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Peripheral thresholds and Regge asymptotic expansions (open access)

Peripheral thresholds and Regge asymptotic expansions

None
Date: May 10, 1974
Creator: Chew, G. F. & Koplik, J.
System: The UNT Digital Library
Diffusion due to a single wave in a magnetized plasma (open access)

Diffusion due to a single wave in a magnetized plasma

Hamiltonian methods are used to study the motion of a particle in the field BZ and a single electrostatic wave. The particle motion is studied by numerically integrating the equations of motion. Diagrams of various particle trajectories are given. (MOW)
Date: May 10, 1976
Creator: Smith, G. R. & Kaufman, A. N.
System: The UNT Digital Library
EMP protection technology interchange (open access)

EMP protection technology interchange

Investigation and assessment of the potential degrading and destructive effects associated with the nuclear electromagnetic (EMP) phenomena has created a large technological base. This base is indeed quite broad owing to the unique and system-pervasive character of the EMP. One of the aims of an emerging discipline, such as that associated with EMP, is to provide for adequate transfer and integration of the developing technology into the overall engineering community. The needs of the community and how EMP hardening and protection information can be transferred or exchanged are reviewed. Many of the current and generally available sources of information are listed, examples of interchange methods are provided, and problems of developing specifications, standards, and suitable guidelines for design and incorporation of protection are also discussed.
Date: May 10, 1977
Creator: Martin, L. C.
System: The UNT Digital Library
Enhancement of methane production in the anaerobic digestion of sewage sludges (open access)

Enhancement of methane production in the anaerobic digestion of sewage sludges

The effect of powdered activated carbon on stressed anaerobic digesters utilizing a sewage sludge substrate was evaluated. The addition of carbon resulted in increased methanee production and greater process stability. The degree of enhancement appeared to be proportional to carbon concentration over the dose range studied (500-10,000 mg/l). A maximum increase in methane production of about 150% was observed at the highest carbon dose. The effect of 1500 mg/l carbon, 4000 mg/l coal, and 4000 mg/l flyash on relatively unstressed digesters was also examined. Units using a sewage sludge substrate were operated at 10 and 20 day SRT's. A 12% increase in methane production was observed in a carbon dosed digester functioning at a 10 day detention time. Enhancement was not evident with carbon at a 20 day SRT. No significant improvement in methane production was obtained in any of the digesters using coal or flyash as additives. Using the experimental data, a technique was developed for estimating the efficiencies of the methane forming and acid forming steps in the anaerobic digestion process. The results indicated that in stressed systems both stages of the digestion process were enhanced by the addition of powdered carbon. In the relatively unstressed systems, when …
Date: May 10, 1978
Creator: Spencer, R. R.
System: The UNT Digital Library
Experience with a high order programming language on the development of the Nova distributed control system (open access)

Experience with a high order programming language on the development of the Nova distributed control system

This paper explores the impact of an HOL on the development of the distributed computer control system for Nova laser fusion facility. As the world's most powerful glass laser, Nova will generate 150 trillion watt pulses of infrared light focused onto fusion targets a few millimeters in diameter. It will perform experiments designed to explore the feasibility of fusion as an energy source of the future. Nova will utilize fifty microcomputers and four VAX-11/780's in a distributed process control computer system architecture.
Date: May 10, 1983
Creator: Suski, G.J.; Holloway, F.W. & Duffy, J.M.
System: The UNT Digital Library
Extended overpower transient testing of oxide pins in EBR-II (open access)

Extended overpower transient testing of oxide pins in EBR-II

Understanding of the behavior of oxide fuel and blanket pins during slow transients with ramps between 0.1 and 10%/s is of importance because of the higher likelihood of such operational transient events. Compared to faster transients for which a fair amount of knowledge exists through testing in TREAT, there is also some concern of whether the oxide pins are particularly vulnerable to slower transients. For these reasons, a cooperative program between the US Department of Energy (DOE) and the Japanese Power Reactor and Nuclear Fuel Development Corporation (PNC) was launched to conduct operational transient testing (OTT) on oxide pins in EBR-II. A total of eleven tests is included in this OTT program. The status of the five extended-overpower-transient tests on preirradiated EBR-II pins is the subject of this paper.
Date: May 10, 1983
Creator: Tsai, H. & Neimark, L.A.
System: The UNT Digital Library
Study of heavy element structure with in-beam. cap alpha. /sup -/,. beta. /sup -/ and. gamma. -ray spectroscopy (open access)

Study of heavy element structure with in-beam. cap alpha. /sup -/,. beta. /sup -/ and. gamma. -ray spectroscopy

