National Library of Energy BETA

Sample records for absorption fine structure

  1. Speciation of Lead in a Mixed Soil Component System Using X-ray Absorption Fine Structure Spectroscopy

    E-Print Network [OSTI]

    Sparks, Donald L.

    Speciation of Lead in a Mixed Soil Component System Using X-ray Absorption Fine Structure (XAFS). Lead concentrations of 6000, 18000, and 29000 µg Pb/g solid were reacted with soil components

  2. Temperature dependence of the Pd [ital K]-edge extended x-ray-absorption fine structure of PdC[sub [ital x

    SciTech Connect (OSTI)

    McCaulley, J.A. (Hoechst Celanese Research Division, Robert L. Mitchell Technical Center, 86 Morris Avenue, Summit, New Jersey 07901 (United States))

    1993-03-01

    Pd [ital K]-edge extended x-ray-absorption fine-structure (EXAFS) and x-ray-absorption near-edge-structure (XANES) measurements were performed on a Pd carbide phase, PdC[sub [ital x

  3. Near-Edge X-Ray Absorption Fine Structure Spectroscopy of Diamondoid Thiol Monolayers on Gold

    SciTech Connect (OSTI)

    Willey, T.M.; Fabbri, J.D.; Lee, J.R.I.; Schreiner, P.R.; Fokin, A.A.; Tkachenko, B.A.; Fokina, N.A.; Dahl, J.E.P.; Carlson, R.M.K.; Vance, A.L.; Yang, W.; Terminello, L.J.; Buuren, T.van; Melosh, N.A.

    2009-05-26

    Diamondoids, hydrocarbon molecules with cubic-diamond-cage structures, have unique properties with potential value for nanotechnology. The availability and ability to selectively functionalize this special class of nanodiamond materials opens new possibilities for surface modification, for high-efficiency field emitters in molecular electronics, as seed crystals for diamond growth, or as robust mechanical coatings. The properties of self-assembled monolayers (SAMs) of diamondoids are thus of fundamental interest for a variety of emerging applications. This paper presents the effects of thiol substitution position and polymantane order on diamondoid SAMs on gold using near-edge X-ray absorption fine structure spectroscopy (NEXAFS) and X-ray photoelectron spectroscopy (XPS). A framework to determine both molecular tilt and twist through NEXAFS is presented and reveals highly ordered diamondoid SAMs, with the molecular orientation controlled by the thiol location. C 1s and S 2p binding energies are lower in adamantane thiol than alkane thiols on gold by 0.67 {+-} 0.05 and 0.16 {+-} 0.04 eV, respectively. These binding energies vary with diamondoid monolayer structure and thiol substitution position, consistent with different degrees of steric strain and electronic interaction with the substrate. This work demonstrates control over the assembly, in particular the orientational and electronic structure, providing a flexible design of surface properties with this exciting new class of diamond nanoparticles.

  4. Near-Edge X-ray Absorption Fine Structure Spectroscopy of Diamondoid Thiol Monolayers on Gold

    SciTech Connect (OSTI)

    Willey, T M; Fabbri, J; Lee, J I; Schreiner, P; Fokin, A A; Tkachenko, B A; Fokina, N A; Dahl, J; Carlson, B; Vance, A L; Yang, W; Terminello, L J; van Buuren, T; Melosh, N

    2007-11-27

    Diamondoids, hydrocarbon molecules with cubic-diamond-cage structures, have unique properties with potential value for nanotechnology. The availability and ability to selectively functionalize this special class of nanodiamond materials opens new possibilities for surface-modification, for high-efficiency field emitters in molecular electronics, as seed crystals for diamond growth, or as robust mechanical coatings. The properties of self-assembled monolayers (SAMs) of diamondoids are thus of fundamental interest for a variety of emerging applications. This paper presents the effects of thiol substitution position and polymantane order on diamondoid SAMs on gold using near-edge X-ray absorption fine structure spectroscopy (NEXAFS) and X-ray photoelectron spectroscopy (XPS). A framework to determine both molecular tilt and twist through NEXAFS is presented and reveals highly ordered diamondoid SAMs, with the molecular orientation controlled by the thiol location. C 1s and S 2p binding energies are lower in adamantane thiol than alkane thiols on gold by 0.67 {+-} 0.05 eV and 0.16 {+-} 0.04 eV respectively. These binding energies vary with diamondoid monolayer structure and thiol substitution position, consistent with different amounts of steric strain and electronic interaction with the substrate. This work demonstrates control over the assembly, in particular the orientational and electronic structure, providing a flexible design of surface properties with this exciting new class of diamond clusters.

  5. Vibronic fine structure in high-resolution x-ray absorption spectra from ion-bombarded boron nitride nanotubes

    SciTech Connect (OSTI)

    Petravic, Mladen; Peter, Robert; Varasanec, Marijana; Li Luhua; Chen Ying; Cowie, Bruce C. C.

    2013-05-15

    The authors have applied high-resolution near-edge x-ray absorption fine structure measurements around the nitrogen K-edge to study the effects of ion-bombardment on near-surface properties of boron nitride nanotubes. A notable difference has been observed between surface sensitive partial electron yield (PEY) and bulk sensitive total electron yield (TEY) fine-structure measurements. The authors assign the PEY fine structure to the coupling of excited molecular vibrational modes to electronic transitions in NO molecules trapped just below the surface. Oxidation resistance of the boron nitride nanotubes is significantly reduced by low energy ion bombardment, as broken B-N bonds are replaced by N-O bonds involving oxygen present in the surface region. In contrast to the PEY spectra, the bulk sensitive TEY measurements on as-grown samples do not exhibit any fine structure while the ion-bombarded samples show a clear vibronic signature of molecular nitrogen.

  6. X-ray absorption fine structure spectroscopic study of uranium nitrides

    SciTech Connect (OSTI)

    Poineau, Frederic [University of Nevada, Las Vegas; Yeamans, Charles B. [University of California, Berkeley; Cerefice, Gary S. [University of Nevada, Las Vegas; Sattelberger, Alfred P [Argonne National Laboratory (ANL); Czerwinski, Ken R. [University of Nevada, Las Vegas

    2012-01-01

    Uranium mononitride (UN), sesquinitride (U2N3) and dinitride (UN2) were characterized by extended X-Ray absorption fine structure spectroscopy. Analysis on UN indicate the presence of three uranium shells at distances of 3.46(3), 4.89(5) and 6.01(6) A and a nitrogen shell at a distance of 2.46(2) A . For U2N3, two absorbing uranium atoms at different crystallographic positions are present in the structure. One of the uranium atoms is surrounded by nitrogen atoms at 2.28(2) A and by uranium atoms at 3.66(4) and 3.95(4) A . The second type of uranium atom is surrounded by nitrogen atoms at 2.33(2) and 2.64(3) A and by uranium atoms at 3.66(4), 3.95(4) and 5.31(5) A . Results on UN2 indicate two uranium shells at 3.71(4) and 5.32(5) A and two nitrogen shells at 2.28(2).

  7. Determining Orientational Structure of Diamondoid Thiols Attached to Silver Using Near Edge X-ray Absorption Fine Structure Spectroscopy

    SciTech Connect (OSTI)

    Willey, T M; Lee, J I; Fabbri, J D; Wang, D; Nielsen, M; Randel, J C; Schreiner, P R; Fokin, A A; Tkachenko, B A; Fokina, N A; Dahl, J P; Carlson, R K; Terminello, L J; Melosh, N A; van Buuren, T

    2008-10-07

    Near-edge x-ray absorption fine structure spectroscopy (NEXAFS) is a powerful tool for determination of molecular orientation in self-assembled monolayers and other surface-attached molecules. A general framework for using NEXAFS to simultaneously determine molecular tilt and twist of rigid molecules attached to surfaces is presented. This framework is applied to self-assembled monolayers of higher diamondoid, hydrocarbon molecules with cubic-diamond-cage structures. Diamondoid monolayers chemisorbed on metal substrates are known to exhibit interesting electronic and surface properties. This work compares molecular orientation in monolayers prepared on silver substrates using two different thiol positional isomers of [121]tetramantane, and thiols derived from two different pentamantane structural isomers, [1212]pentamantane and [1(2,3)4]pentamantane. The observed differences in monolayer structure demonstrate the utility and limitations of NEXAFS spectroscopy and the framework. The results also demonstrate the ability to control diamondoid assembly, in particular the molecular orientational structure, providing a flexible platform for the modification of surface properties with this exciting new class of nanodiamond materials.

  8. X-ray absorption fine structure (XAFS) analyses of Ni species trapped in graphene sheet of carbon nanofibers

    SciTech Connect (OSTI)

    Ushiro, Mayuko; Uno, Kanae; Fujikawa, Takashi; Sato, Yoshinori; Tohji, Kazuyuki; Watari, Fumio; Chun, W.-J.; Koike, Yuichiro; Asakura, Kiyotaka

    2006-04-01

    Metal impurities in the carbon nanotubes and carbon nanofibers play an important role in understanding their physical and chemical properties. We apply the Ni K-edge x-ray absorption fine structure analyses to the local electronic and geometric structures around embedded Ni impurities used as catalysts in a carbon nanofiber in combination with multiple scattering analyses. We find almost Ni catalysts as metal particles are removed by the purification treatment. Even after the purification, residual 100 ppm Ni species are still absorbed; most of them are in monomer structure with Ni-C bond length 1.83 A, and each of them is substituted for a carbon atom in a graphene sheet.

  9. X-ray absorption fine structure spectroscopic determination of plutonium speciation at the Rocky Flats environmental technology

    SciTech Connect (OSTI)

    Lezama-pacheco, Juan S; Conradson, Steven D; Clark, David L

    2008-01-01

    X-ray Absorption Fine Structure spectroscopy was used to probe the speciation of the ppm level Pu in thirteen soil and concrete samples from the Rocky Flats Environmental Technology Site in support of the site remediation effort that has been successfully completed since these measurements. In addition to X-ray Absorption Near Edge Spectra, two of the samples yielded Extended X-ray Absorption Fine Structure spectra that could be analyzed by curve-fits. Most of these spectra exhibited features consistent with PU(IV), and more specificaJly, PuO{sub 2+x}-type speciation. Two were ambiguous, possibly indicating that Pu that was originally present in a different form was transforming into PuO{sub 2+x}, and one was interpreted as demonstrating the presence of an unusual Pu(VI) compound, consistent with its source being spills from a PUREX purification line onto a concrete floor and the resultant extreme conditions. These experimental results therefore validated models that predicted that insoluble PuO{sub 2+x} would be the most stable form of Pu in equilibrium with air and water even when the source terms were most likely Pu metal with organic compounds or a Pu fire. A corollary of these models' predictions and other in situ observations is therefore that the minimal transport of Pu that occurred on the site was via the resuspension and mobilization of colloidal particles. Under these conditions, the small amounts of diffusely distributed Pu that were left on the site after its remediation pose only a negligible hazard.

  10. Near-edge X-ray absorption fine-structure spectroscopy of naphthalene diimide-thiophene co-polymers

    SciTech Connect (OSTI)

    Gann, Eliot; McNeill, Christopher R., E-mail: christopher.mcneill@monash.edu [Department of Materials Engineering, Monash University, Wellington Road, Clayton, Victoria 3800 (Australia); Szumilo, Monika; Sirringhaus, Henning [Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom)] [Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Sommer, Michael [Institute of Macromolecular Chemistry, University of Freiburg, Stefan-Meier-Str. 31, 79104 Freiburg (Germany)] [Institute of Macromolecular Chemistry, University of Freiburg, Stefan-Meier-Str. 31, 79104 Freiburg (Germany); Maniam, Subashani; Langford, Steven J. [School of Chemistry, Monash University, Wellington Road, Clayton, Victoria 3800 (Australia)] [School of Chemistry, Monash University, Wellington Road, Clayton, Victoria 3800 (Australia); Thomsen, Lars [Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168 (Australia)] [Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168 (Australia)

    2014-04-28

    Near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy is an important tool for probing the structure of conjugated polymer films used in organic electronic devices. High-performance conjugated polymers are often donor-acceptor co-polymers which feature a repeat unit with multiple functional groups. To facilitate better application of NEXAFS spectroscopy to the study of such materials, improved understanding of the observed NEXAFS spectral features is required. In order to examine how the NEXAFS spectrum of a donor-acceptor co-polymer relates to the properties of the sub-units, a series of naphthalene diimide-thiophene-based co-polymers have been studied where the nature and length of the donor co-monomer has been systematically varied. The spectra of these materials are compared with that of a thiophene homopolymer and naphthalene diimide monomer enabling peak assignment and the influence of inter-unit electronic coupling to be assessed. We find that while it is possible to attribute peaks within the ?* manifold as arising primarily due to the naphthalene diimide or thiophene sub-units, very similar dichroism of these peaks is observed indicating that it may not be possible to separately probe the molecular orientation of the separate sub-units with carbon K-edge NEXAFS spectroscopy.

  11. Studies of vibrational properties in Ga stabilized delta-Pu by extended X-ray absorption fine structure

    SciTech Connect (OSTI)

    Allen, P.G.; Henderson, A.L.; Sylwester, E.R.; Turchi, P.E.A.; Shen, T.H.; Gallegos, G.F.; Booth, C.H.

    2002-02-14

    Temperature dependent extended x-ray absorption fine structure (EXAFS) spectra were measured for a 3.3 at. % Ga stabilized Pu alloy over the range T= 20 - 300 K. EXAFS data were acquired at both the Ga K-edge and the Pu L{sub III} edge. Curve-fits were performed to the first shell interactions to obtain pair-distance distribution widths, {sigma}, as a function of temperature. The temperature dependence of {sigma}(T) was accurately modeled using a correlated-Debye model for the lattice vibrational properties, suggesting Debye-like behavior in this material. Using this formalism, we obtain pair-specific correlated-Debye temperatures, {Theta}{sub cD}, of 110.7 {+-} 1.7 K and 202.6 {+-} 3.7 K, for the Pu-Pu and Ga-Pu pairs, respectively. The result for the Pu-{Theta}{sub cD} value compares well with previous vibrational studies on {delta}-Pu. In addition, our results represent the first unambiguous determination of Ga-specific vibrational properties in Pu-Ga alloys, i.e, {Theta}{sub cD} for the Ga-Pu pair. Because the Debye temperature can be related to a measure of the lattice stiffness, these results indicate the Ga-Pu bonds are significantly stronger than the Pu-Pu bonds. This effect has important implications for lattice stabilization mechanisms in these alloys.

  12. An X-ray Absorption Fine Structure study of Au adsorbed onto the non-metabolizing cells of two soil bacterial species

    SciTech Connect (OSTI)

    Song, Zhen; Kenney, Janice P.L.; Fein, Jeremy B.; Bunker, Bruce A.

    2015-02-09

    Gram-positive and Gram-negative bacterial cells can remove Au from Au(III)-chloride solutions, and the extent of removal is strongly pH dependent. In order to determine the removal mechanisms, X-ray Absorption Fine Structure (XAFS) spectroscopy experiments were conducted on non-metabolizing biomass of Bacillus subtilis and Pseudomonas putida with fixed Au(III) concentrations over a range of bacterial concentrations and pH values. X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) data on both bacterial species indicate that more than 90% of the Au atoms on the bacterial cell walls were reduced to Au(I). In contrast to what has been observed for Au(III) interaction with metabolizing bacterial cells, no Au(0) or Au-Au nearest neighbors were observed in our experimental systems. All of the removed Au was present as adsorbed bacterial surface complexes. For both species, the XAFS data suggest that although Au-chloride-hydroxide aqueous complexes dominate the speciation of Au in solution, Au on the bacterial cell wall is characterized predominantly by binding of Au atoms to sulfhydryl functional groups and amine and/or carboxyl functional groups, and the relative importance of the sulfhydryl groups increases with increasing pH and with decreasing Au loading. The XAFS data for both microorganism species suggest that adsorption is the first step in the formation of Au nanoparticles by bacteria, and the results enhance our ability to account for the behavior of Au in bacteria-bearing geologic systems.

  13. Versatile plug flow catalytic cell for in situ transmission/fluorescence x-ray absorption fine structure measurements

    SciTech Connect (OSTI)

    Centomo, P.; Zecca, M. [Dipartimento di Scienze Chimiche, via Marzolo 1, Universita degli Studi di Padova, 35131 Padova (Italy); Meneghini, C. [Dipartimento di Scienze, via della Vasca Navale 84, Universita di Roma TRE, 00146 Roma (Italy)

    2013-05-15

    A novel flow-through catalytic cell has been developed for in situ x-ray absorption spectroscopy (XAS) experiments on heterogeneous catalysts under working conditions and in the presence of a liquid and a gas phase. The apparatus allows to carry out XAS measurements in both the transmission and fluorescence modes, at moderate temperature (from RT to 50-80 Degree-Sign C) and low-medium gas pressure (up to 7-8 bars). The materials employed are compatible with several chemicals such as those involved in the direct synthesis of hydrogen peroxide (O{sub 2}, H{sub 2}, H{sub 2}O{sub 2}, methanol). The versatile design of the cell allows to fit it to different experimental setups in synchrotron radiation beamlines. It was used successfully for the first time to test nanostructured Pd catalysts during the direct synthesis of hydrogen peroxide (H{sub 2}O{sub 2}) in methanol solution from dihydrogen and dioxygen.

  14. PRELIMINARY IN-SITU X-RAY ABSORPTION FINE STRUCTURE EXAMINATION OF PT/C AND PTCO/C CATHODE CATALYSTS IN AN OPERATIONAL POLYMER ELECTROLYTE FUEL CELL

    SciTech Connect (OSTI)

    Phelan, B.T.; Myers, D.J.; Smith, M.C.

    2009-01-01

    State-of-the-art polymer electrolyte fuel cells require a conditioning period to reach optimized cell performance. There is insuffi cient understanding about the behavior of catalysts during this period, especially with regard to the changing environment of the cathode electrocatalyst, which is typically Pt nanoparticles supported on high surface area Vulcan XC-72 carbon (Pt/C). The purpose of this research was to record preliminary observations of the changing environment during the conditioning phase using X-Ray Absorption Fine Structure (XAFS) spectroscopy. XAFS was recorded for a Pt/C cathode at the Pt L3-edge and a PtCo/C cathode at both the Pt L3-edge and Co K-edge. Using precision machined graphite cell-blocks, both transmission and fl uorescence data were recorded at Sector 12-BM-B of Argonne National Laboratory’s Advanced Photon Source. The fl uorescence and transmission edge steps allow for a working description of the changing electrocatalyst environment, especially water concentration, at the anode and cathode as functions of operating parameters. These features are discussed in the context of how future analysis may correlate with potential, current and changing apparent thickness of the membrane electrode assembly through loss of catalyst materials (anode, cathode, carbon support). Such direct knowledge of the effect of the conditioning protocol on the electrocatalyst may lead to better catalyst design. In turn, this may lead to minimizing, or even eliminating, the conditioning period.

  15. Effect of Residence Time on Ni-Sorption Mechanisms on Clay and Oxide Minerals: An X-ray Absorption Fine Structure (XAFS) Study

    E-Print Network [OSTI]

    Sparks, Donald L.

    Effect of Residence Time on Ni-Sorption Mechanisms on Clay and Oxide Minerals: An X-ray Absorption minerals is typically fast initially, then the rates gradually diminish. In the literature the decline

  16. Structural characterization of Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3} as a function of temperature using neutron powder diffraction and extended X-ray absorption fine structure techniques

    SciTech Connect (OSTI)

    Mansour, A. N.; Wong-Ng, W.; Huang, Q.; Tang, W.; Thompson, A.; Sharp, J.

    2014-08-28

    The structure of Bi{sub 2}Te{sub 3} (Seebeck coefficient Standard Reference Material (SRM™ 3451)) and the related phase Sb{sub 2}Te{sub 3} have been characterized as a function of temperature using the neutron powder diffraction (NPD) and the extended X-ray absorption fine structure (EXAFS) techniques. The neutron structural studies were carried out from 20?K to 300?K for Bi{sub 2}Te{sub 3} and from 10?K to 298?K for Sb{sub 2}Te{sub 3}. The EXAFS technique for studying the local structure of the two compounds was conducted from 19?K to 298?K. Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3} are isostructural, with a space group of R3{sup ¯}m. The structure consists of repeated quintuple layers of atoms, Te2-M-Te1-M-Te2 (where M?=?Bi or Sb) stacking along the c-axis of the unit cell. EXAFS was used to examine the bond distances and static and thermal disorders for the first three shells of Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3} as a function of temperature. The temperature dependencies of thermal disorders were analyzed using the Debye and Einstein models for lattice vibrations. The Debye and Einstein temperatures for the first two shells of Bi{sub 2}Te{sub 3} are similar to those of Sb{sub 2}Te{sub 3} within the uncertainty in the data. However, the Debye and Einstein temperatures for the third shell of Bi-Bi are significantly lower than those of the third shell of Sb-Sb. The Einstein temperature for the third shell is consistent with a soft phonon mode in both Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3}. The lower Einstein temperature of Bi-Bi relative to Sb-Sb is consistent with the lower value of thermal conductivity of Bi{sub 2}Te{sub 3} relative to Sb{sub 2}Te{sub 3}.

  17. Investigating the fine grained structure of networks

    E-Print Network [OSTI]

    Macindoe, Owen

    2010-01-01

    In this thesis I explore a novel representation for characterizing a graph's fine grained structure. The key idea is that this structure can be represented as a distribution of the structural features of subgraphs. I ...

  18. Interrogation of Surface, Skin, and Core Orientation in Thermotropic Liquid-Crystalline Copolyester Moldings by Near-Edge X-ray Absorption Fine Structure and Wide-Angle X-ray Scattering

    SciTech Connect (OSTI)

    Rendon,S.; Bubeck, R.; Thomas, L.; Burghardt, W.; Hexemer, A.; Fischer, D.

    2007-01-01

    Injection molding thermotropic liquid-crystalline polymers (TLCPs) usually results in the fabrication of molded articles that possess complex states of orientation that vary greatly as a function of thickness. 'Skin-core' morphologies are often observed in TLCP moldings. Given that both 'core' and 'skin' orientation states may often differ both in magnitude and direction, deconvolution of these complex orientation states requires a method to separately characterize molecular orientation in the surface region. A combination of two-dimensional wide-angle X-ray scattering (WAXS) in transmission and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy is used to probe the molecular orientation in injection molded plaques fabricated from a 4,4'-dihydroxy-{alpha}-methylstilbene (DH{alpha}MS)-based thermotropic liquid crystalline copolyester. Partial electron yield (PEY) mode NEXAFS is a noninvasive ex situ characterization tool with exquisite surface sensitivity that samples to a depth of 2 nm. The effects of plaque geometry and injection molding processing conditions on surface orientation in the regions on- and off- axis to the centerline of injection molded plaques are presented and discussed. Quantitative comparisons are made between orientation parameters obtained by NEXAFS and those from 2D WAXS in transmission, which are dominated by the microstructure in the skin and core regions. Some qualitative comparisons are also made with 2D WAXS results from the literature.

  19. The Meaning Of The Fine Structure Constant

    E-Print Network [OSTI]

    R. L. Oldershaw

    2009-02-21

    A possible explanation is offered for the longstanding mystery surrounding the meaning of the fine structure constant. The reasoning is based on a discrete self-similar cosmological paradigm that has shown promise in explaining the general scaling properties of nature's global hierarchy. The discrete scale invariance of the paradigm implies that "strong gravity" governs gravitational interactions within atomic scale systems. Given the revised gravitational coupling constant and Planck mass, one can demonstrate that the fine structure constant is the ratio of the strengths of the unit electromagnetic interaction and the unit gravitational interaction within atomic scale systems. [Abridged

  20. Gravitational Interactions and Fine-Structure Constant

    E-Print Network [OSTI]

    U. D. Jentschura; J. H. Noble; I. Nandori

    2015-02-01

    Electromagnetic and gravitational central-field problems are studied with relativistic quantum mechanics on curved space-time backgrounds. Corrections to the transition current are identified. Analogies of the gravitational and electromagnetic spectra suggest the definition of a gravitational fine-structure constant. The electromagnetic and gravitational coupling constants enter the Einstein-Hilbert-Maxwell Lagrangian. We postulate that the variational principle holds with regard to a global dilation transformation of the space-time coordinates. The variation suggests is consistent with a functional relationship of the form alpha_QED being proportional to alpha_G^(1/2), where alpha_QED is the electrodynamic fine-structure constant, and alpha_G its gravitational analogue.

  1. CMB constraints on the fine structure constant

    E-Print Network [OSTI]

    Kazuhide Ichikawa; Toru Kanzaki; Masahiro Kawasaki

    2006-05-25

    We study constraints on time variation of the fine structure constant alpha from cosmic microwave background (CMB) taking into account simultaneous change in alpha and the electron mass m_e which might be implied in unification theories. We obtain the constraints -0.097 < Delta alpha/alpha < 0.034 at 95% C.L. using WMAP data only, and -0.042 < Delta alpha/alpha < 0.026 combining with the constraint on the Hubble parameter by the HST Hubble Key Project. These are improved by 15% compared with constraints assuming only alpha varies. We discuss other relations between variations in alpha and m_e but we do not find evidence for varying alpha.

  2. Effects of {pi}-stacking interactions on the near carbon K-edge x-ray absorption fine structure: A theoretical study of the ethylene pentamer and the phthalocyanine dimer

    SciTech Connect (OSTI)

    Linares, Mathieu; Stafstroem, Sven; Norman, Patrick [Department of Physics, Chemistry and Biology, Linkoeping University, SE-581 83 Linkoeping (Sweden)

    2009-03-14

    X-ray absorption spectra have been determined for ethylene and free base phthalocyanine at the carbon K-edge with use of the complex polarization propagator method combined with Kohn-Sham density functional theory and the Coulomb attenuated method B3LYP exchange-correlation functional. Apart from isolated molecules, the study includes {pi}-stacked systems of the phthalocyanine dimer and the ethylene dimer, trimer, tetramer, and pentamer. For ethylene, {pi}-stacking involves a reduction in transition energy of the valence {pi}*-band by some 70 meV and large spectral changes (regarding also shape and intensity) of the Rydberg bands. For phthalocyanine, there are large spectral changes in the entire valence {pi}*-part of the spectrum.

  3. Fine Structure of Dark Energy and New Physics

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jejjala, Vishnu; Kavic, Michael; Minic, Djordje

    2007-01-01

    Following our recent work on the cosmological constant problem, in this letter we make a specific proposal regarding the fine structure (i.e., the spectrum) of dark energy. The proposal is motivated by a deep analogy between the blackbody radiation problem, which led to the development of quantum theory, and the cosmological constant problem, for which we have recently argued calls for a conceptual extension of the quantum theory. We argue that the fine structure of dark energy is governed by a Wien distribution, indicating its dual quantum and classical nature. We discuss observational consequences of such a picture of darkmore »energy and constrain the distribution function.« less

  4. Electronic structure of titania aerogels: Soft x-ray absorption...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Electronic structure of titania aerogels: Soft x-ray absorption study Citation Details In-Document Search Title: Electronic structure of titania aerogels: Soft...

  5. The Effective Fine Structure Constant at TESLA Energies

    E-Print Network [OSTI]

    F. Jegerlehner

    2001-05-27

    We present a new estimate of the hadronic contribution to the shift in the fine structure constant at LEP and TESLA energies and calculate the effective fine structure constant. Substantial progress in a precise determination of this important parameter is a consequence of substantially improved total cross section measurements by the BES II collaboration and an improved theoretical understanding. In the standard approach which relies to a large extend on experimental data we find $\\Delta \\al_{\\rm hadrons}^{(5)}(\\mz) = 0.027896 \\pm 0.000395$ which yields $\\alpha^{-1}(\\mz) = 128.907 \\pm 0.054$. Another approach, using the Adler function as a tool to compare theory and experiment, allows us to to extend the applicability of perturbative QCD in a controlled manner. The result in this case reads $\\Delta\\alpha^{(5)}_{\\rm had}(M_Z^2) = 0.027730 \\pm 0.000209$ and hence $\\alpha^{-1}(\\mz) = 128.930 \\pm 0.029$. At TESLA energies a new problem shows up with the definition of an effective charge. A possible solution of the problem is presented. Prospects for further progress in a precise determination of the effective fine structure constant are discussed.

  6. Physics 250 -Measurements of the Fine Structure Constant Derek Kimball January 2000 1

    E-Print Network [OSTI]

    Budker, Dmitry

    Physics 250 - Measurements of the Fine Structure Constant Derek Kimball January 2000 1 #12;Physics 250 - Measurements of the Fine Structure Constant Derek Kimball January 2000 2 #12;Physics 250 - Measurements of the Fine Structure Constant Derek Kimball January 2000 3 #12;Physics 250 - Measurements

  7. The fine structure line deficit in S 140

    E-Print Network [OSTI]

    Ossenkopf, Volker; Okada, Yoko; Mookerjea, Bhaswati; van der Tak, Floris F S; Simon, Robert; Pütz, Patrick; Güsten, Rolf

    2015-01-01

    We try to understand the gas heating and cooling in the S 140 star forming region by spatially and spectrally resolving the distribution of the main cooling lines with GREAT/SOFIA. We mapped the fine structure lines of [OI] (63 {\\mu}m) and [CII] (158 {\\mu}m) and the rotational transitions of CO 13-12 and 16-15 with GREAT/SOFIA and analyzed the spatial and velocity structure to assign the emission to individual heating sources. We measure the optical depth of the [CII] line and perform radiative transfer computations for all observed transitions. By comparing the line intensities with the far-infrared continuum we can assess the total cooling budget and measure the gas heating efficiency. The main emission of fine structure lines in S 140 stems from a 8.3'' region close to the infrared source IRS 2 that is not prominent at any other wavelength. It can be explained by a photon-dominated region (PDR) structure around the embedded cluster if we assume that the [OI] line intensity is reduced by a factor seven due ...

