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Electromechanical Battery Program at the Lawrence Livermore National Laboratory (open access)

Electromechanical Battery Program at the Lawrence Livermore National Laboratory

New materials and new design concepts are being incorporated in a new approach to an old idea -- flywheel energy storage -- to create an important alternative to the electrochemical storage battery for use in electric vehicles or for stationary applications, such as computer back-up power or utility load-leveling. We visualize such EMBs (electromechanical batteries) as being modular in character, with small (1--5 kWh) modules being used for power-conditioning and for vehicular use, and paralleled 25 kWh modules being used for bulk storage, i.e., load-leveling, applications. In a funded program at the Laboratory two fractional kWh, 200 kW (design peak power) modules have been constructed and subjected to shake-down testing. Their design for high peak power was prompted by awareness of a particular commercial need, as a component in a power-line conditioning device. In addition to such stationary applications, the high power capability of our EMB designs makes them attractive for use in hybrid-electric vehicles. Important elements of the LLNL program include the development of passive magnetic bearings and the application of new high-efficiency permanent magnet arrays to an ironless generator/motor. Use of these particular elements, together with a multi-ring design for the flywheel rotor, is particularly conducive to a …
Date: May 31, 1994
Creator: Post, R. F.; Bender, D. A. & Merritt, B. T.
System: The UNT Digital Library
Review of electron beam microinstabilities and their relevance to EBIS devices (open access)

Review of electron beam microinstabilities and their relevance to EBIS devices

Plasma kinetic theory and some examples of microinstabilities are briefly reviewed. Although the velocity space configuration of any EBIS is inherently susceptible to a number of classical beam microinstabilities, the small radial dimension of an EBIS plasma may prevent modes from occurring in EBIS traps due to physical limitation. In EBIS devices with high electron beam compression, where the potential for beam microinstabilities is great, the radial dimension is smaller than the Debye length, which renders plasma kinetic theory invalid. Potential for parametric instabilities exists due to coupling of structure excited modes into plasma modes by various mode-mode coupling ``decay`` processes.
Date: May 31, 1994
Creator: Hershcovitch, A.
System: The UNT Digital Library
Limit on the rare decay B {yields} {mu}{sup +}{mu}{sup {minus}} K{sup {plus_minus}} (open access)

Limit on the rare decay B {yields} {mu}{sup +}{mu}{sup {minus}} K{sup {plus_minus}}

We report on a search for flavor-changing neutral current decays of B mesons into {mu}{mu}K{sup {plus_minus}} using data obtained in the Collider Detector at Fermilab (CDF) 1992--1993 data taking run. To reduce the amount of background in our data we use precise tracking information from the CDF silicon vertex detector to pinpoint the location of the decay vertex of the B candidate, and accept only events which have a large decay time. We compare this data to a B meson signal obtained in a similar fashion, but where the muon pears originate from {psi} decays, and calculate the relative branching ratios. In absence of any indication of flavor-changing neutral current decay we set an upper limit on the branching ratio of 3.2 {times} 10{sup {minus}1}, which is consistent with Standard Model expectations but leaves little room for non-standard physics.
Date: May 27, 1994
Creator: CDF Collaboration
System: The UNT Digital Library
Warm formability of aluminum-magnesium alloys (open access)

Warm formability of aluminum-magnesium alloys

Manufacturers have become increasingly interested in near-net-shape forming of aluminum alloys as a means to reduce production costs and the weight of aircraft and automotive structures. To achieve the ductilities required for this process, we have examined extended ductility of Al-Mg alloys in the warm forming, or Class I creep, regime. We have studied a high-purity, binary alloy of Al-2.8Mg and ternary alloys of Al-xMg-0.5Mn with Mg concentrations from 1.0 to 6.6 wt. %. Tensile tests, including strain rates-change tests, have been performed with these materials at temperatures of 300 and 400C over a range 10{sup {minus}4} to 2 {times} 10{sup {minus}2} s{sup {minus}1}. A maximum tensile failure strain of 325% for the binary alloy and a maximum of 125% in the ternary alloys have been measured. The experimental results have been used to evaluate the effects of solute concentration, microstructure, temperature, and strain rate on flow stress ({sigma}), elongation to failure (e{sub f}), and strain-rate sensitivity (m) of these alloys.
Date: May 27, 1994
Creator: Taleff, E. M.; Henshall, G. A.; Lesuer, D. R. & Nieh, T. G.
System: The UNT Digital Library
Beryllium based multilayers for normal incidence extreme ultraviolet reflectivity (open access)

