and experiments conducted at the facility and through the availability of specialized equipment and classroom/laboratory space.

The joint instructional experience for students in the IE 408W (Human Factors) course was continued in the fall semester. The students were instructed on reactor basics so that they could understand the control signals and input along with an overview of the control console in the classroom. The students then went into the control room where they observed a start-up and the operator's Figure 3. Fredl Sears, director RSEC, teaches the actions. They also observed the reactor while at power. Reactor Operations course, NicE 444.

Feedback from the students was very positive concerning their real-world experience.

The reactor classroom was utilized as the base of instruction for several courses including; Freshman Seminar (Fall 2003 and Spring 2004), NucE 444, NucE 450, and NucE 451. The TRIGA reactor and Cobalt-60 irradiation facilities were used by several nuclear engineering courses and courses in other departments of the universitv as outlined in the table below.

Figure 4. NucE 451 sttudlents participatein a laboratory session Utilizing the Breazeale Reactor racility.

Figure 2. Brendlen Heidrich, research assistant, demonstrates ejection of the Transient Rod mhuring a Reactor pulse to Freshmna Se'nina,

.i

TABLE 7 Semesteri. l Course;-- Instructor l Students Hours Summer 2003 SCIED 498B - Nuclear Science and J. R. Vincenti 10 6 Technology Workshop C. C. Davison Fall 2003 NUCE 00IS - Freshman Seminar _ J. S. Brenizer 37 14 Fall 2003 Nuc E 301 - Fundamentals of Reactor R.M. Edwards 28 2 Physics Fall 2003 Nuc E 310W - Issues in Nuclear A. Motta 2 1 Engineering Fall 2003 Nuc E 401 - Introduction to Nuclear L. Hochreiter 6 5 Engineering Fall 2003 Nuc E 451 - Experimental Reactor R.M. Edwards 21 20 Physics Fall 2003 Nuc E 444 - Nuclear Reactor C. F. Sears 4 45 Operations _

Fall 2003 ENGR IOOS - Freshman Seminar A. Motta 13 Fall 2003 Food Science 413 - Science & R. B. Beelman 13 3 Technology of Plant Food Fall 2003 IE 408 W-Human Factors L. Newman 63 6 Fall 2003 ME 33 G. Talmage 28 7 Spring 2004 NUCE OOIS - Freshman Seminar J. S. Brenizer 9 14 Spring 2004 Nuc E 444 - Nuclear Reactor C. F. Sears 5 90 Operations Spring 2004 Nuc E 450 - Radiation Detection and R.M. Edwards 13 6 Measurement Spring 2004 ME 30H D. A. Santavicca 4 1 Spring 2004 CHEM 036 (Penn State Altoona) _ C.S. Reed 8 2 19

m 1 FIGURE4 Educational Institutions Visiting the RSEC 0

II Oavln,,l JmidtI SIhn " afod meSim It1 El*0l1wir 111!11 behin Lalos-mm"

NE UTRON BEAM LABORATORY I; -I Wr5,

. .-I. L Ad

NEUTRON BEAM LABORATORY The Neutron Beam Laboratory (NBL) is one of the NEW BEAM PORTS AND BEAM HALL experimental facilities at the RSEC. Well-collimated beams of neutrons, thermalized by a D2 0 tank, are passed EXPANSION into the NBL for use in various neutron beam techniques.

When the reactor core is placed next to a D2 0 tank and Due to inherited design issues with the current graphite reflector assembly near the beam port locations, arrangement of beam ports and reactor core-moderator thermal neutron beams become available for neutron assembly, the development of innovative experimental transmission and neutron radiography measurement from facilities utilizing neutron beams is extremely limited.

two of the seven existing beam ports. In steady state Therefore, a new core-moderator location in PSBR pool operation at I MW, the thermal neutron flux is Ix lI' nf and beam port geometry needs to be determined in order cmisec at the edge of the core and 3x10'3 n/cm 2sec at to build useful neutron beam facilities. A study is the central thimble. The Penn State Breazeale Reactor continuing with the support of DOE-INIE funds to (PSBR) can also pulse with the peak flux for maximum examine the existing beam ports for neutron output and pulse - 6x10'6 n/cm2 sec with a pulse width of 15 msec to investigate new core and moderator designs that would at half maximum. be accessible by additional beam ports. We envision a location in the pool where reactor core would be CURRENT STATUS OF PSBR BEAM "parked" and surrounded by a moderator (D2 0 or PORTS graphite). New beam ports would be geometrically aligned with the core-moderator assembly for optimum neutron output.

The PSBR has seven beam ports. The internal diameter of the beam ports are four inches for BP #3 and BP #5; The new core-moderator and beam port arrangement five inches for BP #1 and BP #7; and six inches for BP requires expansion of the existing beam laboratory in

1. 2, BP #4 and BP #6. The center of BP #4 is 65 inches order to place instrumentation, neutron guides, and beam from the pool floor while BP #1, BP #3, BP #5 and BP catcher, etc. The new beam hall will have a total of 3,700

1. 7 are 60 inches and BP #2 and BP #6 are 54 inches sq ft of experimental area (the existing area of -1,000 from the pool floor. With the current setup of reactor- sq ft plus a new additional area of -2,700 sq ft). Also, core-moderator assembly only BP #4 is at the centerline about 3,100 sq ft of new office and meetingfclassroom of the TRIGA core. (Active length of TRIGA fuel is space will be added in the second floor of the expanded 15"). BP #1, 3, 5 and 7 are five inches below the beam hall to support students and faculty working in this centerline of the core and BP #2 and 6 are eleven inches area.

below the centerline of the core. The core grid assembly does not permit lowering the core more than the current arrangement. When the PSBR reactor was built, MTR type fuel elements with active length of 24" were used.

With the MTR fuel the beam port arrangement did not limit the maximum neutron output. In the mid 60's the PSBR was converted from MTR type to TRIGA type fuel.

With TRIGA fuel, only one beam port is at the centerline of the core active area, four beam ports are five inches below the centerline and two are eleven inches below the centerline (below the active fuel region). Because of these inherited limitations only two beam ports are currently being used. BP #4 with 3 x I07 n/cm2sec flux at the aperture is used for research, primarily neutron radiography and radioscopy, and BP #7 with 10 an/

cm 2sec neutron flux is used for service activities Figure 1. A picture of BP #4 collimator aperture and involving neutron transmission measurements. Since the BP #4 collimators are primarily designed and testing rig of a semiconductor memory ch'ip.

optimized for neutron radiography and radioscopy measurements, it is not possible to obtain desired results for other measurements. We are currently trying to use BP #4 for all of our research projects. Due to space limitations, we must shuffle delicate research equipment around. More importantly, each project or experimental techniques require a special or dedicated neutron beam with different collimations and neutron flux.

21

__ - IL_

Architectural plans for the RSEC expansion for a newv Projects utilizing the NBL during the year included the Neutron Beam IHall and Neutron Beanm Ports facilities following:

are completed. Working with a professional architectural firm, a contractor, and related personnel from various

• Time-of-Flight Neutron Depth Profiling at the university functions, we obtained a firm estimate for the Penn State University Breazeale Nuclear Reactor expansion cost. Internal benefactors of the new neutron (see Research and Service Utilization Section, beam facilities are identified. We obtained support page 73).

letters or expression of interests from about 30 faculty members from four different colleges within the

• Neutron Beam Characterization of the Breazeale university. More than half of the total budget for Nuclear Reactor at Penn State, Radiation Science expansion is currently available, and efforts to raise the and Engineering Center (see Research and remaining portion of budget continue. Service Utilization Section, page 62).

Research areas envisioned for RSEC's new beam port/

• Testing Neutron-Induced Soft Errors in beam hall design are as followvs. Neutron Depth Semiconductor Memories (see Research and Profiling facility for depth vs. concentration Service Utilization Section, page 65).

measurements, impurity determination of He-3 and B-10 in semiconductors, metal and alloys; Cold Neutron

• Soft ErrorAnalysisToolset (SEAT) Development Source and Cold Neutron Prompt Gamma Activation (see Research and Service Utilization Section, Analysis for neutron focusing research, nmaterials page 51).

characterization and determination of impurities in historically or technologically important material;

• Study of Water Distribution and Transport in a Neutron Powder Diffraction for structural Polymer Electrolyte Fuel Cell Using Neutron determination of materials, and a Triple Axis Imaging (see Research and Service Utilization Diffractometer to train students on neutron diffraction Section, page 44).

and perform preliminary structural determinations of materials.

• Neutron Imaging System Improvements (see Research and Service Utilization Section, page 57).

• Modelling of existing beam-port facility at Penn State Breazeale Nuclear Reactor by using MCNP (see Research and Service Utilization Section, page 81).

• Investigation ofpreferential flow of water in sand samples using real time neutron radiography.

Collaborative work wvith Cornell University, Ward Center for Nuclear Sciences.

• Neutron transmission measurements and neutron radioscopy were conducted for borated metals and other borated materials for numerous companies.

• Radiographic and radioscopic techniques were demonstrated as part of several student projects; Figur, a. A picture of a semticondluctor nie~nior chipy including demonstration of neutron and x-ray through an aperture ait a p~olvethleire/lemd shielding imaging for the Governor's School students and fixtur-e. students enrolled in the freshman seminar (NucE 00 IS). The students assembled plaques containing a variety of objects and predicted their neutron & x-ray attenuation characteristics.

Experiments wvith neutron & x-ray radiography confirmed their predictions.

22

.3I

RADIONUCLEAR APPLICA TIONS LAB ORA TOR Y

• _ v m 1

....-..._ I 4t -

• I . . . .-. -

- . I :..:;

A. Service B. Research

RADIONUCLEARAPPLICATIONS LABORATORY Section A. Service The Radionuclear Applications Laboratory (RAL) provides consulting and technical assistance to personnel wishing to use radionuclear techniques in their research projects. The majority of these projects involve neutron activation; however, the staff is also able to provide services in radioactive tracer techniques, radiation gauging, and isotope production for laboratory, radionuclear medicine or industrial use. RAL personnel support daily RSEC operations by performing analyses of water, air monitor filters, and other samples as needed to meet regulatory requirements.

During the past fiscal year, a total of 444 semiconductor irradiations were performed for nine different companies. The devices were prepared for irradiation in accordance with accepted procedures. Afterwards, Figure 1. Thierry Daubensped *, activation and the l-MeV Silicon Equivalent fluence was calculated utilization specialist/seniorre(actor operator from the flux monitors irradiated with the devices. The explains Pneumatic Transfer s)'stem to studentsfionm irradiated devices were analyzed to determine the the University of Pittsburgh.

radioisotopes present for shipping and licensing requirements. RAL personnel returned irradiated devices in accordance with NRC and DOT regulations.

RAL personnel performed a total of 18 isotope __________

production runs of Sodium-24, Bromine-82 and Argon-41 for industrial use during the past fiscal year. If necessary, personnel are able to analyze and test chemicals not currently on our approved list.

Penn State students and faculty members continue to use the services offered by the RAL. Irradiations and analytical work were performed for graduate and undergraduate students in the nuclear engineering and the anthropology programs. Nuclear engineering students use the RAL for various projects being -

performed at the RSEC.

The RAL assisted students from the anthropology department in characterizing various samples of obsidian and rhyolite using Neutron Activation Analysis (NAA).

This analysis involves determining the concentrations of specific elements in various obsidian and rhyolite samples to identify the source of the samples. The _

obsidian samples originate from Central America and the rhyolite samples are collected in the United States.

This is an on-going project that began years ago. igure 2. Ortec Automatic SamvPle Changer used for long-lived isotopes.

23

RADIONUCLEARAPPLICATIONS LABORATORY Section B. Research In the past year, the Instrumental Neutron Activation former Soviet Union. These samples span most of the Analysis (INAA) facility was completed at the Breazeale period from 7000 BC to the present. All Nuclear Reactor. This includes installing two Dry dendrochronologically dated samples at the Wiener Irradiation Tubes (DT) in the reactor core, getting the Laboratory are available for this study.

Automatic Sample Handling System (ASHS) up and running, setting up the analysis system with a High-Purity Staff and students ofthe Wiener Laboratory have already Germanium (HpGe) Detector, a Digital Spectrum prepared approximately three thousand samples of wood Analyzer and Genie-2000 software, and doing the flux for this study. A dedicated NAA system was built at measurements necessary to identify flux peak area for Cornell's Ward Center for Nuclear Sciences. The sample irradiation positions. A close-up picture of prepared samples, gamma spectroscopy system, and ASHS showing the sample tray and robot arm is given sample changer were transferred to Penn State's below. A compton suppression system is being Radiation Science and Engineering Center.

purchased with INIE funds in order to make more in- Measurements will continue using the I MW Breazeale depth analysis of some samples using NAA. Also, Room Nuclear Reactor. Please see details of this project in 4 is being converted to a NAA sample preparation facility. page 69 of this report.

Figure 4. Tree samples.

Figure 3. Gradtuate student Danielle Haauck gathers her samples fionz tile sample changer The current main activity at RAL is a dendrochronology project. The objective of this study is to determine experimentally periods of global environmental stress during the past six thousand years using tree samples p.

already collected and dated and neutron activation analysis (NAA). The result of this study will provide Figure 5. A tree samplefionm Istanbul. Belgrade climate modelers withl a much needed extended timeline.

Forest. The innermost pin is placed at 1800 A.D.,

This study is the first coordinated dendrochemical study other pins follow at 50-year intervals.

of a period longer than one hundred years, and the first study in the archaeologically important eastern Mediterranean. The Malcolm and Carolyn Wiener Laboratory for Aegean and Near Eastern Dendrochronology at Cornell University, archives 40,000 individually-dated tree samples with 4.5 million rings from 109 forests in the eastern Mediterranean and 24

PATHFINDER FUEL SHIPMENT PATHFINDER FUEL SHIPMENT INTRODUCTION During the latter portion of 2003, 417 Pathfinder Fuel assemblies were removed from storage at Penn State and transported to Sandia National Laboratories for utilization and storage. The first transfer of the fuel assemblies occurred on Sep. 9, 2003 and the tenth transfer occurred on Nov. 18, 2003.

BACKGROUND In October 1969, the Atomic Energy Commission loaned 417 fuel assemblies to Penn State to be used in a subcritical assembly. The subcritical assembly was Figure 2. Interior view of ttefitel racks in PSU stor-never built and Penn State requested the uranium be age room.

returned to DOE control. The fuel assemblies were_

stored in a vault. Each fuel assembly was marked with a unique number used to support inventory control and was encased in a 1 inch O.D. sleeve which also had a unique marking. The inventory records showed the storage rack location of each fuel assembly by the unique __I__

markings. The assembly ends were free of rust and dirt and in excellent condition. Likewise there was no rust or indications of damage on any of the sleeves that were visually inspected.

PREPARATIONS FOR RETRIEVAL The project team for the retrieval of the fuel assemblies was made up of representatives from the Department of Energy (DOE), GEM Technologies Inc. (GEM), Penn State and Sandia National Laboratory (SNL).

Figure 3. A member of GEM personnel helps to load fitel into the cask.

RETRIEVALEFFORT The fuel assemblies were transported from Penn State to SNL in a Framatome commercial nuclear fuel transport cask with an internal liner. The cask was specially modified for use with the Pathfinder fuel, and transported on a semi-tractor trailer. Figure I shows the cask and semi-tractor trailer. Penn State provided the instructions for the packing of the fuel assemblies in the WE-I container and the associated radiological surveys. The Penn State Pathfinder Retrieval Plan provided detailed cask handling instructions and incorporated Framatome procedure: MA-649, Pathfinder Fuel Packaging, Shipping, and Container Storage for the WE-I Shipping Container. Figure 3 is a Figure 1. Franmatome cask on semi-tractor trailer, view of GEM personnel helping to load fuel into the cask.

25

- -- -LML Figure 4. View of tihe cask partially loade(l.

Figure 6. Removal of one of ti/e owl O-rings.

Forty-three fuel pins were loaded into the cask for each trip to the Sandia National Laboratory, with the exception of the tenth and last shipment, where only 30 elements were left.

Figure 7. Dave Beriocchii of Pemn State Raliation Pro-tection performing a neutilon survev of the loaded cask.

Figure 5. Ron Eaken, Penn State Atlaclhinist c/rills holes in the old O-rings in the cask end plate in preparalion for removing them.

< ra - R.e.iri Stt : a- -

n State Uraniumn Retrieval Leams 26 a,

LOWPRESSURE INTEGRAL TEST FA CILITY I

I I I

I F

-. £-

LOW PRESSURE INTEGRAL TEST FACILITY INTRODUCTION The Penn State Low-Pressure Integral Test Facility (LPITF) is a one-half height scaled representation of General Electric's Simplified Boiling Water Reactor (SBXVR). The unique characteristic of the facility is that it was designed, built, and engineered by Penn State Nuclear Engineering undergraduate students. The facility was started in 1995 with funding from the Dean of Engineering. Subsequent funding was obtained from different companies, such as Westinghouse, Rosemount-Fisher and others as well as matching funds from the Department of Energy. Penn State students participated in the scaling analysis used for the design, the hardware design, and fabrication of the facility components, analysis of the facility response, testing and analysis associated with the data. The facility operates near atmospheric pressures to take advantage of displaying boiling phenomenon at relatively lower temperatures.

The facility underwent a great deal of modification in 2003. The previous facility design had some problems with the two-phase natural (re)circulation. A new design was introduced to overcome some of the problems in flow stability (Figure 1). The new design also incorporates a motor actuated valve to improve the controllability of the loop (Figure 3).

Figure I - Detail of the modifications to the downcomer line and crossover leg.

27

DESCRIPTION OF FACILITY The reactor core is simulated using 12, one-half height electric heater rods, as can be seen in Figure 2. Four rods have four embedded surface thermocouples each, which determine the temperature profile along the bundle. Additional heater rods have a thermocouple near the exit of the heated length. The heater rods are connected to silicon controlled rectifiers (SCR), which provide the electrical power to the rod bundle. The glass channel diameter is 3-inches, wwhich was obtained by scaling the facility to the SBWR.

The core and the downcomer regions of the test loop are partially made of borosilicate glass so that the flow can be seen.

This configuration allows students to visually study the boiling process and two-phase flow behavior over a range of thermal-hydraulic conditions. Figure 3 shows the front-view of the test loop. To the right is the borosilicate glass core.

There are several penetrations on the core section for instrumentation including pressure transducers, void probes, and thermocouples.

I.

I 2 - I I:.

p..

{

• 1' I

'I I - -," - - * **! *i Figure 2 - Core rod layout.

28 I

Figure 3 - Front view of the test loop core section. TMe core is located on the basement of the Cobalt-60 irradiationfacilitjy MODIFICATIONS AT THE FACILITY The previous design had stability problems for two-phase (re)circulation experiments. The facility was designed to simulate the basic behavior of SBWR, however drastic differences in operating conditions resulted in major problems in the operation of the facility. First of all, SBWR operates at pretty high pressures relative to the LPITF. Operation at near atmospheric pressures makes the facility vulnerable to gravity, acceleration, and friction pressure drop; because as the water rises in the chimney section, it loses its head resulting in a considerable pressure loss compared to the operating pressure level. This has a significant impact on calculations regarding to two-phase flow. This cannot be resolved by any means other than changing the operating pressure of the facility.

The other problem was flow reversal to the main condenser: Since the two-phase flow experiments did not involve the main condenser in order to reduce water inventory, the portions of the facility above the steam separator were under vacuum. Water at a relatively higher pressure forced water/steam mixture through the condenser return line. Water forced to the condenser got cooled down and turned back to the circulation below saturation temperature resulting in change in temperature distribution along the loop.

29

i-The new design employs a three-leg downcomer section, which separates steam separator return line, condenser return line and downcomer line from each other. This way water/steam mixture has a less probability to flow to the condenser and affect the temperature distribution of the system at quasi-equilibrium. This modification is expected to reduce geysering and improve two-phase flow stability.

Figure 4. Miolifled d(lowtncoiter section: This lesign eliminates flow reversal to the steam separator an(dor main con lens.er.

One other modification involved the flow control: Flow rate is related to the temperature distribution along the loop and the temperature gradient between the hot and cold legs. There was no direct control over the flow, but through the condenser flow rate, which had a minuscule effect. With the addition of a flow control valve (Figure 5), one can restrict the maximum flow rate through the core and reduce the number of geysering cycles in the unstable two-phase flow regime. The electric motor actuated valve is equipped with a bypass line to guarantee a minimal flow rate in the case of a valve failure.

30

Figure S. Electric motor actuated valve and bypass valre.

INSTRUMENTATION The state of the loop is observed through a number of instrumentation:

i. Flownmeter: A very sensitive magnetic flowmeter; located on the pipe between the downcomer and heater rod bundle lower plenum.

ii. Pressure transducers: Absolute and differential pressure measurements to estimate the average void fractions in two-phase flow.

iii. Void probes: The miniature void probes penetrate into the piping and bundle, and determine the local void concentration at different locations.

is, Thermocouples: There are two different J-type thermocouples: surface thermocouples, which are inside the heater rods and measure the heater rod surface temperature; and fluid thermocouples, which measure the local fluid temperature.

The computer hardware allows up to 64 simultaneous thermocouple connections.

i: Power transducers: The power applied through the SCR's is read back to verify electrical heat input.

31

AE A computer reads the measurements and displays them through an interface application designed in LabVIEW (Figure 6). This application also interfaces to the control the power signal for SCR's, which in turn controls the electricity input to the rod bundle.

D - .... .71 e sirTmiae sM kAh Intel 1 ftQ. Io

• 4-_

. m*

Su II 2.,

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= -o - -

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, "d "O*r n I.V Z"U , ,,, a, ,t!S

,,~ , np~w_

s P.b-. . *' I thw O~tvti_*lrli .sl Figume 6 - Screensiotfronm t/c Lab VIEW main control interface.