  8. Herschel Galactic plane survey of [NII] fine structure emission

    E-Print Network [OSTI]

    Goldsmith, Paul F; Langer, William D; Pineda, Jorge L

    2015-01-01

    We present the first large scale high angular resolution survey of ionized nitrogen in the Galactic Plane through emission of its two fine structure transitions ([NII]) at 122 $\\mu$m and 205 $\\mu$m. The observations were largely obtained with the PACS instrument onboard the Herschel Space Observatory. The lines-of-sight were in the Galactic plane, following those of the Herschel OTKP project GOT C+. Both lines are reliably detected at the 10$^{-8}$ - 10$^{-7}$ $W$m$^{-2}$sr$^{-1}$ level over the range -60$^{o}$ $\\leq$ $l$ $\\leq$ 60$^{o}$. The $rms$ of the intensity among the 25 PACS spaxels of a given pointing is typically less than one third of the mean intensity, showing that the emission is extended. [NII] is produced in gas in which hydrogen is ionized, and collisional excitation is by electrons. The ratio of the two fine structure transitions provides a direct measurement of the electron density, yielding $n(e)$ largely in the range 10 to 50 cm$^{-3}$ with an average value of 29 cm$^{-3}$ and N$^+$ colum...

  9. Hydrogen Atom and Time Variation of Fine-Structure Constant

    E-Print Network [OSTI]

    Mu-Lin Yan

    2009-11-21

    In this paper, we have solved the de Sitter special relativistic ($\\mathcal{SR}_{cR}$-) Dirac equation of hydrogen in the earth-QSO(quasar) framework reference by means of the adiabatic approach. The aspects of geometry effects of de Sitter space-time described by Beltrami metric are explored and taken into account. It is found that the $\\mathcal{SR}_{cR}$-Dirac equation of hydrogen is a time dependent quantum Hamiltonian system. We provide an explicit calculation to justify the adiabatic approach in dealing with this time-dependent system. Since the radius of de Sitter sphere $R$ is cosmologically large, the evolution of the system is very slow so that the adiabatic approximation legitimately works with high accuracy. We conclude that the electromagnetic fine-structure constant, the electron mass and the Planck constant are time variations. This prediction of fine-structure constant is consistent with the presently available observation data. For confirming it further, experiments/observations are required.

  10. Varying fine structure 'constant' and charged black holes

    SciTech Connect (OSTI)

    Bekenstein, Jacob D.; Schiffer, Marcelo

    2009-12-15

    Speculation that the fine-structure constant {alpha} varies in spacetime has a long history. We derive, in 4-D general relativity and in isotropic coordinates, the solution for a charged spherical black hole according to the framework for dynamical {alpha} J. D. Bekenstein, Phys. Rev. D 25, 1527 (1982).. This solution coincides with a previously known one-parameter extension of the dilatonic black hole family. Among the notable properties of varying-{alpha} charged black holes are adherence to a 'no hair' principle, the absence of the inner (Cauchy) horizon of the Reissner-Nordstroem black holes, the nonexistence of precisely extremal black holes, and the appearance of naked singularities in an analytic extension of the relevant metric. The exteriors of almost extremal electrically (magnetically) charged black holes have simple structures which makes their influence on applied magnetic (electric) fields transparent. We rederive the thermodynamic functions of the modified black holes; the otherwise difficult calculation of the electric potential is done by a shortcut. We confirm that variability of {alpha} in the wake of expansion of the universe does not threaten the generalized second law.

  11. Quasi-static energy absorption of hollow microlattice structures

    SciTech Connect (OSTI)

    Liu, YL; Schaedler, TA; Jacobsen, AJ; Chen, X

    2014-12-01

    We present a comprehensive modeling and numerical study focusing on the energy quasi-static crushing behavior and energy absorption characteristics of hollow tube microlattice structures. The peak stress and effective plateau stress of the hollow microlattice structures are deduced for different geometrical parameters which gives volume and mass densities of energy absorption, D-v and D-m, scale with the relative density, (rho) over bar, as D-v similar to (rho) over bar (1) (5) and D-m similar to (rho) over bar (0 5), respectively, fitting very well to the experimental results of both 60 degrees inclined and 90 degrees predominately microlattices. Then the strategies for energy absorption enhancement are proposed for the engineering design of microlattice structures. By introducing a gradient in the thickness or radius of the lattice members, the buckle propagation can be modulated resulting in an increase in energy absorption density that can exceed 40%. Liquid filler is another approach to improve energy absorption by strengthening the microtruss via circumference expansion, and the gain may be over 100% in terms of volume density. Insight into the correlations between microlattice architecture and energy absorption performance combined with the high degree of architecture control paves the way for designing high performance microlattice structures for a range of impact and impulse mitigation applications for vehicles and structures. (C) 2014 Elsevier Ltd. All rights reserved.

  12. Ocean acoustic wave propagation and ray method correspondence: Internal wave fine structure

    E-Print Network [OSTI]

    Tomsovic, Steve

    Ocean acoustic wave propagation and ray method correspondence: Internal wave fine structure 2004 Acoustic wave fields propagating long ranges through the ocean are refracted As acoustic waves propagate long ranges through the deep ocean, they are refracted by inhomogeneities

  13. Background proportional enhancement of the extended fine structure in nonresonant inelastic x-ray scattering

    E-Print Network [OSTI]

    Seidler, Gerald T.

    Background proportional enhancement of the extended fine structure in nonresonant inelastic x is proportional to the strong q-dependent evolution in shape and magnitude of the atomic background. This en

  14. Impact of instrumental systematic errors on fine-structure constant measurements with quasar spectra

    E-Print Network [OSTI]

    J. B. Whitmore; M. T. Murphy

    2014-11-18

    We present a new `supercalibration' technique for measuring systematic distortions in the wavelength scales of high resolution spectrographs. By comparing spectra of `solar twin' stars or asteroids with a reference laboratory solar spectrum, distortions in the standard thorium--argon calibration can be tracked with $\\sim$10 m s$^{-1}$ precision over the entire optical wavelength range on scales of both echelle orders ($\\sim$50--100 \\AA) and entire spectrographs arms ($\\sim$1000--3000 \\AA). Using archival spectra from the past 20 years we have probed the supercalibration history of the VLT--UVES and Keck--HIRES spectrographs. We find that systematic errors in their wavelength scales are ubiquitous and substantial, with long-range distortions varying between typically $\\pm$200 m s$^{-1}$ per 1000 \\AA. We apply a simple model of these distortions to simulated spectra that characterize the large UVES and HIRES quasar samples which previously indicated possible evidence for cosmological variations in the fine-structure constant, $\\alpha$. The spurious deviations in $\\alpha$ produced by the model closely match important aspects of the VLT--UVES quasar results at all redshifts and partially explain the HIRES results, though not self-consistently at all redshifts. That is, the apparent ubiquity, size and general characteristics of the distortions are capable of significantly weakening the evidence for variations in $\\alpha$ from quasar absorption lines.

  15. Exciton fine-structure splitting of telecom wavelength single quantum dots: statistics and external strain tuning

    E-Print Network [OSTI]

    Luca Sapienza; Ralph N. E. Malein; Christopher E. Kuklewicz; Peter E. Kremer; Kartik Srinivasan; Andrew Griffiths; Edmund Clarke; Ming Gong; Richard J. Warburton; Brian D. Gerardot

    2013-09-18

    In a charge tunable device, we investigate the fine structure splitting of neutral excitons in single long-wavelength (1.1\\mu m eV are measured and manipulated. We observe varied response of the splitting to the external strain, including positive and negative tuning slopes, different tuning ranges, and linear and parabolic dependencies, indicating that these physical parameters depend strongly on the unique microscopic structure of the individual quantum dot. To better understand the experimental results, we apply a phenomenological model describing the exciton polarization and fine-structure splitting under uniaxial strain. The model predicts that, with an increased experimental strain tuning range, the fine-structure can be effectively canceled for select telecom wavelength dots using uniaxial strain. These results are promising for the generation of on-demand entangled photon pairs at telecom wavelengths.

  16. Fine structure, hyperfine structure, and Stark effect in the NO A 2~+ state by optical radiofrequency double resonance

    E-Print Network [OSTI]

    Zare, Richard N.

    Fine structure, hyperfine structure, and Stark effect in the NO A 2~+ state by optical radio·frequency double resonance T. Bergeman Columbia Radiation Laboratory, Columbia University, New York, New York 10027 and Department of Physics*, Fordham University, Bronx, New York 10458 R. N. Zare Columbia Radiation Laboratory

  17. MORPHOLOGY, HISTOLOGY, AND FINE STRUCTURE Sensilla on the Antennal Flagellum of Sirex noctilio

    E-Print Network [OSTI]

    MORPHOLOGY, HISTOLOGY, AND FINE STRUCTURE Sensilla on the Antennal Flagellum of Sirex noctilio subterminal pore is seen to be associated with each sensillum. Males had signiÞcantly more uniporous sensory (Pinus taeda L.). S. noctilio has therefore been assessed as being a high risk to native pine forests

  18. THE FINE STRUCTURE OF THE WAX GLAND OF THE HONEY BEE (APIS MELLIFERA L.)

    E-Print Network [OSTI]

    Boyer, Edmond

    THE FINE STRUCTURE OF THE WAX GLAND OF THE HONEY BEE (APIS MELLIFERA L.) Malcolin T. SANFORD Alfred An electron microscopic study was initiated to elucidate the ultrastructure of the wax gland in an actively wax secreting worker honey bee. The investigation showed that the cuticle is penetrated by bundles

  19. MINERAL FINE STRUCTURE OF THE AMERICAN LOBSTER CUTICLE JOSEPH G. KUNKEL,1

    E-Print Network [OSTI]

    Kunkel, Joseph G.

    MINERAL FINE STRUCTURE OF THE AMERICAN LOBSTER CUTICLE JOSEPH G. KUNKEL,1 * WOLFRAM NAGEL2 minerals. We propose that calcite is invested in neutralizing an acidifying environment modulated to the epicuticle covering this mineralized surface unleashes an immediate efflux of carbonate, accentuating

  20. THERMAL FINE STRUCTURE AND MAGNETIC FIELDS IN THE SOLAR ATMOSPHERE: SPICULES AND FIBRILS

    SciTech Connect (OSTI)

    Judge, Philip G.; Low, Boon Chye [High Altitude Observatory, National Center for Atmospheric Research , P.O. Box 3000, Boulder, CO 80307-3000 (United States); Tritschler, Alexandra, E-mail: judge@ucar.edu, E-mail: low@ucar.edu, E-mail: ali@nso.edu [National Solar Observatory/Sacramento Peak , P.O. Box 62, Sunspot, NM-88349 (United States)

    2011-03-20

    The relationship between observed structures in the solar atmosphere and the magnetic fields threading them is known only for the solar photosphere, even then imprecisely. We suggest that some of the fine structures in the more tenuous chromosphere and corona-specifically some populations of spicules and fibrils-correspond to warps in two-dimensional sheet-like structures, as an alternative to conventional interpretations in terms of tube-like structures. The sheets are perhaps related to magnetic tangential discontinuities, which Parker has argued arise naturally in low-{beta} conditions. Some consequences of this suggestion, if it can be confirmed, are discussed.

  1. Local structure and polarization resistance of Ce doped SrMnO{sub 3} using extended x-ray fine structure analysis

    SciTech Connect (OSTI)

    Ryu, Jiseung; Lee, Heesoo, E-mail: heesoo@pusan.ac.kr [School of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of)

    2014-09-15

    Changes to the local structure of Sr and Mn atoms in Sr{sub 1?x}Ce{sub x}MnO{sub 3} (SCM) according to increasing Ce content and the effect of the structural change on the polarization resistance of SCM were investigated. The reduction of manganese was confirmed by the absorption edge shift of the Mn K-edge toward lower energies. The noise of oscillation in extended X-ray absorption fine structure k{sup 3}? data at Mn K-edge reveals the distortion of the local structure of Mn atoms, and the peak that indicates the bonding length of Mn-O, Sr/Ce, and -Mn decreased with the addition of Ce content in Fourier transformations of the Mn K-edge. The distortion of the local structure at Mn atoms was affected by the reduced manganese ions having larger ionic radii than Mn{sup 4+}. Meanwhile, few distortions of local atomic structures of Sr atoms occurred, and the average nearest neighboring distances of Sr-O and Sr-Mn are ?2.13?Å and ?2.95?Å, respectively. The average bonding lengths of the Ce-O and Ce-Mn increased because the ionic radius of substituted Ce ion with 12 coordination number is smaller than that of Sr ion, which leads the reduction of Mn ions and the distortion of local structure at the substituted A-site. Therefore, we reasoned that the distortion of the local atomic structure at Mn atoms in MnO{sub 6} and Ce atoms in A-site is one of the causes for interrupting oxygen ion transfers as a geometric factor, which results in an increase in the polarization resistance of SCM within the Ce composition range from 10?mol.?% to 30?mol.?%.

  2. The Analysis of Penumbral Fine Structure Using an Advanced Inversion Technique

    E-Print Network [OSTI]

    Jan Jur?ák; Luis Bellot Rubio; Kiyoshi Ichimoto; Yukio Katsukawa; Bruce Lites; Shin'ichi Nagata; Toshifumi Shimizu; Yoshinori Suematsu; Theodore Tarbell; Alan Title; Saku Tsuneta

    2007-07-11

    We present a method to study the penumbral fine structure using data obtained by the spectropolarimeter onboard HINODE. For the first time, the penumbral filaments can be considered as resolved in spectropolarimetric measurements. This enables us to use inversion codes with only one-component model atmospheres, and thus assign the obtained stratifications of plasma parameters directly to the penumbral fine structure. This approach is applied to the limb-side part of the penumbra in active region NOAA 10923. The preliminary results show a clear dependence of the plasma parameters on continuum intensity in the inner penumbra, i.e. weaker and horizontal magnetic field along with increased line-of-sight velocity are found in the low layers of the bright filaments. The results in the mid penumbra are ambiguous and future analyses are necessary to unveil the magnetic field structure and other plasma parameters there.

  3. FINE-SCALE STRUCTURES OF FLUX ROPES TRACKED BY ERUPTING MATERIAL

    SciTech Connect (OSTI)

    Li Ting; Zhang Jun E-mail: zjun@nao.cas.cn

    2013-06-20

    We present Solar Dynamics Observatory observations of two flux ropes tracked out by material from a surge and a failed filament eruption on 2012 July 29 and August 4, respectively. For the first event, the interaction between the erupting surge and a loop-shaped filament in the east seems to 'peel off' the filament and add bright mass into the flux rope body. The second event is associated with a C-class flare that occurs several minutes before the filament activation. The two flux ropes are, respectively, composed of 85 {+-} 12 and 102 {+-} 15 fine-scale structures, with an average width of about 1.''6. Our observations show that two extreme ends of the flux rope are rooted in opposite polarity fields and each end is composed of multiple footpoints (FPs) of fine-scale structures. The FPs of the fine-scale structures are located at network magnetic fields, with magnetic fluxes from 5.6 Multiplication-Sign 10{sup 18} Mx to 8.6 Multiplication-Sign 10{sup 19} Mx. Moreover, almost half of the FPs show converging motion of smaller magnetic structures over 10 hr before the appearance of the flux rope. By calculating the magnetic fields of the FPs, we deduce that the two flux ropes occupy at least 4.3 Multiplication-Sign 10{sup 20} Mx and 7.6 Multiplication-Sign 10{sup 20} Mx magnetic fluxes, respectively.

  4. RAPID COMMUNICATION Near-Edge X-Ray Absorption Fine Structure (NEXAFS) Microscopy of a

    E-Print Network [OSTI]

    of a Polycarbonate/Poly(acrylonitrile/butadiene/styrene) Blend C. C. SLOOP,1 * H. ADE,2 R. E. FORNES,2 R. D. GILBERT; revised 11 December 2000; accepted 20 December 2000 Published online 00 Month 2001 Keywords: polycarbonate/acrylonitrile­butadiene called PC/acrylonitrile­butadiene­styrene (ABS) blends, are complex mixtures. The ABS component consists

  5. In Situ Grazing-Incidence Extended X-ray Absorption Fine Structure Study of

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(Journal Article)lasers(Journal Article)CurvesAnodic Materials inSciTech Connect

  6. He I vector magnetic field maps of a sunspot and its superpenumbral fine-structure

    E-Print Network [OSTI]

    Schad, T A; Lin, H; Tritschler, A

    2015-01-01

    Advanced inversions of high-resolution spectropolarimetric observations of the He I triplet at 1083 nm are used to generate unique maps of the chromospheric magnetic field vector across a sunspot and its superpenumbral canopy. The observations were acquired by the Facility Infrared Spectropolarimeter (FIRS) at the Dunn Solar Telescope (DST) on 29 January 2012. Multiple atmospheric models are employed in the inversions, as superpenumbral Stokes profiles are dominated by atomic-level polarization while sunspot profiles are Zeeman-dominated but also exhibit signatures perhaps induced by symmetry breaking effects of the radiation field incident on the chromospheric material. We derive the equilibrium magnetic structure of a sunspot in the chromosphere, and further show that the superpenumbral magnetic field does not appear finely structured, unlike the observed intensity structure. This suggests fibrils are not concentrations of magnetic flux but rather distinguished by individualized thermalization. We also dire...

  7. Structural Detuning of Pump Absorption Rate in Doped Fiber for the Enhancement of Power Conversion Efficiency

    E-Print Network [OSTI]

    Park, Namkyoo

    Structural Detuning of Pump Absorption Rate in Doped Fiber for the Enhancement of Power Conversion Doped Fiber Amplifier. With proper adjustments on doping profiles for the reduction of pump absorption rate, it becomes possible to optimize pump evolution map inside the doped fiber to get better power

  8. The variation of the fine-structure constant from disformal couplings

    E-Print Network [OSTI]

    van de Bruck, Carsten; Nunes, Nelson J

    2015-01-01

    We study a theory in which the electromagnetic field is disformally coupled to a scalar field, in addition to a usual non-minimal electromagnetic coupling. We show that disformal couplings modify the expression for the fine-structure constant, alpha. As a result, the theory we consider can explain the non-zero reported variation in the evolution of alpha by purely considering disformal couplings. We also find that if matter and photons are coupled in the same way to the scalar field, disformal couplings itself do not lead to a variation of the fine-structure constant. A number of scenarios are discussed consistent with the current astrophysical, geochemical, laboratory and the cosmic microwave background radiation constraints on the cosmological evolution of alpha. The models presented are also consistent with the current type Ia supernovae constraints on the effective dark energy equation of state. We find that the Oklo bound in particular puts strong constraints on the model parameters. From our numerical r...

  9. Fine and hyperfine structure of P-levels in muonic hydrogen

    E-Print Network [OSTI]

    A. P. Martynenko

    2006-10-25

    Corrections of orders $\\alpha^5$ and $\\alpha^6$ are calculated in the fine structure interval $\\Delta E^{fs}=E(2P_{3/2})-E(2P_{1/2})$ and in the hyperfine structure of the energy levels $2P_{1/2}$ and $2P_{3/2}$ in muonic hydrogen. The obtained numerical values $\\Delta E^{fs}= 8352.08 \\mu eV$, $\\Delta \\tilde E^{hfs}(2P_{1/2})=7964.36 \\mu eV$, $\\Delta \\tilde E^{hfs}(2P_{3/2})=3392.59 \\mu eV$ can be considered as a reliable estimate for the comparison with corresponding experimental data and for the extraction of the experimental value of the Lamb shift $(2P-2S)$ in muonic hydrogen.

  10. MHD wave modes resolved in fine-scale chromospheric magnetic structures

    E-Print Network [OSTI]

    Verth, G

    2015-01-01

    Within the last decade, due to significant improvements in the spatial and temporal resolution of chromospheric data, magnetohydrodynamic (MHD) wave studies in this fascinating region of the Sun's atmosphere have risen to the forefront of solar physics research. In this review we begin by reviewing the challenges and debates that have manifested in relation to MHD wave mode identification in fine-scale chromospheric magnetic structures, including spicules, fibrils and mottles. Next we go on to discuss how the process of accurately identifying MHD wave modes also has a crucial role to play in estimating their wave energy flux. This is of cardinal importance for estimating what the possible contribution of MHD waves is to solar atmospheric heating. Finally, we detail how such advances in chromospheric MHD wave studies have also allowed us, for the first time, to implement cutting-edge magnetoseismological techniques that provide new insight into the sub-resolution plasma structuring of the lower solar atmospher...

  11. Improvement of infrared single-photon detectors absorptance by integrated plasmonic structures

    E-Print Network [OSTI]

    Najafi, Faraz

    Plasmonic structures open novel avenues in photodetector development. Optimized illumination configurations are reported to improve p-polarized light absorptance in superconducting-nanowire single-photon detectors (SNSPDs) ...

  12. Band structures Optical absorption Summary Key concepts in Density Functional Theory (II)

    E-Print Network [OSTI]

    Botti, Silvana

    Band structures Optical absorption Summary Key concepts in Density Functional Theory (II) Kohn-Sham scheme, band structure and optical spectra Silvana Botti European Theoretical Spectroscopy Facility (ETSF, Belfast Key concepts in Density Functional Theory (II) Silvana Botti #12;Band structures Optical

  13. Strain-driven growth of GaAs(111) quantum dots with low fine structure splitting

    SciTech Connect (OSTI)

    Yerino, Christopher D.; Jung, Daehwan; Lee, Minjoo Larry; Simmonds, Paul J.; Liang, Baolai; Huffaker, Diana L.; Schneider, Christian; Unsleber, Sebastian; Vo, Minh; Kamp, Martin; Höfling, Sven

    2014-12-22

    Symmetric quantum dots (QDs) on (111)-oriented surfaces are promising candidates for generating polarization-entangled photons due to their low excitonic fine structure splitting (FSS). However, (111) QDs are difficult to grow. The conventional use of compressive strain to drive QD self-assembly fails to form 3D nanostructures on (111) surfaces. Instead, we demonstrate that (111) QDs self-assemble under tensile strain by growing GaAs QDs on an InP(111)A substrate. Tensile GaAs self-assembly produces a low density of QDs with a symmetric triangular morphology. Coherent, tensile QDs are observed without dislocations, and the QDs luminescence at room temperature. Single QD measurements reveal low FSS with a median value of 7.6??eV, due to the high symmetry of the (111) QDs. Tensile self-assembly thus offers a simple route to symmetric (111) QDs for entangled photon emitters.

  14. Engineering quantum dots for electrical control of the fine structure splitting

    E-Print Network [OSTI]

    Pooley, M A; Farrer, I; Ritchie, D A; Shields, A J

    2015-01-01

    We have studied the variation in fine-structure splitting (FSS) under application of vertical electric field in a range of quantum dots grown by different methods. In each sample we confirm that this energy splitting changes linearly over the field range we can access. We conclude that this linear tuning is a general feature of self-assembled quantum dots, observed under different growth conditions, emission wavelengths and in different material systems. Statistical measurements of characteristic parameters such as emission energy, Stark shift and FSS tuning are presented which may provide a guide for future attempts to increase the yield of quantum dots that can be tuned to a minimal value of FSS with vertical electric field.

  15. Engineering quantum dots for electrical control of the fine structure splitting

    E-Print Network [OSTI]

    M. A. Pooley; A. J. Bennett; I. Farrer; D. A. Ritchie; A. J. Shields

    2015-07-22

    We have studied the variation in fine-structure splitting (FSS) under application of vertical electric field in a range of quantum dots grown by different methods. In each sample we confirm that this energy splitting changes linearly over the field range we can access. We conclude that this linear tuning is a general feature of self-assembled quantum dots, observed under different growth conditions, emission wavelengths and in different material systems. Statistical measurements of characteristic parameters such as emission energy, Stark shift and FSS tuning are presented which may provide a guide for future attempts to increase the yield of quantum dots that can be tuned to a minimal value of FSS with vertical electric field.

  16. Fine structure in the large n limit of the non-hermitian Penner matrix model

    E-Print Network [OSTI]

    Gabriel Álvarez; Luis Martínez Alonso; Elena Medina

    2015-07-09

    In this paper we apply results on the asymptotic zero distribution of the Laguerre polynomials to discuss generalizations of the standard large $n$ limit in the non-hermitian Penner matrix model. In these generalizations $g_n n\\to t$, but the product $g_n n$ is not necessarily fixed to the value of the 't Hooft coupling $t$. If $t>1$ and the limit $l = \\lim_{n\\rightarrow \\infty} |\\sin(\\pi/g_n)|^{1/n}$ exists, then the large $n$ limit is well-defined but depends both on $t$ and on $l$. This result implies that for $t>1$ the standard large $n$ limit with $g_n n=t$ fixed is not well-defined. The parameter $l$ determines a fine structure of the asymptotic eigenvalue support: for $l\

  17. The variation of the fine structure constant: testing the dipole model with thermonuclear supernovae

    E-Print Network [OSTI]

    Kraiselburd, Lucila; Negrelli, Carolina; Berro, Enrique García

    2014-01-01

    The large-number hypothesis conjectures that fundamental constants may vary. Accordingly, the spacetime variation of fundamental constants has been an active subject of research for decades. Recently, using data obtained with large telescopes a phenomenological model in which the fine structure constant might vary spatially has been proposed. We test whether this hypothetical spatial variation of {\\alpha}, which follows a dipole law, is compatible with the data of distant thermonuclear supernovae. Unlike previous works, in our calculations we consider not only the variation of the luminosity distance when a varying {\\alpha} is adopted, but we also take into account the variation of the peak luminosity of Type Ia supernovae resulting from a variation of {\\alpha}. This is done using an empirical relation for the peak bolometric magnitude of thermonuclear supernovae that correctly reproduces the results of detailed numerical simulations. We find that there is no significant difference between the several phenome...

  18. Local structure of Fe in Fe-doped misfit-layered calcium cobaltite: An X-ray absorption spectroscopy study

    SciTech Connect (OSTI)

    Prasoetsopha, Natkrita; Pinitsoontorn, Supree; Bootchanont, Atipong; Kidkhunthod, Pinit; Srepusharawoot, Pornjuk; Kamwanna, Teerasak; Amornkitbamrung, Vittaya; Kurosaki, Ken; Yamanaka, Shinsuke

    2013-08-15

    Polycrystalline Ca{sub 3}Co{sub 4?x}Fe{sub x}O{sub 9+?} ceramics (x=0, 0.01, 0.03, 0.05) were fabricated using a simple thermal hydro-decomposition method and a spark plasma sintering technique. Thermoelectric property measurements showed that increasing Fe concentration resulted in a decrease in electrical resistivity, thermopower and thermal conductivity, leading to an improvement in the dimensionless figure-of-merit, >35% for x=0.05 at 1073 K. An X-ray absorption spectroscopy technique was used to investigate the local structure of Fe ions in the Ca{sub 3}Co{sub 4?x}Fe{sub x}O{sub 9+?} structure for the first time. By fitting data from the extended X-ray absorption fine structure (EXAFS) spectra and analyzing the X-ray absorption near-edge structure (XANES) spectra incorporated with first principle simulation, it was shown that Fe was substituted for Co in the the Ca{sub 2}CoO{sub 3} (rocksalt, RS) layer rather than in the CoO{sub 2} layer. Variation in the thermoelectric properties as a function of Fe concentration was attributed to charge transfer between the CoO{sub 2} and the RS layers. The origin of the preferential Fe substitution site was investigated considering the ionic radii of Co and Fe and the total energy of the system. - Graphical abstract: The Fe K-edge XANES spectra of: (a) experimental result in comparison to the simulated spectra when Fe atoms were substituted in the RS layer; (b) with magnetic moment; (c) without magnetic moment, and in the CoO{sub 2} layer; (d) with magnetic moment and (e) without magnetic moment. Highlights: • Synthesis, structural studies, and thermoelectric properties of Ca{sub 3}Co{sub 4?x}Fe{sub x}O{sub 9+?}. • Direct evidence for the local structure of the Fe ions in the Ca{sub 3}Co{sub 4?x}Fe{sub x}O{sub 9+?} using XAS analysis. • EXAFS and XANES analysis showed that Fe was likely to be situated in the RS layer structure. • Changes in TE property with Fe content was due to charge transfer between the CoO{sub 2} and the RS layers. • Total energy calculation showed energetically favorable Fe substitution in the RS layer.

  19. Unresolved fine-scale structure in solar coronal loop-tops

    SciTech Connect (OSTI)

    Scullion, E.; Van der Voort, L. Rouppe; Wedemeyer, S.; Antolin, P.

