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Excited state absorption measurements of Sm sup 2+ in CaF sub 2 , SrF sub 2 , and SrCl sub 2

Description: We measured the pump-probe spectrum of the Sm{sup 2+} ion in three materials: CaF{sub 2}, SrF{sub 2}, and SrCl{sub 2}. The onset of the observed prominent excited-state absorption band is consistent with an electrostatic model for impurity levels in a solid-state material. 15 refs., 4 figs., 1 tab.
Date: April 1, 1991
Creator: Lawson, J. K.; Lee, H. W. H.; Payne, S. A. (Lawrence Livermore National Lab., CA (United States)) & Boatner, L. A. (Oak Ridge National Lab., TN (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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STEAM-COOLED POWER REACTOR EVALUATION, STEAM-COOLED FAST BREEDER REACTOR

Description: Conceptual design and economic studies of a steamcooled fast breeder reactor that can also be used as a source of power are presented. Two reactor plant sizes were considered: a 300-Mw(e) central power station plant and a 40 Mw(e) plant. It was concluded that attractive economics and good breeding characteristics breeding ratios from 1.27 to 1.42) can be achieved in steam- cooled PuO/sub 2/UO/sub 2/ fueled fast reactors. Low capital costs can be obtained by a compact reactor core and the absenc… more
Date: April 15, 1961
Creator: Sofer, G.; Hankel, R.; Goldstein, L. & Birman, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Resonators for heavily beam-loaded linacs

Description: Capacitively loaded resonant line section accelerating structures are discussed. Prototype models were measured at low levels, and calculations were made to predict high level operation. High current composite beams of multiple-beamlets as accelerated by a MEQALAC were assumed.
Date: April 28, 1980
Creator: Sanders, R.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Selective solvent absorption in coal conversion

Description: The objectives of this project are: (1) to determine the importance of the presence of added hydrogen donor compounds within the coal in the first stage of direct liquefaction processes; and (2) to determine the composition of the solvent absorbed by and present within the coal in the first stage of direct coal liquefaction.
Date: April 1, 1992
Creator: Larsen, J. W.; Lapucha, A.; Lazarov, L. & Amui, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Emission cross sections and energy extraction for the mid-infrared transitions of Er, Tm, and Ho in oxide and fluoride crystals

Description: Emission cross sections have been measured for the transitions between the two lowest spin orbit multiplets of Er, Tm, and Ho in several fluoride and oxide crystals. Properties affecting energy extraction efficiency are summarized and pulsed extraction performance is calculated for several of these quasi-three-level laser media. 4 refs., 9 figs.
Date: April 1, 1991
Creator: Chase, L. L.; Payne, S. A.; Smith, L. K.; Kway, W. L. & Krupke, W. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Synthesis, evaluation and defect compensation of tetrahedral glasses as possible solar cell materials. Final report, February 1, 1979-April 30, 1980

Description: The work reported was directed towards evaluation of new amorphous compounds for application in solar cells. The ternary A/sup II/B/sup IV/C/sub 2//sup V/ chalcopyrite systems were selected because of their inexpensive constituent elements and tetrahedral geometry. Polycrystalline samples of the ternary arsenides with Cd and Zn as the group II element and Ge, Si, Sn as the group IV element were synthesized. Thin films were deposited by vacuum evaporation of the bulk ternary arsenides. The stoic… more
Date: April 1, 1980
Creator: Rauh, R. D.; Rose, T. L. & Scoville, A. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Uptake by plants of radionuclides from FUSRAP waste materials

Description: Radionuclides from FUSRAP wastes potentially may be taken up by plants during remedial action activities and permanent near-surface burial of contaminated materials. In order to better understand the propensity of radionuclides to accumulate in plant tissue, soil and plant factors influencing the uptake and accumulation of radionuclides by plants are reviewed. In addition, data describing the uptake of the principal radionuclides present in FUSRAP wastes (uranium-238, thorium-230, radium-226, l… more
Date: April 1, 1983
Creator: Knight, M.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pion absorption processes. [32 to 74 MeV]

Description: Proton and deuteron production from low-energy pion absorption in light nuclei leading to discrete and continuum states were measured. The LEP beam line at LAMPF was used with a stack of 8 intrinsic germanium crystals. The proton energy spectra are in general characterized by a broad bump at an energy approximately corresponding to ..pi../sup +/d ..-->.. pp reaction kinematics, suggestive of pion absorption on 2 nucleons. The energy-integrated cross-section for production of deuterons has an an… more
Date: April 1, 1980
Creator: Doss, K G.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spatially resolved localized vibrational mode spectroscopy of carbon in liquid encapsulated Czochralski grown gallium arsenide wafers

