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A PROGRAM OF RESEARCH AND CALCULATIONS OF RESONANCE ABSORPTION. Final Report

Description: A direct numerical integration of the integral equation for the average collision density in the absorber was previously suggested in a discussion of resonance absorption. The implementation of this program is considered. The method of calculation, comparison with experimental data, and the computer code developed are described. The method of integration, computation of cross sections, selection of mesh size, integration interval, outside correction, the Dancoff correction, and unresolved reson… more
Date: August 28, 1961
Creator: Nordheim, L.W.
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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Theoretical analysis of spectral lines of one- and two-electron ions in hot plasmas

Description: We discuss the line shapes for the 1s-2p, 1s-3p and (ls)/sup 2/ - 1s2p, (1s)/sup 2/ - 1s3p absorption lines in hot plasmas. In our model calculations the perturbing ions are considered quasi-static and widths due to collisions with electrons are calculated in the impact approximation. The collective effect of the plasma electrons is accounted for by a self-consistent model or by a simple Debye-Hueckel screening. These models in general predict different line shapes. We present calculations for … more
Date: July 28, 1982
Creator: Rozsnyai, B.F. & Einwohner, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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OPTICAL AND DYNAMIC PROPERTIES OF UNDOPED AND DOPED SEMICONDUCTOR NANOSTRUCTURES

Description: This chapter provides an overview of some recent research activities on the study of optical and dynamic properties of semiconductor nanomaterials. The emphasis is on unique aspects of these properties in nanostructures as compared to bulk materials. Linear, including absorption and luminescence, and nonlinear optical as well as dynamic properties of semiconductor nanoparticles are discussed with focus on their dependence on particle size, shape, and surface characteristics. Both doped and undo… more
Date: September 28, 2007
Creator: Grant, C D & Zhang, J Z
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Partner: UNT Libraries Government Documents Department
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Spectroscopic Characterization of Intermediates in the Iron Catalyzed Activation of Alkanes

Description: The present report begins with a brief survey of recent hypervalent iron chemistry and mentions two previously reported ferrate papers funded by the DOE/BES grant. The focus is then shifted to the seven publications acknowledging support of the grant that have not been reported since the last Progress Report, DOE/ER/14340-9, was prepared. These papers deal with: (a) the successful use of an ATR element in a stopped-flow infrared spectrometer, (b) the rationalization of a depolarization of a LiC… more
Date: May 28, 2007
Creator: Eyring, Edward M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low-level detection and quantification of Plutonium(III, IV, V,and VI) using a liquid core waveguide

Description: Understanding the aqueous chemistry of plutonium, in particular in environmental conditions, is often complicated by plutonium's complex redox chemistry. Because plutonium possesses four oxidation states, all of which can coexist in solution, a reliable method for the identification of these oxidation states is needed. The identification of plutonium oxidation states at low levels in aqueous solution is often accomplished through an indirect determination using series of liquid-liquid extractio… more
Date: June 28, 2003
Creator: Wilson, Richard E.; Hu, Yung-Jin & Nitsche, Heino
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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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Final report for the project "Improving the understanding of surface-atmosphere radiative interactions by mapping surface reflectance over the ARM CART site" (award DE-FG02-02ER63351)

Description: Surface spectral reflectance (albedo) is a fundamental variable affecting the transfer of solar radiation and the Earth’s climate. It determines the proportion of solar energy absorbed by the surface and reflected back to the atmosphere. The International Panel on Climate Change (IPCC) identified surface albedo among key factors influencing climate radiative forcing. Accurate knowledge of surface reflective properties is important for advancing weather forecasting and climate change impact stud… more
Date: November 28, 2008
Creator: Trishchenko, Alexander P.; Luo, Yi; Konstantin V. Khlopenkov, William M. Park; Li, Zhanqing & Cribb, Maureen
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electronic Properties of LiFePO4 and Li doped LiFePO4

Description: The potential use of different iron phosphates as cathodematerials in lithium-ion batteries has recently been investigated.1 Oneof the promising candidates is LiFePO4. This compound has severaladvantages in comparison to the state-of-the-art cathode material incommercial rechargeable lithium batteries. Firstly, it has a hightheoretical capacity (170 mAh/g). Secondly, it occurs as mineraltriphylite in nature and is inexpensive, thermally stable, non-toxic andnon-hygroscopic. However, its low ele… more
Date: June 28, 2005
Creator: Zhuang, G.V.; Allen, J.L.; Ross, P.N.; Guo, J.-H. & Jow, T.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling the absorption of intense, short laser pulses in steep density gradients