    2014-12-10

    New and advanced space-based observing facilities continue to lower the resolution limit and detect solar coronal loops in greater detail. We continue to discover even finer substructures within coronal loop cross-sections, in order to understand the nature of the solar corona. Here, we push this lower limit further to search for the finest coronal loop substructures, through taking advantage of the resolving power of the Swedish 1 m Solar Telescope/CRisp Imaging Spectro-Polarimeter (CRISP), together with co-observations from the Solar Dynamics Observatory/Atmospheric Image Assembly (AIA). High-resolution imaging of the chromospheric H? 656.28 nm spectral line core and wings can, under certain circumstances, allow one to deduce the topology of the local magnetic environment of the solar atmosphere where its observed. Here, we study post-flare coronal loops, which become filled with evaporated chromosphere that rapidly condenses into chromospheric clumps of plasma (detectable in H?) known as a coronal rain, to investigate their fine-scale structure. We identify, through analysis of three data sets, large-scale catastrophic cooling in coronal loop-tops and the existence of multi-thermal, multi-stranded substructures. Many cool strands even extend fully intact from loop-top to footpoint. We discover that coronal loop fine-scale strands can appear bunched with as many as eight parallel strands within an AIA coronal loop cross-section. The strand number density versus cross-sectional width distribution, as detected by CRISP within AIA-defined coronal loops, most likely peaks at well below 100 km, and currently, 69% of the substructure strands are statistically unresolved in AIA coronal loops.

  20. Composite Fermions and the First-Landau-Level Fine Structure of the Fractional Quantum Hall Effect

    E-Print Network [OSTI]

    Haxton, W C

    2015-01-01

    We show that an alternative use of operators introduced in 1996 by Ginocchio and Haxton (GH) leads to a simple representation of the wave functions for the fractional quantum Hall effect, as non-interacting quasi-electrons (or composite fermions) fully filling fine-structure subshells within the first Landau level (FLL). In the present GH2 construction each shell corresponds to a distinct quasi-electron, constructed explicitly on both the sphere and the plane as vector products of spinors creating an electron and one unit of magnetic flux, a structure we argue follows from the coordinate scale invariance of the Coulomb potential. The quasi-electrons are eigenstates of angular momentum L and Lz. The hierarchy and conjugate states are the lowest-energy filled-shell configurations of these quasi-electrons, where the energy "counting" is related to Haldane's pseudo-potential. The construction yields a correspondence between the quasi-particle representation of the incompressible FLL state of filling p/(2p +1) and...

  1. Fine-Scale Population Genetic Structure of Two Dioecious Indian Keystone Species, Ficus hispida and Ficus exasperata (Moraceae)

    E-Print Network [OSTI]

    Borges, Renee M

    Fine-Scale Population Genetic Structure of Two Dioecious Indian Keystone Species, Ficus hispida ABSTRACT Although Ficus (Moraceae) is a keystone plant genus in the tropics, providing resources to many at lower densities, play an important role in the functioning of the forest, e.g., keystone species (Dick

  2. DISCOVERY OF FINELY STRUCTURED DYNAMIC SOLAR CORONA OBSERVED IN THE Hi-C TELESCOPE

    SciTech Connect (OSTI)

    Winebarger, Amy R.; Cirtain, Jonathan; Savage, Sabrina; Alexander, Caroline; Golub, Leon; DeLuca, Edward; Schuler, Timothy

    2014-05-20

    In the Summer of 2012, the High-resolution Coronal Imager (Hi-C) flew on board a NASA sounding rocket and collected the highest spatial resolution images ever obtained of the solar corona. One of the goals of the Hi-C flight was to characterize the substructure of the solar corona. We therefore examine how the intensity scales from AIA resolution to Hi-C resolution. For each low-resolution pixel, we calculate the standard deviation in the contributing high-resolution pixel intensities and compare that to the expected standard deviation calculated from the noise. If these numbers are approximately equal, the corona can be assumed to be smoothly varying, i.e., have no evidence of substructure in the Hi-C image to within Hi-C's ability to measure it given its throughput and readout noise. A standard deviation much larger than the noise value indicates the presence of substructure. We calculate these values for each low-resolution pixel for each frame of the Hi-C data. On average, 70% of the pixels in each Hi-C image show no evidence of substructure. The locations where substructure is prevalent is in the moss regions and in regions of sheared magnetic field. We also find that the level of substructure varies significantly over the roughly 160 s of the Hi-C data analyzed here. This result indicates that the finely structured corona is concentrated in regions of heating and is highly time dependent.

  3. Bound on the variation in the fine structure constant implied by Oklo data

    E-Print Network [OSTI]

    Hamdan, Leila

    2015-01-01

    Dynamical models of dark energy can imply that the fine structure constant $\\alpha$ varies over cosmological time scales. Data on shifts in resonance energies $E_r$ from the Oklo natural fission reactor have been used to place restrictive bounds on the change in $\\alpha$ over the last 1.8 billion years. We review the uncertainties in these analyses, focussing on corrections to the standard estimate of $k_\\alpha\\!=\\!\\alpha\\,dE_r/d\\alpha$ due to Damour and Dyson. Guided, in part, by the best practice for assessing systematic errors in theoretical estimates spelt out by Dobaczewski et al. [in J. Phys. G: Nucl. Part. Phys. 41, 074001 (2014)], we compute these corrections in a variety of models tuned to reproduce existing nuclear data. Although the net correction is uncertain to within a factor of 2 or 3, it constitutes at most no more than 25% of the Damour-Dyson estimate of $k_\\alpha$. Making similar allowances for the uncertainties in the modeling of the operation of the Oklo reactors, we conclude that the rela...

  4. The fine structure of the entanglement entropy in the classical XY model

    E-Print Network [OSTI]

    Li-Ping Yang; Yuzhi Liu; Haiyuan Zou; Z. Y. Xie; Y. Meurice

    2015-07-13

    We compare two calculations of the particle density in the superfluid phase of the classical XY model with a chemical potential $\\mu$ in 1+1 dimensions.The first relies on exact blocking formulas from the Tensor Renormalization Group (TRG) formulation of the transfer matrix. The second is a worm algorithm. We show that the particle number distributions obtained with the two methods agree well. We use the TRG method to calculate the thermal entropy and the entanglement entropy. We describe the particle density, the two entropies and the topology of the world lines as we increase $\\mu$ to go across the superfluid phase between the first two Mott insulating phases. For a sufficiently large temporal size, this process reveals an interesting fine structure: the average particle number and the winding number of most of the world lines in the Euclidean time direction increase by one unit at a time. At each step, the thermal entropy develops a peak and the entanglement entropy increases until we reach half-filling and then decreases in a way that approximately mirror the ascent. This suggests an approximate fermionic picture.

  5. Bohr - Planck quantum theory, (Tesla) magnetic monopoles and fine structure constant

    E-Print Network [OSTI]

    Vladan Pankovic; Darko V. Kapor; Stevica Djurovic; Miodrag Krmar

    2014-10-17

    In this work we apply Bohr-Planck (Old quantum atomic and radiation) theory, i.e. and quasi-classical methods for analysis of the magnetic monopoles and other problems. We reproduce exactly some basic elements of the Dirac magnetic monopoles theory, especially Dirac electric/magnetic charge quantization condition. Also, we suggest a new, effective, simply called Tesla model (for analogy with positions of the solenoids by Tesla inductive motor) of the magnetic monopole instead of usual effective Dirac model (half-infinite, very tinny solenoid) of the magnetic monopole. In our, i.e. Tesla model we use three equivalent tiny solenoids connected in series with a voltage source. One end of any solenoid is placed at the circumference of a circle and solenoids are directed radial toward circle center. Length of any solenoid is a bit smaller than finite circle radius so that other end of any solenoid is very close to the circle center. Angles between neighboring solenoids equal $120^{\\circ}$. All this implies that, practically, there is no magnetic field, or, magnetic pole, e.g. $S$, in the circle center, and that whole system holds only other, $N$ magnetic pole, at the ends of the solenoids at circle circumference. Finally, we reproduce relatively satisfactory value of the fine structure constant using Planck, i.e. Bose-Einstein statistics and Wien displacement law.

  6. Atomic structure of machined semiconducting chips: An x-ray absorption spectroscopy study

    SciTech Connect (OSTI)

    Paesler, M.; Sayers, D.

    1988-12-01

    X-ray absorption spectroscopy (XAS) has been used to examine the atomic structure of chips of germanium that were produced by single point diamond machining. It is demonstrated that although the local (nearest neighbor) atomic structure is experimentally quite similar to that of single crystal specimens information from more distant atoms indicates the presence of considerable stress. An outline of the technique is given and the strength of XAS in studying the machining process is demonstrated.

  7. Flare processes evolution and polarization changes of fine structures of solar radio emission in the April 11, 2013 event

    E-Print Network [OSTI]

    Chernov, Gennady; Tan, Baolin; Yan, Yihua; Tan, Chengming; Fu, Qijun; Karlicky, Marian; Fomichev, Valery

    2015-01-01

    The measurement of positions and sizes of radio sources in the observations of solar radio spectral fine structures in an M6.5 flare on April 11, 2013 were observed simultaneously by several radio instruments at four different observatories: Chinese Solar Broadband Radio Spectrometers at Huairou (SBRS/Huairou), Ondrejov Radio spectrograph in the Czech Republic (ORSC/Ondrejov), Badary Broadband Microwave spectropolarimeter (BMS/Irkutsk), and spectrograph/IZMIRAN (Moscow, Troitsk). The fine structures include microwave zebra patterns (ZP), fast pulsations, and fibers. They were observed during the flare brightening located at the tops of a loop arcade. The dynamics of the polarization was associated with the motion of the flare exciter, which was observed in EUV images at 171A and 131A (SDO/AIA). Combining magnetograms observed by the SDO Helioseismic and Magnetic Imager (HMI) with the homologous assumption of EUV flare brightening and ZP bursts, we deduced that the observed ZPs correspond to the ordinary radio...

  8. X-ray absorption study of the electronic structure of Mn-doped amorphous Si

    SciTech Connect (OSTI)

    Arenholz, Elke; Zeng, Li; Huegel, A.; Helgren, E.; Hellman, F.; Piamonteze, C.; Arenholz, E.

    2008-03-08

    The electronic structure of Mn in amorphous Si (a-Mn{sub x}Si{sub 1?x}) is studied by X-ray absorption spectroscopy at the Mn L{sub 3,2} edges for x = 0.005-0.18. Except the x = 0.005 sample, which shows a slight signature of Mn{sup 2+} atomic multiplets associated with a local Mn moment, all samples have broad and featureless L{sub 3,2} absorption peaks, corresponding to an itinerant state for all 3d electrons. The broad X-ray absorption spectra exclude the possibility of a localized 3d moment and explain the unexpectedly quenched Mn moment in this magnetically-doped amorphous semiconductor. Such a fully delocalized d state of Mn dopant in Si has not been previously suggested.

  9. Structural color printing based on plasmonic metasurfaces of perfect light absorption

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Cheng, Fei; Gao, Jie; Luk, Ting S.; Yang, Xiaodong

    2015-06-05

    Subwavelength structural color filtering and printing technologies employing plasmonic nanostructures have recently been recognized as an important and beneficial complement to the traditional colorant-based pigmentation. However, the color saturation, brightness and incident angle tolerance of structural color printing need to be improved to meet the application requirement. Here we demonstrate a structural color printing method based on plasmonic metasurfaces of perfect light absorption to improve color performances such as saturation and brightness. Thin-layer perfect absorbers with periodic hole arrays are designed at visible frequencies and the absorption peaks are tuned by simply adjusting the hole size and periodicity. Near perfectmore »light absorption with high quality factors are obtained to realize high-resolution, angle-insensitive plasmonic color printing with high color saturation and brightness. Moreover, the fabricated metasurfaces can be protected with a protective coating for ambient use without degrading performances. The demonstrated structural color printing platform offers great potential for applications ranging from security marking to information storage.« less

  10. Size-dependent lattice structure of palladium studied by x-ray absorption spectroscopy Chih-Ming Lin,1,

    E-Print Network [OSTI]

    Chen, Yang-Yuan

    Size-dependent lattice structure of palladium studied by x-ray absorption spectroscopy Chih palladium particles, along with bulk material as reference. With decreasing particle size, the extended x and related properties in substrate-free palladium nanoparticles by x-ray absorption spectroscopy XAS mea

  11. The $g$-factor of light ions for an improved determination of the fine-structure constant

    E-Print Network [OSTI]

    Yerokhin, V A; Harman, Z; Tupitsyn, I I; Keitel, C H

    2015-01-01

    A weighted difference of the $g$-factors of the H- and Li-like ions of the same element is theoretically studied and optimized in order to maximize the cancelation of nuclear effects between the two charge states. We show that this weighted difference and its combination for two different elements can be used to extract the fine-structure constant from near-future bound-electron $g$-factor experiments with an accuracy improvement by orders of magnitude as compared to its present literature value.

  12. Solar abundances and helioseismology: fine structure spacings and separation ratios of low-degree p modes

    E-Print Network [OSTI]

    Sarbani Basu; William J. Chaplin; Yvonne Elsworth; Roger New; Aldo M. Serenelli; Graham A. Verner

    2006-10-02

    We have used 4752 days of data collected by the Birmingham Solar-Oscillations Network (BiSON) to determine very precise oscillation frequencies of acoustic low-degree modes that probe the solar core. We compare the fine (small frequency) spacings and frequency separation ratios formed from these data with those of different solar models. We find that models constructed with low metallicity are incompatible with the observations. The results provide strong support for lowering the theoretical uncertainties on the neutrino fluxes. These uncertainties had recently been raised due to the controversy over the solar abundances.

  13. Constraining possible variations of the fine structure constant in strong gravitational fields with the K? iron line

    SciTech Connect (OSTI)

    Bambi, Cosimo, E-mail: bambi@fudan.edu.cn [Center for Field Theory and Particle Physics and Department of Physics, Fudan University, 220 Handan Road, Shanghai, 200433 China (China)

    2014-03-01

    In extensions of general relativity and in theories aiming at unifying gravity with the forces of the Standard Model, the value of the ''fundamental constants'' is often determined by the vacuum expectation value of new fields, which may thus change in different backgrounds. Variations of fundamental constants with respect to the values measured today in laboratories on Earth are expected to be more evident on cosmological timescales and/or in strong gravitational fields. In this paper, I show that the analysis of the K? iron line observed in the X-ray spectrum of black holes can potentially be used to probe the fine structure constant ? in gravitational potentials relative to Earth of ?? ? 0.1. At present, systematic effects not fully under control prevent to get robust and stringent bounds on possible variations of the value of ? with this technique, but the fact that current data can be fitted with models based on standard physics already rules out variations of the fine structure constant larger than some percent.

  14. Three Dimensional Mapping of Nicle Oxidation States Using Full Field Xray Absorption Near Edge Structure Nanotomography

    SciTech Connect (OSTI)

    Nelson, G.J.; Chu, Y.; Harris, W.M.; Izzo, J.R.; Grew, K.N., Chiu, W.K.S.; Yi, J.; Andrews, J.C.; Liu, Y., Pierro, P.

    2011-04-28

    The reduction-oxidation cycling of the nickel-based oxides in composite solid oxide fuel cells and battery electrodes is directly related to cell performance. A greater understanding of nickel redox mechanisms at the microstructural level can be achieved in part using transmission x-ray microscopy (TXM) to explore material oxidation states. X-ray nanotomography combined with x-ray absorption near edge structure (XANES) spectroscopy has been applied to study samples containing distinct regions of nickel and nickel oxide (NiO) compositions. Digitally processed images obtained using TXM demonstrate the three-dimensional chemical mapping and microstructural distribution capabilities of full-field XANES nanotomography.

  15. Distribution of Fine Roots of Ponderosa Pine and Douglas-Fir in a Central Idaho Forest

    E-Print Network [OSTI]

    Fried, Jeremy S.

    at a study site in a central Idaho forest. Concentration and content of fine roots extracted from soil cores of exotic dis- eases, heavy grazing, and timber harvest has altered forest structure, stand composition(SwezyandAgee1991,Dumm2003).Finerootsarecritical structures for water and nutrient absorption from the soil

  16. On the importance of nuclear quantum motions in near edge x-ray absorption fine structure (NEXAFS) spectroscopy of molecules

    SciTech Connect (OSTI)

    Schwartz, Craig P.; Uejio, Janel S.; Saykally, Richard J.; Prendergast, David

    2009-02-26

    We report the effects of sampling nuclear quantum motion with path integral molecular dynamics (PIMD) on calculations of the nitrogen K-edge spectra of two isolated organic molecules. S-triazine, a prototypical aromatic molecule occupying primarily its vibrational ground state at room temperature, exhibits substantially improved spectral agreement when nuclear quantum effects are included via PIMD, as compared to the spectra obtained from either a single fixed-nuclei based calculation or from a series of configurations extracted from a classical molecular dynamics trajectory. Nuclear quantum dynamics can accurately explain the intrinsic broadening of certain features. Glycine, the simplest amino acid, is problematic due to large spectral variations associated with multiple energetically accessible conformations at the experimental temperature. This work highlights the sensitivity of NEXAFS to quantum nuclear motions in molecules, and the necessity of accurately sampling such quantum motion when simulating their NEXAFS spectra.

  17. Quick extended x-ray absorption fine structure instrument with millisecond time scale, optimized for in situ applications

    E-Print Network [OSTI]

    Sparks, Donald L.

    . Wang,4 A. I. Frenkel,4 N. Marinkovic,5 N. Hould,5 M. Ginder-Vogel,5 G. L. Landrot,5 D. L. Sparks,5

  18. Product fine-structure resolved photodissociation dynamics: The A band of H{sub 2}O

    SciTech Connect (OSTI)

    Zhou, Linsen [Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China)] [Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China); Xie, Daiqian, E-mail: dqxie@nju.edu.cn, E-mail: hguo@unm.edu [Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China) [Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China); Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Sun, Zhigang [State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)] [State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Guo, Hua, E-mail: dqxie@nju.edu.cn, E-mail: hguo@unm.edu [Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131 (United States)] [Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131 (United States)

    2014-01-14

    The photodissociation dynamics of H{sub 2}O in its first absorption band is investigated on an accurate potential energy surface based on a large number of high-level ab initio points. Several ro-vibrational states of the parent molecule are considered. Different from most previous theoretical studies, the spin-orbit and ?-doublet populations of the open-shell OH fragment are reported from full-dimensional wave packet calculations. The populations of the two spin-orbit manifolds are in most cases close to the statistical limit, but the ?-doublet is dominated by the A{sup ?} component, thanks largely to the fast in-plane dissociation of H{sub 2}O(A{sup ~1}A{sup ??}). Comparisons with experimental data and a Franck-Condon model are generally very good, although some discrepancies exist.

  19. Precision Test of Many-Body QED in the Be$^+$ $2p$ Fine Structure Doublet Using Short-Lived Isotopes

    E-Print Network [OSTI]

    Nörtershäuser, Wilfried; Krieger, Andreas; Pachucki, Krzysztof; Puchalski, Mariusz; Blaum, Klaus; Bissell, Mark L; Frömmgen, Nadja; Hammen, Michael; Kowalska, Magdalena; Krämer, Jörg; Kreim, Kim; Neugart, Rainer; Neyens, Gerda; Sánchez, Rodolfo; Yordanov, Deyan T

    2015-01-01

    Absolute transition frequencies of the $2s\\; ^2{\\rm S}_{1/2} \\rightarrow 2p\\;^2\\mathrm{P}_{1/2,3/2}$ transitions in Be$^+$ were measured for the isotopes $^{7,9-12}$Be. The fine structure splitting of the $2p$ state and its isotope dependence are extracted and compared to results of \\textit{ab initio} calculations using explicitly correlated basis functions, including relativistic and quantum electrodynamics effects at the order of $m \\alpha^6$ and $m \\alpha^7 \\ln \\alpha$. Accuracy has been improved in both the theory and experiment by 2 orders of magnitude, and good agreement is observed. This represents one of the most accurate tests of quantum electrodynamics for many-electron systems, being insensitive to nuclear uncertainties.

  20. Energy-Tunable Quantum Dot with Minimal Fine Structure Created by Using Simultaneous Electric and Magnetic Fields

    E-Print Network [OSTI]

    M. A. Pooley; A. J. Bennett; R. M. Stevenson; A. J. Shields; I. Farrer; D. A. Ritchie

    2015-07-28

    The neutral biexciton cascade of single quantum dots is a promising source of entangled photon pairs. The character of the entangled state is determined by the energy difference between the excitonic eigenstates known as fine-structure splitting (FSS). Here we reduce the magnitude of the FSS by simultaneously using two independent tuning mechanisms: in-plane magnetic field and vertical electric field. We observe that there exists a minimum possible FSS in each quantum dot which is independent of these tuning mechanisms. However, with simultaneous application of electric and magnetic fields, we show the FSS can be reduced to its minimum value as the energy of emission is tuned over several meV with a 5-T magnet.

  1. AN INTRIGUING CHROMOSPHERIC JET OBSERVED BY HINODE: FINE STRUCTURE KINEMATICS AND EVIDENCE OF UNWINDING TWISTS

    SciTech Connect (OSTI)

    Liu Wei; Berger, Thomas E.; Title, Alan M.; Tarbell, Theodore D. [Lockheed Martin Solar and Astrophysics Laboratory, Department ADBS, Building 252, 3251 Hanover Street, Palo Alto, CA 94304 (United States)

    2009-12-10

    We report a chromospheric jet lasting for more than 1 hr observed by the Hinode Solar Optical Telescope in unprecedented detail. The ejection occurred in three episodes separated by 12-14 minutes, with the amount and velocity of material decreasing with time. The upward velocities range from 438 to 33 km s{sup -1}, while the downward velocities of the material falling back have smaller values (mean: -56km s{sup -1}) and a narrower distribution (standard deviation: 14km s{sup -1}). The average acceleration inferred from parabolic spacetime tracks is 141 m s{sup -2}, a fraction of the solar gravitational acceleration. The jet consists of fine threads (0.''5-2'' wide), which exhibit coherent, oscillatory transverse motions perpendicular to the jet axis and about a common equilibrium position. These motions propagate upward along the jet, with the maximum phase speed of 744+-11 km s{sup -1}at the leading front of the jet. The transverse oscillation velocities range from 151 to 26 km s{sup -1}, amplitudes from 6.0 to 1.9 Mm, and periods from 250 to 536 s. The oscillations slow down with time and cease when the material starts to fall back. The falling material travels along almost straight lines in the original direction of ascent, showing no transverse motions. These observations are consistent with the scenario that the jet involves untwisting helical threads, which rotate about the axis of a single large cylinder and shed magnetic helicity into the upper atmosphere.

  2. Fine scale structural variants distinguish the genomes of Drosophilia melanogaster and D. pseudoobscura

    E-Print Network [OSTI]

    Macdonald, Stuart J.

    2006-07-07

    Background: A primary objective of comparative genomics is to identify genomic elements of functional significance that contribute to phenotypic diversity. Complex changes in genome structure (insertions, duplications, rearrangements, translocations...

  3. Characterization of the Electronic Structure of Silicon Nanoparticles Using X-ray Absorption and Emission

    SciTech Connect (OSTI)

    Vaverka, A M

    2008-07-15

    Resolving open questions regarding transport in nanostructures can have a huge impact on a broad range of future technologies such as light harvesting for energy. Silicon has potential to be used in many of these applications. Understanding how the band edges of nanostructures move as a function of size, surface termination and assembly is of fundamental importance in understanding the transport properties of these materials. In this thesis work I have investigated the change in the electronic structure of silicon nanoparticle assemblies as the surface termination is changed. Nanoparticles are synthesized using a thermal evaporation technique and sizes are determined using atomic force microscopy (AFM). By passivating the particles with molecules containing alcohol groups we are able to modify the size dependent band edge shifts. Both the valence and conduction bands are measured using synchrotron based x-ray absorption spectroscopy (XAS) and soft x-ray fluorescence (SXF) techniques. Particles synthesized via recrystallization of amorphous silicon/SiO{sub 2} multilayers of thicknesses below 10 nm are also investigated using the synchrotron techniques. These samples also show quantum confinement effects but the electronic structure is different from those synthesized via evaporation methods. The total bandgap is determined for all samples measured. The origins of these differences in the electronic structures are discussed.

  4. Vanishing fine structure splittings in telecom wavelength quantum dots grown on (111)A surfaces by droplet epitaxy

    E-Print Network [OSTI]

    X. Liu; N. Ha; H. Nakajima; T. Mano; T. Kuroda; B. Urbaszek; H. Kumano; I. Suemune; Y. Sakuma; K. Sakoda

    2014-06-18

    The emission cascade of a single quantum dot is a promising source of entangled photons. A prerequisite for this source is the use of a symmetric dot analogous to an atom in a vacuum, but the simultaneous achievement of structural symmetry and emission in a telecom band poses a challenge. Here we report the growth and characterization of highly symmetric InAs/InAlAs quantum dots self-assembled on C3v symmetric InP(111)A. The broad emission spectra cover the O (1.3 micron-m), C (1.55 micron-m), and L (1.6 micron-m) telecom bands. The distribution of the fine-structure splittings is considerably smaller than those reported in previous works on dots at similar wavelengths. The presence of dots with degenerate exciton lines is further confirmed by the optical orientation technique. Thus, our dot systems are expected to serve as efficient entangled photon emitters for long-distance fiber-based quantum key distribution.

  5. Fine Structure Due to DonorAcceptor Pair Luminescence in Compensated Si Michio Tajima, Takaaki Iwai, Hiroyuki Toyota, Simona Binetti1

    E-Print Network [OSTI]

    Science/JAXA, Sagamihara 252-5210, Japan 1 CNISM and Department of Material Science, University of Milano materials, called ``solar- grade Si (SOG-Si)'', has been urgently needed for the mass production of solar A fine structure on the higher energy side of donor­acceptor (DA) pair luminescence at 4.2 K has been

  6. Umbral Fine Structures in Sunspots Observed with Hinode Solar Optical Telescope

    E-Print Network [OSTI]

    Reizaburo Kitai; Hiroko Watanabe; Tahei Nakamura; Ken-ichi Otsuji; Takuma Matsumoto; Satoru UeNo; Shin-ichi Nagata; Kazunari Shibata; Richard Muller; Kiyoshi Ichimoto; Saku Tsuneta; Yoshinori Suematsu; Yukio Katsukawa; Toshifumi Shimizu; Theodore D. Tarbell; Richard A. Shine; Alan M. Title; Bruce W. Lites

    2007-11-21

    High resolution imaging observation of a sunspot umbra was done with Hinode Solar Optical Telescope (SOT). Filtergrams in wavelengths of blue and green continuum were taken during three consecutive days. The umbra consisted of a dark core region, several diffuse components and numerous umbral dots. We derived basic properties of umbral dots (UDs), especially their temperatures, lifetimes, proper motions, spatial distribution and morphological evolution. Brightness of UDs is confirmed to depend on the brightness of their surrounding background. Several UDs show fission and fusion. Thanks to the stable condition of space observation, we could first follow the temporal behavior of these events. The derived properties of internal structure of the umbra are discussed in viewpoint of magnetoconvection in a strong magnetic field.

  7. Fine Magnetic Structure and Origin of Counter-Streaming Mass Flows in a Quiescent Solar Prominence

    E-Print Network [OSTI]

    Shen, Yuandeng; Liu, Ying D; Chen, P F; Su, Jiangtao; Xu, Zhi; Liu, Zhong

    2015-01-01

    We present high-resolution observations of a quiescent solar prominence which was consisted of a vertical and a horizontal foot encircled by an overlying spine, and counter-streaming mass flows were ubiquitous in the prominence. While the horizontal foot and the spine were connecting to the solar surface, the vertical foot was suspended above the solar surface and supported by a semicircular bubble structure. The bubble first collapsed and then reformed at a similar height, finally, it started to oscillate for a long time. We find that the collapsing and oscillation of the bubble boundary were tightly associated with a flare-like feature located at the bottom of the bubble. Based on the observational results, we propose that the prominence should be composed of an overlying horizontal spine encircling a low-lying horizontal and a vertical foot, in which the horizontal foot was consisted of shorter field lines running partially along the spine and with the both ends connecting to the solar surface, while the v...

  8. Dark energy and Equivalence Principle constraints from astrophysical tests of the stability of the fine-structure constant

    E-Print Network [OSTI]

    C. J. A. P. Martins; A. M. M. Pinho; R. F. C. Alves; M. Pino; C. I. S. A. Rocha; M. von Wietersheim

    2015-08-25

    Astrophysical tests of the stability of fundamental couplings, such as the fine-structure constant $\\alpha$, are becoming an increasingly powerful probe of new physics. Here we discuss how these measurements, combined with local atomic clock tests and Type Ia supernova and Hubble parameter data, constrain the simplest class of dynamical dark energy models where the same degree of freedom is assumed to provide both the dark energy and (through a dimensionless coupling, $\\zeta$, to the electromagnetic sector) the $\\alpha$ variation. Specifically, current data tightly constrains a combination of $\\zeta$ and the present dark energy equation of state $w_0$. Moreover, in these models the new degree of freedom inevitably couples to nucleons (through the $\\alpha$ dependence of their masses) and leads to violations of the Weak Equivalence Principle. We obtain indirect bounds on the E\\"otv\\"os parameter $\\eta$ that are typically stronger than the current direct ones. We discuss the model-dependence of our results and briefly comment on how the forthcoming generation of high-resolution ultra-stable spectrographs will enable significantly tighter constraints.

