Resource Type

Use of gamma ray strength functions for predicting the neutron capture cross section of /sup 88/Y (open access)

Use of gamma ray strength functions for predicting the neutron capture cross section of /sup 88/Y

The present study indicates that the estimation of the gamma-ray strength function is the approach least subject to error when unmeasured capture cross sections are to be computed. An estimate is given for the /sup 88/..gamma..(n,..gamma..) cross section.
Date: July 29, 1977
Creator: Gardner, D. G. & Gardner, M. A.
System: The UNT Digital Library
Simulation of landscape disturbances and the effect of climatic change. Final report, July 15, 1989--July 14, 1990 (open access)

Simulation of landscape disturbances and the effect of climatic change. Final report, July 15, 1989--July 14, 1990

The purpose of this research is to understand how changes in climate may affect the structure of landscapes that are subject to periodic disturbances. A general model useful for examining the linkage between climatic change and landscape change has been developed. The model makes use of synoptic climatic data, a geographical information system (GRASS), field data on the location of disturbance patches, simulation code written in the SIMSCRIPT language, and a set of landscape structure analysis programs written specifically for this research project. A simplified version of the model, lacking the climatic driver, has been used to analyze how changes in disturbance regimes (in this case settlement and fire suppression) affect landscape change. Landscape change lagged in its response to changes in the disturbance regime, but the lags differed depending upon the character of the change and the particular measure considered. The model will now be modified for use in a specific setting to analyze the effects of changes in climate on the structure of flood-disturbed patches along the Animas River, Colorado.
Date: January 29, 1993
Creator: Baker, W. L.
System: The UNT Digital Library
Simulation of landscape disturbances and the effect of climatic change (open access)

Simulation of landscape disturbances and the effect of climatic change

The purpose of this research is to understand how changes in climate may affect the structure of landscapes that are subject to periodic disturbances. A general model useful for examining the linkage between climatic change and landscape change has been developed. The model makes use of synoptic climatic data, a geographical information system (GRASS), field data on the location of disturbance patches, simulation code written in the SIMSCRIPT language, and a set of landscape structure analysis programs written specifically for this research project. A simplified version of the model, lacking the climatic driver, has been used to analyze how changes in disturbance regimes (in this case settlement and fire suppression) affect landscape change. Landscape change lagged in its response to changes in the disturbance regime, but the lags differed depending upon the character of the change and the particular measure considered. The model will now be modified for use in a specific setting to analyze the effects of changes in climate on the structure of flood-disturbed patches along the Animas River, Colorado.
Date: January 29, 1993
Creator: Baker, W.L.
System: The UNT Digital Library
TANK 4 CHARACTERIZATION, SETTLING, AND WASHING STUDIES (open access)

TANK 4 CHARACTERIZATION, SETTLING, AND WASHING STUDIES

A sample of PUREX sludge from Tank 4 was characterized, and subsequently combined with a Tank 51 sample (Tank 51-E1) received following Al dissolution, but prior to a supernate decant by the Tank Farm, to perform a settling and washing study to support Sludge Batch 6 preparation. The sludge source for the majority of the Tank 51-E1 sample is Tank 12 HM sludge. The Tank 51-E1 sample was decanted by SRNL prior to use in the settling and washing study. The Tank 4 sample was analyzed for chemical composition including noble metals. The characterization of the Tank 51-E1 sample, used here in combination with the Tank 4 sample, was reported previously. SRNL analyses on Tank 4 were requested by Liquid Waste Engineering (LWE) via Technical Task Request (TTR) HLE-TTR-2009-103. The sample preparation work is governed by Task Technical and Quality Assurance Plan (TTQAP), and analyses were controlled by an Analytical Study Plan and modifications received via customer communications. Additional scope included a request for a settling study of decanted Tank 51-E1 and a blend of decanted Tank 51-E1 and Tank 4, as well as a washing study to look into the fate of undissolved sulfur observed during the Tank 4 …
Date: September 29, 2009
Creator: Bannochie, C.; Pareizs, J.; Click, D. & Zamecnik, J.
System: The UNT Digital Library
Use of Electrochemical Noise to Assess Corrosion in Kraft Continuous Digesters (open access)

