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Neutron Coincidence Counting Studies

Description: The efficiency comparison for measured and simulated responses of a 10B-lined proportional counter and a 3He proportional counter in a close, symmetrical geometry are presented. The measurement geometry was modeled in MCNPX to validate the methods used for simulating the response of both the 3He and 10B-lined tubes. The MCNPX models agree within 1% with the 3He tube measurements and within 3% for the 10B-lined tubes when a 0.75-┬Ám boron-metal lining is used.
Date: August 31, 2012
Creator: Rogers, Jeremy L.; Ely, James H.; Kouzes, Richard T.; Lintereur, Azaree T. & Siciliano, Edward R.
Partner: UNT Libraries Government Documents Department

Uranium Neutron Coincidence Collar Model Utilizing Boron-10 Lined Tubes

Description: The Department of Energy Office of Nuclear Safeguards and Security (NA-241) is supporting the project Coincidence Counting With Boron-Based Alternative Neutron Detection Technology at Pacific Northwest National Laboratory (PNNL) for the development of a 3He proportional counter alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a system based upon 10B-lined proportional tubes in a configuration typical for 3He-based coincidence counter applications. This report, providing results for model development of Alternative Boron-Based Uranium Neutron Coincidence Collar (ABUNCL) designs, is a deliverable under Task 2 of the project.
Date: September 18, 2012
Creator: Rogers, Jeremy L.; Ely, James H.; Kouzes, Richard T.; Lintereur, Azaree T. & Siciliano, Edward R.
Partner: UNT Libraries Government Documents Department

Boron-10 Lined Proportional Counter Wall Effects

Description: The Department of Energy Office of Nuclear Safeguards (NA-241) is supporting the project 'Coincidence Counting With Boron-Based Alternative Neutron Detection Technology' at Pacific Northwest National Laboratory (PNNL) for development of an alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a boron-lined proportional tube based system in the configuration of a coincidence counter. This report provides information about how variations in proportional counter radius and gas pressure in a typical coincident counter design might affect the observed signal from boron-lined tubes. A discussion comparing tubes to parallel plate counters is also included.
Date: May 1, 2012
Creator: Siciliano, Edward R. & Kouzes, Richard T.
Partner: UNT Libraries Government Documents Department

INVESTIGATION OF THE (10B,6Li* (3+, 2.18 MeV)) REACTION AS A METHOD FOR alpha-CLUSTER TRANSFER STUDIES

Description: The four-nucleon transfer reaction {sup 12}C({sup 10}B, {sup 6}Li*(2.18 MeV)) {sup 16}O has been studied at 68 MeV by coincidence measurement of the d + {alpha} breakup particles. The reaction is quite selective as is observed in other established {alpha}-transfer reactions.
Date: July 1, 1980
Creator: Bice, A.N.; Shotter, A.C.; Stahel, D.P. & Cerny, J.
Partner: UNT Libraries Government Documents Department

BURNOUT DISTRIBUTION IN SM-1 (APPR-1) CONTROL ROD ELEMENTS, FIXED ELEMENT NO. 57 AND ABSORBER SECTIONS AT 10.5 MWYRS

Description: An analytical prediction of the burnout distributions in particular SM-1 fuel elements and absorber sections after 10.5 MWYR of core energy release is given. The distributions are based on the results of a one-shot, non-uniform burnout calculation, and are pre sented for both fuel and boron -10 depletion. Particular emphasis is placed on those elements removed from the SM-1 core in March 1959, since their subsequent burnup analysis by ORNL should provide a valuable check on the analytical models employed. (auth)
Date: June 1, 1959
Creator: McElligott, P.E.
Partner: UNT Libraries Government Documents Department

THE DEPLETION OF BURNABLE POISON IN ENDURANCE CALCULATIONS

Description: Methods of relating the bunnable poison concentration in a reactor to the fuel concentration during the life of the core are presented. These methcds correspond to the following ways of using bunnable poison: (1) in discrete lumps, (2) in a homogeneous rnixture with the fuel, and (3) a combination of these. Nuclear data relevant to the U/sup 235/-B/sup 10/ system are presented. (auth)
Date: March 1, 1960
Creator: Dahlberg, R.C. & Judge, F.D.
Partner: UNT Libraries Government Documents Department