Description: Substitutional carbon on an arsenic lattice site is the shallowest and one of the most dominant acceptors in semi-insulating Liquid Encapsulated Czochralski (LEC) GaAs. However, the role of this acceptor in determining the well known W'' shape spatial variation of neutral EL2 concentration along the diameter of a LEC wafer is not known. In this thesis, we attempt to clarify the issue of the carbon acceptor's effect on this W'' shaped variation by measuring spatial profiles of this acceptor alon… more
Date: April 1, 1988
Creator: Yau, Waifan.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rare gas halide lasers for fusion. Final technical report, 1 March 1979-29 February 1980

Description: In an effort to reliably extend the understanding of KrF* lasers, we collected specific, detailed experimental data and carried out theoretical calculations to explore and document those issues we identified as likely to be important in the short pulse operating regime. These included the effects of: (1) fuel burnup, (2) electron quenching, (3) gain/absorption at high current densities, (4) photoionization, (5) accessibility of the lying levels of KrF by laser flux, (6) temperature on fluoresce… more
Date: April 1, 1980
Creator: Duzy, C.; Hsia, J.; Hyman, H.; Jacob, J.; Klimek, D.; Parks, J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Guide to Savannah River Laboratory Analytical Services Group

Description: The mission of the Analytical Services Group (ASG) is to provide analytical support for Savannah River Laboratory Research and Development Programs using onsite and offsite analytical labs as resources. A second mission is to provide Savannah River Site (SRS) operations with analytical support for nonroutine material characterization or special chemical analyses. The ASG provides backup support for the SRS process control labs as necessary.
Date: April 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of a computer model for polycrystalline thin-film CuInSe sub 2 and CdTe solar cells

Description: This report describes work to develop a highly accurate numerical model for CuInSe{sub 2} and CdTe solar cells. ADEPT (A Device Emulation Program and Toolbox), a one-dimensional semiconductor device simulation code developed at Purdue University, was used as the basis of this model. An additional objective was to use ADEPT to analyze the performance of existing and proposed CuInSe{sub 2} and CdTe solar cell structures. The work is being performed in two phases. The first phase involved collecti… more
Date: April 1, 1992
Creator: Gray, J.L.; Schwartz, R.J. & Lee, Y.J. (Purdue Univ., Lafayette, IN (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Frustrated spin correlations in diluted spin ice Ho2-xLaxTi2O7

Description: We have studied the evolution of the structural properties as well as the static and dynamic spin correlations of spin ice Ho2Ti2O7, where Ho was partially replaced by non-magnetic La. The crystal structure of diluted samples Ho2-xLaxTi2O7 was characterized by x-ray and neutron diffraction and by Ho L-III-edge and Ti K-edge extended x-ray absorption fine structure (EXAFS) measurements. It is found that the pyrochlore structure remains intact until about x = 0.3, but a systematic increase in loc… more
Date: April 30, 2008
Creator: Ehlers, Georg; Ehlers, G.; Mamontov, E.; Zamponi, M.; Faraone, A.; Qiu, Y. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Structure, Magnetism, and Transport of CuCr2Se4 Thin Films

Description: We report the successful growth of highly spin-polarized chalcogenide thin films of CuCr{sub 2}Se{sub 4}, which are promising candidates for spin-based electronic applications. We also present electronic structure calculations for CuCr{sub 2}Se{sub 4} that, together with magnetic and transport data, imply that the stoichiometric compound is a metallic ferromagnet with a relatively low density of hole-like carriers at the Fermi energy. These calculations also predict that a deficiency of Se will… more
Date: April 1, 2007
Creator: Bettinger, J. S.; Chopdekar, R. V.; Liberati, M.; Neulinger, J. R.; Chshiev, M.; Takamura, Y. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characterization of chemical bonding in low-k dielectric materialsfor interconnect isolation: a xas and eels study

Description: The use of low dielectric constant materials in the on-chipinterconnect process reduces interconnect delay, power dissipation andcrosstalk noise. To achieve the requirements of the ITRS for 2007-2009minimal sidewall damage from etch, ash or cleans is required. In chemicalvapor deposited (CVD) organo-silicate glass (OSG) which are used asintermetal dielectric (IMD) materials the substitution of oxygen in SiO2by methyl groups (-CH3) reduces the permittivity significantly (from 4.0in SiO2 to 2.6-3… more
Date: April 10, 2006
Creator: Hoffmann, P.; Schmeisser, D.; Engelmann, H. J.; Zschech, E.; Stegmann, H.; Himpsel, F. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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THERMODYNAMICS OF LIGHT EMISSION AND FREE-ENERGY STORAGE INPHOTOSYNTHESIS