Beryllium based multilayers for normal incidence extreme ultraviolet reflectivity

The need for normal incidence mirrors maintaining reflectivity greater than 60% for an industrially competitive Extreme Ultraviolet Lithography (EUV) system has been well documented. The Molybdenum/Silicon system has emerged as the de-facto standard, where researchers are now routinely fabricating mirrors demonstrating 63% reflectivity near 130 Angstroms. However, multilayer mirrors using beryllium as the low atomic number (low-Z) spacer could potentially show similar or better reflectivity, and operate at wavelengths down to the beryllium K-edge at 111 Angstroms. Besides offering potentially greater reflectivity, the shorter wavelength light offers increased dissolution depth in photoresists, and offers potentially better resolution and depth of focus. We will report our latest results from beryllium based multilayers. The mirrors were fabricated at the Lawrence Livermore National Laboratory (LLNL) and tested at the Center for X-Ray Optics at Lawrence Berkeley Laboratory (CXRO/LBL).
Date: May 26, 1994
Creator: Skulina, K. M.; Alford, C.; Bionta, R. M.; Makowiecki, D. M.; Kortright, J.; Soufli, R. et al.
System: The UNT Digital Library
Measurement of the polarization in the decay B{sup 0} {yields} J/{psi}K{sup *0} in {bar p}p collisions at {radical}s = 1.8 TeV (open access)

Measurement of the polarization in the decay B{sup 0} {yields} J/{psi}K{sup *0} in {bar p}p collisions at {radical}s = 1.8 TeV

This paper reports on the measurement of the polarization in the decay B{sup o} {yields} J/{psi}K{sup *o} using data collected at the collider Detector at Fermilab in {bar p}p collisions at {radical}s = 1.8 TeV. B{sup O} mesons were reconstructed through the decay chain B{sup o} {yields} J/{psi}K{sup *o}, J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}, K{sup *o} {yields} K{sup +}{pi}{sup {minus}}. A sample of 50 {plus_minus} 11 events was used in the measurement, yielding the result {Gamma}{sub L}/{Gamma} = 0.66 {plus_minus} 0.10 (stat) {sub {minus}}0.10 {sup +0.08} (sys).
Date: May 26, 1994
Creator: CDF Collaboration
System: The UNT Digital Library
Power conditioning for the National Ignition Facility (open access)

Power conditioning for the National Ignition Facility

A cost-effective, 320-MJ power-conditioning system has been completed for the proposed National Ignition Facility (NIF). The design features include metallized dielectric capacitors, a simple topology, and large (1.6-MJ) module size. Experimental results address the technical risks associated with the design.
Date: May 26, 1994
Creator: Larson, D. W.; Anderson, R. & Boyes, J.
System: The UNT Digital Library
Scoping economics for the commercial manufacture of metallocene catalysts (open access)

Scoping economics for the commercial manufacture of metallocene catalysts

This study assumes that commercial-scale production of propylene-based isotactic polymers with metallocene catalyst systems will become a reality. The challenge that must be overcome for commercial success with these propylene polymers is to discover a metallocene system recipe that will give sufficient catalyst activity along with the requisite stereo-selectivity at reasonable cost. Anticipating such a discovery, it is assumed here that the economics are well-represented by a catalyst system that consists in part of a silylene-bridged cyclopentadienyl zirconocene made in a batchwise process having an annual capacity of 15,000 pounds. Activation will be achieved with a cocatalyst such as methylaluminoxane (MAO), coated in conjunction with the catalyst on a support such as silica. The MAO at an estimated $100/lb contributes $1800/lb cost to the finished catalyst with an assumed recipe of 18:1 mass ratio of MAO to zirconocene. Based on a 20% return on investment, the selling price for the supported zirconocene system is estimated to be $2915/lb. The required capital investment to make 735,000 lb/yr of the total supported system is 9 million dollars. These estimates have {plus_minus}50% range of uncertainty. Payback period for this plant in a sold-out condition is three years. The catalyst system cost in ethylene-propylene …
Date: May 26, 1994
Creator: Brockmeier, N. F.
System: The UNT Digital Library
A Structural Determination Using Magnetic X-Ray Circular Dichroism in Spin-Polarized Photoelectron Diffraction (open access)

