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A compilation of information on the {sup 32}S(p, {gamma}){sup 33}Cl reaction and properties of excited levels in {sup 33}Cl

Description: This report documents a survey of the literature, and provides a compilation of data contained therein, for the {sup 32}S(p, {gamma}){sup 33}Cl reaction. Considerable attention is paid to properties of the levels in {sup 33}Cl which are located in the vicinity of excitation of the compound-nuclear system {sup 32}s + p near the proton separation energy for {sup 33}Cl. It is this particular energy region which is especially important for applications in nuclear astrophysics. Summaries of all the located references are provided and numerical data contained in them are compiled in EXFOR format where applicable.
Date: July 1, 1997
Creator: Miller, R.E. & Smith, D.L.
Partner: UNT Libraries Government Documents Department

Lithium-vanadium advanced blanket development. ITER final report on U.S. contribution: Task T219/T220

Description: The objective of this task is to develop the required data base and demonstrate the performance of a liquid lithium-vanadium advanced blanket design. The task has two main activities related to vanadium structural material and liquid lithium system developments. The vanadium alloy development activity included four subtasks: (1.1) baseline mechanical properties of non irradiated base metal and weld metal joints; (1.2) compatibility with liquid lithium; (1.3) material irradiation tests; and (1.4) development of material manufacturing and joining methods. The lithium blanket technology activity included four subtasks: (2.1) electrical insulation development and testing for liquid metal systems; (2.2) MHD pressure drop and heat transfer study for self-cooled liquid metal systems; (2.3) chemistry of liquid lithium; and (2.4) design, fabrication and testing of ITER relevant size blanket mockups. A summary of the progress and results obtained during the period 1995 and 1996 in each of the subtask areas is presented in this report.
Date: July 1, 1997
Creator: Smith, D.L. & Mattas, R.F.
Partner: UNT Libraries Government Documents Department

Nuclear Data and Measurement Series - a method to construct covariance files in ENDF/B format for criticality safety applications.

Description: Argonne National Laboratory is providing support for a criticality safety analysis project that is being performed at Oak Ridge National Laboratory. The ANL role is to provide the covariance information needed by ORNL for this project. The ENDF/B-V evaluation is being used for this particular criticality analysis. In this evaluation, covariance information for several isotopes or elements of interest to this analysis is either not given or needs to be reconsidered. For some required materials, covariance information does not exist in ENDF/B-V: {sup 233}U, {sup 236}U, Zr, Mg, Gd, and Hf. For others, existing covariance information may need to be re-examined in light of the newer ENDF/B-V evaluation and recent experimental data. In this category are the following materials: {sup 235}U, {sup 238}U, {sup 239}Pu, {sup 240}Pu, {sup 241}Pu, Fe, H, C, N, O, Al, Si, and B. A reasonable estimation of the fractional errors for various evaluated neutron cross sections from ENDF/B-V can be based on the comparisons between the major more recent evaluations including ENDF/B-VI, JENDL3.2, BROND2.2, and JEF2.2, as well as a careful examination of experimental data. A reasonable method to construct correlation matrices is proposed here. Coupling both of these considerations suggests a method to construct covariances files in ENDF/B format that can be used to express uncertainties for specific ENDF/B-V cross sections.
Date: July 30, 1999
Creator: Naberejnev, D.G. & Smith, D.L.
Partner: UNT Libraries Government Documents Department

The COBRA accelerator pulsed-power driver for Cornell/Sandia ICF research

Description: This paper introduces and describes the new Cornell Beam Research Accelerator, COBRA, the result of a three and one-half year collaboration. The flexible 4 to 5-MV, 100 to 250-kA, 46-ns pulse width accelerator is based on a four-cavity Inductive Voltage Adder (IVA) design. In addition to being a mix of new and existing components, COBRA is unique in the sense that each cavity is driven by a single pulse forming line, and the IVA output polarity may be reversed by rotating the cavities 1800 about their vertical axis. Our tests with negative high voltage on the inner MITL stalk indicate that the vacuum power flow has established reasonable azimuthal symmetry within about 2 ns (or 0.6 m) after the cavity output cap. Preliminary results with the accelerator, single cavity, and MITL are presented alone, with the design details and circuit model predictions.
Date: July 1, 1995
Creator: Smith, D.L.; Ingwersen, P.; Bennett, L.F.; Boyes, J.D.; Anderson, D.E.; Greenly, J.B. et al.
Partner: UNT Libraries Government Documents Department

