Computational models of a radiofrequency (RF) heating system and neutral-beam injector are presented. These physics packages, when incorporated into a particle simulation code allow one to simulate the auxiliary heating and fueling of fusion plasmas. The RF-heating package is based upon a quasilinear diffusion equation which describes the slow evolution of the heated particle distribution. The neutral-beam injector package models the charge exchange and impact ionization processes which transfer energy and particles from the beam to the background plasma. Particle simulations of an RF-heated and a neutral-beam-heated simple-mirror plasma are presented. 8 refs., 5 figs.
Large scale mechanical improvements were made on the 100th scale glass melter in building 774A following a shutdown in November, 1988. The circumstances regarding that shutdown were reported by P.M. Allen in DPST-89-345. By request, the Mechanical Development Group assumed responsibility for the work on SRL Service order DS-87042. This report describes the changes which were made, their purpose, and observations as to their effectiveness after approximately 4 weeks of operating with the improvements in-place. Recommendations for further improving the equipment are also noted. The old melter design, now superseded, is documented in drawings ST5-23838 through ST5-23847. As-built drawing arrangements and details for the new work is shown in drawings SK5-6191-LD through SK5-6197-LD. Other design details are referenced in the drawings which were developed for the new shielded cells Research Melter, ST5-25111 through ST5-25124.
This discussion will consider a number of points relevant to limitations, advantages and disadvantages of various arrangements of bunches in the Tevatron proton-antiproton collider. The considerations discussed here will be limited to: (a) bunch spacing symmetry and relation to the relative luminosity at B0 and D0 and the beam-beam interaction with separated beams; (b) bunch spacing constraints imposed by Main Ring RF coalescing and the optics of beam separation at B0 and D0; and (c) bunch spacing constraints imposed by injection and abort kicker timing requirements, and by the Antiproton Source RF unstacking process. 20 figs., 17 tabs.
Operational characteristics of the LANL electrorefining cell, a modified LANL electrorefining cell, and an advanced electrorefining cell (known as the CRAC cell) were determined. Average process yields achieved were: 75% for the LANL cell, 82% for the modified LANL cell, and 86% for the CRAC cell. All product metal from the LANL and modified LANL cells was within foundry specifications. Metal from one run in the CRAC cell exceeded foundry specifications for tantalum. The LANL and modified LANL cells were simple in design and operation, but product separation was more labor intensive than with the CRAC cell. The CRAC cell was more complicated in design but remained relatively simple in operation. A decision analysis concluded that the modified LANL cell was the preferred cell. It was recommended that the modified LANL cell be implemented by the Plutonium Recovery Project at Rocky Flats and that development of the CRAC cell continue. 8 refs., 22 figs., 12 tabs.
Using Microcline Thermochronology (MTC), we have investigated the hydrothermal maturity of the Salton Sea Geothermal Field, potential or hydrocarbon maturation associated with heating due to ridge subduction beneath accretionary prism sediments, developed a single crystal dating system which has proven to greatly enhance interpretations regarding MTC, and also have begun to develop sound theoretical and experimental techniques which truly revolutionize our understanding of argon systematics in K-feldspars. The following is a brief synopsis of these projects in accordance with Monitoring and Reporting of Program Performance.''
This report presents the details of the Mound Laboratory EPA-NPDES Quality Assurance Program, the DOE Quality Assessment Program Results, Proficiency Environmental Testing Program and Plutonium in Urine Quality Control for 1988.
Our experimental approach focuses on the use of enzymes which catalyze the addition of oxygen to organic compounds., In tailoring the application of these enzymes to coal processing, we are particularly interested in ensuring that oxidation occurs at sulfur and not at carbon-carbon bonds. Previous studies with DBT have shown that the reaction most frequently observed in microbial oxidative pathways is one in which DBT is oxidized at ring carbons. These reactions, as we have said, are accompanied by a considerable decrease in the energy content of the compound. In addition, microbial pathways have been identified in which the sulfur atom is sequentially oxidized to sulfoxide, to sulfone, to sulfonate, and finally to sulfuric acid. In this case, the fuel value of the desulfurized compounds is largely retained. We are evaluating the potential of commercially available enzymes to perform this function.
Our experimental approach focuses on the use of enzymes which catalyze the addition of oxygen to organic compounds., In tailoring the application of these enzymes to coal processing, we are particularly interested in ensuring that oxidation occurs at sulfur and not at carbon-carbon bonds. Previous studies with DBT have shown that the reaction most frequently observed in microbial oxidative pathways is one in which DBT is oxidized at ring carbons. These reactions, as we have said, are accompanied by a considerable decrease in the energy content of the compound. In addition, microbial pathways have been identified in which the sulfur atom is sequentially oxidized to sulfoxide, to sulfone, to sulfonate, and finally to sulfuric acid. In this case, the fuel value of the desulfurized compounds is largely retained. We are evaluating the potential of commercially available enzymes to perform this function.
The objective of this project is to construct and operate an integrated test circuit for the Molten-Caustic-Leaching (Gravimelt) process for desulfurization and demineralization of coal to prove process economics assumptions, deliver product coal and to test process conditions aimed at significantly lowering costs. The test circuit consists of six unit operations which together provide a continuous system for leaching coal and regenerating the reactant. These units are: (a) a kiln for reacting molten caustic with coal; (b) a seven stage water washing section for recovering caustic from the coal; (c) a three-stage acid washing section for removing the last traces of metals and alkali and providing an ultra pure coal product; (d) a water treatment section to provide either dischargeable or recyclable water; (e) a regeneration section to provide purified aqueous caustic; and (f) an evaporator section to provide molten-caustic for recycle to the kiln reactor. The integrated test circuit facility contains more than 160 pieces of equipment Including filters, centrifuges, tanks, reactors, feeders and the kiln and rising film evaporator. It occupies 3700 square fast and is fitted with more than 6000 foot of piping, 425 valves, 80 instruments and controls as well as a control room with computer control and data acquisition and reduction system. The highlight of last quarter was completion of a week of around-the-clock shakedown of the integrated test circuit. This quarter, the test circuit was put into operation and compliance coal was produced.
The photodecomposition of energetic nitrocompounds depends on the excitation energy, the light intensity which determines the mono-, bi- or multiphotonic character of the initial process and their gaseous, liquid or solid state. The initial processes of the photodecomposition of nitromethane and nitroalcanes are reviewed and their relevance to the initiation of energetic nitrocompounds detonation is discussed. The case of nitramines (dimethylnitramine and tutorial) is also briefly introduced.
We describe an ultra-high density scintillating fiber and tungsten calorimeter used as an active beam-dump for electrons. Data showing the calorimeter response to electrons with momenta between 50 and 350 GeV/c are presented. 9 figs.
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