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Impurity studies in fusion devices using laser-fluorescence-spectroscopy

Description: Resonance fluorescence excitation of neutral atoms using tunable radiation from dye lasers offers a number of unique advantages for impurity studies in fusion devices. Using this technique, it is possible to perform local, time-resolved measurements of the densities and velocity distributions of metallic impurities in fusion devices without disturbing the plasma. Velocities are measured by monitoring the fluorescence intensity while tuning narrow bandwidth laser radiation through the Doppler - … more
Date: August 1, 1980
Creator: Husinsky, W.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Low-temperature photoluminescence of detector-grade JgO/sub 2/

Description: The low-temperature photoluminescence of HgI/sub 2/ is reported. Three main luminescence bands are observed, with peaks at approx. 2.30, 2.20, and 2.00 eV at 77K. At 4.2K, the highest energy peak shows considerable structure. The temperature dependence of these lines indicates both free and bound exciton recombination, and very small exciton binding energies (approx. 3 to 4 meV) have been estimated. A comparison of the results of sublimation and doping experiments suggests that the lowest energ… more
Date: January 1, 1982
Creator: Wu, Z. L.; Merz, J. L.; van den Berg, L. & Schnepple, W. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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On-line composition with laser-based techniques

Description: Current methods for determining the composition of coal gasification streams generally involve sampling, some treatment, and inherent delay times prior to analysis. Optical instrumentation, on the other hand, provides the potential for on-line, rapid-response monitoring of gasifier streams. Among the optical technques that appear quite promising for this application are coherent anti-Stokes Raman scattering (CARS), laser-induced breakdown spectroscopy (LIBS), Fourier transform infrared spectros… more
Date: January 1, 1982
Creator: Finch, F.T. & Hartford, A. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Combustion Research Program: Flame studies, laser diagnostics, and chemical kinetics

Description: We have made a detailed study of the care that must be taken to correctly measure OH radical concentrations in flames. A large part of these studies has concerned collisional quenching of hydride radical species (OH, NH, and NH{sub 2}), in particular the dependence upon rotational level and collision velocity (temperature). The results on OH and NH have shown unique and interesting behavior from the viewpoint of fundamental molecular dynamics, pointing to quenching often governed by collisions … more
Date: January 22, 1991
Creator: Crosley, D.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Vibrational relaxation of matrix-isolated CH/sub 3/F and HCl

Description: Kinetic and spectroscopic studies have been performed on CH/sub 3/F and HCl as a function of host matrix and temperature. Temporally and spectrally resolved infrared fluorescence was used to monitor the populations of both the initially excited state and the lower lying levels which participate in the relaxation process. For CH/sub 3/F, relaxation from any of the levels near 3.5 ..mu.., i.e. the CH stretching fundamentals or bend overtones, occurs via rapid (< 5 ns) V ..-->.. V transfer to 2..n… more
Date: August 1, 1981
Creator: Young, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spectroscopic probes of vibrationally excited molecules at chemically significant energies

Description: These experiments apply multiple-laser spectroscopic techniques to investigate the bond energies, potential surface topologies, and dissociation dynamics of highly vibrationally excited molecules. Infrared-optical double resonance pumping of light atom stretch vibrations in H{sub 2}O{sub 2} and HN{sub 3} prepares reactant molecules in single rovibrational states above the unimolecular dissociation threshold on the ground potential surface, and laser induced fluorescence detection of the OH or N… more
Date: March 1, 1992
Creator: Rizzo, T.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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New generation of monitors for PAH&#x27;s from synthetic fuel production

Description: A gap exists between the crude techniques available for measuring polynuclear aromatic (PNA) compounds in the workplace, and the sophisticated analytical tools used in the laboratory for a much more complete characterization of pollutants from synfuel operations such as coal, tar sand, and oil shale processing. Real-time or near-real instruments suitable for use by industrial hygienists are urgently needed to measure fugitive emissions. Several new instruments and instrumental techniques are de… more
Date: January 1, 1977
Creator: Gammage, R B; Vo-Dinh, T; Hawthorne, A R; Thorngate, J H & Parkinson, W W
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of fluorescent particle tracer data

