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X-ray scattering studies of non-equilibrium ordering processes. Progress report, November 1, 1989--October 31, 1992

Description: This report summarizes the major results obtained under US DOE Grant Number FG05-90ER45280 from the dates November 1, 1989 through October 31, 1992 inclusive. The principal work includes x-ray scattering studies of phase transition kinetics in binary alloy order-disorder transitions, block co-polymer crystallization, and charge density wave solids under applied electric fields, and studies of magnetic excitations in low dimensional quantum systems.
Date: June 1, 1992
Creator: Nagler, S. E.
Partner: UNT Libraries Government Documents Department

Experimental efforts and results in finding new heavy scintillators

Description: New heavy scintillators are being discovered with increasing frequency. In recent years NaI(Tl) (with its high light output and energy resolution) has been joined by BGO (with its high stopping power), BaF{sub 2} (with its excellent timing resolution), and CeF{sub 3} (with its speed and short Moliere radius). More than 10 potentially useful scintillators have been under development in the past five years, such as PbSO{sub 4} and Lu{sub 2}SiO{sub 5}(Ce). We tabulate the characteristics of these and other scintillators, including wavelength, luminous efficiency, decay time, and initial intensity. We describe a search strategy and the prospects for finding the ``ideal`` heavy scintillator, which would combine the light output of NaI(Tl) and CsI(Tl), the stopping power of BGO, and the speed of BaF{sub 2} and ZnO(Ga).
Date: September 1, 1992
Creator: Derenzo, S. E. & Moses, W. W.
Partner: UNT Libraries Government Documents Department

Exotic atoms and leptonic conservations. Technical progress report, February 1, 1990--January 31, 1991

Description: The major 1989 efforts have been on two aspects of experiments at TRIUMF. One effort was production of muonic hydrogen and muonic deuterium into a vacuum. The study includes rates relevant to muon-catalyzed fusion, and if there are found an adequate number of muons in the 2-S state, then precision energies will be measured. The second effort was to develop plans for kaonic atoms at the kaon factory. In addition, analyses from the experiments with pionic atoms at LAMPF were completed.
Date: December 31, 1991
Creator: Kunselman, R.
Partner: UNT Libraries Government Documents Department

Neutron scatter studies of chromatin structures related to functions. Technical progress report, November 1, 1991--May 15, 1992

Description: We have made considerable progress in chromatin reconstitution with very lysine rich histone H1/H5 and in understanding the dynamics of nucleosomes. A ferromagnetic fluid was developed to align biological molecules for structural studies using small-angle-neutron-scattering. We have also identified and characterized in intrinsically bent DNA region flaking the RNA polymerase I binding site of the ribosomal RNA gene in Physarum Polycephalum. Finally projects in progress are in the areas of studying the interactions of histone H4 amino-terminus peptide 1-23 and acetylated 1-23 peptide with DNA using thermal denaturation; study of GGAAT repeats found in human centromeres using high resolution Nuclear Magnetic Resonance and nuclease sentivity assay; and the role of histones and other sperm specific proteins with sperm chromatin.
Date: June 1, 1992
Creator: Bradbury, E. M.
Partner: UNT Libraries Government Documents Department

Wear-mechanism modelling. Final report

Description: Goals of the program are to calculate the surface temperatures in dry sliding, develop a soft wear tester for ceramics, survey the wear mechanisms in brittle solids, and couple the temperature calculations with models to give wear maps for brittle solids. (DLC)
Date: March 1, 1993
Creator: Ashby, M. F.
Partner: UNT Libraries Government Documents Department

Ultrafast readout of scintillating fibers using upgraded position-sensitive photomultipliers. Progress report, FY 1993