Description: A Planck law relationship between absorption and emission spectra is used to compute the fluorescence spectra of some photosynthetic systems from their absorption spectra. Calculated luminescence spectra of purple bacteria agree well but not perfectly with published experimental spectra. Application of the Planck law relation to published activation spectra for Systems I and II of spinach chloroplast permits independent calculation of the luminescence spectra of the two systems; if the luminesc… more
Date: April 1, 1967
Creator: Ross, Robert T. & Calvin, Melvin
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Accelerator mass spectrometry for quantitative in vivo tracing

Description: Accelerator mass spectrometry (AMS) counts individual rare, usually radio-, isotopes such as radiocarbon at high efficiency and specificity in milligram-sized samples. AMS traces very low chemical doses ({micro}g) and radiative doses (100 Bq) of isotope labeled compounds in animal models and directly in humans for pharmaceutical, nutritional, or toxicological research. Absorption, metabolism, distribution, binding, and elimination are all quantifiable with high precision after appropriate sampl… more
Date: April 19, 2005
Creator: Vogel, J S
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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CO2 Capture by Absorption with Potassium Carbonate

Description: The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. The final campaign of the pilot plant was completed in February 2006 with 5m K{sup +}/2.5m PZ and 6.4m K{sup +}/1.6m PZ using Flexipac AQ Style 20. The new cross-exchanger reduced the approach temperature to less than 9 C. Stripper modeling has demonstrated that a configuration with a ''Flashing Fe… more
Date: April 28, 2006
Creator: Rochelle, Gary T.; Chen, Eric; Oyenekan, Babatunde; Sexton, Andrew & Veawab, Amorvadee
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemical Bonding and Structural Information of Black Carbon Reference Materials and Individual Carbonaceous Atmospheric Aerosols

Description: The carbon-to-oxygen ratios and graphitic nature of a rangeof black carbon standard reference materials (BC SRMs), high molecularmass humic-like substances (HULIS) and atmospheric particles are examinedusing scanning transmission X-ray microscopy (STXM) coupled with nearedge X-ray absorption fine structure (NEXAFS) spectroscopy. UsingSTXM/NEXAFS, individual particles with diameter>100 nm are studied,thus the diversity of atmospheric particles collected during a variety offield missions is asses… more
Date: April 25, 2007
Creator: Hopkins, Rebecca J.; Tivanski, Alexei V.; Marten, Bryan D. & Gilles, Mary K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Understanding the anomalous dispersion of doubly-ionized carbon plasmas near 47 nm

Description: Over the last several years we have predicted and observed plasmas with an index of refraction greater than one in the soft X-ray regime. These plasmas are usually a few times ionized and have ranged from low-Z carbon plasmas to mid-Z tin plasmas. Our main calculational tool has been the average atom code. We have recently observed C{sup 2+} plasmas with an index of refraction greater than one at a wavelength of 46.9 nm (26.44 eV). In this paper we compare the average atom method, AVATOMKG, aga… more
Date: April 15, 2008
Creator: Nilsen, J.; Castor, J. I.; Iglesias, C. A.; Cheng, K. T.; Dunn, J.; Johnson, W. R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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ECH on the MTX (Microwave Tokamak Experiment)

Description: The Microwave Tokamak Experiment (MTX) at LLNL is investigating the heating of high density Tokamak plasmas using an intense pulse FEL. Our first experiments, now beginning, will study the absorption and plasma heating of single FEL pulses (20 ns pulse length and peak power up to 2 GW) at a frequency of 140 GHz. A later phase of experiments also at 140 GHz will study FEL heating at 5 kHz rate for a pulse train up to 50 pulses (35 ns pulse length and peak power up to 4 GW). Future operations are… more
Date: April 1, 1989
Creator: Stallard, B. W.; Byers, J. A.; Hooper, E. B.; Makowski, M. A.; Meassick, S.; Rice, B. W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Luminescent solar concentrator development: Final subcontract report, 1 June 1982-31 December 1984

Description: An investigation of luminescent solar concentrators (LSCs) was begun by the US Department of Energy (DOE) at Owens-Illinois, Inc., in 1978. Experimental and theoretical results of that investigation are summarized in this report. An assessment of the LSC technology was compiled to provide a concise description to guide future research in this field. Since 1978, tremendous progress was made in the development of this device as a practical nonimaging concentrator for achieving solar concentration… more
Date: April 1, 1987
Creator: Friedman, P.S. & Parent, C.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ICRF heating and wave generation in the ATC tokamak. Part 1: wave generation, propagation and absorption

Description: Experimental results and their theoretical interpretations of rf heating experiments in the ion cyclotron range of frequencies are presented. The presentation is in two parts, with this part describing the experimental facilities and characteristics of fast compressional Alfven waves in the tokamak, and a subsequent paper which will deal with the pricipal heating results. It is shown that a simple coupling structure which consists essentially of a semi-circular metal strip and a pair of bumper … more
Date: April 1, 1979
Creator: Takahashi, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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