A multilevel preconditioner for domain decomposition boundary systems (open access)

A multilevel preconditioner for domain decomposition boundary systems

In this note, we consider multilevel preconditioning of the reduced boundary systems which arise in non-overlapping domain decomposition methods. It will be shown that the resulting preconditioned systems have condition numbers which be bounded in the case of multilevel spaces on the whole domain and grow at most proportional to the number of levels in the case of multilevel boundary spaces without multilevel extensions into the interior.
Date: December 11, 1991
Creator: Bramble, J.H.; Pasciak, J.E. & Xu, Jinchao.
Object Type: Article
System: The UNT Digital Library
Systematic investigation of electron impact excitation-autoionization from the groud state of highly charged GaI-like ions through. Delta. N=1 transitions (open access)

Systematic investigation of electron impact excitation-autoionization from the groud state of highly charged GaI-like ions through. Delta. N=1 transitions

A systematic variation in the line intensity ratios of GaI-like and ZnI-like ions of rare earth elements has been recently observed in spectra emitted in a low density, high temperature tokamak plasma. This variation is shown to be correlated with the gradual opening of autoionizing channels through inner-shell excited configurations of the GaI-like charge-state. These channels enhance the indirect ionization rate of GaI-like ions through excitation-autoionization (EA), effecting the ionization balance and temperatures of greatest abundance. We present a systematic investigation of EA and direct impact ionization (DI) in the GaI-like isoelectronic sequence from Mo (Z = 42) to Dy (Z = 66). As Z decreases from Dy to Pr (Z = 59) the levels of the configuration 3d{sup 9}4p4f, which are excited from the ground state by strong dipole collisional transitions, gradually cross the first ionization limit of the ion and are responsible for this ionization enhancement. When Z decreases further an additional channel is opened through the configuration 3d{sup 9}4p4d. 9 refs., 3 figs., 1 tab.
Date: January 11, 1991
Creator: Oreg, J.; Bar-Shalom, A. (Israel Atomic Energy Commission, Beersheba (Israel). Nuclear Research Center-Negev); Goldstein, W.H. (Lawrence Livermore National Lab., CA (USA)); Mandlebaum, P.; Mittnik, D.; Meroz, E. et al.
Object Type: Article
System: The UNT Digital Library
Lectures on accelerator physics (open access)

Lectures on accelerator physics

This report contains lecture notes on beam dynamics and acceleration concepts in particle accelerators. (LSP)
Date: March 11, 1991
Creator: Luccio, A.
Object Type: Article
System: The UNT Digital Library
An ESME update (v. 7. 2) (open access)

An ESME update (v. 7. 2)

The program ESME for modeling the longitudinal degree of freedom of beam dynamics in proton synchrotrons was described in considerable detail in User's Guide to ESME v. 7.1'' distributed about a year ago. This note corrects minor errors and omissions in the User's Guide, discusses bugs and crochets, notes fixes, and reports a few enhancements. Current work and plans are sketched. This note should be adequate to update the User's Guide. 8 refs.
Date: February 11, 1991
Creator: MacLachlan, J.A.
Object Type: Report
System: The UNT Digital Library
Relativistic nuclear many-body theory (open access)