Description: A subroutine which calculates the absorption of short pulse electromagnetic radiation in a material has been installed into the laser fusion modeling program called LASNEX. Calculational results show the necessity for NLTE physics to account for ionization, the development of non-exponential density profiles for the expanding plasma and movement of the critical point toward the surface which results in Doppler shifts of the reflected light. Comparison of calculations of local scale lengths with… more
Date: January 28, 1991
Creator: Alley, W.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal stress in the edge cladding of Nova glass laser disks

Description: We calculated thermal stresses in Nova glass laser disks having light-absorbing edge cladding glass attached to the periphery with an epoxy adhesive. Our closed-form solutions indicated that, because the epoxy adhesive is only 25 ..mu..m across, it does not significantly affect the thermal stress in the disk or cladding glass. Our numerical results showed a peak tensile stress in the cladding glass of 24 MPa when the cladding glass had a uniform absorption coefficient of 7.5 cm/sup -1/. This pe… more
Date: September 28, 1987
Creator: Pitts, J. H.; Kong, M. K. & Gerhard, M. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Schlieren observations of density channels in MPPE

Description: Schlieren imaging techniques were used to study the density depressions created by the ATA electron beam 37 cm after the entrance foil. Typical channel depressions were 5--10% of ambient density per pulse. Under IFR guiding channel depths as deep as 30% were seen on single pulse operation. Pulse 5 of the 5 pulse burst has passed through a channel reduced to 30% of ambient density. To lowest order, one would expect channel density depressions to scale as ({Delta}n/n) {proportional to} ({number s… more
Date: September 28, 1990
Creator: Guethlein, G. (Lawrence Livermore National Lab., CA (USA)) & Pechacek, B. (Naval Research Lab., Washington, DC (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Bubbles and their implications for laser-fusion

Description: Bubbles are concentrations of electromagnetic energy in the region of the critical density that force out the plasma to form a void. Since the critical density surface is cratered, absorption may be greater than a smooth surface since a larger area will be available for absorption and the reflected light will have a large probability of restriking the critical density. The distance between bubbles is several wavelengths and consequently they may encourage Rayleigh--Taylor instabilities. The thr… more
Date: October 28, 1975
Creator: Estabrook, K. G. & Valeo, E. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Instruction manual for Gunn-diode microwave cavity ammonia monitor

Description: The Gunn-diode microwave cavity instrument is a self-contained (the vacuum pump is external) microwave spectrometer for the specific detection and monitoring of ammonia gas in air. A solid state microwave source is used together with a high-Q resonant microwave cavity which is both the frequency selecting device for the source and the sample container through which the sampled gases pass. The ammonia absorption transition at 23,870.1 MHz is monitored continuously with this instrument. The monit… more
Date: June 28, 1977
Creator: Hrubesh, L. W.; Maddux, A. S. Jr. & Johnson, D. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Corrosion Resistance of Amorphous Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4 coating - a new criticality-controlled material

Description: An iron-based amorphous metal with good corrosion resistance and a high absorption cross-section for thermal neutrons has been developed and is reported here. This amorphous alloy has the approximate formula Fe{sub 49.7}Cr{sub 17.7}Mn{sub 1.9}Mo{sub 7.4}W{sub 1.6}B{sub 15.2}C{sub 3.8}Si{sub 2.4} and is known as SAM2X5. Chromium (Cr), molybdenum (Mo) and tungsten (W) were added to provide corrosion resistance, while boron (B) was added to promote glass formation and the absorption of thermal neu… more
Date: March 28, 2007
Creator: Farmer, J C; Choi, J S; Saw, C K; Rebak, R; Day, S D; Lian, T et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Isolation and Propterties of Curium

Description: The isolation of curium, element number 96, in relatively pure form has been accomplished. A method, involving a solvent extraction process, is given for the purification of americium from lanthanum and other ions. The discovery of a higher oxidation state of americium led to a method of separating americium from curium. Separation of the two elements was also accomplished by use of ion exchange resins. The details of the isolation of curium are given; the results of the spectrographic analysis… more
Date: July 28, 1948
Creator: Werner, L.B. & Perlman, I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Heavy Ion Inertial Fusion Energy: Summaries of Program Elements

Description: The goal of the Heavy Ion Fusion (HIF) Program is to apply high-current accelerator technology to IFE power production. Ion beams of mass {approx}100 amu and kinetic energy {>=} 1 GeV provide efficient energy coupling into matter, and HIF enjoys R&D-supported favorable attributes of: (1) the driver, projected to be robust and efficient; see 'Heavy Ion Accelerator Drivers.'; (2) the targets, which span a continuum from full direct to full indirect drive (and perhaps fast ignition), and ha… more
Date: February 28, 2011
Creator: Friedman, A; Barnard, J J; Kaganovich, I; Seidl, P A; Briggs, R J; Faltens, A et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of New Optical Sensors for Measurements of Mercury Concentrations, Speciation, and Chemistry

