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The multipulse Thomson scattering diagnostic on the DIII-D tokamak

Description: This paper describes the design and operation of a 40-spatial channel Thomson scattering system that uses multiple 20 Hz Nd:YAG lasers to measure the electron temperature and density profiles periodically throughout an entire plasma discharge. Interference filter polychromators disperse the scattered light which is detected by silicon avalanche photodiodes. The measurable temperature range from 10 eV to 20 keV and the minimum detectable density is about 2 {times} 10{sup 18} m{sup {minus}3}. Las… more
Date: September 1, 1991
Creator: Carlstrom, T. N.; Campbell, G. L.; DeBoo, J. C.; Evanko, R. G.; Evans, J.; Greenfield, C. M. et al.
Partner: UNT Libraries Government Documents Department
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Numerical simulation of a short RFQ resonator using the MAFIA codes

Description: The electrical characteristics of a short (2{beta}{lambda}=0.4 m) resonator with large modulation (m=4) have been studied using the three dimensional codes, MAFIA. The complete resonator, including the modulated electrodes and a complex support structure, has been simulated using {approximately} 350,000 mesh points. Important characteristics studied include the resonant frequency, electric and magnetic fields distributions, quality factor and stored energy. The results of the numerical simulati… more
Date: January 1, 1991
Creator: Wang, H.; Ben-Zvi, Ilan; Jain, A.; Paul, P. (State Univ. of New York, Stony Brook, NY (United States). Dept. of Physics) & Lombardi, A. (Istituto Nazionale di Fisica Nucleare, Legnaro (Italy). Lab. Nazionale di Legnaro)
Partner: UNT Libraries Government Documents Department
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INEX simulations of the optical performance of the AFEL

Description: The AFEL (Advanced Free-Electron Laser) Project at Los Alamos National Laboratory is presently under construction. The project's goal is to produce a very high-brightness electron beam which will be generated by a photocathode injector and a 20 MeV rf-linac. Initial laser experiments will be performed with a 1-cm-period permanent magnet wiggler which will generate intense optical radiation near a wavelength of 3.7 {mu}m. Future experiments will operate with slotted-tube'' electromagnetic wiggle… more
Date: January 1, 1991
Creator: Goldstein, J.C.; Wang, T.S.F. & Sheffield, R.L.
Partner: UNT Libraries Government Documents Department
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Decommissioning of a grout- and waste-filled storage tank in the 200 East Area of the Hanford Site

Description: A self-concentrating waste tank located at the Strontium Semiworks Facility in the 200 East Area of the Hanford Site will be decommissioned following waste removal. During a previous decommissioning phase, the tank, thought to be empty, was filled with grout to prevent it from collapsing over time. Several years later, an agitator rod was pulled from within the tank and found to contain significant amounts of radiation, indicating there was still radioactive waste in the tank. Several alternati… more
Date: January 1, 1991
Creator: Marske, S.G.
Partner: UNT Libraries Government Documents Department
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Prospects of physics at CDF with the SVX

Description: During next physics run CDF will strongly enhance its heavy flavor tagging capabilities with the installation of a silicon vertex detector (SVX), that will allow precise measurements of secondary decay vertices in the plane transverse to the beam (impact parameter resolution {approx equal} 12 {mu}m). We expect this detector to have a significant impact on b-physics (c{tau}{sub B} {approx equal} 350 {mu}m) and top search. In the following we will discuss CDF prospects for top search and for CP v… more
Date: September 1, 1991
Creator: Dell'Agnello, S.
Partner: UNT Libraries Government Documents Department
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Design and performance of liquid hydrogen target systems for the Fermilab Fixed Target Program

Description: The Fermilab 1990--1991 Fixed Target Program featured six experiments utilizing liquid hydrogen or liquid deuterium targets as part of their apparatus. Each design was optimized to the criteria of the experiment, resulting in variations of material selection, methods of refrigeration and secondary containment. Collectively, the targets were run for a total of 14,184 hours with an average operational efficiency of 97.6%. The safe and reliable operation of these targets was complemented by an inc… more
Date: July 1, 1991
Creator: Allspah, D.; Danes, J.; Peifer, J. & Stanek, R.
Partner: UNT Libraries Government Documents Department
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Brookhaven highlights for fiscal year 1991, October 1, 1990--September 30, 1991

