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Cross Sections for X-Ray Photoelectron-Induced Desorption of Hydrogen Ions From Metal Surfaces (open access)

Cross Sections for X-Ray Photoelectron-Induced Desorption of Hydrogen Ions From Metal Surfaces

We have measured the cross sections for x-ray photoelectron-induced desorption of hydrogen ions from beryllium, carbon, aluminum, tantalum, and gold surfaces. This report describes the results of the cross-section measurements, and discusses a time-of-flight technique that allows the determination of ionic-desorption cross sections as small as 10/sup -25/ cm/sup 2/ per photoelectron. 19 refs., 7 figs.
Date: September 20, 1985
Creator: Kinney, J. H.; Siekhaus, W. J. & Anderson, R. A.
Object Type: Report
System: The UNT Digital Library
Computed and experimental interactions between eddy structure and dispersed particles in developing free shear layers (open access)

Computed and experimental interactions between eddy structure and dispersed particles in developing free shear layers

We are investigating the interactive process between turbulent flow and dispersed phase particles. We are focusing on the mechanisms that appear to result in a reduction of local turbulent intensity and a corresponding reduction in wall heat transfer and subsequent wall erosion in turbulent solid propellant combustion flow. We apply computational simulations and physical experiments specialized to a developing free shear layer over a rearward facing step and over a parallel splitter plate. The flow configuration evolves in a two-dimensional, steady, combustion and non-combustion turbulent free shear mixing region, with and without particle additives. The computational simulations combine three basic components: gas phase Navier-Stokes solutions, Lagrange particle field solutions and a Monte Carlo technique for the random encounters, forces and accelerations between the two fields. We concentrate here on relatively large sized additive particles (of the order of tens of microns to 100 microns mean diameter). We examine their apparent influence in breaking up the larger, energy bearing eddy structures into smaller structures which are more readily dissipated.
Date: May 20, 1982
Creator: Buckingham, A. C.; Siekhaus, W. J.; Keller, J. O.; Ellzey, J.; Hubbard, G. & Daily, J. W.
Object Type: Article
System: The UNT Digital Library
Exact calculations of nuclear-recoil energies from prompt gamma decays resulting from neutron capture (open access)

Exact calculations of nuclear-recoil energies from prompt gamma decays resulting from neutron capture

The results of an accurate determination of the recoil spectrum from (n, ..gamma..) reactions in molybdenum are presented. The recoil spectrum has been calculated from nuclear level structure data and measured branching ratios. Angular correlations between successive gammas have been accounted for using the standard theoretical techniques of Racah algebra and the density matrix formalism.
Date: July 20, 1981
Creator: Kinney, J.H.
Object Type: Report
System: The UNT Digital Library
Facile reaction/extraction of coal with supercritical fluids. Quarterly technical progress report, January 1-March 31, 1984 (open access)

Facile reaction/extraction of coal with supercritical fluids. Quarterly technical progress report, January 1-March 31, 1984

Arylmethyl phenyl ethers undergo competing reactions when treated with Lewis acids in benzene solvent. Apparently, benzene is insufficiently reactive to compete with intramolecular (intrapolymer) nucleophiles and, consequently, no increase in solubility accompanies the cleavages of ether links upon addition of benzene. When better nucleophiles, naphthalene and phenanthene, are provided, carbonium ions generated from ether cleavages are capped and the product is lower in molecular weight and more soluble. It is worth noting that the naphthalene (k/sub rel/ = 300) is nearly as good a trap as the phenol (k/sub rel/ = 450). Since hydroxylic solvents will level the acid strength of BF/sub 3/ to that of ROBF/sub 3//sup -/H/sup +/ and hydrocarbons would not, the acid-catalyzed bond cleavages necessary for unlinking coal may in fact be faster in BF/sub 3/-arene than in BF/sub 3/-phenol. While we have not yet extended these results to coals, we believe that the combination of a relatively mild Lewis acid catalyst, BF/sub 3/, with a good carbonium ion trap, naphthalene, will allow selective cleavage and capping of aryl alkyl ether bonds. 3 references, 2 figures, 3 tables.
Date: April 20, 1984
Creator: Venier, C. G. & Squires, T. G.
Object Type: Report
System: The UNT Digital Library
MHD compressor---expander conversion system integrated with GCR inside a deployable reflector (open access)