Relativistic nuclear many-body theory

Nonrelativistic models of nuclear systems have provided important insight into nuclear physics. In future experiments, nuclear systems will be examined under extreme conditions of density and temperature, and their response will be probed at momentum and energy transfers larger than the nucleon mass. It is therefore essential to develop reliable models that go beyond the traditional nonrelativistic many-body framework. General properties of physics, such as quantum mechanics, Lorentz covariance, and microscopic causality, motivate the use of quantum field theories to describe the interacting, relativistic, nuclear many-body system. Renormalizable models based on hadronic degrees of freedom (quantum hadrodynamics) are presented, and the assumptions underlying this framework are discussed. Some applications and successes of quantum hadrodynamics are described, with an emphasis on the new features arising from relativity. Examples include the nuclear equation of state, the shell model, nucleon-nucleus scattering, and the inclusion of zero-point vacuum corrections. Current issues and problems are also considered, such as the construction of improved approximations, the full role of the quantum vacuum, and the relationship between quantum hadrodynamics and quantum chromodynamics. We also speculate on future developments. 103 refs., 18 figs.
Date: September 11, 1991
Creator: Serot, B.D. (Indiana Univ., Bloomington, IN (United States)) & Walecka, J.D. (Southeastern Universities Research Association, Newport News, VA (United States). Continuous Electron Beam Accelerator Facility)
Object Type: Article
System: The UNT Digital Library
Plant growth is influenced by glutamine synthetase-catalyzed nitrogen metabolism (open access)

Plant growth is influenced by glutamine synthetase-catalyzed nitrogen metabolism

Ammonia assimilation has been implicated as participating in regulation of nitrogen fixation in free-living bacteria. In fact, these simple organisms utilize an integrated regulation of carbon and nitrogen metabolism; we except to observe an integration of nitrogen and carbon fixation in plants; how could these complex systems grow efficiently and compete in the ecosystem without coordinating these two crucial activities We have been investigating the role of ammonia assimilation regulating the complex symbiotic nitrogen fixation of legumes. Just as is observed in the simple bacterial systems, perturbation of ammonia assimilation in legumes results in increased overall nitrogen fixation. The perturbed plants have increased growth and total nitrogen fixation capability. Because we have targeted the first enyzme in ammonia assimilation, glutamine synthetase, this provides a marker that could be used to assist selection or screening for increased biomass yield. 45 refs., 4 tabs.
Date: June 11, 1991
Creator: Langston-Unkefer, P.J.
Object Type: Article
System: The UNT Digital Library
Status report on the Advanced Light Source control system (open access)

Status report on the Advanced Light Source control system

This paper is a status report on the ADVANCED LIGHT SOURCE (ALS) control system. The current status, performance data, and future plans will be discussed. Manpower, scheduling, and costs issues are addressed.
Date: November 11, 1991
Creator: Magyary, S.; Chin, M.; Fahmie, M.; Lancaster, H.; Molinari, P.; Robb, A. et al.
Object Type: Article
System: The UNT Digital Library
Damage Analysis and Fundamental Studies for Fusion Reactor Materials Development (open access)

Damage Analysis and Fundamental Studies for Fusion Reactor Materials Development

During this period work has encompassed: (a) development of electropotential drop techniques to monitor the growth of cracks in steel specimens for a variety of specimen geometries; (b) micromechanical modeling of fracture using finite element calculations of crack and notch-tip stress and strain fields; (3) examining helium effects on radiation damage in austenitic and ferritic stainless steels; (4) analysis of the degradation of the mechanical properties of austenitic stainless steels for the purpose of assessing the feasibility of using these steels in ITER; (5) development of an integrated approach to integrity assessment; and (6) development of advanced methods of measuring fracture properties.
Date: January 11, 1993
Creator: Odette, G. R. & Lucas, G. E.
Object Type: Report
System: The UNT Digital Library
Object technology: A white paper (open access)

Object technology: A white paper

Object-Oriented Technology (OOT), although not a new paradigm, has recently been prominently featured in the trade press and even general business publications. Indeed, the promises of object technology are alluring: the ability to handle complex design and engineering information through the full manufacturing production life cycle or to manipulate multimedia information, and the ability to improve programmer productivity in creating and maintaining high quality software. Groups at a number of the DOE facilities have been exploring the use of object technology for engineering, business, and other applications. In this white paper, the technology is explored thoroughly and compared with previous means of developing software and storing databases of information. Several specific projects within the DOE Complex are described, and the state of the commercial marketplace is indicated.
Date: May 11, 1992
Creator: Jordan, S. R.; Arrowood, L. F.; Cain, W. D.; Stephens, W. M. & Vickers, B. D.
Object Type: Report
System: The UNT Digital Library
Chemistry of coal-related microparticles (open access)