Description: Experimental results obtained with commercially available position-sensitive photomultipliers (PSPM) coupled with 0.5 mm diameter scintillating fiber arrays show some promising performances such as space resolution better than 200 {mu}m and time resolution {approx} 1.5 ns with a detection efficiency higher than 90%. Major progress has also been recently achieved with an upgrade of a PSPM based on new grid dynode structures. Two-track spatial resolution has been studied using the upgraded PSPM. Initial studies demonstrate that two tracks separated by a minimum distance of 3 mm are resolved.
Date: January 1, 1994
Creator: Onel, Y.
Partner: UNT Libraries Government Documents Department

Analysis of organics in 643-G groundwaters by GC/MS

Description: Twenty-three of the 63 monitoring wells in the 643-G burial ground consistently contain measurable (> 1 ppm) amounts of total organic carbon, TOC. Of these 23 wells, 10 that contain elevated (2--400 ppm) TOC were chosen for in-depth analysis of semivolatile organics by gas chromatography/mass spectrometry, GC/MS. A well located near the site of previous decontamination operations was also chosen for analysis. About 40% of the organic compounds detected in these well waters have been identified. Many of these compounds are indicative of liquid scintillation wastes, spent solvent wastes, and solvent degradation products. Four priority pollutants were present at low levels. Some of the organics identified are probably degradation products from humic substances. Organic compounds of unknown origin are also present. No strong chelators capable of increasing radionuclide mobility have been identified. Preliminary dialysis work indicates that up to 30--40% of the TOC may be present as nonvolatile humic substances that cannot be analyzed by GC/MS.
Date: September 26, 1985
Creator: Hoeffner, S. L.; Denham, E. L. & Oblath, S. B.
Partner: UNT Libraries Government Documents Department

Particle reflection and TFTR neutral beam diagnostics

Description: Determination of two critical neutral beam parameters, power and divergence, are affected by the reflection of a fraction of the incident energy from the surface of the measuring calorimeter. On the TFTR Neutral Beam Test Stand, greater than 30% of the incident power directed at the target chamber calorimeter was unaccounted for. Most of this loss is believed due to reflection from the surface of the flat calorimeter, which was struck at a near grazing incidence (12{degrees}). Beamline calorimeters, of a ``V``-shape design, while retaining the beam power, also suffer from reflection effects. Reflection, in this latter case, artificially peaks the power toward the apex of the ``V``, complicating the fitting technique, and increasing the power density on axis by 10 to 20%; an effect of import to future beamline designers. Agreement is found between measured and expected divergence values, even with 24% of the incident energy reflected.
Date: April 1, 1992
Creator: Kamperschroer, J. H.; Grisham, L. R.; Kugel, H. W.; O`Connor, T. E.; Newman, R. A.; Stevenson, T. N. et al.
Partner: UNT Libraries Government Documents Department

The history of NATO TNF policy: The role of studies, analysis and exercises conference proceedings. Volume 3: Papers by Gen. Robert C. Richardson III (Ret.)

Description: This conference was organized to study and analyze the role of simulation, analysis, modeling, and exercises in the history of NATO policy. The premise was not that the results of past studies will apply to future policy, but rather that understanding what influenced the decision process-and how-would be of value. The structure of the conference was built around discussion panels. The panels were augmented by a series of papers and presentations focusing on particular TNF events, issues, studies, or exercises. The conference proceedings consist of three volumes. Volume 1 contains the conference introduction, agenda, biographical sketches of principal participants, and analytical summary of the presentations and discussion panels. Volume 2 contains a short introduction and the papers and presentations from the conference. This volume contains selected papers by Brig. Gen. Robert C. Richardson III (Ret.).
Date: February 1, 1994
Creator: Rinne, R. L.
Partner: UNT Libraries Government Documents Department

[Tonoplast transport and salt tolerance in plants]. Progress report

Description: We have showed that the tonoplast V-ATPase could be specifically inhibited by antisense DNA to the catalytic (A) subunit; that cell expansion was inhibited in carrot transformants deficient in the enzyme and have provided evidence for at least two different isoforms of the A subunit which are Golgi- and tonoplast-specific. These findings prompted a search for sequences of the isoforms of the A subunit in carrot. We have cloned and sequenced 1.0--1.5 kb fragments of three different genes for the catalytic subunit, the fragments differ greatly in their introns, but have nearly identical exons. We are using PCR to amplify and subclone carrot seedling cDNA. Thus far two bands have been amplified and are currently being subcloned for sequencing.
Date: April 1, 1993
Creator: Taiz, L.
Partner: UNT Libraries Government Documents Department

