Analysis of electron heat transport in femtosecond laser-plasma interactions with layered solid targets and with thin foils (open access)

Analysis of electron heat transport in femtosecond laser-plasma interactions with layered solid targets and with thin foils

We analyze two types of experiments that enhance our knowledge of the electron heat transport in femtosecond laser produced plasmas. The first involves layered targets and the fall off of substrate signal with increasing overlayer thickness. The experiment uncertainties are too large at present to definitively quantify the heat transport. The second involves the radiative output from thin foils. The behavior of the spectral response to foil thickness implies that our understanding of the transport within the foils is quite good. 12 refs., 11 figs.
Date: January 10, 1991
Creator: Rosen, Mordecai D.
Object Type: Article
System: The UNT Digital Library
Assessment of the safety of US nuclear weapons and related nuclear test requirements: A post-Bush Initiative update (open access)

Assessment of the safety of US nuclear weapons and related nuclear test requirements: A post-Bush Initiative update

The Nuclear Weapons Reduction Initiative announced by President Bush on September 27, 1991, is described herein as set forth in Defense Secretary Cheney`s Nuclear Arsenal Reduction Order issued September 28, 1991. The implications of the Bush Initiative for improved nuclear weapons safety are assessed in response to a request by US Senators Harkin, Kennedy, and Wirth to the Lawrence Livermore National Laboratory that the author prepare such an assessment. The author provides an estimate of the number of nuclear tests needed to accomplish a variety of specified warhead safety upgrades, then uses the results of this estimate to answer three questions posed by the Senators. These questions concern pit reuse and the number of nuclear tests needed for specified safety upgrades of those ballistic missiles not scheduled for retirement, namely the Minuteman III, C4, and D5 missiles.
Date: December 10, 1991
Creator: Kidder, R. E.
Object Type: Report
System: The UNT Digital Library
Benchmark field study of deep neutron penetration (open access)

Benchmark field study of deep neutron penetration

A unique benchmark neutron field has been established at the Lawrence Livermore National Laboratory (LLNL) to study deep penetration neutron transport. At LLNL, a tandem accelerator is used to generate a monoenergetic neutron source that permits investigation of deep neutron penetration under conditions that are virtually ideal to model, namely the transport of mono-energetic neutrons through a single material in a simple geometry. General features of the Lawrence Tandem (LATAN) benchmark field are described with emphasis on neutron source characteristics and room return background. The single material chosen for the first benchmark, LATAN-1, is a steel representative of Light Water Reactor (LWR) Pressure Vessels (PV). Also included is a brief description of the Little Boy replica, a critical reactor assembly designed to mimic the radiation doses from the atomic bomb dropped on Hiroshima, and its us in neutron spectrometry. 18 refs.
Date: June 10, 1991
Creator: Morgan, J. F.; Sale, K. (Lawrence Livermore National Lab., CA (USA) ); Gold, R.; Roberts, J. H. & Preston, C. C. (Metrology Control Corp., Richland, WA (USA) )
Object Type: Article
System: The UNT Digital Library
Capabilities required to conduct the LLNL plutonium mission (open access)

Capabilities required to conduct the LLNL plutonium mission

This report outlines the LLNL plutonium related mission anticipated over the next decade and defines the capabilities required to meet that mission wherever the Plutonium Facility is located. If plutonium work is relocated to a place where the facility is shared, then some capabilities can be commonly used by the sharing parties. However, it is essential that LLNL independently control about 20000 sq ft of net lab space, filled with LLNL controlled equipment, and staffed by LLNL employees. It is estimated that the cost to construct this facility should range from $140M to $200M. Purchase and installation of equipment to replace that already in Bldg 332 along with additional equipment identified as being needed to meet the mission for the next ten to fifteen years, is estimated to cost $118M. About $29M of the equipment could be shared. The Hardened Engineering Test Building (HETB) with its additional 8000 sq ft of unique test capability must also be replaced. The fully equipped replacement cost is estimated to be about $10M. About 40000 sq ft of setup and support space are needed along with office and related facilities for a 130 person resident staff. The setup space is estimated to cost $8M. …
Date: September 10, 1991
Creator: Kass, J.; Bish, W.; Copeland, A.; West, J.; Sack, S. & Myers, B.
Object Type: Report
System: The UNT Digital Library
Chasing the x sub f dependence of J/. Psi. production (open access)

