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R and D recommendations for future ERDA switch requirements (open access)

R and D recommendations for future ERDA switch requirements

The following switches are briefly discussed: (1) high pressure and vacuum spark gaps, (2) liquid dielectric gaps, (3) solid dielectrics, (4) nonlinear ferromagnetic materials, (5) semiconductors, superconductors, (6) ferroelectric switches, (7) exploding wires, and (8) plasma instabilities. (MOW)
Date: April 16, 1976
Creator: Zucker, O. S.
System: The UNT Digital Library
Shell structure effects in compressed aluminum (open access)

Shell structure effects in compressed aluminum

Self-consistent augmented-plane-wave (APW) calculations of the T = 0 aluminum pressure-volume isotherm are reported from normal density to essentially the free-electron limit, and are compared to predictions based on statistical models. Two distinct density regimes are observed in which the APW and statistical model results differ fundamentally. In the first the L shell electrons are pressure ionized and in the second the K shell electrons are pressure ionized. The first of these occurs in the range 5-75 TPa, and the second in the range 2.3 x 10/sup 3/ - 1.1 x 10/sup 5/ TPa.
Date: June 16, 1977
Creator: McMahan, A. K. & Ross, M.
System: The UNT Digital Library
Ultrafast x-ray diagnostics for laser fusion experiments (open access)

Ultrafast x-ray diagnostics for laser fusion experiments

Temporally, spectrally, and spatially resolved x-ray emission diagnostics are important tools in the study of the heating and compression of laser fusion targets by sub-nanosecond laser pulses. The use of the Livermore 15 psec resolution x-ray streak camera to make such measurements is reviewed. Temporal histories of spectrally resolved x-ray emission in the 1 to 10 keV range have been obtained. These data have served to further define the x-ray streak camera as a quantative diagnostic tool and have also provided data relating to the absorption and compression phases of laser heating. The x-ray streak camera has been used in conjunction with a specially designed pinhole imaging system to temporally record images of laser compressed targets with a spatial resolution of approximately 6 ..mu..m. Implosion characteristics are presented for experiments with glass microshell targets. The concept, development, and testing of an ultrafast framing camera for full two-dimensional time resolved imaging is discussed. A prototype camera, based on the image dissection-restoration concept, has achieved an approximately 200 psec frame period with a resolution of 50 ..mu..m.
Date: August 16, 1976
Creator: Coleman, L. W.
System: The UNT Digital Library
Items from the construction of ESCAR (open access)

Items from the construction of ESCAR

ESCAR is an experimental superconducting accelerator which is being built at Lawrence Berkeley Laboratory to gain timely, full-scale experience in the construction and operation of a fully cryogenic accelerator. A report is given of the construction of several non-conventional items.
Date: March 16, 1977
Creator: Byrns, R. A.; Gilbert, W. S.; Lambertson, G. R.; Meuser, R. B. & Rechen, J. B.
System: The UNT Digital Library
Transport of intense ion beams (open access)

Transport of intense ion beams

The possibility of using intense bursts of heavy ions to initiate an inertially confined fusion reaction has stimulated interest in the transport of intense unneutralized heavy ion beams by quadrupole or solenoid systems. This problem was examined in some detail, using numerical integration of the coupled envelope equations for the quadrupole case. The general relations which emerge are used to develop examples of high energy transport systems and as a basis for discussing the limitations imposed by a transport system on achievable intensities for initial acceleration.
Date: March 16, 1977
Creator: Lambertson, G.; Laslett, L. J. & Smith, L.
System: The UNT Digital Library
Fiber array technique for subnanosecond x-ray framing camera (open access)

Fiber array technique for subnanosecond x-ray framing camera

A subnanosecond x-ray framing camera technique employing a fiber optics image dissector coupled to a 10 ps optical streak camera will be described. The output data from the streak camera can be reduced from photographic film or directly couple into a SEC Vidicon camera for immediate computer decoding of each scan line into a two dimensional picture. The use of the new subnanosecond plastic scintillator in front of the fiber optics dissector will also be discussed. The paper will include (1) the description of the basic principle, (2) fiber optics's image dissector construction, (3) time resolution considerations, and (4) experimental data on a prototype 7 by 7 array.
Date: August 16, 1976
Creator: Cheng, J. C.; Multhauf, L. G. & Tripp, G. R.
System: The UNT Digital Library
Mascon ages and sinking rates (open access)