TYPES OF EXPERIMENTS The main objective of the test loop is for students to understand the principles of single-phase and two-phase natural circulation flow and heat transfer behavior. The students determine energy balances over the system, and observe the two-phase natural circulation.

3J of

Single-Phase Natural Circulation Experiments During 2000-2001, single-phase experiments were performed in the spring. The students were requested to check the physical integrity of the facility, get acquainted with the instrumentation, and verify that the electrical energy transferred to the core matched the energy transfer in the primary side of the main condenser as well as the energy transfer in the secondary side of the main condenser. The students also developed calculational models to predict the natural circulation flow in the test loop. Calculations were also performed with the TRAC-PF-I code.

10-up I

I j

iisd IBude D i l lI V .i

- ------J- __

TT_

rTr77" ,.I a low 2 301Ti NM (Oo sowo 00 mA Wumo larta Tiff*(aecl Figure 7 - History of the core mean temperatures during a single-phaseflow.

Figure 7 and Figure 8 show the fluid temperature behavior during the single phase natural circulation experiment along the core and in the main condenser. The flow becomes established as the temperature difference develops between the hot and the cold legs, as can be seen in Figure 9. The coolant channel axial temperature distribution is shown in Figure 10 for this experiment.

C(Z-I

_ _w~~

i Nrw~ywwe I I PflnarY 4" A_

I - . bW9 -- "

-n I 0 1v 2000 30 40 50 0 7000 8000 9000 i100 Tirrm (sec 7_1

.0 E I

=S i 100 2 300 4000 1S TOMre Jsec Figure 8 - Temperature history in the main condenser.

34 Co3 .,

.....St......

....... ...... . "I'll I'l . .. . ........

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-A. T. _._

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- I 3' 1 l I I 44 01 i a) . . 4, ,0, I 1 a 100 00 ZW 4Ww 54 600 7M M woo 1o Tinve 4$ipcl Figure 9 - Single-phase naturalcirculationflow rate.

1g~ CDe

'I 1'J i o vo a

I.u 1iff ptmih <1"O Tfn. 4e I Figure 10 D profile along the core of the fluid temperaturefor this particularexperiment.

35

Two-Phase Natural Circulation Experiments Two-phase natural circulation experiments have also been performed in the facility and are very useful for the students to observe the boiling process and flow regime behavior along the vertical channel, which contains the rod bundle.

Subcooled nucleate boiling can be observed, with very small bubbles being formed at the heater rod surfaces. As the coolant is heated to saturation, bulk boiling occurs and several different flow regimes such as bubbly, slug, and churn-turbulent flow can be observed.

110 Bundle Inlet

] Bundle Exit 100

= _I-- - _

90 80 6_ 70 -- - 1-1 __ I'll, i I -

'0 60 r- - I - - - - ,t - _. -

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40 - -- ~

30 - - - - i I

- __ i I- - - - - - -

10 - I _I 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 Time (hr)

Figure II - Core fluid temperature history.

The two-phase natural circulation experiments are initiated as a single-phase natural circulation test to heat the fluid to the saturation temperature. Once the fluid approaches saturation temperature, the facility is partially drained, which reduces the system pressure. As a result of the reduced system pressure, the remaining water in the facility starts to boil with lower heat input. Figure 11 shows the temperature of the bundle inlet and exit as the facility transitions into a two-phase mode after approximately three hours.

36 GCQ5$

OF 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 Time (hr)

Figure 12 - Flow rate during the two-phase natural circulation experiment.

Figure 12 shows the stable single-phase natural circulation flow, which then transitions to a very oscillatory flow once the system is in two-phase natural circulation. The two-phase flow oscillation experiments are part of a Department of Energy NEER program, which studies BWR flow/power stability.

PI I.',

i 1 , 'I Figure 13 - The riser, chimne) sections of the core; crossover leg, and steam separator.

37

i_:a_

CONCLUSIONS The Penn State Low Pressure Integral Test Facility has proved to be a very effective learning tool for nuclear and mechanical engineering students. This facility allows the students to gain "hands-on" learning experiences in design, fabrication, and thermal-hydraulic testing and analysis. Itprovides the students with an opportunity to observe the complex boiling and tvo-phase floxv processes that occur in commercial light water reactors and other boiling systems.

Figure 14 - A closer look to the crossover leg and the steam separator.

38

.,1

ANGULAR CORRELATIONS LABORATORY I

kill

ANGULAR CORRELATIONS LABORATORY The Angular Correlations Laboratory has been in Currently Professor Catchen is executing a research operation for approximately 14 years. The laboratory, program funded by the Petroleum Research Fund of the which is located in Room 116 and Room 4 of the RSEC, American Chemical Society. It is titled: "Drag is under the direction of Professor Gary L. Catchen. The Reduction in Turbulent Flows: Direct Observation of laboratory contains three spectrometers for making Very Rapid Fluctuations in Polymer-Solvent Perturbed Angular Correlation (PAC) measurements. Interactions." Low concentrations of linear polymers One apparatus, which has been in operation for 16 years, can greatly reduce drag in various types of fluid transport.

measures four coincidences concurrently using cesium Although scientists have identified many drag-reducing fluoride detectors. A second spectrometer was acquired polymers, investigators have not been able to observe 12 years ago, and it measures four coincidences directly the polymer-solvent interactions causing drag concurrently using barium fluoride detectors. A third reduction. For this purpose, Professor Catchen is using spectrometer was set up eight years ago to accommodate PAC spectroscopy.

the increased demand for measurement capability. The detectors and electronics provide a nominal time The PAC technique is based on substituting a radioactive resolution of I nsec FWHM, which places the probe atom such as I I I In or 1 8 1 Hf into a specific site measurements at the state-of-the-art in the field of in a chemical system. Because these atoms have special Perturbed Angular Correlation Spectroscopy. nuclear properties, the nuclear (electric-quadropole and magnetic-dipole) moments of these atoms can interact Penn State has a unique research program that uses PAC with the electric field gradients (efg's) and hyperfine Spectroscopy to characterize technologically important magnetic fields produced by the extranuclear electrical and optical materials. This program represents environment.

the synthesis of ideas from two traditionally very different branches of chemistry; materials chemistry and Static nuclear electric-quadropole interactions can nuclear chemistry. Although the scientific questions are provide a measure of the strength and symmetry of the germane to the field of materials chemistry, the PAC crystal field in the vicinity of the probe nucleus. In the technique and its associated theoretical basis have been case of static interactions, the vibrational motion of the part of the fields of nuclear chemistry and atoms in the lattice isvery rapid relative to the PAC radiochemistry for several decades. The National timescale, i.e., 0.1-500 nsec. As a result, the measured Science Foundation and the Office of Naval Research efg appears to arise from the time-averaged positions have sponsored this program in the past. of the atoms, and the sharpness of the spectral lines reflects this "motional narrowing" effect. In contrast to static interactions, time-varying interactions arise when the efg fluctuates during the intermediate-state lifetime. In solids, these interactions can provide information about defect and ionic transport. In liquids these interactions can provide information about, for example, the conformations of macromolecules such as polymers. The effect of the efg fluctuating in either strength or direction, which can be caused, for example, by ions "hopping" in and out of lattice sites or by molecules tumbling in a solution, is to destroy the orientation of the intermediate state. Experimentally, this loss of orientation appears as the attenuation or

"'smearing-out" of the angular correlation. And, often a correspondence can be made between the rate of attenuation and frequency of the motion that produced the attenuation.

Magnetic hyperfine interactions, which can be measured in ferromagnetic and antiferromagnetic bulk and thin-film materials, are used to study the mechanisms that cause the transition between the magnetically-ordered phase and the disordered phase.

Figure 1. Prof.Catchen inserts a sample into a high-temperature samplefurnace, which is mounted in the Current laboratory research is detailed in Section XII center of the four-detector array of the perturbed- of this report.

angular-correlationspectrometer.

39

ENVIRONMENTAL HEALTH & SAFETY Xir\I/ I

.j ,

A(,Il I'

40

ENVIRONMENTAL HEALTH & SAFETY Environmental Health and Safety (EHS) is an active participant in ensuring the overall safety of the Radiation Science and Engineering Center (RSEC) operations. The RSEC and EHS are committed to the health and safety of the environment, public, students and employees. EHS is responsible for the overall administration of the radiation safety program for Penn State. The University is licensed by the U.S. Nuclear Regulatory Commission (NRC) to receive, acquire, possess, and transfer byproduct material (radioactive material produced by a nuclear reactor), source material (naturally occurring radioactive material, uranium compounds), and special nuclear material (radioactive material that has the potential to undergo nuclear fission) and to operate the Breazeale Nuclear Reactor at the Radiation Science and Engineering Center. The College of Engineering has administration responsibility for the reactor operations license (R-2 license).

The ALARA radiation protection philosophy, keeping the radiation exposure as low as reasonably achievable, is the basis for the RSEC and EHS radiation protection and safety programs. Both groups collaborate to maintain the highest level of health and safety programs necessary for the administration of nuclear programs and compliance with federal and state regulations.

Figure 2. Greg Herman of radiationprotection Services provided to the RSEC fall into the following surneys around the GammaCell 220 Excel Irradiator.

categories: "ALARA" programs, customer service, licensing and regulatory requirements, and training.

ALARA PROGRAMS This year EHS performed over 134 radiation surveys at the RSEC. Survey results showed that there were no radioactive contamination surveys or radiation surveys above established limits and radioactive material was being handled in a safe and controlled manner. The surveys were conducted to detect possible transferable contamination from radioactive materials work or to survey radiation sources such as activation products, sealed sources, equipment, and reactor operations. The radioactive contamination surveys are performed in laboratories where radioactive materials are used and in the balance of the RSEC's public areas to ensure that no radioactive material has been transferred to these areas.

Both the contamination surveys and the radiation surveys are redundant to the surveys performed routinely by the RSEC staff. The redundancy of the contamination and radiation surveys is fundamental to the University's ALARA program.

EHS staff regularly attend scheduled RSEC operation meetings. The meetings provide a forum for participants Figure 1. Mark Linsley of radiationprotection to review the current reactor operations and experiments.

surveys samples in a laboratory. This active participation has established an open line of communication between the RSEC and EHS. Input by the radiation protection staff has contributed to the facility's safety and ALARA programs.

40

21L SERVICE LICENSING AND REGULATORY REQUIREMENTS EHS is responsible for the shipping and transfer of radioactive materials (RAM) to customers of the RSEC. During the past year Eric Boeldt, Penn State's radiation The U.S. Nuclear Regulatory Commission and U.S. safety officer (RSO), and Candace Davison (RSEC)

Department of Transportation mandate complex renewed the NRC license for the Co-60 pool. Final requirements for the packaging, shipping and transfer of approval was received in January of this year; the license radioactive materials. EHS facilitated eighteen shipments is now valid until 2014.

of RAM for RSEC customers. Customer support Dosimetry requirements are administered by EHS and included packaging and shipping Ar-4I and Na-24 forTru- dosimetry is issued to RSEC personnel to measure staff, Tec Inc., Ar4 I for Synetix Inc. and Na-24 for NWT Inc. student, and worker radiation exposures. This year EHS The shipping and transfer of radioactive materials issued a total of 564 dosimeters to RSEC personnel, includes the disposal of reactor radioactive waste there were no exposures above unsafe levels.

materials. Administration of the dosimeter program includes issuing dosimeters, processing dosimeters and From September to November, EHS personnel provided maintaining all dosimetery records. EHS has support for ten shipments of Pathfinder fuel off campus. administered a thermal neutron dosimeter program to In July RSEC received a new Co-60 irradiator. EHS check exposures more accurately for those working personnel were present to perform the necessary around the neutron radiography laboratory. One neutron incoming and setup surveys. dosimeter is a permanent fixture in the laboratory, and individuals wear the others as they work in the lab. A total of 68 thermal neutron dosimeters were monitored with no indication of any measurable thermal neutron exposures to personnel. Self-reading dosimeters are issued to transient persons and visitors to the RSEC.

The information for the temporary dosimetry is documented in logbooks maintained by the administrative staff at the facility. The RSO is an active member of the Reactor Safeguards Committee.

Training Training programs provided by EHS to the RSEC are license and regulatory driven. Training covering the requirement of shipping limited quantities of radioactive material was given to three reactor personnel this year.

Also, approximately 43 new reactor personnel and Figure 3. Dave Bertocchii of r(lwJiation protection students attended the radiation safety orientation.

andl TIhierrv Daubenspeck, senior reactor oweratoi; Required retraining for all radiation workers was load a shipmnent of RAL.

provided to the RSEC by means of a newsletter distributed to all laboratory supervisors. All RSEC personnel also completed the annual Chemical &

Chemical Waste Refresher Training. Three new employees and students attended the initial Chemical &

Chemical Waste Training program. The RSEC has a history of being in compliance with Penn State's Chemical & Chemical Waste Handling programs.

41

RADIATION SCIENCE &

ENGINEERING CENTER RESEAR CHAND SERVICE UTILIZATION

RSEC RESEARCH & SERVICE UTILIZATION Research and service continues to be the major focus of the RSEC. A variety of research and service projects are currently in progress as indicated on the following pages. The University-oriented projects are arranged by department in Section A. Theses, publications, papers and technical presentations follow the research description to which they pertain. In addition, Section B lists users from industry and other universities.

The reporting of research and service information to the editor of this report is the option of the user and therefore the projects in Sections A and B are only representative of the activities at the facility. The projects described involve five technical reports, presentations or papers, 36 publications, six master's theses, and two doctoral theses. The examples cited are not to be construed as publications or announcements of research. The publication of research utilizing the RSEC is the prerogative of the researcher.

Appendix A lists all university, industrial, and other user of RSEC facilities, including those listed in Sections A and B. Names of personnel are arranged under their department and college or under their company of other affiliation. During the past year, 47 students and staff members, 37 graduate students, and 24 undergraduate students have used the facility for research. This represents a usage by 13 departments or sections in five colleges and one research unit ofthe University. In addition, 53 individuals from 28 industries, research organizations, or other universities used the RSEC facilities.

SECTION A. PENN STATE RESEARCH UTILIZING THE FACILITIES OF THE RSEC Mechanical and Nuclear Engineering Department NE 444. REACTOR OPERATIONS LABORATORY

Participants:

C.F. Sears, Professor and Director, RSEC NE 444 is a one credit laboratory course which provides students the opportunity to individually operate the Penn State TRIGA Reactor and perform selected reactor experiments including checkout, approach to critical, numerous startups, power operations in manual and automatic control, power coefficient measurements, rod worth measurements both manually and with a reactor computer, square wave operations and pulse operations. This brings a hands on application to their analytical and theoretical class work.

NE 450, UNDERGRADUATE LABORATORY-RADIATION DETECTION AND ME EASUREMI ENT

Participants:

R.M. Edwards, Professor J.S. Brenizer, Professor C.F. Sears, Director, RSEC T.L. Flinchbaugh, Associate Director for Operations M.E. Bryan, Research Engineer B.J. Heidrich, Research Assistant Services Provided: Laboratory Space, Machine Shop, Electronics Shop, Reactor Instrumentation and Support Staff The Nuclear Engineering 450 course is the first of two 3-credit laboratory courses required of all Penn State nuclear engineering undergraduates and is typically taken during the Spring of the junior year. Each weekly laboratory exercise consists of two lectures and one laboratory session. NucE 450 introduces the student to many of the types of radiation measurement systems and associated electronics used in the nuclear industry as well as many of the mathematical techniques used to process and interpret the meaning of measured data. The radiation instruments studied in this course include GM detectors, gas flow proportional counters, Nal (TI) detectors, BF3 counters, ion chambers, wide range GM detectors and surface barrier detectors. The data collection and analysis techniques studied include radiation counting statistics, gamma ray and charged particle spectroscopy, and the interfacing of computers with nuclear instrumentation.

The wide range GM detector and BF3 detector are studied in the Cobalt Irradiation Facility. Ion chambers are studied with the reactor.

NE 451, UNDERGRADUATE LABORATORY OF REACTOR EXPERIMENTS

Participants:

R.M. Edwards, Professor C.F. Sears, Director, RSEC T.L. Flinchbaugh, Associate Director for Operations M.E. Bryan, Research Engineer B.J. Heidrich, Research Assistant Services Provided: Laboratory Space, Machine Shop, Electronics Shop, Neutron Irradiation Using Subcritical Pile, Reactor Instrumentation and Support Staff The Nuclear Engineering 451 course is the second of two 3-credit laboratory courses required of all Penn State nuclear engineering undergraduates and is typically taken during the Fall of the senior year. Each weekly laboratory exercise consists of two lectures and one laboratory session. By the beginning of the senior year, the students have already covered the LaMarsh Introduction to Nuclear Engineering text including reactor point kinetics. The 451 course emphasizes experiments using the instrumentation that was covered in NucE 450 and is divided into two "tracks". These tracks can be coarsely described as TRIGA and non-TRIGA experiments. The non-TRIGA track includes three graphite pile experiments.

42

In 2003, the TRIGA track included:

I. Digital Simulation of TRIGA Reactor Dynamics

2. Large Reactivity Insertion (Pulsing)

3. Control Rod Calibration

4. Reactor Frequency Response

5. Neutron Noise

6. Reactor Control

7. Source Affects and Feedback The laboratory utilizes Macintosh computers with GW Electronics MacAdios Jr. data acquisition hardware and Superscope I1 software. The Superscope 1l software was a major software upgrade for 1993, and witl its new point-by-point seamless mode enabled effective reactivity calculations and control experiments. The Mathworks SIMULINK simulation software was used for the digital simulation exercise for the first time in 1992. Reactor control is offered as a graduate course in our department but our undergraduates do not receive a complete introduction to feedback control. The reactor control experiment interfaces a general purpose PC computer to an Experimental Changeable Reactivity Device (ECRD).

Control experiments make use of one of two ERCD's implemented as a moveable experiment where an aluminum tube containing an absorber material is positioned within the central thimble of the reactor. The first ERCD with a worth of approximately SO.35 has a maximum insertion rate of about $0.12/s while the second with a worth of about S0.94 may be inserted up to $0.35/s. ERCD #1 is used for experiments of up to 65 percent where temperature changes produce significant reactivity changes. ERCD #2, added in 2000, is for use at low power (less than 0.1 percent) where temperature change and its reactivity effect are negligible. The SIMULINK Real Time Workshop is used to implement an experimental control algorithm. The SIMULINK automatic C code generation process produces and downloads the necessary real-time program for execution in a microprocessor-based controller with an ETHERNET network interface to the host workstation.

The 1994 version of the control experiment thus unified all of the MATLAB/ SIMULINK instruction earlier in the course into a demonstration of state-of-the-art CASE-based control system design and implementation.

NEUTRON II IRADIATrE) Si LICONE CARBIIID)E STUI)lE) USING POSITRON ANNI II LXHION LIFE'rTlME SPIECTROSCOIPY

Participants:

G. Catchen, Professor A. Motta, Professor C. Tyree, Graduate Student C. Trivelpiece, Undergraduate Student A. Dulloo, Westinghouse Electric Corporation F. Ruddy, Westinghouse Electric Corporation Services Provided: Neutron Irradiation, Gamma Irradiation Monitoring, Machine Shop, and Laboratory Space Sponsor: FERMI Group in conjunction with Westinghouse Electric Corporation Chris Tyree (MS student) and Cory Trivelpiece (undergraduate) are conducting research on silicone carbide wafers that are being considered for radiation detection equipment, under the supervision of G. Catchen and A. Motta. The semiconductor material is very resilient at high temperatures and could be used inside the pressure vessel of commercial reactors, but its performance degrades over time under neutron flux. The research project's main focus is on what kinds of defects are caused by neutron irradiation and at what temperature will the sample anneal and return to a defect-free state. Operation at this temperature would mean self-anneal of the devices and no degradation. Irradiation of the samples is conducted at the Breazeale nuclear reactor facility along with the analysis and annealing of the samples. Analysis of the defects present in the samples after post-irradiation annealing is performed using Positron Annihilation Lifetime Spectroscopy. The research is funded by the FERMI group and is done in conjunction with Westinghouse Electric Corporation.

Masters Thesis:

Tyree, Chris, "Neutron Irra(liatedtSilicon Carbid1e Stuliedl Using Positron Annihilation Lifetime Spectroscopjn" Advisors: G. Catchen, A. Motta 43

STUDY'OFAWATER DISTRIBUTION AND TRANSPORT IN A POLVNIER ELECTROLYTE FUELCELL USING NEUTRON IMAGING

Participants:

M. Mench, Assistant Professor J. Brenizer, Nuclear Engineering Program Chair and Professor K. OnlM, Professor P.A. Chuang, Post Doctoral.

N. Pekula, Graduate Student A. Turhan, Graduate Student K. Heller, Graduate Student Services Provided: Neutron Beam Laboratory Sponsor: General Motors Corporation, RSEC INTRODUCTION Due to its high efficiency, low operating temperature (-30-800 C), and rapid evolution since over the past decade, the polymer electrolyte fuel cell (PEFC) is currently under intense research and development. Compared to present power systems, such as the internal-combustion engine, fuel cells are advantageous for several reasons and present a promising future. The operating efficiencies can reach as high as 50-90% for units and also pollutants such as nitrous oxides and particulate matter are eliminated, while carbon dioxide and carbon monoxide are reduced to near zero.

Figure I shows the basic operation of a hydrogen PEFC. Hydrogen is supplied to the anode of the fuel cell while oxygen, usually taken from the air, is supplied to the cathode. The electrochemical oxidation reaction at the anode produces hydrogen ions and electrons.