A Structural Determination Using Magnetic X-Ray Circular Dichroism in Spin-Polarized Photoelectron Diffraction

The first structural determination with spin-polarized, energy-dependent photoelectron diffraction using circularly-polarized x-rays is reported for Fe films on Cu(001). Circularly-polarized x-rays produce spin-polarized photoelectrons from the Fe 2p doublet, and intensity asymmetries in the 2p{sup 3/2} level are observed. . Fully spin-specific multiple scattering calculations reproduce the experimentally determined energy and angular dependences. A new analytical procedure which focuses upon intensity variations due to spin-dependent diffraction is introduced.
Date: May 26, 1994
Creator: Waddill, G. D.; Tobin, J. G.; Guo, X. & Tong, S. Y.
System: The UNT Digital Library
On the period of VY Ursae Majoris (open access)

On the period of VY Ursae Majoris

This article contains visual observation data of the carbon star VY Ursae Majoris.
Date: May 25, 1994
Creator: Ofek, Efran; Shemmer, Ohad & Gabzo, Ofer
System: The UNT Digital Library
Optical detection system for multispectral UV fluorescence laser remote sensing measurements (open access)

Optical detection system for multispectral UV fluorescence laser remote sensing measurements

A mobile laser remote sensing system is being developed for multispectral UV fluorescence detection of vapor, liquid, and solid effluents. TM system uses laser wavelengths between 250 and 400 nm to excite UV fluorescence spectra that can be used to detect and identify species in multicomponent chemical mixtures. With a scanning mirror assembly, the system is designed to map chemical concentrations with a range resolution of {approximately}5 m. In this paper we describe the optical detection system (scanning mirror assembly, 76 cm diameter collection telescope, relay optics, spectrometers, and detectors) associated data acquisition and control electronics. We also describe unique diagnostic software that is used for instrument setup and control.
Date: May 25, 1994
Creator: Tisone, G. C.; Clark, B.; Wakefield-Reyes, C.; Hargis, P. H., Jr.; Michie, B.; Downey, T. L. et al.
System: The UNT Digital Library
Determination of operating limits for radionuclides for a proposed landfill at Paducah Gaseous Diffusion Plant (open access)

Determination of operating limits for radionuclides for a proposed landfill at Paducah Gaseous Diffusion Plant

The operating limits for radionuclides in sanitary and industrial wastes were determined for a proposed landfill at the Paducah Gaseous Diffusion Plant (PGDP), Kentucky. These limits, which may be very small but nonzero, are not mandated by law or regulation but are needed for rational operation. The approach was based on analyses of the potential contamination of groundwater at the plant boundary and the potential exposure to radioactivity of an intruder at the landfill after closure. The groundwater analysis includes (1) a source model describing the disposal of waste and the release of radionuclides from waste to the groundwater, (2) site-specific groundwater flow and contaminant transport calculations, and (3) calculations of operating limits from the dose limit and conversion factors. The intruder analysis includes pathways through ingestion of contaminated vegetables and soil, external exposure to contaminated soil, and inhalation of suspended activity from contaminated soil particles. In both analyses, a limit on annual effective dose equivalent of 4 mrem (0.04 mSv) was adopted. The intended application of the results is to refine the radiological monitoring standards employed by the PGDP Health Physics personnel to determine what constitutes radioactive wastes, with concurrence of the Commonwealth of Kentucky.
Date: May 24, 1994
Creator: Wang, J. C.; Lee, D. W.; Ketelle, R. H.; Lee, R. R. & Kocher, D. C.
System: The UNT Digital Library
Heating and current drive systems for TPX (open access)