MHD compressor---expander conversion system integrated with GCR inside a deployable reflector

This work originates from the proposal MHD Compressor-Expander Conversion System Integrated with a GCR Inside a Deployable Reflector''. The proposal concerned an innovative concept of nuclear, closed-cycle MHD converter for power generation on space-based systems in the multi-megawatt range. The basic element of this converter is the Power Conversion Unit (PCU) consisting of a gas core reactor directly coupled to an MHD expansion channel. Integrated with the PCU, a deployable reflector provides reactivity control. The working fluid could be either uranium hexafluoride or a mixture of uranium hexafluoride and helium, added to enhance the heat transfer properties. The original Statement of Work, which concerned the whole conversion system, was subsequently redirected and focused on the basic mechanisms of neutronics, reactivity control, ionization and electrical conductivity in the PCU. Furthermore, the study was required to be inherently generic such that the study was required to be inherently generic such that the analysis an results can be applied to various nuclear reactor and/or MHD channel designs''.
Date: April 20, 1989
Creator: Tuninetti, G. (Ansaldo S.p.A., Genoa (Italy). Research Div.); Botta, E.; Criscuolo, C.; Riscossa, P. (Ansaldo S.p.A., Genoa (Italy). Nuclear Div.); Giammanco, F. (Pisa Univ. (Italy). Dipt. di Fisica) & Rosa-Clot, M. (Florence Univ. (Italy). Dipt. di Fisica)
Object Type: Report
System: The UNT Digital Library
Leaching study of PNL 76-68 glass beads using the LLNL continuous-flow method and the PNL-modified IAEA method. Final report (open access)

Leaching study of PNL 76-68 glass beads using the LLNL continuous-flow method and the PNL-modified IAEA method. Final report

Lawrence Livermore National Laboratory (LLNL) has conducted a long-term single-pass continuous-flow (SPCF) leaching test of the glass waste form PNL 76-68. Leaching rates of Np, Pu, and various stable elements were measured at 25/sup 0/ and 75/sup 0/C with three different solutions and three different flow rates. The purposes of the study were: (1) to compare SPCF leaching results with the results of a modified IAEA leach test performed by Pacific Northwest Laboratories (PNL); (2) to establish elemental leach rates and their variation with temperature, flow rate and solution composition; and (3) to gain insight into the leaching mechanisms. The LLNL and PNL leach tests yielded results which appear to agree within experimental uncertainties. The magnitude of the leach rates determined for Np and the glass matrix elements is 10/sup -5/ grams of glass/cm/sup 2/ geometric solid surface area/day. The rates increase with temperature and with solution flow rate, and are similar in brine and distilled water but higher in a bicarbonate solution. Other cations exhibit somewhat different behavior, and Pu in particular yields a much lower apparent leach rate, probably because of sorption or precipitation effects after release from the glass matrix. After the initial few days, most elements …
Date: August 20, 1982
Creator: Buddemeier, R. W.; Coles, D. G.; Mensing, R. W.; Rego, J. & Weed, H. C.
Object Type: Report
System: The UNT Digital Library
Low temperature, sulfur tolerant homogeneous catalysts for the water-gas shift reaction (open access)

Low temperature, sulfur tolerant homogeneous catalysts for the water-gas shift reaction