  9. Electronic structure of lanthanum copper oxychalcogenides LaCuOCh (Ch=S, Se, Te) by X-ray photoelectron and absorption spectroscopy

    SciTech Connect (OSTI)

    Rudyk, Brent W.; Blanchard, Peter E.R.; Cavell, Ronald G. [Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2 (Canada); Mar, Arthur, E-mail: arthur.mar@ualberta.ca [Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2 (Canada)

    2011-07-15

    X-ray photoelectron spectroscopy (XPS) and X-ray absorption near-edge spectroscopy (XANES) have been applied to examine the electronic structures of lanthanum copper oxychalcogenides LaCuOCh (Ch=S, Se, Te), whose structure has been conventionally viewed as consisting of nominally isolated [LaO] and [CuCh] layers. However, there is evidence for weak La-Ch interactions between these layers, as seen in small changes in the satellite intensity of the La 3d XPS spectra as the chalcogen is changed and as supported by band structure calculations. The O 1s and Cu 2p XPS spectra are insensitive to chalcogen substitution. Lineshapes in the Cu 2p XPS spectra and fine-structure in the Cu L- and M-edge XANES spectra support the presence of Cu{sup +} species. The Ch XPS spectra show negative BE shifts relative to the elemental chalcogen, indicative of anionic species; these shifts correlate well with greater difference in electronegativity between the Cu and Ch atoms, provided that an intermediate electronegativity is chosen for Se. - Graphical abstract: The presence of anionic chalcogen atoms in LaCuOCh is supported by the Ch binding energies, which undergo negative shifts proportional to the polarity of the Cu-Ch bonds. Highlights: > La 3d XPS confirms La-Ch interlayer interactions between [LaO] and [CuCh] layers. > O 1s and Cu 2p XPS are insensitive to chalcogen substitution. > Cu XANES spectra support the presence of Cu{sup +} species. > Negative shifts in Ch binding energies imply anionic chalcogen atoms.

  10. Electronic structure of liquid water from polarization-dependent two-photon absorption spectroscopy

    E-Print Network [OSTI]

    Elles, Christopher G.; Rivera, Christopher A.; Zhang, Yuyuan; Pieniazek, Piotr A.; Bradforth, Stephen E.

    2009-02-26

    and connects the 2PA spectrum with previous one-photon absorption, photoelectron, and x-ray absorptionspectroscopy measurements of liquid water. Previously unresolved, overlapping transitions are assigned for the first time. Finally, the electronic character...

  11. Structural stability of 1100{degree}C heated Pd/k during absorption cycling in protium

    SciTech Connect (OSTI)

    Fisher, I.A.

    1993-03-12

    Pd/k is a hydride forming packing material which is used in the Thermal Cycling Absorption Process (TCAP). Palladium is supported on kieselguhr to create a packing material which will provide adequate void space to prevent excessive pressure drops and flow restrictions. The use of unsupported palladium would result in blockage of columns and clogging of filters due to the small particle size of unsupported palladium hydride powder. During pilot scale demonstrations, it was noted that the Pd/k packing material had degraded causing severe flow restrictions within the TCAP column. A solution to the problem involved the heating of Pd/k at 1,110{degree}C to strengthen the packing material, and render it more resistant to breakdown. The 1, 100{degree}C heated Pd/k has been shown to be more resistant to mechanical breakdown than the Pd/k prior to heat treatment. Two primary modes of Pd/k particle degradation have been identified: mechanical breakdown caused by particle fluidization and degradation caused by absorption/desorption cycling. Absorption/desorption cycling causes the palladium particles within the packing to expanded and contract upon formation and decomposition of the hydride, respectively. This expansion and contraction causes large localized stresses within the packing material, which if these stresses can not be accommodated within the packing will cause the material to crack and degrade. The purpose of this report is to document the results of the absorption/desorption cycling of 1,100{degree}C heated Pd/k and compare these results to the results obtained from the absorption/desorption cycling of Pd/k which had not been heated at 1, 100{degree}C.

  12. Three-dimensional mapping of nickel oxidation states using full field x-ray absorption near edge structure nanotomography

    SciTech Connect (OSTI)

    Nelson, George J.; Harris, William M.; Izzo, John R. Jr.; Grew, Kyle N.; Chiu, Wilson K. S. [HeteroFoaM Center, a DOE Energy Frontier Research Center, Department of Mechanical Engineering, University of Connecticut, 191 Auditorium Rd., Storrs, Connecticut 06269-3139 (United States); Chu, Yong S. [National Synchrotron Light Source II, Brookhaven National Laboratory, Bldg. 703 Upton, New York 11973-5000 (United States); Yi, Jaemock [Advanced Photon Source, Argonne National Laboratory, 9700 S. Cass Ave., Bldg. 438-B007 Argonne, Illinois 60439 (United States); Andrews, Joy C.; Liu Yijin; Pianetta, Piero [Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Rd., MS 69 Menlo Park, California 94025 (United States)

    2011-04-25

    The reduction-oxidation cycling of the nickel-based oxides in composite solid oxide fuel cells and battery electrodes is directly related to cell performance. A greater understanding of nickel redox mechanisms at the microstructural level can be achieved in part using transmission x-ray microscopy (TXM) to explore material oxidation states. X-ray nanotomography combined with x-ray absorption near edge structure (XANES) spectroscopy has been applied to study samples containing distinct regions of nickel and nickel oxide (NiO) compositions. Digitally processed images obtained using TXM demonstrate the three-dimensional chemical mapping and microstructural distribution capabilities of full-field XANES nanotomography.

  13. Relativistic effects in Sr, Dy, YbII and YbIII and search for variation of the fine structure constant

    E-Print Network [OSTI]

    Dzuba, V A; Marchenko, M V

    2003-01-01

    A possibility for fundamental constants to vary in time is suggested by theories unifying gravity with other interactions. In this article we examine proposals to use optical transitions of Sr, Dy, YbII and YbIII for the search of the time variation of the fine structure constant $\\alpha$. Frequencies of atomic transitions are calculated using relativistic Hartree-Fock method and configuration interaction technique. The effect of variation of $\\alpha$ on the frequencies is studied by varying $\\alpha$ in computer codes. Accuracy of measurements needed to improve current best limit on the time variation of $\\alpha$ is discussed.

  14. Nitrogen K-edge x-ray absorption near edge structure of pyrimidine-containing nucleotides in aqueous solution

    SciTech Connect (OSTI)

    Shimada, Hiroyuki Minami, Hirotake; Okuizumi, Naoto; Sakuma, Ichiro; Ukai, Masatoshi; Fujii, Kentaro; Yokoya, Akinari; Fukuda, Yoshihiro; Saitoh, Yuji

    2015-05-07

    X-ray absorption near edge structure (XANES) was measured at energies around the N K-edge of the pyrimidine-containing nucleotides, cytidine 5?-monophosphate (CMP), 2?-deoxythymidine 5?-monophosphate (dTMP), and uridine 5?-monophosphate (UMP), in aqueous solutions and in dried films under various pH conditions. The features of resonant excitations below the N K-edge in the XANES spectra for CMP, dTMP, and UMP changed depending on the pH of the solutions. The spectral change thus observed is systematically explained by the chemical shift of the core-levels of N atoms in the nucleobase moieties caused by structural changes due to protonation or deprotonation at different proton concentrations. This interpretation is supported by the results of theoretical calculations using density functional theory for the corresponding nucleobases in the neutral and protonated or deprotonated forms.

  15. Utilization of Structured Packing for Energy Savings in Distillation and Absorption Columns 

    E-Print Network [OSTI]

    Berven, O. J.; Howard, W. E.

    1986-01-01

    As the need to reduce production costs causes manufacturers to re-evaluate processing schemes, high efficiency structured packings are increasingly recognized as an effective alternative for reducing energy consumption in ...

  16. 3D Imaging of Nickel Oxidation States using Full Field X-ray Absorption Near Edge Structure Nanotomography

    SciTech Connect (OSTI)

    Nelson, George; Harris, William; Izzo, John; Grew, Kyle N.

    2012-01-20

    Reduction-oxidation (redox) cycling of the nickel electrocatalyst phase in the solid oxide fuel cell (SOFC) anode can lead to performance degradation and cell failure. A greater understanding of nickel redox mechanisms at the microstructural level is vital to future SOFC development. Transmission x-ray microscopy (TXM) provides several key techniques for exploring oxidation states within SOFC electrode microstructure. Specifically, x-ray nanotomography and x-ray absorption near edge structure (XANES) spectroscopy have been applied to study samples of varying nickel (Ni) and nickel oxide (NiO) compositions. The imaged samples are treated as mock SOFC anodes containing distinct regions of the materials in question. XANES spectra presented for the individual materials provide a basis for the further processing and analysis of mixed samples. Images of composite samples obtained are segmented, and the distinct nickel and nickel oxide phases are uniquely identified using full field XANES spectroscopy. Applications to SOFC analysis are discussed.

  17. Helium and Deuterium Abundances as a Test for the Time Variation of the Fine Structure Constant and the Higgs Vacuum Expectation Value

    E-Print Network [OSTI]

    Nidal Chamoun; Susana J. Landau; Mercedes E. Mosquera; Hector Vucetich

    2006-12-21

    We use the semi-analytic method of \\citet{Esma91} to calculate the abundances of Helium and Deuterium produced during Big Bang nucleosynthesis assuming the fine structure constant and the Higgs vacuum expectation value may vary in time. We analyze the dependence on the fundamental constants of the nucleon mass, nuclear binding energies and cross sections involved in the calculation of the abundances. Unlike previous works, we do not assume the chiral limit of QCD. Rather, we take into account the quark masses and consider the one-pion exchange potential, within perturbation theory, for the proton-neutron scattering. However, we do not consider the time variation of the strong interactions scale but attribute the changes in the quark masses to the temporal variation of the Higgs vacuum expectation value. Using the observational data of the helium and deuterium, we put constraints on the variation of the fundamental constants between the time of nucleosynthesis and the present time.

  18. Highly-reduced Fine-structure splitting in InAs/InP quantum dots offering efficient on-demand 1.55 $?$m entangled photon emitter

    E-Print Network [OSTI]

    Lixin He; Ming Gong; Chuan-Feng Li; Guang-Can Guo; Alex Zunger

    2008-06-03

    To generate entangled photon pairs via quantum dots (QDs), the exciton fine structure splitting (FSS) must be comparable to the exciton homogeneous line width. Yet in the (In,Ga)As/GaAs QD, the intrinsic FSS is about a few tens $\\mu$eV. To achieve photon entanglement, it is necessary to Cherry-pick a sample with extremely small FSS from a large number of samples, or to apply strong in-plane magnetic field. Using theoretical modeling of the fundamental causes of FSS in QDs, we predict that the intrinsic FSS of InAs/InP QDs is an order of magnitude smaller than that of InAs/GaAs dots, and better yet, their excitonic gap matches the 1.55 $\\mu$m fiber optic wavelength, therefore offer efficient on-demand entangled photon emitters for long distance quantum communication.

  19. Solar selective absorption coatings

    DOE Patents [OSTI]

    Mahoney, Alan R. (Albuquerque, NM); Reed, Scott T. (Albuquerque, NM); Ashley, Carol S. (Albuquerque, NM); Martinez, F. Edward (Horseheads, NY)

    2003-10-14

    A new class of solar selective absorption coatings are disclosed. These coatings comprise a structured metallic overlayer such that the overlayer has a sub-micron structure designed to efficiently absorb solar radiation, while retaining low thermal emissivity for infrared thermal radiation. A sol-gel layer protects the structured metallic overlayer from mechanical, thermal, and environmental degradation. Processes for producing such solar selective absorption coatings are also disclosed.

  20. Solar selective absorption coatings

    DOE Patents [OSTI]

    Mahoney, Alan R. (Albuquerque, NM); Reed, Scott T. (Albuquerque, NM); Ashley, Carol S. (Albuquerque, NM); Martinez, F. Edward (Horseheads, NY)

    2004-08-31

    A new class of solar selective absorption coatings are disclosed. These coatings comprise a structured metallic overlayer such that the overlayer has a sub-micron structure designed to efficiently absorb solar radiation, while retaining low thermal emissivity for infrared thermal radiation. A sol-gel layer protects the structured metallic overlayer from mechanical, thermal, and environmental degradation. Processes for producing such solar selective absorption coatings are also disclosed.

  1. Electric communication signals retain their fine temporal structure as they are transmitted from signaller to receiver in

    E-Print Network [OSTI]

    Hopkins, Carl D.

    and reverberation (Hopkins, 1986b). This enables weakly electric fish to communicate useful information even with their brief electric organ discharges (EODs). EODs from different species of African mormyrid electric fish). These experiments suggested that the salient feature of the EOD is its temporal waveform structure. Mormyrid fish

  2. THE STRUCTURAL CHEMISTRY OF MOLYBDENUM IN MODEL HIGH LEVEL NUCLEAR WASTE GLASSES, INVESTIGATED BY MO K-EDGE X-RAY ABSORPTION

    E-Print Network [OSTI]

    Sheffield, University of

    THE STRUCTURAL CHEMISTRY OF MOLYBDENUM IN MODEL HIGH LEVEL NUCLEAR WASTE GLASSES, INVESTIGATED of molybdenum in model UK high level nuclear waste glasses was investigated by X-ray Absorption Spectroscopy (XAS). Molybdenum K-edge XAS data were acquired from several inactive simulant high level nuclear waste

  3. Dopant site selectivity in BaCe0.85M0.15O3-by extended x-ray absorption fine structure

    E-Print Network [OSTI]

    Haile, Sossina M.

    solid oxide fuel cells and in hydrogen sensors.1­3 Proton incorporation requires, as a first step compensating defects for dopant ions and which are later exchanged with protons under hydrogen atmospheres lead barium oxide evaporation at high temperatures, en- suring that the overall A:B mole ratio in the ABO3

  4. Structure of epitaxial (Fe,N) codoped rutile TiO2 thin films by x-ray absorption

    SciTech Connect (OSTI)

    Kaspar, Tiffany C.; Ney, A.; Mangham, Andrew N.; Heald, Steve M.; Joly, Yves; Ney, V.; Wilhelm, F.; Rogalev, A.; Yakou, Flora; Chambers, Scott A.

    2012-07-23

    Homoepitaxial thin films of Fe:TiO2 and (Fe,N):TiO2 were deposited on rutile(110) by molecular beam epitaxy. X-ray absorption near edge spectroscopy (XANES) spectra were collected at the Ti L-edge, Fe L-edge, O K-edge, N K-edge, and Ti K-edge. No evidence of structural disorder associated with a high concentration of oxygen vacancies is observed. Substitution of Fe for Ti could not be confirmed, although secondary phase Fe2O3 and metallic Fe can be ruled out. The similarity of the N K-edge spectra to O, and the presence of a strong x-ray linear dichroism (XLD) signal for the N K-edge, indicates that N is substitutional for O in the rutile lattice, and is not present as a secondary phase such as TiN. Simulations of the XANES spectra qualitatively confirm substitution, although N appears to be present in more than one local environment. Neither Fe:TiO2 nor (Fe,N):TiO2 exhibit intrinsic room temperature ferromagnetism, despite the presence of mixed valence Fe(II)/Fe(III) in the reduced (Fe,N):TiO2 film.

  5. An x-ray absorption spectroscopic study of the electronic structure and bonding of rare-earth orthoferrites

    SciTech Connect (OSTI)

    Hayes, J.R.; Grosvenor, A.P. (Saskatchewan)

    2011-11-07

    Rare-earth orthoferrites, REFeO{sub 3} (RE=rare earth; Y), are tremendously adaptable compounds that are being investigated for use in a wide variety of applications including gas sensors, vehicle catalytic converters, and solid-oxide fuel cells. They also exhibit interesting magnetic properties such as high-temperature antiferromagnetism, making them useful for data storage applications. The compounds adopt a distorted perovskite-type structure where the tilt angle of the octahedra increases (Fe-O-Fe bond angle decreases) as the size of the rare-earth atom decreases. Despite intensive study of the physical properties of these compounds, very few studies have investigated how the bonding and electronic structure of these systems change with substitution of the RE. X-ray absorption near-edge spectroscopy (XANES) is a technique well-suited for such a study, and, in view of this, Fe L-, Fe K- and O K-edge spectra from a series of REFeO{sub 3} compounds (RE=La, Pr, Nd, Sm, Eu, Gd, Ho, Yb, Y) have been collected, and are presented here. Fe L-edge spectra show that Fe is octahedrally coordinated and that the Fe-centered octahedra do not appear to distort with changes in the identity of the RE. The Fe K-edge spectra contain an intersite hybrid peak, which is an ill-studied feature that is attributed to non-local transitions of 1s electrons to 3d states on the next-nearest-neighbor atom that are hybridized with 4p states on the absorbing atom through O 2p states. In this study, it is shown that the intensity of this feature is strongly dependent on the Fe-O-Fe bond angle; the lower the Fe-O-Fe bond angle, the less intense the intersite hybrid peak is.

  6. Towards simultaneous measurements of electronic and structural properties in ultra-fast x-ray free electron laser absorption spectroscopy experiments

    SciTech Connect (OSTI)

    Gaudin, J.; Fourment, C.; Cho, B. I.; Engelhorn, K.; Galtier, E.; Harmand, M.; Leguay, P. M.; Lee, H. J.; Nagler, B.; Nakatsutsumi, M.; Ozkan, C.; Störmer, M.; Toleikis, S.; Tschentscher, Th.; Heimann, P. A.; Dorchies, F.

    2014-04-17

    The rapidly growing ultrafast science with X-ray lasers unveils atomic scale processes with unprecedented time resolution bringing the so called “molecular movie” within reach. X-ray absorption spectroscopy is one of the most powerful x-ray techniques providing both local atomic order and electronic structure when coupled with ad-hoc theory. Collecting absorption spectra within few x-ray pulses is possible only in a dispersive setup. We demonstrate ultrafast time-resolved measurements of the LIII-edge x-ray absorption near-edge spectra of irreversibly laser excited Molybdenum using an average of only few x-ray pulses with a signal to noise ratio limited only by the saturation level of the detector. The simplicity of the experimental set-up makes this technique versatile and applicable for a wide range of pump-probe experiments, particularly in the case of non-reversible processes.

  7. Towards simultaneous measurements of electronic and structural properties in ultra-fast x-ray free electron laser absorption spectroscopy experiments

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gaudin, J.; Fourment, C.; Cho, B. I.; Engelhorn, K.; Galtier, E.; Harmand, M.; Leguay, P. M.; Lee, H. J.; Nagler, B.; Nakatsutsumi, M.; et al

    2014-04-17

    The rapidly growing ultrafast science with X-ray lasers unveils atomic scale processes with unprecedented time resolution bringing the so called “molecular movie” within reach. X-ray absorption spectroscopy is one of the most powerful x-ray techniques providing both local atomic order and electronic structure when coupled with ad-hoc theory. Collecting absorption spectra within few x-ray pulses is possible only in a dispersive setup. We demonstrate ultrafast time-resolved measurements of the LIII-edge x-ray absorption near-edge spectra of irreversibly laser excited Molybdenum using an average of only few x-ray pulses with a signal to noise ratio limited only by the saturation level ofmore »the detector. The simplicity of the experimental set-up makes this technique versatile and applicable for a wide range of pump-probe experiments, particularly in the case of non-reversible processes.« less

  8. New Measurement of the Electron Magnetic Moment and the Fine Structure Constant: A First Application of a One-Electron Quantum Cyclotron

    ScienceCinema (OSTI)

    Gabrielse, Gerald [Harvard University, Cambridge, Massachusetts, United States

    2009-09-01

    Remarkably, the famous UW measurement of the electron magnetic moment has stood since 1987. With QED theory, this measurement has determined the accepted value of the fine structure constant. This colloquium is about a new Harvard measurement of these fundamental constants. The new measurement has an uncertainty that is about six times smaller, and it shifts the values by 1.7 standard deviations. One electron suspended in a Penning trap is used for the new measurement, like in the old measurement. What is different is that the lowest quantum levels of the spin and cyclotron motion are resolved, and the cyclotron as well as spin frequencies are determined using quantum jump spectroscopy. In addition, a 0.1 mK Penning trap that is also a cylindrical microwave cavity is used to control the radiation field, to suppress spontaneous emission by more than a factor of 100, to control cavity shifts, and to eliminate the blackbody photons that otherwise stimulate excitations from the cyclotron ground state. Finally, great signal-to-noise for one-quantum transitions is obtained using electronic feedback to realize the first one-particle self-excited oscillator. The new methods may also allow a million times improved measurement of the 500 times small antiproton magnetic moment.

  9. Variational Models for Fine Structures

    E-Print Network [OSTI]

    Schaeffer, Hayden

    2013-01-01

    78] M. Zhou, H. Chen, J. Paisley, L. Ren, G. Sapiro, and L.26] and Zhou, Chen, Paisley, Ren, Sapiro, and Carin [78

  10. Structural stability of 1100[degree]C heated Pd/k during absorption cycling in protium. [Palladium supported on kieselguhr

    SciTech Connect (OSTI)

    Fisher, I.A.

    1993-03-12

    Pd/k is a hydride forming packing material which is used in the Thermal Cycling Absorption Process (TCAP). Palladium is supported on kieselguhr to create a packing material which will provide adequate void space to prevent excessive pressure drops and flow restrictions. The use of unsupported palladium would result in blockage of columns and clogging of filters due to the small particle size of unsupported palladium hydride powder. During pilot scale demonstrations, it was noted that the Pd/k packing material had degraded causing severe flow restrictions within the TCAP column. A solution to the problem involved the heating of Pd/k at 1,110[degree]C to strengthen the packing material, and render it more resistant to breakdown. The 1, 100[degree]C heated Pd/k has been shown to be more resistant to mechanical breakdown than the Pd/k prior to heat treatment. Two primary modes of Pd/k particle degradation have been identified: mechanical breakdown caused by particle fluidization and degradation caused by absorption/desorption cycling. Absorption/desorption cycling causes the palladium particles within the packing to expanded and contract upon formation and decomposition of the hydride, respectively. This expansion and contraction causes large localized stresses within the packing material, which if these stresses can not be accommodated within the packing will cause the material to crack and degrade. The purpose of this report is to document the results of the absorption/desorption cycling of 1,100[degree]C heated Pd/k and compare these results to the results obtained from the absorption/desorption cycling of Pd/k which had not been heated at 1, 100[degree]C.

  11. Fine Grained Robotics

    E-Print Network [OSTI]

    Flynn, Anita M.

    Fine grained robotics is the idea of solving problems utilizing multitudes of very simple machines in place of one large complex entity. Organized in the proper way, simple machines and simple behaviors can lead to emergent ...

  12. Electromagnetic waves reflection, transmission and absorption by graphene - magnetic semiconductor - graphene sandwich-structure in magnetic field: Faraday geometry

    E-Print Network [OSTI]

    Kuzmin, Dmitry A; Shavrov, Vladimir G

    2014-01-01

    Electrodynamic properties of the graphene - magnetic semiconductor - graphene sandwich-structure have been investigated theoretically with taking into account the dissipation processes. Influence of graphene layers on electromagnetic waves propagation in graphene - semi-infinte magnetic semiconductor and graphene - magnetic semiconductor - graphene sandwich-structure has been analyzed. Frequency and field dependences of the reflectance, transmittance and absorbtance of electromagnetic waves by such structure have been calculated. The size effects associated with the thickness of the structure have been analyzed. The possibility of efficient control of electrodynamic properties of graphene - magnetic semiconductor - graphene sandwich structure by an external magnetic field has been shown.

  13. Updated Aug 2010 -DG BACHELOR OF TEACHING (SECONDARY)/BACHELOR OF FINE ART

    E-Print Network [OSTI]

    Fleming, Andrew J.

    Updated Aug 2010 - DG BACHELOR OF TEACHING (SECONDARY)/BACHELOR OF FINE ART Requirements and Structure The Bachelor of Teaching (Secondary)/Bachelor of Fine Art program is offered as a 4 year full time Courses - 210 units · A Fine Art Specialisation - 40 units · Studio Practice in a different area from Fine

  14. Updated Aug 2010 -DG BACHELOR OF TEACHING (SECONDARY)/BACHELOR OF FINE ART

    E-Print Network [OSTI]

    Fleming, Andrew J.

    Updated Aug 2010 - DG BACHELOR OF TEACHING (SECONDARY)/BACHELOR OF FINE ART Requirements and Structure The Bachelor of Teaching (Secondary)/Bachelor of Fine Art program is offered as a 4 year full time Courses - 210 units A Fine Art Specialisation - 40 units Studio Practice in a different area from Fine

  15. Nitrogen K-edge X-ray absorption near edge structure (XANES) spectra of purine-containing nucleotides in aqueous solution

    SciTech Connect (OSTI)

    Shimada, Hiroyuki; Fukao, Taishi; Minami, Hirotake; Ukai, Masatoshi; Fujii, Kentaro; Yokoya, Akinari; Fukuda, Yoshihiro; Saitoh, Yuji

    2014-08-07

    The N K-edge X-ray absorption near edge structure (XANES) spectra of the purine-containing nucleotide, guanosine 5{sup ?}-monophosphate (GMP), in aqueous solution are measured under various pH conditions. The spectra show characteristic peaks, which originate from resonant excitations of N 1s electrons to ?* orbitals inside the guanine moiety of GMP. The relative intensities of these peaks depend on the pH values of the solution. The pH dependence is explained by the core-level shift of N atoms at specific sites caused by protonation and deprotonation. The experimental spectra are compared with theoretical spectra calculated by using density functional theory for GMP and the other purine-containing nucleotides, adenosine 5{sup ?}-monophosphate, and adenosine 5{sup ?}-triphosphate. The N K-edge XANES spectra for all of these nucleotides are classified by the numbers of N atoms with particular chemical bonding characteristics in the purine moiety.

  16. Fluorescence excitation and ultraviolet absorption spectra and theoretical calculations for benzocyclobutane: Vibrations and structure of its excited S{sub 1}(?,?{sup *}) electronic state

    SciTech Connect (OSTI)

    Shin, Hee Won; Ocola, Esther J.; Laane, Jaan; Kim, Sunghwan

    2014-01-21

    The fluorescence excitation spectra of jet-cooled benzocyclobutane have been recorded and together with its ultraviolet absorption spectra have been used to assign the vibrational frequencies for this molecule in its S{sub 1}(?,?{sup *}) electronic excited state. Theoretical calculations at the CASSCF(6,6)/aug-cc-pVTZ level of theory were carried out to compute the structure of the molecule in its excited state. The calculated structure was compared to that of the molecule in its electronic ground state as well as to the structures of related molecules in their S{sub 0} and S{sub 1}(?,?{sup *}) electronic states. In each case the decreased ? bonding in the electronic excited states results in longer carbon-carbon bonds in the benzene ring. The skeletal vibrational frequencies in the electronic excited state were readily assigned and these were compared to the ground state and to the frequencies of five similar molecules. The vibrational levels in both S{sub 0} and S{sub 1}(?,?{sup *}) states were remarkably harmonic in contrast to the other bicyclic molecules. The decreases in the frequencies of the out-of-plane skeletal modes reflect the increased floppiness of these bicyclic molecules in their S{sub 1}(?,?{sup *}) excited state.

  17. Measurement of the absorption coefficient for light laterally propagating in light-emitting diode structures with In{sub 0.2}Ga{sub 0.8}N/GaN quantum wells

    SciTech Connect (OSTI)

    Lelikov, Yu. S.; Bochkareva, N. I.; Gorbunov, R. I.; Martynov, I. A.; Rebane, Yu. T.; Tarkin, D. V.; Shreter, Yu. G. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)], E-mail: YShreter@mail.ioffe.ru

    2008-11-15

    A procedure for measuring the absorption coefficient for light propagating parallel to the surface of a GaN-based light emitting diode chip on a sapphire substrate is suggested. The procedure implies the study of emission from one end face of the chip as the opposite end face is illuminated with a light emitting diode. The absorption coefficient is calculated from the ratio between the intensities of emission emerging from the end faces of the sapphire substrate and the epitaxial layer. From the measurements for chips based on p-GaN/In{sub 0.2}Ga{sub 0.8}N/n-GaN structures, the lateral absorption coefficient is determined at a level of (23 {+-} 3)cm{sup -1} at a wavelength of 465 nm. Possible causes for the discrepancy between the absorption coefficients determined in the study and those reported previously are analyzed.

  18. Ge L{sub 3}-edge x-ray absorption near-edge structure study of structural changes accompanying conductivity drift in the amorphous phase of Ge{sub 2}Sb{sub 2}Te{sub 5}

    SciTech Connect (OSTI)

    Mitrofanov, K. V. [Nanoelectronics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8562 (Japan); Kolobov, A. V., E-mail: a.kolobov@aist.go.jp; Fons, P. [Nanoelectronics Research Institute and Green Nanoelectronics Center, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8562, Japan and Synchrotron Radiation Research Institute (JASRI), SPring-8, 1-1-1, Kouto, Sayo, Hyogo 679-5198 (Japan); Wang, X.; Tominaga, J. [Nanoelectronics Research Institute and Green Nanoelectronics Center, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8562 (Japan); Tamenori, Y.; Uruga, T. [Synchrotron Radiation Research Institute (JASRI), SPring-8, 1-1-1, Kouto, Sayo, Hyogo 679-5198 (Japan); Ciocchini, N.; Ielmini, D. [DEIB - Politecnico di Milano, Piazza L. Da Vinci 32, 20133 Milano (Italy)

    2014-05-07

    A gradual uncontrollable increase in the resistivity of the amorphous phase of phase-change alloys, such as Ge{sub 2}Sb{sub 2}Te{sub 5}, known as drift, is a serious technological issue for application of phase-change memory. While it has been proposed that drift is related to structural relaxation, no direct structural results have been reported so far. Here, we report the results of Ge L{sub 3}-edge x-ray absorption measurements that suggest that the drift in electrical conductivity is associated with the gradual conversion of tetrahedrally coordinated Ge sites into pyramidal sites, while the system still remains in the amorphous phase. Based on electronic configuration arguments, we propose that during this process, which is governed by the existence of lone-pair electrons, the concentration of free carriers in the system decreases resulting in an increase in resistance despite the structural relaxation towards the crystalline phase.