Comparisons of TORT and MCNP dose calculations for BNCT treatment planning

Description: The relative merit of using a deterministic code to calculate dose distributions for BNCT applications were examined. The TORT discrete deterministic ordinated code was used in comparison to MCNP4A to calculate dose distributions for BNCT applications
Date: December 31, 1996
Creator: Ingersol, D.T.; Slater, C.O.; Williams, L.R.; Redmond, E.L., II & Zamenhof, R.G.
Partner: UNT Libraries Government Documents Department

Carborane derivative development for boron neutron capture therapy. Final report

Description: Boron Neutron Capture Therapy [BNCT] is a binary method of cancer therapy based on the capture of neutrons by a boron-10 atom [{sup 10}B]. Cytotoxic {sup 7}Li nuclei and {alpha}-particles are emitted, with a range in tissue of 9 and 5 {micro}m, respectively, about one cell diameter. The major obstacle to clinically viable BNCT is the selective localization of 5-30 ppm {sup 10}B in tumor cells required for effective therapy. A promising approach to BNCT is based on hydrophilic boron-rich oligomeric phosphate diesters, or ''trailers'' that have been shown to concentrate selectively in tumor tissue. Examples of these compounds were prepared previously at high cost using an automated DNA synthesizer. Direct synthesis methods are needed for the production of gram-scale quantities for further biological evaluation. The work accomplished as a result of the collaboration between Fluorochem, Inc. and UCLA demonstrates that short oligomers containing at least five carborane units with four phosphodiester linkages can be prepared in substantial quantities. This work was accomplished by the application of standard phosphoramidite coupling chemistry.
Date: April 1, 1999
Creator: Barnum, Beverly A.; Hao, Yan; Moore, Roger; Hawthorne, M. Frederick & Baum, Kurt
Partner: UNT Libraries Government Documents Department

Comparative Boron Isotopic Analysis

Description: S>Surface ionization results for natural boron isotopic analysis are in agreement with other recent investigations indicating a B/sup 11//B/sup 10/ atom ratio nesrer to 4.00 than the more commonly accepted value of 4.31 based on BF/ sub 3/ analysis. (auth)
Date: April 1, 1961
Creator: Goris, P.; Morgan, T. D. & Nielsen, R. A.
Partner: UNT Libraries Government Documents Department

Introduction to Neutron Coincidence Counter Design Based on Boron-10

Description: The Department of Energy Office of Nonproliferation Policy (NA-241) is supporting the project 'Coincidence Counting With Boron-Based Alternative Neutron Detection Technology' at Pacific Northwest National Laboratory (PNNL) for development of an alternative neutron coincidence counter. The goal of this project is ultimately to design, build and demonstrate a boron-lined proportional tube based alternative system in the configuration of a coincidence counter. This report, providing background information for this project, is the deliverable under Task 1 of the project.
Date: January 22, 2012
Creator: Kouzes, Richard T.; Ely, James H.; Lintereur, Azaree T. & Siciliano, Edward R.
Partner: UNT Libraries Government Documents Department

AN ALPHA COUNTER FOR UNIFORMITY MEASUREMENTS

Description: An ionization-type alpha counter is used to mensure the uniformity of thin coatings of alpha -emitting materials to plus or minus l% exclusive of statistical error. The (n, alpha ) reaction allows the counter to be used for measuring the uniformity of B/sup 10/ foils when a suitable neutron source is provided. (auth)
Date: July 1, 1957
Creator: White, F.A. & Sheffield, J.C.
Partner: UNT Libraries Government Documents Department

Boron neutron capture therapy of malignant brain tumors at the Brookhaven Medical Research Reactor

Description: Boron neutron capture therapy (BNCT) is a bimodal form of radiation therapy for cancer. The first component of this treatment is the preferential localization of the stable isotope {sup 10}B in tumor cells by targeting with boronated compounds. The tumor and surrounding tissue is then irradiated with a neutron beam resulting in thermal neutron/{sup 10}B reactions ({sup 10}B(n,{alpha}){sup 7}Li) resulting in the production of localized high LET radiation from alpha and {sup 7}Li particles. These products of the neutron capture reaction are very damaging to cells, but of short range so that the majority of the ionizing energy released is microscopically confined to the vicinity of the boron-containing compound. In principal it should be possible with BNCT to selectively destroy small nests or even single cancer cells located within normal tissue. It follows that the major improvements in this form of radiation therapy are going to come largely from the development of boron compounds with greater tumor selectivity, although there will certainly be advances made in neutron beam quality as well as the possible development of alternative sources of neutron beams, particularly accelerator-based epithermal neutron beams.
Date: December 31, 1996
Creator: Joel, D.D.; Coderre, J.A. & Chanana, A.D.
Partner: UNT Libraries Government Documents Department