Gas Diffusion Layer Anode 21-2 4 4-

• 4e 4e-Electrolyte I4H - ( a Cathode 2H20 v- 4H1 + 02 + 4e-Gas Diffusion Layer Figure 1: Simplified Schematic of PEFC The flow of the electrons through an external circuit powers a load. The ions produced at the anode are transported through an ionically conductive polymer electrolyte to the cathode, where water is produced. A 20 gm platinum catalyst layer is typically employed at both electrodes to reduce the activation energy for the electrochemical reactions.

Covering each electrode is a 200-400 pm porous carbon fiber gas diffusion layer (GDL). The GDL functions to enable reactant transport to, and product from the catalyst layer, while providing conductivity for electron transport.

In a PEFC, the level of water must be precisely balanced. Adequate water vapor must be available to maintain high electrolyte ionic conductivity and ensure suitable performance. However, if excessive water is present in the liquid phase, it can block pores in the catalyst and GDLs, hindering the transport of reactants to the catalyst. This phenomenon is known as "flooding", and greatly diminishes cell performance. Due to the delicate balance between the benefit of saturated flow and the deleterious effects of flooding concomitant with liquid water accumulation, there is extensive ongoing research to more fundamentally understand two-phase water transport in PEFCs, to enable performance and design optimization.

44

Although there have been numerous models presented in literature that predict the water production and transport phenomenon in fuel cells, there has been little research in experimental visualization and quantification of the liquid water distribution and transport. Neutron radiography and radioscopy are excellent non-intrusive techniques for visualization and quantification of the two-phase flow within the fuel cell in real time or steady-state.

EXPERIMENTAL SETUP The neutron radioscopy system and thermal neutron beam from the Breazeale Nuclear Reactor at the Penn State Radiation Science and Engineering Center was utilized in this study. Specialized image processing hardware was developed for the analysis, storage and presentation of the collected images.

An integrated test station at the Neutron Beam Lab (NBL) was built to control and monitor the fuel cell operating parameters. The NBL Test Station (NBLTS) is isolated from the neutron beam source, as illustrated in Figure 2. The station can accommodate various sized fuel cells (up to 22.8 cm diameter in a single frame) for neutron imaging processes while the following conditions are controlled by the operator on the station's control panel:

• Gas flow rates

• Inlet gas temperature and humidity

• Cell temperature

• Current/Voltage draw

• Operating pressure

• Nitrogen purge The visualization and quantification of the water distribution in the fuel cell is performed by neutron radioscopy and radiography techniques. Data acquisition and data presentation details for these techniques are described in the next section of this report.

NR Beam Source Concrete Wall LI1 Beam Catcher

/ Camera Gas Inlets Enclosed NR Beam Cave Gas Inlets Condenser Unit Test Stand . E 2 I ,*l*

Beam Catcher Gas Exits PEMFC Exhausted to Atmosphere Figure 2: Test station for fuel cell imaging at the NBL 45 Cocp

~1 ~~I

NEUTRON RADIOGRAPHY RESULTS '

A series of neutron radiographs were collected using the fuel cell and imaging setup. The cell temperature (80'C) and gas flow back pressure (0.274 MPa) were maintained constant throughout the experiments whereas the relative humidity of the anode and cathode were maintained at 100 percent at 800C forall tests. Figure 3 shows substantial wateraccumulation near the fuel cell exit (lower left corner) for radiographs taken at the low current density condition, i.e. 0.05 A/cm2 . The images show liquid water occupying a large portion of the gas flow channels causing channel flooding inside the fuel cell. From the flow channel geometry (2-channel pass design on anode and 3-channel design on the cathode) it can be concluded that the liquid water is on the anode side of the cell.

Figure 4 shows three separate radiographs taken at the high current density condition, i.e. 1.0 A/cm2 . The images show that highly dispersed liquid droplets are present in the lower half of the fuel cell, and that the flow channels near the cell inlet (upper third) contain almost no liquid water at all. This is most likely due to the water vapor being continually added to the gas flow stream along the flow channel path via generation until saturation. Through the cell exit, water accumulation is observed due to liquid saturation of the gas flow.

,, r S S - _ =-d wui.

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=. _ rests i a) 0,':*- >-at  ::---:  :! ll b) t.

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Figure 3: Neutron radiographsa) A =10.0; 2.5 A; 0.843 V b)=6.5; 50 A; 0.857 J' c)=6.0; 2.5 A; 0.868 V a)  ;

I 11"AMMEMEMELI:-.1111 I -

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Figure 4. Neutron radiographsa)=2.0; 5O A; 0.725 K b)=1.4; 50 A; 0.625 1' c)=1.3; 50 A; 0.600 V 46

REAL-TIME NEUTRON RADIOSCOPY RESULTS Real-time (30 fps) neutron radioscopy video of the operating fuel cell was recorded for a wide variety of test conditions.

Video was recorded for approximately 20 minutes for each experiment. The high temporal resolution of the radioscopy procedure allowed for the liquid water accumulation and transport in the cell to be directly observed. Further image analysis gave insight into the characteristics of the liquid water droplet behavior and flow velocities.

The results of velocity measurements indicate that the droplet velocity cannot be assumed to be on the same order of magnitude as the gas flow velocity for the fuel cell configuration and conditions tested, and a homogeneous, no-slip model of the two-phase channel flow is inappropriate for channel level two-phase modeling.

CONCLUSIONS Neutron radiography and radioscopy yield excellent spatial and temporal resolution for the investigation of water transport phenomenon and the measurement of liquid water inside an operating polymer electrolyte fuel cell. The results showed that the amount of water accumulation in the flow channels highly depends on current density. It was also shown that channel-level liquid droplet velocity is not constant, and changes substantially due to interactions with the flow channel walls and other droplets. The maximum velocity of the droplets are an order of magnitude less than the reactant gas flow.

REFERENCES I. N. Pekula, K. IHeller, P.A. Chuang, A. Turhan, M.M. Mench, J. S. Brenizer, K. OnMU, " Study of Water Distribution and Transport in a Polymer Electrolyte Fuel Cell Using Neutron Imaging,' Nuclear Instrumentation Methods, Section A. (Accepted for publication) 47 Il

NEUTRON RADIOGRAPHY MNEIASUREMIENTS OF WATER TRANSPORT IN AN OPERATING PENI FUEL CELL

Participants:

M. Mench, Assistant Professor J. Brenizer, Nuclear Engineering Department Chair and Professor K. 0nl0, Professor P.A. Chuang, Post Doctoral N. Pekula, Graduate Student K. Heller, Graduate Student A. Turhan, Graduate Student S. Soung, Schreyers Honor Undergraduate Student Services Provided: Neutron Radiography, Laboratory Space, Machine Shop Sponsor: Auto Manufacturer, S150,000 Many automotive companies are developing fuel cell systems as a high efficiency, low emissions technology for automobile propulsion. Proton exchange membrane (PEM) fuel cells combine hydrogen and oxygen to produce electrical current and only water and heat as by-products. The proper management of the water produced in the cathodic oxygen reduction reaction is essential to efficient fuel cell operation. The polymer membrane in the fuel cell must be well hydrated to facilitate proton transfer, but if too much water is present, flooding will occur which restricts reactant oxygen from reaching catalytic sites at the membrane surface. Also, because flooding affects the temperature gradients in the plane of the proton-conducting membrane, it is suspected that the phenomenon can impact the long-term durability of the fuel cell.

The sponsor is actively developing measurement methods that will aid in assessing all aspects of fuel cell operation for automotive applications. However, ascertaining where liquid water is generated within the fuel cell, and how it is transported on both the anode and cathode sides, remains a difficult experimental problem. Perhaps the only method available for measuring full-area water distribution in an operating fuel cell is the neutron imaging technique. Penn State University (PSU) has developed a high level of expertise in this field, and has reported previous experimental work on the application of neutron imaging to measure liquid water distributions in metallic enclosures. This project will examine water distribution in operating PEFCs.

Masters Thesis:

N. Pekula, "Visualization and Measurement of Water Accumulation and Transport in an Operating PEFC Using Neutron Imaging", M. S. Thesis, Spring 2004.

Reports to Sponsor:

Pekula, N., Onl, K., Brenizer, J., and Mench, M. M. 2003. Neutron Radiography Measurements of Water Transport in an Operating PEM Fuel Cell. Final 2003 Report to General Motors Invited Talks:

N. Pekula, M. M. Mench, K. Heller, K. Onilli, and J. Brenizer "Neutron Imaging of Two-phase Transport in a Polymer Electrolyte Fuel Cell," American Nuclear Society Spring Meeting, 2004.

M. M. Mench, "Advanced Diagnostics for PEFCs," Gordon Research Conference on Fuel Cells, Bristol, Rhode Island.

July 2004.

M. M. Mench, "Two-phase Flow Visualization in PEFCs-using Neutron Radiography to visualize and quantify liquid water transport in the diffusion media and flow channels of a PEFC.", 2004 International Conference on Fuel Cells, Taiwan, R.O.C., 2004.

48

M. M. Mench and N. Pekula, "Neutron Imaging of Fuel Cells," United Technologies Research Center, Connecticut.

February 2004.

Other Technical Presentations:

Pekula, N., Heller, K. Cetiner, S. M. Brenizer, J. Mench, M. M. and WUnlK. 2004. Neutron Imaging and Quantification of Water Distribution and Transport in a Polymer Electrolyte Fuel Cell. International Topical Meeting on Neutron Radiography ITMNR-5, Germany.

wIsTnIBUTEI) DIAGNOSrICSANI) VISUA.LIZAT,1ON OF POLYNIER ELECTROLYTE FUELCEIL, IPERFORMANCE D)URING FI1EEZE-TllAkVCYCLING Participatnts: M. Mench, Assistant Professor J. Brenizer, Nuclear Engineering Department Chair and Professor K. Onlio, Professor S. Soung, Schreyers Honor Undergraduate Student Services Provided: Neutron Radiography, Laboratory Space, Machine Shop Sponsor. Automotive Manufacturer, $800,000 for 4 years The vision of the newly started project is a comprehensive four-year characterization study of polymer electrolyte fuel cell phenomena during freeze-thaw cycling. This break- through study wvil be conducted using the advanced distributed diagnostic capabilities uniquely available at the Penn State Fuel Cell Dynamics and Diagnostics Lab (FCDDL). The project consists of the following major tasks, Task 2 is relevant to the radiation science and engineering center (RSEC):

Task 1. Ilighly detailed distributed performance measurement and analysis of freeze-thaw cycling including current, species, temperature, and high frequency resistance (HFR) data.

Task 2. Freeze-thaw frozen and liquid water visualization and mass distribution quantification and analysis with Neutron Imaging.

Task 3. In-plane and through-plane thermal transport characterization for thin-film PEFC materials using micro and/or nano-sized thermocouple sensor technology.

Task 4. Ph.D. study and training of auto company personnel at Penn State.

49

NEUTRON RADIOGRAPHY MEASUREMENTS OF WATER TRANSPORT IN PEFCs

Participants:

M. Mench, Assistant Professor J. Brenizer, Nuclear Engineering Department Chair and Professor K. onla, Professor P. A. Chuang, Post Doctoral K. Heller, Graduate Student A. Turhan, Graduate Student Services Provided: Neutron Radiography, Laboratory Space, Machine Shop Sponsor: Auto Manufacturer, $75,000 This project is to develop measurement methods that will aid in assessing all aspects of fuel cell operation for automotive applications. WVe seek to elucidate liquid water transport phenomena in the diffusion media (DM) and flow channels of an operating polymer electrolyte fuel cell. However, ascertaining where liquid water is generated within the fuel cell, and how it is transported on both the anode and cathode sides, remains a difficult experimental problem. Perhaps the only method available for measuring full-area water distribution in an operating fuel cell is the neutron imaging technique.

Penn State has developed a high level of expertise in this field, and has reported previous experimental work on the application of neutron imaging to measure liquid water distributions in fuel cell apparatus.

Liquid water visualization is of primary interest in two-phase model development and visualization, as well as design optimization. Several different phases of research are envisioned to achieve the ultimate goals summarized in Table I below. In general, the long-term object is to visualize the generation and motion of liquid water within the DM with sufficient spatial and temporal resolution to capture the dynamic accumulation and motion of liquid in the DM.

Table 1: Long Term Neutron Imaging Goals of Program Step/Specifications Experimental Program Envisioned Step I (this year): Space Water quantification and analysis with two different TMC Fuel resolution - 150 gim, time Cells and Evaluation of Imaging Tools (CCD camera, TMC resolution 30 Hz imaging system, and radiograph with Penn State software system)

Step 2: Space resolution Computed Tomography and Additional Experimentation to 50 lim, time resolution 30 Hz visualization of liquid growth accumulation, and motion in the DM Step 3: Space resolution Visualization of two-phase flowv dynamics within the DM with 50 gm, time resolution 200 Hz enhanced spatial and temporal resolution.

50

SOFT ERROR ANALYSIS TOOLSET (SEAT) DEVELOPMENT

Participants:

V. Narayanan, Prof. of Computer Science and Engineering Dept.

M. J. Irwin, Prof. of Computer Science and Engineering Dept.

K. OnHu, Prof. of Mechanical and Nuclear Engineering Dept.

Y. Xie, Prof. of Computer Science and Engineering Dept.

S. Cetiner, Ph.D. student at Mechanical and Nuclear Engineering Dept.

V. Degalahal, Ph.D. student at Computer Science and Engineering Dept.

F. Alim, Ph.D. student at Mechanical and Nuclear Engineering Dept.

Services Provided: Neutron Beam Laboratory Sponsors: Radiation Science and Engineering Center, Department of Computer Science and Engineering INTRODUCTION Soft errors, or single event effects (SEE), are transient circuit errors caused due to excess charge carriers induced primarily by external radiation. Radiation, directly or indirectly, may induce localized ionization that can flip the internal values of the memory cells. The major radiation source that causes this temporary malfunction in semiconductor devices is the cosmic rays.

Figure 1. A 65-nm DRAM (left) G Current and a schematic that conceptualizes the soft error phenomenon (right): Electron-hole pairscreated through ionization by radiationmight get drawn to node terminals before they recombine in the substrate causing a transientglitch in the device node. This temporary pulse might flip the internal state of the memory bit.

I1B Cosmic ray particles have the ability to either toggle the state of memory elements or create unwanted glitches in combinational logic that may be latched by memory elements. As supply voltages reduce and feature sizes become smaller in future technologies, soft error tolerance is considered a significant challenge for designing future electronic systems. For example, a I GB memory system based on 64Mbit DRAMs has a combined error rate of 3435 FIT (failure in 109 hours0.00126 days <br />0.0303 hours <br />1.802249e-4 weeks <br />4.14745e-5 months <br /> of operation) when using single error correction and double error detection. An even higher soft error rate of 4000 FIT was reported for a typical processor with approximately half of the errors affecting the processor core and the rest affecting the cache. Such errors also affect the fast growing FPGA (Field Programmable Gate Array) segment. are becoming a major component of modern societies.

As earth's atmosphere shields most cosmic ray particles from reaching the ground and charge per circuit node used to be large, SEE on terrestrial devices has not been important until recently. The galactic flux of primary cosmic rays 51 CO7 I

(mainly consisting of protons) is very large, about 100,000 particles/m2 s as compared to the much lower final flux (mainly consisting of neutrons) at sea level of about 360 particles/m 2 s [1]. Only few of the galactic particles have adequate energy to penetrate the earth's atmosphere. However, with continued scaling of feature sizes and the use of more complex systems, soft errors in terrestrial applications are becoming an increasing concern and have drawn attention since late 1990s.

The issue of SEE was first studied in the context of scaling trends of microelectronics in 1962 [2]. Interestingly, the forecast from this study that the lower limit on supply voltage reduction will be imposed by SEE is shared by a recent work from researchers at Intel [3]. However, most works on radiation effects, since the work in 1962, focused on space applications rather than terrestrial applications.

Figure 3. Top: Cosmic rays have two major origins: Primary cosmic rays are produced and accelerated by stellarflares, supernova There have been various documented failures due to soft errors ranging from explosions (left),pulsars, and explosion of memories used in large servers and aircrafts to implantable medical devices galactic nuclei Solar cosmic rays (right) like cardiac defibrillators [4]. A widely cited soft error episode involves L2 are the particles In the solar wind caches with no error correction or protection that caused Sun Microsystems' originating In the Sun. Bottom: Particles flagship servers to crash suddenly and mysteriously [5]. This problem resulted from primary sources travel the space and enter the earth's atmosphere. Fewer than in loss of various customers for Sun Microsystems. More ominous than this 1% ofthe primaries can make it to the failure can be errors in embedded devices such as cardiac defibrillators that ground, and they are mostly third- to are becoming an integral part of our society. As computing systems develop seventh-generation cascade particles.

into indispensable part of various critical applications ranging from medical implants to fly-by-wire aircrafts, immunity against soft errors becomes more critical for the society as a whole.

The importance of dealing with the soft error problem can be evidenced by the large number of papers and articles that flooded the scientific community over the last decades. However, most researchers are impeded by access to realistic fault models and real soft error data. This limitation results from confidentiality of soft error data of chips tested by semiconductor companies and the limited access to accelerated soft error testing facilities for academics.

Most commercial soft error testing in U.S.A. is performed at the Los Alamos test facility, access to which is expensive and cumbersome due to security clearances required.

THE IMPETUS BEHIND THE SOFT ERROR ANALYSIS TOOLSET (SEAT)

Radiation-induced SEE may seem to be easily solved through techniques such as radiation-hardened processing. These kinds of countermeasures have been traditionally and successfully adopted to remedy radiation effects in space applications. However, they are not suitable for commercial manufacturers of terrestrial devices as many of the solutions consume more power, reduce manufacturability and severely influence IC performance [6]. Even space applications are moving away from the use of radiation hardened process technology. They are using commercial off-the-shelf components that employ soft error protection techniques at software and architecture level for cost and performance reasons. As a result, many researchers have been focusing on employing new soft error countermeasures ranging from process to software levels.

52

Advances in process technology such as adoption of silicon-on-insulator (SOI),

elimination of boron-10 impurities are expected to mitigate the soft error problem to a certain extent. However, solutions at higher levels are still essential for reliable operation of the computing system. The lack of fault models that abstract the physical phenomena of soft errors accurately in a fashion that is accessible to computer engineers and the absence of tools that analyze the effectiveness of soft error countermeasures are affecting researchers in their quest for taming the soft error problem.

There is an obvious need for a community resource for researchers and industrial practitioners studying radiation-induced SEE on computing systems. Existing tools either do not address the problem in full extent or they are kept confidential by the sole proprietorship of commercial entities, and therefore Figure4. A sample 3D model used in are not available to the research community. The SEAT will serve a critical MCNP modeL Red cells representp purpose in providing researchers of electrical, computer, information sciences wells (boron doped), yellow cells or nuclear origin with an open, modular, flexible yet a comprehensive tool.

representn wells, and transparent blue silicon. The geometry and the number of cells can be altered wit regardsto the device to be modeled. The SEAT has emerged as a complementary tool to furnish theoretical This allowsfor simulatingmultiple foundation to experimental radiation-induced soft error research at Penn State upsets in adjacentcells caused by a Breazeale Nuclear Reactor by mechanical and nuclear engineering, and single particle. computer science and engineering departments. More details can be found in

[7] in this annual report. The experiments performed are compiled into an "accelerated soft error testing dataset". The researchers are then able to seek to duplicate these observations by the SEAT or vice versa.

The strength of the SEAT is the fact that it is built upon the combined expertise of computer and nuclear engineers. The SEAT hierarchy starts with modeling the ionization effects of particle strikes on semiconductor devices, and then creates higher-level abstractions of these effects for analysis at the circuit and architecture level. This infrastructure will enable researchers working on circuit, architectural and software countermeasures for soft errors to obtain a better perspective of the physical phenomena, and help them tune their techniques accordingly. If the fault model used at architecture or circuit-level fails to model the SEE accurately, the underlying value of solutions proposed at higher abstractions become meaningless.

53 B

IMPLEMENTATION OFTHE SEAT CODE BUNDLE The SEAT code bundle has a hierarchical structure as shown in Figure 5. Information collected at each level is relayed to one upper level for analysis.

Neutron transport constitutes the basis of the lowest-level analysis of the toolset. The creation of neutron-induced charged particles is simulated at this stage of the analysis. We chose MCNP5 to perform the neutron transport simulation. MCNP5 is a very powerful Monte Carlo code and comes with an extensive set of utilities. Figure 4 shows geometry that we used for the multi-bit SEE analysis in memories. The transparent blue material corresponds to bulk silicon, and red and yellow cubes are boron- and phosphorus-doped p and n wells, respectively.

Zone ofImpact Typical Circuit Structure Figure 5. Theflow, diagram of the SEATcode bundle. Informationcollected at each level is transferredto the next simulatorto be analyzed.

54

The MCNP output is analyzed and the reactions that ultimately end up in creation of charged particles are collected.

These ions are saved into a file in a format that is compatible with the next code, TRIM [8], at that level of analysis.

TRIM is another Monte Carlo code that simulates ion transport in solid media. TRIM accepts 3D ion distribution as input. Since it is given the same geometry as MCNP, it simulates the behavior of ions that come out of the neutron-induced reactions. The analysis of ion tracks gives as to what point in the medium the energy will be deposited. This is a first-order approximation to ionization caused by the charged particle transport, and is known as the Bragg approximation.

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Once the list of ions induced by external radiation and position of charges deposited is obtained, then the simulation of the phenomenon in device level can be performed. Figure 6 shows the output of a sample simulation performed with TCAD. In the figure, color contours represent the electron concentrations, and the line contours correspond to equipotential lines. Ion strike is initialized at time I psec. Before the ion strikes, equipotentials are parallel to the junction. The sequence of plots show that the charge column widens by the outward diffusion of carriers. The charge column also pinches off at the junction due to collection of charge from the depletion region. At time I psec, the equipotentials begin to extend into the substrate due to the voltage drop along the charge column. After a time the funnel starts to collapse and the drift current starts to decrease as charge is swept away from the depletion region. At 100 psec, the depletion region is effectively restored and only diffusion charge collection occurs.