Stress-corrosion cracking susceptibility of V-15Cr-5Ti in pressurized water at 288/sup 0/C

Description: The stress-corrosion cracking susceptibility of V-15Cr-5Ti in pressurized water at 288/sup 0/C has been evaluated by means of constant extension rate tensile (CERT) tests in a refreshed autoclave system. The test environments included high-purity water as well as water containing SO/sub 4//sup 2 -/ and NO/sub 3//sup -/ impurities at a concentration of 10 wppM. Strain rates from 1 x 10/sup -6/ to 5 x 10/sup -8/ s/sup -1/ were employed, and dissolved oxygen levels ranged from <0.005 to 7.9 wppM. Test times were from 3.2 to 619 h. No stress corrosion cracking was observed under any of the test conditions. These results were analyzed using measured electrochemical potentials, available Pourbaix diagram information, and the observed oxidation behavior. 7 refs., 5 figs., 1 tab.
Date: July 1, 1987
Creator: Diercks, D.R. & Smith, D.L.
Partner: UNT Libraries Government Documents Department

Neutron activation cross sections for copper, europium, hafnium, iron, nickel, silver, terbium and titanium from the Argonne, Los Alamos and Jaeri collaboration

Description: Several fast-neutron activation reactions for copper, europium, hafnium, iron, nickel, silver, terbium and titanium that are important to fusion energy have been investigated in three distinct neutron fields generated by accelerators at Argonne National Laboratory and Los Alamos National Laboratory, USA, and Japan Atomic Energy Research Institute, Tokai, Japan. Final differential cross-sections at 14.7 MeV and integral cross sections for the Be(d,n) thick-target spectrum produced by 7-MeV deutrons are reported here. Data have also been acquired for neutron energies near 10 MeV. However, these latter results will be made available after problems associated with determining the neutron-energy scale and interpreting the quasi-differential cross-sections measured near threshold are resolved.
Date: July 1, 1995
Creator: Meadows, J.W.; Smith, D.L.; Greenwood, L.R.; Haight, R.C.; Ideda, Y. & Konno, C.
Partner: UNT Libraries Government Documents Department

NALDA (Naval Aviation Logistics Data Analysis) CAI (computer aided instruction)

Description: Data Systems Engineering Organization (DSEO) personnel developed a prototype computer aided instruction CAI system for the Naval Aviation Logistics Data Analysis (NALDA) system. The objective of this project was to provide a CAI prototype that could be used as an enhancement to existing NALDA training. The CAI prototype project was performed in phases. The task undertaken in Phase I was to analyze the problem and the alternative solutions and to develop a set of recommendations on how best to proceed. The findings from Phase I are documented in Recommended CAI Approach for the NALDA System (Duncan et al., 1987). In Phase II, a structured design and specifications were developed, and a prototype CAI system was created. A report, NALDA CAI Prototype: Phase II Final Report, was written to record the findings and results of Phase II. NALDA CAI: Recommendations for an Advanced Instructional Model, is comprised of related papers encompassing research on computer aided instruction CAI, newly developing training technologies, instructional systems development, and an Advanced Instructional Model. These topics were selected because of their relevancy to the CAI needs of NALDA. These papers provide general background information on various aspects of CAI and give a broad overview of new technologies and their impact on the future design and development of training programs. The paper within have been index separately elsewhere.
Date: July 1, 1990
Creator: Handler, B.H. (Oak Ridge K-25 Site, TN (USA)); France, P.A.; Frey, S.C.; Gaubas, N.F.; Hyland, K.J.; Lindsey, A.M. et al.
Partner: UNT Libraries Government Documents Department

Characteristics of the neutron flux from a D-Li neutron source

Description: A D-Li neutron source produces a high flux of neutrons which can be used for testing fusion materials. The characteristics exhibited by the neutron flux inside the test assembly volume of a D-Li neutron source irradiation facility is a function of several design options, such as deuteron energy, beam current, beam cross sectional area, and lithium target configuration, among others. The influence of each of these parameters on the overall performance of the machine, in terms of best results for irradiation of materials for fusion applications, can be inferred by scoping their impact on the uncollided neutron flux magnitude and distribution. The first part of this paper describes an analysis performed on the uncollided neutron flux (without material inside the test assembly region) for different beam-target configurations for determining the effect of varying the elements of the configuration on the uncollided neutron flux gradient. The second section deals with the neutron energy spectrum from the D-Li reaction and a brief discussion on {open_quotes}fusion reactor spectrum{close_quotes} is also presented. In the third section results from calculations of the volume with uncollided neutron above a threshold value are presented.
Date: July 1, 1994
Creator: Gomes, I. & Smith, D. L.
Partner: UNT Libraries Government Documents Department