The purpose of this report is to update and reorganize our recent review on homogeneous catalysis of the water-gas shift reaction (WGSR) based on recent literature publications and patents. This updated version will serve as a means of selecting 10 candidate catalyst systems for use in developing effective, sulfur-tolerant, low temperature WGSR catalysts. This report discusses the variations possible in the basic chemistry associated with WGSR catalytic cycles, including basic, acidic, and neutral conditions. Then individual mechanism for specific WGSR catalyst systems are discussed. Finally, on the basis of the literature reports, a list is presented of candidate catalysts and basic systems we have chosen for study in Task 3.
Date: January 20, 1986
Creator: Laine, R. M.
Object Type: Report
System: The UNT Digital Library
Fusion breeder (open access)

Fusion breeder

The fusion breeder is a fusion reactor designed with special blankets to maximize the transmutation by 14 MeV neutrons of uranium-238 to plutonium or thorium to uranium-233 for use as a fuel for fission reactors. Breeding fissile fuels has not been a goal of the US fusion energy program. This paper suggests it is time for a policy change to make the fusion breeder a goal of the US fusion program and the US nuclear energy program. The purpose of this paper is to suggest this policy change be made and tell why it should be made, and to outline specific research and development goals so that the fusion breeder will be developed in time to meet fissile fuel needs.
Date: April 20, 1982
Creator: Moir, Ralph W.
Object Type: Article
System: The UNT Digital Library
Assessment of the response of spent fuel transports to malevolent acts (open access)

Assessment of the response of spent fuel transports to malevolent acts

This paper describes the results of a program conducted at Sandia National Laboratories (SNL) for the US Department of Energy to provide an experimental data base for more accurately assessing the radiological consequences from a hypothetical sabotage attack on a spent fuel shipping cask. The primary objectives of the program were limited to: (1) evaluating the effectiveness of selected high explosive devices (HED) in breaching full-size spent fuel casks, (2) quantifying and characterizing relevant aerosol properties of the released fuel, and (3) using the resulting experimental data to evaluate the radiological health consequences resulting from a hypothetical sabotage attack on a spent fuel shipping cask in a densely populated area. Subscale and full-scale experiments in conjunction with an analytical modeling study were performed to meet the programmatic objectives. The data from this program indicate that the Urban Studies greatly overestimated the impact of malevolent acts directed at spent fuel casks in urban environs. From that standpoint this work could be the basis of additional regulatory revisions of the NRC physical protection requirements. In a larger sense this work can also be the basis of more credible worst case analyses since it defines the actual result of an event which is …
Date: December 20, 1983
Creator: Sandoval, R.P.
Object Type: Article
System: The UNT Digital Library
Cooling water for SSC experiments: Supplemental Conceptual Design Report (SCDR) (open access)

Cooling water for SSC experiments: Supplemental Conceptual Design Report (SCDR)

This paper discusses the following topics on cooling water design on the superconducting super collider; low conductivity water; industrial cooling water; chilled water systems; and radioactive water systems. (LSP)
Date: October 20, 1989
Creator: Doyle, R.E.
Object Type: Report
System: The UNT Digital Library
Review of single transient oscillographic recorders with gigahertz bandwidth (open access)

Review of single transient oscillographic recorders with gigahertz bandwidth

In laser driven inertial confinement fusion research, at Livermore, we are diagnosing many phenomena that occur in a time frame that exceeds the capabilities of even the most advanced, present day oscillographic recording instruments. Many of the by-products of the interaction between the laser beam and fuel pellet are monitored to determine the specifics of the fusion process. By the use of appropriate detectors, we convert the information contained in the radiated by-products to electrical signals which are recorded on high bandwidth oscillographic recorders. Our present range of recording capabilities for one x-ray diagnostic measurement in use at Livermore is shown. A commonly used configuration consists of an XRD-31 x-ray detector connected to a direct access Tektronix R7912 transient digitizer using 1/2 in. diameter air dielectric coaxial cable. This configuration gives a system fwhm of approximately 335 ps. Our premier configuration, on the other hand, consists of an improved response detector and a French Thomson-CSF TSN-660 oscilloscope with a shorter length of coaxial cable (typically 20 feet). The system fwhm in this case is less than 120 ps which is our fastest oscillographic recording system at the present time.
Date: October 20, 1982
Creator: Campbell, D.E.
Object Type: Article
System: The UNT Digital Library
Electrochemical photovoltaic cells/stabilization and optimization of II-VI semiconductors. First technical progress report, 15 April 1980-30 June 1980 (open access)