Description: A diode-laser-based ultraviolet absorption sensor for elemental mercury was developed and applied for measurements in a high-temperature flow reactor and in the exhaust stream of a coal-fired combustor. The final version of the sensor incorporates a 375-nm single-mode laser and a 784-nm distributed feedback (DFB) laser. The output of these lasers is sum-frequency mixed in a non-linear beta-barium borate crystal to generate a 254-nm beam. By tuning the frequency of the DFB laser, the ultraviolet… more
Date: September 28, 2008
Creator: Lucht, Robert
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the Putative Detection of Z>0 X-Ray Absorption Features in the Spectrum of Mrk 421

Description: In a series of papers, Nicastro et al. have claimed the detection of z > 0 O VII absorption features in the spectrum of Mrk 421 obtained with the Chandra Low Energy Transmission Grating Spectrometer (LETGS). We evaluate those claims in the context of a high quality spectrum of the same source obtained with the Reflection Grating Spectrometer (RGS) on XMM-Newton. The data comprise over 955 ksec of usable exposure time and more than 2.6 x 10{sup 4} counts per 50 m{angstrom} at 21.6 {angstrom}.… more
Date: April 28, 2006
Creator: Rasmussen, Andrew P.; /SLAC /KIPAC, Menlo Park; Kahn, Steven M.; /SLAC /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Paerels, Frits; /Columbia U., Astron. Astrophys. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The O VII X-Ray Forest Toward Markarian 421: Consistency between XMM-Newton and Chandra

Description: Recently the first detections of highly ionized gas associated with two Warm-Hot Intergalactic Medium (WHIM) filaments have been reported. The evidence is based on X-ray absorption lines due to O VII and other ions observed by Chandra towards the bright blazar Mrk 421. We investigate the robustness of this detection by a re-analysis of the original Chandra LETGS spectra, the analysis of a large set of XMM-Newton RGS spectra of Mrk 421, and additional Chandra observations. We address the reliabi… more
Date: April 28, 2006
Creator: Kaastra, J. S.; Werner, N.; den Herder, J. W. A.; /SRON, Utrecht; Paerels, F. B. S.; /Columbia U., Astron. Astrophys. et al.
Item Type: Refine your search to only Report
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 pilot plant data have been reconciled using 17% inlet CO{sub 2}. A rate-based model demonstrates that the stripper is primarily controlled by liquid film mast transfer resistance, with kinetics at vacuum and diffusion of reactants and products at normal pressure. An additional major unknown ion… more
Date: July 28, 2006
Creator: Rochelle, Gary T.; Chen, Eric; Oyenekan, Babatunde; Sexton, Andrew; Davis, Jason; Hilliard, Marcus et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Completion of Kr-81 and Kr-85 Analysis Development for Hydrogeology and Testing its Validity by Assessing Aquifer Recharge Rates

Description: Summary The overall objective was to complete the development of a RIMS-based analytical technique to determine the concentration of the rare krypton radioisotopes, 81Kr and 85Kr, in samples of interest to the geoscience and planetary science community The key to RIMS is the use of tunable lasers to selectively and efficiently excite by resonant photon absorption atomic states unique to the chosen element. Ionization of the specified element can then occur while excluding all other constituents… more
Date: April 28, 2007
Creator: Thonnard, Norbert
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photoelectron Emission Studies in CsBr at 257 nm

Description: CsBr/Cr photocathodes were found [1,2] to meet the requirements of a multi-electron beam lithography system operating with a light energy of 4.8 eV (257nm). The fact that photoemission was observed with a light energy below the reported 7.3 eV band gap for CsBr was not understood. This paper presents experimental results on the presence of intra-band gap absorption sites (IBAS) in CsBr thin film photo electron emitters, and presents a model based on IBAS to explain the observed photoelectron em… more
Date: September 28, 2006
Creator: Maldonado, Juan R.; Liu, Zhi; Sun, Yun; Pianetta, Piero A.; Pease, Fabian W. & /Stanford U., Elect. Eng. Dept. /SLAC, SSRL
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SYNCHROTRON X-RAY BASED CHARACTERIZATION OF CDZNTE CRYSTALS

Description: Synthetic CdZnTe or 'CZT' crystals can be used for the room temperature-based detection of {gamma}-radiation. Structural/morphological heterogeneities within CZT, such as twinning, inclusions, and polycrystallinity can affect detector performance. We used a synchrotron-based X-ray technique, specifically extended X-ray absorption fine-structure (EXAFS) spectroscopy, to determine whether there are differences on a local structural level between intact CZT of high and low radiation detector perfo… more
Date: September 28, 2006
Creator: Duff, M
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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