Heating and current drive systems for TPX

The heating and current drive (H and CD) system proposed for the TPX tokamak will consist of ion cyclotron, neutral beam, and lower hybrid systems. It will have 17.5 MW of installed H and CD power initially, and can be upgraded to 45 MW. It will be used to explore advanced confinement and fully current-driven plasma regimes with pulse lengths of up to 1,000 s.
Date: May 24, 1994
Creator: Swain, D.; Goranson, P.; Halle, A. von; Bernabei, S. & Greenough, N.
System: The UNT Digital Library
['UNT professor offers expertise of Barnes collection', May 22, 1994] (open access)

['UNT professor offers expertise of Barnes collection', May 22, 1994]

An article from the newspaper the Denton Record-Chronicle written by Tim Leenerts. The piece discusses the lectures given by Dr. R. William McCarter on the Barnes collection, which was being shown at the Kimbell Art Museum in Fort Worth.
Date: May 22, 1994
Creator: Leenerts, Tim
System: The UNT Digital Library
Development of an expert system for transportation of hazardous and radioactive materials (open access)

Development of an expert system for transportation of hazardous and radioactive materials

Under the sponsorship of the US Department of Energy`s (DOE`s) Transportation Management Division (EM-261), the Transportation Technologies Group at Oak Ridge National Laboratory (ORNL) has designed and developed an expert system prototype application of the hazardous materials transportation regulations. The objective of this task was to provide a proof-of-concept for developing a computerized expert system that will ensure straightforward, consistent, and error-free application of the hazardous materials transportation regulations. The expert system prototype entailed the analysis of what an expert in hazardous materials shipping information could/should do. From the analysis of the different features required for the expert system prototype, it was concluded that the developmental efforts should be directed to a Windows{trademark} 3.1 hypermedia environment. Hypermedia technology usually works as an interactive software system that gives personal computer users the ability to organize, manage, and present information in a number of formats--text, graphics, sound, and full-motion video.
Date: May 20, 1994
Creator: Ferrada, J. J.; Michelhaugh, R. D. & Rawl, R. R.
System: The UNT Digital Library
Techniques and results of tokamak-edge simulation (open access)

Techniques and results of tokamak-edge simulation

This paper describes recent development of the UEDGE code in three important areas. (1) Non-orthogonal grids allow accurate treatment of experimental geometries in which divertor plates intersect flux surfaces at oblique angles. (2) Radating impurities are included by means of one or more continuity equations that describe transport and sources, and sinks due to ionization and recombination processes. (3) Advanced iterative methods that reduce storage and execution time allow us to find fully converged solutions of larger problems (i.e., finer grids). Sample calculations are presented to illustrate these development.
Date: May 20, 1994
Creator: Smith, G. R.; Brown, P. N.; Rensink, M. E.; Rognlien, T. D.; Campbell, R. B.; Knoll, D. A. et al.
System: The UNT Digital Library
A centralized audio presentation manager (open access)

A centralized audio presentation manager

The centralized audio presentation manager addresses the problems which occur when multiple programs running simultaneously attempt to use the audio output of a computer system. Time dependence of sound means that certain auditory messages must be scheduled simultaneously, which can lead to perceptual problems due to psychoacoustic phenomena. Furthermore, the combination of speech and nonspeech audio is examined; each presents its own problems of perceptibility in an acoustic environment composed of multiple auditory streams. The centralized audio presentation manager receives abstract parameterized message requests from the currently running programs, and attempts to create and present a sonic representation in the most perceptible manner through the use of a theoretically and empirically designed rule set.
Date: May 16, 1994
Creator: Papp, A. L. III & Blattner, M. M.
System: The UNT Digital Library
The influence of phase changes on debris-cloud interactions with protected structures (open access)

The influence of phase changes on debris-cloud interactions with protected structures