55 I

CONCLUSIONS AND FUTURE WVORK The SEAT seems to fill a critical need, particularly in research community. With its current stage, it received a great deal of interest from both the academia and industry. We received many positive critiques in a conference that we presented the SEAT the first time [9]. Many industry affiliates stated their interest in the tool.

Even though neutrons account for the majority of the cosmic particles at sea level, the contribution of other particles, particularly protons, become dominant to the soft error problem at higher altitudes. For a more through analysis and more extensive applicability, other particle interactions should also be incorporated into the simulation. At this stage of the tool, we managed to include proton flux in the cosmic rays into the analysis. This, however, does not include nuclear-level interactions of protons with the medium, but it does take into account their direct ionization effect. For better modeling of physics, nuclear interactions of protons with the host nuclei must be accounted for since this dominates proton-related single-event effects.

The problem can be tackled by using medium-, high- and very high-energy intranuclear cascade codes, which simulates particle reactions within the nucleus between the particle and nucleons based on nucleon-to-nucleon cross sections.

Addition of a cascade code will extend the capability of MCNP, which, with the current cross section library, can support up to 150-MeV incident neutron energy. Cross sections for incident neutron energies beyond 150 MeV is extrapolated.

The nuclear cascade codes, however, can simulate interactions for particle incident energies even beyond I GeV.

REFERENCES

1. J. F. ZIEGLER, TerrestrialCosmic Ray, Intensities, IBM Journal of Research and Development, v. 40, No: 1, pp. 19-39, 1996.

2. J. WALLMARK, S. MARCUS, Minimum Size and Afaximum Packaging Density of Non-redundant Semiconductor Devices, Proceedings of IRE, 50, 1962.

3. S. BORKAR, T. KARNIK, V. DE, Design and Reliability Challenges in Nanometer Technologies, Proceedings of 41" Design Automation Conference, San Diego, 1994.

4. P. D. BRADLEY, E. NORMAND, Single Event Upsets in Implantable CardioverterDefibrillators, IEEE Trans. Nucl.

Sci., v. 45, pp. 2929-2940, Dec. 1998.

5. Sun Microsystems, Soft Mfemory Errors and Their Effect on Sun Fire Systems, 2002.

6. P. E. DODD, L. W. MASSENGILL, Basic Mechanisms and Modeling of Single-event Upset in DigitalMicroelectronics, IEEE Trans. Nucl. Sci., v. 50, pp. 583-602, June 2003.

7. N. VIJAYKRISIINAN, M. J. IRWIN, K. UNLO, V. DEGALAIIAL, S. M. QETINER, Testing Neutron-induced Soft Errors in Semiconductor Memories, Breazeale Nuclear Annual Report, December 2004.

8. J. F. ZIEGLER, http://Nvww.srim.org/

9. V.DEGALAIIAL, S. M. CETINER, F. ALIM, N. VIuAYKRISHNAN, M. J. IRWIN, K. UNLO, SESEE: A Soft ErrorSimulation and Estimation Engine, 7' Int. Conf. on Military and Aerospace Programmable Logic Devices (MAPLD), September 8-10, 2004.

56

NEU'FRON IMAGING SYSTEM ,IPIROVE.NIENTS

Participants:

J. Brenizer, Prof. of Mechanical and Nuclear Engineering Dept.

M. Mench, Prof. of Mechanical and Nuclear Engineering Dept.

K. OnlO, Prof. of Mechanical and Nuclear Engineering Dept.

R A. Chuang, Ph.D., Mechanical and Nuclear Engineering Dept.

K. Heller, Graduate Student A. Turhan, Graduate Student Services Provided: Neutron Beam Laboratory Sponsors: DOE- INIE, RSEC and NINE INTRODUCTION The growing demand for dynamic neutron imaging (radioscopy), especially for fuel cell research, has placed new requirements on our existing neutron imaging capabilities. These included developing a more efficient means of data acquisition and storage, better post processing techniques, and a more accurate quantification of water present in the radioscopic images. To this end, the neutron imaging team at the Radiation Science and Engineering Center (RSEC) has made several fundamental and very advantageous changes to its equipment and software resources. The following sections describe the recent upgrades to our imaging and post-collection image processing systems.

EQUIPMENT UPGRADES For many years our dynamic imaging system consisted of an analog camera connected to a computer through an analog-to-digital interface card that allowed the capture of 30 fps images at 640x480 and 8-bit grayscale depth. This system provided a stable foundation to support the development of data capturing and post processing procedures. To meet the requirements for our recent fuel cell research, a "turn-key," completely digital, image acquisition system was added.

Purchased through the company "I-Cubed," the complete system is comprised of a Pentium IV computer system with camera interface card, a Cohu CCD Camera and image capture software. The computer system is exceptional for both storage of the large volumes of digital image data being captured during radioscopy experiments and the running of the in-house developed, post processing and water quantification software. The digital CCD Cohu camera supplied with the system has a 1004x 1004 pixel resolution and a 10-bit deep grayscale range. When connected to the computer's interface card, frame rates as high as 30fps are possible. The unique driver set and onboard buffers of the Epix interface card make this possible.

Norpix's Streampix image acquisition software was included with the computer. Image capturing and storage is done in the form of proprietary image stacks called "sequence files," which can then be exported to a variety of fonmats, most notably TIFF and AVI. All post processing is done in the TIFF format since it a lossless image format and can be read on PC, Macintosh or Unix computers. AVI files are convenient when a qualitative, "real-time" inspection of an object is desired. The saved image sequence file can be converted to the AVI movie format and played back on Quicktime or Windows media player without the need for secondary movie conversion software.

The Streampix software also includes the ability to run user-written plug-ins. This feature allows the synchronization of image capture with external devices through the serial port or external data acquisition cards. Capturing an image along with a pressure or temperature reading is now possible, as well as capturing an image at the request of an external device, such as a rotation table signaling proper test subject alignment.

The decision to use a "turn-key" system was based on the desire to avoid incompatibilities between the various hardware components. An added advantage of the "turn-key" system is the accompanying tech-support, which can troubleshoot problems and provide quick solutions.

57 Il

POST PROCESSING SOFTWARE UPGRADES The Penn State neutron imaging team has focused on developing in-house software for data analysis. PSUMagic is the latest incarnation of the PSU Frame Grabber software originally designed for use with the older analog imaging system.

With high-speed digital image capture now accomplished through Norpix's Streampix, an earlier version of PSUMagic was modified to enhance its post-processing and water quantification algorithms.

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.IW P.aus as tiiatte~d canvai aftu PSU Magic Main Window Several post-process image enhancement techniques were incorporated to increase the overall image quality and accuracy of the water quantification process.

To account for the random noise in sequential images, the luminance value of corresponding pixels within sequential images can be averaged. This process improves image quality and makes liquid water accumulation and movement more discernible, albeit at the expense of temporal resolution.

Minor fluctuations (typically <<1%) in the reactor power level are common during experiments, resulting in changes in the neutron beam flux and consequently the corresponding measured pixel luminance values in a captured image. By monitoring a reference location on each image that is recorded, the beam intensity between each frame is determined and the entire image is normalized accordingly. The reference is a static location, such as the fuel cell backing plate, outside the active area where pixel luminance should be theoretically constant throughout the length of an experiment.

This procedure is referred to as "Reactor Power Normalization".

The PSU Magic software can correct for variations in the intensity of the neutron beam across the image plane using a beam normalization technique (sometimes called "flat-fielding"). By examining a blank image (only the uninterrupted neutron beam), the average pixel luminance value is determined. The acquired average value is divided by each individual pixel luminance value of the blank image to produce a corresponding correction factor for each pixel. The correction factor matrix is then multiplied by each image recorded during actual experiments to produce a "flattened" image making the initial beam intensity uniform.

Several other image enhancement techniques to improve qualitative analysis have also been added. These are also very useful highlighting water levels in presentations of single images or video clips. These include false colorization of liquid water in the fuel cell to make it more discernible and a technique that produces an image of only liquid water in the cell. This procedure is referred to as "Water Attenuation Map Isolation" or "Water Isolation."

58

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The ability to store individual images digitally allows for easy post-process analysis including ascertaining pixel luminance values of features in the image, such as water within a fuel cell. Consequently, the determination of water content within a cell as a function of time is attainable by referencing a pre-generated calibration look-up table that correlates water thickness to pixel luminance. This table is generated using a water-filled calibration wedge that duplicates the neutron attenuation and scattering effect of the fuel cell. The wedge is the exact distance from the beam port aperture as the fuel cell to ensure the equal beam intensity and hence measured attenuation as the fuel cell.

The wedge contains a water-filled channel of continuously varying thickness. The steady and gradual decrease in pixel luminance from the bottom to top of the wedge is representative of the increasing water thickness level within the wedge. This luminance data can then be referenced to assign water thickness values to individual areas within the cell or the entire cell as a whole. The mass and volume of water in the cell can then be computed for finite instances or as a varying function of time This method works well in this application because the water thickness are at most I mm, and they are typically less than 250 lgm. Thus, there are essentially no multiple neutron scatters.

The water quantification procedure was confirmed using an aluminum block milled with channels of known width, height and thickness, filled with water and exposed to the neutron beam where radioscopic images were captured. The post processing and water quantification procedures were applied and the measured values showed good agreement with the theoretical values.

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_a.n Test Block Water Attenuation Imaie FUTURE INNOVATIONS Refinement of water quantification in neutron imaging is ongoing. Future experiments will determine the minimum thickness of water the system can see and measure. The look-up table method of analysis will be replaced with a fitted equation providing more accuracy.

A Neutron Computed Tomography (CT) system is being developed to compliment our neutron imaging capabilities. The CT system will make use of recent software developments such as the cross sectional reconstruction software, Octopus, and the volume 3-D image generation software, VGStudio Max.

61

NEUTRON BEAMI CHARACTERIZATION OF THE BREAZEAI.E NUCLEAR REACTOR AT TIHE PENNSL'tX'ANIA STATE UNI'ERSIT'. RSEC

Participants:

J. S. Brenizer, Nuclear Engineering Program Chair and Professor K. Only, Professor C. Trivelpiece, Graduate Student Services Provided: Neutron Beam Laboratory Sponsor: Department of Energy, Innovations in Nuclear Infrastructure and Education (INIE)

Neutron beams are used in a variety of experimental methods at research reactors all across the United States. Such applications include: neutron radiography and tomography, neutron depth profiling, neutron diffraction, etc. The aforementioned techniques employ neutron interactions, which are characterized by energy dependent cross sections.

Accordingly, information characterizing the energy spectrum of these neutron beams is useful.

The current method being used for neutron Raw counts per channel spectroscopy at the Breazeale Nuclear Reactor is a time-of-flight (TOF) method using a slow neutron 10000 chopper that was brought from Cornell University, 9DOO Ward Center for Nuclear Sciences. The TOF technique is based on measuring the time it takes neutrons to travel C 7000 a predetermined distance. For this experiment, we 6MD measure the amount of time it takes for neutrons to travel from the aperture of the slow neutron chopper C 4000 itself (Figure 1), to a lithium loaded glass detector.

When the reactor is at power, a collimated neutron beam is incident on the chopper slit that can be seen in 1000 io Figure 1. Inside the chopper device, a disk rotates and low essentially fragments the incident neutron beam. Every channels Frotation of the disk triggers an optical sensor that signals the beginning of the TOF measurement. The TOF measurement is completed for given neutrons when neutrons enter the detector and produce pulses. A computer program is used that provides the ability to measure multiple channels (corresponding to multiple neutron flight times) for each rotation of the chopper disk.

The neutron spectrum is obtained from a multi-channel scaler (MCS) and each channel in the collected spectrum corresponds to specific neutron energy. Figure 2 is a typical energy spectrum collected using the current experimental setup. The neutron energy spectrum detectable with this particular system ranges from 0 - 0.3 eV.

Currently, work is being done to make the slow neutron chopper system portable so that the system can be used at other research reactors. The original chopper setup consisted of the chopper, a collimating tube, detector and detector shielding. Also, multiple nuclear instrumentation modules (NIM) and bins needed for pulse processing and data analysis.

62

Recently, equipment was purchased to accomplish the goal of making the analysis portion of the chopper system portable. The new equipment includes:

• Canberra Portable Bin/Power Supply (Model 1000)

• Canberra Multiport 11 MCA/MCS

• Canberra High Voltage Power Supply (Model 3102D)

• Dell Latitude D600 Notebook PC Two ORTEC instrumentation modules (Spectroscopy Amplifier and an SCA) are used in the signal processing; however, these modules were also used in the original setup. The original MCS was located on a PCI card and required a computer with an open PCI slot for operation.

The Multiport 1IMCA/MCS device uses an internal analog- Figure 3: Neutron collimator tube and detector to-digital converter (ADC) and a USB connection to shielding connect to the Dell notebook, eliminating the need for a PCI card based MCS as well as a desktop computer with an open PCI slot. The Multiport 1I works like any other nuclear instrumentation module in that it is compatible with any NIM bin. This compatibility, coupled with the USB connection capability, makes the Multiport 11 one of the key pieces in making the slow neutron chopper system portable.

The design of the experimental setup (slow neutron chopper, collimator tube, detector and shielding) must also be redesigned in order to make the slow neutron chopper system portable. To accomplish the goal of being able to ship the system to other research reactors, system components must disassemble and reassemble with ease, and still meet their experimental needs.

Currently, the slow neutron chopper is mounted on a stand which keeps the chopper slit at a constant height corresponding to the height of the neutron beam. The collimator and the detector (w/

shielding) are aligned so that the slit and the detector are at the same height. The original system will be redesigned to give the components adjustable heights, so that the system can be used in different nuclear research reactors. The distance from the front of the collimator tube to the back of the detector shielding is approximately 2.5 meters (Figure 3). This length poses a problem Figure 4: Proposedpolyethylene / borated when considering shipping methods. The collimator tube will be aluminum shielding annuli redesigned into sections, probably three, that can be easily attached together while keeping the strict alignment tolerances needed for this experiment. The detector shielding must also be redesigned for shipping purposes. One idea being discussed involves machining polyethylene and borated aluminum annuli, in which the detector will be placed (Figure 4). The polyethylene will be wrapped with boroflex to provide additional neutron shielding. Shipping cases and packing material will be purchased to complete this stage of the project.

To date, two experimental runs have been made at a reactor power of 850 kW. The first run was made with the original system (desktop PC, PCI based MCS card) to ensure that the system was properly aligned in the beam. Upon completion of this run, the detector was immediately connected to the new equipment (Multiport 11, Dell notebook), and a second neutron energy spectrum was collected. The two spectra were compared and found to be similar, implying that the new equipment is suitable for use in this experiment. Experimental runs at different power levels will be made in the near future.

63 C" I I

As mentioned earlier, the detectable neutron energy range for the slow neutron chopper system is 0 - 0.3 eV. It is desirable to measure the higher end of the neutron beam energy spectrum. An ORTEC Model 525-780 Helium-3 Neutron Spectrometer has been ordered which will allow neutron energy spectrum measurements of both thermal and fast neutrons. This spectrometer utilizes the 3He(n,p) 1 H reaction. The incident neutron energy is determined by measuring the energies of the proton and the triton which are produced during the reaction. Shipping cases and materials will also be purchased so the helium-3 spectrometer can be shipped along with the slow neutron chopper system to characterize the energy spectrum of other neutron beam facilities.

Progress is being made to make the neutron beam characterization equipment portable, and extend the detectable energy range of the current setup. When completed, the slow neutron chopper system, combined with the helium-3 spectrometer, will make a useful tool for characterizing the energy spectrum of neutron beams at many research reactors across the United States.

64

TESTING NEUTRON-INDUCED SOFT ERRORS IN SEM\IICONDUCTOR MIENMORIES

Participants:

N. Vijaykrishnan, Professor M. J. Irwin, Professor.

K. Oniy, Professor V.Degalahal, Ph.D. Student S. M. Cetiner, Ph.D. Student Services Provided: Neutron Beam Laboratory Sponsor: DOE, INIE, Big-Ten Consortium Mini Grant Program INTRODUCTION Soft errors are transient circuit errors caused due to excess charge carriers induced primarily by external radiations.

Radiation directly or indirectly induces localized ionization that can flip the internal values of the memory cells. Our current work tries to characterize the soft error susceptibility for different memory chips working at different technology node and operating voltage.

BACKGROUND AND RELATED WORK Advances in VLSI technology have ensured the availability of high performance electronics for a variety of applications.

The applications include consumer electronics like cellular phones and HDTVs; automotive electronics like those used in drive-by-wire vehicles, and million dollar servers used for storing and processing sensitive and critical data. These varied applications require not only higherthroughput but also dependability. Even if a microprocessor is shipped without any design errors or manufacturing defects, unstable environmental conditions can generate temporary hardware failures.

These failures, called transientfaults, cause the processor to malfunction during operation time. The major sources of transient faults are electromagnetic interference, power jitter, alpha particles, and cosmic rays. Studies in [1, 2] have shown that a vast majority of detected errors originate from transient faults. Even a single-bit error may eventually lead to a computation failure. Therefore, managing the soft errors is a critical problem to solve in fully realizing dependable computing.

Soft error rate (SER) testing of devices has been performed for both neutron and alpha particles. Beam 30L of Weapon Neutron Research at the Los Alamos National Laboratory is a JEDEC prescribed test beam for soft errors, and is the only one of its kind. This beam is highly stable and it closely replicates the energy spectrum of terrestrial neutrons in the 2-800 MeV range while providing a very high neutron flux.

The SER testing reported in literature recently were performed at this facility [4, 5]. However, the beam availability is limited. Alternatively in the past, experiments were carried out with alpha particles originating from 238Th foil on 0.25 pm-generation SRAMs [7]. Elimination of borophosphosilicate glass (BPSG) and '0B from the process flow in the 180-nm generation has made the low-energy (<1 MeV) neutron SER negligible [3]. High-energy (1-1000 MeV) neutrons often dominate SER in advanced CMOS logic and memories. Hence, the need for accessible neutron testing facilities is critical for design of the next generation igure 1. Test chip as seenfrom the narrow opening semiconductor semiondutor evics.

devices. i the polyethy lene/lead shield.

This study intends to observe the effect of '0B and high energy neutrons on soft error rate. In order to investigate the effect of Boron-1O on SER, a thermal neutron beam is used. For high-energy neutron testing, we intend to use the fast neutrons available near the reactor core by inserting a test circuit into a stand-up pipe adjacent to the reactor core face. This setup is shown in Figure 2.

65

• 1

1. Neutron Beam Port

2. Tt __rd BoaE 3 ethlne/lead shield with opening Figure 2. (Left) Simplified layout of the test board, beam tu an reactor.p as seen from the narrowopening in the polyethylene/lead shield.

EXPERIMENTAL SETUP AND RESULTS Penn State Breazeale Nuclear Reactor was used as the neutron source in the experiments. The maximum rated power of the reactor is I MW in the continuous mode, and 2000 MW in the pulse mode. The reactor power is adjusted from 10 W to IMW observe the soft error rate dependence on neutron flux. No pulse-mode operation has been performed. Figure b To Pool side I and 2 show the test chip and the experimental setup. Reactor Bridge - monitoring Shield plug For the beam port that was used in the experiments, the beam support tube looks at the D2 0 tank to get a well-thermalized beam. ,- Irradiation Pipe The average thermal flux at the exit of the beam port is about 3x10 7 neutrons/cm sec. The high neutron flux allows for Water pool accelerated testing of the phenomenon.

The experimental setup consists of a custom board interfaced *- Shield Plug with a computer through a GPIB card (from National Instruments). The board itself has off-the-shelf SRAM memory chips. The board is controlled through a LabVIEW interface. The controlling application consists of simple routines to read and write a user specified value across the Cable whole memory. During the readout, it compares the written value to the value in each address.

Core Cadmium Layer The circuit board is secured in the beam cave, and connected

.I to a PC outside using a 25-ft cable. This configuration Test Board allowed for continuous read-write, and for changing the operating conditions without interrupting the experiment. ..............................................

The selected section of the board is tested on-line multiple Figure 3. Fastneutron test setup near the reactor times in the actual setup before the reactor is started. The core.

board is exposed to neutron flux after the reactor reaches the stable power level.

66 C}

I

As mentioned earlier, the neutron flux around the reactor core is much higher than that at the neutron beam ports.

Therefore, the circuit board will also be placed by the periphery of the reactor core via a vertical standpipe in order to observe the effect of fast neutrons on soft error rate. A schematic drawing of fast neutron irradiation facility at PSBR is shown in Figure 3. The fast neutron flux at the core boundary is 5x10' 2 neutrons/cm 2 sec, and thermal flux is 1.3xI0' 3 neutrons/cm 2 sec at IMW steady state reactor operation. The reactor can be pulsed for a very short duration of time, around 10 milli-sec at its Full-Width Half-Maximum, at which it generates a fast flux of about lxlO'6 neutrons/cm2 sec at the core periphery. This amounts to about a ten order of magnitude increase in the fast flux. The time duration is very limited, yet the amount of fast flux is immense. The test circuits will be let inside the standpipe and the reading will be taken. In addition, the walls of the pipe will be covered with cadmium. Cadmium will absorb the thermal component of the flux so that the board is affected only by fast neutrons.