Use of Electrochemical Noise to Assess Corrosion in Kraft Continuous Digesters

Electrochemical noise (EN) probes were deployed in two continuous kraft digesters at a variety of locations representative of corrosion throughout the vessels. Current and potential noise, the temperature at each probe location, and the value of up to 60 process parameters (flow rates, liquor chemistry, etc.) were monitored continuously during each experiment. The results indicate that changes in furnish composition and process upsets were invariably associated with concurrent substantial changes in EN activity throughout the vessels. Post-test evaluation of the mild steel electrode materials in both vessels confirmed general corrosion of a magnitude consistent with historical trends in the respective vessels as well as values qualitatively (and semi-quantitatively) related to EN current sums for each electrode pair. Stainless steel electrodes representing 309LSi and 312 overlay repairs exhibited zero wastage corrosion--as did the actual overlays--but the EN data indicated periodic redox activity on the stainless steel that varied with time and position within the vessel. Little or no correlation between EN probe activity and other operational variables was observed in either vessel. Additional details for each digester experiment are summarized.
Date: November 29, 2004
Creator: Pawel, S.J.
System: The UNT Digital Library
Far-Field Accumulation of Fissile Material From Waste Packages Containing Plutonium Disposition Waste Form (open access)

Far-Field Accumulation of Fissile Material From Waste Packages Containing Plutonium Disposition Waste Form

The objective of this calculation is to estimate the quantity of fissile material that could accumulate in fractures in the rock beneath plutonium-ceramic (Pu-ceramic) and Mixed-Oxide (MOX) waste packages (WPs) as they degrade in the potential monitored geologic repository at Yucca Mountain. This calculation is to feed another calculation (Ref. 31) computing the probability of criticality in the systems described in Section 6 and then ultimately to a more general report on the impact of plutonium on the performance of the proposed repository (Ref. 32), both developed concurrently to this work. This calculation is done in accordance with the development plan TDP-DDC-MD-000001 (Ref. 9), item 5. The original document described in item 5 has been split into two documents: this calculation and Ref. 4. The scope of the calculation is limited to only very low flow rates because they lead to the most conservative cases for Pu accumulation and more generally are consistent with the way the effluent from the WP (called source term in this calculation) was calculated (Ref. 4). Ref. 4 (''In-Drift Accumulation of Fissile Material from WPs Containing Plutonium Disposition Waste Forms'') details the evolution through time (breach time is initial time) of the chemical composition of …
Date: September 29, 2000
Creator: Nicot, J.P.
System: The UNT Digital Library
Development of Novel Water-Gas Shift Membrane Reactor (open access)

Development of Novel Water-Gas Shift Membrane Reactor

None
Date: December 29, 2004
Creator: Ho, W. S. Winston
System: The UNT Digital Library
Development of Novel Water-Gas Shift Membrane Reactor (open access)

Development of Novel Water-Gas Shift Membrane Reactor

This report summarizes the objectives, technical barrier, approach, and accomplishments for the development of a novel water-gas-shift (WGS) membrane reactor for hydrogen enhancement and CO reduction. We have synthesized novel CO{sub 2}-selective membranes with high CO{sub 2} permeabilities and high CO{sub 2}/H{sub 2} and CO{sub 2}/CO selectivities by incorporating amino groups in polymer networks. We have also developed a one-dimensional non-isothermal model for the countercurrent WGS membrane reactor. The modeling results have shown that H{sub 2} enhancement (>99.6% H{sub 2} for the steam reforming of methane and >54% H{sub 2} for the autothermal reforming of gasoline with air on a dry basis) via CO{sub 2} removal and CO reduction to 10 ppm or lower are achievable for synthesis gases. With this model, we have elucidated the effects of system parameters, including CO{sub 2}/H{sub 2} selectivity, CO{sub 2} permeability, sweep/feed flow rate ratio, feed temperature, sweep temperature, feed pressure, catalyst activity, and feed CO concentration, on the membrane reactor performance. Based on the modeling study using the membrane data obtained, we showed the feasibility of achieving H{sub 2} enhancement via CO{sub 2} removal, CO reduction to {le} 10 ppm, and high H{sub 2} recovery. Using the membrane synthesized, we have obtained …
Date: December 29, 2004
Creator: Ho, W. S. Winston
System: The UNT Digital Library
Theoretical and analog studies of the effects of nonlinear stability derivatives on the longitudinal motions of an aircraft in response to step control deflections and to the influence of proportional automatic control (open access)