  19. Electronic and atomic structures of Ti{sub 1-x}Al{sub x}N thin films related to their damage behavior

    SciTech Connect (OSTI)

    Tuilier, M.-H.; Pac, M.-J.; Girleanu, M.; Covarel, G.; Arnold, G.; Louis, P.; Rousselot, C.; Flank, A.-M.

    2008-04-15

    Ti and Al K-edge x-ray absorption spectroscopy is used to investigate the electronic structure of Ti{sub 1-x}Al{sub x}N thin films deposited by reactive magnetron sputtering. The experimental near edge spectra of TiN and AlN are interpreted in the light of unoccupied density of state band structure calculations. The comparison of the structural parameters derived from x-ray absorption fine structure and x-ray diffraction reveals segregation between Al-rich and Ti-rich domains within the Ti{sub 1-x}Al{sub x}N films. Whereas x-ray diffraction probes only the crystallized domains, the structural information derived from extended x-ray absorption fine structure analysis turns on both crystalline and grain boundaries. The results are discussed by considering the damage behavior of the films depending on the composition.

  20. Highly-reduced Fine-structure splitting in InAs/InP quantum dots offering efficient on-demand 1.55 $\\mu$m entangled photon emitter

    E-Print Network [OSTI]

    He, Lixin; Li, Chuan-Feng; Guo, Guang-Can; Zunger, Alex

    2008-01-01

    To generate entangled photon pairs via quantum dots (QDs), the exciton fine structure splitting (FSS) must be comparable to the exciton homogeneous line width. Yet in the (In,Ga)As/GaAs QD, the intrinsic FSS is about a few tens $\\mu$eV. To achieve photon entanglement, it is necessary to Cherry-pick a sample with extremely small FSS from a large number of samples, or to apply strong in-plane magnetic field. Using theoretical modeling of the fundamental causes of FSS in QDs, we predict that the intrinsic FSS of InAs/InP QDs is an order of magnitude smaller than that of InAs/GaAs dots, and better yet, their excitonic gap matches the 1.55 $\\mu$m fiber optic wavelength, therefore offer efficient on-demand entangled photon emitters for long distance quantum communication.

  1. A laboratory-based hard x-ray monochromator for high-resolution x-ray emission spectroscopy and x-ray absorption near edge structure measurements

    SciTech Connect (OSTI)

    Seidler, G. T. Mortensen, D. R.; Remesnik, A. J.; Pacold, J. I.; Ball, N. A.; Barry, N.; Styczinski, M.; Hoidn, O. R.

    2014-11-15

    We report the development of a laboratory-based Rowland-circle monochromator that incorporates a low power x-ray (bremsstrahlung) tube source, a spherically bent crystal analyzer, and an energy-resolving solid-state detector. This relatively inexpensive, introductory level instrument achieves 1-eV energy resolution for photon energies of ?5 keV to ?10 keV while also demonstrating a net efficiency previously seen only in laboratory monochromators having much coarser energy resolution. Despite the use of only a compact, air-cooled 10 W x-ray tube, we find count rates for nonresonant x-ray emission spectroscopy comparable to those achieved at monochromatized spectroscopy beamlines at synchrotron light sources. For x-ray absorption near edge structure, the monochromatized flux is small (due to the use of a low-powered x-ray generator) but still useful for routine transmission-mode studies of concentrated samples. These results indicate that upgrading to a standard commercial high-power line-focused x-ray tube or rotating anode x-ray generator would result in monochromatized fluxes of order 10{sup 6}–10{sup 7} photons/s with no loss in energy resolution. This work establishes core technical capabilities for a rejuvenation of laboratory-based hard x-ray spectroscopies that could have special relevance for contemporary research on catalytic or electrical energy storage systems using transition-metal, lanthanide, or noble-metal active species.

  2. Continuous fine ash depressurization system

    DOE Patents [OSTI]

    Liu, Guohai (Birmingham, AL); Peng, Wan Wang (Birmingham, AL); Vimalchand, Pannalal (Birmingham, AL)

    2011-11-29

    A system for depressurizing and cooling a high pressure, high temperature fine solid particles stream having entrained gas therein. In one aspect, the system has an apparatus for cooling the high pressure, high temperature fine solid particles stream having entrained gas therein and a pressure letdown device for depressurization by separating the cooled fine solid particles from a portion of the fine solid particles stream having entrained gas therein, resulting in a lower temperature, lower pressure outlet of solid particles for disposal or handling by downstream equipment.

  3. Structural and dynamical properties of Bridgman-grown CdSe[subscript x]Te[subscript 1?x] (0

    E-Print Network [OSTI]

    Talwar, Devki N.

    Measurements of the Raman scattering and extended x-ray-absorption fine-structure (EXAFS) spectroscopy are reported on a series of Bridgman-grown zinc-blende CdTe[subscript 1?x]Se[subscript x] (0.35 ? x > 0.05) ternary ...

  4. Microlensing induced absorption line variability

    E-Print Network [OSTI]

    Geraint F. Lewis; Rodrigo A. Ibata

    2002-12-02

    Gravitational microlensing has proven to be a powerful probe of both the structure at the heart of quasars and the mass function of compact objects in foreground lenses. This paper examines the potential of gravitational microlensing in probing the scale of structure in absorbing material within the lensing galaxy. We find that, in this high optical depth regime, significant variations in the equivalent width of absorption features can be induced, although the details of these are dependent upon the scale of structure of the absorbing material. The paper concludes with an examination of the absorption line variability observed in the gravitationally lensed quasar PKS1830-211, demonstrating how this may indicate the presence of small scale structure in the cold molecular gas present within the lensing galaxy.

  5. Interpretation of Wild 2 Dust Fine Structure: Comparison of Stardust Aluminium Foil Craters to the Three-Dimensional Shape of Experimental Impacts by Artificial Aggregate Particles and Meteorite Powders

    SciTech Connect (OSTI)

    Kearsley, A T; Burchell, M J; Price, M C; Graham, G A; Wozniakiewicz, P J; Cole, M J; Foster, N J; Teslich, N

    2009-12-10

    New experimental results show that Stardust crater morphology is consistent with interpretation of many larger Wild 2 dust grains being aggregates, albeit most of low porosity and therefore relatively high density. The majority of large Stardust grains (i.e. those carrying most of the cometary dust mass) probably had density of 2.4 g cm{sup -3} (similar to soda-lime glass used in earlier calibration experiments) or greater, and porosity of 25% or less, akin to consolidated carbonaceous chondrite meteorites, and much lower than the 80% suggested for fractal dust aggregates. Although better size calibration is required for interpretation of the very smallest impacting grains, we suggest that aggregates could have dense components dominated by {micro}m-scale and smaller sub-grains. If porosity of the Wild 2 nucleus is high, with similar bulk density to other comets, much of the pore-space may be at a scale of tens of micrometers, between coarser, denser grains. Successful demonstration of aggregate projectile impacts in the laboratory now opens the possibility of experiments to further constrain the conditions for creation of bulbous (Type C) tracks in aerogel, which we have observed in recent shots. We are also using mixed mineral aggregates to document differential survival of pristine composition and crystalline structure in diverse fine-grained components of aggregate cometary dust analogues, impacted onto both foil and aerogel under Stardust encounter conditions.

  6. Hot Gas Filtration of Fine and Ultra fine Particles with Liquid...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hot Gas Filtration of Fine and Ultra fine Particles with Liquid Phase Sintered SiC Ceramic DPF Hot Gas Filtration of Fine and Ultra fine Particles with Liquid Phase Sintered SiC...

  7. Trends in the Carbonyl Core (C 1S, O 1S) f *C)O Transition in the Near-Edge X-ray Absorption Fine Structure Spectra of Organic Molecules

    E-Print Network [OSTI]

    ,2 meteorites3 and interplanetary dust particles,4 eocene and recent wood,5,6 coal, coke, and other organic

  8. Fine Structure Studies in Proton Emission

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverse (Journal Article) |Final Reportthe Growing American Auto

  9. X-ray-absorption study of CuBr at high pressure

    SciTech Connect (OSTI)

    Tranquada, J.M.; Ingalls, R.

    1986-09-15

    The x-ray-absorption spectrum of cuprous bromide has been measured as a function of pressure. The x-ray-absorption near-edge structure proved to be an excellent indicator of high-pressure phase transitions in this material. The normalized ''white-line'' peak heights at both the Cu and Br K-italic edges decreased on entering the tetragonal phase and increased in going to the NaCl structure. The zinc-blende to tetragonal phase transition took place over a very narrow pressure range centered at 46 +- 5 kbar. The transformation from the tetragonal to the NaCl structure, on the other hand, showed a broad mixed-phase region, suggesting a nucleation-and-growth mechanism for the transition. The mixed-phase region was centered at 75 +- 6 kbar. No evidence of a phase between the zinc-blende and tetragonal phases was observed, presumably because it does not exist. Analysis of the extended x-ray-absorption fine-structure (EXAFS) clearly showed that there is no change in coordination in going from the zinc-blende to the tetragonal phase although the nearest-neighbor distance increases slightly. A much larger increase in R-italic/sub 1/ occurs at the transition to the NaCl structure, where the coordination increases from 4 to 6. The mean-square deviation in the nearest-neighbor bond length, sigma/sub 1//sup 2/, appears to be a fairly smooth function of nearest-neighbor distance, decreasing (or increasing) as R-italic/sub 1/ decreases (or increases) more or less independent of structure. Evidence from the literature was presented to suggest that the zinc-blende to tetragonal transition in CuBr (and also CuCl) should occur by shear deformation.

  10. Enhanced light absorption of solar cells and photodetectors by diffraction

    DOE Patents [OSTI]

    Zaidi, Saleem H.; Gee, James M.

    2005-02-22

    Enhanced light absorption of solar cells and photodetectors by diffraction is described. Triangular, rectangular, and blazed subwavelength periodic structures are shown to improve performance of solar cells. Surface reflection can be tailored for either broadband, or narrow-band spectral absorption. Enhanced absorption is achieved by efficient optical coupling into obliquely propagating transmitted diffraction orders. Subwavelength one-dimensional structures are designed for polarization-dependent, wavelength-selective absorption in solar cells and photodetectors, while two-dimensional structures are designed for polarization-independent, wavelength-selective absorption therein. Suitable one and two-dimensional subwavelength periodic structures can also be designed for broadband spectral absorption in solar cells and photodetectors. If reactive ion etching (RIE) processes are used to form the grating, RIE-induced surface damage in subwavelength structures can be repaired by forming junctions using ion implantation methods. RIE-induced surface damage can also be removed by post RIE wet-chemical etching treatments.

  11. Residential Absorption Water Heater

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Residential Absorption Water Heater 2014 Building Technologies Office Peer Review Kyle Gluesenkamp, gluesenkampk@ornl.gov Oak Ridge National Laboratory Project Summary Timeline:...

  12. Structure of Palladium Nanoclusters for Hydrogen Gas Sensors

    SciTech Connect (OSTI)

    Stevens, K.J.; Ingham, B.; Toney, M.F.; Brown, S.A.; Lassesson, A.; /SLAC, SSRL /Canterbury U.

    2009-05-11

    Palladium nanoclusters produced by inert gas aggregation/magnetron sputtering are used as building blocks for the construction of nano electronic devices with large surface to volume ratios that can be used as sensitive hydrogen gas sensors in fuel cells and in petrochemical plants. X-ray diffraction (XRD), extended X-ray absorption fine structure (EXAFS), and high resolution transmission electron microscopy (HRTEM) have been used to characterize the structure, lattice constant, particle diameter and oxide thickness of the palladium nanoclusters in order to understand the operation of these sensors. Grazing incidence XRD (GIXRD) of heat treated Pd clusters has shown that the palladanite structure forms at elevated temperatures.

  13. X-ray absorption spectroscopic studies of the active sites of nickel- and copper-containing metalloproteins

    SciTech Connect (OSTI)

    Tan, G.O.

    1993-06-01

    X-ray absorption spectroscopy (XAS) is a useful tool for obtaining structural and chemical information about the active sites of metalloproteins and metalloenzymes. Information may be obtained from both the edge region and the extended X-ray absorption fine structure (EXAFS) or post-edge region of the K-edge X-ray absorption spectrum of a metal center in a compound. The edge contains information about the valence electronic structure of the atom that absorbs the X-rays. It is possible in some systems to infer the redox state of the metal atom in question, as well as the geometry and nature of ligands connected to it, from the features in the edge in a straightforward manner. The EXAFS modulations, being produced by the backscattering of the ejected photoelectron from the atoms surrounding the metal atom, provide, when analyzed, information about the number and type of neighbouring atoms, and the distances at which they occur. In this thesis, analysis of both the edge and EXAFS regions has been used to gain information about the active sites of various metalloproteins. The metalloproteins studied were plastocyanin (Pc), laccase and nickel carbon monoxide dehydrogenase (Ni CODH). Studies of Cu(I)-imidazole compounds, related to the protein hemocyanin, are also reported here.

  14. Solar absorption surface panel

    DOE Patents [OSTI]

    Santala, Teuvo J. (Attleboro, MA)

    1978-01-01

    A composite metal of aluminum and nickel is used to form an economical solar absorption surface for a collector plate wherein an intermetallic compound of the aluminum and nickel provides a surface morphology with high absorptance and relatively low infrared emittance along with good durability.

  15. Laminar: Practical Fine-Grained Decentralized Information Flow Control

    E-Print Network [OSTI]

    Witchel, Emmett

    Laminar: Practical Fine-Grained Decentralized Information Flow Control Indrajit Roy Donald E-grained program data structures. This paper describes Laminar, the first system to implement de- centralized the labeled data in lexically scoped secu- rity regions. Laminar enforces the security policies specified

  16. Compressive behavior of fine sand.

    SciTech Connect (OSTI)

    Martin, Bradley E.; Kabir, Md. E.; Song, Bo; Chen, Wayne

    2010-04-01

    The compressive mechanical response of fine sand is experimentally investigated. The strain rate, initial density, stress state, and moisture level are systematically varied. A Kolsky bar was modified to obtain uniaxial and triaxial compressive response at high strain rates. A controlled loading pulse allows the specimen to acquire stress equilibrium and constant strain-rates. The results show that the compressive response of the fine sand is not sensitive to strain rate under the loading conditions in this study, but significantly dependent on the moisture content, initial density and lateral confinement. Partially saturated sand is more compliant than dry sand. Similar trends were reported in the quasi-static regime for experiments conducted at comparable specimen conditions. The sand becomes stiffer as initial density and/or confinement pressure increases. The sand particle size become smaller after hydrostatic pressure and further smaller after dynamic axial loading.

  17. Dense, finely, grained composite materials

    DOE Patents [OSTI]

    Dunmead, Stephen D. (Davis, CA); Holt, Joseph B. (San Jose, CA); Kingman, Donald D. (Danville, CA); Munir, Zuhair A. (Davis, CA)

    1990-01-01

    Dense, finely grained composite materials comprising one or more ceramic phase or phase and one or more metallic and/or intermetallic phase or phases are produced by combustion synthesis. Spherical ceramic grains are homogeneously dispersed within the matrix. Methods are provided, which include the step of applying mechanical pressure during or immediately after ignition, by which the microstructures in the resulting composites can be controllably selected.

  18. Resonant Absorption of Transverse Oscillations and Associated Heating in a Solar Prominence. I- Observational aspects

    E-Print Network [OSTI]

    Okamoto, Takenori J; De Pontieu, Bart; Uitenbroek, Han; Van Doorsselaere, Tom; Yokoyama, Takaaki

    2015-01-01

    Transverse magnetohydrodynamic (MHD) waves have been shown to be ubiquitous in the solar atmosphere and can in principle carry sufficient energy to generate and maintain the Sun's million-degree outer atmosphere or corona. However, direct evidence of the dissipation process of these waves and subsequent heating has not yet been directly observed. Here we report on high spatial, temporal, and spectral resolution observations of a solar prominence that show a compelling signature of so-called resonant absorption, a long hypothesized mechanism to efficiently convert and dissipate transverse wave energy into heat. Aside from coherence in the transverse direction, our observations show telltale phase differences around 180 degrees between transverse motions in the plane-of-sky and line-of-sight velocities of the oscillating fine structures or threads, and also suggest significant heating from chromospheric to higher temperatures. Comparison with advanced numerical simulations support a scenario in which transverse...

  19. Use of Wood Waste in Rehabilitation of Landings Constructed on Fine-Textured

    E-Print Network [OSTI]

    Sanborn, Paul

    Use of Wood Waste in Rehabilitation of Landings Constructed on Fine-Textured Soils, Central landings and roads constructed on fine-textured Alfisols must ameliorate poor soil structure, high bulk rehabilitated with three operationally feasible treatments: (1) incorpora- tion of waste wood chips (140 t

  20. Formaldehyde Absorption toward W51

    E-Print Network [OSTI]

    Kogut, A.; Smoot, G.F.; Bennett, C.L.; Petuchowski, S.J.

    1988-01-01

    to Astrophysical Journal Formaldehyde Absorption toward W51Number DE-AC03-76SF00098. FORMALDEHYDE ABSORPTION TOWARD W51We have measured formaldehyde (H2CO) absorption toward the

  1. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  2. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon (Oak Ridge, TN)

    1984-01-01

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  3. Combined in Situ X-ray absorption and diffuse reflectance infraredspectroscopy: An attractive tool for catalytic investigations

    SciTech Connect (OSTI)

    Marinkovic, N.S.; Ehrlich, S.; Wang, Q.; Barrio, L.; Khalid, S.; et.al.

    2010-11-24

    Catalysis investigations are often followed in a range of spectroscopic techniques. While diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) can be done on a bench-top instrument, X-ray absorption spectroscopy (XAS) techniques, such as extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) require synchrotron light. In order to ensure the same conditions during in situ catalysis for each method, a combined XAS/DRIFTS has been developed at beamline X18A at the National Synchrotron Light Source, Brookhaven National Laboratory. A rapid-scan FTIR spectrometer capable of both mid- and far-infrared measurements is equipped with an arm to redirect the IR beam outside the spectrometer. An in situ reaction chamber, equipped with glassy carbon windows for X-ray light and a KBr window for IR light passage is installed firmly on the arm. The reaction cell can be heated to 600 C and allows passage of gases through the catalyst so that both XAS and DRIFTS techniques can be done simultaneously in controlled environment conditions. Together with a fast-moving monochromator for quick-EXAFS and mass-spectrometric residual gas analysis, this new tool is a powerful method for testing catalytic reactions in real time.

  4. Seven-effect absorption refrigeration

    DOE Patents [OSTI]

    DeVault, R.C.; Biermann, W.J.

    1989-05-09

    A seven-effect absorption refrigeration cycle is disclosed utilizing three absorption circuits. In addition, a heat exchanger is used for heating the generator of the low absorption circuit with heat rejected from the condenser and absorber of the medium absorption circuit. A heat exchanger is also provided for heating the generator of the medium absorption circuit with heat rejected from the condenser and absorber of the high absorption circuit. If desired, another heat exchanger can also be provided for heating the evaporator of the high absorption circuit with rejected heat from either the condenser or absorber of the low absorption circuit. 1 fig.

  5. Picobubble enhanced fine coal flotation

    SciTech Connect (OSTI)

    Tao, Y.J.; Liu, J.T.; Yu, S.; Tao, D. [University of Kentucky, Lexington, KY (United States). Dept. of Mining Engineering

    2006-07-01

    Froth flotation is widely used in the coal industry to clean -28 mesh fine coal. A successful recovery of particles by flotation depends on efficient particle-bubble collision and attachment with minimal subsequent particle detachment from bubble. Flotation is effective in a narrow size range beyond which the flotation efficiency drops drastically. It is now known that the low flotation recovery of particles in the finest size fractions is mainly due to a low probability of bubble-particle collision while the main reason for poor coarse particle flotation recovery is the high probability of detachment. A fundamental analysis has shown that use of picobubbles can significantly improve the flotation recovery of particles in a wide range of size by increasing the probability of collision and attachment and reducing the probability of detachment. A specially designed column with a picobubble generator has been developed for enhanced recovery of fine coal particles. Picobubbles were produced based on the hydrodynamic cavitation principle. They are characterized by a size distribution that is mostly below 1 {mu}m and adhere preferentially to the hydrophobic surfaces. The presence of picobubbles increases the probability of collision and attachment and decreases the probability of detachment, thus enhancing flotation recovery. Experimental results with the Coalberg seam coal in West Virginia, U.S.A. have shown that the use of picobubbles in a 2 in. column flotation increased fine coal recovery by 10-30%, depending on the feed rate, collector dosage, and other flotation conditions. Picobubbles also acted as a secondary collector and reduced the collector dosage by one third to one half.

  6. Suppression of thermal carrier escape and efficient photo-carrier generation by two-step photon absorption in InAs quantum dot intermediate-band solar cells using a dot-in-well structure

    SciTech Connect (OSTI)

    Asahi, S.; Teranishi, H.; Kasamatsu, N.; Kada, T.; Kaizu, T.; Kita, T.

    2014-08-14

    We investigated the effects of an increase in the barrier height on the enhancement of the efficiency of two-step photo-excitation in InAs quantum dot (QD) solar cells with a dot-in-well structure. Thermal carrier escape of electrons pumped in QD states was drastically reduced by sandwiching InAs/GaAs QDs with a high potential barrier of Al{sub 0.3}Ga{sub 0.7}As. The thermal activation energy increased with the introduction of the barrier. The high potential barrier caused suppression of thermal carrier escape and helped realize a high electron density in the QD states. We observed efficient two-step photon absorption as a result of the high occupancy of the QD states at room temperature.

  7. Advanced composites are being widely used in aerospace applications due to their high stiffness, strength and energy absorption capabilities. However, the assurance of structural

    E-Print Network [OSTI]

    is placed on modeling the nonlinearity and failure of both polymer matrix and ceramic matrix compositesAdvanced composites are being widely used in aerospace applications due to their high stiffness issue because a damage event will compromise the integrity of composite structures and lead to ultimate

  8. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon (Oak Ridge, TN); Perez-Blanco, Horacio (Knoxville, TN)

    1984-01-01

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  9. The Access Almanac: Graduated Parking Fines

    E-Print Network [OSTI]

    Shoup, Donald

    2010-01-01

    THE ACCESS ALMANAC Graduated Parking Fines BY DONALD SHOUPC ITIES OFTEN INCREASE THEIR PARKING FINESWHEN overtime parking in a calendar year is $35, the second

  10. Physical features of small disperse coal dust fraction transportation and structurization processes in iodine air filters of absorption type in ventilation systems at nuclear power plants

    E-Print Network [OSTI]

    Ledenyov, Oleg P; Poltinin, P Ya; Fedorova, L I

    2012-01-01

    The research on the physical features of transportation and structurization processes by the air-dust aerosol in the granular filtering medium with the cylindrical coal adsorbent granules in an air filter of the adsorption type in the heating ventilation and cooling (HVAC) system at the nuclear power plant is completed. The physical origins of the coal dust masses distribution along the absorber with the granular filtering medium with the cylindrical coal granules during the air-dust aerosol intake process in the near the surface layer of absorber are researched. The quantitative technical characteristics of air filtering elements, which have to be considered during the optimization of air filters designs for the application in the ventilation systems at the nuclear power plants, are obtained.

  11. Roadmap: Fine Arts Interdisciplinary Painting/Sculpture Bachelor of Fine Arts

    E-Print Network [OSTI]

    Sheridan, Scott

    Roadmap: Fine Arts ­ Interdisciplinary Painting/Sculpture ­ Bachelor of Fine Arts [CA This roadmap is a recommended semester-by-semester plan of study for this major. However, courses on page 2 Kent Core Requirement 3 #12;Roadmap: Fine Arts ­ Interdisciplinary Painting/Sculpture ­ Bachelor

  12. Roadmap: Fine Arts Interdisciplinary Drawing/Sculpture Bachelor of Fine Arts

    E-Print Network [OSTI]

    Sheridan, Scott

    Roadmap: Fine Arts ­ Interdisciplinary Drawing/Sculpture ­ Bachelor of Fine Arts [CA This roadmap is a recommended semester-by-semester plan of study for this major. However, courses on page 2 Kent Core Requirement 3 #12;Roadmap: Fine Arts ­ Interdisciplinary Drawing/Sculpture ­ Bachelor

  13. ORIGINAL ARTICLE Fine Particulate Matter and Mortality

    E-Print Network [OSTI]

    Dominici, Francesca

    ORIGINAL ARTICLE Fine Particulate Matter and Mortality A Comparison of the Six Cities and AmericanDermott,* and Francesca Dominici* Background: The American Cancer Society study and the Harvard Six Cities study are 2 landmark cohort studies for estimating the chronic effects of fine particulate air pollution (PM2

  14. Oral Drug Absorption

    E-Print Network [OSTI]

    Yamashita, Shinji

    2006-10-26

    Stability 0 20 40 60 80 100 25 10 5 1 0.5 size? r 0 (?m) Fr action absor b ed in hum an (% ) Peff =5.0 Peff =3.0 Peff =1.0 Peff =0.5 Peff =0.1 Solubility? Cs = 1.0 (?g/ml) Effect of micronization on intestinal absorption of poorly soluble drugs Peff... ?? permeability to human intestine? (cm/sec x 10 -4 ) 8 Effect of Solubility on intestinal absorption of poorly soluble drugs Cs (?g/ml) 0 5 10 15 50 Fr action absor b ed in hum an (% ) 0 20 40 60 80 100 Peff =5.0 Peff =3.0 Peff =1.0 Peff =0.5 Peff =0.1 r 0 = 1...

  15. Plasmon absorption modulator systems and methods

    DOE Patents [OSTI]

    Kekatpure, Rohan Deodatta; Davids, Paul

    2014-07-15

    Plasmon absorption modulator systems and methods are disclosed. A plasmon absorption modulator system includes a semiconductor substrate, a plurality of quantum well layers stacked on a top surface of the semiconductor substrate, and a metal layer formed on a top surface of the stack of quantum well layers. A method for modulating plasmonic current includes enabling propagation of the plasmonic current along a metal layer, and applying a voltage across the stack of quantum well layers to cause absorption of a portion of energy of the plasmonic current by the stack of quantum well layers. A metamaterial switching system includes a semiconductor substrate, a plurality of quantum well layers stacked on a top surface of the semiconductor substrate, and at least one metamaterial structure formed on a top surface of the stack of quantum well layers.

  16. Absorption in dielectric models

    E-Print Network [OSTI]

    Churchill, R J

    2015-01-01

    We develop a classical microscopic model of a dielectric. The model features nonlinear interaction terms between polarizable dipoles and lattice vibrations. The lattice vibrations are found to act as a pseudo-reservoir, giving broadband absorption of electromagnetic radiation without the addition of damping terms in the dynamics. The effective permittivity is calculated using a perturbative iteration method and is found to have the form associated with real dielectrics. Spatial dispersion is naturally included in the model and we also calculate the wavevector dependence of the permittivity.

  17. Swift heavy ion irradiation of Pt nanocrystals: II. Structural changes and H desorption

    SciTech Connect (OSTI)

    Giulian, R.; Araujo, L.L.; Kluth, P.; Sprouster, D.J.; Schnohr, C.S.; Byrne, A.P.; Ridgway, M.C. (ANU)

    2014-09-24

    The structural properties and H desorption from embedded Pt nanocrystals (NCs) following irradiation with swift heavy ions were investigated as a function of energy and fluence. From x-ray absorption near-edge spectroscopy analysis, Pt-H bonding was identified in NCs annealed in a forming gas (95% N{sub 2} + 5% H{sub 2}) ambient. The H content decreased upon irradiation and the desorption process was NC-size dependent such that larger NCs required a higher fluence to achieve a H-free state. Pt-H bonding and NC dissolution both perturbed the NC structural parameters (coordination number, bond-length and mean-square relative displacement) as determined with extended x-ray absorption fine structure measurements.

  18. Name: _______________________________ MASTER OF FINE ARTS: MUSIC

    E-Print Network [OSTI]

    Al Faruque, Mohammad Abdullah

    Name: _______________________________ MASTER OF FINE ARTS: MUSIC INSTRUMENTAL PERFORMANCE Degree Requirements (2014-2015) Music 131 (Post-Tonal Theory) ______ 4 units Music 160, or 161 (Large Ensemble of 12 units of Music 160, 161. ______ ______ ______ ______ ______ ______ Music 176 (Chamber Ensembles

  19. Immobilization of Rocky Flats Graphite Fines Residue

    SciTech Connect (OSTI)

    Rudisill, T.S.

    1999-04-06

    The development of the immobilization process for graphite fines has proceeded through a series of experimental programs. The experimental procedures and results from each series of experiments are discussed in this report.

  20. Absorption and transport properties of ultra-fine cellulose webs Gerardo Callegari a,

    E-Print Network [OSTI]

    Muzzio, Fernando J.