RESULTS AND DISCUSSION The setup described in this report allows for accelerated neutron testing of semiconductor memory devices. Currently, one memory chip from Cypress Semiconductor was tested across multiple runs. The chip is rated to operate at 5V, but found to operate as low as 3V. We found the chip to have 15 errors after testing for one hour at 3V, but had only 2 errors at 5V for the same time period. Similar experiments were also conducted using a Toshiba Chips memory. This confirms the exponential dependence of soft error rate on device operating voltage as pointed out by several authors before [7].

Table I presents the details from these experiments.

Table 1. PreliminaryAccelerated Soft Error Testing Data Chip Operating S ERib Voltage 5V 2 CY7C I 28A-20PC, 16 kbits 3V 15 5V 57 TC554001AFT7L. 4 Mbits 4V 638 FUTURE WVORK This report briefly summarizes the first phase of the study that focused only on the effect of '0B fission caused by thermal neutron absorption on soft error rate. The elimination of BPSG layer in new device technologies and considerable reduction of '0B content in the p-dopant significantly dropped the contribution of boron fission as a source of soft error.

Therefore, for younger-generation technologies, one needs to take into account the high-energy neutron impact on device operation for proper soft error rate analysis.

In the later phase, the circuit will be placed by the periphery of the reactor core in order to observe the effect of fast neutrons on soft error rate. The fast neutron flux at the core boundary is 5xl0' 2 neutrons/cm 2 sec, and thermal flux I.3x10'3 neutrons/cm 2 sec at I-MW steady state reactor operation.

The reactor can be pulsed for a very short duration of time, around 10 msec at FWHM, at which it generates a fast flux of about lxlO1' 6 neutrons/cm 2 sec at the core periphery. This amounts to about a ten order of magnitude increase in the fast flux. The time duration is very limited, yet the amount of fast flux is immense. That might also reduce the experiment times significantly and help perform more tests with various technologies and designs.

67

REFERENCES

1. J. SOSNOWSKi, Transientfault tolerance in digital systems, IEEE Micro, v. 14 No. 1, pp. 24-35, February 1994.

2. D. P. SIEWIOREK, R. S. SwARTZ, Reliable Computer Systems: Design and Evaluation, 2nd edition, Digital Press, Burlington, MA.

3. R. BAUMANN, The impact of technology scaling on soft error rate performance and limits to the efficacy of error correction, IEDM '02 Technical Digest, IEEE International, pp. 329-332, 8-11 Dec. 2002.

4. P. HAZUCHIA, T. KARNIK, J. MAIZ, S. WALSTRA, B. BLOECIIEL, J. TSCIIANZ, G DERMER, S. HARELAND, P. ARMSTRONG, S.

BORKAR, Neutron soft error rate measurements in a 90-nm CAMOS process and scaling trends in SRAAI from 0.25-Ispl mu/in to 90-nm generation, IEDM '03 Technical Digest, IEEE International, pp. 21.5.1-21.5.4, 8-10 Dec.

2003.

5. J. MAIZ, S. HARELAND, K. ZIIANG, P. ARMSTRONG, Characterizationof iutlti-bit soft error events in advanced SRAA s, IEDM '03 Technical Digest, IEEE International, pp. 21.4.1-21.4.4, 8-10 Dec. 2003.

6. N. SEIFERT, D. MOYER, N. LELAND, R. HOKINSON, Historical Trend in Alpha-Particleinduced Soft ErrorRates of the Alpha Mficroprocessor, IEEE 39th Annual International Reliability Physics Symposium, pp. 259-265, 2001.

7. P. HAZUCHA and C. SVENSSON, Impact of CAfOS Technology Scaling on the Atmospheric Neutron Soft ErrorRate, IEEE Transactions on Nuclear Science, v. 47, No. 6, pp 2586-2594, Dec. 2000.

68

NEUTRON ACTIVATION ANALYSIS OFABSOLUTELY-DATED TREE RINGS

Participants:

K. Jnltl, Prof. of Mechanical and Nuclear Eng. Dept.

T. H. Daubenspeck, Activation & Irradiation Specialist D. K. Hauck, Ph.D. student, Mechanical and Nuclear Eng. Dept.

Services Provided: Radionuclear Applications Laboratory Sponsors: Cornell University, NSF, and RSEC INTRODUCTION The Dendrochronology project taking place at the Breazeale Nuclear Reactor is a search for heightened gold concentration in tree rings with the use of Instrumental Neutron Activation Analysis (INAA). The usefulness of this study lies in the environmental and climactic history that can be deduced from the data. Large amounts of stratospheric sulfur from volcanic eruptions, forest fires or industrial pollution can stress trees and result in larger heavy ion uptake. We are focusing on gold uptake because of its suitability to INAA. In addition, climate cycles over 1Os of years can be identified and correlated with such well-known cycles as the El Nino Southern Oscillation (ENSO) and the North Atlantic Oscillation (NAO). The current climatological record recording these cycles only exists for the past 100-150 years. This relatively short record makes Earth's climate cycles and effects like Global Warming difficult to understand. A correlation with ion uptake in tree rings would allow us to extend the climatological record back thousands of years.

PSU NAA FACILITY In the past year, the INAA facility was completed at the Breazeale Nuclear Reactor. This includes installing two Dry Irradiation Tubes (DT) in the reactor core, getting the Automatic Sample Handling System (ASHS) up and running, setting up the analysis system with a High-Purity Germanium (HpGe) Detector, a Digital Spectrum Analyzer and Genie-2000 software, and doing the flux measurements necessary to identify flux peak area for sample irradiation positions. Nearly 400 tree ring samples have been analyzed from a tree which grew in Turkey between the years 1473 and 1980 A.D. The tree rings that have been analyzed so far are from the years 1600 -

1980 A.D. We will first complete the analysis of this tree (1473-1980) and continue with a tree from the same @ Dry Tubes 1and 2 e Control Rods e Central Thimble region and covering similar time period. Figure 1. The Dry Tubes occupy positions E4 and E13 in the reactor core.

The Dry Tubes Two Dry Irradiation Tubes (DT) were installed in the reactor core for irradiation of NAA samples. The DT's occupy approximately symmetric positions within the core, as shown in Figure 1. The bottom of the DTs was designed to be identical to the bottom fuel rod tips and fit into the bottom grid plate. The height of the DTs are approximately 21 feet and bend to 6 inches off the centerline approximately one third of the way up. This allows for samples to be pulled out of the core while they decay but maintain a depth of 14 feet of water as a radiological shield.

69 C) Z_

CAL I

Flux measurements were performed in the DTs at 10 W, 800 kW and I MW show that the height of the flux peak is strongly dependent on the position of the control rods but fairly independent of core position within the reactor pool.

Measurements were done both in the center of the reactor pool position and coupled core-D O tank position. The peak flux at I MW was approximately 1.5 x 10"3 n/cm'/s with DTI being consistently slightly higher than DT2. The flux measured inside the polyethylene vials used for wood irradiations is approximately 1.2 x 10" nfcm'/s with the difference presumably the position of polyethylene vials and possibly from moderation by the polyethylene vial.

The Autoniatic Sample 11andling Systent (ASIJS)

The Automatic Sample Handling System (ASHS) brought from Cornell University, Wkard Center for Nuclear Sciences by Dr. Onlal was installed and tested at Penn State, RSEC. Batch programming files have been written specifically for the Dendrochronology project and for general I usage. This allows the user to define the number of samples to be run in S the ASHS in sequence and the amount of time that they are to be counted. i' Special presets can be used, for example real time vs. live time and files -

can be automatically named and analyzed according to user specified values. The ASHS holds up to 90 samples at one time, allowing for a consistent through put of sample especially useful for such an extensive study as the Dendrochronology project. A close-up picture of ASHS is 1 shown in Figure 2.

lipGe Detector A new HpGe detector was purchased, allowing the former HpGe detector 4 * - -

associated with the Dendrochronology project to be dedicated to teaching iSI and demonstrations. The new HpGe detector has a 36% relative efficiency and 1.8 keV resolution at the higher energy cobalt peak (1332 keV).

This has allowed for more accurate isotope identification and area calculations. The detector is surrounded by 3000 lbs of pre-WWII lead bricks to block out environmental background radiation.

Figure2. A close up picture of ASHA showing sample tray and robot arm.

Data Analysis Before irradiating wood samples, the natural radioactivity of the wood should be considered. In order to find the typical isotopes found in un-irradiated wood, and how their abundance differed in different tree rings, approximately 30 tree ring samples were analyzed. The samples that analyzed are from the years 1940-1968 and they are from a tree which grew in Turkey between 1628 and 1998. This measurement period corresponds to the heaviest years of nuclear weapons testing. Consistently the following isotopes were identified in tree samples: Ac"2S, Ral", U"35,Bi'" and Pa' 34.

Recent samples that have been analyzed since the inclusion of the new irradiation facilities in the Breazeale Nuclear Reactor are from a Turkish pine tree and range in date from 1600 to 1980. The average isotope concentrations differ slightly from another Turkish tree which was analyzed previously. A comparison of average concentrations of some isotopes for these trees is given in Table 1. The smaller quantity of Gold in the tree samples requires long irradiations or higher neutron fluences. At RSEC, the tree samples are irradiated at 4MW-hours for each batch of runs. In comparison, typical irradiations of tree samples were 1.2 MW-hours at Cornell University. This more powerful irradiation has allowed for the identification of a new isotope, La-139, which has promising qualities as an indicator of biological stress.

70

Table 1: Average concentrations of isotopes in twoTurkish trees spanning the years 1650 to 1980. The tree CTUCAT14C was analyzed recently at Penn State. CTUKLKIOB was analyzed previously at Cornell University. Differences may be due to different uptake properties of the two trees or different regional environmental stresses. Concentrations are in parts per million.

Isotope CTUCAT14C CTUKLKIOB Na-23 39.85 52.46 K-41 20.34 21.81 Mn-55 23.69 13.29 Zn-67 1.78 1.72 La-139 .019 N/A Au-198 .0055 .0078 The chronology of data from the samples recently analyzed is also promising. The data shows a clearly defined base continuum in the isotopes that will behave chemically as salts in the tree, especially including Sodium, Potassium and Bromine. This continuum indicates a steep rise around the late eighteenth century that may be due to increased industrialization, metabolism with in the tree or large time-scale climate cycles. Any of the three possible causes for this increase in background would be an important indicator for future studies. All identified isotopes show very strong peaks (as much as an order of magnitude higher) on top of the background continuum (see Figure 3). The peaks are very consistent among the salt-like isotopes and slightly different for the heavier, non-reactive elements like gold. This may be a result of active transport within the tree of chemicals that take part in the biological processes of the tree. Gold, on the other hand, is inactive and expected to have no active transport and very little passive transport across tree rings, making it ideal for this study. Three example isotopes are shown in Figure 3. Potassium, Zinc and Bromine behave similarly to Sodium. The data we are acquiring now is from another tree that grew in the same region of Turkey and covers the similar time period. We will be looking same trends for this tree in order to verify our previous observations.

CONCLUSIONS The tree samples that are currently being analyzed have great promise as an indicator of major environmental events in addition to climatic change and plant uptake properties. In particular, the comparison of Gold uptake properties with that ofthe salts should reveal which effects are due to tree biology and which are due to external stresses. The next immediate goal is to complete the analysis of several trees and make a correlation with environmental effects and the ion uptake behavior of trees.

71 In

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72 C2L31

TIM E-OF-FLIGHIT NEURON DEPTH PROFILING (TOF NDP) AT PENN STATE BREAZEALE NUCLEAR REACTOR

Participants:

K. Onla, Prof. of Mechanical and Nuclear Eng. Dept.

S. M. Cetiner, Ph.D. student at Mechanical and Nuclear Eng. Dept.

Services Provided: Neutron Beam Laboratory Sponsor: U.S. Department of Energy, under Nuclear Engineering Education Research (NEER) grant INTRODUCTION Neutron Depth Profiling (NDP) is a near-surface analysis technique to measure the spatial distribution of certain isotopes of technological importance in any substrate. The NDP technique was originally developed by Ziegler et al [1, 2] in 1972, and later thoroughly investigated by Biersack et al [3]. The basis of NDP is the irradiation of a sample with thermal or sub-thermal neutrons and the subsequent release of charged particles due to neutron induced exoergic charged particle reactions. Neutrons interact with the nuclei of isotopes '0B, 3 He, 6Li, 'Be and 22Na etc, and release mono energetic charged particles, e.g. alpha particles or protons, and recoil atoms. Table I gives a detailed listing of other relevant NDP reactions.

Table 1. Useful NDP Reactions Elesent Reaction Abundance Target Encrgy of Emitted C. Section D)etection Limitl n (%) Ilaiflife Particles (keV) (barns) (atoms/cm 2)

Li (Li (n, a) 'I1 7.5 stable 2055 2727 940 5.71 x 10" 7

Be 1Be(n, p) 7Li [2.5 x 10"]t 53 d 1438 207 48000 1.12 x 10" 7

B "'B (n,a) Li 19.9 stable 1472 840 3837 1.40 x 10" N "N (n, p) "C 99.6 stable 584 42 1.83 2.93 x 10" O '70 (n, a) "C 0.038 stable 1413 404 0.24 2.24 x lo" 22 2 6 Na Na(n,p)"Ne [4N4x.4 lO] t . y 2247 103 31000 1.73 x 10" 3

S S (n, a) "Si 0.75 stable 3081 411 0.19 2.83X 10x Cl 3CI (n, p) 35s 75.8 stable 598 17 0.49 lx 1.10 o' K 'K (n,p) 'Ar 0.012 stable 2231 56 4.4 1.22 x 10" Ni 39Ni (n,a) '6Fe 1.3 X 10 201t 80,000y 4757 340 12.3 4.37 x 10o6 The charged particles travel outward and lose energy by numerous interactions with the electrons of the host matrix.

Measuring the residual energy of the charged particles or recoil atoms and knowing the stopping power of the host matrix allow for the determination of the depth profile of the isotope of interest inside the matrix. The reader is recommended to refer K. Onlil et al [4-8] for a comprehensive discussion.

73 n

PRINCIPLES OF THE TOF NDP In conventional NDP, the residual energies of charged particles are measured directly by using silicon surface barrier, PIPS, or silicon PIN photodiode detectors. However, because of the 5%#Dne1 physics, there is an error inherent in the measurement process.

Conventional semiconductor detectors employ a dead layer at the entrance of the active area. The energy transfer in this layer brings statistical uncertainty to the energies of the charged particles, which are created at single energies and only have a distribution because of the thickness of the material of interest.

In TOF NDP, however, the residual energies of charged particles are not measured directly, but instead it is deduced based on the time-of-flight measurement spectrum.

The time-of-flight information of each particle is obtained from the time difference between the pulses generated by the start and stop detectors. The start detector is triggered by electrons that are sprayed out of the surface of the sample as a charge particle leaves the surface. This is almost a spontaneous process. Figure 1. Simplified schematics of the TOF NDP However, these electrons are ejected from the surface with very pynpgrimpntal Iph.n small energies and therefore they need to be accelerated for efficient signal processing.

An electrical field on the path of the particles accelerates electrons. The field is created between the sample plate and a specially manufactured sieve as seen on Figure 2. The micro-mesh structure on the sieves behaves both as a permeable anode surface and filter that eliminates electrons that move off the line of sight. The potential difference between the sample plate and the sieve, which we call "acceleration region", causes an electron to achieve very high velocities because of its miniscule mass. A conceptual schematics of the TOF NDP setup is shown in Figure 1.

An electromagnet steers electrons onto the start detector. Since the mass of electron is small, the amount of magnetic field required is also very Figure 2. Very fine-meshed siev, es are limited. This allows for selective particle transfer, i.e. focusing electrons manufacturedthrough a process called onto the start detector and letting recoils, proton or alphas go directly at electroform meshing.

the stop detector.

The signals generated by the two multi-channel plate (MCP) detectors have very high precision timing information.

These signals are fed into two fast-timing amplifiers that provide time discrimination. Originally, the signals that come out of the MCP's are current pulses. The output of the time discriminator becomes voltage pulses and also reshaped in order to make them compatible with the time-of-flight time analyzer.

Time analyzer is the central part of the time-of-flight analysis. It behaves like a multi-channel analyzer in time domain, where varying time differences constitute the time span of the spectrum. In order to do that, the time difference between the two signals is discretized. If the time analyzer reads a signal that falls into a discrete time channel, it increases the counter value associated with this particular channel by one. This way, a spectral distribution is created where the left-hand side of the spectrum represents the smallest time difference and hence the fastest traveling recoils.

74 M- M

PREPARING THE TEST SAMPLE FOR INITIAL EXPERIMENTATION Time-of-flight test system will ultimately be used in front of the reactor beam for industrial test samples, particularly from the semiconductor industry. However, preliminary experimentation with the system and at the earlier stages will require an adaptation process. In order to avoid unnecessary occupation of the nuclear reactor time, we decided to proceed with a test sample that will give a detectable depth profile to test the integrity and reliability of the setup. Once we become confident that the depth profile obtained by the time-of-flight setup is within the limits of expectations, we then plan to start to repeat the NDP experiments that were done with conventional methods.

The test sample will be a monoenergetic alpha source. Polonium- _

210 is an isotope that emits alpha particles single energy and not Figure 3. 3D drawing of the MCP detecs

.. .analysis holder. The assembly was designed and followed by any additional radiation. This alleviates the analyssmanufacturedat the Breazeale Nuclear Reactor of signals by the electronic circuitry. machine shop.

In order to get a depth distribution that will emphasize the functionality of the system, we decided to do a polonium-210 surface implantation on a thin silver foil. The electrochemistry between silver and polonium makes it possible to do surface implantation without employing sophisticated techniques. The affinity of silver to polonium forces polonium atoms to diffuse into a certain depth from the surface, but not get distributed homogeneously. This is done by putting the silver foil into an acidic polonium solution, in this case polonium-2 10. Because of the surface affinity in silver, polonium spontaneously deposits itself on the surface of the foil creating an alpha emitter depth profile.

SETTING UP THE TOF NDP SYSTEM Time-of-flight NDP system includes two multi-channel plate detectors (MCP), a vacuum chamber, vacuum pumps, and signal processing electronics.

Multi-channel plate (MCP) detectors are very sensitive devices that can easily become defective. We have MCP detectors that are high-precision that were purchased from Hamamatsu. However, we decided to use MCP's that have manufacturing fault but are still functional in order to avoid the expense of renewing the equipment. The detectors are provided to us by a professional affiliate of the project.

However, the MCP's that are given to us were bare MCP detectors without the assembly. We designed a modular assembly that can operate with various dimensions of MCP :

detectors and for high voltage levels. Figure 3 shows the 3D CAD drawing of the design.

We also upgraded the PC interface of the time analyzer Figure 4. 3D CAD drawing of the vacuum chamber with from an ISA-compatible card to a PCI-compatible card. the sample and two MCP detectors. Neutron beam shines This gave us the flexibility of using more up-to-date onto the sample containingboron-JOand depth profiling is computers and operating systems. obtained by analyzing the back emission spectrum.

Figure 4 shows a 3D CAD drawing of the vacuum chamber, two MCP detectors and the neutron beam. The drawing is a downscaled representation of the actual vacuum chamber.

75

The neutron beam enters the chamber through one of the thin aluminum windows and shine on the sample. The neutrons in the beam interact with boron-10 atoms and create alpha and lithium particles. The charged particles are emitted isotropically with respect to the original location of the isotope. From the back emission of recoils and electrons that are ejected from the surface along with recoils, we get the time-of-flight spectra of particles, as explained in more detail in the foregoing section.

-= - IFI -

Figure 5. Simplified schematics of the vacuum chamber, beam tube and the reactor The layout of the test setup in the reactor beam lab is shown in Figure 5. The vacuum chamber is placed in front of one of the beam tubes and is aligned with the neutron beam so that the beam crosses the sample as shown in Figure 4. During the experiment, the reactor core is placed by the D2 0 tank. When the reactor reaches the requested power level, the shutter is opened allowing the neutron beam to enter the chamber.

CONCLUSION AND FUTURE WORK As the technology progresses the size of the semiconductor devices go down significantly. The nominal device thickness until couple of generations ago was around 200 nm. Conventional TOF technique provided ample resolution for decent analysis. However, especially with the arrival of ultra-shallow junctions, the technology is now going towards device thicknesses below 90 nm. The resolution obtained by conventional NDP (- 15-20 nm) is obviously not a statistically adequate represen-tative of such figures. We anticipate a much higher resolution from TOF NDP, less than 5 nm, and this will make it possible to detect isotope profiles of thicknesses less than 100 nm.

76

ACKNOOWLEDG EMENT This project is sponsored by U.S. Department of Energy under Nuclear Engineering Education Research (NEER) grant DE-FG07-OOID- 13921.

REFERENCES

1. J. F.ZIEGLER, G. W. COLE, J. E. E. BAGLIN, J. Appl. Phys., v. 43 (1972), p. 3809.

2. W. K. CQiu, V. L. MORUZZI, J. F. ZIEGLER, J. Appl. Phys., v. 46, No. 7 (1975), pp. 2817-2820.

3. J. P. BIERSACK, D. FINK, R. HENKELMANN, K. MOLLER, Nuc. Inst. Meth., v. 149 (1978), pp. 93-97.

4. K. ONLO and B.W. WEIIRING, Nucl. Instr. And Afeth. Phys. Res. A, v. 353, (1994) p. 402.

5. K. UNLO and D. H. VINCENT, "Helium-3 behavior in some Nickel-based Amorphous Alloys," NuclearScience and Engineering, v. 110, No. 4, April 1992.

6. K. UNLO, M. SAGLAM, B. W. WEHRING, "3 He and "B Concentration and Depth Measurements in Alloys and Semiconductors using NDP," NucL. histr. and Afeth. in Phys. Res. A, v. 422 (1999) pp. 885-890.