The physical state of the debris cloud generated by the interaction of a projectile with a thin target depends on the energy balance associated with above the sound speeds of the impact event. At impact velocities well materials involved, the cloud is expected to be primarily molten, but with some vapor present. A series of numerical calculations using the multi-dimensional finite-difference hydrocode CTH has been used to evaluate the effect of phase changes (i.e., different vapor fractions) on these clouds, and their subsequent interaction with backwall structures. In the calculations, higher concentrations of vapor are achieved by increasing the initial temperature of both the projectile and the thin shield while keeping the impact velocity constant, and by actually increasing the impact velocity. The nature of the debris cloud and its subsequent loading on the protected structure depend on both its thermal and physical state. This interaction can cause rupture, spallation or simply bulging of the backwall. These computational results are discussed and compared with new experimental observations obtained at an impact velocity of {approximately}10 km/s. In the experiment, the debris cloud was generated by the impact of a plate-shaped titanium projectile with a thin titanium shield.
Date: May 16, 1994
Creator: Lawrence, R. J.; Kmetyk, L. N. & Chhabildas, L. C.
System: The UNT Digital Library
Temperature-Initiated Passive Cooling System (TIPACS) (open access)

Temperature-Initiated Passive Cooling System (TIPACS)

The Temperature-Initiated Passive Cooling System (TIPACS) is a recently invented passive cooling system that transfers heat from a hot, insulated system to a cooler, external environment. TIPACS has four defining characteristics: efficient heat-transfer, passive with no moving components, thermal switch mechanism that allows heat transfer only above a preset temperature, and one-way (heat diode) heat transfer. Example applications include cooling (1) building attics, (2) electrical sheds, (3) chemical reactors, (4) utility-load-leveling batteries, and (5) nuclear reactor containments. TIPACS was evaluated for cooling a modular high-temperature gas-cooled reactor (MHTGR) cavity. This evaluation indicates potential performance and economic advantages.
Date: May 16, 1994
Creator: Forsberg, C. W. & Conklin, J. C.
System: The UNT Digital Library
EAGLES 1.1: A microcomputer software package for analyzing fuel efficiency of electric and gasoline vehicles (open access)

EAGLES 1.1: A microcomputer software package for analyzing fuel efficiency of electric and gasoline vehicles

As part of the U.S. Department of Energy`s electric/hybrid vehicle research program, Argonne National Laboratory has developed a computer software package called EAGLES. This paper describes the capability of the software and its many features and potential applications. EAGLES version 1.1 is an interactive microcomputer software package for the analysis of battery performance in electric-vehicle applications, or the estimation of fuel economy for a gasoline vehicle. The principal objective of the electric-vehicle analysis is to enable the prediction of electric-vehicle performance (e.g., vehicle range) on the basis of laboratory test data for batteries. The model provides a second-by-second simulation of battery voltage and current for any specified velocity/time or power/time profile, taking into consideration the effects of battery depth-of-discharge and regenerative braking. Alternatively, the software package can be used to determine the size of the battery needed to satisfy given vehicle mission requirements (e.g., range and driving patterns). For gasoline-vehicle analysis, an empirical model relating fuel economy, vehicle parameters, and driving-cycle characteristics is included in the software package. For both types of vehicles, effects of heating/cooling loads on vehicle performance can be simulated. The software package includes many default data sets for vehicles, driving cycles, and battery technologies. EAGLES 1.1 …
Date: May 15, 1994
Creator: Marr, W. M.
System: The UNT Digital Library
Effects of battery technologies, driving patterns, and climate comfort control on the performance of electric vehicles (open access)

Effects of battery technologies, driving patterns, and climate comfort control on the performance of electric vehicles

A computer software package, EAGLES, has been developed at Argonne National Laboratory to analyze electric vehicle (EV) performance. In this paper, we present EAGLES predictions of EV driving range, acceleration rate, and energy consumption under various driving patterns, with different battery technologies, and with assumptions concerning use of air conditioners and/or heaters for climate comfort control. The specifications of a baseline, four-passenger EV for given design performance requirements are established, assuming urban driving conditions represented by the Los Angeles 92 (LA-92) driving cycle and using battery characteristics similar to those of the United States Advanced Battery Consortium (USABC) midterm battery performance goals. To examine the impacts of driving patterns, energy consumption is simulated under three different driving cycles: the New York City Cycle, the Los Angeles 92 Cycle, and the ECE-15 Cycle. To test the impacts of battery technologies, performance attributes of an advanced lead-acid battery, the USABC midterm battery goals, and the USABC long-term battery goals are used. Finally, EV energy consumption from use of air conditioners and/or heaters under different climates is estimated and the associated driving range penalty for one European city (Paris) and two United States cities (Chicago and Los Angeles) is predicted. The results of …
Date: May 15, 1994
Creator: Marr, W. W.; Wang, M. Q. & Santini, D. J.
System: The UNT Digital Library
The NO to NO{sub 2} conversion by ethylene oxidation (open access)