    Electrospinning Cellulose Nanoweb Kozeny­Carman Washburn a b s t r a c t Characterization of transport or particles. In electrospinning (ES), a polymer solution or melt droplet formed at the opening of a thin

  1. Segmentation and Enhancement of Latent Fingerprints: A Coarse to Fine Ridge

    E-Print Network [OSTI]

    ., "Image Quality Assessment: From Error Visibility to Structural Similarity", IEEE Transaction on ImageSegmentation and Enhancement of Latent Fingerprints: A Coarse to Fine Ridge Structure Dictionary ridge Pores · Include all dimensional attributes of the ridge such as pores, edge contour, incipient

  2. Development of an Advanced Fine Coal Suspension Dewatering Process

    SciTech Connect (OSTI)

    B. K. Parekh; D. P. Patil

    2008-04-30

    With the advancement in fine coal cleaning technology, recovery of fine coal (minus 28 mesh) has become an attractive route for the U.S. coal industry. The clean coal recovered using the advanced flotation technology i.e. column flotation, contains on average 20% solids and 80% water, with an average particle size of 35 microns. Fine coal slurry is usually dewatered using a vacuum dewatering technique, providing a material with about 25 to 30 percent moisture. The process developed in this project will improve dewatering of fine (0.6mm) coal slurry to less than 20 percent moisture. Thus, thermal drying of dewatered wet coal will be eliminated. This will provide significant energy savings for the coal industry along with some environmental benefits. A 1% increase in recovery of coal and producing a filter cake material of less than 20 % moisture will amount to energy savings of 1900 trillion Btu/yr/unit. In terms of the amount of coal it will be about 0.8% of the total coal being used in the USA for electric power generation. It is difficult to dewater the fine clean coal slurry to about 20% moisture level using the conventional dewatering techniques. The finer the particle, the larger the surface area and thus, it retains large amounts of moisture on the surface. The coal industry has shown some reluctance in using the advanced coal recovery techniques, because of unavailability of an economical dewatering technique which can provide a product containing less than 20% moisture. The U.S.DOE and Industry has identified the dewatering of coal fines as a high priority problem. The goal of the proposed program is to develop and evaluate a novel two stage dewatering process developed at the University of Kentucky, which involves utilization of two forces, namely, vacuum and pressure for dewatering of fine coal slurries. It has been observed that a fine coal filter cake formed under vacuum has a porous structure with water trapped in the capillaries. When this porous cake is subjected to pressure for a short time, the free water present is released from the filter cake. Laboratory studies have shown that depending on the coal type a filter cake containing about 15% moisture could be obtained using the two-stage filtration technique. It was also noted that applying intermittent breaks in vacuum force during cake formation, which disturbed the cake structure, helped in removing moisture from the filter cakes. In this project a novel approach of cleaning coal using column flotation was also developed. With this approach the feed capacity of the column is increased significantly, and the column was also able to recover coarser size coal which usually gets lost in the process. The outcome of the research benefits the coal industry, utility industry, and indirectly the general public. The benefits can be counted in terms of clean energy, cleaner environment, and lower cost power.

  3. Americium characterization by X-ray fluorescence and absorption spectroscopy in plutonium uranium mixed oxide

    SciTech Connect (OSTI)

    Degueldre, Claude Cozzo, Cedric; Martin, Matthias; Grolimund, Daniel; Mieszczynski, Cyprian

    2013-06-01

    Plutonium uranium mixed oxide (MOX) fuels are currently used in nuclear reactors. The actinides in these fuels need to be analyzed after irradiation for assessing their behaviour with regard to their environment and the coolant. In this work the study of the atomic structure and next-neighbour environment of Am in the (Pu,U)O? lattice in an irradiated (60 MW d kg?¹) MOX sample was performed employing micro-X-ray fluorescence (µ-XRF) and micro-X-ray absorption fine structure (µ-XAFS) spectroscopy. The chemical bonds, valences and stoichiometry of Am (~0.66 wt%) are determined from the experimental data gained for the irradiated fuel material examined in its peripheral zone (rim) of the fuel. In the irradiated sample Am builds up as Am³? species within an [AmO?]¹³? coordination environment (e.g. >90%) and no (<10%) Am(IV) or (V) can be detected in the rim zone. The occurrence of americium dioxide is avoided by the redox buffering activity of the uranium dioxide matrix. - Graphical abstract: Americium LIII XAFS spectra recorded for the irradiated MOX sub-sample in the rim zone for a 300 ?m×300 ?m beam size area investigated over six scans of 4 h. The records remain constant during multi-scan. The analysis of the XAFS signal shows that Am is found as trivalent in the UO? matrix. This analytical work shall open the door of very challenging analysis (speciation of fission product and actinides) in irradiated nuclear fuels. - Highlights: • Americium was characterized by microX-ray absorption spectroscopy in irradiated MOX fuel. • The americium redox state as determined from XAS data of irradiated fuel material was Am(III). • In the sample, the Am³? face an AmO?¹³?coordination environment in the (Pu,U)O? matrix. • The americium dioxide is reduced by the uranium dioxide matrix.

  4. 1 Fine Arts and Art History FINE ARTS AND ART HISTORY

    E-Print Network [OSTI]

    Vertes, Akos

    1 Fine Arts and Art History FINE ARTS AND ART HISTORY Through the making of art and the study of its history, students develop a visual literacy and skills in critical thinking. The undergraduate grounded in related historical and theoretical issues. In the art history curriculum, students gain an in

  5. Absorption-induced transparency metamaterials in the terahertz regime

    E-Print Network [OSTI]

    Rodrigo, Sergio G

    2015-01-01

    Contrary to what might be expected, when an organic dye is sputtered onto an opaque holey metal film, transmission bands can be observed at the absorption energies of the molecules. This phenomenon, known as absorption-induced transparency, is aided by a strong modification of the propagation properties of light inside the holes when filled by the molecules. Despite having been initially observed in metallic structures in the optical regime, new routes for investigation and applications at different spectral regimes can be devised. Here, in order to illustrate the potential use of absorption induced transparency at terahertz, a method for molecular detection is presented, supported by a theoretical analysis.

  6. Deciphering Ni sequestration in soil ferromanganese nodules by combining x-ray fluorescence, absorption and diffraction at micrometer scales of resolution

    SciTech Connect (OSTI)

    Manceau, Alain; Tamura, Nobumichi; Marcus, Matthew A.; MacDowell, Alastair A.; Celestre, Richard S.; Sublett, Robert E.; Sposito, Garrison; Padmore, Howard A.

    2002-11-06

    X-ray microprobes are among the most important new analytical techniques to emerge from third generation synchrotron facilities. Here we show how X-ray fluorescence, diffraction, and absorption can be used in parallel to determine the structural form of trace elements in heterogeneous matrices at the micrometer-scale of resolution. Scanning X-ray microfluorescence (microSXRF) and microdiffraction (microSXRD) first are used to identify the host solid phase by mapping the distributions of elements and solid species, respectively. Micro-extended X-ray absorption fine structure (microEXAFS) spectroscopy is then used to determine the mechanism of trace element binding by the host phase at the molecular scale. To illustrate the complementary application of these three techniques, we studied how nickel is sequestered in soil ferromanganese nodules, an overwhelmingly complex natural matrix consisting of submicrometer to nanometer sized particles with varying structures and chemical composition s. We show that nickel substitutes for Mn3+ in the manganese layer of the MnO2-Al(OH)3 mixed-layer oxide lithiophorite. The affinity of Ni for lithiophorite was characteristic of micromodules sampled from soils across the U.S.A. and Europe. Since many natural and synthetic materials are heterogeneous at nanometer to micrometer scales, the synergistic use of microSXRF, microSXRD and microEXAFS is expected to have broad applications to earth and materials science.

  7. Use of micro-XANES to speciate chromium in airborne fine particles in the Sacramento Valley

    SciTech Connect (OSTI)

    Michelle L. Werner; Peter S. Nico; Matthew A. Marcus; Cort Anastasio

    2007-07-15

    While particulate matter (PM) in the atmosphere can lead to a wide array of negative health effects, the cause of toxicity is largely unknown. One aspect of PM that likely affects health is the chemical composition, in particular the transition metals within the particles. Chromium is one transition metal of interest due to its two major oxidation states, with Cr(III) being much less toxic compared to Cr(VI). Using microfocused X-ray absorption near edge structure (micro-XANES), we analyzed the Cr speciation in fine particles (diameters {le} 2.5 {mu}m) collected at three sites in the Sacramento Valley of northern California: Sacramento, a large urban area, Davis, a small city, and Placerville, a rural area. These are several major stationary sources of Cr within 24 km of the site including chrome-plating plants, power plants and incinerators. The microfocused X-ray beam enables us to look at very small areas on the filter with a resolution of typically 5-7 micrometers. With XANES we are able to not only distinguish between Cr(VI) and Cr(III), but also to identify different types of Cr(III) and more reduced Cr species. At all of our sampling sites the main Cr species were Cr(III), with Cr(OH){sub 3} or a Cr-Fe, chromite-like, phase being the dominant species. Cr(VI)-containing particles were found only in the most urban site. All three sites contained some reduced Cr species, either Cr(0) or Cr{sub 3}C{sub 2}, although these were minor components. This work demonstrates that micro-XANES can be used as a minimally invasive analytical tool to investigate the composition of ambient PM. 32 refs., 6 figs.

  8. Optical absorption of silicon nanowires

    SciTech Connect (OSTI)

    Xu, T. [Key Laboratory of Advanced Display and System Application, Shanghai University, 149 Yanchang Road, Shanghai 200072 (China); Institut d'Electronique et de Microelectronique et de Nanotechnologies, IEMN (CNRS, UMR 8520), Groupe de Physique, Cite scientifique, avenue Poincare, 59652 Villeneuve d'Ascq (France); Lambert, Y.; Krzeminski, C.; Grandidier, B.; Stievenard, D.; Leveque, G.; Akjouj, A.; Pennec, Y.; Djafari-Rouhani, B. [Institut d'Electronique et de Microelectronique et de Nanotechnologies, IEMN (CNRS, UMR 8520), Groupe de Physique, Cite scientifique, avenue Poincare, 59652 Villeneuve d'Ascq (France)

    2012-08-01

    We report on simulations and measurements of the optical absorption of silicon nanowires (NWs) versus their diameter. We first address the simulation of the optical absorption based on two different theoretical methods: the first one, based on the Green function formalism, is useful to calculate the scattering and absorption properties of a single or a finite set of NWs. The second one, based on the finite difference time domain (FDTD) method, is well-adapted to deal with a periodic set of NWs. In both cases, an increase of the onset energy for the absorption is found with increasing diameter. Such effect is experimentally illustrated, when photoconductivity measurements are performed on single tapered Si nanowires connected between a set of several electrodes. An increase of the nanowire diameter reveals a spectral shift of the photocurrent intensity peak towards lower photon energies that allow to tune the absorption onset from the ultraviolet radiations to the visible light spectrum.

  9. Simulations of solar cell absorption enhancement using resonant modes

    E-Print Network [OSTI]

    Grandidier, Jonathan

    for enhancing the absorption of thin-film amorphous silicon solar cells using periodic arrangements of resonant,7 Dielectric nanospheres are promising structures for light trapping in planar, thin-film solar cells. It has a thin-film a-Si solar cell structure featuring back reflector and optimized anti-reflection coating. We

  10. LAMINAR: PRACTICAL FINE-GRAINED DECENTRALIZED INFORMATION

    E-Print Network [OSTI]

    Witchel, Emmett

    LAMINAR: PRACTICAL FINE-GRAINED DECENTRALIZED INFORMATION FLOW CONTROL (DIFC) Indrajit Roy, Donald} {} Information flow in a lattice #12;In this talk: Laminar A practical way to provide end-to-end security guarantees. #12;Outline Comparison with current DIFC systems Laminar: programming model Design: PL + OS

  11. Art Practices Bachelor of Fine Arts

    E-Print Network [OSTI]

    Elzanowski, Marek

    Art Practices Bachelor of Fine Arts 201516 Degree Map First Year Fall Winter Spring courses (by end of spring term). Freshman Inquiry 5 Freshman Inquiry 5 Freshman Inquiry 5 ART 115 4 ART 117 4 ART 182 4 ART 131 4 ART 119 4 ART 204 or 205 4 Foreign Language 101 4

  12. The high conversion LC-Fining process

    SciTech Connect (OSTI)

    VanDriesen, R.P.; Strangio, V.A.; Rhoe, A.; Kolstad, J.J.

    1986-01-01

    Residual oil hydrocracking has been practiced at moderate conversions for many years on a wide range of feedstocks. Processes utilizing expanded bed reactors have been proven to be effective in the hydrocracking of these heavy residual feedstocks. Conversions up to 60% vacuum bottoms to distillates were routinely obtained in several commercial units. More recently Amoco has been operating an LC-Fining unit in their Texas City refinery at conversions as high as 80%. Normal conversion in this plant however is 60-65%. LC-Fining is an expanded bed resid hydrocracking and hydrodesulfurization process developed by Cities Service and Lummus Crest. There are a number of factors which may limit the conversion in any given plant site. These include compatibility problems with the liquid product, settling out of heavy hydrocarbons in downstream equipment or fouling of the catalyst in the reactor which in the extreme results in coking of the catalyst bed. The operator of a residual hydrocracker maintains conversion at a sufficiently low level to avoid these problems. Recent advances in the LC-Fining technology have led to the development of the High Conversion LC-Fining Process which is capable of operation at conversions of 95% and higher without any of these problems.

  13. 700:20131001.1211 Fine Sun Sensor

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    700:20131001.1211 Fine Sun Sensor The Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado, Boulder is a world leader in space-based research including measurements of the Sun with respect to sun center. LASP has built sun position sensors for decades beginning with sensors for sub

  14. System for utilizing oil shale fines

    DOE Patents [OSTI]

    Harak, Arnold E. (Laramie, WY)

    1982-01-01

    A system is provided for utilizing fines of carbonaceous materials such as particles or pieces of oil shale of about one-half inch or less diameter which are rejected for use in some conventional or prior surface retorting process, which obtains maximum utilization of the energy content of the fines and which produces a waste which is relatively inert and of a size to facilitate disposal. The system includes a cyclone retort (20) which pyrolyzes the fines in the presence of heated gaseous combustion products, the cyclone retort having a first outlet (30) through which vapors can exit that can be cooled to provide oil, and having a second outlet (32) through which spent shale fines are removed. A burner (36) connected to the spent shale outlet of the cyclone retort, burns the spent shale with air, to provide hot combustion products (24) that are carried back to the cyclone retort to supply gaseous combustion products utilized therein. The burner heats the spent shale to a temperature which forms a molten slag, and the molten slag is removed from the burner into a quencher (48) that suddenly cools the molten slag to form granules that are relatively inert and of a size that is convenient to handle for disposal in the ground or in industrial processes.

  15. TECHNIQUES FOR THE STUDY OF THE STRUCTURAL PROPERTIES.

    SciTech Connect (OSTI)

    FERNANDEZ-GARCIA, M.; RODRIGUEZ, J.A.; MARTINEZ-ARIAS, A.; HANSON, J.C.

    2006-06-30

    The evolution of our understanding of the behavior of oxide nanostructures depends heavily on the structural information obtained from a wide range of physical methods traditionally used in solid state physics, surface science and inorganic chemistry. In this chapter, we describe several techniques that are useful for the characterization of the structural properties of oxide nanostructures: X-ray diffraction (XRD) and scattering, X-ray absorption fine structure (XAFS), Raman spectroscopy, transmission electron microscopy (TEM), scanning tunneling microscopy (STM) and atomic force microscopy (AFM). The ultimate goal is to obtain information about the spatial arrangement of atoms in the nanostructures with precise interatomic distances and bond angles. This may not be possible for complex systems and one may get only partial information about the local geometry or morphology.

  16. Absorption Heat Pumps | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Absorption Heat Pumps Absorption Heat Pumps June 24, 2012 - 2:11pm Addthis Absorption heat pumps are essentially air-source heat pumps driven not by electricity, but by a heat...

  17. Limits on Variations in Fundamental Constants from 21-cm and Ultraviolet Quasar Absorption Lines

    SciTech Connect (OSTI)

    Tzanavaris, P.; Webb, J.K.; Flambaum, V.V.; Curran, S.J.; Murphy, M.T.

    2005-07-22

    Quasar absorption spectra at 21-cm and UV rest wavelengths are used to estimate the time variation of x{identical_to}{alpha}{sup 2}g{sub p}{mu}, where {alpha} is the fine structure constant, g{sub p} the proton g factor, and m{sub e}/m{sub p}{identical_to}{mu} the electron/proton mass ratio. Over a redshift range 0.24 < or approx. z{sub abs} < or approx. 2.04, <{delta}x/x>{sub total}{sup weighted}=(1.17{+-}1.01)x10{sup -5}. A linear fit gives x/x=(-1.43{+-}1.27)x10{sup -15} yr{sup -1}. Two previous results on varying {alpha} yield the strong limits {delta}{mu}/{mu}=(2.31{+-}1.03)x10{sup -5} and {delta}{mu}/{mu}=(1.29{+-}1.01)x10{sup -5}. Our sample, 8x larger than any previous, provides the first direct estimate of the intrinsic 21-cm and UV velocity differences {approx}6 km s{sup -1}.

  18. Collision--induced absorption in dense atmospheres of cool stars

    SciTech Connect (OSTI)

    Borysow, Aleksandra; Joergensen, Uffe Graae

    1999-04-01

    In the atmosphere of the Sun the major interaction between the matter and the radiation is through light absorption by ions (predominantly the negative ion of hydrogen atoms), neutral atoms and a small amount of polar molecules. The majority of stars in the universe are, however, cooler and denser than our Sun, and for a large fraction of these, the above absorption processes are very weak. Here, collision-induced absorption (CIA) becomes the dominant opacity source. The radiation is absorbed during very short mutual passages ('collisions') of two non-polar molecules (and/or atoms), while their electric charge distributions are temporarily distorted which gives rise to a transient dipole moment. We present here a review of the present-day knowledge about the impact of collision-induced absorption processes on the structure and the spectrum of such stars.

  19. Combining X-ray Absorption and X-ray Diffraction Techniques for in Situ Studies of Chemical Transformations in Heterogeneous Catalysis: Advantages and Limitations

    SciTech Connect (OSTI)

    Frenkel, A.I.; Hanson, J.; Wang, Q.; Marinkovic, N.; Chen, J.G.; Barrio, L.; Si, R.; Lopez Camara, A.; Estrella, A.M.; Rodriguez, J.A.

    2011-08-05

    Recent advances in catalysis instrumentations include synchrotron-based facilities where time-resolved X-ray scattering and absorption techniques are combined in the same in situ or operando experiment to study catalysts at work. To evaluate the advances and limitations of this method, we performed a series of experiments at the new XAFS/XRD instrument in the National Synchrotron Light Source. Nearly simultaneous X-ray diffraction (XRD) and X-ray absorption fine-structure (XAFS) measurements of structure and kinetics of several catalysts under reducing or oxidizing conditions have been performed and carefully analyzed. For CuFe{sub 2}O{sub 4} under reducing conditions, the combined use of the two techniques allowed us to obtain accurate data on kinetics of nucleation and growth of metallic Cu. For the inverse catalyst CuO/CeO{sub 2} that underwent isothermal reduction (with CO) and oxidation (with O{sub 2}), the XAFS data measured in the same experiment with XRD revealed strongly disordered Cu species that went undetected by diffraction. These and other examples emphasize the unique sensitivity of these two complementary methods to follow catalytic processes in the broad ranges of length and time scales.

  20. Combining X-ray Absorption and X-ray Diffraction Techniques for in Situ Studies of Chemical Transformations in Heterogeneous Catalysis:Advantages and Limitations

    SciTech Connect (OSTI)

    A Frenkel; Q Wang; N Marinkovic; J Chen; L Barrio; R Si; A Lopez Camara; A Estella; J Rodriquez; J Hanson

    2011-12-31

    Recent advances in catalysis instrumentations include synchrotron-based facilities where time-resolved X-ray scattering and absorption techniques are combined in the same in situ or operando experiment to study catalysts at work. To evaluate the advances and limitations of this method, we performed a series of experiments at the new XAFS/XRD instrument in the National Synchrotron Light Source. Nearly simultaneous X-ray diffraction (XRD) and X-ray absorption fine-structure (XAFS) measurements of structure and kinetics of several catalysts under reducing or oxidizing conditions have been performed and carefully analyzed. For CuFe{sub 2}O{sub 4} under reducing conditions, the combined use of the two techniques allowed us to obtain accurate data on kinetics of nucleation and growth of metallic Cu. For the inverse catalyst CuO/CeO{sub 2} that underwent isothermal reduction (with CO) and oxidation (with O{sub 2}), the XAFS data measured in the same experiment with XRD revealed strongly disordered Cu species that went undetected by diffraction. These and other examples emphasize the unique sensitivity of these two complementary methods to follow catalytic processes in the broad ranges of length and time scales.

  1. For Cape Wind, Summer Breeze Makes Offshore Wind Feel Fine |...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    For Cape Wind, Summer Breeze Makes Offshore Wind Feel Fine For Cape Wind, Summer Breeze Makes Offshore Wind Feel Fine July 1, 2014 - 8:44am Addthis For Cape Wind, Summer Breeze...

  2. Synthesis of fine-grained TATB

    DOE Patents [OSTI]

    Lee, Kien-Yin (Santa Fe, NM); Kennedy, James E. (Santa Fe, NM)

    2003-04-15

    A method for producing fine-grained triamino-trinitrobenzene (TATB) powders having improved detonation-spreading performance and hence increased shock sensitivity when compared with that for ultrafine TATB is described. A single-step, sonochemical amination of trichloro-trinitrobenzene using ammonium hydroxide solution in a sealed vessel yields TATB having approximately 6 .mu.m median particle diameter and increased shock sensitivity.

  3. Process for treating moisture laden coal fines

    DOE Patents [OSTI]

    Davis, Burl E. (New Kensington, PA); Henry, Raymond M. (Gibsonia, PA); Trivett, Gordon S. (South Surrey, CA); Albaugh, Edgar W. (Birmingham, AL)

    1993-01-01

    A process is provided for making a free flowing granular product from moisture laden caked coal fines, such as wet cake, by mixing a water immiscible substance, such as oil, with the caked coal, preferably under low shear forces for a period of time sufficient to produce a plurality of free flowing granules. Each granule is preferably comprised of a dry appearing admixture of one or more coal particle, 2-50% by weight water and the water immiscible substance.

  4. Immobilization of Rocky Flats graphite fines residues

    SciTech Connect (OSTI)

    Rudisill, T.S.; Marra, J.C.; Peeler, D.K.

    1999-07-01

    The Savannah River Technology Center (SRTC) is developing an immobilization process for graphite fines residues generated during nuclear materials production activities at the Rocky Flats Environmental Technology Site (Rocky Flats). The continued storage of this material has been identified as an item of concern. The residue was generated during the cleaning of graphite casting molds and potentially contains reactive plutonium metal. The average residue composition is 73 wt% graphite, 15 wt% calcium fluoride (CaF{sub 2}), and 12 wt% plutonium oxide (PuO{sub 2}). Approximately 950 kg of this material are currently stored at Rocky Flats. The strategy of the immobilization process is to microencapsulate the residue by mixing with a sodium borosilicate (NBS) glass frit and heating at nominally 700 C. The resulting waste form would be sent to the Waste Isolation Pilot Plant (WIPP) for disposal. Since the PuO{sub 2} concentration in the residue averages 12 wt%, the immobilization process was required to meet the intent of safeguards termination criteria by limiting plutonium recoverability based on a test developed by Rocky Flats. The test required a plutonium recovery of less than 4 g/kg of waste form when a sample was leached using a nitric acid/CaF{sub 2} dissolution flowsheet. Immobilization experiments were performed using simulated graphite fines with cerium oxide (CeO{sub 2}) as a surrogate for PuO{sub 2} and with actual graphite fines residues. Small-scale surrogate experiments demonstrated that a 4:1 frit to residue ratio was adequate to prevent recovery of greater than 4 g/kg of cerium from simulated waste forms. Additional experiments investigated the impact of varying concentrations of CaF{sub 2} and the temperature/heating time cycle on the cerium recovery. Optimal processing conditions developed during these experiments were subsequently demonstrated at full-scale with surrogate materials and on a smaller scale using actual graphite fines.

  5. New Measurement Explores Fine Details of Proton Structure | Jefferson...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    contained 1,744 lead glass bars, such as the one shown, for detecting the scattered electrons. A collaboration of scientists is probing deep inside the proton at Jefferson Lab by...

  6. FOURIER ANALYSIS OF EXTENDED FINE STRUCTURE WITH AUTOREGRESSIVE PREDICTION

    E-Print Network [OSTI]

    Barton, J.

    2008-01-01

    ~ E. O. Brigham, The Fast Fourier Englewood Cliffs~ N.J. ~and sidelobe ratios for Fourier weighting functions. For aof ~k, the full width of the Fourier amplitude mainlobe for

  7. Fine spatiotemporal structure of phase in human intracranial EEG

    E-Print Network [OSTI]

    Freeman, Walter J III; Holmes, M D; West, G A; Vanhatalo, S

    2006-01-01

    Behav. 1968, 3: 597-599. Beggs JM and Plenz D. NeuronalHansen et al. [2001] and Beggs and Plenz [2004]. Aavalanches [Tsuda, 2001; Beggs and Plenz, 2004; Freeman,

  8. Discrimination of Low-Frequency Tones Employs Temporal Fine Structure

    E-Print Network [OSTI]

    Reichenbach, Tobias

    the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution was supported by grant DC000241 from the National Institutes of Health. T.R. holds a Career Award

  9. Topological Quantization in Units of the Fine Structure Constant (Journal

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaon and Pion decaysArticle)line integratedArticle)

  10. Topological Quantization in Units of the Fine Structure Constant (Journal

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaon and Pion decaysArticle)line integratedArticle)Article) | SciTech

  11. Fine density/design variable Computational Science and Engineering

    E-Print Network [OSTI]

    Paulino, Glaucio H.

    1400 1600 FE Analysis Optimization Initialization Buildings designed to minimize seismic or wind·Fine density/design variable mesh Computational Science and Engineering 2013 Annual Meeting.01 Fine design variable mesh Fine density variable mesh Comparison of forced vibration results 1

  12. Continuous fine-grained arm action recognition using motion spectrum

    E-Print Network [OSTI]

    Continuous fine-grained arm action recognition using motion spectrum mixture models Xi Zhao, it is necessary to recognise the fine-grained arm action during user interactions with other people or objects. A method to recognise a set of arm actions on a fine-grained level (e.g. checking the wristband, drinking

  13. Transient absorption spectroscopy of laser shocked explosives

    SciTech Connect (OSTI)

    Mcgrane, Shawn D; Dang, Nhan C; Whitley, Von H; Bolome, Cindy A; Moore, D S

    2010-01-01

    Transient absorption spectra from 390-890 nm of laser shocked RDX, PETN, sapphire, and polyvinylnitrate (PVN) at sub-nanosecond time scales are reported. RDX shows a nearly linear increase in absorption with time after shock at {approx}23 GPa. PETN is similar, but with smaller total absorption. A broad visible absorption in sapphire begins nearly immediately upon shock loading but does not build over time. PVN exhibits thin film interference in the absorption spectra along with increased absorption with time. The absorptions in RDX and PETN are suggested to originate in chemical reactions happening on picosecond time scales at these shock stresses, although further diagnostics are required to prove this interpretation.

  14. Near-infrared free carrier absorption in heavily doped silicon

    SciTech Connect (OSTI)

    Baker-Finch, Simeon C.; McIntosh, Keith R.; Yan, Di; Fong, Kean Chern; Kho, Teng C.

    2014-08-14

    Free carrier absorption in heavily doped silicon can have a significant impact on devices operating in the infrared. In the near infrared, the free carrier absorption process can compete with band to band absorption processes, thereby reducing the number of available photons to optoelectronic devices such as solar cells. In this work, we fabricate 18 heavily doped regions by phosphorus and boron diffusion into planar polished silicon wafers; the simple sample structure facilitates accurate and precise measurement of the free carrier absorptance. We measure and model reflectance and transmittance dispersion to arrive at a parameterisation for the free carrier absorption coefficient that applies in the wavelength range between 1000 and 1500?nm, and the range of dopant densities between ?10{sup 18} and 3?×?10{sup 20}?cm{sup ?3}. Our measurements indicate that previously published parameterisations underestimate the free carrier absorptance in phosphorus diffusions. On the other hand, published parameterisations are generally consistent with our measurements and model for boron diffusions. Our new model is the first to be assigned uncertainty and is well-suited to routine device analysis.

  15. Absorption-heat-pump system

    DOE Patents [OSTI]

    Grossman, G.; Perez-Blanco, H.

    1983-06-16

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  16. Observation of scattering and absorption centers in lead fluoride crystals

    E-Print Network [OSTI]

    Patrick Achenbach

    2006-06-22

    For the first time, lead fluoride is used as a fast and compact material in electromagnetic calorimetry. Excellent optical and mechanical properties of the pure Cherenkov crystals are necessary for the A4 collaboration to perform a measurement of the nucleon's strange form factors. Visible scattering and absorption centers as well as surface damages have been investigated to characterize the quality of more than one thousand crystals. Besides, transmittance measurements have been performed on all crystals to reveal absorption bands produced by intrinsic or impurity related point-structure defects. As a consequence, 89 crystals had to be replaced by the Chinese manufacturer SICCAS.

  17. Absorption and emission properties of photonic crystals and metamaterials

    SciTech Connect (OSTI)

    Peng, Lili

    2007-08-03

    We study the emission and absorption properties of photonic crystals and metamaterials using Comsol Multiphysics and Ansoft HFSS as simulation tools. We calculate the emission properties of metallic designs using drude model and the results illustrate that an appropriate termination of the surface of the metallic structure can significantly increase the absorption and therefore the thermal emissivity. We investigate the spontaneous emission rate modifications that occur for emitters inside two-dimensional photonic crystals and find the isotropic and directional emissions with respect to different frequencies as we have expected.