7. K. UNLO et al., IEEE Proc. I I' nt. Conf. on Ion Imp. Tech., v. 1, 1996, p. 575.

8. S. M. CETINER, K. ONLO, R. G. DOWNING, 11" Int. Conf. on Modern Trends in Activation Analysis, University of Surrey, Gilford, UK, 2004 (Proceeding wvill be published in Journal of Radioanalytical and Nuclear Chemistry).

77

AUTOM,1ATED TIIREE-D'IMENSIONALMlONTE CARLO BASED DEPLETION MIEThIODOLOGY FOR PSBR CORE

Participants:

K. Ivanov, Professor C. Tippayakul, Graduate Student The research is focused on the application of the Monte Carlo techniques to the PSBR core calculation. The Monte Carlo code, MCNP5, is being employed to analyze the PSBR core. In addition, the ORIGEN2.2 code has been coupled with the MCNP5 code in order to introduce the depletion calculation capability to the PSBR core analysis code system.

The interfacing between the two codes is performed by a new developed code, TRIGSIM. The TRIGSIM code provides a convenient PSBR core analysis tool to the users since it automatically generates both MCNP input and ORIGEN input from a simpler TRIGSIM input. The MCNP input for PSBR core is generated based on the geometry and the fuel composition of each fuel element provided by the TRIGSIM input. Subsequently, the TRIGSIM code calls the MCNP code to execute the calculation and extracts the MCNP output to generate ORIGEN input. Finally, the TRIGSIM code calls the ORIGEN code to execute the calculation and extracts the ORIGEN output to generate MCNP input for the new burnup step. The current PSBR core loading 51 is being analyzed by the TRIGSIM code. The initial fuel composition of each fuel element is determined by utilizing the HELIOS-1.7 code to perform the burnup calculation up to the current burnup of each fuel element.

New developments will be utilized in the TRIGSIM code system in the future. These include the development of Monte Carlo acceleration scheme for PSBR core, the generation of burnup cross section library for TRIGA fuel types and the development of the coupled Monte Carlo/Nodal methodology to efficiently provide better spatial distributions of the PSBR core. Furthermore, the TRIGSIM code system will be employed to analyze the new PSBR core loading 52.

Master's Thesis:

C. Tippayakul, K. N. lvanov, C. F. Sears, G. M. Morlang and B. J. Heidrich, "Automated Three-dimensional Depletion Capability for the Pennsylvania State University Research Reactor", Proceedings of PHYSOR2004, April 25-29, 2004, Chicago, IL, USA.

78

AUTOMAkTEDTIIREE-DiMIENSIONAlMiNlONTE CARLO BASED DEPLETION METHODOLOGY FOR PSBR C:ORE

Participants:

K. Ivanov, Professor C. Tippayakul, Graduate Student The research is focused on the application of the Monte Carlo techniques to the PSBR core calculation. The Monte Carlo code, MCNP5, is being employed to analyze the PSBR core. In addition, the ORIGEN2.2 code has been coupled with the MCNP5 code in order to introduce the depletion calculation capability to the PSBR core analysis code system.

The interfacing between the two codes is performed by a new developed code, TRIGSIM. The TRIGSIM code provides a convenient PSBR core analysis tool to the users since it automatically generates both MCNP input and ORIGEN input from a simpler TRIGSIM input. The MCNP input for PSBR core is generated based on the geometry and the fuel composition of each fuel element provided by the TRIGSIM input. Subsequently, the TRIGSIM code calls the MCNP code to execute the calculation and extracts the MCNP output to generate ORIGEN input. Finally, the TRIGSIM code calls the ORIGEN code to execute the calculation and extracts the ORIGEN output to generate MCNP input for the new burnup step. The current PSBR core loading 51 is being analyzed by the TRIGSIM code. The initial fuel composition of each fuel element is determined by utilizing the HELIOS-1.7 code to perform the burnup calculation up to the current burnup of each fuel element.

New developments will be utilized in the TRIGSIM code system in the future. These include the development of Monte Carlo acceleration scheme for PSBR core, the generation of burnup cross section library for TRIGA fuel types and the development of the coupled Monte Carlo/Nodal methodology to efficiently provide better spatial distributions of the PSBR core. Furthermore, the TRIGSIM code system will be employed to analyze the new PSBR core loading 52.

Master's Thesis:

C. Tippayakul, K. N. Ivanov, C. F. Sears, G M. Morlang and B. J. Heidrich, "Automated Three-dimensional Depletion Capability for the Pennsylvania State University Research Reactor", Proceedings of PHYSOR2004, April 25-29, 2004, Chicago, IL, USA.

79

'II

PARALLEL TRANSPORT NIODEL BASED ON 3-D CROSS-SECTION GENERATION FOR TRIGA CORE ANALVSIS

Participants:

K. Ivanov, Professor N. Kriangchaiporn, Graduate Student C. Tippayakul, Graduate Student The purpose of this project is to develop reactor core physics model based on 3-D parallel transport methodology utilizing 3-D multigroup fuel lattice cross-section generation and core calculation. The resulting accurate and efficient calculation scheme is intended to be flexible in its application by using adaptive algorithms. The focus of the research is a new methodology for enhanced core physics simulation of the PSBR.

The new 3-D parallel transport calculation scheme for reactor core simulations is based on the PENTRAN code. The complete methodology includes development of algorithms for 3-D cross-section generation and modeling. This will solve several major weaknesses of the current reactor core analysis methodology (the diffusion approximation of the whole core calculations), the shortcomings of generation of multigroup cross section, and the approximations introduced with cross-section parameterization and functionalization.

At present, the fine- and broad- group structures for the TRIGA cross-section generation problems were developed based on the CPXSD (Contribution and Point-wise Cross-Section Driven) methodology in a 2-D fuel cell model. The parametric studies for SN calculations were performed to evaluate the impact of the spatial meshing, angular, and scattering order variables and to obtain the suitable values for cross-section collapsing and homogenization of the TRIGA cell problem. The DORT calculation shows that the meshing with 6132-mesh model, SIO quadrature order of Legendre-Chebychev technique, and PI scattering order are the appropriate model for our calculations. Utilizing the scalar flux weighting technique, the 18-broad group structure (18G) was collapsing from 279G with the CPXSD methodology. It was demonstrated that the broad-group library is in close agreement with its fine-group library, within 0.01% Ak/k. Also, comparing with the continuous energy Monte Carlo predictions, we have demonstrated that these new libraries yield good results, with deviations less than 0.08% Ak/k. In addition to cross-section group condensation, we also perform the cross-section homogenization. Compared to broad-group heterogeneous cross sections, the broad-group-homogeneous cross-sections results differed by -0.2% Ak/k.

Ph.D. Thesis:

N. Kriangchaiporn, K. Ivanov, A. Haghighat, and C.F. Sears (2003). "Parallel Transport Model based on 3-D Cross-Section Generation for TRIGA Core Analysis." A Docoral Thesis Proposal. In progress.

Publications:

N. Kriangchaiporn, K. Ivanov, C. Sears, G. Morlang, and B. Heidrich. (2001). Advanced Fuel Management Code System for the Pennsylvania State University Breazeale Reactor (PSBR). TANSAO. 85:415-417.

N. Kriangchaipom, K. Ivanov, A. Haghighat, and C. Sears. (2004). Multi-Group Cross-Section Generation for TRIGA Core Analysis. TANSAO.

80

MIODEIANG OF EXISTING BEAMNI-PORT FACILITYAT PENN STATE UNIVERSITY BREAZEALE REACTOR BY USING MICNP

Participants:

K. Ivanov, Professor Y.Azmy, Professor J. Brenizer, Nuclear Engineering Department Chair and Professor K. Onlt, Professor F.Alim, Graduate Student B. Sarikaya, Graduate Student Services Provided: Neutron Beam Laboratory Sponsor: DOE, Innovations in Nuclear Infrastructure and Education (INIE)

INTRODUCTION The Penn State University (PSU) Code System that has been developed to perform computer simulations of the beam port facility at the Reactor Science and Engineering (RSEC) at PSU consists of two major parts, the core model and the beam port model. The core model is needed to compute the flux at the reactor core - beam port facility boundary so that it can be used to compute the flux at the end of beam port where the experimental data were taken. Core calculations are performed by using the nodal diffusion code ADMARC-H[ 1]. The few-group cross section library needed to perform the diffusion calculations with ADMARC-H has been generated by the lattice physics code HELIOS [2]. The beam port calculations require very detailed geometrical definition of the system. This complexity of the geometrical model and the number of materials used in modeling the beam port facility prevent the use of deterministic codes in this study.

Therefore, because of its geometrical flexibility a general Monte Carlo N-Particle Transport Code, MCNP5 [3], is used in this study to model the beam port facility. The source distribution used in beam port model is taken from theADMARC-H code. An interface program has been developed at PSU to link the diffusion code to the neutron transport code. This interface reads the ADMARC-H output then computes the source term for MCNP and finally prepares the necessary MCNP input card in the requested format. The core model, the interface module, and the beam port model were described in RSEC 2003 annual report. Verifications of these models and applications of the tools developed for these models will be described in this report.

81

VERIFICATION AND APPLICATION OF THE PSU CODE SYSTEM Verification The results of the overall PSU Code Package, which contains the core model, the beam port model that consists of the D2 0 tank and the beam port tube models, and the interface module to link these two models are verified by comparing these results with the available experimental data [4] as shown in Figure 1.

41.O40

- -MCNP 3.GE* 06 -Experiment

3.0E408 I

F' Z.6E^4O S 2.0E40B E 1.6 4OB IO., .OE408 6.1407 OOE+-O0 q*

T 104M M

UAk Ct C0l - e4 eneog-y teov Figure 1: Comparison of the results of the PSU Code Package with the experimental data for the exit of the beam port #4. The solid curve represents the experimental data and the dashed line represents the model predictions with the associated error bars (the dotted vertical lines).

Applications After establishing the tools for the beam port design study, these tools were used to model beam port #7. Two different MCNP generated plots of the model are given in Figures 2.a and 2.b since beam port #4 and #7 are axially located at different elevations.

Figure 2.a: BP#7 @pz=7.0 cm plane Figure 2.b: BP #7 @ pz= 12.7 cm plane 82 If

Both figures show the top view of the system at different axial locations. Since both beam ports and the D 20 tank are cylindrical in shape, in both plots, their sizes differ at different elevations. The same methodology used in the BP #4 calculations was applied for the BP #7 calculations. The results of the D20 tank model for 9x 108 neutron histories with the associated statistical errors are shown in Figure 3.

3.5E+11 3.0E+11 2.5E+11

-2.0E+11 1.5E+11 X

0 1.0E+11 5.OE+ 10 O.OE+00 o - _

o 9 9 9 9 9 9 U LU LU LU LU LU 0 0 o U) 0 U) 0 o U) 6 _ N Xl energy (eV)

Figure 3: The D2 0 tank resultsfor BP #7 (all angles). The solid line represents the model predictions and the dotted lines represent the associated error bars (statisticalerror in the calculations)

This result represents the spectrum at the tallied surface for all angles. However, in order to prepare the input for the beam guide tube, a highly collimated neutron flux was needed. Therefore, the D20 tank model was designed to tally for this very highly collimated flux, and this study is still underway and has been running.

Even though the verification of the system was made for the neutron analysis, we turned on the gamma analysis option in the MCNP calculations and performed an analysis for the neutron induced gammas within the system (not core gammas).

Figure 4 shows the plot of the gamma spectrum at the beginning of the beam port guide tube (end of D2 0 tank model) for all angles.

83 c1b

CONCLUSIONS AND FUTURE WORK In this study, the existing beam port facilities at PSU Breazeale Reactor were modeled by using a code package developed at PSU, which consists of two major steps, the core calculations and the beam port facility calculations. The core calculations were performed by using the diffusion code ADMARC-H, which utilizes a few-group cross section library developed with HELIOS. MCNP5 was used to perform the beam port facility model calculations. The link between the core calculations and the beam port calculations was established with an interface program specifically prepared for this study.

3.0E-09 -

i2.5E 0.

to 2.0E-09 -

E E

co 1.5E a2 C) 1.OE E 5.OE-10 -J t&

0 C __ I A A

. -I

+ + 4 u W o o CNI w

a w 04 U,

o o energy (eV)

Figure 4: Gamma spectrum at the entrance of the beam port guide tube (BP #4)

The beam port #4 model was used to verify the PSU code package since the experimental data for this beam port and core configuration was available. The results presented for the beam port #4 model showed that the prediction of PSU code system agrees well with the available experimental data [5,6].

The same tools and methodology were used to simulate the beam port #7. Since beam port #7 is located 5" lower than beam port #4, which is exactly located at the axial centerline of the reactor core and since there is more D20 and an extra graphite block in between the beam port #7 and the reactor core, the number of neutrons that can reach up to the beam port #7 is much less than that of the beam port #4. Therefore, the statistics of the beam port #7 calculations were worse than that of the beam port #4 calculations for the same number of histories. Hence, beam port #7 calculations were performed for much longer histories.

REFERENCES

1. K.N. Ivanov, N. Kriangchaiporn, "ADMARC-H Manual"' the Pennsylvania State University 2000.

2. "HELlOS Methods", StudsvikScandpower, 2000

3. X-5 Monte Carlo Team, "MCNP - A GeneralMonte Carlo N-Particle Transport Code, Version 5, Volume 1:

Overview and Theory", LA-UR-03-1987, April 24, 2003

4. J.H.J. Niederhaus, "A Single-Disk-Chopper 77me-of-Flight Spectrometer for Thermal Neutron Beams", M.S.

Thesis, the Pennsylvania State University, University Park, PA (2003)

5. B. Sarikaya, "Modeling of Existing Beam Port Facility at Penn State Breazeale Reactor by Using MCNP5",

M.S. Thesis, the Pennsylvania State University, University Park-, PA (2004)

6. B. Sarikaya, F.Alim, K. Ivanov, J.Brenizer, K. Onla, and Y.Azmy, "Modeling of the Existing Beam Port Facility at the PSU Breazeale Reactor by Using MCNP", Proceedings of PHYSOR 2004, Chicago, April 2004, USA.

84

Anthropology Department NAA ANALYSIS OF PREIIISTORIC MIETARIIYOIITEARTIFACTS FROMD VIRGINIAAND MARYLAND

Participants:

K. Hirth, Professor G. Bondar, Ph.D. Candidate J. Fleming, Undergraduate Services Provided: Neutron Irradiation, Radiation Counters, Laboratory Space The goal of this research is to trace distinctive artifacts manufactured from metarhyolite to known prehistoric quarries in North Carolina, Virginia, Maryland, and Pennsylvania. The artifacts of the Broadspear Horizon form a distinctive and intrusive element from 4,000 to 3,000 years ago in the archaeological record of this region. However, explanations for this cultural discontinuity vary.

This project tests the hypothesis that the prehistoric culture which produced these artifacts spread from south to north through the study area. Results of NAA of 65 artifacts from twenty-one archaeological sites in Virginia, and eight others from Maryland, will be matched to the extensive database of characterized source material from previous research at Penn State's Breazeale Reactor. Preliminary statistical results suggest that a transition point from southern sources (NC and VA) to northern sources (MD and PA) exists in the study transect just north of the Rappahannock watershed in Virginia. While these results generally conform with those from a parallel study of artifact form, and appear to support the hypothesis, the final implications of these results remain to be determined.

Es3 Figure 1: Afetarhyolite broadspearfrom Watkins Ilsand, Maryland (44FXH) in the Potomac River.

85

'n

Figure 2: Afetarhyolite broadspearfrom the Robinson Collection (44AfCX32) along the Roanoke River in southern Virginia.

86

Figure 3: Location of the study transect along the tipper land of the Fall Zone in Virginia and Afaryland.

Ph.D. Thesis:

Bondar, G.H., and K.G Hirth, adviser. TracingtheTransitional: Examining Metarhyolite UseAlongtheAtlantic Seaboard During the Archaic-Woodland Transition. In progress.

87

• ,i

Biochemistry Department TIlH. USE OF IIIGII-ENERGY GAlMMA IRRADIATION TO EFFECT CRYOREDUCATION OF NI ETTALLOENZY'NI ES FOR SPECTROSCOPIC CHARACTERIZATION

Participants:

M. Bollinger, Jr., Associate Professor M. Green, Assistant Professor R.B. Guyer, Research Technician C. Krebs, Assistant Professor J.C. Price, Graduate Student L. Saleh, Graduate Student K. Stone, Graduate Student Services Provided: Gamma Irradiation Sponsor: Project 1: grant GM 69657 from NIH to CK and JMB (S 256,000/year).

Project 2: grant GM 55365 from NIH to JMB ($ 157,500 per year).

Project 3: grant GM 47295 to BHH ($190,000/year).

Project 4: grant 39647-G3 from ACS/PRF to MTG ($ 17,500/year).

Enzymes containing metal ions are wide-spread in nature and play a pivotal role in almost every aspect of life; they catalyze numerous biochemical transformations, such as key steps in the biosynthesis of DNA and antibiotics. The main purpose of our research program is to define the mechanisms on a molecular level, by which metallo-enzymes catalyze these reactions. To accomplish this goal, we employ time-resolved spectroscopic methods with the aim to identify and characterize reaction intermediates and thereby deconvoluting the catalytic mechanism.

Significant information about such species can be gained from studies of samples that have been exposed to gamma-irradiation (total dose 2 to 5 Mrad) at low-temperatures (77 K), a.k.a. 'cryoreduction'. It has been demonstrated (Davydov et al. JACS 1994, 116, 11120-11128 and references therein) that this procedure allows reduction of the metal clusters while retaining the geometry of the oxidized cluster, because the molecular motion of the radiolytically reduced metal center is impeded due to the low temperature.

This method is extremely valuable for the study of diamagnetic species, because they can be converted to paramagnetic species, which can then be interrogated in detail by paramagnetic methods, such as EPR, ENDOR, ESEEM, and Mossbauer spectroscopies. We employ this methodology to study the following projects:

I) We have recently used this method for the initial characterization of the first reaction intermediate in a mononuclear non-heme Fe-enzyme. In particular, the assignment that this species contains formally a high-spin Fe(IV) center was made possible by this technique. Additional information about the geometric and electronic structure will be obtained by the other, above-mentioned methods. Status: in progress

2) We have identified several peroxodiferric reaction intermediates in the reactions of non-heme diiron enzymes. Such species are believed to be key species in some of the non-heme diiron enzymes, and in order to gain insight into the reaction mechanisms detailed insight into the geometric and electronic structure is of high importance. We intend to employ the cryoreduction method to study the diamagnetic peroxodiferric species by the above paramagnetic methods.

Status: in progress

3) In collaboration with Boi Hanh Huynh, Emory University, we will study the enzyme ferredoxin:thioredoxin reductase, which contains an unusual iron-sulfur cluster. Again, we will attempt to convert the diamagnetic cluster to a paramagnetic cluster by cryoreduction and gain information about this species by the above methods. Status: in progress

4) We use this method to study the geometric and electroninc structure of ferryl-oxo reaction intermediates of P450 heme enzymes. These enzymes play a key role in numerous aspects of biology, and the elucidation of their structure is paramount for the understanding of their function. Status: in progress 88

Ph.D. Theses:

John C. Price, J. Martin Bollinger, Jr. (advisor), and Carsten Krebs (advisor):

Mechanistic and Structural Studies on Taurine:a-Ketoglutarate Dioxygenase Lana Saleh, and J. Martin Bollinger, Jr. (advisor):

Oxygen Activation and Electron Transfer in the R2 Subunit of Ribonucleotide Reductase from Escherichia coli Kari Stone, and Michael T. Green (advisor)

"Mechanism of Oxygen Activation by Chlioroperoxidase" Publications:

Price, J. C., Barr, E. W., Tirupati, B., Bollinger, J. M., Jr., and Krebs, C. The First Direct Characterization of a High-Valent Iron Intermediate in the Reaction of an M-Ketoglutarate-Dependent Dioxygenase: A High-Spin Fe(IV) Complex in Taurine/

-Ketoglutarate Dioxygenase (TauD) from Escherichia coli Biochemistry, 42, 7497-7508, 2003 J. M. Bollinger, Jr. Characterization of a High-Spin Fe(IV) Intermediate in the Reaction of Taurine/-Ketoglutarate Dioxygenase (TauD)

Invited talk: 11 International Conference of Biological Inorganic Chemistry. Cairns, Australia, July 2003 Price, J. C., Barr, E. W., Tirupati, B., Bollinger, J. M., Jr., and Krebs, C. On the Identity of a Novel Fe(IV) Intermediate in the Catalytic Cycle of Taurine/-Ketoglutarate Dioxygenase (TauD)

Poster presentation by J.C. Price at the II I International Conference of Biological Inorganic Chemistry, Cairns, Australia, July 2003 Price, J. C., Barr, E. W., Tirupati, B., Bollinger, J. M., Jr., and Krebs, C. Spectroscopic Characterization of a High-Spin Fe(IV) Intermediate in the Reaction of Taurine/-Ketoglutarate Dioxygenase (TauD)

Poster presentation by C. Krebs atthe I It 1 International Conferenceof Biological Inorganic Chemistry, Cairns,Australia, July 2003 Carsten Krebs Mechanism of Oxygen Activation by Taurine/-Ketoglutarate Dioxygenase (TauD)

Invited talk: 2271i Meeting of the American Chemical Society Anaheim, CA, March 2004 Michael T.Green Role of Thiolate ligation in P450 Enzymes.

Invited lecture: 3rd International Conf. on Porphyrins & Phthalocyanins(ICPP) New Orleans, July 2004 Kari Stone, Carsten Krebs, and Michael T. Green Role of Thiolate ligation in P450 Enzymes.