We describe our in-beam superconducting conversion electron spectrometer and its use in a (t,p) proton-conversion electron coincidence mode. Several examples of completed and on-going investigations are presented. These include: E0 strength from the /sup 238/U fission isomer; electromagnetic properties of the J/sup ..pi../ = 6/sup +/ and 8/sup +/ states of /sup 210/Pb; single particle and cluster states of /sup 213/Fr; the J/sup ..pi../ = 21/2/sup +/ isomer in /sup 197/Au and /sup 199/Au; and the cluster states of /sup 199/Au. Results of the study of odd-odd deformed /sup 244/Am are presented. The latter results performed using neutron-capture gamma-ray and conversion electron techniques are compared to recent developments in the modeling of deformed odd-odd nuclei. 23 refs., 10 figs., 1 tab.
Date: May 10, 1984
Creator: Meyer, R. A.; Decman, D. J.; Henry, E. A.; Hoff, R. W.; Mann, L. G.; Struble, G. L. et al.
System: The UNT Digital Library
Impact of long-lived radionuclides on waste classification for fusion (open access)

Impact of long-lived radionuclides on waste classification for fusion

A major goal for commercial applications of fusion reactors is to minimize radioactive wastes and to dispose of them by near-surface burial. There currently are no regulations specifically applicable to fusion wastes but those in force for fission wastes furnish a framework for expected fusion regulations. This paper recommends that all nuclides with half-lives greater than five years be assigned concentration limits as done in 10CFR61 for fission wastes. The paper gives approximate limits for all the significant long half-life sources of gamma radiation in the currently known periodic table. In the absence of working fusion reactors, computer models must be used to estimate the expected actual concentrations of radioactive nuclides. These estimates are needed to guide design parameters to achieve minimum radioactivity in fusion reactors. It is believed that the computer models and nuclear reaction libraries must be much more comprehensive than ordinarily used today to do activation calculations.
Date: May 10, 1985
Creator: Maninger, R.C.
System: The UNT Digital Library
Numerical studies of high current beam compression in heavy ion fusion (open access)

Numerical studies of high current beam compression in heavy ion fusion

The process of longitudinal compression of a drifting heavy ion pulse to be used as an ICF driver is examined with the aid of particle simulation. Space charge forces play a vital role in halting compression before the final focus lens system is reached. This must take place with minimal growth of transverse emittance and momentum spread. Of particular concern is the distortion of longitudinal phase space by the rounded transverse profile of the longitudinal self-electric field.
Date: May 10, 1985
Creator: Bisognano, J.; Lee, E. P. & Mark, J. W. K.
System: The UNT Digital Library
Hadron collisions at TEV energies (open access)

Hadron collisions at TEV energies

This paper discusses the need for higher energy accelerators to probe the mysteries of the subatomic universe. Intermediate vector bosons are discussed as well as symmetry breaking and the standard model. (LSP)
Date: May 10, 1988
Creator: Cahn, R. N.
System: The UNT Digital Library
Start-effect measurement of high FEL (free-electron laser) electric fields in MTX (Microwave Tokamak Experiment) by laser-aided particle-probe spectroscopy (open access)

Start-effect measurement of high FEL (free-electron laser) electric fields in MTX (Microwave Tokamak Experiment) by laser-aided particle-probe spectroscopy

We are constructing a diagnostic system to measure the electric field (>100 kV/cm) of a free-electron laser (FEL) beam when injected into the plasma of the Microwave Tokamak Experiment (MTX). The apparatus allows a crossed-beam measurement, with 2-cm spatial resolution in the plasma, involving the FEL beam (with 140-GHz, {approx}1-GW ECH pulses), a neutral-helium beam, and a dye-laser beam. After the laser beam pumps metastable helium atoms to higher excited states, their decay light is detected by an efficient optical system. Because of the Stark effect arising from the FEL electric field ({rvec E}), a forbidden transition can be strongly induced. The intensity of emitted light resulting from the forbidden transition is proportional to E{sup 2}. Because photon counting rates are estimated to be low, extra effort is made to minimize background and noise levels. It is possible that the lower {rvec E} of an MTX gyrotron-produced ECH beam with its longer-duration pulses can also be measured using this method. Other applications of the apparatus described here may include measurements of ion temperature (using charge-exchange recombination), edge-density fluctuations, and core impurity concentrations.
Date: May 10, 1990
Creator: Oda, T.; Takiyama, K. (Hiroshima Univ. (Japan)); Odajima, K.; Ohasa, K.; Shiho, M. (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan)); Mizuno, K. (California Univ., Davis, CA (USA) Lawrence Livermore National Lab., CA (USA)) et al.
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.
System: The UNT Digital Library
[SIAM conference on optimization] (open access)