The NO to NO{sub 2} conversion by ethylene oxidation

A well-stirred reactor experiment and chemical kinetic modeling effort were performed in order to study the effect of ethylene oxidation on the conversion of nitric oxide (NO) to nitrogen dioxide (NO{sub 2}). Parameters examined in this study were temperature (1003--1260K) and input hydrocarbon concentration (220--3270 ppmv wet). The stirred reactor residence time was maintained at {approximately}2 milliseconds. Kinetic calculations indicated the NO to NO{sub 2} conversion proceeded through the ``HO{sub 2} mechanism``, NO + HO{sub 2} {yields} NO{sub 2} + OH, and the majority of the conversion occurred within the well-stirred reactor. The chemical kinetic mechanism used to model the percent conversion of the NO to NO{sub 2}, C{sub 2}H{sub 4}, CH{sub 4}, CO and CO{sub 2} concentrations showed excellent agreement with the experimental data, thereby validating the ethylene oxidation mechanism. Reaction pathway analysis and logarithmic sensitivity analysis were combined to analyze the ethylene oxidation structure and HO{sub 2} production process. The analysis revealed the primary ethylene oxidation pathway has the potential to form two HO{sub 2} radicals per ethylene consumed, thus making the ethylene a significant agent in promoting conversion of NO to NO{sub 2}. The secondary ethylene oxidation pathway is a potent chain branching process which furthers ethylene …
Date: May 13, 1994
Creator: Marinov, N. M.; Steele, R. C.; Malte, P. C. & Hori, M.
System: The UNT Digital Library
Impact of nuclear data on fast neutron therapy (open access)

Impact of nuclear data on fast neutron therapy

By combining a new, all-particle Monte Carlo radiation transport code, PEREGRINE, with the Lawrence Livermore National Laboratory (LLNL) nuclear data base, we have studied the importance of various neutron reactions on dose distributions in biological materials. Monte Carlo calculations have been performed for 5--20 MeV neutron pencil beams incident on biologically relevant materials arranged in several simple geometries. Results highlight the importance of nuclear data used for calculating dose distributions resulting from fast neutron therapy.
Date: May 12, 1994
Creator: Hartmann-Siantar, C. L.; Chandler, W. P.; Rathkopf, J. A.; Resler, D. A.; Cox, L. J.; Chadwick, M. B. et al.
System: The UNT Digital Library
Committee on Interagency Radiation Research and Policy Coordination (CIRRPC) (open access)

Committee on Interagency Radiation Research and Policy Coordination (CIRRPC)

Enclosed are proceedings of the workshop on Internal Dosimetry held on Atlanta, Georgia in April 1992. The recommendations from the Workshop were considered by the CIRRPC Subpanel on Occupational Radiation Protection Research in identifying those areas to be undertaken by individual Federal Agencies or in cooperative efforts. This document presents summaries of the following sessions: A.1 Applications and limitations of ICRP and other metabolic models, A.2 Applications and implementation of proposed ICRP lung model, A.3 Estimates of intake from repetitive bioassay data, A.4 Chelation models for plutonium urinalysis data, B.1 Transuranium/uranium registry data, B.2 Autopsy tissue analysis, B.3 Bioassay / Whole body counting, B.4 Data base formatting and availability, C.1 An overview of calculational techniques in use today, C.2 The perfect code, C.3 Dose calculations based on individuals instead of averages, C.4 From macro dosimetry to micro dosimetry.
Date: May 10, 1994
Creator: unknown
System: The UNT Digital Library