Description: Four fluorescent particle tracer experiments were conducted during the July 1979 ASCOT experiment in the Anderson Creek Valley of northern California. The purpose of the experiment was to examine the transport and elongation of a plume traveling in the Anderson Creek nocturnal drainage flow and investigate the interaction of the Anderson Creek and Putah Creek flow fields. Sequential samples of tracer material at three downwind locations in Anderson Creek gave effective transport velocities of 1… more
Date: January 1, 1980
Creator: Clements, W.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Amorphous thin films for solar-cell applications. Final report, September 11, 1978-September 10, 1979

Description: In Section II, Theoretical Modeling, theories for the capture of electrons by deep centers in hydrogenated amorphous silicon (a-Si:H) and for field-dependent quantum efficiency in a-Si:H are presented. In Section III, Deposition and Doping Studies, the optimization of phosphorus-doped a-Si:H carried out in four different discharge systems is described. Some details of the dc proximity and rf magnetron discharge systems are also provided. Preliminary mass spectroscopy studies of the rf magnetron… more
Date: February 1, 1980
Creator: Carlson, D. E.; Balberg, I.; Crandall, R. S.; Goldstein, B. C.; Hanak, J. J.; Pankove, J. I. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiation Laboratory, University of Notre Dame. Quarterly report, July 1, 1977--September 30, 1977. [Short summaries of progress in 27 projects]

Description: Status of the following investigations is given: effect of molecular geometry on the electron affinity of H/sub 2/O; effect of non-spherically symmetric exchange potential in energy transfer and CIDEP; fragmentation patterns in the radiolysis of normal alkanes; properties of solvated electrons; temperature dependence of electron localization and impurity trapping in methanol and propanol; field-dependent electron mobility; aluminium cluster and organoaluminum systems; collision-induced atomic d… more
Date: October 13, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Picosecond spectroscopic search for electron transfer reactions in dimeric and trimeric reaction center models containing pyrochlorophyll/sub a/

Description: To further understanding of the light driven electron transfer reactions found in natural photosystems, dimeric and trimeric model molecules containing PChl/sub a/ were studied. The potential donor and acceptor subunits were covalently linked to form a single large molecule. The distance between the donor and acceptor subunits was altered by using both 10 atom and 5 atom chains. The effects of altering the relative orientation of the donor and acceptor were probed by contrasting the kinetics ob… more
Date: January 1, 1980
Creator: Netzel, T L; Bucks, R R; Boxer, S G & Fujita, I
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stress and phase transformation phenomena in oxide films

Description: In situ optical methods are reviewed for characterization of phase transformation processes and evaluation of residual stress in solution- deposited metastable oxide films. Such low density films most often are deposited as disordered phases making them prone to crystallization and attendant densification when subjected to increased temperature and/or applied pressure. Inherent stress imparted during film deposition and its evolution during the transformation are evaluated from phonon frequency… more
Date: April 1, 1992
Creator: Exarhos, G.J. & Hess, N.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quarterly report, 1 January-31 March 1980

Description: Progress is reported in the following areas of research: characterization of organic pollutants emitted by fossil fuel processing and energy generating plants; environmental effects of using municipal solid wastes as a supplementary fuel; microbiological air quality at the Ames Municipal Solid Waste Recovery System; solid waste to methane environmental study; x-ray and ultraviolet excited optical luminescence (XEOL, UVEOL) of carcinogens - analytical possibilities; laser pumped luminescence (LP… more
Date: May 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Review of high bandwidth fiber optics radiation sensors

Description: This paper summarizes the use of fiber optics or guided optical systems for radiation sensors. It is limited a passive systems wherein electrical is not required at the sensor location. However, electrically powered light sources, receivers and/or recorders may still be required for detection and data storage in sensor system operation. This paper emphasizes sensor technologies that permit high bandwidth measurements of transient radiation levels, and will also discuss several low bandwidth app… more
Date: January 1, 1985
Creator: Lyons, P. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Remote detection of atmospherically dispersed vegetative cells using fluorescence LIDAR