Chasing the x sub f dependence of J/. Psi. production

We discuss the combined effects of hard scattering processes and intrinsic heavy-quark components in the hadron wavefunction on the x{sub f} dependence of J/{psi} production. The A dependence arises from nuclear absorption, comover interactions, shadowing of parton distributions, and intrinsic heavy quarks. 9 refs., 1 fig.
Date: June 10, 1991
Creator: Vogt, R.
Object Type: Article
System: The UNT Digital Library
A compilation of the data on the low-. beta. spools (open access)

A compilation of the data on the low-. beta. spools

Each of the high gradient correction quadrupoles associated with the new low-{beta} lattice is built into a package which contains correction coils similar to the correction coils in the existing Tevatron spool packages. These coils have been measured in Lab 5. The quench currents are measured in a vertical dewar. The only correction element which failed the quench test was TSL003. In that one case the skew dipole coil quenched at 90A, lower than the required current of 100A. The strength of the various coils (the magnetic field B is measured at a radius of 1 in. with 50A in the coil) and the harmonic composition of the magnetic field due to the various coils are measured with the coil warm using a 11Hz signal in the coils. The strength of a coil can be used to compute a transfer constant. The transfer constant is then used to compute the current needed to generate the value of the field in the coil needed for Tevatron operation. Currently, I believe, nominal values of the transfer constants are used, but it would be better if the actual values were available and used.
Date: October 10, 1991
Creator: Gelfand, N.M.
Object Type: Report
System: The UNT Digital Library
A compilation of the data on the low-{beta} spools (open access)

A compilation of the data on the low-{beta} spools

Each of the high gradient correction quadrupoles associated with the new low-{beta} lattice is built into a package which contains correction coils similar to the correction coils in the existing Tevatron spool packages. These coils have been measured in Lab 5. The quench currents are measured in a vertical dewar. The only correction element which failed the quench test was TSL003. In that one case the skew dipole coil quenched at 90A, lower than the required current of 100A. The strength of the various coils (the magnetic field B is measured at a radius of 1 in. with 50A in the coil) and the harmonic composition of the magnetic field due to the various coils are measured with the coil warm using a 11Hz signal in the coils. The strength of a coil can be used to compute a transfer constant. The transfer constant is then used to compute the current needed to generate the value of the field in the coil needed for Tevatron operation. Currently, I believe, nominal values of the transfer constants are used, but it would be better if the actual values were available and used.
Date: October 10, 1991
Creator: Gelfand, N. M.
Object Type: Report
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

Although promoted cobalt and iron catalysts for Fischer-Tropsch (FT) synthesis of gasoline feedstock were first developed more than three decades ago, a major technical problem still limiting the commercial use of these catalysts today is carbon deactivation. 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 FT synthesis, the objectives of which are to: 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; and model the rates of deactivation of the same catalysts in fixed-bed reactors. To accomplish the above objectives, the project is divided into the following tasks: (1) determine the kinetics of reaction and of carbon deactivation during CO hydrogenation on Fe and Fe/K catalysts coated on monolith bodies. (2) Determine the reactivities and types of carbon deposited during reaction on the same catalysts from temperature-programmed-surface-reaction spectroscopy (TPSR) and transmission electron microscopy (TEM). Determine the types of iron carbides formed at various temperatures and H{sub 2}/CO ratios using x-ray diffraction and Moessbauer spectroscopy. (3) Develop mathematical deactivation models which include heat and mass …
Date: January 10, 1991
Creator: Bartholomew, C. H.
Object Type: Report
System: The UNT Digital Library
Design, Analysis, and Spacecraft Integration of RTGs for CRAF and Cassini Missions (open access)

Design, Analysis, and Spacecraft Integration of RTGs for CRAF and Cassini Missions

This report consists of two parts. Part 1 describes the development of novel analytical methods needed to predict the BOM performance and the subsequent performance degradation of the mutually obstructed RTGs for the CRAF and Cassini missions. Part II applies those methods to the two missions, presents the resultant predictions, and discusses their programmatic implications.; The results indicate that JPL's original power demand goals could have been met with two standard GPHS RTGs for each mission. However, JPL subsequently raised both the power demand profile and the duration for both missions, to the point where two standard RTGs could no longer provide the desired power margin. Each mission can be satisfied by adding a third RTG, and in the case of the Cassini mission the use of three RTGs appears to be unavoidable. In the case of the CRAF mission, there appears to be a possibility that modest modifications of the RTGs' design and/or operating scheme and meet the missions' power demand without the addition of a third RTG. The potential saving in cost and schedule pressure prompted Fairchild to undertake a study of various obvious and not-so-obvious stratagems, either singly or in combination, to determine whether they would make …
Date: July 10, 1991
Creator: Schock, Alfred; Or, Chuen T & Noravian, Heros
Object Type: Report
System: The UNT Digital Library
Effect of Melting on Target Performance (open access)

