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Investigation of impurity radiation from a well diganosed, laser heated plasma sample. Final report

Description: The results are described of an experimental and theoretical program designed to measure the relative intensities of line radiation from various ionization stages of carbon and helium impurities added to a deuterium plasma, and to relate the observed line intensity ratios to the plasma temperature. A deuterium sample plasma is produced and heated to a temperature of 2 to 7 eV at an electron density of 5 x 10/sup 16/ cm/sup -3/. The plasma parameters are monitored at various discrete times durin… more
Date: November 1, 1977
Creator: Crawford, E.; Quimby, D.; Hoffman, A. & Pietrzyk, Z.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cross Sections for X-Ray Photoelectron-Induced Desorption of Hydrogen Ions From Metal Surfaces

Description: We have measured the cross sections for x-ray photoelectron-induced desorption of hydrogen ions from beryllium, carbon, aluminum, tantalum, and gold surfaces. This report describes the results of the cross-section measurements, and discusses a time-of-flight technique that allows the determination of ionic-desorption cross sections as small as 10/sup -25/ cm/sup 2/ per photoelectron. 19 refs., 7 figs.
Date: September 20, 1985
Creator: Kinney, J. H.; Siekhaus, W. J. & Anderson, R. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of impurities in the Tandem Mirror Experiment using extreme-ultraviolet spectroscopy

Description: Impurities in the Tandem Mirror Experiment (TMX) have been studied using extreme ultraviolet spectroscopy. Three time-resolving absolutely-calibrated normal-incidence monochromators, one on each section of TMX, were used to study the impurity emissions in the wavelength range of 300 A to 1600 A. The instruments on the east end cell and central cell were each capable of obtaining spatially-resolved profiles from 22 chords of the plasma simultaneously while the instrument on the west end cell mon… more
Date: May 12, 1982
Creator: Strand, O. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Proof of concept testing of an integrated dry injection system for SO sub x /NO sub x control

Description: The objectives of the subscale test program were designed to provide sorbent and additive selection guidance, and, in so doing, supply answers to the questions posed in the preceding section. The objectives are: Identify the best commercial hydrate sorbent and the best enhanced hydrate sorbent from a list of nine types, based upon S0{sub 2} removal at Ca/S=2. Determine the relative effectiveness of sodium sesquicarbonate versus sodium bicarbonate for S0{sub 2} and NO{sub x} control over the tem… more
Date: January 1, 1989
Creator: Helfritch, D.J.; Bortz, S.J. (Research-Cottrell, Inc., Somerville, NJ (United States). Environmental Services and Technologies Div.) & Beittel, R. (Riley Stoker Corp., Worcester, MA (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of BEACON technology. Quarterly report, April-June 1982

Description: The BEACON process involves the catalytic deposition of a highly reactive form of carbon from a gas stream which contains carbon monoxide. The carbon-depleted gas is combusted with air to produce power, and the carbon is reacted with steam to produce methane or hydrogen. Experiments were continued this quarter with the objective of improving the carbon deposition efficiency using a Paraho retort off-gas mixture. Analysis has shown that the use of the Paraho off-gas to make hydrogen would be att… more
Date: March 1, 1983
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theoretical study of the structure, energetics, and dynamics of silicon and carbon systems using tight-binding approaches

Description: Semiempirical interatomic potentials are developed for silicon and carbon by modeling the total energy of the system using tight-binding approaches. The parameters of the models were obtained by fitting to results from accurate first-principles Local Density Functional calculations. Applications to the computation of phonons as a function of volume for diamond-structured silicon and carbon and the thermal expansions for silicon and diamond yields results which agree well with experiment. The ph… more
Date: October 25, 1991
Creator: Xu, Chunhui.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Secondary defects in quenched platinum

Description: The structure of secondary defects in two different platinum purities quenched under ultra high vacuum, has been studied by transmission electron microscopy. Faulted loops on (100) planes have been observed in both materials. In the less pure platinum, Pt B (but purer in terms of carbon content), the defects were observed after quenching, whereas in the purest one, Pt A (but less pure in terms of carbon content), the defects were formed after a long annealing. The Burgers vector of the loops fo… more
Date: November 1, 1979
Creator: Perez, M.I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Silicon ingot casting: Heat Exchanger Method (HEM)/multi-wire slicing: Fixed Abrasive Slicing Technique (FAST), Phase IV. Quarterly progress report No. 2, April 1, 1980-June 30, 1980