Chemistry of coal-related microparticles

A new type of electrodynamic balance was designed, constructed and applied to the study of the chemistry of macerals and the chemical reaction between CaO sorbent particles and SO[sub 2]. The single-particle device was coupled to a Raman spectrometer. With this balance a single electrically charged microparticle is suspended in visible and infrared laser beams by means of superposed ac and dc electrical fields. The apparatus was designed to permit gas flow through the chamber so that gas-solid and gas-liquid chemical reactions can be carried out. A visible laser beam was used to illuminate the particle for Raman and fluorescence measurements, and an infrared laser beam was used to heat the particle. An overview of the experimental system is presented in Figure 1. The levitated particles were heated from two sides using a CO[sub 2] laser operating at the infrared wavelength of 10.6 [mu]m. The optical system used to direct the heating laser beam to the target is shown in Figure 2. Infrared detectors indicated in Figure 1 were used to measure the particle temperature by two-color pyrometery. A new technique was explored to independently determine the particle temperature; the method involves measuring the ratio of the intensities of Stokes …
Date: January 11, 1993
Creator: Davis, E.J. & Krieger-Brockett, B.
Object Type: Report
System: The UNT Digital Library
K-edge densitometer (KED) (open access)

K-edge densitometer (KED)

In 1979, a K-edge densitometer (KED) was installed by the Safeguards Assay group from Los Alamos National Laboratory in the PNC reprocessing plant at Tokai-mura, Japan. It uses an active nondestructive assay technique, KED, to measure the plutonium concentration of the product solution. The measurement uncertainty of an assay depends on the count time chosen, but can be 0.5% or better. The computer hardware and software were upgraded in 1992. This manual describes the operation of the instrument, with an emphasis on the user interface to the software.
Date: February 11, 1993
Creator: Sprinkle, J. K. & Hansen, W. J.
Object Type: Report
System: The UNT Digital Library
Full-scale demonstration Low-NO sub x Cell trademark Burner retrofit (open access)

Full-scale demonstration Low-NO sub x Cell trademark Burner retrofit

The Low-NO{sub x} Cell{trademark} Burner operates on the principle of staged combustion. The lower burner of each two-nozzle cell is modified to accommodate all the fuel input previously handled by two nozzles. Secondary air, less than theoretically required for complete combustion, is introduced to the lower burner. The remainder of secondary air is directed to the upper port'' of each cell to complete the combustion process. B W/EPRI have thoroughly tested the LNCB{trademark} at two pilot scales (6 million Btu per hour and 100 million Btu per hour), and tested a single full-scale burner in a utility boiler. Combustion tests at two scales have confirmed NO{sub x} reduction with the low-NO{sub x} cell on the order of 50% relative to the standard cell burner at optimum operating conditions. The technology is now ready for full unit, full-scale demonstration.
Date: May 11, 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Requirements for characterization of DWPF canister welds and labels, and estimates of service life (open access)

Requirements for characterization of DWPF canister welds and labels, and estimates of service life

The Department of Energy has established specifications for the DWPF product, which require that the DWPF provide estimates of the service life of the canister label, provide assurance that the DWPF canister will be leaktight when shipped, demonstrate that the contents of the canistered waste form will not lead to internal corrosion of the canister. The DWPF has elected to meet these requirements, in part, by characterizing canisters produced in the facility during the Startup Test Program. This includes canisters filled on the pour turntable (normal conditions) and canisters filled on the drain turntable (credible upset conditions expected to be more severe due to higher temperatures). This document identifies the requirements for characterization of the canister fabrication welds and canister labels (characterization of canister closure welds is being performed by Equipment Engineering Section), and for estimation of their service life in DWPF's Glass Waste Storage Building.
Date: January 11, 1993
Creator: Plodinec, M.J.; Harbour, J.R. & Marra, S.L.
Object Type: Report
System: The UNT Digital Library
Photoionization and electron transfer in ionic crystals (open access)