Effect of Melting on Target Performance

The brightness of the antiproton source increases as the proton beam spot size on the target is reduced. The RMS beam spot size may be reduced to below {sigma}{sub b} = 0.1 mm, before competing sources of emittance limit the achievable yield. At the same time, the density of energy deposition increases rapidly as the radius is reduced. Thus operation of the target at the highest yields subjects the target to very high peak energy deposition E{sub m}. Fits to the Monte-Carlo calculations of target yield and energy deposition from Ref. 1 are plotted in Figure 1. Experience has shown little or no sign of damage in copper targets up to about 500 J/g. If, as the energy density is increased, rupture of the copper target due to overpressure or shock-induced tensile stress does not occur, the ultimate brightness of the target will be limited by melting of the target material and consequent density depletion. This outcome was anticipated early in development of the antiproton source [Ref. 2]. The current memo addresses the melting problem with the goal of predicting the practical limitations of the target as the proton intensity is increased to 5 x 10{sup 12} protons per pulse. …
Date: September 10, 1991
Creator: Bieniosek, F.M.
Object Type: Report
System: The UNT Digital Library
Electron energies in metals (open access)

Electron energies in metals

The modern era of electron-electron interactions began a decade ago. Plummer's group initiated a program of using angular resolved photoemission to examine the band structure of the simple metals. Beginning with aluminum, and carrying on to sodium and potassium, they always found that the occupied energy bands were much narrower than expected. For example, the compressed energy bands for metallic potassium suggest a band effective mass of m* = 1.33m{sub e}. This should be compared to the band mass found from optical conductivity m*/m{sub e} = 1.01 {plus minus} 0.01. The discrepancy between these results is startling. It was this great difference which started my group doing calculations. Our program was two-fold. On one hand, we reanalyzed the experimental data, in order to see if Plummer's result was an experimental artifact. On the other hand, we completely redid the electron-electron self-energy calculations for simple metals, using the most modern choices of local-field corrections and vertex corrections. Our results will be reported in these lectures. They can be summarized as following: Our calculations give the same effective masses as the older calculations, so the theory is relatively unchanged; Our analysis of the experiments suggests that the recent measurements of band narrowing …
Date: July 10, 1991
Creator: Mahan, G.D. (Oak Ridge National Lab., TN (United States) Tennessee Univ., Knoxville, TN (United States). Dept. of Physics and Astronomy)
Object Type: Article
System: The UNT Digital Library
Estimating market penetration of new district heating and cooling systems using a combination of economic cost and diffusion models (open access)

Estimating market penetration of new district heating and cooling systems using a combination of economic cost and diffusion models

The economic-cost model and the diffusion model are among the many market-penetration forecasting approaches that are available. These approaches have been used separately in many applications. In this paper, the authors briefly review these two approaches and then describe a methodology for forecasting market penetration using both approaches sequentially. This methodology is illustrated with the example of market-penetration forecasting of new district heating and cooling (DHC) systems in the Argonne DHC Market Penetration Model, which was developed and used over the period 1979--1983. This paper discusses how this combination approach, which incorporates the strengths of the economic-cost and diffusion models, has been superior to any one approach for market forecasts of DHC systems. Also discussed are the required modifications for revising and updating the model in order to generate new market-penetration forecasts for DHC systems. These modifications are required as a result of changes in DHC engineering, economic, and market data from 1983 to 1990. 13 refs., 5 figs., 2 tabs.
Date: May 10, 1991
Creator: Teotia, Arvind P. S. & Karvelas, Dimitrios E.
Object Type: Article
System: The UNT Digital Library
Fuel oil and kerosene sales, 1990 (open access)

Fuel oil and kerosene sales, 1990

Sales data is presented for kerosene and fuel oils. This is the second year that the survey data have appeared in a separate publication. Prior to the 1989 report, the statistics appeared in the Petroleum Marketing Annual (PMA) for reference year 1988 and the Petroleum Marketing Monthly (PMM) for reference years 1984 through 1987. 4 figs., 24 tabs.
Date: October 10, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The future of defense and technology (open access)

The future of defense and technology

This document provides an insight into the future of national defense and the impacts of utilizing technology for improved defensive postures. (FI)
Date: January 10, 1991
Creator: Teller, E.
Object Type: Article
System: The UNT Digital Library
Historical river flow rates for dose calculations (open access)