Mascon ages and sinking rates

The long-term mechanical stability of strongly positive gravity anomalies (mascons) on the moon is evaluated from relevant physical characteristics of these bodies, from paleoselenotherms, and from the flow behavior of the lunar mantle. (auth)
Date: April 16, 1976
Creator: Heard, H. C.
System: The UNT Digital Library
Performance of a total-flow impulse turbine for geothermal applications (open access)

Performance of a total-flow impulse turbine for geothermal applications

A new, axial-flow impulse turbine was tested at LLL as part of the geothermal energy development program. Engine efficiency of this single-stage, two-phase expander was measured at 23% during a single-nozzle test. Performance predictions of a numerical model agreed with these results. Full-admission performance (based on the numerical-model and attainable nozzle thrust coefficients) indicates that engine efficiency can reach between 38 and 40% with present technology. Improved techniques for analyzing two-phase flow and further reduction of droplet sizes should provide 70% engine efficiency.
Date: May 16, 1977
Creator: Comfort, W. J., III
System: The UNT Digital Library
Precision surveying system for PEP (open access)

Precision surveying system for PEP

A semi-automatic precision surveying system is being developed for PEP. Reference elevations for vertical alignment will be provided by a liquid level. The short range surveying will be accomplished using a Laser Surveying System featuring automatic data acquisition and analysis.
Date: March 16, 1977
Creator: Gunn, J.; Lauritzen, T.; Sah, R. & Pellisier, P. F.
System: The UNT Digital Library
Wave-breaking amplitudes in warm, inhomogeneous plasmas (open access)

Wave-breaking amplitudes in warm, inhomogeneous plasmas

The effect of plasma temperature on reducing the wave-breaking amplitude of resonantly-driven fields is shown. Some applications to laser fusion are given.
Date: June 16, 1977
Creator: Kruer, W. L.
System: The UNT Digital Library
PEP magnet power supply systems (open access)

PEP magnet power supply systems

The dc electrical requirements of the PEP magnets fall mainly into two categories: (1) high power and current of single polarity and (2) low-power bi-polar. The first category will be thyristor-chopper controlled off common 600 V dc busses. The second group will utilize continuously controlled push-pull transistor actuators.
Date: March 16, 1977
Creator: Jackson, L. T.
System: The UNT Digital Library
Progress and Problems in Regional Numerical Weather Prediction (open access)

Progress and Problems in Regional Numerical Weather Prediction

None
Date: April 16, 1977
Creator: Kreitzberg, C. W.
System: The UNT Digital Library
Catalyzed gasification of biomass (open access)

Catalyzed gasification of biomass

Catalyzed biomass gasification studies are being conducted by Battelle's Pacific Northwest Laboratories. Investigations are being carried out concurrently at the bench and process development unit scales. These studies are designed to test the technical and economic feasibility of producing specific gaseous products from biomass by enhancing its reactivity and product specificity through the use of specific catalysts. The program is directed at controlling the gasification reaction through the use of specific catalytic agents to produce desired products including synthetic natural gas, ammonia synthesis gas (H/sub 2//N/sub 2/), hydrogen, or syn gas (H/sub 2//CO). Such gaseous products are currently produced in tonnage quantities from non-renewable carbonaceous resources, e.g., natural gas and petroleum. The production of high yields of these specified gases from biomass is accomplished through optimization of gasification conditions and proper choice of catalytic agents. For instance, high yields of synthetic natural gas can be attained through gasification with steam in the presence of gasification catalyst such as trona (Na/sub 2/CO/sub 3/ . NaHCO/sub 3/ . 2H/sub 2/O) and a nickel methanation catalyst. The gasification catalyst enhances the steam-biomass reaction while the methanation catalyst converts gaseous intermediates from this reaction to methane, the most thermodynamically stable hydrocarbon product. This direct …
Date: June 16, 1978
Creator: Sealock, L. J. Jr.; Robertus, R. J.; Mudge, L. K.; Mitchell, D. H. & Cox, J. L.
System: The UNT Digital Library
Gas-Cooled Reactors: the importance of their development (open access)

