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EQUIPOISE-3: A TWO DIMENSIONAL, TWO-GROUP, NEUTRON DIFFUSION CODE FOR THE IBM-7090 COMPUTER

Description: EQUIPOISE-3 is an IBM-7090 FORTRAN programmed code for the solution of two-group, two-dimensional, neutron diffusion equations. A maximum of 2l00 mesh points may be used, and the code will solve problems in either rectangular or cylindrical geometry. Logarithmic derivative boundary conditions are allowed, and removal of neutrons from both groups is permitted. Adjoint fluxes with the associated fluxadjoint flux regional integrals may be calculated automatically if desired. A constant buckling, g… more
Date: February 21, 1962
Creator: Fowler, T.B. & Tobias, M.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear Stewardship Research.

Description: This report covers the period from June 2005 through May 2006. During this, the third year of our program, our research has focused mainly on applying the surrogate reaction technique and our newly developed surrogate ratio method to deduce neutron induced fission cross sections on uranium nuclei. The year has been marked by continued scientific progress, by the arrival of new personnel, by a growth in the numbers of students working in the group and by a continuation of our experimental progra… more
Date: June 21, 2006
Creator: Beausang, C. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Crack growth rates and fracture toughness of irradiated austenitic stainless steels in BWR environments.

Description: In light water reactors, austenitic stainless steels (SSs) are used extensively as structural alloys in reactor core internal components because of their high strength, ductility, and fracture toughness. However, exposure to high levels of neutron irradiation for extended periods degrades the fracture properties of these steels by changing the material microstructure (e.g., radiation hardening) and microchemistry (e.g., radiation-induced segregation). Experimental data are presented on the frac… more
Date: January 21, 2008
Creator: Chopra, O. K. & Shack, W. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of Irradiation hardening of Unalloyed and ODS molybdenum during neurtron irradiation to low doses at 300C and 600C

Description: Unalloyed molybdenum and Oxide Dispersion Strengthened (ODS) molybdenum were irradiated at 300 C and 600 C in the high flux isotope reactor (HFIR) to neutron fluences of 0.2, 2.1, and 24.3 x 10{sup 24} n/m{sup 2} (E > 0.1 MeV), producing damage levels of 0.01, 0.1 and 1.3 Mo-dpa. Hardness measurements, electrical resistivity measurements, tensile testing, and Transmission Electron Microscopy (TEM) were used to assess the defect structure. Irradiation hardening was evident even at a damage le… more
Date: November 21, 2007
Creator: Cockeran, B. V. & Smith, R. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Preliminary Materials Selection Issues for the Next Generation Nuclear Plant Reactor Pressure Vessel.

Description: In the coming decades, the United States and the entire world will need energy supplies to meet the growing demands due to population increase and increase in consumption due to global industrialization. One of the reactor system concepts, the Very High Temperature Reactor (VHTR), with helium as the coolant, has been identified as uniquely suited for producing hydrogen without consumption of fossil fuels or the emission of greenhouse gases [Generation IV 2002]. The U.S. Department of Energy (DO… more
Date: March 21, 2007
Creator: Natesan, K.; Majumdar, S.; Shankar, P. S. & Shah, V. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental Component Characterization, Monte-Carlo-Based Image Generation and Source Reconstruction for the Neutron Imaging System of the National Ignition Facility

Description: The Neutron Imaging System (NIS) is one of seven ignition target diagnostics under development for the National Ignition Facility. The NIS is required to record hot-spot (13-15 MeV) and downscattered (6-10 MeV) images with a resolution of 10 microns and a signal-to-noise ratio (SNR) of 10 at the 20% contour. The NIS is a valuable diagnostic since the downscattered neutrons reveal the spatial distribution of the cold fuel during an ignition attempt, providing important information in the case of… more
Date: August 21, 2007
Creator: Barrera, C. A. & Moran, M. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Edge Plasma Analysis for Liquid-wall MFE Concepts

Description: A thick flowing layer of liquid (e.g., flibe-a molten salt, or Sn{sub 80}Li{sub 20}--a liquid metal) protects the structural walls of the magnetic fusion configuration so that they can last the life of the plant even with intense 14 MeV neutron bombardment from the D-T fusion reaction, The surface temperature of the liquid rises as it passes from the inlet nozzles to the exit nozzles due to absorption of line and bremsstrahlung radiation, and neutrons. The surface temperature can be reduced by … more
Date: September 21, 2000
Creator: Moir, R W; Rensink, M & Rognlien, T D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Godiva and Juliet Diagnostics CED-1 (IER-176)

