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A unified theory of resonant excitation of kinetic ballooning modes by energetic ions/alpha particles in tokamaks

Description: A complete theory of wave-particle interactions is presented whereby both circulating and trapped energetic ions can destabilize kinetic ballooning modes in tokamaks. Four qualitatively different types of resonances, involving wave-precessional drift, wave-transit, wave-bounce, and precessional drift-bounce interactions, are identified, and the destabilization potential of each is assessed. For a characteristic slowing-down distribution function, the dominant interaction is that which taps thos… more
Date: October 1, 1991
Creator: Biglari, H. & Chen, L.
Partner: UNT Libraries Government Documents Department
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Non-linear instability of DIII-D to error fields

Description: Otherwise stable DIII-D discharges can become nonlinearly unstable to locked modes and disrupt when subjected to resonant m = 2, n = 1 error field caused by irregular poloidal field coils, i.e. intrinsic field errors. Instability is observed in DIII-D when the magnitude of the radial component of the m = 2, n = 1 error field with respect to the toroidal field is B{sub r21}/B{sub T} of about 1.7 {times} 10{sup {minus}4}. The locked modes triggered by an external error field are aligned with the … more
Date: October 1, 1991
Creator: La Haye, R. J. & Scoville, J. T.
Partner: UNT Libraries Government Documents Department
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Fifth high-energy heavy-ion study

Description: This was the fifth of a continuing series of summer studies held at LBL to discuss high energy heavy ion collisions. Recently, a similar meeting has been held on alternate years at GSI (Darmstadt); and, in 1979, we held a meeting at LBL exclusively devoted to ultra-relativistic nuclear collisions. Two new features distinguish this study from earlier meetings in the series. First, the energy range for discussion was broadened by including collisions from about 20 MeV/nucleon to the highest avail… more
Date: October 1, 1981
Partner: UNT Libraries Government Documents Department
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(Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

Description: This report presents information concerning field procedures employed during the monitoring, well construction, well purging, sampling, and well logging at the Wright-Patterson Air Force Base. Activities were conducted in an effort to evaluate ground water contamination.
Date: October 1, 1991
Partner: UNT Libraries Government Documents Department
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Establishment of viscometer capability for geopressured fluids. Project 61024 final report, November 19, 1978-December 31, 1979

Description: The feasibility of modifying the IGT capillary viscometer for the measurement of methane-saturated brines at 10,000 psi and 200/sup 0/C was evaluated. The viscometer was cleaned, modified, reassembled and pressure treated. The density cells were calibrated to a precision of approximately 7%. The viscosity of pure value was measured and the best value obtained was 6% below values reported in the literature. The operation of the viscometer was time-consuming and required meticulous cleaning betwe… more
Date: October 1, 1980
Creator: Rockar, E. & Randolph, P.
Partner: UNT Libraries Government Documents Department
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Two-photon physics

Description: A new experimental frontier has recently been opened to the study of two photon processes. The first results of many aspects of these reactions are being presented at this conference. In contrast, the theoretical development of research ito two photon processes has a much longer history. This talk reviews the many different theoretical ideas which provide a detailed framework for our understanding of two photon processes.
Date: October 1, 1981
Creator: Bardeen, W.A.
Partner: UNT Libraries Government Documents Department
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Final Report of Modeling of CWM Droplet Combustion

Description: The objective of the present study was to develop a one-dimensional, unsteady state model for coal-water mixture droplet combustion, and to compare the characteristic times for the various processes, such as water vaporization, devolatilization and char oxidation with available experimental data. A water film surrounding a spherical coal particle is considered to undergo vaporization by heat transfer from the hot air. After the water vaporization is complete, devolatilization begins. This proce… more
Date: October 1, 1983
Creator: Pandalai, Krish; Aggarwal, Suresh & Sirignano, William
Partner: UNT Libraries Government Documents Department
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Joining of ceramics for high performance energy systems. Mid-term progress report, August 1, 1979-March 31, 1980

Description: The subject program is primarily an exploratory and demonstration study of the use of silicate glass-based adhesives for bonding silicon-base refractory ceramics (SiC, Si/sub 3/N/sub 4/). The projected application is 1250 to 2050/sup 0/F relaxing joint service in high-performance energy conversion systems. The five program tasks and their current status are as follows. Task 1 - Long-Term Joint Stability. Time-temperature-transformation studies of candidate glass adhesives, out to 2000 hours sim… more
Date: October 6, 1980
Creator: Smeltzer, C E & Metcalfe, A G
Partner: UNT Libraries Government Documents Department
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Light Absorption and Scattering Mechanisms in Laser Fusion Plasmas