Theoretical and analog studies of the effects of nonlinear stability derivatives on the longitudinal motions of an aircraft in response to step control deflections and to the influence of proportional automatic control

Through theoretical and analog results the effects of two nonlinear stability derivatives on the longitudinal motions of an aircraft have been investigated. Nonlinear functions of pitching-moment and lift coefficients with angle of attack were considered. Analog results of aircraft motions in response to step elevator deflections and to the action of the proportional control systems are presented. The occurrence of continuous hunting oscillations was predicted and demonstrated for the attitude stabilization system with proportional control for certain nonlinear pitching-moment variations and autopilot adjustments.
Date: December 29, 1950
Creator: Curfman, Howard J., Jr.
System: The UNT Digital Library
High Temperture Ceramic Fuel Cell Measurement and Diagnostics for Application to Solid Oxide Fuel Cell Systems (open access)

High Temperture Ceramic Fuel Cell Measurement and Diagnostics for Application to Solid Oxide Fuel Cell Systems

This paper is the result of an extensive literature review and technology evaluation, performed to determine the status of sensors and measurement technologies.
Date: October 29, 2001
Creator: Koehler, Theresa M.; Jarrell, Donald B. & Bond, Leonard J.
System: The UNT Digital Library
High Temperature Ceramic Fuel Cell Measurement and Diagnostics for Application to Solid Oxide Fuel Cell Systems (open access)

High Temperature Ceramic Fuel Cell Measurement and Diagnostics for Application to Solid Oxide Fuel Cell Systems

This paper is the result of an extensive literature review and technology evaluation, performed to determine the status of sensors and measurement technologies.
Date: October 29, 2001
Creator: Koehler, Theresa M; Jarrell, Donald B & Bond, Leonard J
System: The UNT Digital Library
MOUND LABORATORY PROGRESS REPORT FOR JUNE 1962 (open access)

MOUND LABORATORY PROGRESS REPORT FOR JUNE 1962

Research and development progress is reported on plastics, analytical methods, radioelements, isotope separation and purification, reactor fuels and materials developmert, Ranger x-ray sensor program, and SNAP a. (M.C.G.)
Date: June 29, 1962
Creator: Grove, G.R.; Jones, L.V. & Eichelberger, J.F.
System: The UNT Digital Library
Computation of Multi-region Relaxed Magnetohydrodynamic Equilibria (open access)

Computation of Multi-region Relaxed Magnetohydrodynamic Equilibria

We describe the construction of stepped-pressure equilibria as extrema of a multi-region, relaxed magnetohydrodynamic (MHD) energy functional that combines elements of ideal MHD and Taylor relaxation, and which we call MRXMHD. The model is compatible with Hamiltonian chaos theory and allows the three-dimensional MHD equilibrium problem to be formulated in a well-posed manner suitable for computation. The energy-functional is discretized using a mixed finite-element, Fourier representation for the magnetic vector potential and the equilibrium geometry; and numerical solutions are constructed using the stepped-pressure equilibrium code, SPEC. Convergence studies with respect to radial and Fourier resolution are presented.
Date: March 29, 2013
Creator: S.R. Hudson, R.L. Dewar, G. Dennis, M.J. Hole, M. McGann, G. von Nessi and S. Lazerson
System: The UNT Digital Library
REPOSITORY NEAR-FIELD THERMAL MODELING UPDATEINCLUDING ANALYSIS OF OPEN MODE DESIGN CONCEPTS - DRAFT REV. M (open access)