Description: A suite of diagnostics are being proposed for use in the Juliet experiment (IER-128). In order to calibrate and test the diagnostics prior to use, the LLNL calibration facility and Godiva pulsed reactor will be used to provide intense sources of neutrons and gammas. Due to the similarities of the Godiva and Juliet radiation fields, the diagnostics being developed and tested for Juliet can also play an on-going role in diagnostics for Godiva as well as, perhaps, other critical assembly experimen… more
Date: December 21, 2011
Creator: Scorby, J C
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fast-neutron detector for use as a criticality monitor

Description: To increase the reliability of the criticality monitoring system in a diagnostic chemistry area and to reduce the number of false alarms, a new monitoring system was built using a fast-neutron detector. This paper outlines the design requirements, describes the plastic scintillation detector system as it was built, and reports on the results of several months of operation. The new monitor has proven much more useful than the gamma-detector system it replaced.
Date: September 21, 1976
Creator: Friesen, R. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Evaluation of LLNL's Nuclear Accident Dosimeters at the CALIBAN Reactor September 2010

Description: The Lawrence Livermore National Laboratory uses neutron activation elements in a Panasonic TLD holder as a personnel nuclear accident dosimeter (PNAD). The LLNL PNAD has periodically been tested using a Cf-252 neutron source, however until 2009, it was more than 25 years since the PNAD has been tested against a source of neutrons that arise from a reactor generated neutron spectrum that simulates a criticality. In October 2009, LLNL participated in an intercomparison of nuclear accident dosimet… more
Date: June 21, 2011
Creator: Hickman, D P; Wysong, A R; Heinrichs, D P; Wong, C T; Merritt, M J; Topper, J D et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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AVNG as a Test Case for Cooperative Design

Description: Designing a measurement system that might be used in a nuclear facility is a challenging, if not daunting, proposition. The situation is made more complicated when the system needs to be designed to satisfy the disparate requirements of a monitoring and a host party - a relationship that could prove to be adversarial. The cooperative design of the elements of the AVNG (Attribute Verification with Neutrons and Gamma Rays) system served as a crucible that exercised the possible pitfalls in the de… more
Date: May 21, 2010
Creator: Luke, S J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An Overview of Recent Logging Research at The University of Texas Petroleum Engineering Department

Description: Logging research at The University of Texas has been carried out in several areas. We have studied how rock resistivity varies with water saturation when other variables, such as rock wettability, stress, saturation history, and shale content are varied. Both experimental and theoretical work have been done. Rock wettability (oil or water wet) has by far the largest effect. Shale content and saturation history are also important. Rock stress is the least important, at least in the Berea sandsto… more
Date: March 21, 1989
Creator: Dunlap, H. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Global Error Bounds for the Petrov-Galerkin Discretization of the Neutron Transport Equation

Description: In this paper, we prove that the numerical solution of the mono-directional neutron transport equation by the Petrov-Galerkin method converges to the true solution in the L{sup 2} norm at the rate of h{sup 2}. Since consistency has been shown elsewhere, the focus here is on stability. We prove that the system of Petrov-Galerkin equations is stable by showing that the 2-norm of the inverse of the matrix for the system of equations is bounded by a number that is independent of the order of the ma… more
Date: January 21, 2005
Creator: Chang, B.; Brown, P.; Greenbaum, A. & Machorro, E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Report for General Research December 26, 1950 to April 16, 1951 (Supporting Research Volume)

Description: This volume presents the quarterly results of that portion of the research and development which is directed towards establishing new techniques and instruments and towards improving present methods for determining levels of radioactivity accurately and safely. The locally developed amplifier of high gain and of wide dynamic range has been shown to provide plateaus suitable for the simultaneous counting of alpha and beta particles. Commercially available amplifiers have failed to exhibit suitab… more
Date: May 21, 1951
Creator: Haring, M. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Extreme Radiation Hardness and Space Qualification of AlGaN Optoelectronic Devices

Description: Unprecedented radiation hardness and environment robustness are required in the new generation of high energy density physics (HEDP) experiments and deep space exploration. National Ignition Facility (NIF) break-even shots will have a neutron yield of 1015 or higher. The Europa Jupiter System Mission (EJSM) mission instruments will be irradiated with a total fluence of 1012 protons/cm2 during the space journey. In addition, large temperature variations and mechanical shocks are expected in thes… more
Date: September 21, 2010
Creator: Sun, Ke-Xun; Balakrishnan, Kathik; Hultgren, Eric; Goebel, John; Bilenko, Yuri; Yang, Jinwei et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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EFFECTS OF IRRADIATION ON STAINLESS STEEL-CLAD UO$sup 2$ PELLETS IN HELIUM OR CARBON DIOXIDE