Description: The picture of laser light absorption and scattering which is emerging from theory and computer simulation studies of laser-plasma interactions is described. On the subject of absorption, we discuss theoretical and experimental evidence that resonance absorption in a steepened density profile is a dominant absorption mechanism. Recent work also indicates the presence of critical surface ripples, which we study using two and three dimensional computer simulations. Predictions of hot electron spe… more
Date: October 4, 1977
Creator: Barnes, C.; Estabrook, K. G.; Kruer, W. L.; Langdon, A. B.; Lasinski, B. F.; Max, C. E. et al.
Partner: UNT Libraries Government Documents Department
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Potential for efficient frequency conversion at high average power using solid state nonlinear optical materials

Description: High-average-power frequency conversion using solid state nonlinear materials is discussed. Recent laboratory experience and new developments in design concepts show that current technology, a few tens of watts, may be extended by several orders of magnitude. For example, using KD*P, efficient doubling (>70%) of Nd:YAG at average powers approaching 100 KW is possible; and for doubling to the blue or ultraviolet regions, the average power may approach 1 MW. Configurations using segmented apertur… more
Date: October 28, 1985
Creator: Eimerl, D.
Partner: UNT Libraries Government Documents Department
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Effect of fuel recycling on radioactivity and thermal power of high-level wastes

Description: The radioactivity and thermal power of high-level and plutonium-bearing wastes from the nuclear fuel cycle have been calculated for the years 1975 to 2005 using the rate of generation of such wastes projected for the Generic Environmental Statement on Mixed Oxide Fuel (NUREG-0002). Three modes of fuel recycle are considered: (1) no recycle, (2) uranium recycle, and (3) prompt uranium and plutonium recycle. These cases are compared with a respect to radioactivity and thermal power of the generat… more
Date: October 1, 1977
Creator: Wachter, J.W.
Partner: UNT Libraries Government Documents Department
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The interpretation of reflectometry measurements of plasma fluctuations

Description: Wave reflections from density fluctuations with magnitudes and frequencies typical of drift waves have been investigated. Both drift waves and the reflected phase and amplitude depend on the density gradient scale length, and this common feature implies that both the angular deviation of a normally propagating wave and the phase change on reflection are of order unity. Thus the surface will always appear rough'' and amplitude variations will always be large. For smaller amplitude waves numerica… more
Date: October 1, 1991
Creator: Bretz, N.
Partner: UNT Libraries Government Documents Department
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Thermodynamic model for calorimetric and phase coexistence properties of coal derived fluids

Description: On September 1, 1989 work was initiated on a project to extend the available vapor-liquid equilibrium (VLE) model for coal fluids to allow satisfactory predictions of excess enthalpies of coal liquids at high pressures. The available vapor liquid equilibrium model was developed with support from previous grant from DOE-PETC (Grant no. DE-FG22-89PC90541). The current project also involves measurement of some model compound VLE data and chromatographic characterization of coal liquids for distrib… more
Date: October 1, 1991
Creator: Kabadi, V. N.
Partner: UNT Libraries Government Documents Department
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High-energy proton radiation damage of high-purity germanium detectors

Description: Motivated by their applicability to gamma-ray spectroscopy experiments in space, quantitative studies of radiation damage effects in high-purity germanium detectors due to high-energy charged particles have been initiated with the irradiation by 6 GeV/c protons of two 1.0 cm thick planar detectors maintained at 88/sup 0/K. The threshold for resolution degradation and the annealing characteristics differs markedly from those previously observed for detectors irradiated by fast neutrons. Under pr… more
Date: October 1, 1977
Creator: Pehl, R.H.; Varnell, L.S. & Metzger, A.E.
Partner: UNT Libraries Government Documents Department
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Laser annealing of ion implanted CZ silicon for solar cell junction formation. Quarterly report No. 2

Description: Results on a contract to evaluate the merits of large spot size pulsed laser annealing of ion implanted silicon wafers for junction formation in solar cells are reported. Investigations on homogenization of the laser beam were continued. In addition to the 30 mm diameter fused silica rod with a 90/sup 0/ bend configuration, quartz tubes were obtained and briefly tried. Best results were obtained with the rod homogenizer. Laser annealing experimentation resulted in complete recrystallization of … more
Date: October 1, 1980
Creator: Katzeff, J. S.
Partner: UNT Libraries Government Documents Department
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Thermal energy storage for power generation