  18. Immobilization of Rocky Flats Graphite Fines Residues

    SciTech Connect (OSTI)

    Rudisill, T. S.

    1998-11-06

    The Savannah River Technology Center (SRTC) is developing an immobilization process for graphite fines residues generated during nuclear materials production activities at the Rocky Flats Environmental Technology Site (Rocky Flats). The continued storage of this material has been identified as an item of concern. The residue was generated during the cleaning of graphite casting molds and potentially contains reactive plutonium metal. The average residue composition is 73 wt percent graphite, 15 wt percent calcium fluoride (CaF2), and 12 wt percent plutonium oxide (PuO2). Approximately 950 kilograms of this material are currently stored at Rocky Flats. The strategy of the immobilization process is to microencapsulate the residue by mixing with a sodium borosilicate (NBS) glass frit and heating at nominally 700 degrees C. The resulting waste form would be sent to the Waste Isolation Pilot Plant (WIPP) for disposal. Since the PuO2 concentration in the residue averages 12 wt percent, the immobilization process was required to meet the intent of safeguards termination criteria by limiting plutonium recoverability based on a test developed by Rocky Flats. The test required a plutonium recovery of less than 4 g/kg of waste form when a sample was leached using a nitric acid/CaF2 dissolution flowsheet. Immobilization experiments were performed using simulated graphite fines with cerium oxide (CeO2) as a surrogate for PuO2 and with actual graphite fines residues. Small-scale surrogate experiments demonstrated that a 4:1 frit to residue ratio was adequate to prevent recovery of greater than 4 g/kg of cerium from simulated waste forms. Additional experiments investigated the impact of varying concentrations of CaF2 and the temperature/heating time cycle on the cerium recovery. Optimal processing conditions developed during these experiments were subsequently demonstrated at full-scale with surrogate materials and on a smaller scale using actual graphite fines.In general, the recovery of cerium from the full-scale waste forms was higher than for smaller scale experiments. The presence of CaF2 also caused a dramatic increase in cerium recovery not seen in the small-scale experiments. However, the results from experiments with actual graphite fines were encouraging. A 4:1 frit to residue ratio, a temperature of 700 degrees C, and a 2 hr heating time produced waste forms with plutonium recoveries of 4 plus/minus 1 g/kg. With an increase in the frit to residue ratio, waste forms fabricated at this scale should meet the Rocky Flats product specification. The scale-up of the waste form fabrication process to nominally 3 kg is expected to require a 5:1 to 6:1 frit to residue ratio and maintaining the waste form centerline temperature at 700 degrees C for 2 hr.

  19. The hydrogen-poor superluminous supernova iPTF 13ajg and its host galaxy in absorption and emission

    SciTech Connect (OSTI)

    Vreeswijk, Paul M.; Gal-Yam, Avishay; De Cia, Annalisa; Rubin, Adam; Yaron, Ofer; Tal, David; Ofek, Eran O.; Savaglio, Sandra; Quimby, Robert M.; Sullivan, Mark; Cenko, S. Bradley; Filippenko, Alexei V.; Clubb, Kelsey I.; Perley, Daniel A.; Cao, Yi; Taddia, Francesco; Sollerman, Jesper; Leloudas, Giorgos; Arcavi, Iair; Kasliwal, Mansi M.; and others

    2014-12-10

    We present imaging and spectroscopy of a hydrogen-poor superluminous supernova (SLSN) discovered by the intermediate Palomar Transient Factory, iPTF 13ajg. At a redshift of z = 0.7403, derived from narrow absorption lines, iPTF 13ajg peaked at an absolute magnitude of M {sub u,} {sub AB} = –22.5, one of the most luminous supernovae to date. The observed bolometric peak luminosity of iPTF 13ajg is 3.2 × 10{sup 44} erg s{sup –1}, while the estimated total radiated energy is 1.3 × 10{sup 51} erg. We detect narrow absorption lines of Mg I, Mg II, and Fe II, associated with the cold interstellar medium in the host galaxy, at two different epochs with X-shooter at the Very Large Telescope. From Voigt profile fitting, we derive the column densities log N(Mg I) =11.94 ± 0.06, log N(Mg II) =14.7 ± 0.3, and log N(Fe II) =14.25 ± 0.10. These column densities, as well as the Mg I and Mg II equivalent widths of a sample of hydrogen-poor SLSNe taken from the literature, are at the low end of those derived for gamma-ray bursts (GRBs) whose progenitors are also thought to be massive stars. This suggests that the environments of hydrogen-poor SLSNe and GRBs are different. From the nondetection of Fe II fine-structure absorption lines, we derive a lower limit on the distance between the supernova and the narrow-line absorbing gas of 50 pc. The neutral gas responsible for the absorption in iPTF 13ajg exhibits a single narrow component with a low velocity width, ?V = 76 km s{sup –1}, indicating a low-mass host galaxy. No host galaxy emission lines are detected, leading to an upper limit on the unobscured star formation rate (SFR) of SFR{sub [O} {sub II]}<0.07M{sub ?}yr{sup ?1}. Late-time imaging shows the iPTF 13ajg host galaxy to be faint, with g {sub AB} ? 27.0 and R {sub AB} ? 26.0 mag, corresponding to M {sub B,} {sub Vega} ? –17.7 mag.

  20. Probing variations in fundamental constants with radio and optical quasar absorption-line observations.

    SciTech Connect (OSTI)

    Tzanavaris, P.; Murphy, M. T.; Webb, J. K.; Flambaum, V. V.; Curran, S. J.; Physics; Univ. of New South Wales; Inst. of Astronomy

    2007-01-01

    Nine quasar absorption spectra at 21-cm and ultraviolet (UV) rest-frame wavelengths are used to estimate possible variations in x {triple_bond} {alpha}{sup 2}g{sub p}{mu}, where {alpha} is the fine structure constant, g{sub p} the proton g-factor and {mu} {triple_bond} m{sub e}/m{sub p} is the electron-to-proton mass ratio. We find <{Delta}x/x>{sub total}{sup weighted} = (0.63 {+-} 0.99) x 10{sup -5} over a redshift range 0.23 {le} z{sub abs} {le} 2.35 which corresponds to look-back times of 2.7-10.5 billion years. A linear fit against look-back time, tied to {Delta}x/x = 0 at z = 0, gives a best-fitting rate of change of {dot x}/x = (-0.6 {+-} 1.2) x 10{sup -5} yr{sup -1}. We find no evidence for strong angular variations in x across the sky. Our sample is much larger than most previous samples and demonstrates that intrinsic line-of-sight velocity differences between the 21-cm and UV absorption redshifts, which have a random sign and magnitude in each absorption system, limit our precision. The data directly imply that the average magnitude of this difference is {Delta}v{sub los}-6 km s{sup -1}. Combining our {Delta}x/x measurement with absorption-line constraints on {alpha}-variation yields strong limits on the variation of {mu}. Our most conservative estimate, obtained by assuming no variations in {alpha} or g{sub p} is simply {Delta}{mu}/{mu} = <{Delta}x/x>{sub total}{sup weighted}. If we use only the four high-redshift absorbers in our sample, we obtain {Delta}{mu}/{mu} = (0.58 {+-} 1.95) x 10{sup -5}, which agrees (2{sigma}) with recent, more direct estimates from two absorption systems containing molecular hydrogen, also at high redshift, and which have hinted at a possible {mu}-variation, {Delta}{mu}/{mu} = (-2.0 {+-} 0.6) x 10{sup -5}. Our method of constraining {Delta}{mu}/{mu} is completely independent from the molecular hydrogen observations. If we include the low-redshift systems, our {Delta}{mu}/{mu} result differs significantly from the high-redshift molecular hydrogen results. We detect a dipole variation in {mu} across the sky, but given the sparse angular distribution of quasar sight lines we find that this model is required by the data at only the 88 percent confidence level. Clearly, much larger samples of 21-cm and molecular hydrogen absorbers are required to adequately resolve the issue of the variation of {mu} and x.

  1. Self-consistent QM/MM methodologies for structural refinement of photosystem II and other macromolecules of biological interest

    SciTech Connect (OSTI)

    Batista, Enrique R [Los Alamos National Laboratory; Sproviero, Eduardo M [YALE UNIV; Newcomer, Michael [YALE UNIV; Gascon, Jose A [YALE UNIV; Batista, Victor S [YALE UNIV

    2008-01-01

    The combination of quantum mechanics and molecular mechanics (QM/MM) is one of the most promising approaches to study the structure, function, and properties of proteins and nucleic acids. However, there some instances in which the limitations of either the MM (lack of a proper electronic description) or QM (limited to a few number of atoms) methods prevent a proper description of the system. To address this issue, we review here our approach to fine-tune the structure of biological systems using post-QM/MM refinements. These protocols are based on spectroscopy data, and/or partitioning of the system to extend the QM description to a larger region of a protein. We illustrate these methodologies through applications to several biomolecules, which were pre-optimized at the QM/MM level and then further refined using postQM/MM refinement methodologies: mod(QM/MM), which refines the atomic charges of the residues included in the MM region accounting for polarization effects; mod(QM/MM)-opt that partition the MM region in smaller parts and optimizes each part in an iterative. self-consistent way, and the Polarized-Extended X-Ray Absorption Fine Structure (P-EXAFS) fitting procedure, which fine-tune the atomic coordinates to reproduce experimental polarized EXAFS spectra. The first two techniques were applied to the guanine quadruplex. while the P-EXAFS refinement was applied to the oxygen evolving complex of photosystem II.

  2. Photodetector with enhanced light absorption

    DOE Patents [OSTI]

    Kane, James (Lawrenceville, NJ)

    1985-01-01

    A photodetector including a light transmissive electrically conducting layer having a textured surface with a semiconductor body thereon. This layer traps incident light thereby enhancing the absorption of light by the semiconductor body. A photodetector comprising a textured light transmissive electrically conducting layer of SnO.sub.2 and a body of hydrogenated amorphous silicon has a conversion efficiency about fifty percent greater than that of comparative cells. The invention also includes a method of fabricating the photodetector of the invention.

  3. Moisture absorption in hybrid composites 

    E-Print Network [OSTI]

    Clark, Dan Laro

    1983-01-01

    Moisture Analysis for Steady State Boundary Conditions", Journal of Com osite Materials, Vol. 15, March 1981, pp. 142-152. 7. Weitsman, Y. , Priorate Communication, Texas A&M University, January 1983. 8. Wirth, Patricia E. and Rodin, Ervin Y. , "A... of Department) December 1983 111. ABSTRACT Moisture Absorption in Hybrid Composites (December 1983) Dan Laro Clark, B. S. Aerospace Engineering Texas A&M University Co-Chairmen of Advisory Comnittee: Dr. Y. Weitsman Dr. W. J. Horn This thesis presents...

  4. Manganese valence and coordination structure in Mn,Mg-codoped {gamma}-AlON green phosphor

    SciTech Connect (OSTI)

    Takeda, Takashi; Xie, Rong-Jun; Hirosaki, Naoto; Matsushita, Yoshitaka; Honma, Tetuso

    2012-10-15

    The valence and coordination structure of manganese in a Mn,Mg-codoped {gamma}-AlON spinel-type oxynitride green phosphor were studied by synchrotron X-ray diffraction and absorption fine structure measurements. The absorption edge position of the XANES revealed the bivalency of Mn. Two cation sites are available in the spinel structure for cation doping: a tetrahedral site and an octahedral site. The pre-edge of the XANES and the distance to the nearest neighbor atoms obtained from the EXAFS measurement showed that Mn was situated at the tetrahedral site. Rietveld analysis showed that the vacancy occupied the octahedral site. The preferential occupation of the tetrahedral site by Mn and the roles of N and Mg are discussed in relation to the spinel crystal structure. - Graphical Abstract: Fourier transform of EXAFS of Mn K-edge for Mn,Mg-codoped green phosphor and Mn coordination structure. Highlights: Black-Right-Pointing-Pointer Mn, Mg-codoped {gamma}-AlON green phosphor for white LED. Black-Right-Pointing-Pointer The valence of Mn is divalent. Black-Right-Pointing-Pointer Mn occupies the tetrahedral site in the spinel structure.

  5. Control of acoustic absorption in 1D scattering by indirect coupled resonant scatterers

    E-Print Network [OSTI]

    Merkel, A; Richoux, O; Romero-García, V; Pagneux, V

    2015-01-01

    We experimentally report perfect acoustic absorption through the interplay of the inherent losses and transparent modes with high $Q$ factor. These modes are generated in a two-port, one-dimensional waveguide which is side-loaded by isolated resonators of moderate $Q$ factor. In symmetric structures, we show that in the presence of small inherent losses, these modes lead to coherent perfect absorption associated with one-sided absorption slightly larger than 0.5. In asymmetric structures, near perfect one-sided absorption is possible (96 \\%) with a deep sub-wavelength sample ($\\lambda/28$). The control of strong absorption by the proper tuning of few resonators with weak losses will open new possibilities in various wave-control devices.

  6. Local structures surrounding Zr in nanostructurally stabilized cubic zirconia: Structural origin of phase stability

    SciTech Connect (OSTI)

    Soo, Y. L.; Chen, P. J.; Huang, S. H.; Shiu, T. J.; Tsai, T. Y.; Chow, Y. H.; Lin, Y. C.; Weng, S. C.; Chang, S. L. [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Wang, G.; Cheung, C. L. [Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588 (United States); Sabirianov, R. F.; Mei, W. N. [Department of Physics, University of Nebraska at Omaha, Omaha, Nebraska 68182 (United States); Namavar, F.; Haider, H.; Garvin, K. L. [Department of Orthopaedics Surgery and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska 68198 (United States); Lee, J. F. [National Synchrotron Radiation Research Center, Hsinchu 30013, Taiwan (China); Lee, H. Y.; Chu, P. P. [Department of Chemistry, National Central University, Jhongli 32001, Taiwan (China)

    2008-12-01

    Local environment surrounding Zr atoms in the thin films of nanocrystalline zirconia (ZrO{sub 2}) has been investigated by using the extended x-ray absorption fine structure (EXAFS) technique. These films prepared by the ion beam assisted deposition exhibit long-range structural order of cubic phase and high hardness at room temperature without chemical stabilizers. The local structure around Zr probed by EXAFS indicates a cubic Zr sublattice with O atoms located on the nearest tetragonal sites with respect to the Zr central atoms, as well as highly disordered locations. Similar Zr local structure was also found in a ZrO{sub 2} nanocrystal sample prepared by a sol-gel method. Variations in local structures due to thermal annealing were observed and analyzed. Most importantly, our x-ray results provide direct experimental evidence for the existence of oxygen vacancies arising from local disorder and distortion of the oxygen sublattice in nanocrystalline ZrO{sub 2}. These oxygen vacancies are regarded as the essential stabilizing factor for the nanostructurally stabilized cubic zirconia.

  7. Advanced regenerative absorption refrigeration cycles

    DOE Patents [OSTI]

    Dao, Kim (14 Nace Ave., Piedmont, CA 94611)

    1990-01-01

    Multi-effect regenerative absorption cycles which provide a high coefficient of performance (COP) at relatively high input temperatures. An absorber-coupled double-effect regenerative cycle (ADR cycle) (10) is provided having a single-effect absorption cycle (SEA cycle) (11) as a topping subcycle and a single-effect regenerative absorption cycle (1R cycle) (12) as a bottoming subcycle. The SEA cycle (11) includes a boiler (13), a condenser (21), an expansion device (28), an evaporator (31), and an absorber (40), all operatively connected together. The 1R cycle (12) includes a multistage boiler (48), a multi-stage resorber (51), a multisection regenerator (49) and also uses the condenser (21), expansion device (28) and evaporator (31) of the SEA topping subcycle (11), all operatively connected together. External heat is applied to the SEA boiler (13) for operation up to about 500 degrees F., with most of the high pressure vapor going to the condenser (21) and evaporator (31) being generated by the regenerator (49). The substantially adiabatic and isothermal functioning of the SER subcycle (12) provides a high COP. For higher input temperatures of up to 700 degrees F., another SEA cycle (111) is used as a topping subcycle, with the absorber (140) of the topping subcycle being heat coupled to the boiler (13) of an ADR cycle (10). The 1R cycle (12) itself is an improvement in that all resorber stages (50b-f) have a portion of their output pumped to boiling conduits (71a-f) through the regenerator (49), which conduits are connected to and at the same pressure as the highest pressure stage (48a) of the 1R multistage boiler (48).

  8. Controlling formation fines at their sources to maintain well productivity

    SciTech Connect (OSTI)

    Nguyen, P.D.; Weaver, J.D.; Rickman, R.D.; Dusterhoft, R.G.; Parker, M.A.

    2007-05-15

    Migration of formation fines has been shown to cause production decline in many wells. Despite the availability of new downhole tools for use in well stimulation and completion, the ability to sustain desired production levels is often plagued with fines migration problems. The solution to this problem is appropriate treatment to mitigate fines migration at its source. This paper describes the use of an ultra-thin tackifying agent (UTTA) for stabilizing fines in high-rate producing or injection wells. This UTTA is applied as part of an initial prepad in fracturing or gravel-packing operations, as a remedial treatment, or as a post-treatment following acid fracturing or matrix acidizing treatments. The primary purpose of UTTA application is to immobilize formation fines so that they will not detach, migrate with flowing fluids, plug the pore channels, and reduce the flow path permeability. Results of laboratory testing indicate that the UTTA system is applicable to most types of formation fines, including coals, sandstones, and carbonates. Once injected into the formation matrix or proppant pack, the UTTA forms a thin film on formation surfaces, encapsulating the fines. Capillary action helps pull the tackifier into the contact points, fixing the particulate in place without plugging the pore throat. The UTTA does not require a shut-in time after its application. The thin film tackifier does not harden, but remains flexible, enhancing the ability of a formation to withstand stress cycling and allowing the formation to handle high shear stress during high flow rates.

  9. Olefin recovery via chemical absorption

    SciTech Connect (OSTI)

    Barchas, R.

    1998-06-01

    The recovery of fight olefins in petrochemical plants has generally been accomplished through cryogenic distillation, a process which is very capital and energy intensive. In an effort to simplify the recovery process and reduce its cost, BP Chemicals has developed a chemical absorption technology based on an aqueous silver nitrate solution. Stone & Webster is now marketing, licensing, and engineering the technology. The process is commercially ready for recovering olefins from olefin derivative plant vent gases, such as vents from polyethylene, polypropylene, ethylene oxide, and synthetic ethanol units. The process can also be used to debottleneck C{sub 2} or C{sub 3} splinters, or to improve olefin product purity. This paper presents the olefin recovery imp technology, discusses its applications, and presents economics for the recovery of ethylene and propylene.

  10. Electronic structure of nitinol surfaces oxidized by low-energy ion bombardment

    SciTech Connect (OSTI)

    Petravic, M. Varasanec, M.; Peter, R.; Kavre, I.; Metikos-Hukovic, M.; Yang, Y.-W.

    2014-06-28

    We have studied the electronic structure of nitinol exposed to low-energy oxygen-ion bombardment, using x-ray photoemission spectroscopy (XPS) and near-edge x-ray absorption fine structure (NEXAFS) spectroscopy. XPS spectra reveal a gradual transformation of nitinol surfaces into TiO{sub 2} with increased dose of implanted oxygen. No oxidation of Ni atoms has been detected. NEXAFS spectra around O K-edge and Ti L{sub 2,3}-edge, reflecting the element-specific partial density of empty electronic states, exhibit features, which can be attributed to the creation of molecular orbitals, crystal field splitting, and the absence of long-range order, characteristic of the amorphous TiO{sub 2}. Based on these results, we discuss the oxidation kinetics of nitinol under low-energy oxygen-ion bombardment.

  11. HI emission and absorption in nearby, gas-rich galaxies

    E-Print Network [OSTI]

    Reeves, S N; Allison, J R; Koribalski, B S; Curran, S J; Pracy, M B

    2015-01-01

    We present the results of a targeted search for intervening HI absorption in six nearby, gas-rich galaxies using the Australia Telescope Compact Array (ATCA). The sightlines searched have impact parameters of 10-20 kpc. By targeting nearby galaxies we are also able to map their HI emission, allowing us to directly relate the absorption-line detection rate to the extended HI distribution. The continuum sightlines intersect the HI disk in four of the six galaxies, but no intervening absorption was detected. Of these four galaxies, we find that three of the non-detections are the result of the background source being too faint. In the fourth case we find that the ratio of the spin temperature to the covering factor ($T_{\\mathrm{S}}/f$) must be much higher than expected ($\\gtrsim$5700 K) in order to explain the non-detection. We discuss how the structure of the background continuum sources may have affected the detection rate of HI absorption in our sample, and the possible implications for future surveys. Future...

  12. Combining Feedback Absorption Spectroscopy, Amplified Resonance...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    On-Board Measurement of Ammonia and Nitrous Oxide Using Feedback Absorption Laser Spectroscopy Combined with Amplified Resonance and Low Pressure Sampling Cummins...

  13. Advanced Low Temperature Absorption Chiller Module Integrated...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Low Temperature Absorption Chiller Module Integrated with a CHP System at a Distributed Data Center - Presentation by Exergy Partners Corp., June 2011 Advanced Low Temperature...

  14. Direct and quantitative absorptive spectroscopy of nanowires

    E-Print Network [OSTI]

    Tong, Jonathan Kien-Kwok

    2012-01-01

    Photonic nanostructures exhibit unique optical properties that are attractive in many different applications. However, measuring the optical properties of individual nanostructures, in particular the absorptive properties, ...

  15. Soft X-ray Spectroscopy Study of the Electronic Structure of Oxidized and Partially Oxidized Magnetite Nanoparticles

    SciTech Connect (OSTI)

    Gilbert, Benjamin; Katz, Jordan E.; Denlinger, Jonathan D.; Yin, Yadong; Falcone, Roger; Waychunas, Glenn A.

    2010-10-24

    The crystal structure of magnetite nanoparticles may be transformed to maghemite by complete oxidation, but under many relevant conditions the oxidation is partial, creating a mixed-valence material with structural and electronic properties that are poorly characterized. We used X-ray diffraction, Fe K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy, and soft X-ray absorption and emission spectroscopy to characterize the products of oxidizing uncoated and oleic acid-coated magnetite nanoparticles in air. The oxidization of uncoated magnetite nanoparticles creates a material that is structurally and electronically indistinguishable from maghemite. By contrast, while oxidized oleic acid-coated nanoparticles are also structurally indistinguishable from maghemite, Fe L-edge spectroscopy revealed the presence of interior reduced iron sites even after a 2-year period. We used X-ray emission spectroscopy at the O K-edge to study the valence bands (VB) of the iron oxide nanoparticles, using resonant excitation to remove the contributions from oxygen atoms in the ligands and from low-energy excitations that obscured the VB edge. The bonding in all nanoparticles was typical of maghemite, with no detectable VB states introduced by the long-lived, reduced-iron sites in the oleic acid-coated sample. However, O K-edge absorption spectroscopy observed a 0.2 eV shift in the position of the lowest unoccupied states in the coated sample, indicating an increase in the semiconductor band gap relative to bulk stoichiometric maghemite that was also observed by optical absorption spectroscopy. The results show that the ferrous iron sites within ferric iron oxide nanoparticles coated by an organic ligand can persist under ambient conditions with no evidence of a distinct interior phase and can exert an effect on the global electronic and optical properties of the material. This phenomenon resembles the band gap enlargement caused by electron accumulation in the conduction band of TiO2.

  16. A Finely-Predicted Higgs Boson Mass from A Finely-Tuned Weak Scale

    E-Print Network [OSTI]

    Lawrence J. Hall; Yasunori Nomura

    2009-10-19

    If supersymmetry is broken directly to the Standard Model at energies not very far from the unified scale, the Higgs boson mass lies in the range 128-141 GeV. The end points of this range are tightly determined. Theories with the Higgs boson dominantly in a single supermultiplet predict a mass at the upper edge, (141 \\pm 2) GeV, with the uncertainty dominated by the experimental errors on the top quark mass and the QCD coupling. This edge prediction is remarkably insensitive to the supersymmetry breaking scale and to supersymmetric threshold corrections so that, in a wide class of theories, the theoretical uncertainties are at the level of \\pm 0.4 GeV. A reduction in the uncertainties from the top quark mass and QCD coupling to the level of \\pm 0.3 GeV may be possible at future colliders, increasing the accuracy of the confrontation with theory from 1.4% to 0.4%. Verification of this prediction would provide strong evidence for supersymmetry, broken at a very high scale of ~ 10^{14 \\pm 2} GeV, and also for a Higgs boson that is elementary up to this high scale, implying fine-tuning of the Higgs mass parameter by ~ 20-28 orders of magnitude. Currently, the only known explanation for such fine-tuning is the multiverse.

  17. EVALUATION OF VARIOUS FABRICATION TECHNIQUES FOR FABRICATION OF FINE FILAMENT NbTi SUPERCONDUCTORS

    E-Print Network [OSTI]

    Scanlan, R.M.

    2010-01-01

    i c Formation in Fine Filament Nb-Ti Superconductors," lEEK~ of closely spaced fine filaments. Refe ~ences "HanufactureFOR FABRICATION OF FINE FILAMENT NbTi SUPERCONDUCTORS R.M.

  18. Effect of morphology and solvent on two-photon absorption of nano zinc oxide

    SciTech Connect (OSTI)

    Kavitha, M.K. [Department of Chemistry, Indian Institute of Space Science and Technology, Valiamala, Thiruvananthapuram 695547, Kerala (India); Haripadmam, P.C.; Gopinath, Pramod; Krishnan, Bindu [Department of Physics, Indian Institute of Space Science and Technology, Valiamala, Thiruvananthapuram 695547, Kerala (India); John, Honey, E-mail: honey@iist.ac.in [Department of Chemistry, Indian Institute of Space Science and Technology, Valiamala, Thiruvananthapuram 695547, Kerala (India)

    2013-05-15

    Highlights: ? ZnO nanospheres and triangular structures synthesis by novel precipitation technique. ? The effect of precursor concentration on the size and shape of nano ZnO. ? Open aperture Z-scan measurements of the ZnO nanoparticle dispersions. ? Nanospheres exhibit higher two photon absorption coefficient than triangular nanostructures. ? Nanospheres dispersed in water exhibit higher two photon absorption coefficient than its dispersion in 2-propanol. - Abstract: In this paper, we report the effect of morphology and solvent on the two-photon absorption of nano zinc oxide. Zinc oxide nanoparticles in two different morphologies like nanospheres and triangular nanostructures are synthesized by novel precipitation technique and their two-photon absorption coefficient is measured using open aperture Z-scan technique. Experimental results show that the zinc oxide nanospheres exhibit higher two-photon absorption coefficient than the zinc oxide triangular nanostructures. The zinc oxide nanospheres dispersed in water exhibit higher two-photon absorption coefficient than that of its dispersion in 2-propanol. The zinc oxide nanospheres dispersed in water shows a decrease in two-photon absorption coefficient with an increase in on-axis irradiance. The result confirms the dependence of shape and solvent on the two-photon absorption of nano zinc oxide.

  19. Pseudopotential calculations and photothermal lensing measurements of two-photon absorption in solids

    SciTech Connect (OSTI)

    White, W.T. III

    1985-11-04

    We have studied two-photon absorption in solids theoretically and experimentally. We have shown that it is possible to use accurate band structure techniques to compute two-photon absorption spectra within 15% of measured values in a wide band-gap material, ZnS. The empirical pseudopotential technique that we used is significantly more accurate than previous models of two-photon absorption in zinc blende materials, including present tunneling theories (which are essentially parabolic-band results in disguise) and the nonparabolic-band formalism of Pidgeon et al. and Weiler. The agreement between our predictions and previous measurements allowed us to use ZnS as a reference material in order to validate a technique for measuring two-photon absorption that was previously untried in solids, pulsed dual-beam thermal lensing. With the validated technique, we examined nonlinear absorption in one other crystal (rutile) and in several glasses, including silicates, borosilicates, and one phosphate glass. Initially, we believed that the absorption edges of all the materials were comparable; however, subsequent evidence suggested that the effective band-gap energies of the glasses were above the energy of two photons in our measurement. Therefore, we attribute the nonlinear absorption that we observed in glasses to impurities or defects. The measured nonlinear absorption coefficients were of the order of a few cm/TW in the glasses and of the order of 10 cm/GW in the crystals, four orders of magnitude higher than in glasses. 292 refs.

  20. Nontoxic chemical process for in situ permeability enhancement and accelerated decontamination of fine-grain subsurface sediments

    DOE Patents [OSTI]

    Kansa, E.J.; Wijesinghe, A.M.; Viani, B.E.

    1997-01-14

    The remediation of heterogeneous subsurfaces is extremely time consuming and expensive with current and developing technologies. Although such technologies can adequately remove contaminants in the high hydraulic conductivity, coarse-grained sediments, they cannot access the contaminated low hydraulic conductivity fine-grained sediments. The slow bleed of contaminants from the fine-grained sediments is the primary reason why subsurface remediation is so time-consuming and expensive. This invention addresses the problem of remediating contaminated fine-grained sediments. It is intended that, in the future, a heterogeneous site be treated by a hybrid process that first remediates the high hydraulic conductivity, coarse-grained sediments, to be followed by the process, described in this invention, to treat the contaminated low hydraulic conductivity fine-grained sediments. The invention uses cationic flocculants and organic solvents to collapse the swelling negative double layer surrounding water saturated clay particles, causing a flocculated, cracked clay structure. The modification of the clay fabric in fine-grained sediments dramatically increases the hydraulic conductivity of previously very tight clays many orders of magnitude. 8 figs.