REPOSITORY NEAR-FIELD THERMAL MODELING UPDATEINCLUDING ANALYSIS OF OPEN MODE DESIGN CONCEPTS - DRAFT REV. M

None
Date: July 29, 2012
Creator: Greenberg, H R; Sutton, M; Sharma, M & Barnwell, A V
System: The UNT Digital Library
Science and Technology Review December 2010 (open access)

Science and Technology Review December 2010

This month's issue has the following articles: (1) More Insight to Better Understand Climate Change - Commentary by Tomas Diaz de la Rubia; (2) Strengthening Our Understanding of Climate Change - Researchers at the Center for Accelerator Mass Spectrometry are working to better understand climate variation and sharpen the accuracy of predictive models; (3) Precision Diagnostics Tell All - The National Ignition Facility relies on sophisticated diagnostic instruments for measuring the key physical processes that occur in high-energy-density experiments; (4) Quick Detection of Pathogens by the Thousands - Livermore scientists have developed a device that can simultaneously identify thousands of viruses and bacteria within 24 hours; and (5) Carbon Dioxide into the Briny Deep - A proposed technique for burying carbon dioxide underground could help mitigate the effects of this greenhouse gas while producing freshwater.
Date: October 29, 2010
Creator: Blobaum, K M
System: The UNT Digital Library
Hazardous waste treatment and environmental remediation research (open access)

Hazardous waste treatment and environmental remediation research

Los Alamos National Laboratory (LANL) is currently evaluating hazardous waste treatment and environmental remediation technologies in existence and under development to determine applicability to remediation needs of the DOE facilities under the Albuquerque Operations Office and to determine areas of research need. To assist LANL is this effort, Science Applications International Corporation (SAIC) conducted an assessment of technologies and monitoring methods that have been demonstrated or are under development. The focus of this assessment is to: (1) identify existing technologies for hazardous waste treatment and environmental remediation of old waste sites; (2) identify technologies under development and the status of the technology; (3) assess new technologies that need development to provide adequate hazardous waste treatment and remedial action technologies for DOD and DOE sites; and (4) identify hazardous waste and remediation problems for environmental research and development. There are currently numerous research and development activities underway nationwide relating to environmental contaminants and the remediation of waste sites. To perform this effort, SAIC evaluated current technologies and monitoring methods development programs in EPA, DOD, and DOE, as these are the primary agencies through which developmental methods are being demonstrated. This report presents this evaluation and provides recommendations as to pertinent research …
Date: September 29, 1989
Creator: unknown
System: The UNT Digital Library
Bibliographical database of radiation biological dosimetry and risk assessment: Part 1, through June 1988 (open access)

Bibliographical database of radiation biological dosimetry and risk assessment: Part 1, through June 1988

This database was constructed to support research in radiation biological dosimetry and risk assessment. Relevant publications were identified through detailed searches of national and international electronic databases and through our personal knowledge of the subject. Publications were numbered and key worded, and referenced in an electronic data-retrieval system that permits quick access through computerized searches on publication number, authors, key words, title, year, and journal name. Photocopies of all publications contained in the database are maintained in a file that is numerically arranged by citation number. This report of the database is provided as a useful reference and overview. It should be emphasized that the database will grow as new citations are added to it. With that in mind, we arranged this report in order of ascending citation number so that follow-up reports will simply extend this document. The database cite 1212 publications. Publications are from 119 different scientific journals, 27 of these journals are cited at least 5 times. It also contains reference to 42 books and published symposia, and 129 reports. Information relevant to radiation biological dosimetry and risk assessment is widely distributed among the scientific literature, although a few journals clearly dominate. The four journals publishing the …
Date: August 29, 1988
Creator: Straume, T.; Ricker, Y. & Thut, M.
System: The UNT Digital Library
Gas-Cooled Reactor Project Semiannual Progress Report: September 1963 (open access)

Gas-Cooled Reactor Project Semiannual Progress Report: September 1963

Report documenting the design and testing progress of the Oak Ridge National Laboratory's Gas-Cooled Reactor Program.
Date: January 29, 1964
Creator: Oak Ridge National Laboratory
System: The UNT Digital Library
Railroad Commission of Texas Oil and Gas Division Annual Report: 1994, Volume 1 (open access)