Gas-Cooled Reactors: the importance of their development

Gas-Cooled Reactors are considered to have a significant future impact on the application of fission energy. The specific types are the steam-cycle High-Temperature Gas-Cooled Reactor, the Gas-Cooled Fast Breeder Reactor, the gas-turbine HTGR, and the Very High-Temperature Process Heat Reactor. The importance of developing the above systems is discussed relative to alternative fission power systems involving Light Water Reactors, Heavy Water Reactors, Spectral Shift Controlled Reactors, and Liquid-Metal-Cooled Fast Breeder Reactors. A primary advantage of developing GCRs as a class lies in the technology and cost interrelations, permitting cost-effective development of systems having diverse applications. Further, HTGR-type systems have highly proliferation-resistant characteristics and very attractive safety features. Finally, such systems and GCFRs are mutally complementary. Overall, GCRs provide interrelated systems that serve different purposes and needs; their development can proceed in stages that provide early benefits while contributing to future needs. It is concluded that the long-term importance of the various GCRs is as follows: HTGR, providing a technology for economic GCFRs and HTGR-GTs, while providing a proliferation-resistant reactor system having early economic and fuel utilization benefits; GCFR, providing relatively low cost fissile fuel and reducing overall separative work needs at capital costs lower than those for LMFBRs; HTGR-GT (in …
Date: November 16, 1978
Creator: Kasten, P. R.
System: The UNT Digital Library
Experiment predictions of LOFT reflood behavior using the RELAP4/MOD6 code. [PWR] (open access)

Experiment predictions of LOFT reflood behavior using the RELAP4/MOD6 code. [PWR]

The RELAP4/MOD6 computer code was used to predict the thermal-hydraulic transient for Loss-of-Fluid Test (LOFT) Loss-of-Coolant Accident (LOCA) experiments L2-2, L2-3, and L2-4. This analysis will aid in the development and assessment of analytical models used to analyze the LOCA performance of commercial power reactors. Prior to performing experiments in the LOFT facility, the experiments are modeled in counterpart tests performed in the nonnuclear Semiscale MOD 1 facility. A comparison of the analytical results with Semiscale data will verify the analytical capability of the RELAP4 code to predict the thermal-hydraulic behavior of the Semiscale LOFT counterpart tests. The analytical model and the results of analyses for the reflood portion of the LOFT LOCA experiments are described. These results are compared with the data from Semiscale.
Date: October 16, 1978
Creator: Lin, J. C.; Kee, E. J.; Grush, W. H. & White, J. R.
System: The UNT Digital Library
Polarized proton acceleration (open access)

Polarized proton acceleration

The question of whether polarized beams of 12 GeV or, preferably, higher energy can be produced at other existing or planned accelerators is explored. Sources of polarized H/sup -/ ions suitable for injection into accelerators appear to be feasible with intensities in the milliampere range (an order of magnitude better than present performance at Argonne). This would be sufficient to produce polarized beams of intensities comparable (though somewhat weaker) to those of unpolarized beams in high energy accelerators and luminosities not more than a factor of about 10 lower than those for unpolarized beams in storage rings, such as the CERN ISR or ISABELLE, the 400 GeV storage accelerator system now under design at BNL. The major question, then, is whether it is possible to maintain polarization in these accelerators during the acceleration process and during storage in a storage ring.
Date: January 16, 1978
Creator: Courant, E. D.
System: The UNT Digital Library
Toxic Substances Control Act: a chemist's view (open access)

Toxic Substances Control Act: a chemist's view

The growing awareness of the hazards of chemicals in the environment has resulted in the passing of the Toxic Substances Control Act (TSCA) on Oct. 11, 1976. This paper attempts to cover some of the salient features of Public Law 94-469, EPA's approach to implementation of its provisions, and some of a chemist's perceptions of TSCA's prospects of success.
Date: June 16, 1978
Creator: Kland, M.J.
System: The UNT Digital Library
Nonoxide ceramic interactions with uranium or carbon. [Reaction of BN, TiN, HfC, CeS, or Ce2S3 with U, C, BeO, W, or Y2O3] (open access)

Nonoxide ceramic interactions with uranium or carbon. [Reaction of BN, TiN, HfC, CeS, or Ce2S3 with U, C, BeO, W, or Y2O3]

The interaction of possible nonoxide containment materials (including boron nitride, titanium nitride, hafnium carbide, and two cerium sulfides) with uranium or carbon has been examined by thermal analysis techniques. Additionally, nonoxide-ceramic interaction with beryllia, tungsten, or yttria was investigated. Hafnium carbide is the least reactive nonoxide ceramic tested.
Date: October 16, 1978
Creator: Holcombe, C.E.
System: The UNT Digital Library
Gamma spectrometric methods for measuring plutonium (open access)