Nominal effective radiation doses delivered during clinical trials of boron neutron capture therapy

Description: Boron neutron capture therapy (BNCT) is a binary system that, in theory, should selectively deliver lethal, high linear energy transfer (LET) radiation to tumor cells dispersed within normal tissues. It is based on the nuclear reaction 10-B(n, {alpha})7-Li, which occurs when the stable nucleus of boron-10 captures a thermal neutron. Due to the relatively high cross-section of the 10-B nucleus for thermal neutron capture and short ranges of the products of this reaction, tumor cells in the volume exposed to thermal neutrons and containing sufficiently high concentration of 10-B would receive a much higher radiation dose than the normal cells contained within the exposed volume. Nevertheless, radiation dose deposited in normal tissue by gamma and fast neutron contamination of the neutron beam, as well as neutron capture in nitrogen, 14-N(n,p)14-C, hydrogen, 1-H(n,{gamma})2-H, and in boron present in blood and normal cells, limits the dose that can be delivered to tumor cells. It is, therefore, imperative for the success of the BNCT the dosed delivered to normal tissues be accurately determined in order to optimize the irradiation geometry and to limit the volume of normal tissue exposed to thermal neutrons. These are the major objectives of BNCT treatment planning.
Date: December 31, 1997
Creator: Capala, J.; Diaz, A.Z. & Chanana, A.D.
Partner: UNT Libraries Government Documents Department

BOBCAT (PROGRAM NO. 56) CODE PREPARATION ANALYSIS ON THE IBM-650

Description: The BOBCAT code that is programmed for the IBM650 is described. The code facilitates the nuclear analysis of APPR-type cores by performing many of the routine calculations necessary to obtain input to various IBM-650 and IBM-704 codes. Using fuel element geometry and U/sup 235/ and B/sup 10/ loadings as input, the code prepares input to the MUFT-III and various P/sub 3/ codes as output; in addition, a large amount of detailed descriptive core data that is useful in nuclear analysis calculations is generated. (auth)
Date: August 1, 1961
Creator: Bobe, P.E. & Caton, R.L.
Partner: UNT Libraries Government Documents Department

Laminated Amorphous Silicon Neutron Detector (pre-print)

Description: An internal R&D project was conducted at the Special Technologies Laboratory (STL) of National Security Technologies, LLC (NSTec), to determine the feasibility of developing a multi-layer boron-10 based thermal neutron detector using the amorphous silicon (AS) technology currently employed in the manufacture of liquid crystal displays. The boron-10 neutron reaction produces an alpha that can be readily detected. A single layer detector, limited to an approximately 2-micron-thick layer of boron, has a theoretical sensitivity of about 3%; hence a thin multi-layer device with high sensitivity can theoretically be manufactured from single layer detectors. Working with National Renewable Energy Laboratory (NREL), an AS PiN diode alpha detector was developed and tested. The PiN diode was deposited on a boron-10 coated substrate. Testing confirmed that the neutron sensitivity was nearly equal to the theoretical value of 3%. However, adhesion problems with the boron-10 coating prevented successful development of a prototype detector. Future efforts will include boron deposition work and development of integrated AS signal processing circuitry.
Date: January 29, 2009
Creator: Harry McHugh, Howard Branz, Paul Stradins, and Yueqin Xu
Partner: UNT Libraries Government Documents Department

AN EXPERIMENT TO MEASURE EFFECTIVE DELAYED NEUTRON FRACTIONS

Description: >An experimental measurement of the effective delayed neutron fraction ( beta -bar) was made for a clean critical assembly by determining the asymptotic period associated with introduction of a known amount of reactivity. The "known amount" of reactivity was obtained by replacing, uniformly throughout the reactor, a small quantity of U/sup 235/ with an alloy of B/sup 10/ and Hf designed to match the absorption properties of U/sup 235/. The replacement was thus equivalent to a uniform reduction in nu , the number of neutrons emitted per fission from the fuel. Such a reduction introduces a reactivity change equal exactly to delta nu / nu /sub 0/. Two analyses of the experiment were made using different high energy cross sections in conjunction with four group, two dimensional diffusion theory. The measured value of beta lay between the results of these computations, the error spread (an average rms error of plus or minus 5.2%) being too great to permit any conclusion regarding the significance of the comparison. (auth)
Date: February 1, 1960
Creator: Kaplan, S. & Henry, A.F.
Partner: UNT Libraries Government Documents Department