Description: This report highlights Brookhaven National Laboratory's activities for fiscal year 1991. Topics from the four research divisions: Computing and Communications, Instrumentation, Reactors, and Safety and Environmental Protection are presented. The research programs at Brookhaven are diverse, as is reflected by the nine different scientific departments: Accelerator Development, Alternating Gradient Synchrotron, Applied Science, Biology, Chemistry, Medical, National Synchrotron Light Source, Nuclea… more
Date: January 1, 1991
Creator: Rowe, M.S.; Cohen, A.; Greenberg, D.; Seubert, L. & Kuper, J.B.H.
Partner: UNT Libraries Government Documents Department
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Experimental and theoretical investigations of marine stratocumulus cloud sensitivity to climate parameters using ship-trail clouds

Description: The formation and radiative properties of clouds are poorly parameterized in numerical climate models, especially marine boundary layer clouds. Twomey (1991), after describing the importance of cloud microphysics to the climate problem, states Clearly, many more field measurements and laboratory experiments are called for, rather than endless repetitions of computer simulations that are closely related to each other and parameterize in very similar ways.'' The effort described here is a field e… more
Date: January 1, 1991
Creator: Porch, W.; Buchwald, M.; Glatzmaier, T.; Kao, C.-Y.; Unruh, W. (Los Alamos National Lab., NM (United States)); Hudson, J. et al.
Partner: UNT Libraries Government Documents Department
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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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Measurements of Non-Leptonic Weak Decays of Lambda Hypernuclei

Description: Aspects of recent measurements of the mesonic and non-mesonic partial decay rates of {sub {Lambda}}{sup 5}He, and {sub {Lambda}}{sup 12}C are discussed. We comment on what the experiments tell us about the spin-isospin structure of {Delta}S=1 weak interaction in the nuclear environment. 14 refs., 1 fig.
Date: January 1, 1991
Creator: Schumacher, Reinhard A.
Partner: UNT Libraries Government Documents Department
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Photoinduced Charge Separation by Polymer-Bound Chromophores

Description: This project has examined the photodynamic behavior of water-soluble polymers that have covalently linked hydrophobic chromophores spaced along the chains. These polymeric systems have been examined for photoinduced charge separation with electron-accepting ions having different total charge. Focus has been on the excited singlet (S{sub 1}) state formed by laser flash absorption. The effects of pH and ionic strength -- factors that govern the conformational nature of the polymer in solution -- … more
Date: September 1, 1991
Creator: Rodgers, M. A. J.
Partner: UNT Libraries Government Documents Department
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Alkali sorber (RABSAM), September 1, 1990--August 30, 1991

Description: The objective of this work is to develop a regenerable activated-bauxite sorber alkali monitor that requires no high-temperature/high-pressure sampling line for the reliable in situ measurement of alkali-vapor concentration in the exhaust from the pressurized fluidized-bed combustion of coal. 11 refs., 2 figs., 1 tab.
Date: January 1, 1991
Creator: Lee, S. H. D. & Swift, M. W.
Partner: UNT Libraries Government Documents Department
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Physical fitness training reference manual for security force personnel at fuel cycle facilities possessing formula quantities of special nuclear materials

Description: The recommendations contained throughout this NUREG are being provided to the Nuclear Regulatory Commission (NRC) as a reference manual which can be used by licensee management as they develop a program plan for the safe participation of guards, Tactical Response Team members (TRTs), and all other armed response personnel in physical fitness training and in physical performance standards testing. The information provided in this NUREG will help licensees to determine if guards, TRTs, and other … more
Date: September 1, 1991
Creator: Arzino, P. A.; Caplan, C. S. & Goold, R. E. (California State Univ., Hayward, CA (United States). Foundation)
Partner: UNT Libraries Government Documents Department
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Continuum damping of low-n toroidicity-induced shear Alfven eigenmodes