Poster presented by Kari Stone at the 311 International Conference on Porphyrins and Phthalocyanins (ICPP) New Orleans, July 2004 Carsten Krebs Mechanism of Oxygen Activation by Taurine/-Ketoglutarate Dioxygenase (TauD)

Invited talk: 7T European Conference on Bioinorganic Chemistry Garmisch Partenkirchen, Germany, August 2004 Price, J. C., Barr, E. W., Tirupati, B., Bollinger, J. M., Jr., and Krebs, C. On the Identity of a Novel Fe(IV) Intermediate in the Catalytic Cycle of Taurine/-Ketoglutarate Dioxygenase (TauD)

Poster presentation by J.C. Price at the 7T European Conference on Bioinorganic Chemistry Garmisch Partenkirchen, Germany, August 2004 Michael T.Greem Role of Thiolate ligation in P450 Enzymes.

Invited lecture at the 7di European Conference on Bioinorganic Chemistry Garmisch Partenkirchen, Germany, August 2004 Kari Stone, Carsten Krebs, and Michael T. Green Role of Thiolate ligation in P450 Enzymes.

Poster presentation by Kari Stone at the 7' European Conference on Bioinorganic Chemistry Garmisch Partenkirchen, Germany, August 2004 89

Civil and Environmental Engineering Department EFFECTS OF Zrn(lh1. Cti(II). Nln()l. FreAI!. NO_ or SO42 at p11 6.5 AND 8.5 ON TRANSFORNMATIONS OF HYDROUS FERRIC OXIDE (IIFO) AS EVIDENCED BY IOSSBAUER SPECTROSCOPN'

Participants:

G. Catchen, Professor B.A. Dempsey, Professor W. Burgos, Associate Professor J. Jang, Postdoctoral Research Associate/Graduate Student B. Park, Graduate Student Services Provided: Angular Correlations Lab, Laboratory Space Sponsor: Department of Energy, Natural and Accelerated Bioremediation Research Program, $764,870 The objective of the research is to determine the effects of transition metals on transformation of hydrous ferric oxide (HFO) into more thermodynamically stable ferric oxides. Ferric oxides are important environmental adsorbents. In anoxic environments, ferric oxides with Fe(ll) are important redox buffers. Transformation of HFO to more stable phases can result in decreased surface area and reduced redox potential.

In some experiments, HFO was precipitated in the presence of Cu(II), Zn(ll), Mn(ll) and/or Fe(lI). In other experiments, Fe(lI), NO,;, and/or SO42 were added to pre-formed HFO. Transmission "Fe-Mossbauer spectroscopy was used to monitor the phase changes. At pH 6.5 and 65 'C, HFO was transformed into hematite in the presence of Zn(Il) or Mn(ll).

Both metals were significantly adsorbed for these conditions, occupying about 1.2 sorption sites per nm2 of HFO surface. Transformations were not observed at pH 6.5 in the presence of Cu(Il), which was weakly adsorbed (0.06 sites per nm 2). No transformation occurred in the absence of Me(Il) transition metals. At pH 6.5 and room temperature, HFO plus Fe(Il) transformed into poorly crystalline goethite in the presence of chloride, into goethite and lepidocrocite in the presence sulfate, and into goethite and magnetite in the presence of nitrate. At pH 8.5 and room temperature, HFO that was formed with 0.033 or O.33 mM Zn(Il) and then aged with Fe(Il) was transformed into magnetite that was depleted in octahedral Fe, i.e. non-stoichiometric or possibly mixed metal spinel, (Fe3+)v(Me xFe2+, xFe3+)v'04. HFO that was aged with Cu(ll) and Fe(ll) was transformed into goethite and into magnetite that was also depleted in octahedral Fe. The transformations at pH 8.5 were completely inhibited by 3.3 mM Zn(Il) and transformations were significantly decreased by 3.3 mM Cu(Il). These results have extended observations of the transformation of HFO to neutral pH ranges and to lower concentrations of metals than previously reported.

Ph.D. Thesis:

Je-Hun Jang, "Chemistry of Environmentally Significant Phases of Oxides of Iron," Dept. of Civil and Environmental Engineering, The Pennsylvania State University, 2004.

Research Supervisor: Dr. Brian A. Dempsey Publ ications:

Jang, Je-Hun, Brian A. Dempsey, Gary L. Catchen, and William D. Burgos, "Effects ofZn(ll), Cu(Il), Mn(ll), Fe(II), NO;3

, or SO42- at pH 6.5 and 8.5 on Transformations of Hydrous Ferric Oxide (HFO) as Evidenced by Mossbauer Spectroscopy," Colloids and SurfacesA: Physicochem. Eng. Aspects, 221, 55-68 (2003).

90

Engineering Science and Mechanics Department STUDY OF TIlE CHARGE TRAPPING CHARACTERISTICS OF IlIfO/Si

Participants:

P. Lenahan, Professor A. Kang, Graduate Research Assistant Services Provided: Gamma Irradiation Sponsor: Semicondutor Research Corporation ,$250,000 Charge trapping is a major hurdle facing the integration of the high dielectric constant hafnium oxide material in complimentary metal-oxide-semiconductor devices. In collaboration with Sharp Labs of America and funded by the Semiconductor Research Corporation, we made magnetic resonance observations of the effects of flooding the dielectric material with charge carriers, i.e. through gamma irradiation. The irradiation generates several defect centers in the HfO 2 films, although the nature of these defects are still under investigation. It has been shown previously' that gamma irradiation induces charge trapping in HfO2 devices, thus, the observed centers are likely linked to the charge trapping.

1. A.Y. Kang, P.M. Lenahan, and J.F. Conley, Jr., "The Radiation Response of the High Dielectric Constant Hafnium Oxide/Silicon System." IEEE Trans Nuci. Sci. 49(6), 2636 (Dec. 2002)

Master's Thesis:

A.Y. Kang, Electron Spin Resonance observation of trapping centers in the high K hafnium oxide system. May 2004 Advisor: Patrick M. Lenahan Publications:

A.Y. Kang, P.M. Lenahan, J.F. Conley, Jr., and Y. Ono, "Physical structure of trapped electrons in atomic layer deposited hafnium oxide using Hf(NO3)4 precursor." 34th IEEE Semiconductor Interface Specialists Conference, Dec 4-6, 2003.

Washington D.C.

A.Y. Kang, P.M. Lenahan, J.F. Conley, Jr., and Y. Ono, "Reliability Concerns for HfO2/Si Devices: Dielectric Electron Traps." InternationalIntegrated Reliability Workshop, Oct. 20-23, 2003. Stanford Sierra Camp, Fallen Leaf Lake, CA.

Materials Sciences and Engineering Department ORTHOPEDIC BIONMATERIALS

Participants:

E.A. Vogler, Professor X. Liu, Ph.D. Studemt Services Provided: Gamma Irradiation Ph.D. Thesis:

Xiaomei Liu and Erwin Vogler, advisor. Influence of Growth Environment on Osteoblast Adhesion, proliferation, Morphology and Focal Adhesion Assembly Publications:

Xiaomei Liu, Jung Yul Lim, Henry J. Donahue, Erwin A. Vogler. Influence of Substratum Surface Hydrophilicity/

Hydrophobicity on Osteoblast Adhesion, Morphology, and Focal Adhesion Assembly. Biomaterials, submitted.

91

'II

COMPARTMENTALIZED BIOREACTOR FOR BONE CELL CUIXURE

Participants:

E.A. Vogler, Professor D. Ravi, Graduate Student X. Liu, Graduate Student Services Provided: Gamma Irradiation COMPARTMENTALIZED BIOREACTOR FOR LONG-TERMI CELL CULTURE An advanced bioreactor permitting extended term culture of animal cells is reported. The bioreactor is based on the principle of simultaneous-cell-growth-and-dialysis that separates a cell growth chamber from a media reservoir by a dialysis membrane, thus compartmentalizing cell growth and cell nutrition functions. As a consequence of compartmentalization, the pericellular environment is unperturbed by continuous perfusion or punctuated re-feeding schedules and "luxury macromolecules" synthesized by cells are retained in a manner that more closely simulates the in vivo condition. Extended periods of unattended cell processing can thus occur during which secretion of various bioproducts and the development of extracellular matrix can be studied.

Long-term culture in a manner that does not disturb the pericellular environment is particularly significant for bone cells, since bone formation and remodeling is a complex cell-and-protein meditated process occurring over the time frame of

• eeks to months. With the goal of developing osteoinductive biomaterials as a specific application area, phenotypic behavior of a model human osteoblast cell line (hFOB 1.19, ATCC CRL-I 1372) and mouse calvaria derived osteoblast cell line (MC3T3, ATCC CRL.2593) cultured in the bioreactor was compared to that observed under conventional culture conditions. Attachment and growth of hFOB and MC3T3 cultured in the bioreactor was evaluated using optical microscopy, scanning and transmission electron microscopy (SEM/TEM). Differentiation was evaluated using Alkaline Phosphatase activity (ALP) staining and Von Kossa assay. hFOB cultured in the reactor for 15 days without sub-culturing formed up to 4 cell layers and stained for ALP activity. In sharp contrast, cells cultured for an equivalent period in conventional tissue culture flasks, also without subculture but re-fed every 2 days, exhibited continuous cell shedding, ruffled edges, and failed to form either multilayers or exhibit ALP activity. MC3T3 cultured in the bioreactor for 30 days, formed a tightly packed, dense layer of cells revealing uniform and extensive mineralization with Von Kossa assay. Results suggest that stable culture conditions afforded by the reactor has enhanced utility in the long-term culture of osteoblasts in terms of cell growth, proliferation and mineralized matrix deposition characteristics. The compartmentalized bioreactor thus shows promise as a tool for long-term culture conditions, and specifically for evaluation of bone-cell interactions with orthopedic biomaterials.

Ph.D. Thesis:

Thesis

Title:

Compartmentalized Bioreactor for long-term cell culture Graduate Student: Dhurjati Ravi.

Advisor: Prof. Ervin A. Vogler.

Publications:

Ravi, D, Vogler E.A., Compartmentalized Bioreactor for Long-term Cell Culture, 7 th Annual New Jersey Symposium on Biomaterials, New Brunswick, NJ.

Ravi, D, Vogler E.A., Compartmentalized Bioreactor for Long-term Cell Culture, Biointerface, Annual Meeting of the Surfaces in Biomaterials Foundation, Baltimore, MD.

92

Plant Pathology Department. Fusarium Research Center

Participants:

J.Juba, Research Support Technologist Services Provided: Gamma Irradiation Carnation leaves are irradiated in the Cobalt-60 facility in order to provide a sterile growing medium for Fusarium species at the Fusarium Research facility. Nearly every project in our lab relies on the use of these leaves and as far as I know we are the only source of irradiated carnation leaves worldwide. We make them available to others in the Fusarium research community, charging fees to cover our costs. You might find some helpful information at http://

frc.cas.psu.edu/.

Publications:

I. Garz6n, C.D., Geiser, D.M., and Moorman, G.W. Accepted with revision.Analysis ofAFLP and ITS sequence variation reveals a cryptic species boundary within Pythium irregulare. Phytopathology.

2. O'Donnell, K., Sutton, D.A., Rinaldi, M.G, Magnon, K.C., Cox, P.A., Revankar, S.G., Sanche, S., Geiser, D.M., Juba, J.H., van Burik, J.H., Padhye, A. and Robinson, J.S. In Press. Genetic Diversity of Human Pathogenic Members of the Fusarium oxysponum Complex Inferred from Gene Genealogies and AFLP Analyses: Evidence for the Recent Dispersion of a Geographically Widespread Clonal Lineage and Nosocomial Origin. J. Clin. AMicrobiol.

3. Garz6n, C.D., Geiser, D.M., and Moorman, GAY. In Press. Diagnosis and population analysis of Pythium species using AFLP fingerprinting. Plant Disease.

4. Geiser, D.M., Lewis Ivey, M.L., Hakiza, G., Juba, J.H. and Miller, S.A. In Press. Gibberellaxylarioides (anamorph:

Fusariun,xylarioides), a causative agent of coffee wilt disease in Africa, is a previously unrecognized member of the G fiijikuroi species complex. Afycologia.

5. Geiser, D.M., Jimdnez-Gasco, M., Kang, S., Makalowska, I., Veerarahavan, N., Ward, T.J. Zhang, N., Kuldau, GA.,

and O'Donnell, K. 2004. FUSARIUM-ID v.1.0: A DNA sequence database for identifying Fusarium. European Journalof Plant Pathology 110: 473-479.

6. O'Donnell, K., Ward, T.J., Geiser, D.M., Kistler, H.C., and Aoki, T. 2004. Genealogical concordance between the mating type locus and seven other nuclear genes supports formal recognition of nine phylogenetically distinct species within the Fusarium gramineanum clade. Fungal Genetics and Biology 41:600-623.

7. Taylor, J.W., Blackwell, M., Geiser, D.M., Hibbett, D.S., James, T.Y., Lutzoni, F., O'Donnell, K.L., Porter, D., Spatafora, JAY., and Spiegel, F. 2004. The History of Fungi. In: Assembling the Tree of Life, Cracraft, J. and Donoghue, M.J.,

eds., Oxford University Press.

8. Geiser, D.M. 2004. Practical fungal molecular taxonomy: In: Advances in Fungal Biotechnology for Industry.

Medicine and Agriculture. Tkacz, J. and Lange, L., eds. Kluwer Academic Publishers.

9. Geml, J. Geiser, D.M., and Royse, D.J. 2004. Phylogenetic relationships of the genus Agaricus . Mfycological Progress 3: 157-176.

10. Jurjevic, Z., Wilson, D.M., Wilson, J.P., Geiser, D.M., Juba, J.H., Mubatenhema, W., Rains, G.C. and Widstrom, N.

In Press. Fusarium species and fumonisin production on pearl millet and corn from Georgia, USA. Myfcopathologia.

Seifert KA, Aoki T, Baayen RP, Brayford D, Burgess LW, Chulze S, Gams W, Geiser, D.M., de Gruyter J, Leslie JF, Logrieco A, Marasas WFO, Nirenberg Hi, O'Donnell K, Rheeder J, Samuels GJ, Summerell BA, 93

Northeast Technology Corporation TESTING OF BORAL UNDER CONDITIONS SIMULATING VETTING AND V'ACUUNI DRYING IN SPENT NUCLEAR FUEL STORAGE CASKS

Participants:

K. Lindquist, Ph.D.

D. Vonada Services Provided: Laboratory Space Sponsor: Electric Power Research Institute, AAR Cargo Systems, Inc., ENRESA BORAL has been observed to develop large blisters in the aluminum cladding during vacuum drying. Equipment was constructed (Figure 1) to simulate the period when fuel is loaded and the multiple purpose canister (MPC) is in the pool and the BORAL is exposed to the pool water. Following exposure to the pool water the samples of BORAL are placed in a vacuum oven (Figure 2) and slowly brought to 5501F at a controlled rate. This simulates draining of the MPC and vacuum drying.

These studies evaluated BORAL processing variables, MPC drying conditions and as-fabricated BORAL attributes, which have an influence on the propensity for blister formation. The results of the work are providing the manufacturer of BORAL (AAR Cargo Systems, Inc.) with the basis for modifying process variables to provide a blister resistant material.

Figure 1: Aluminum Pressure Vessels and Temperature Controller 94

Figure 2: Vacuum Oven Publications:

EPRI Report 1008441" BORAL Behavior under Simulated Cask Vacuum Drying Conditions", September 2003.

PHYSICAL CIIAR.%CTERIZtrTION OF NEUTRON ABSORBER MATERIALS

Participants:

K. Lindquist, Ph.D.

D. Vonada S. Leuenroth Services Provided: Neutron Irradiation, Laboratory Space Surveillance coupons from spent fuel pools at nuclear stations are tested and characterized with respect to their physical attributes. Materials tested include BORAL, Boraflex and borated stainless steel. A key attribute tested is the neutron absorption characteristics. This test is performed in the Neutron Beam Laboratory.

95

'I,

SECTION B. OTHER UNIVERSITIES, ORGANIZATIONS &

COMPANIES UTILIZING THE FACILITIES OF THE RSEC

. 1OM A ttjt 4-  ;  ;  ;.

ADP Life Sciences Gamma Irradiation Clarion University Neutron Activation Analysis COGEMA Neutron Radiography Neutron Radioscopy Neutron Transmission Cornell University Neutron Radioscopy David Martin Gamma Irradiation Eagle-Picher Neutron Radiography Neutron Radioscopy Neutron Transmission Exelon Neutron Transmission Fairchild Corporation, Mountaintop Semiconductor Irradiation Fairchild Corporation, South Korea Semiconductor Irradiation General Motors Neutron Radiography Neutron Radioscopy Lockheed Martin Semiconductor Irradiation NETCO (Northeast Technology Corporation) Neutron Radioscopy Neutron Transmission Northrup-Grumman (formerly TRW) Irradiation of Electronic Devices Novax, Inc. Neutron Irradiation NWT Isotope Production Physical Acoustics Neutron Irradiation Gamma Irradiation Primasep Gamma Irradiation Raytheon Company, Sudbury, MA Irradiation of Electronic Devices Raytheon Systems Company, El Sequndo, CA Irradiation of Electronic Devices Raytheon, St. Petersburg, FL Irradiation of Electronic Devices Richard Gazzini Gamma Irradiation SAIC Neutron Irradiation Suntronics Neutron Irradiation Syngenta Crop Production Gamma Irradiation Toyota Neutron Radioscopy TRACERCO (formerly Synetix, Inc.) Isotope Production Tru-Tec Isotope Production University of Pittsburgh, Greensburg Neutron Activation Analysis Westinghouse Science & Technology Center Neutron Irradiation 96

PUBLICATIONS I..

_I ' N I Ad--" goi p- p._. Je.

I~,%l ilf

PUBLICATIONS PUBLICATIONS Mechanical and Nuclear Engineering Department B. Sarikaya, F.Alim, K. Ivanov, K. DnIl, J. Brenizer, Y. Azmy, "Alodelling of ExistingBeamport Facility at PSU Breazeale Reactor by using MCNF', Proceedings of PHYSOR 2004 -The Physics of Fuel Cycles and Advanced Nuclear Systems: Global Developments Chicago, Illinois, April 25-29, (2004)

C. Tippayakul, K. N. Ivanov, C. F. Sears, G.M. Morlang and B. J. Heidrich, "Automated Three-dimensional Depletion Capability for the Pennsylvania State University Research Reactor", Proceedings of PHYSOR2004, April 25-29, 2004, Chicago, IL, USA.

D.K. Hauck, K. Onlil, P.1. Kuniholm, J.J. Chiment, "Uses of NAA: Gold Concentrationsin Dated Tree Rings, " Trans.

Am. Nucl. Soc., 9Q, 320 (2004).

J. Brenizer, C. F. Sears, K. Onili, L. H. Tsoukalas, T. Jevremovic, J. Stubbins, R. Agasie, M. Corradini, "An Update of the Consortium of Big-10 University Research and Training Reactors INIE Activities", Trans. Am. Nucl.

Soc., 88, 649 (2003).

J. Brenizer, C. F. Sears, K. Onla, L. H. Tsoukalas, T. Jevremovic, J. Stubbins, R. Agasie, M. Corradini, " A Review of Year One INIE Activities of the Consortium of BIG-10 URTRs", Trans. Am. Nucl. Soc., 89, 858 (2003).

J. Niederhaus, J. Brenizer, K. Unlt, "Development of a Single-Disk Neutron Chopperfor 7ime-of Flight Spectrometry at Penn State", Trans. Am. Nucl. Soc., 89, 677 (2003).

J. Niederhaus, J. Brenizer, K. Unlti, "Thermal Neutron Time-of-Flight Spectroscopy at Penn State using a Single-Disk Chopper", Proceedings of PHYSOR 2004 -The Physics of Fuel Cycles and Advanced Nuclear Systems: Global Developments Chicago, Illinois, April 25-29, (2004)

K. Unla, J. Brenizer, C. F. Sears, "Nuclear EngineeringResearch and Education Enhancements at Penn State",

Trans. Am. Nucl. Soc., 88, 647 (2003).

K. OnIla, P. 1.Kuniholm, J. J. Chiment, D. K. Hauck, "Neutron Activation Analysis of Absolutely-Dated Tree Rings",

Accepted for publication in Journal of Radioanalytical and Nuclear Chemistry (2003)

M. Deinert, C. W.Lowe, J.-Yev. Parlange, K. Onlil, K. B. Cady, "Performance and Calibration of a Neutron Image Intensifier Tube Based Real-time Radiography System", Submitted for publication in IEEE Transactions on Nuclear Science, (2003)

N. Kriangchaiporn, K. Ivanov, A. Haghighat, and C. Sears. (2004). Multi-Group Cross-Section Generation for TRIGA Core Analysis. TANSAO.

N. Kriangchaipom, K. Ivanov, C. Sears, G.Morlang, and B. Heidrich. (2001). Advanced Fuel Management Code System for the Pennsylvania State University Breazeale Reactor (PSBR). TANSAO. 85:415-417.

N. Pekula, K. Heller, P.A. Chuang, A. Turhan, M.M. Mench, J. S. Brenizer, K. WnUt, " Study of Water Distribution and Transport in a Polymer Electrolyte Fuel Cell Using Neutron Imaging," Nuclear Instrumentation Methods, Section A. (Accepted for publication)

N. Pekula, M. M. Mench, K. Heller, K. onla, J. Brenizer, "Neutron Imaging of Two-phase Transport in a Polymer Electrolyte Fuel Cell," Trans. Am. Nucl. Soc., 2Q. 309 (2004).

S. M. Cetiner, K. Onlt, G. Downing, "Development of time-of-flight neutron depth profiling at the Pennsylvania State University:" Trans. Am. Nucl. Soc., 9Q, 311 (2004).

Z. Huang, and R.M. Edwards. Hybrid Reactor Simulation of BWR Power Oscillations. Aluclear Technology. 143:132-143 (2003).