Historical river flow rates for dose calculations

Annual average river flow rates are required input to the LADTAP Computer Code for calculating offsite doses from liquid releases of radioactive materials to the Savannah River. The source of information on annual river flow rates used in dose calculations varies, depending on whether calculations are for retrospective releases or prospective releases. Examples of these types of releases are: Retrospective - releases from routine operations (annual environmental reports) and short term release incidents that have occurred. Prospective - releases that might be expected in the future from routine or abnormal operation of existing or new facilities (EIS`s, EID`S, SAR`S, etc.). This memorandum provides historical flow rates at the downstream gauging station at Highway 301 for use in retrospective dose calculations and derives flow rate data for the Beaufort-Jasper and Port Wentworth water treatment plants.
Date: June 10, 1991
Creator: Carlton, W. H.
Object Type: Report
System: The UNT Digital Library
Institute of geophysics and planetary physics (open access)

Institute of geophysics and planetary physics

This report contains brief discussions on topics of high-pressure sciences, astrophysics, and geosciences. (LSP)
Date: May 10, 1991
Creator: Ryerson, F. & Budwine, C. M.
Object Type: Report
System: The UNT Digital Library
Integrated dry NO sub x /SO sub 2 emissions control system (open access)

Integrated dry NO sub x /SO sub 2 emissions control system

This project's goal is to demonstrate the removal up to 70% of the NO{sub x} and 70% of the SO{sub 2} emissions from coal fired utility boilers. It will establish an alternative emissions control technology integrating a combination of several processes, while minimizing capital expenditures and limiting waste production to dry solids that are handled with convention ash removal equipment. These processes include low-NO{sub x} burners and urea injection for NO{sub x} control, sodium- or calcium-based sorbent injection for SO{sub 2} control, and flue gas humidification to enhance the reactivity of the SO{sub 2} control compound.
Date: September 10, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Integrated dry NO{sub x}/SO{sub 2} emissions control system. Quarterly report No. 1, January 1--March 31, 1991 (open access)

Integrated dry NO{sub x}/SO{sub 2} emissions control system. Quarterly report No. 1, January 1--March 31, 1991

This project`s goal is to demonstrate the removal up to 70% of the NO{sub x} and 70% of the SO{sub 2} emissions from coal fired utility boilers. It will establish an alternative emissions control technology integrating a combination of several processes, while minimizing capital expenditures and limiting waste production to dry solids that are handled with convention ash removal equipment. These processes include low-NO{sub x} burners and urea injection for NO{sub x} control, sodium- or calcium-based sorbent injection for SO{sub 2} control, and flue gas humidification to enhance the reactivity of the SO{sub 2} control compound.
Date: September 10, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Novel macrocyclic carriers for proton-coupled liquid membrane transport (open access)

Novel macrocyclic carriers for proton-coupled liquid membrane transport

The objective of our research program is to elucidate the chemical principles which are responsible for the cation selectivity and permeability of liquid membranes containing macrocyclic carriers. Several new macrocyclic carriers were synthesized during the last three year period, including selenium-containing macrocycles, new crown-4 structures, and several new crown structures containing nitrogen based heterocycles as substituents in the principal macrocyclic ring. The cation binding properties of these macrocycles were investigated by potentiometric titration, calorimetric titration, solvent extraction, and NMR techniques. In addition, hydrophobic macrocycles were incorporated into dual hollow fiber membrane systems to investigate their membrane performance, especially in the proton-coupled transport mode. It was found that the dual hollow fiber system maintains the cation selectivity and permeability of supported liquid membranes, while enhancing membrane stability. The diffusion limited transport model was expanded to account for membrane solvent effects. Furthermore, Eu{sup 2+} transport was found to be similar to that of strontium and much higher than that of the lanthanides, in supported liquid membrane systems.
Date: June 10, 1991
Creator: Lamb, J.D.
Object Type: Report
System: The UNT Digital Library
Novel macrocyclic carriers for proton-coupled liquid membrane transport. Progress report, 1 December 1988--31 May 1991 (open access)

Novel macrocyclic carriers for proton-coupled liquid membrane transport. Progress report, 1 December 1988--31 May 1991