Characterization of an accelerator neutron source based on the Be(d,n) reaction

Description: Small accelerator neutron sources offer considerable potential for applied neutron radiography applications. Among the desirable features are relatively low costs, limited operating hazards, opportunities for tailoring primary neutron spectra, compactness and portability, and modest licensing requirements (compared to fission reactors). However, exploitation of this potential has been somewhat limited, in part, by incomplete knowledge of the primary-neutron yields and energy spectra from the favorable source reactions. This work describes an extensive experimental determination of zero-degree neutron yields and energy spectra from the {sup 9}Be(d,n) {sup 10}B source reaction, for incident deuterons of 2.6 to 7.0 MeV on a thick beryllium metal target. This information was acquired by means of time-of-flight measurements that were conducted with a calibrated uranium fission detector. Tables and plots of neutron-producing reaction data are presented. This information provides input which will be essential for applications involving the primary spectrum as well as for the design of neutron moderators and for calculation of thermal-neutron yield factors. Such analyses will be prerequisites in assessing the suitability of this source for various possible neutron radiography applications and, also, for assisting in the design of appropriate detectors to be used in neutron imaging devices.
Date: July 1, 1992
Creator: Meadows, J. W. & Smith, D. L.
Partner: UNT Libraries Government Documents Department

Energy-differential cross section measurement for the /sup 51/V(n,. cap alpha. )/sup 48/Sc reaction

Description: The activation method was used to measure cross sections for the /sup 51/V(n,..cap alpha..)/sup 48/Sc reaction in the threshold region, from 5.515 MeV up to 9.567 MeV. Twenty approximately-monoenergetic cross section values were obtained in this experiment. These data points span the energy region at roughly equal intervals. The experimental resolutions were in the range 0.153 to 0.233 MeV (FWHM). The present differential data cover approx. 50% of the total integral response of this reaction for the standard /sup 235/U thermal-neutron-induced-fission neutron spectrum, and approx. 44% of the corresponding response for the standard /sup 252/Cf spontaneous-fission neutron spectrum. Over the range 7.6 to 9.5 MeV the present experimental cross sections are noticeably larger (e.g., by approx. 50% at approx. 8.6 MeV) than the corresponding values from the ENDF/B-V evaluation. From approx. 6.7 to 7.5 MeV, the present values are somewhat below those of ENDF/B-V. At still lower energies the agreement is reasonably good considering the uncertainties introduced by energy scale definition very near the effective threshold where the cross section varies rapidly with neutron energy. Calculated integral cross sections based in part on the present work agree reasonably well within errors with reported integral results, provided that the reported data are renormalized to conform with recently-accepted values for appropriate standard reactions. 70 references.
Date: July 1984
Creator: Kanno, I.; Meadows, J. W. & Smith, D. L.
Partner: UNT Libraries Government Documents Department

Swelling and tensile properties of neutron-irradiated vanadium alloys

Description: Vanadium-base alloys are candidates for use as structural material in magnetic fusion reactors. In comparison to other candidate structural materials (e.g., Type 316 stainless and HT-9 ferritic steels), vanadium-base alloys such as V-15Cr-5Ti and V-20Ti have intrinsically lower long-term neutron activation, neutron irradiation after-heat, biological hazard potential, and neutron-induced helium and hydrogen transmutation rates. Moreover, vanadium-base alloys can withstand a higher surface-heat, flux than steels because of their lower thermal stress factor. In addition to having these favorable neutronic and physical properties, a candidate alloy for use as structural material in a fusion reactor must have dimensional stability, i.e., swelling resistance, and resistance to embrittlement during the reactor lifetime at a level of structural strength commensurate with the reactor operating temperature and structural loads. In this paper, we present experimental results on the swelling and tensile properties of several vanadium-base alloys after irradiation at 420, 520, and 600{degree}C to neutron fluences ranging from 0.3 to 1.9 {times} 10{sup 27} neutrons/m{sup 2} (17 to 114 atom displacements per atom (dpa)).
Date: July 1, 1990
Creator: Loomis, B.A. & Smith, D.L.
Partner: UNT Libraries Government Documents Department