Description: The effect of resonant continuum damping is investigated for the low-mode-number, toroidicity-induced, global shear Alfven eigenmodes, which can be self-excited by energetic circulating alpha particles in an ignited tokamak plasma. Resonant interaction with the shear Alfven continuum is possible for these eigenmodes, especially near the plasma periphery, leading to significant dissipation, which is typically larger than direct bulk plasma dissipation rates. Two perturbation methods are develope… more
Date: September 1, 1991
Creator: Berk, H.L.; Van Dam, J.W.; Guo, Z. & Lindberg, D.M.
Partner: UNT Libraries Government Documents Department
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An update on passive correctors for the SSC dipole magnets

Description: The concept of correction of the magnetization sextupole became a topic of discussion as soon as it was realized that superconductor magnetization could have a serious effect on the SSC beam during injection. Several methods of correction were proposed. These included (1) correction with active bore tube windings like those on the HERA machine which correct out magnetization sextupole and the sextupole due to iron saturation, (2) correction with persistent sextupole windings mounted on the bore… more
Date: May 1, 1991
Creator: Green, Michael A.
Partner: UNT Libraries Government Documents Department
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Geothermal Materials Development, Annual Report FY 1991

Description: Advances in the development of new materials, the commercial availabilities of which are essential for the attainment of Hydrothermal Category Level I and II Objectives, continue to be made in the Geothermal Materials Development Project. Many successes have already been accrued and the results used commercially. In FY 1991, utility company sponsored full cost'' recovery programs based upon materials technology developed in this project were initiated on topics such as condensing heat exchanger… more
Date: December 1, 1991
Creator: Kukacka, L. E.
Partner: UNT Libraries Government Documents Department
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Sonic enhanced ash agglomeration and sulfur capture

Description: The major objective of the Phase 1 test program is to confirm the feasibility of the Manufacturing and Technology Conversion International, Inc. bimodal particle size approach to enhance particulate control by acoustic ash agglomeration. An ancillary objective of the Phase 1 effort is to demonstrate and confirm the feasibility of an acoustic field to enhance sulfur capture by increasing sorbent reactivity. Phase 1 tests are designed to cover the frequency range between 50 and 1400 Hz, establish… more
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department
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Potential for use of high-temperature superconductors in fusion reactors

Description: The present rate of development of high-temperature superconductors (HTSs) is sufficiently rapid that there may be opportunities for their use in contemporary fusion devices such as the International Thermonuclear Experimental Reactor (ITER). The most likely 1application is for delivering power to the superconducting magnets, especially in substituting for the current leads between the temperatures of 4 K and 77K. A second possible application of HTSs is as a liquid-nitrogen-cooled power bus, c… more
Date: January 1, 1991
Creator: Hull, J.R.
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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Configuration Management Program Plan

Description: Westinghouse Savannah River Company (WSRC) has established a configuration management (CM) plan to execute the SRS CM Policy and the requirements of the DOE Order 4700.1. The Reactor Restart Division (RRD) has developed its CM Plan under the SRS CM Program and is implementing it via the RRD CM Program Plan and the Integrated Action Plan. The purpose of the RRD CM program is to improve those processes which are essential to the safe and efficient operation of SRS production reactors. This docume… more
Date: September 25, 1991
Partner: UNT Libraries Government Documents Department
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NQR-NMR studies of higher alcohol synthesis Cu-Co catalysts

Description: Copper and cobalt are the key elements in syngas conversion catalyst systems used for higher alcohol synthesis. Their proximity and synergy sensitively control the selectivity and efficiency of the process. It is believed that their outer electronic charge distribution which is responsible for their electrical and magnetic properties might be governing their catalytic properties also. To examine the correlation between catalytic and magnetic properties, a series of copper cobalt catalysts (Co/C… more
Date: January 14, 1991
Partner: UNT Libraries Government Documents Department
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Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties

Description: Several new types of silicon-containing preceramic polymers, i.e., poly(diorganosilacetylene) and poly(diorganosilvinylene) have been synthesized with molecular weights from 10,000 to 120,000. These polymers could be thermally converted to SiC with a moderate to high char yields. Ready solubility and good processability made these types of polymers attractive in their applications to ceramics. The thermal polymerization of diethynyldiphenyl-silane, which was reported in 1968 to afford poly(diph… more
Date: October 7, 1991
Creator: Pang, Yi.
Partner: UNT Libraries Government Documents Department
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