Electrochemical photovoltaic cells/stabilization and optimization of II-VI semiconductors. First technical progress report, 15 April 1980-30 June 1980

The overall goal of this program is to provide the basis for designing a practical electrochemical solar cell based on the II-VI compound semiconductors. Emphasis is on developing new electrolyte redox systems and electrode surface modifications which will stabilize the II-VI compounds against photodissolution without seriously degrading the long-term solar response. The bulk electrode material properties are also being optimized to provide the maximum solar conversion efficiency and greatest inherent electrode stability. Factors limiting the short circuit current of the n-CdSe/methanol/ferro-ferricyanide system to 17.5 mA/cm/sup 2/ have been identified. The principal limiting factor is apparently specific adsorption of hexacyanoferrate species on the electrode surface which occurs at higher redox couple concentrations and slows the overall charge transfer process. Ion pairing also occurs, resulting in a low mass transport rate (smaller diffusion coefficients and increased solution viscosity), and probably enhances the degree of specific adsorption. Improvements in the performance of this system will require mitigation of the interactions between the redox species and the electrode surface, e.g., via electrolytes with reduced ion-pairing tendencies or the use of electrode surface films. Photoelectrochemically generated polypyrrole films have been shown to protect CdX photoanodes from dissolution while permitting electron exchange with the electrolyte. Current …
Date: July 20, 1980
Creator: Noufi, R.; Tench, D. & Warren, L.
Object Type: Report
System: The UNT Digital Library
Temporal perspective on acid deposition research (open access)

Temporal perspective on acid deposition research

This statement presented to the Subcommittee on Natural Resources of the US House of Representatives gives a definition of acid rain, presents new data on the regional and temporal nature of the problem, and discusses research needs. (ACR)
Date: February 20, 1980
Creator: Hendrey, George R.
Object Type: Report
System: The UNT Digital Library
Collector sealants and breathing. Final Report, 25 September 1978-31 December 1979 (open access)

Collector sealants and breathing. Final Report, 25 September 1978-31 December 1979

The objectives of this program were: (1) to investigate the pertinent properties of a variety of possible sealants for solar collectors and identify the most promising candidates, and (2) to study the effect of breathing in flat-plate, thermal solar collector units. The study involved two types of sealants, Class PS which includes preformed seals or gaskets and Class SC which includes sealing compounds or caulks. It was the intent of the study to obtain data regarding initial properties of candidate elastomers from manufacturers and from the technical literature and to use those sources to provide data pertaining to endurance of these materials under environmental service conditions. Where necessary, these data were augmented by experimental measurements. Environmental stresses evaluated by these measurements included elevated temperatures, moisture, ultraviolet light, ozone and oxygen, and fungus. The second major area of the work involved a study of the effects of materials used and design on the durability of solar collectors. Factors such as design, fabrication, materials of construction, seals and sealing techniques and absorber plate coatings were observed on actual field units removed from service. Such phenomena as leakage, corrosion and formation of deposits on glazing and absorber plate were noted. An evaluation of …
Date: February 20, 1980
Creator: Mendelsohn, M A; Luck, R M; Yeoman, F A & Navish, Jr, F W
Object Type: Report
System: The UNT Digital Library
The MTX (Microwave Tokamak Experiment) data acquisition system (open access)