Transient flows and pressure waves in pipes

Description: Transient laminar flows and pressure-wave propagations in pipes connected with components, commonly known as water hammer, are analyzed. The system studied consists of a constant-pressure vessel, a uniform circular pipe, a valve between them, and a receiver vessel. A pressure-wave equation and a linearized velocity equation are derived from the equations of mass and momentum conservation. Waveform distortion due to viscous dissipation and pipe-wall elastic expansion is characterized by a dimensionless transmission number, K. The coefficients of the damping of the pressure waves were found to be related to the roots of the Bessel function J{sub 0}. An exact solution of the pressure-wave equation was obtained numerically. The relationship between the distortion of a traveling wave and the transmission number K was studied. The problem is also calculated with a general-purpose computer code, COMMIX, which solves the exact mass conservation equation and Navier-Stokes equations. The COMMIX calculational results agreed well with the analytical solutions.
Date: June 1, 1994
Creator: Wang, X. Q.; Sun, J. G. & Sha, W. T.
Partner: UNT Libraries Government Documents Department

Hanford Laboratories monthly activities report, April, 1963

Description: This is the monthly report for the Hanford Laboratories Operation, April, 1963. Reactor fuels, chemistry, dosimetry, separation processes, reactor technology financial activities, biology operation, physics and instrumentation research, employee relations, applied mathematics operation, programming, and radiation protection operation discussed.
Date: May 15, 1963
Partner: UNT Libraries Government Documents Department

Modeling and database for melt-water interfacial heat transfer

Description: A mechanistic model is developed to predict the transition superficial gas velocity between bulk cooldown and crust-limited heat transfer regimes in a sparged molten pool with a coolant overlayer. The model has direct applications in the analysis of ex-vessel severe accidents, where molten corium interacts with concrete, thereby producing sparging concrete decomposition gases. The analysis approach embodies thermal, mechanical, and hydrodynamic aspects associated with incipient crust formation at the melt/coolant interface. The model is validated against experiment data obtained with water (melt) and liquid nitrogen (coolant) simulants. Predictions are then made for the critical gas velocity at which crust formation will occur for core material interacting with concrete in the presence of water.
Date: April 1, 1992
Creator: Farmer, M. T.; Spencer, B. W.; Schneider, J. P.; Bonomo, B. & Theofanous, G.
Partner: UNT Libraries Government Documents Department

Status and integration of the gas generation studies performed for the Hydrogen Safety Program. FY-1992 Annual report

Description: Waste in Tank 241-SY-101 on the Hanford Site generates and periodically releases hydrogen, nitrous oxide, and nitrogen gases. Studies have been conducted at several laboratories to determine the chemical mechanisms for the gas generation and release. Results from these studies are presented and integrated in an attempt to describe current understanding of the physical properties of the waste and the mechanisms of gas generation and retention. Existing tank data are consistent with the interpretation that gases are uniformly generated in the tank, released continuously from the convecting layer, and stored in the nonconvecting layer. Tank temperature measurements suggest that the waste consists of ``gobs`` of material that reach neutral buoyancy at different times. The activation energy of the rate limiting step of the gas generating process was calculated to be about 7 kJ/mol but measured in the laboratory at 80 to 100 kJ/mol. Based on observed temperature changes in the tank the activation energy is probably not higher than about 20 kJ/mol. Several simulated waste compositions have been devised for use in laboratory studies in the place of actual waste from Tank 241-SY-101. Data from these studies can be used to predict how the actual waste might behave when heated or diluted. Density evaluations do not confirm that heating waste at the bottom of the tank would induce circulation within the waste; however, heating may release gas bubbles by dissolving the solids to which the bubbles adhere. Gas generation studies on simulated wastes indicated that nitrous oxide and hydrogen yields are not particularly coupled. Solubility studies of nitrous oxide, the most soluble of the principal gaseous products, indicate it is unlikely that dissolved gases contribute substantially to the quantity of gas released during periodic events.
Date: February 1, 1993
Creator: Pederson, L. R. & Strachan, D. M.
Partner: UNT Libraries Government Documents Department