Description: Silicon ingot size cast by HEM has been extended to 34 cm x 34 cm x 10 cm. A 20 kg ingot has been solidified at 3 kg/hr with no crucible attachment or ingot cracking problems. Another ingot of 26 kg weight has also been solidified. The heat treatment used to develop a graded structure caused cracking on the inside surface of the first large crucibles. The thermal conditions were altered to minimize high gradients and the cracking was eliminated. A high degree of single crystallinity has been ma… more
Date: August 1, 1980
Creator: Schmid, F.; Khattak, C.P. & Basaran, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of erosion and transport of carbon impurity in the TFTR inner bumper limiter region

Description: Carbon sputtering and transport on the TFTR inner graphite bumper limiter is investigated with the impurity transport code REDEP. Analysis is carried out for a series of ohmic discharges in TFTR. Predictions for Z{sub eff} in the core plasma agree well with in-situ experimental measurements. Run-away self-sputtering of carbon is predicted at low densities and high edge plasma temperatures when the limiter surface was purged of deuterium. Surface erosion and deposition is analyzed. In general, r… more
Date: January 1, 1992
Creator: Hua, T. Q. & Brooks, J. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Engineering considerations of the advanced free electron laser facility

Description: The Advanced Free-Electron Laser (AFEL) is being built at Los Alamos inside a large laboratory building. In addition to cost and available space considerations, several engineering issues affected the design of the AFEL and its facility. The 1300-MHz, 20-MeV electron linac required extensive radiation shielding and a short rf-waveguide run. Free-Electron Lasers (FEL) and photocathode-drive laser optics required a clean, constant temperature environment. New environmental, health, and safety (ES… more
Date: January 1, 1991
Creator: Meier, K.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Synchrotron x-ray study of physisorbed films of mixtures of Ar and Xe on graphite

Description: Mixtures of Ar and Xe have been studied in most of the submonolayer region of the phase diagram (T,chi,rho), T = temperature, chi = chemical composition, rho = fraction of a monolayer. The basic feature is a large tendency to form ..sqrt.. 3 x ..sqrt.. 3 commensurate alloys (Kr-like structures), but none of the commensurate nor of the incommensurate structures form a chemically ordered alloy at 11 K. Thus the 2D solid can be thought of as a solid consisting of particles of an average size. This… more
Date: July 1, 1982
Creator: Bohr, J.; Nielsen, M.; McTague, J. P.; Als-Nielsen, J. & Kjaer, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Probing the possibility of a /sup 12/C/sup 13/C abundance gradient from observations of interstellar CH/sup +/

Description: I have performed high signal-to-noise (SN /equals/ 300 to 500) observations of interstellar CH/sup /plus// at Lick Observatory and at CTIO of the reddened, early-type stars HD 183143, HD 24432, and HD 157038 in an effort to probe the existence of a /sup 12/C/sup 13/C abundance gradient in our Galaxy.
Date: September 16, 1987
Creator: Hawkins, I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of BEACON technology. Quarterly report, October-December 1982

Description: The BEACON process involves the catalytic deposition of a highly reactive form of carbon from a gas stream which contains carbon monoxide. The carbon-depleted gas is combusted with air to produce power, and the carbon is reacted with steam to produce methane or hydrogen. During the quarter both SOHIO and TRW worked on catalysts which would suppress methane formation during steaming thus increasing the amount of hydrogen formed. At SOHIO a C77-K2 catalyst promoted with a Class II compound showed… more
Date: April 1, 1983
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sampling and analysis of trace-organic constituents in ambient and workplace air at coal-conversion facilities

Description: A review of the recent literature reveals that current sampling procedures involve the use of glass fiber filters for particulate-sorbed organics and sorbent resins such as Tenax GC and XAD-2 for vapor-phase organics. Ultra trace-organic analysis of air pollutants or particulates may require the collection of a large (1000 to 3000 m/sup 3/) sample by a high volume air sampler. Personal air sampling requires a smaller (approx. = 0.5 m/sup 3/) and a portable collection apparatus. Trapped organic … more
Date: July 1, 1980
Creator: Flotard, R D
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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