Photoionization and electron transfer in ionic crystals

Three lines of work have been completed since our previously submitted proposal. These are: spectroscopy of Ce{sup 3+} {minus} Na{sup +} pairs in CaF{sub 2} and SrF{sub 2}, photoionization studies of Sm{sup 2+}, Eu{sup 2+} and Yb{sup 2+} in CaF{sub 2} and SrF{sub 2}; and infrared-detected two-photon spectroscopy of MgO:Ni{sup 2+}, and other two-photon spectroscopy studies. These are discussed in this report.
Date: September 11, 1990
Creator: McClure, D.S.
Object Type: Report
System: The UNT Digital Library
Liquid centrifugation for nuclear waste partitioning (open access)

Liquid centrifugation for nuclear waste partitioning

The performance of liquid centrifugation for nuclear waste partitioning is examined for the Accelerator Transmutation of Waste Program currently under study at the Los Alamos National Laboratory. Centrifugation might have application for the separation of the LiF-BeF{sub 2} salt from heavier radioactive materials fission product and actinides in the separation of fission product from actinides, in the isotope separation of fission-product cesium before transmutation of the {sup 137}Cs and {sup 135}Cs, and in the removal of spallation product from the liquid lead target. It is found that useful chemical separations should be possible using existing materials for the centrifuge construction for all four cases with the actinide fraction in fission product perhaps as low as 1 part in 10{sup 7} and the fraction of {sup 137}CS in {sup 133}Cs being as low as a few parts in 10{sup 5}. A centrifuge cascade has the advantage that it can be assembled and operated as a completely closed system without a waste stream except that associated with maintenance or replacement of centrifuge components.
Date: March 11, 1992
Creator: Bowman, C. D.
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

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 Fischer-Tropsch (FT) 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 thirteenth 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 on the testing of the system hardware and software. H{sub 2} chemisorption capacities and activity selectivity data were also measured for three iron catalysts promoted with 1% alumina. 47 refs., 8 figs., 1 tab.
Date: October 11, 1990
Creator: Bartholomew, C. H.
Object Type: Report
System: The UNT Digital Library
Silicon crystal under bending (open access)

Silicon crystal under bending

The mechanical behavior of a silicon crystal under bending is investigated. For a crystal of length 30 mm and thickness 3 mm, to achieve the specified bend angle of 0.64 mrad, the appropriate angle of the aluminum punches is 0.96 mrad.
Date: February 11, 1993
Creator: Tang, Z.
Object Type: Report
System: The UNT Digital Library
X-ray diffraction measurement of residual stresses in delta plutonium (open access)

X-ray diffraction measurement of residual stresses in delta plutonium

Residual stresses in delta plutonium can be measured by the x-ray diffractometer method. This was accomplished with the aid of an experimental tantalum x-ray target. Preliminary experiments are encouraging and indicate that stresses may be determined precisely and rapidly. Future work will involve determination of x-ray elastic constants, instrument calibration with stress-free standards, higher x-ray power and more sophisticated monochromatization methods. 4 refs., 4 figs., 1 tab.
Date: September 11, 1990
Creator: Steinmeyer, P.A.
Object Type: Report
System: The UNT Digital Library
X-Ray Holography at Lawrence Livermore National Laboratory (open access)

X-Ray Holography at Lawrence Livermore National Laboratory

The x-ray holography program at the Lawrence Livermore National Laboratory has two principal goals: (1) the development of x-ray diffraction techniques for DNA sequence analysis and (2) the development of x-ray laser holography for structural analysis of intact biological cells and organelles. DNA sequence analysis will be accomplished by applying x-ray diffraction techniques to determine the ensemble average of the sequence of labels along the individual elements of crystalline DNA. X-ray laser holographic imaging will be accomplished by applying three dimensional x-ray holography to elucidate the structure of few hundred angstrom objects such as 300 {Angstrom} chromatin fibers, nuclear pores and nucleic acid replication complexes in living cells. Existing laboratory x-ray lasers will be utilized to produce flash x-ray holograms of the biological structures.
Date: October 11, 1990
Creator: Trebes, J.; Annese, C.; Birdsall, D.; Brase, J.; Gray, J.; Lane, S. et al.
Object Type: Article
System: The UNT Digital Library
System to inject steam and product oil from the same wellbore through downhole valve switching (open access)

