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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.
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.
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))
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
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.
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.
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.
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.
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.
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
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
Partner: UNT Libraries Government Documents Department
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Preliminary results from collisions between 3. 2-TeV /sup 16/O and target nuclei of C, Cu, and Au

Description: We have presented preliminary WA80 data from interactions of /sup 16/O with C, Cu, and Au at 60 and 200 GeVnucleon. These have included total charged-particle multiplicity distributions and transverse energy distributions. Ranges of transverse momentum per particle and of possible energy densities were discussed. Some of the unique features of WA80 were stressed. These are: complete coverage of the target rapidity region, complete coverage of charged-particle multiplicity measurement, and measu… more
Date: January 1, 1987
Partner: UNT Libraries Government Documents Department
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Size effects in aerosol particle interactions: the van der Waals potential and collision rates

Description: Three effects which are explicitly dependent on aerosol particle size are identified and discussed. They are focussed about the particle collision rate and how it relates to the properties of the gas, the particle, and the particle's interaction potential energy which play roles in particle-particle collision rates. By incorporating the conduction electronic free path effect for conductors into the frequency-dependent dielectric constants of silver and graphite, particle size effects in th… more
Date: January 1, 1980
Creator: Marlow, W H
Partner: UNT Libraries Government Documents Department
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Near-isotropic petroleum-coke based graphites for high temperature gas-cooled reactor core components

Description: The standard covers procurement requirements for extruded graphite logs, 15 in. (381 mm) or greater in diameter, manufactured with near-isotropic petroleum cokes and coal-tar pitch binders which are candidates or reference materials for replaceable fuel and reflector blocks for High-Temperature Gas-Cooled Reactors (HTGRs). The requirements are designed to produce the degree of lot-to-lot reproducibility which is required to ensure consistent and predictable properties and irradiation performanc… more
Date: October 1, 1977
Partner: UNT Libraries Government Documents Department
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Characterization of carbonaceous materials using extraction with supercritical pentane

Description: The use of carbonaceous adsorbents is limited by irreversible adsorption of some compounds so the use of supercritical pentane as an extracting solvent was examined. Carbon black appeared to be broken down slowly, but continuously, by the penane. To see if other types of carbon behaved similarly, high purity graphite, technical grade graphites, active carbons, and charcoals were examined. The extracts were characterized by uv spectroscopy, packed column chromatography using flame ionization and… more
Date: May 30, 1980
Creator: Fetzer, J.C.; Graham, J.A.; Arrendale, R.R.; Klee, M.S. & Rogers, L.B.
Partner: UNT Libraries Government Documents Department
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Performance of Room Temperature Mercuric Iodide (HgL/sub 2/) Detectors in the Ultra Low Energy X-Ray Region

Description: Performance of room temperature mercuric iodide x-ray spectrometers has been recently improved through new fabrication techniques and further development of low noise associated electronic systems. This progress has extended the range of measurements to the ultra low energy x-ray region at room temperature. This paper reports the study of the effect of contact material on the performance of HgI/sub 2/ detectors in the low energy x-ray region.
Date: January 1, 1980
Creator: Dabrowski, A. J.; Iwanczyk, J. S.; Barton, J. B.; Huth, G. C.; Whited, R.; Ortale, C. et al.
Partner: UNT Libraries Government Documents Department
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Quantitative nondestructive density determinations of very low-density carbon foams

Description: The carbon density and the carbon distribution in low-density foams that were manufactured by a modified salt-replica process were determined by bulk measurements of weight and volume and by x-ray computed tomography (CT). When determining the carbon density, both methods yielded similar results, however, the high spatial resolution of CT was found to yield nondestructive quantitative information on the carbon distribution that was not available from bulk measurements. The highest and lowest fo… more
Date: January 1, 1991
Creator: Moddeman, W. E.; Kramer, D. P.; Firsich, D. W.; Trainer, P. D.; Back, P. S.; Smith, S. D. et al.
Partner: UNT Libraries Government Documents Department
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A novel carbon-based process for flue gas cleanup

Description: The objective of this project is to demonstrate the preliminary technical and economic feasibility of a novel carbon-based process for removal of at least 95% SO{sub 2} and at least 75% NO{sub x} coal combustion flue gas. In the process, flue gas leaving the electrostatic precipitator (ESP) is passed through a trickle bed of achieved carbon catalyst employing a periodic flush of low strength sulfuric acid. The SO{sub 2} is oxidized to SO{sub 3} and removed as medium strength sulfuric acid. The … more
Date: April 1, 1992
Creator: Gangwal, S.K. (Research Triangle Inst., Research Triangle Park, NC (United States)) & Silveston, P.L. (Waterloo Univ., ON (Canada))
Partner: UNT Libraries Government Documents Department
open access

Proof of concept testing of an integrated dry injection system for SO sub x /NO sub x control

Description: The objective 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 temp… more
Date: January 1, 1990
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))
Partner: UNT Libraries Government Documents Department
open access

Considerations for the use of synchrotron radiation sources to measure sub-keV x-ray photoabsorption cross sections in transmission

Description: Sub-keV x-ray photoabsorption cross section measurements in transmission have been made using synchrotron radiation beam lines on the VUV storage ring at the National Synchrotron Light Source (NSLS) and on the SPEAR storage ring at Stanford. The experimental considerations associated with making absolute measurements are reviewed, along with techniques for resolving difficulties. Suggestions for future measurements are included.
Date: February 1, 1988
Creator: Tirsell, K.G. & Del Grande, N.K.
Partner: UNT Libraries Government Documents Department
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