The MTX (Microwave Tokamak Experiment) data acquisition system

The diagnostic data from the MTX experiment is acquired and processed by an expandable, distributed, multivendor computer network. The system blends a variety of software into a coordinated, unified, and highly flexible design. Using modular software design techniques, we created a system stressing distributed processing, portability, and transparent data access. In our approach to modularity, we standardized communication interfaces between modules and separated generic tasks from machine and application-specific implementations. For flexible distributed processing, we used modular, portable software and LLNL facility that provides an interprocess communication system (IPCS) in the multivendor network. With transparent data access, any program can access data stored anywhere in the network without knowing the specific location. The computer hardware includes a DEC VAX cluster, HP workstations and HP desktop computers. We are using commercial software in addition to packages from MIT, ORNL, and LLNL. 4 refs., 4 figs.
Date: September 20, 1989
Creator: Butner, D. N.; Drlik, M.; Brown, M. D.; Casper, T. A.; Meyer, W. H. & Moller, J. M.
Object Type: Article
System: The UNT Digital Library
State water rights law and geothermal hydrothermal commercialization in five Pacific Rim states (open access)

State water rights law and geothermal hydrothermal commercialization in five Pacific Rim states

The water rights of the five Pacific states - California, Oregon, Washington, Alaska, and Hawaii - and their possible impacts on geothermal development are discussed. (MHR)
Date: March 20, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Site 300 hazardous-waste-assessment project. Interim report: December 1981. Preliminary site reconnaissance and project work plan (open access)

Site 300 hazardous-waste-assessment project. Interim report: December 1981. Preliminary site reconnaissance and project work plan

This document was prepared to outline the scope and objectives of the Hazardous Waste Assessment Project (HWAP) at Site 300. This project was initiated in October, 1981, to investigate the existing solid waste landfills in an effort to satisfy regulatory guidelines and assess the potential for ground-water contamination. This involves a site-specific investigation (utilizing geology, hydrology, geophysics and geochemistry) with the goal of developing an effective ground-water quality monitoring network. Initial site reconnaissance work has begun and we report the results, to date, of our geologic hydrogeologic studies. All known solid waste disposal locations are underlain by rocks of either the Late Miocene Neroly Formation or the Cierbo Formation, both of which are dominantly sandstones interbedded with shale and claystone. The existence of a regional confined (artesian) aquifer, as well as a regional water-table aquifer is postulated for Site 300. Preliminary analysis has led to an understanding of directions and depths of regional ground-water flow.
Date: January 20, 1982
Creator: Raber, E.; Helm, D.; Carpenter, D.; Peifer, D. & Sweeney, J.
Object Type: Report
System: The UNT Digital Library
Automatic voltage-imbalance detector (open access)

Automatic voltage-imbalance detector

A device is described for indicating and preventing damage to voltage cells such as galvanic cells and fuel cells connected in series by detecting sequential voltages and comparing these voltages to adjacent voltage cells. The device is implemented by using operational amplifiers and switching circuitry is provided by transistors. The device can be utilized in battery powered electric vehicles to prevent galvanic cell damage and also in series connected fuel cells to prevent fuel cell damage.
Date: May 20, 1981
Creator: Bobbett, R. E.; McCormick, J. B. & Kerwin, W. J.
Object Type: Patent
System: The UNT Digital Library
Selective emitter. Task II topical report for radiative-cooling materials (open access)

Selective emitter. Task II topical report for radiative-cooling materials

The theoretical basis of the selective emitter is that, if a material emits only in the 8-13 micron interval, it will absorb only in the same interval. After a survey of several candidate materials, the silicon oxynitride system was found to have better optical properties than previously used materials as well as economic feasibility, and efforts to acquire a sample are described. Other promising materials are described: polyvinylidene fluoride (Tedlar), silicon monoxide, silicon dioxide, and silicon nitride. (LEW)
Date: September 20, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Monopole search using an accelerator detector (open access)