Palladium on kieselguhr

Description: Palladium supported in kieselguhr (Pd/K) is a candidate material for processing of hydrogen isotopes at Savannah River Laboratory (SRL) and Savannah River Plant (SRP). Kieselguhr is a porous, sedimentary rock composed of silicified skeletal remains of single-celled aquatic plants called diatoms. SRL has developed a process for deposition of palladium on kieselguhr particles using immersion in an ammonical palladium chloride solution followed by heating in hydrogen to decompose the chloride to metallic palladium. The goal is to produce Pd/K particles with less than 250 ppm chlorine.
Date: January 11, 1988
Creator: Mosley, W. C.
Partner: UNT Libraries Government Documents Department

Pressurized fluidized-bed hydroretorting of Eastern oil shales. Progress report, July--September 1988

Description: The Devonian oil shales of the Eastern United States are a significant domestic energy resource. The overall objective of the 3-year program, is to perform the research necessary to develop the pressurized fluidized-bed hydroretorting (PFH) process for producing oil from Eastern oil shales. The program also incorporates research on technologies in areas such as raw shale preparation, beneficiation, product separation, and waste disposal that have the potential of improving the economics and/or environmental acceptability of recovering oil from oil shales using the PFH process. The program is divided into the following eight tasks: Task 1, PFH Scoping Studies; Task 2, PFH Optimization Tests; Task 3, Testing of Process Improvement Concepts; Task 4, Beneficiation Research; Task 5, Operation of PFH on Beneficiated Shale; Task 6, Environmental Data and Mitigation Analyses; Task 7, Sample Procurement, Preparation, and Characterization; Task 8, Project Management and Reporting. In order to accomplish all the program objectives, the Institute of Gas Technology, the prime contractor, is working with six other institutions; the University of Alabama/Mineral Resources Institute, Illinois Institute of Technology, the University of Michigan, Ohio State University, Tennessee Technological University and the University of Pittsburgh. This report presents the work performed during the fourth program quarter from July 1 through September 30, 1988.
Date: December 1, 1988
Creator: Punwani, D. V.; Lau, F. S.; Knowlton, T. M.; Akin, C.; Roberts, M. J.; Findlay, J. G. et al.
Partner: UNT Libraries Government Documents Department

Environmental release summary (ERS) database CY 1997

Description: This report discusses the Environmental Release Summary (ERS) database. The current needs of the Effluent and Environmental database is continually modified to fulfill monitoring (EEM) program (managed by Waste Management Federal Services of Hanford, Incorporated, Air and Water Services Organization). Changes are made to accurately calculate current releases, to affect how past releases are calculated. This document serves as a snap-shot of the database and software for the CY-1997 data and releases. This document contains all of the relevant data for calculating radioactive-airborne and liquid effluent. The ERS database is the official repository for the CY-1997 ERS release reports and the settings used to generate those reports. As part of the Tri-Party Agreement, FDH is committed to provide a hard copy of the ERS database for Washington State Department of Ecology, upon request. This document also serves as that hard copy for the last complete calendar year.
Date: July 1, 1998
Creator: Gleckler, B. P.
Partner: UNT Libraries Government Documents Department

Development of an inert ceramic anode to reduce energy consumption in magnesium production. Technical progress report, January 1, 1992--December 31, 1992