Description: Studies strongly indicate that the United States will face widespread electrical power constraints in the 1990s, with most regions of the country experiencing capacity shortages by the year 2000. In many cases, the demand for increased power will occur during intermediate and peak demand periods. Much of this demand is expected to be met by oil- and natural gas-fired Brayton cycle turbines and combined-cycle plants. While natural gas is currently plentiful and reasonably priced, the availabilit… more
Date: October 1, 1989
Creator: Drost, M. K.; Antoniak, Z. I.; Brown, D. R. & Sathyanarayana, K.
Partner: UNT Libraries Government Documents Department
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Calorimetric and optical beam diagnostics on the LBL 120-keV neutral beam test facility

Description: The 120-keV Neutral Beam Test Facility at LBL is fitted with several types of instrumentation to determine the properties of the 10- to 15-A hydrogen and deuterium beams produced in this facility. These include a neutral particle dump for measuring the temperature profile generated by the beam, and a fixed and a moveable ion dump to measure the temperature profiles generated by the various ion components after they have been swept out of the neutral beam by a bending magnet. These several dumps… more
Date: October 1, 1977
Creator: Burrell, C. F.; Cooper, W. S.; Steele, W. F. & Smith, R. R.
Partner: UNT Libraries Government Documents Department
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Continuing development of the DEROB system. Quarterly report, July 1, 1980-September 30, 1980

Description: The last module of the DEROB System has been reprogrammed and recoded in an effort to reduce the computational time and cost associated with using DEROB. Some preliminary tests have been carried out on the new program, and the tentative results show that the time of execution can be reduced anywhere from 7% to 40% of the time required by the previous version of DEROB. The variability in the improvement arises from the options specified by the user. Additional tests are being carried out to debu… more
Date: October 1, 1980
Creator: Arumi-Noe, F
Partner: UNT Libraries Government Documents Department
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Analytical model for a vertical buoyant jet

Description: An analytical model for a round and two-dimensional turbulent buoyant jet which is discharged vertically into a stagnant ambient is developed. The buoyant jet is considered to have three separate zone models which are matched to form a complete solution. The velocity field is determined for the entire jet and plume regions by the use of an eddy viscosity which varies along the axis of the jet. The centerline decay of buoyancy is determined throughout and the results are compared to existing num… more
Date: October 1, 1980
Creator: Lee, D. W.
Partner: UNT Libraries Government Documents Department
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The neutrinos in muon decay

Description: We review the available information on the identity of the neutrino states emitted in muon decay, and discuss the exotic decay {mu}{sup +} {yields} e{sup +} {bar {nu}}{sub e}{nu}{sub {mu}}. 22 refs.
Date: October 21, 1991
Creator: Herczeg, P.
Partner: UNT Libraries Government Documents Department
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Research in theoretical nuclear physics

Description: The work done during the past year covers three separate areas, low energy nuclear reactions intermediate energy physics, and nuclear structure studies. This manuscript summarizes our achievements made in these three areas.
Date: October 1, 1991
Creator: Udagawa, T.
Partner: UNT Libraries Government Documents Department
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A comparison of spanwise aerodynamic loads estimated from measured bending moments versus direct pressure measurements on horizontal axis wind turbine blades

Description: Two methods can be used to determine aerodynamic loads on a rotating wind turbine blade. The first is to make direct pressure measurements on the blade surface. This is a difficult process requiring costly pressure instrumentation. The second method uses measured flap bending moments in conjunction with analytical techniques to estimate airloads. This method, called ALEST, was originally developed for use on helicopter rotors and was modified for use on horizontal axis wind turbine blades. Esti… more
Date: October 1, 1991
Creator: Simms, D A & Butterfield, C P
Partner: UNT Libraries Government Documents Department
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Development of an extended-burnup Mark B design. First semi-annual progress report, July-December 1978. Report BAW-1532-1. [PWR]

Description: The primary objective of this program is to develop and demonstrate an improved PWR fuel assembly design capable of batch average burnups of 45,000-50,000 MWd/mtU. To accomplish this, a number of technical areas must be investigated to verify acceptable extended-burnup fuel performance. This report is the first semi-annual progress report for the program, and it describes work performed during the July-December 1978 time period. Efforts during this period included the definition of a preliminar… more
Date: October 1, 1979
Partner: UNT Libraries Government Documents Department
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