Monopole search using an accelerator detector

A neutrino detector at the Brookhaven AGS has been used to investigate the feasibility of using an already constructed apparatus for GUT monopole searches. A flux limit (90%CL) of 5.2 x 10/sup -12/ cm/sup -2/ sec/sup -1/ str/sup -1/ was found. The limitations of such an approach are discussed.
Date: December 20, 1983
Creator: Ahrenes, L.A.; Aronson, S.H.; Connolly, P.L.; Erickson, T.E.; Gibbard, B.G.; Montag, M. et al.
Object Type: Article
System: The UNT Digital Library
Fusion product deposition and energy balance (open access)

Fusion product deposition and energy balance

Extensive Monte-Carlo calculations were performed of alpha-particle deposition in the Hill's Vortex configuration, as reported in D.E. Driemeyer's Ph.D. Thesis (University of Illinois, 1980). This has generally been done including a cold plasma density, n/sub c/, on the open field lines, with n/sub C//T/sub C//sup 3/2/ approx. = n/sub H//T/sub H//sup 3/2/ - i.e. with the slowing down ratio tau/sub H//tau/sub C/ lying between .1 and 10. Since many of the alpha particles spend a significant amount of their time on the open field lines, values of tau/sub H//tau/sub C/ greater than unity lead to significant removal of alpha-particle ash from the closed-field region. Surprisingly, one is able to perform this ash removal and still retain enough energy to raise the reactor Q significantly (or even ignite it).
Date: May 20, 1980
Creator: Condit, W.C. & Driemeyer, D.E.
Object Type: Report
System: The UNT Digital Library
Comparison of the initial ETA gas propagation experiments with theoretical models (open access)

Comparison of the initial ETA gas propagation experiments with theoretical models

This report contains a description of the initial ETA propagation experiments in air at a beam current of 4.5 kA. The beam was observed to propagate at the pressures anticipated on the basis of previous theory and experiment. A comparison of measured net current waveforms with predictions of the PHOENIX code showed good agreement over the pressure range 0.1 to 200 torr. However, the beam was observed to expand with Z at a faster rate than theory predicts. Excessive transverse beam modulation at injection complicated the experiments and limited their comparison with theory.
Date: April 20, 1982
Creator: Chambers, F. W.; Clark, J. C. & Fessenden, T. J.
Object Type: Report
System: The UNT Digital Library
Catalogue of monitoring activities at Rocky Flats: 1978, 1979 (open access)

Catalogue of monitoring activities at Rocky Flats: 1978, 1979

A listing of environmental surveillance sampling endeavors for the years 1978 and 1979 is given in which sampling media, i.e., ambient air, stack effluent air, water, and soil are considered. Sampling locations, frequency of sampling, parameters analyzed, and control limits also are given. The objectives of the sampling are considered in defining the program.
Date: June 20, 1980
Creator: Werkema, M. V.
Object Type: Report
System: The UNT Digital Library
Development of marketable solar assisted heat pumps. Phase II. Summary report, technical results (open access)

Development of marketable solar assisted heat pumps. Phase II. Summary report, technical results

A water source heat pump has been designed that is capable of operating over the range from 40 to 110/sup 0/F entering water temperature and has a heating coefficient of performance greater than six in the upper portion of this range. A computerized heat pump balance program was written to allow the performance of either a water-to-water or a water-to-air heat pump to be predicted in either the heating or cooling mode. A detailed program description, flow charts, and sample outputs are appended. The balance program was used to specify components for a high efficiency water-to-water and a high efficiency water-to-air heat pump. Performance predictions for both units in heating and in cooling are included. The water-to-water and water-to-air performance predictions were compared. The water-to-air approach was clearly superior. A detailed design and layout was done for the three solar-assisted water-to-air heat pump. A horizontal configuration was chosen for marketability reasons. The design was made consistent with high quantity production equipment available in our factories and should result in the lowest possible manufacturing cost. A key question to be answered in this project is whether a reciprocating compressor can operate without damage at the high suction pressures characteristic to the …
Date: February 20, 1981
Creator: Hundt, R. & Heard, S.
Object Type: Report
System: The UNT Digital Library