Description: Raw material (titania doped with Ta{sub 2}O{sub 5})selection, development of clip casting as greenware forming method, and sintering studies have been completed. External side and shape of the ceramic portion of the anode has been set. Wall thickness is controlled by slip and casting time. Sintered tubes have been made with wall thicknesses 2.5-5.0 mm; optimum thickness will be determined. Modeling studies show that the conceptual design should survive the applied stresses. Results of strength testing of slip cast and sintered titania-Ta{sub 2}O{sub 5} exceed values used in the model. Materials causing bonding of the core`s metal component and the ceramic particulate filler and the ceramic shell need further study. 6 refs, 8 figs, tabs.
Date: December 31, 1992
Partner: UNT Libraries Government Documents Department

Modeling node bandwidth limits and their effects on vector combining algorithms

Description: Each node in a message-passing multicomputer typically has several communication links. However, the maximum aggregate communication speed of a node is often less than the sum of its individual link speeds. Such computers are called node bandwidth limited (NBL). The NBL constraint is important when choosing algorithms because it can change the relative performance of different algorithms that accomplish the same task. This paper introduces a model of communication performance for NBL computers and uses the model to analyze the overall performance of three algorithms for vector combining (global sum) on the Intel Touchstone DELTA computer. Each of the three algorithms is found to be at least 33% faster than the other two for some combinations of machine size and vector length. The NBL constraint is shown to significantly affect the conditions under which each algorithm is fastest.
Date: January 13, 1992
Creator: Littlefield, R. J.
Partner: UNT Libraries Government Documents Department

Tritium production using highly enriched fuel

Description: Preliminary studies utilizing the MOFDA code have been made for tritium production at the K reactors using 33 and 35 grams per foot oralloy (93.5% U-235) in aluminum in conjunction with standard K5N and K5E fuel elements, respectively. For this report, it was assumed that all tritium would be produced in discrete charges of LiAl target elements. It is intended that the study will be extended at some later time to include LiAl splines. The analysis includes the effect of coolant loss on reactivity for hot-or-cold and green-or-exposed conditions for several oralloy loading fractions.
Date: December 18, 1967
Creator: Miller, R. L.
Partner: UNT Libraries Government Documents Department

Interim storage of radioactive xenon and krypton gas

Description: This document contains information on the planning of underwater storage of gas cylinders containing radioactive xenon and krypton gases. The 221-U Canyon Pool Cells 1,2, and 4 appear to be the most promising facilities. The proposed modifications for storing these cylinders underwater include mild steel liners, sealed steel covers, and racks to support the cylinders.
Date: January 14, 1971
Creator: Corlew, R. P.
Partner: UNT Libraries Government Documents Department

Compositions and chemical bonding in ceramics by quantitative electron energy-loss spectrometry

Description: Quantitative electron energy-loss spectrometry was applied to a range of ceramic materials at a spatial resolution of <5 nm. Analysis of Fe L{sub 23} white lines indicated a low-spin state with a charge transfer of {approximately}1.5 electrons/atom onto the Fe atoms implanted into (amorphized) silicon carbide. Gradients of 2 to 5% in the Co:O stoichiometry were measured across 100-nm-thick Co{sub 3}O{sub 4} layers in an oxidized directionally solidified CoO-ZrO{sub 2} eutectic, with the highest O levels near the ZrO{sub 2}. The energy-loss near-edge structures were dramatically different for the two cobalt oxides; those for CO{sub 3}O{sub 4} have been incorrectly ascribed to CoO in the published literature. Kinetically stabilized solid solubility occurred in an AlN-SiC film grown by low-temperature molecular beam epitaxy (MBE) on {alpha}(6H)-SiC, and no detectable interdiffusion occurred in couples of MBE-grown AlN on SiC following annealing at up to 1750C. In diffusion couples of polycrystalline AlN on SiC, interfacial 8H sialon (aluminum oxy-nitride) and pockets of Si{sub 3}N{sub 4}-rich {beta}{prime} sialon in the SiC were detected.
Date: December 31, 1993
Creator: Bentley, J.; Horton, L. L.; McHargue, C. J.; McKernan, S.; Carter, C. B.; Revcolevschi, A. et al.
Partner: UNT Libraries Government Documents Department