[SIAM conference on optimization]

Abstracts are presented of 63 papers on the following topics: large-scale optimization, interior-point methods, algorithms for optimization, problems in control, network optimization methods, and parallel algorithms for optimization problems.
Date: May 10, 1992
Creator: unknown
System: The UNT Digital Library
[SIAM conference on optimization] (open access)

[SIAM conference on optimization]

Abstracts are presented of 63 papers on the following topics: large-scale optimization, interior-point methods, algorithms for optimization, problems in control, network optimization methods, and parallel algorithms for optimization problems.
Date: May 10, 1992
Creator: unknown
System: The UNT Digital Library
A real-time monitoring/emergency response workstation using a 3-D numerical model initialized with SODAR (open access)

A real-time monitoring/emergency response workstation using a 3-D numerical model initialized with SODAR

Many workstation based emergency response dispersion modeling systems provide simple Gaussian models driven by single meteorological tower inputs to estimate the downwind consequences from accidental spills or stack releases. Complex meteorological or terrain settings demand more sophisticated resolution of the three-dimensional structure of the atmosphere to reliably calculate plume dispersion. Mountain valleys and sea breeze flows are two common examples of such settings. To address these complexities, we have implemented the three-dimensional-diagnostic MATHEW mass-adjusted wind field and ADPIC particle-in-cell dispersion models on a workstation for use in real-time emergency response modeling. Both MATHEW and ADPIC have shown their utility in a variety of complex settings over the last 15 years within the Department of Energy`s Atmospheric Release Advisory Capability project.
Date: May 10, 1993
Creator: Lawver, B. S.; Sullivan, T. J. & Baskett, R. L.
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
EBIT x-ray spectroscopy studies for applications to photo-pumped x-ray lasers (open access)

EBIT x-ray spectroscopy studies for applications to photo-pumped x-ray lasers

Several pumping mechanisms have been suggested for x-ray lasers including collisional excitation, recombination, photo-ionization and photo-pumping. The success of photo-pumping as an x-ray laser scheme hinges on sufficient overlap of the emission and adsorption lines. For such a scheme to exhibit gain, the difference of the energies of the two lines must be within the line widths determined by the plasma dynamics, such as Doppler and opacity broadening. Typically, an overlap of a few parts in 10{sup 4} is required. Due to correlation effects, high-n levels of multi-electron ions are difficult to calculate and are reliable to roughly a part in 10{sup 3}. These differences are large enough to preclude accurate predictions of successful overlaps. As a result, precise measurements of the overlaps are needed. The continued interest in photo-pumping schemes lies in its potential to improve the laser output. It also allows the excitation of lasing transitions not accessible to other mechanisms and thus to the test laser kinetics from a different perspective. We have studied several such photo-pumping schemes at the LLNL electron beam ion trap. The N-like isoelectronic sequence 3d-5f and 3d-6f transitions were studied for photo-pumping by He-like ions, the Ne-like 2p-4d transitions were studied for …
Date: May 10, 1994
Creator: Elliott, S. R.; Beiersdorfer, P. & Nilsen, J.
System: The UNT Digital Library
Optimized hydrogen piston engines (open access)

Optimized hydrogen piston engines

Hydrogen piston engines can be simultaneously optimized for improved thermal efficiency and for extremely low emissions. Using these engines in constant-speed, constant-load systems such as series hybrid-electric automobiles or home cogeneration systems can result in significantly improved energy efficiency. For the same electrical energy produced, the emissions from such engines can be comparable to those from natural gas-fired steam power plants. These hydrogen-fueled high-efficiency, low-emission (HELE) engines are a mechanical equivalent of hydrogen fuel cells. HELE engines could facilitate the transition to a hydrogen fuel cell economy using near-term technology.
Date: May 10, 1994
Creator: Smith, J. R.
System: The UNT Digital Library
Livermore Imaging Fourier Transform Infrared Spectrometer (LIFTIRS) (open access)

Livermore Imaging Fourier Transform Infrared Spectrometer (LIFTIRS)

Lawrence Livermore National Laboratory is currently operating a hyperspectral imager, the Livermore Imaging Fourier Transform Infrared Spectrometer (LIFTIRS). This instrument is capable of operating throughout the infrared spectrum from 3 to 12.5 {mu}m with controllable spectral resolution. In this presentation we report on it`s operating characteristics, current capabilities, data throughput and calibration issues.
Date: May 10, 1995
Creator: Carter, M. R.; Bennett, C. L.; Fields, D. J. & Lee, F. D.
System: The UNT Digital Library
Series hybrid vehicles and optimized hydrogen engine design (open access)