Description: A uv fluorescence LIDAR system is employed for the long range detectio of atmospherically dispersed biological particles (e.g. Bacillus thuringiensis) released from an aerosol generator. 1 ref., 2 figs.
Date: January 1, 1991
Creator: Tiee, J. J.; Eichinger, W. E.; Hof, D. E.; Holtkamp, D. B.; Karl, R. R. Jr.; Martinez, R. J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quarterly report, 1 October-31 December 1979

Description: Progress is reported in the following areas of research: characterization of organic pollutants emitted by fossil fuel processing and energy generating plants; environmental effects of using municipal solid wastes as a supplementary fuel; microbiological air quality at the Ames Municipal Solid Waste Recovery System; solid waste to methane environmental study; x-ray and ultraviolet excited optical luminescence (XEOL, UVEOL) of carcinogens - analytical possibilities; laser pumped luminescence (LP… more
Date: March 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Influence of phase boundaries on photo-induced electron transfer reactions. Final report, July 1, 1977-August 31, 1979

Description: A summary is presented of results of research which was conducted on bipyridyl complexes of ruthenium, with the objective of storing visible light energy. The research covered analytical techniques, synthesis, properties of Ru complexes in monolayers and micelles, and luminescence quenching. 23 references. (DLC)
Date: August 1, 1979
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Discharge excitation of the XeF C to A transition

Description: Recent success in high efficiency and high energy laser extraction of tunable radiation in the blue-green C-A transition of XeF under intense, short-pulse electron beam excitation has renewed interest in the possibility of similar performance in avalanche discharges. We present preliminary results of discharge excited fluorescence studies in a variety of devices having different degrees of energy loading.
Date: January 1, 1987
Creator: Sze, R. C.; Greene, D. P.; Bigio, I. J.; Shay, T. M.; McCown, A. W.; Figueira, J. F. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of luminescent bacteria as tracers for geological reservoir characterization

Description: This research project resulted from recognizing the problem of being unable to accurately distinguish communication between wells in producing oil zones which may or may not be continuous. Such a determination is necessary when considering Enhanced Oil Recovery (EOR) whether it is water flooding, carbon dioxide, or other methods which increase the sweep efficiency. Various kinds of chemical tracers are available, but they are expensive and many might be considered hazardous for underground aqui… more
Date: January 1, 1991
Creator: King, J.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Oak Ridge National Laboratory Review: Volume 24, Nos. 3 and 4, 1991

Description: Oak Ridge National Laboratory (ORNL) is a multiprogram, multipurpose laboratory that conducts research in the physical, chemical, and life sciences; in fusion, fission, and fossil energy; and in energy conservation and other energy-related technologies. This review contains articles on chemical extraction techniques, electron transport in gases and liquids, diamond films, the contribution of fossil fuels to the greenhouse effect, various sensors for safety applications, and temperature measurem… more
Date: January 1, 1991
Creator: Krause, C. (ed.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Amorphous thin films for solar-cell applications. Quarterly report No. 1, 11 September-10 December 1979

Description: Research progress on amorphous Si:H solar cells is described. Tasks include theoretical modeling, deposition and doping studies, experimental characterization of a-Si:H, formation of solar cell structures, and evaluation of solar cell parameters. A new method for determining the drift mobility of majority carriers in doped a-Si:H is discussed. Deposition and doping studies have been performed in an rf magnetron discharge system. Mass spectroscopy has been used to show that the major impurities … more
Date: December 1, 1979
Creator: Carlson, D. E.; Crandall, R. S.; Dresner, J.; Goldstein, B.; Hanak, J. J.; Moore, A. R. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigations of glass structure using fluorescence line narrowing and moleuclar dynamics simulations

Description: The local structure at individual ion sites in simple and multicomponent glasses is simulated using methods of molecular dynamics. Computer simulations of fluoroberyllate glasses predict a range of ion separations and coordination numbers that increases with increasing complexity of the glass composition. This occurs at both glass forming and glass modifying cation sites. Laser-induced fluorescence line-narrowing techniques provide a unique probe of the local environments of selected subsets of… more
Date: July 2, 1982
Creator: Weber, M. J. & Brawer, S. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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