97

Plant Pathology Department C.D. Garz6n, Geiser, D.M., and Moorman, G.W. Accepted ivith revision. Analysis of AFLP and ITS sequence variation reveals a cryptic species boundary within Pythtiutn irregulare. Phytopathology.

K. O'Donnell, Sutton, D.A., Rinaldi, M.G., Magnon, K.C., Cox, P.A., Revankar, S.G., Sanche, S., Geiser, D.M., Juba, J.H.,

van Burik, J.H., Padhye, A. and Robinson, J.S. In Press. Genetic Diversity of Human Pathogenic Members of the Fusarium oxysporrnt Complex Inferred from Gene Genealogies and AFLP Analyses: Evidence for the Recent Dispersion of a Geographically Widespread Clonal Lineage and Nosocomial Origin. J. Clin. ificrobiol.

C.D.Garz6n, Geiser, D.M., and Moorman, G.W. ln Press. Diagnosis and population analysis of Pythium species using AFLP fingerprinting. Plant Disease.

D.M. Geiser, Lewis Ivey, M.L., Hakiza, G., Juba, J.H. and Miller, S.A. In Press. Gibberella xylarioides (anamorph:

Fusariunixylarioides), a causative agent of coffee wilt disease in Africa, is a previously unrecognized member of the G fiijikutroi species complex. Ilycologia.

D.M. Geiser, Jimdnez-Gasco, M., Kang, S., Makalowska, I., Veerarahavan, N., Ward, T.J. Zhang, N., Kuldau, GA., and O'Donnell, K. 2004. FUSARIUM-ID v.1.0: A DNA sequence database for identifying Fusariunt. European Journal of Plant Pathology 110: 473-479.

K. O'Donnell, Ward, T.J., Geiser, D.M., Kistler, H.C., andAoki, T. 2004. Genealogical concordance between the mating type locus and seven other nuclear genes supports formal recognition of nine phylogenetically distinct species within the Fusariunt graninearuni clade. Fungal Genetics and Biology 41:600-623.

J.W. Taylor, Blackwell, M., Geiser, D.M., Hibbett, D.S., James, T.Y., Lutzoni, F., O'Donnell, K.L., Porter, D., Spatafora, J.W., and Spiegel, F. 2004. The History of Fungi. In: Assembling the Tree of Life, Cracraft, J. and Donoghue, M.J., eds., Oxford University Press.

D.M. Geiser, 2004. Practical fungal molecular taxonomy: In: Advances in Fungal Biotechnology for IndustrM. Medicine and Agriculture. Tkacz, J. and Lange, L., eds. KluwerAcademic Publishers.

J. Geml, Geiser, D.M., and Royse, D.J. 2004. Phylogenetic relationships of the genus Agaricus . Mycological Progress 3: 157-176.

Z. Jurjevic, Wilson, D.M., Wilson, J.P., Geiser, D.M., Juba, J.H., Mubatenhema, W., Rains, G.C. and Widstrom, N. In Press. Fusarium species and fumonisin production on pearl millet and corn from Georgia, USA.

MIlycopathologia.

K.A. Seifert, Aoki T, Baayen RP, Brayford D, Burgess LW, Chulze S, Gams W, Geiser, D.M. , de Gruyter J, Leslie JF, Logrieco A, Marasas WFO, Nirenberg HI, O'Donnell K, Rheeder J, Samuels GJ, Summerell BA, Northeast Technology Corporation EPRI Report 1008441" BORAL Behavior under Simulated Cask Vacuum Drying Conditions", September 2003.

Biochemistry Department J.C. Price, Barr, E. W., Tirupati, B., Bollinger, J. M., Jr., and Krebs, C. The First Direct Characterization of a High-Valent Iron Intermediate in the Reaction of an cC-Ketoglutarate-Dependent Dioxygenase: A High-Spin Fe(lV) Complex in Taurine/-Ketoglutarate Dioxygenase (TauD) from Escherichia coli Biochemistry, 42, 7497-7508, 2003 98

Civil and Environmental Eneineering Department J. Jang, Brian A. Dempsey, Gary L. Catchen, and William D. Burgos, "Effects of Zn(Il), Cu(II), Mn(ll), Fe(lI), NO;3, or SO42 at pH 6.5 and 8.5 on Transformations of Hydrous Ferric Oxide (HFO) as Evidenced by Mossbauer Spectroscopy," Colloids and SurfacesA: Physicochem. Eng. Aspects, 221, 55-68 (2003).

Engineering Science and Mechanics Department A.Y. Kang, P.M. Lenahan, J.F. Conley, Jr., and Y.Ono, "Physical structure of trapped electrons in atomic layer deposited hafnium oxide using Hf(N03)4 precursor." 34th IEEE Semiconductor Interface Specialists Conference, Dec 4-6, 2003. Washington D.C.

A.Y. Kang, P.M. Lenahan, J.F. Conley, Jr., and Y.Ono, "Reliability Concerns for HfO2/Si Devices: Dielectric Electron Traps." InternationalIntegrated Reliability Workshop, Oct. 20-23, 2003. Stanford Sierra Camp, Fallen Leaf Lake, CA.

D. Ravi, Vogler E.A., "Compartmentalized Bioreactor for Long-term Cell Culture." 7 th Annual New Jersey Symposium on Biomaterials, New Brunswick, NJ.

D. Ravi, Vogler E.A. "Compartmentalized Bioreactor for Long-term Cell Culture." Biointerface. Annual Afeeting of the Surfaces in Biomaterials Foundation, Baltimore, MD.

Ph.D. THESES Biochemistry Department J. C. Price, J. Martin Bollinger, Jr. (advisor), and Carsten Krebs (advisor). Mechanistic and Structural Studies on Taurine:?-Ketoglutarate Dioxygenase L. Saleh, and J. Martin Bollinger, Jr. (advisor). Oxygen Activation and Electron Transfer in the R2 Subunit of Ribonucleotide Reductase from Escherichia coli K. Stone, and Michael T. Green (advisor). "Mechanism of Oxygen Activation by Chloroperoxidase" Civil and Environmental Engineering Department J. Jang, "Chemistry of environmentally significant phases of oxides of iron," Dept. of Civil and Environmental Engineering, The Pennsylvania State University, 2004.

Research Supervisor: Dr. Brian A. Dempsey Engineering Science and Mechanics Department X. Liu, Erwin Vogler, advisor. Influence of Growth Environment on Osteoblast Adhesion, proliferation, Morphology and Focal Adhesion Assembly D. Ravi, E.A. Vogler. "Compartmentalized Bioreactor for long-term cell culture."

MASTER'S THESES Mechanical and Nuclear Engineering Department C. Tyree. "Neutron IrradiatedSilicon Carbide Studied Using Positron Annihilation Lifetime Spectroscopy" Advisors: G.Catchen, A. Motta. (2004).

99

N. Pekula, "Visualization and Measurement of Water Accumulation and Transport in an Operating PEFC Using Neutron Imaging", M. S. Thesis, Spring 2004.

N. Kriangchaiporn, K. Ivanov, advisor. Advanced Fuel Management System (AFMS) for PSBR, 2001.

N. Kriangchaiporn, K. IvanovA. Haghighat, C.F. Sears (2003). "Parallel Transport Model based on 3-D Cross-Section Generation for TRIGA Core Analysis."

Engineering Science and Mechanics Department A.Y. Kang, Electron Spin Resonance observation of trapping centers in the high ? hafnium oxide system. May 2004.

Advisor: Patrick M. Lenahan X. Liu, Jung Yul Lim, Henry J. Donahue, Erwin A. Vogler. Influence of Substratum Surface Hydrophilicity/

Hydrophobicity on Osteoblast Adhesion, Morphology, and Focal Adhesion Assembly. Biomaterials, submitted.

100

APPENDICES 4 -

J 4.

.a.. A

APPENDIXA Personnel Utilizing the Facilities of the Penn State RSEC.

Faculty (F), Staff (S), Graduate Student (G), Undergraduate (U), Visiting Professor (VP), Visiting Scholar (VS), Faculty Emeritus (FE), Post-Doctoral (PD), High School Student (HS)

• 0 I Straka. William IF Chaung, Abel G Welz, Joseph F Cimbala, John F Connelly, Saray U Daubenspeck, Thierry S Davison, Candace S Juba,Jean S Decker, Chanda U Edwards, Bob F Flinchbaugh, Terry S Hauck, Danielle G Heidrich, Brenden F Heller, A. Kevin G Phelps, Mwita G Hochreiter, Larry F Naraayananm, Beepa G Hoover, Jared U Ivanov, Kostadin F

'II *sLRUMS Kinney, Brian U Koziol, Adam U Burgos, William F Kriangchaiporn, Natekool G Dempsey, Brian F LoVerde, Bianca U Jang, Je-Hun PD Marcy, Melisa U Park, Byungtae G McCullough, Randy S Mench, Matt F Alim, Fatih G Miller, Doug U Degalahal, Vijay G Morlang, G. Michael G Irwin, Mary Jane F Motta, Arthur F Narayanan, V. F Palacios, Fernando U Xie, Yuan F Pekula, Nick G Portanova, Alison S Hawk, Gavin G Pye, Brian U Kang, Andrew G Rankin, Paul S Lenahan, P. F Rickert, Bret U Sears, C. Frederick F Adamonis, Jaclyn U Shields, Dan G Azmy, Yousry F Skilone, Dan U Bachman, Ben U Slaybaugh, Rachel U Bernecker, Aaron U Soung, Stephen U Brenizer, Jack F Talley, Ashley U Bryan, Mac S Tippayakul, Chanatip G Catchen, Gary F Tobin, Dan G Cetiner, Sacit G Todorova, Nadejda G Chang,Jong G Tracey, Michael U 101

" ci ci @i DUSJ Dkh'A I (@Jh1k I DhMWa Trivelpiece, Cory G Turhan, Ahmet G Bertocchi, Dave S Tyree, Chris G Boeldt, Eric S OniO, Kenan F Hermann, Greg S Vijaykrishnan, N. G Linsley, Mark S Vincenti, John S Morlang, Suzanne S Wilmot, Aaron U Wiggins, Jim S Yilmaz, Serkan G Zerr, Robert U Bondar, Greg _ _G Fleming, J. U Hirth, K. F Bollinger, M.J., Jr. F Guyer, R.B. S Krebs, Carsten F Price, J.C. G Saleh, L. G Stone, K. G Ma, Hong F Li, Wuxing G Allcock, Harry F Chalkova, Elena S Gerlach, Denise U Phelps, Mwita G Liu, Xiaomei Ravi, Dhurjati G Vogler, Erwin F PI UMI . .

Barzilov, Alexander Sokol, Paul F 102 U

ADP Life Services Roy Hammerstedt Clarion University Frank Vento COGEMA Gilles Bonnet Jean-Franciose Giraldi Jean Oudut Laurent Stachetti Cornell University Mark Dinert David Martin David Martin Eagle-Picher Monte Hart Jerry Houdyshell Sandi Rushin Exelon Nelson Heddle Milton M ui Fairchild Corporation, Mountaintop Joe Macieunas Fairchild Corporation, South Korea Jiwall Joung General Motors Eric Thompson Tom Trabold Lee Whitehead Lockheed Martin Alex Bogorad Larry Bruccoliere Steve Mover NETCO (Northeast Technology Corporation) S. Levenroth Ken Lindquist Doug Vonada Northrup-Grumman (formerly TRW) Frank Cornell Don Randall Novax, Inc. John Knell NWT Jerre Palino Physical Acoustics Weiming Dai Jim Esposito Primasep Charles Coleman Raytheon Company, Sudbury, MA Bruce Black Jacques Casteel Raytheon Systems Company, El Sequndo, CA Ed Craig Raytheon, St. Petersburg, FL Craig Uber Richard Gazzini Richard Gazzini SAIC Ed Draper Suntronics David Ripley Syngenta Crop Protection Leslie Berger Toyota Kiyoshi Byokota Katsuhiko Kinoshita Kazuki Kuwabara Seiichi Matsumoto Chao-Yang Wang Yasuhiro Yamamoto TRACERCO Mike Boone Tru-Tec Mike Flinniken Eric Growney University of Pittsburgh, Greensburg Hollie Ramaley Tim Savisky Ted Zaleskiewicz Westinghouse Science and Technology Center Abdul Dulloo Frank Ruddy 103

APPENDIXB FornialTour Groups MNE--~~ - ---- -- = ~ 07/02/03- ~~~-1= Chemistry Department 08/07/03 2 PowerPla 07/02/03 33 Police Services 08/08/03 1 VIEW 07/03/03 22 Police Services 08/08/03 1 Scalacs; 07/07/03 1 Animal.Resources 08/13/03 1 fPGSAS  ; 07/07/07/03 26 , General Motors 08/13/03 1 Personal ,.7/0/ 3.: 1, Personal 08/15/03 1 PGSAS 07/08/03 42 Personal 08/15/03 3 TRAC 07/08/03 5 "II-VI Products, 08/18/03 ,17,

,MR-- ' ' '07/09/03--- -2 Grier School 08/19/03 1 L~SurchatqvInstitute 07~/09/03 -1 Personal 08/19/03 1 Personal 07/14/03 1 Manufacturing Sciences 08/20/03 - 1 Teacher Workshop _ 07/14/03 14 LUniversity Police ._ . . 08/25/03 Teacher Workshop 07/15/03 14 College of Engineering 08/27/03 1

,Teacher Workshop-, . 07/16/03, . Personal 08/29/03 1 Slice of Science 07/17/03 10 Visiting Student . -- , 09/08103 1' TRS Technologies 07/17/03 3 P.ADE - a 09/08/03Q. 1 PSNES Representative . 07/17/03 1 Pathfinder Fuel Group 09/09/03 8

,Westinghoys 07/18/03 2 Central VA Governor's School 09/12/03 18 Spend a Summer Day 07/21/03 6 Parents Weekend Open House 09/13/03 196 Spend a Summer Day 07/21/03 6 ANucE 401 09/22/03- .6-.

Soil and Crop Department 07/22/03 1 Former Director 09/22/03 1 LEhysics Department . .07/23/,03 1 Engineering Seminar 09/22/03 13 Student 07/23/03 1 College of Engineering 09/23/03 1 Medical.Physics 07/23/03 1 :Houserville-Elementary 09/25/03 , 01

, PrsnaA--a---

-- -a -- a---a------~07/24/03--.-2 Former Student 09/26/03 1 Spend.aSummerDay 07/25/03 Computer Science & Engineering 09/30/03 2 Spend a Summer Day 07/28/03 7 NucE 301 10/01/03 28 Sear-Brown 07/29/03 1 CNSC 10/02/03 -2 BMB - 07/29/03 1 Geology 10/06/03 1

.Sear:Brown _.07/30/03_ 1 NucE 401 10/14/03 7 Prospective Student 07/31/03 3 Health Physics 10/14/03 7 i Spend a Summer Day 08/01/03 2 _RPQ ut 77- 10

,BMB -08/04/03 1 PPL 10/20/03 1 Warner Review - 08/06/03. . 2 DOE 10/22/03 6

APPENDIXB Formld Tour Groups E7.1". 3. Ce-.- .I LI.-7010E Primasep 10/23/03 1 NucE 401. 12/09/03 6 Los Alamos National Lab 10/27/03 1 ECS - 12/10/03 22. .

IPersonal 10/27/03 1 University Police 12/11/03 1

!Personal:, _. ,__ 10/31/03 2 Grier School 12/12/03 1 PSRSC Audit 11/03/03 1 'Police Services 12/18/03 .1 Bettis 11/04/03 1 ,PoliceTraining ,, , , ,_ ___ 12/22/03 1

_18 Mistler 11/04/03 2 NRC 01/08/04 2 LWISE_ _11/05/03. 1 M&NucE 01/09/04 1 ME Professor 11/05/03 1 Police Training 01/09/04 20 NRC 11/05/03 1 BMB _ , 01/12/0,4 22

[Ligonier Valley 11/06/03 39 Freshman Seminar 01/13/04 9

,Virginia Tech ,, , 11/07/03 1 Toyota 01/13/04 5 Prospective Student 11/08/03 21 University Pitt Greensburg 01/14/04 2 ME Professor 11/10/03 1 Personal _ , 01/14/04 1_

FoodScience . ,1.1/13/03 13 j Student 01/15/04 1 iFormer Student__. ___ 11/14/03 _1 WISER 01/15/04 2 0 Prospective Student 11/17/03 2 ,BMB . 01/16/04 4, ME 33 11/18/03 5 INucE 450 .01/20/04 15 ._

TME 33 i lv,= Mo 11'1A/3 i 2 Personal 01/20/04 1

[ME 33. - --

I- . -.. . -- ,

,, ,,, ,,,,,1,1/20/03 ,, A. U

, 6 - . ,j Physics Department 01/21/04 1 ME 33 11/20/03 5 NucE 450 01/22/04 13 Biology 11/21/03 1 Ilnterns 01/22104 2 _-

Prospective Student 11/25/03 2. Dean's Office 01/27/04 1 iPennTech College., 11/25/03 23 , M&NucE 01/27/04 1 Former Employee 11/26/03 1 WME Student, 01/27/04 1 I Framatome ANP 11/26/03 1 M&NucE _ 1/29/04 2 j ME 33 12/02/03 5 Personal 01/31/04 3

[ME 33 _ 12/02/03 2 M&NucE 02/02/04 1 EASI House 12/02/03 17 ~Computer Science & Engineering 02/02/04 3 IE 408W 12/03/03 21 Student__ , 02/04/04 - -

.ME 33 . 12/04/03 3 Seminar Speaker 02/05/04 3 IE 408W _ , , 12/04/03 22,, Student 02/06/04 1 IE 408W 12/05/03 20 ,Dean's Office 02/10/04 2 i NucE 31OW 12/08/03 2 i M&NucE 02/10/04 1 4'

APPENDIXB Formal Tour Groups

.,Greg Do-wningri= -- 02/13/04 'I- ECS 04/06/04 1 Personal_ 02/16/

0 4 3 Student 04/07/04 1 Jr Science Museum 02/19/04 20 Bettis and Naval Research 04Q08/04 5 Brockway High School 02/20/04 15 Cornell University. ,04/08/04- 1

.Blue Chip Recruits 02/21/04 3 Prospective Student 04/08/04 6 Personal. . 02/24/04 1 Greensburg-Salem High School 04/13/04 14 STS Interest House 02/24/04 4 Student 04/13/04 .1 NRC Exit Interview 02/27/04 1 Student , 3/04 ...

Lock Haven- -- - - 02/28/04- 9 Berwick High School 04/14/04 9 Engineeringpen House._,02/28/04 14- Computer Science & Engineering 04/15/04 1 Open House 02/28/04 14 Student 04/16/04 2 J Engineering Open House 02/28/04 46 Personal 04/16/04 . 1_

Engineering Open House 02/28/04 25 Student 04/16/04 1 LEngineeringOpen House 02/28/04 9_ OEA 04/19/04 1 Bald Eagle High School 03/02/04 14 Physics Department - 04/20/04 1 PSU Ambulance 03/02/04 8 .Wyomissing, . . 04/21/04 _ .4 0

CD Fuel Cell Group 03/18/04 1 Take Your Daughters & Sons to Work 04/22/04 16 Seminar Speaker .03/18/0.4 _ 1 Take Your Daughters & Sons to Work 04/22/04 16 Spring Grove High School 03/19/04 1 Take Your Daughters & Sons to Work 04/22/04 13 Girl Scouts 03/20/04 26 RyaNyy ___.04!.

Cornell University 03/22/04 1 Centre County Sheriff 04/23/04 2 LP.AJSHS 03/22/04 '6 Personal 04/26/04 1 Student 03/23/04 1 Camp Hill High School 04/26/04 13 Altoona Chemistry 03/23/04 8 Wlliamson-High School 04/27/04 26 i Seminar Speakers -03/25/04,-. ' Punxsutawney High School 04/28/04 8 Personal 03/25/04 . 1 Personal 04/29/04 1 Prospective Student 03/29/04 2 Bedford High School 04/30/04 26 Student 03/29/04 1 ME3OH._ -. 04/30/04 -4 Tyrone Middle School 03/30/04 41 Moshannon Valley Jr/Sr High School 05/06/04 36 Jyrone Middle School ._. _ 03/30104. 10 Personal 05/10104 2 EMS 04/01/04 1 Geography -. 05/11/04 1 Lycoming College _04/01/04 ...... 10 LEngineering Services- - 05/12,/04. _- 1 Personal 04/01/04 1 Bald Eagle High School 05/15/04 1 0 .... .....44 [ST and Bechtel 05/17/04 5

APPENDIXB Formal Tour Groups Kane High School 05/17/04 27 Mifflin Co. Christian 05/18/04 17 ECS 05/18/04 1 PJAS _ 05/18/04 3 Spring Grove High School 05/19/04 16 Personal 05/19/04 2 I1B Davison Middle School 05/20/04 17

,Bettinenn HS Science Olympaid 05/20/04 27 Personal 05/21/04 4 Personal 05/25/04 2 FUnlu Meeting 05/27/04 1 Personal - 06/07/04 2 Prospective Student 06/11/04 3 Personal 06/15/04 1 jKARI06/21/04 3 IHighSchool!Teacher 06/22/04 1 0 Research Undergraduate Experience 06/23/04 22 Student 06/23/04 1

'VIEW Group 06/24/04 28 PSU Grad Student 06/28104 1 EMS 06/28/04 1 WISE Group A 06/30/04 16 MWISE Group B 06/30/04 16 I

TO L . .. --. ... .I . _ . - . . 1 6. 9 TOTAL 1697

• 186 other individuals visited the facility but did not partake in a formal tour (i.e., caterers, physical plant supervisors, human resource reps, office maintenance personnel, vendors, etc.)