Series hybrid vehicles and optimized hydrogen engine design

Lawrence Livermore, Sandia Livermore and Los Alamos National Laboratories have a joint project to develop an optimized hydrogen fueled engine for series hybrid automobiles. The major divisions of responsibility are: system analysis, engine design and kinetics modeling by LLNL; performance and emission testing, and friction reduction by SNL; computational fluid mechanics and combustion modeling by LANL. This project is a component of the Department of Energy, Office of Utility Technology, National Hydrogen Program. We report here on the progress on system analysis and preliminary engine testing. We have done system studies of series hybrid automobiles that approach the PNGV design goal of 34 km/liter (80 mpg), for 384 km (240 mi) and 608 km (380 mi) ranges. Our results indicate that such a vehicle appears feasible using an optimized hydrogen engine. The impact of various on-board storage options on fuel economy are evaluated. Experiments with an available engine at the Sandia Combustion Research Facility demonstrated NO{sub x} emissions of 10 to 20 ppm at an equivalence ratio of 0.4, rising to about 500 ppm at 0.5 equivalence ratio using neat hydrogen. Hybrid vehicle simulation studies indicate that exhaust NO{sub x} concentrations must be less than 180 ppm to meet the …
Date: May 10, 1995
Creator: Smith, J. R.; Aceves, S. & Van Blarigan, P.
System: The UNT Digital Library
A Comparison of the Electrochemical Behavior of Carbon Aerogels and Activated Carbon Fiber Cloths (open access)

A Comparison of the Electrochemical Behavior of Carbon Aerogels and Activated Carbon Fiber Cloths

Electrochemical capacitative behavior of carbon aerogels and commercial carbon fiber cloths was studied in 5M KOH, 3M sulfuric acid, and 0.5M tetrethylammonium tetrafluoroborate/propylene carbonate electrolytes. The resorcinol-formaldehyde based carbon aerogels with a range of denisty (0.2-0.85 g/cc) have open-cell structures with ultrafine pore sizes (5-50 nm), high surface area (400-700 m{sup 2}/g), and a solid matrix composed of interconnected particles or fibers with characteristic diameters of 10 nm. The commercial fiber cloths in the density range 0.2-04g/cc have high surface areas (1000-2500 m{sup 2}/g). The volumetric capacitances of high-density aerogels are shown to be comparable to or exceeding those from activated carbon fibers. Electrochemical behavior of these materials in various electrolytes is compared and related to their physical properties.
Date: May 10, 1996
Creator: Tran, T. D.; Alviso, C. T.; Hulsey, S. S.; Nielsen, J. K. & Pekala, R. W.
System: The UNT Digital Library
Graphitized needle cokes and natural graphites for lithium intercalation (open access)

Graphitized needle cokes and natural graphites for lithium intercalation

This paper examined effects of heat treatment and milling (before or after heat treatment) on the (electrochemical) intercalating ability of needle petroleum coke; natural graphite particles are included for comparison. 1 tab, 4 figs, 7 refs.
Date: May 10, 1996
Creator: Tran, T. D.; Spellman, L. M.; Pekala, R. W.; Goldberger, W. M. & Kinoshita, K.
System: The UNT Digital Library
[Newspaper Article: Railroad and Pioneer Museum slates benefit luncheon for Santa Fe depot] (open access)

[Newspaper Article: Railroad and Pioneer Museum slates benefit luncheon for Santa Fe depot]

Newspaper article about a luncheon planned by the Temple Railroad and Pioneer Museum to raise money for the restoration of historic downtown Temple. Included with the article is a photo of the Santa Fe depot before World War I.
Date: May 10, 1996
Creator: Ray, Randy
System: The Portal to Texas History
Status of immobilization for disposition of surplus fissile materials (open access)

Status of immobilization for disposition of surplus fissile materials

An international team was assembled for the purpose of selecting suitable immobilization forms and processing technologies for the Fissile Materials Deposition Program Office. As a reference point, the team used the NAS study but did not limit their recommendations to those of the NAS. As a result, two basic forms were selected and the processing alternatives to provide those two forms were defined. Environmental data have been supplied to support a preliminary environmental impact statement for the disposition program. The immobilization program has also entered the R&D Phase and progress has been made on the formulation of both glass and ceramic forms. Samples of both glass and ceramics containing tens of grams of plutonium have been prepared which indicate that the required concentration range can be obtained. Long-term leach tests to verify performance requirements in the repository are also under way.
Date: May 10, 1996
Creator: Gray, L.W. & Kan, T.
System: The UNT Digital Library