Description: Uranium dioxide pellets sealed in Type 316 stainless steel containers with a helium gas were irradiated in helium and in C0/sub 2/ in thermal fluxes or the order of 1 x 10/sup 13/ n/(cm/sup 2/)(sec). Cladding-surface temperatures were reportedly between 1200 and about 1800 F. The hot-cell examination performed by BMI showed that there were no obvious effects of the irradiation on the specimen tested in helium. However, the specimen irradiated in the presence of C0/sub 2/ exhibited severe claddi… more
Date: April 21, 1959
Creator: Lamale, G.E.; Gates, J.E. & Dickerson, R.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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FIRE, A Test Bed for ARIES-RS/AT Advanced Physics and Plasma Technology

Description: The overall vision for FIRE [Fusion Ignition Research Experiment] is to develop and test the fusion plasma physics and plasma technologies needed to realize capabilities of the ARIES-RS/AT power plant designs. The mission of FIRE is to attain, explore, understand and optimize a fusion dominated plasma which would be satisfied by producing D-T [deuterium-tritium] fusion plasmas with nominal fusion gains {approx}10, self-driven currents of {approx}80%, fusion power {approx}150-300 MW, and pulse l… more
Date: October 21, 2004
Creator: Meade, Dale M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Final report: DOE Grant ''Development of focusing monochromators for neutron scattering instruments'' (DE-FG02-96ER45599)

Description: Bent crystal monochromators were developed for the neutron scattering community: (1) doubly focusing bulk silicon, for high-resolution neutron diffraction; (2) doubly focusing multi-wafer silicon, for residual stress instruments; (3) silicon-wafer: (a) with pneumatic spherical bending, (b) with mechanical cylindrical bending, (c) with mechanical two-dimensional bending, for high-resolution three-axis spectrometry; (4) doubly focusing multi-wafer silicon, for epithermal (eV range) neutrons; (5) … more
Date: March 21, 2000
Creator: Popovici, Mihai P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Oak Ridge Multiple Attribute System (ORMAS) for Pu, HEU, HE, Chemical Agents, and Drugs

Description: The concept for the Oak Ridge Multiple Attribute System (ORMAS) is a Nuclear Materials Identification System (NMIS) time-dependent coincidence processor that incorporates gamma ray spectrometry and utilizes a small, lightweight, portable DT neutron (14.1 MeV) generator (1 x 10{sup 8} n/s), proton recoil scintillation detectors, and a gamma ray detector (HPGe). ORMAS is based on detecting fission neutrons and gamma rays from inherent source fission, fission induced by the external DT source, gam… more
Date: September 21, 2001
Creator: Mihalczo, J.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutron Scattering Instrumentation for Measurement of Melt Structure

Description: This Phase II research project was focused on constructing and testing a facility for the measurement of the structure of hot solid and liquid materials under extreme conditions using neutron diffraction. The work resulted in measurements at temperatures of 3300 K, the highest ever performed in a neutron beam. Work was performed jointly by Containerless Research, Inc. and Argonne National Laboratory with significant interactions with engineers and scientists at the under construction-SNS facili… more
Date: October 21, 2004
Creator: Weber, Richard & Benmore, Christopher
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Isotopically controlled semiconductors

Description: Semiconductor bulk crystals and multilayer structures with controlled isotopic composition have attracted much scientific and technical interest in the past few years. Isotopic composition affects a large number of physical properties, including phonon energies and lifetimes, bandgaps, the thermal conductivity and expansion coefficient and spin-related effects. Isotope superlattices are ideal media for self-diffusion studies. In combination with neutron transmutation doping, isotope control off… more
Date: December 21, 2001
Creator: Haller, Eugene E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radiation-Neutralization of Stored Biological Warfare Agents with Low-Yield Nuclear Warheads

Description: MCNP Monte Carlo radiation transport computations were performed exploring the capability of low-yield nuclear fusion and fission warheads to neutralize biological warfare agents with the radiation dose deposited in the agent by the prompt neutron output. The calculations were done for various typical storage configurations on the ground in the open air or in a warehouse building. This application of nuclear weapons is motivated by the observation that, for some military scenarios, the nuclear … more
Date: August 21, 2000
Creator: Kruger, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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