System to inject steam and product oil from the same wellbore through downhole valve switching

The detailed design of a sliding sleeve valve operated by wireline has been completed. This Downhole Valve is obtained by modifications of two 2 7/8 in. commercial wireline-retrievable sleeve assemblies,which will be used to connect one of the upper branches of the patented Dual Whipstock to the 2 3/8 in. steam tubing,through a thermal expansion joint. Detailed engineering drawings and materials specifications have been completed. The design of the 30 ft-long joint comprising an H joint at the top a dual whipstock at the bottom and flow control devices for up to three drainholes equipped with 1.75 in. liners has been completed for a 7 in. cased well. This combination may be used in multi-layered reservoirs as well as in single layered reservoirs. It is also compatible with rod pump locations either above the kick-off pointsor near the base of the curved part of the drainhole liners. This design provides sufficient flexibility for most potential applications in the California market.
Date: June 11, 1993
Creator: Gondouin, M.
Object Type: Report
System: The UNT Digital Library
HIJET with AGS physics and N[sup *]'s (open access)

HIJET with AGS physics and N[sup *]'s

We investigate the effects of secondary interactions in nucleus- nucleus and proton-nucleus collisions using a modified HIJET Monte Carlo generator. The effects of N[sup *] production is explored and it is found that the numbers of kaons can almost be explained by their inclusion. However the transverse momentum spectrum of the kaons is not explained, since their production in HIJET is a soft secondary scattering process and not a hot thermal process like the data.
Date: February 11, 1993
Creator: Longacre, R. S.
Object Type: Article
System: The UNT Digital Library
Effect of pretreating of host oil on coprocessing (open access)

Effect of pretreating of host oil on coprocessing

The principal objective of this research is to determine the role that host petroleum-derived oils (1000 [degree]F[sup +]), as that of catalytically treated host oils, play when used as liquefaction solvents in coprocessing with coal. The host oils will be extensively characterized and then pretreated in a number of ways which involve catalytic reactions such as hydrogenation, hydrocracking, and isomerization. The pretreated oils will then be characterized by elemental analysis, catalytic dehydrogenation, and NMR. The effects of the host oil on coprocessing with coal will be compared to those obtained using catalytically modified heavy oils. When appropriate, model compounds will be used to study specific reactions brought about by the pretreatments. A total of 18 pretreatment runs have been made on an AMOCO vacuum tower residuum, VTR, in an attempt to increase its hydrogen content from 10.2 wt % to a level of about 11.5%. This pretreatment resulted in a significant increase in the hydrogen content of the starting oil (10.2 wt % to 11.2%).
Date: May 11, 1993
Creator: Wender, I. & Tierney, J.W.
Object Type: Report
System: The UNT Digital Library
Petroleum marketing monthly, September 1990. [Contains Glossary] (open access)

Petroleum marketing monthly, September 1990. [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, education 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 refiners' acquisition cost of crude oil. Sales data for motor gasoline, distillates, residuals, aviation fuels, kerosene, and propane are presented. 12 figs., 55 tabs.
Date: December 11, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Neutral strange particle production at the AGS (open access)

Neutral strange particle production at the AGS

We present the results of [Lambda] and K[sub s[sup o]] production from Si and Pb targets with 14.6[times][Lambda] Gev/c Si beams. The measured rapidity distributions and the transverse mass exponential slopes are presented and compared with models.
Date: February 11, 1993
Creator: Saulys, A.C.
Object Type: Article
System: The UNT Digital Library