Railroad Commission of Texas Oil and Gas Division Annual Report: 1994, Volume 1

First part of an annual report of the Texas Railroad Commission's Oil and Gas Division providing background on the industry and the agency's activities, information related to the production of oil and gas, and data regarding production by field.
Date: September 29, 1995
Creator: Railroad Commission of Texas. Oil and Gas Division.
System: The Portal to Texas History
Strong ''Quantum'' Chaos in the Global Ballooning Mode Spectrum of Three-dimensional Plasmas (open access)

Strong ''Quantum'' Chaos in the Global Ballooning Mode Spectrum of Three-dimensional Plasmas

The spectrum of ideal magnetohydrodynamic (MHD) pressure-driven (ballooning) modes in strongly nonaxisymmetric toroidal systems is difficult to analyze numerically owing to the singular nature of ideal MHD caused by lack of an inherent scale length. In this paper, ideal MHD is regularized by using a k-space cutoff, making the ray tracing for the WKB ballooning formalism a chaotic Hamiltonian billiard problem. The minimum width of the toroidal Fourier spectrum needed for resolving toroidally localized ballooning modes with a global eigenvalue code is estimated from the Weyl formula. This phase-space-volume estimation method is applied to ballooning-unstable plasma equilibria in the H-1NF helical axis stellarator and the Large Helical Device (LHD).
Date: November 29, 2000
Creator: Dewar, R. L.; Cuthbert, P. & Ball, R.
System: The UNT Digital Library
Select Thermal and Physical Property Data for Lead Carbonate (open access)

Select Thermal and Physical Property Data for Lead Carbonate

None
Date: December 29, 2005
Creator: DAUGHERTY, WILLIAM
System: The UNT Digital Library
The Future Direction of U.S. Foreign Party: A Compilation of Views and Opinions (open access)

The Future Direction of U.S. Foreign Party: A Compilation of Views and Opinions

This report documents articles critiquing the United States' foreign policy. The critiques focus on reexamining the major tenants of foreign policy, defining foreign policy as it relates to other countries, and interdependence.
Date: April 29, 1976
Creator: Goodman, Margaret G.
System: The UNT Digital Library
Free-Flight Investigation of Control Effectiveness of Full-Span 0.2-Chord Plain Ailerons at High Subsonic, Transonic, and Supersonic Speeds to Determine Some Effects of Section Thickness and Wing Sweepback (open access)

Free-Flight Investigation of Control Effectiveness of Full-Span 0.2-Chord Plain Ailerons at High Subsonic, Transonic, and Supersonic Speeds to Determine Some Effects of Section Thickness and Wing Sweepback

Report discusses the development and testing of a rocket-propelled test vehicle to investigate aerodynamic control effectiveness at high subsonic, transonic, and supersonic speeds. Modifications to the section thickness and wing sweepback to improve performance are also described. A description of the vehicle, instrumentation, accuracy, and evaluation of testing results is included.
Date: May 29, 1947
Creator: Sandahl, Carl A. & Marino, Alfred A.
System: The UNT Digital Library
Deactivation by Carbon of Iron Catalysts for Indirect Liquefaction (open access)

Deactivation by Carbon of Iron Catalysts for Indirect Liquefaction

This report describes recent progress in a fundamental, three-year investigation of carbon formation and its effects on the activity and selectivity of promoted iron catalysts for synthesis, the objectives of which are: determine rates and mechanisms of carbon deactivation of unsupported Fe and Fe/K catalysts during CO hydrogenation over a range of CO concentrations, CO:H{sub 2} ratios, and temperatures; model the rates of deactivation of the same catalysts in fixed-bed reactors. During the fourteenth quarter design of software for a computer-automated reactor system to be used in the kinetic and deactivation studies was continued. Further progress was made toward the completion of the control language, control routines, and software for operating this system. Progress was also made towards testing of the system hardware and software. 47 refs.
Date: October 29, 1990
Creator: Bartholomew, C. H.
System: The UNT Digital Library