Gamma spectrometric methods for measuring plutonium

Nondestructive analyses of plutonium can be made by detecting and measuring the gamma rays emitted by a sample. Although qualitative and semiquantitative assays can be performed with relative ease, only recently have methods been developed, using computer analysis techniques, that provide quantitative results. This paper reviews some new techniques developed for measuring plutonium. The features of plutonium gamma-ray spectra are reviewed and some of the computer methods used for spectrum analysis are discussed. The discussion includes a description of a powerful computer method of unfolding complex peak multiplets that uses the standard linear least-squares techniques of data analysis. This computer method is based on the generation of response profiles for the isotopes composing a plutonium sample and requires a description of the peak positions, relative intensities, and line shapes. The principles that plutonium isotopic measurements are based on are also developed, followed by illustrations of the measurement procedures as applied to the quantitative analysis of plutonium liquid and solid samples.
Date: February 16, 1978
Creator: Gunnink, R.
System: The UNT Digital Library
Flow field analysis (open access)

Flow field analysis

The average mean wind speed integrated over a disk is shown to be extremely close to the mean value of wind speed which would be measured at the center of a disk for most geometries in which a WECS (Wind Energy Conversion System) would operate. Field test results are presented which compare instantaneous records of wind speed integrated over a disk with the wind speed measured at the center of the disk. The wind field that a rotating element would experience is presented which has been synthesized from the outputs of an array of anemometers.
Date: January 16, 1978
Creator: Cliff, W.C.
System: The UNT Digital Library
Digital, realizable Wiener filtering in two-dimensions (open access)

Digital, realizable Wiener filtering in two-dimensions

The extension of Wiener's classical mean-square filtering theory to the estimation of two-dimensional (2-D), discrete random fields is discussed. In analogy with the 1-D case, the optimal realizable filter is derived by solution of a 2-D discrete Wiener--Hopf equation using a spectral factorization procedure. Computational algorithms for performing the required calculations are discussed. 3 figures.
Date: March 16, 1979
Creator: Ekstrom, M.P.
System: The UNT Digital Library
Review of the microscopic cross sections for the americium isotopes in the resolved resonance region. [0. 5 eV to 10 keV] (open access)

Review of the microscopic cross sections for the americium isotopes in the resolved resonance region. [0. 5 eV to 10 keV]

The differential cross section measurements for /sup 241/Am, /sup 242m/Am and /sup 243/Am are reviewed in the energy range from 0.5 eV to 10 keV. Parameters extracted from resonance analysis, such as the neutron strength function, the average level spacing, the average capture and fission widths, are compared for the various measurements. The average capture and fission cross sections from 100 eV to 10 keV are directly compared. The status of the data set is discussed with suggestions for further measurements. 24 references.
Date: November 16, 1978
Creator: Browne, J. C.
System: The UNT Digital Library
Effective H{sub 2}S abatement process using geothermal brine effluents (open access)

Effective H{sub 2}S abatement process using geothermal brine effluents

A simple and potentially inexpensive method for removal of H/sub 2/S from noncondensible gases evolved in geothermal flash processes has been successfully tested on a small scale in the field. The method consists of scrubbing the noncondensible gases of H{sub 2}S with brine effluents which contain relatively high concentrations of Pb, Zn, and Fe such as those of the Salton Sea and Brawley Geothermal Fields in the Imperial Valley, California. For plant applications, noncondensibles including H{sub 2}S would be ejected from a surface steam condenser (necessary to minimize the volume of liquid in contact with H/sub 2/) and scrubbed with effluent brine just prior to preinjection clarification. The metal sulfide precipitates are removed in the clarification step and the noncondensibles, less H{sub 2}S, are vented as usual.
Date: July 16, 1979
Creator: Quong, R.; Knauss, K.G.; Stout, N.D. & Owen, L.B.
System: The UNT Digital Library
Computer controlled ultrasonic inspection of pulsed magnetic welded fuel pins (open access)

Computer controlled ultrasonic inspection of pulsed magnetic welded fuel pins

Pulsed magnetic welding is being evaluated as a process for welding fuel cladding to the end plug for nuclear fuel pins. A continuous metallurgical bond is required between the plug and clad because this joint must function as a gas and coolant seal for the fuel pin. An ultrasonic technique utilizing a computer controlled scanner was developed to inspect these welds. First, fuel pin specimens were profiled in the weld zone region by determining actual surface coordinates. This step eliminated variable geometry effects and guaranteed proper transducer alignment during the scanning. Second, scans were made using positional information obtained during profiling, and ultrasonic data were digitized and stored for computer analysis. Third, analysis algorithms were used to recognize unbonded regions, and total unbonded area was calculated. Finally, A-scan and C-scan plots were generated by the computer.
Date: March 16, 1979
Creator: Horn, J. E.; Hunter, D. O. & Michaels, T. E.
System: The UNT Digital Library