The objective of our research program is to elucidate the chemical principles which are responsible for the cation selectivity and permeability of liquid membranes containing macrocyclic carriers. Several new macrocyclic carriers were synthesized during the last three year period, including selenium-containing macrocycles, new crown-4 structures, and several new crown structures containing nitrogen based heterocycles as substituents in the principal macrocyclic ring. The cation binding properties of these macrocycles were investigated by potentiometric titration, calorimetric titration, solvent extraction, and NMR techniques. In addition, hydrophobic macrocycles were incorporated into dual hollow fiber membrane systems to investigate their membrane performance, especially in the proton-coupled transport mode. It was found that the dual hollow fiber system maintains the cation selectivity and permeability of supported liquid membranes, while enhancing membrane stability. The diffusion limited transport model was expanded to account for membrane solvent effects. Furthermore, Eu{sup 2+} transport was found to be similar to that of strontium and much higher than that of the lanthanides, in supported liquid membrane systems.
Date: June 10, 1991
Creator: Lamb, J. D.
Object Type: Report
System: The UNT Digital Library
On the development of a chemical kinetic measurement apparatus and the determination of the reaction rate constants for lithium-lead/steam interaction (open access)

On the development of a chemical kinetic measurement apparatus and the determination of the reaction rate constants for lithium-lead/steam interaction

An experimental set-up for accurate measurement of hydrogen generation rate in Lithium-Lead (Li{sub 17}Pb{sub 83}) Steam or water interactions is being designed. The most important features of the design include a selenoid actuated quick opening and closing butterfly valve used to control the reaction time and the placement of all measuring devices below a water line to minimize leakage of the hydrogen collected. 4 figs., 4 tabs.
Date: March 10, 1991
Creator: Biney, P.O.
Object Type: Report
System: The UNT Digital Library
Petroleum marketing monthly, October 1991. [Contains glossary] (open access)

Petroleum marketing monthly, October 1991. [Contains glossary]

This report is designed to give information and statistical data about a variety of crude oils and refined petroleum products. The publication provides statistics on crude oil costs and refined petroleum products sales for use by industry, government, private sector analysts, educational institutions, and consumers. Data on crude oil include the domestic first purchase price, the f.o.b. and landed cost of imported crude oil, and the refiner's acquisition cost of crude oil. Sales data for motor gasoline, distillates, residuals, aviation fuels, kerosene, and propane are presented. 12 figs., 55 tabs.
Date: October 10, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Phytochrome from green plants: Assay, purification, and characterization (open access)

Phytochrome from green plants: Assay, purification, and characterization

This funding period was directed at developing an in-depth molecular analysis of the low-abundance, 118,000 M{sub r} green-tissue phytochrome that had at that time been relatively recently identified as being distinct from the better characterized 124,000 M{sub r} phytochrome abundant in etiolated tissue. The specific objectives as stated in the original proposal were: (1) To generate monoclonal antibodies specific to the 118,000 M{sub r} green-tissue phytochrome. (2) To develop additional and improved procedures to permit progress toward the ultimate goal of purifying green-tissue phytochrome to homogeneity. (3) To initiate an alternative approach to determining the structural properties of green-tissue phytochrome by isolating and sequencing cDNA cones representing the 118,000 M{sub r} green-tissue polypeptide in Avena. This approach is based on and will test hypothesis that the 118,000 M{sub r} polypeptide is encoded by a gene(s) distinct from those encoding etiolated-tissue 124,000 M{sub r} phytochrome. (4) To utilize any such 118,000 M{sub r} phytochrome specific cDNA clones as hybridization probes to begin to investigate the structure, organization, and regulation of the corresponding gene(s) in Avena. (5) To begin to investigate the possible presence in other higher plant and algal species of sequences homologous to the 118,000 M{sub r} Avena polypeptide using …
Date: June 10, 1991
Creator: Quail, P.H. (California Univ., Berkeley, CA (United States). Dept. of Plant and Soil Biology Agricultural Research Service, Albany, CA (United States). Plant Gene Expression Center)
Object Type: Report
System: The UNT Digital Library
Pion interferometry and resonances in pp and AA collisions (open access)

Pion interferometry and resonances in pp and AA collisions

We study the sensitivity of pion interferometry in {bar p}p and {bar p}p collisions at ISR energies to the resonance abundance. We show that those data are not compatible with the full resonance fractions predicted by the Lund model. The preliminary S+S and O+Au data at 200 GeV are, however, not incompatible with the Lund predictions, although their sensitivity to resonances is significantly weaker than in the pp/{bar p}p case.
Date: December 10, 1991
Creator: Padula, S.S. (Universidade Estadual Paulista, Sao Paulo, SP (Brazil). Inst. de Fisica Teorica) & Gyulassy, M. (Lawrence Berkeley Lab., CA (United States))
Object Type: Article
System: The UNT Digital Library