  1. Nontoxic chemical process for in situ permeability enhancement and accelerated decontamination of fine-grain subsurface sediments

    DOE Patents [OSTI]

    Kansa, Edward J. (Livermore, CA); Wijesinghe, Ananda M. (Tracy, CA); Viani, Brian E. (Oakland, CA)

    1997-01-01

    The remediation of heterogeneous subsurfaces is extremely time consuming and expensive with current and developing technologies. Although such technologies can adequately remove contaminants in the high hydraulic conductivity, coarse-grained sediments, they cannot access the contaminated low hydraulic conductivity fine-grained sediments. The slow bleed of contaminants from the fine-grained sediments is the primary reason why subsurface remediation is so time-consuming and expensive. This invention addresses the problem of remediating contaminated fine-grained sediments. It is intended that, in the future, a heterogeneous site be treated by a hybrid process that first remediates the high hydraulic conductivity, coarse-grained sediments, to be followed by the process, described in this invention, to treat the contaminated low hydraulic conductivity fine-grained sediments. The invention uses cationic flocculents and organic solvents to collapse the swelling negative double layer surrounding water saturated clay particles, causing a flocculated, cracked clay structure. The modification of the clay fabric in fine-grained sediments dramatically increases the hydraulic conductivity of previously very tight clays many orders of magnitude.

  2. Methodology for Fine Art formulation applied to investment casting moulds 

    E-Print Network [OSTI]

    Ibrahim, Ahmad Rashdi Yan

    This research concerns the development of a methodology for formulation in Fine Art, Design and Craft practice. The methodology is applied to the choosing of formulations for bronze and glass investments casting moulds ...

  3. Modified approaches for high pressure filtration of fine clean coal

    SciTech Connect (OSTI)

    Yang, J.; Groppo, J.G.; Parekh, B.K. [Center for Applied Energy Research, Lexington, KY (United States)

    1995-12-31

    Removal of moisture from fine (minus 28 mesh) clean coal to 20% or lower level is difficult using the conventional vacuum dewatering technique. High pressure filtration technique provides an avenue for obtaining low moisture in fine clean coal. This paper describes a couple of novel approaches for dewatering of fine clean coal using pressure filtration which provides much lower moisture in fine clean coal than that obtained using conventional pressure filter. The approaches involve (a) split stream dewatering and (b) addition of paper pulp to the coal slurry. For Pittsburgh No. 8 coal slurry, split stream dewatering at 400 mesh provided filter cake containing 12.9% moisture compared to 24.9% obtained on the feed material. The addition of paper pulp to the slurry provided filter cake containing about 17% moisture.

  4. Deadlock-free fine-grained thread migration

    E-Print Network [OSTI]

    Cho, Myong Hyon

    Several recent studies have proposed fine-grained, hardware-level thread migration in multicores as a solution to power, reliability, and memory coherence problems. The need for fast thread migration has been well documented, ...

  5. Power generation with laterally packaged piezoelectric fine wires

    E-Print Network [OSTI]

    Wang, Zhong L.

    Power generation with laterally packaged piezoelectric fine wires Rusen Yang1 , Yong Qin1 , Liming we report a flexible power generator that is based on cyclic stretching­releasing of a piezoelectric

  6. MICROSTRUCTURE AND PROPERTIES OF DUAL PHASE STEELS CONTAINING FINE PRECIPITATES

    E-Print Network [OSTI]

    Gau, J.S.

    2014-01-01

    and Properties of Dual-Phase Steels, R. A. Kot and J. W.of Niobium Microalloyed Dual- Phase Steel, MetallurgicalAND PROPERTIES OF DUAL PHASE STEELS CONTAINING FINE

  7. High Energy Astrophysics: Emission and Absorption 1/114 Emission and Absorption

    E-Print Network [OSTI]

    Bicknell, Geoff

    High Energy Astrophysics: Emission and Absorption 1/114 Emission and Absorption 1 Motivation and the jet. #12;High Energy Astrophysics: Emission and Absorption 2/114 HST optical image of 3C273 Note the very strong cen- tral point source and the less luminous jet. Objects such as 3C273 radiate as much

  8. Enhancing Android Accessibility for Users with Hand Tremor by Reducing Fine Pointing and Steady Tapping

    E-Print Network [OSTI]

    Cortes, Corinna

    Enhancing Android Accessibility for Users with Hand Tremor by Reducing Fine Pointing and Steady; magnification; Android; disambiguation; fine pointing; steady tapping. ACM Classification Keywords H.5

  9. Cross section for charmonium absorption by nucleons 

    E-Print Network [OSTI]

    Liu, W.; Ko, Che Ming; Lin, ZW.

    2002-01-01

    The cross section for J/psi absorption by nucleons is studied using a gauged SU(4) hadronic Lagrangian but with empirical particle masses, which has been used previously to study the cross sections for J/psi absorption by pion and rho meson...

  10. INCREASED LEAD ABSORPTION AND LEAD POISONING

    E-Print Network [OSTI]

    INCREASED LEAD ABSORPTION AND LEAD POISONING IN YOUNG CHILDREN A STATDIE:"IT BY THE CEJde slnt:t! the Surgeon GenerJi's Statement. "~edicJI Aspects of Childhood Lead POisoning," was issued:ld absorption Jnd lead poisoning. Such JCtivities for children will continue to be necessary until sources

  11. Absorption of carbonyl sulfide in aqueous methyldiethanolamine

    SciTech Connect (OSTI)

    Al-Ghawas, H.A.; Ruiz-Ibanez, G.; Sandall, O.C. (Dept. of Chemical and Nuclear Engineering, Univ. of California, Santa Barbara, CA (US))

    1988-01-01

    The absorption of carbonyl sulfide in aqueous methyldiethanolamine (MDEA) was studied over a range of temperatures and MDEA concentrations. MDEA is commonly used for selective absorption of hydrogen sulfide in the presence of carbon dioxide. However, sulfur in the form of COS may also be present and it is necessary that estimates of absorption rates of this compound be made. The objective of this study is to determine the physiochemical properties needed to predict COS absorption rates in aqueous MDEA. Free gas solubility and the diffusivity of COS in MDEA solutions were measured over the temperature range 15 to 40{sup 0}C for MDEA concentrations up to 30 weight per cent using the nitrous oxide analogy method. Solubilities were measured volumetrically in an equilibrium cell and diffusivities were measured using a laminar liquid jet absorber. The kinetics of the reaction between COS and MDEA were studied by measuring absorption rates in a single wetted-sphere absorber.

  12. Influence of structural disorder on soft x-ray optical behavior of NbC thin films

    SciTech Connect (OSTI)

    Singh, Amol E-mail: rrcat.amol@gmail.com; Modi, Mohammed H.; Sinha, A. K.; Lodha, G. S.; Rajput, Parasmani

    2015-05-07

    Structural and chemical properties of compound materials are modified, when thin films are formed from bulk materials. To understand these changes, a study was pursued on niobium carbide (NbC) thin films of different thicknesses deposited on Si (100) substrate using ion beam sputtering technique. Optical response of the film was measured in 4–36?nm wavelength region using Indus-1 reflectivity beamline. A discrepancy in soft x-ray performance of NbC film was observed which could not be explained with Henke's tabulated data (see http://henke.lbl.gov/optical{sub c}onstants/ ). In order to understand this, detailed structural and chemical investigations were carried out using x-ray reflectivity, grazing incidence x-ray diffraction, x-ray absorption near edge structure, extended x-ray absorption fine structure, and x-ray photoelectron spectroscopy techniques. It was found that the presence of unreacted carbon and Nb deficiency due to reduced Nb-Nb coordination are responsible for lower soft x-ray reflectivity performance. NbC is an important material for soft x-ray optical devices, hence the structural disorder need to be controlled to achieve the best performances.

  13. Local structure underlying anomalous tetragonal distortions in BiFeO{sub 3}-PbTiO{sub 3} ferroelectrics

    SciTech Connect (OSTI)

    Levin, I.; Krayzman, V.; Woicik, J. C.; Tucker, M. G.

    2014-06-16

    The local structure of tetragonal BiFeO{sub 3}-PbTiO{sub 3} solid solutions featuring anomalous lattice distortions has been determined using simultaneous fitting of neutron total scattering and extended X-ray absorption fine structure data. On the local scale, the large tetragonal distortion, promoted by the displacements of the A-cations (Bi and Pb), is accommodated primarily by the [FeO{sub 6}] octahedra, even though both Fe and Ti acquire (5+1)-fold coordination. Bi cations exhibit considerably larger displacements than Pb. The combination of the A-cation displacements and the ability of M-cations to adopt 5-fold coordination is suggested as key for stabilizing the large tetragonality in BiMO{sub 3}-PbTiO{sub 3} systems.

  14. Magnetic and Electronic Structure study of Fe/MgO/Fe/Co Multilayer Stack Deposited by E-Beam Evaporation

    E-Print Network [OSTI]

    Jitendra Pal Singh; Sanjeev Gautam; Braj Bhusan Singh; M. Raju; S. Chaudhary; D. Kabiraj; D. Kanjilal; Jenn-Min Lee; Jin-Ming Chen; K. Asokan; Keun Hwa Chae

    2013-05-13

    Present work investigates the magnetic and electronic structure of MgO/Fe/MgO/Fe/Co/Au multilayer stack grown on Si(100) substrates by electron beam evaporation method. X-ray diffraction study depicts polycrystalline nature of the multilayers. Results obtained from vibrating sample magnetometry (VSM) and near-edge X-ray absorption fine structure spectra (NEXAFS) at Fe & Co L- and Mg & O K-edges are applied to understand the magnetic and electronic properties of this stack and its interface properties. While the spectral features of Fe L-edge spectrum recorded by surface sensitive total electron yield (TEY) mode shows the formation of FeOx at the Fe/MgO interface, the bulk sensitive total fluorescence yield (TFY), shows Fe in metallic nature. Co L-edge spectrum reveals the presence of metallic nature of cobalt in both TEY and TFY modes. Above results are well correlated with X-ray reflectometry.

  15. A New Model of Fine Sediment Transport For the Fraser River

    E-Print Network [OSTI]

    #12;A New Model of Fine Sediment Transport For the Fraser River DOE FRAP 1996-17 Prepared for Fine sediments of the Fraser River play an important role in the transportation of contaminants ACTION PLAN. The existing models of fine sediment transport assume that the fine sediments behave

  16. Absorptive Recycle of Distillation Waste Heat 

    E-Print Network [OSTI]

    Erickson, D. C.; Lutz, E. J., Jr.

    1982-01-01

    condenser operates above ambient temperature, the rejected heat also contains unused availability. By incorporating an absorption heat pump (AHP) into the distillation process, these sources of unused availability can be tapped so as to recycle (and hence...

  17. Energy Saving with Absorption Refrigeration Technologies 

    E-Print Network [OSTI]

    Davis, R. C.

    1984-01-01

    generally been overlooked by the process industry. This paper will address the application of the lithium bromide-water cycle in various energy saving modes. A waste heat powered absorption chiller producing chilled water can reduce energy consumption in a...

  18. Absorption Heat Pumps | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    an ammonia-water absorption cycle to provide heating and cooling. As in a standard heat pump, the refrigerant (in this case, ammonia) is condensed in one coil to release its...

  19. Absorption chillers: Part of the solution

    SciTech Connect (OSTI)

    Occhionero, A.J. (American Gas Cooling Center, Arlington, VA (United States)); Hughes, P.J. (Oak Ridge National Lab., TN (United States)); Reid, E.A. (Columbia Gas Distribution Co., Columbus, OH (United States))

    1991-01-01

    Acid rain, ozone depletion, global warming, and implementation economics are considered as they relate to the advisability of expanding the application of absorption chillers. Introductory and background information are provided to put the discussion in the proper context. Then all four issues are discussed separately as they relate to absorption chillers. Acid rain and ozone depletion concerns, and implementation economics, are found to support the expanded use of absorption chillers. The global warming concern is found to be more of a gray area, but the areas of benefit correspond well with the conditions of greatest economic advantage. All things considered, absorption chillers are believed to be part of the environmental and economic solution. It is further believed that integrated resource planning (IRP) processes that consider electric and gas technologies on an equal footing would come to the same conclusion for many regions of the United States. 9 refs., 3 tabs.

  20. Absorption Heat Pumping- Have You Tried It? 

    E-Print Network [OSTI]

    Davis, R. C.

    1985-01-01

    The concept of a thermal powered absorption heat pump is not a new or revolutionary idea. It has been successfully demonstrated in the lab and prototypes have been installed in the field. Units have been successfully applied in a number...

  1. Structure and Fine Structure in Multiparticle Production Data at High Energies

    E-Print Network [OSTI]

    Wit Busza

    2004-10-22

    A summary is given of data on the longitudinal rapidity and pseudorapidity distributions observed in $e^+e^-$, pp, pA and AA collisions at high energies. The remarkable simplicity and universality observed in the data and its relevance to the study of the high energy density system produced in heavy ion collisions is discussed.

  2. Regional respiratory tract absorption of inhaled reactive gases

    SciTech Connect (OSTI)

    Miller, F.J.; Overton, J.H.; Kimbell, J.S.; Russell, M.L.

    1992-06-29

    Highly reactive gases present unique problems due to the number of factors which must be taken into account to determine regional respiratory tract uptake. The authors reviewed some of the physical, chemical, and biological factors that affect dose and that must be understood to interpret toxicological data, to evaluate experimental dosimetry studies, and to develop dosimetry models. Selected dosimetry experiments involving laboratory animals and humans were discussed, showing the variability and uptake according to animal species and respiratory tract region for various reactive gases. New experimental dosimetry approaches, such as those involving isotope ratio mass spectroscopy and cyclotron generation reactive gases, were discussed that offer great promise for improving the ability to study regional respiratory tract absorption of reactive gases. Various dosimetry modeling applications were discussed which demonstrate: the importance of airflow patterns for site-specific dosimetry in the upper respiratory tract, the influence of the anatomical model used to make inter- and intraspecies dosimetric comparisons, the influence of tracheobronchial path length on predicted dose curves, and the implications of ventilatory unit structure and volume on dosimetry and response. Collectively, these examples illustrate important aspects of regional respiratory tract absorption of inhaled reactive gases. Given the complex nature of extent and pattern of injury in the respiratory tract from exposure to reactive gases, understanding interspecies differences in the absorption of reactive gases will continue to be an important area for study.

  3. DNA Concentration By UV Spectrophotometry Measure Absorption

    E-Print Network [OSTI]

    Aris, John P.

    DNA Concentration By UV Spectrophotometry Measure Absorption: 1. Dilute DNA to 0.5 to 50 µg/ml in TE buffer or dH2O. Plan to use a quartz cuvette or a UV-transparent plastic (disposable) cuvette (1 2. Measure absorption at 260 nm (A260). Start by zeroing instrument with TE buffer or dH2O alone

  4. Spectroscopic study of low-temperature hydrogen absorption in...

    Office of Scientific and Technical Information (OSTI)

    Spectroscopic study of low-temperature hydrogen absorption in palladium Citation Details In-Document Search Title: Spectroscopic study of low-temperature hydrogen absorption in...

  5. Effects of hydrogen/deuterium absorption on the magnetic properties...

    Office of Scientific and Technical Information (OSTI)

    Effects of hydrogendeuterium absorption on the magnetic properties of CoPd multilayers Citation Details In-Document Search Title: Effects of hydrogendeuterium absorption on the...

  6. IHT: Tools for Computing Insolation Absorption by Particle Laden Flows

    SciTech Connect (OSTI)

    Grout, R. W.

    2013-10-01

    This report describes IHT, a toolkit for computing radiative heat exchange between particles. Well suited for insolation absorption computations, it is also has potential applications in combustion (sooting flames), biomass gasification processes and similar processes. The algorithm is based on the 'Photon Monte Carlo' approach and implemented in a library that can be interfaced with a variety of computational fluid dynamics codes to analyze radiative heat transfer in particle-laden flows. The emphasis in this report is on the data structures and organization of IHT for developers seeking to use the IHT toolkit to add Photon Monte Carlo capabilities to their own codes.

  7. CO2 enrichment increases carbon and nitrogen input from fine roots in a deciduous forestinput from fine roots in a deciduous forest

    E-Print Network [OSTI]

    Post, Wilfred M.

    CO2 enrichment increases carbon and nitrogen input from fine roots in a deciduous forestinput from fine roots in a deciduous forest · We assessed the effect of elevated [CO2] Contact: Richard J. Norby Research We assessed the effect of elevated [CO2] on production and mortality of short-lived fine

  8. Measuring optical absorption coefficient of pure water in UV using the integrating cavity absorption meter. 

    E-Print Network [OSTI]

    Wang, Ling

    2008-10-10

    that have been used for absorption in the visible and UV regions. 7 The most intuitive technique to measure absorption of water is the conventional transmission type measurement. Hulburt et. al. used a long path length tube of distilled pure water... deflection spectroscopy [26]. Because the optical absorption of water in the visible and UV regions is very low (less than 0.01 m-1 at its minimum), accurate measurements are difficult. Careful examination of measurement results shows...

  9. Development of fine-resolution analyses and expanded large-scale forcing properties. Part I: Methodology and evaluation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, Zhijin [California Inst. of Technology (CalTech), Pasadena, CA (United States); Univ. of California at Los Angeles, Los Angeles, CA (United States); Vogelmann, Andrew M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Feng, Sha [Univ. of California at Los Angeles, Los Angeles, CA (United States); California Inst. of Technology (CalTech), Pasadena, CA (United States); Liu, Yangang [Brookhaven National Lab. (BNL), Upton, NY (United States); Lin, Wuyin [Brookhaven National Lab. (BNL), Upton, NY (United States); Zhang, Minghua [Stony Brook Univ., NY (United States); Toto, Tami [Brookhaven National Lab. (BNL), Upton, NY (United States); Endo, Satoshi [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-01-27

    We produce fine-resolution, three-dimensional fields of meteorological and other variables for the U.S. Department of Energy’s Atmospheric Radiation Measurement (ARM) Southern Great Plains site. The Community Gridpoint Statistical Interpolation system is implemented in a multiscale data assimilation (MS-DA) framework that is used within the Weather Research and Forecasting model at a cloud-resolving resolution of 2 km. The MS-DA algorithm uses existing reanalysis products and constrains fine-scale atmospheric properties by assimilating high-resolution observations. A set of experiments show that the data assimilation analysis realistically reproduces the intensity, structure, and time evolution of clouds and precipitation associated with a mesoscale convective system. Evaluations also show that the large-scale forcing derived from the fine-resolution analysis has an overall accuracy comparable to the existing ARM operational product. For enhanced applications, the fine-resolution fields are used to characterize the contribution of subgrid variability to the large-scale forcing and to derive hydrometeor forcing, which are presented in companion papers.

  10. Development of fine-resolution analyses and expanded large-scale forcing properties. Part I: Methodology and evaluation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, Zhijin; Vogelmann, Andrew M.; Feng, Sha; Liu, Yangang; Lin, Wuyin; Zhang, Minghua; Toto, Tami; Endo, Satoshi

    2015-01-20

    We produce fine-resolution, three-dimensional fields of meteorological and other variables for the U.S. Department of Energy’s Atmospheric Radiation Measurement (ARM) Southern Great Plains site. The Community Gridpoint Statistical Interpolation system is implemented in a multiscale data assimilation (MS-DA) framework that is used within the Weather Research and Forecasting model at a cloud-resolving resolution of 2 km. The MS-DA algorithm uses existing reanalysis products and constrains fine-scale atmospheric properties by assimilating high-resolution observations. A set of experiments show that the data assimilation analysis realistically reproduces the intensity, structure, and time evolution of clouds and precipitation associated with a mesoscale convective system.more »Evaluations also show that the large-scale forcing derived from the fine-resolution analysis has an overall accuracy comparable to the existing ARM operational product. For enhanced applications, the fine-resolution fields are used to characterize the contribution of subgrid variability to the large-scale forcing and to derive hydrometeor forcing, which are presented in companion papers.« less

  11. Fine-Grained Multi-Resource Scheduling in Cloud Datacenters

    E-Print Network [OSTI]

    Fu, Xiaoming

    Fine-Grained Multi-Resource Scheduling in Cloud Datacenters Yuan Zhang University of G--Cloud datacenters typically require tenants to spec- ify the resource demands for the virtual machines (VMs. Unfortunately, this leads to low resource utilization of cloud datacenters as tenants are obligated

  12. BFA Handbook THE RuskinSCHOOL OF DRAWING & FINE ART

    E-Print Network [OSTI]

    Oxford, University of

    , giving them a firm understanding of constructing practice and a good grounding in health and safety rulesBFA Handbook 2013-2014 THE RuskinSCHOOL OF DRAWING & FINE ART UNIVERSITY OF OXFORD A working guide to essential facts A set of rules and r An explanation of examination criteria and practice A set of health

  13. Unraveling the Excess Air/Coal Fineness Enigma 

    E-Print Network [OSTI]

    Laspe, C. G.

    1983-01-01

    In the use of powered coal as a boiler fuel, the factors involved in heat loss from unburnt carbon in the ash are but partially understood. More finely pulverized coal particles will result in lower carbon-in-ash losses. On the other hand, the finer...

  14. Fine tuning of graphene-metal adhesion by surface alloying

    E-Print Network [OSTI]

    Alfè, Dario

    Fine tuning of graphene-metal adhesion by surface alloying D. Alfe`1,2 , M. Pozzo1 , E. Miniussi3 route for governing the interaction between graphene and metal through the selective choice characterization of the properties of graphene on a model PtRu surface alloy on Ru(0001), with a concentration

  15. WASHLOAD AND FINE SEDIMENT LOAD By Hyoseop S. Woo,1

    E-Print Network [OSTI]

    Julien, Pierre Y.

    WASHLOAD AND FINE SEDIMENT LOAD By Hyoseop S. Woo,1 Pierre Y. Julien,2 M. ASCE, and Everett V describes it very distinctly. He stated that if the sediment is added to the upstream end of a concrete channel and the channel is swept clean, and the sediment has not left any trace in the channel, its rate

  16. Fine-Grained Power Management Using Process-level Profiling

    E-Print Network [OSTI]

    Shi, Weisong

    . To evaluate energy efficiency, the Green Grid group proposed the definition of power usage effectiveness (PUE1 Fine-Grained Power Management Using Process-level Profiling Hui Chen, Youhuizi Li and Weisong Shi Department of Computer Science Wayne State University {huichen,huizi,weisong}@wayne.edu Abstract--Low-power

  17. MIXTURES OF FINE-GRAINED MINERALS KAOLINITE AND CARBONATE GRAINS

    E-Print Network [OSTI]

    Palomino, Angelica M.

    MIXTURES OF FINE-GRAINED MINERALS À KAOLINITE AND CARBONATE GRAINS ANGELICA M. PALOMINO 1, *, SUSAN, Georgia 30332-0355, USA Abstract--The behavior of mineral mixtures can be significantly different from properties of the individual minerals, and their ensuing effects on interparticle interactions and fabric

  18. COMPUTERIZED BREAST CANCER DIAGNOSIS AND PROGNOSIS FROM FINE NEEDLE ASPIRATES

    E-Print Network [OSTI]

    Street, Nick

    1 COMPUTERIZED BREAST CANCER DIAGNOSIS AND PROGNOSIS FROM FINE NEEDLE ASPIRATES William H. Wolberg methods based on linear programming that were applicable to breast cancer diagnosis and prognostic), and 2) improve breast cancer prognostic estimations. The diagnostic accuracy of FNA to diagnose breast

  19. ROTARY FILTER FINES TESTING FOR SMALL COLUMN ION EXCHANGE

    SciTech Connect (OSTI)

    Herman, D.

    2011-08-03

    SRNL was requested to quantify the amount of 'fines passage' through the 0.5 micron membranes currently used for the rotary microfilter (RMF). Testing was also completed to determine if there is any additional benefit to utilizing a 0.1 micron filter to reduce the amount of fines that could pass through the filter. Quantifying of the amount of fines that passed through the two sets of membranes that were tested was accomplished by analyzing the filtrate by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) for titanium. Even with preparations to isolate the titanium, all samples returned results of less than the instrument's detection limit of 0.184 mg/L. Test results show that the 0.5 micron filters produced a significantly higher flux while showing a negligible difference in filtrate clarity measured by turbidity. The first targeted deployment of the RMF is with the Small Column Ion Exchange (SCIX) at the Savannah River Site (SRS). SCIX uses crystalline silicotitanate (CST) to sorb cesium to decontaminate a clarified salt solution. The passage of fine particles through the filter membranes in sufficient quantities has the potential to impact the downstream facilities. To determine the amount of fines passage, a contract was established with SpinTek Filtration to operate a 3-disk pilot scale unit with prototypic filter disk and various feeds and two different filter disk membranes. SpinTek evaluated a set of the baseline 0.5 micron filter disks as well as a set of 0.1 micron filter disks to determine the amount of fine particles that would pass the membrane and to determine the flux each set produced. The membrane on both disk sets is manufactured by the Pall Corporation (PMM 050). Each set of disks was run with three feed combinations: prototypically ground CST, CST plus monosodium titanate (MST), and CST, MST, plus Sludge Batch 6 (SB6) simulant. Throughout the testing, samples of the filtrate were collected, measured for turbidity, and sent back to SRNL for analysis to quantify the amount of fines that passed through the membrane. It should be noted that even though ground CST was tested, it will be transferred to the Defense Waste Processing Facility (DWPF) feed tank and is not expected to require filtration.

  20. Polytopes and Nuclear Structure

    E-Print Network [OSTI]

    Roger Ellman

    2010-12-11

    While the parameters of atomic nuclei, Z and A, indicate a general structural pattern for the nuclei, their exact masses in their fine differences seem not to exhibit the orderly kind of logical system that systematic and orderly nature must exhibit. Appropriate analysis discloses an orderly structure among all the nuclear types and isotopes. A component of that analysis and logical order is the family of geometric forms called polytopes, in particular the regular polyhedrons.

  1. Neutral hydrogen absorption towards Fast Radio Bursts

    E-Print Network [OSTI]

    Fender, Rob

    2015-01-01

    If Fast Radio Bursts (FRBs) are truly at astronomical, in particular cosmological, distances, they represent one of the most exciting discoveries in astrophysics of the past decade. However, the distance to FRBs has, to date, been estimated purely from their excess dispersion, and has not been corroborated by any independent means. In this paper we discuss the possibility of detecting neutral hydrogen absorption against FRBs both from spiral arms within our own galaxy, or from intervening extragalactic HI clouds. In either case a firm lower limit on the distance to the FRB would be established. Absorption against galactic spiral arms may already be detectable for bright low-latitude bursts with existing facilities, and should certainly be so by the Square Kilometre Array (SKA). Absorption against extragalactic HI clouds, which would confirm the cosmological distances of FRBs, should also be detectable with the SKA, and maybe also Arecibo. Quantitatively, we estimate that SKA1-MID should be able to detect extr...

  2. Thermal emission and absorption of radiation in finite inverted-opal photonic crystals

    SciTech Connect (OSTI)

    Florescu, Marian; Stimpson, Andrew J.; Lee, Hwang; Dowling, Jonathan

    2005-09-15

    We study theoretically the optical properties of a finite inverted-opal photonic crystal. The light-matter interaction is strongly affected by the presence of the three-dimensional photonic crystal and the alterations of the light emission and absorption processes can be used to suppress or enhance the thermal emissivity and absorptivity of the dielectric structure. We investigate the influence of the absorption present in the system on the relevant band edge frequencies that control the optical response of the photonic crystal. Our study reveals that the absorption processes cause spectral broadening and shifting of the band edge optical resonances, and determine a strong reduction of the photonic band gap spectral range. Using the angular and spectral dependence of the band edge frequencies for stop bands along different directions, we argue that by matching the blackbody emission spectrum peak with a prescribed maximum of the absorption coefficient, it is possible to achieve an angle-sensitive enhancement of the thermal emission/absorption of radiation. This result opens a way to realize a frequency-sensitive and angle-sensitive photonic crystal absorbers/emitters.

  3. Multi-plasmon absorption in graphene

    E-Print Network [OSTI]

    Marinko Jablan; Darrick E. Chang

    2015-01-21

    We show that graphene possesses a strong nonlinear optical response in the form of multi-plasmon absorption, with exciting implications in classical and quantum nonlinear optics. Specifically, we predict that graphene nano-ribbons can be used as saturable absorbers with low saturation intensity in the far-infrared and terahertz spectrum. Moreover, we predict that two-plasmon absorption and extreme localization of plasmon fields in graphene nano-disks can lead to a plasmon blockade effect, in which a single quantized plasmon strongly suppresses the possibility of exciting a second plasmon.

  4. Corrosion inhibitor for aqueous ammonia absorption system

    DOE Patents [OSTI]

    Phillips, B.A.; Whitlow, E.P.

    1998-09-22

    A method is described for inhibiting corrosion and the formation of hydrogen and thus improving absorption in an ammonia/water absorption refrigeration, air conditioning or heat pump system by maintaining the hydroxyl ion concentration of the aqueous ammonia working fluid within a selected range under anaerobic conditions at temperatures up to 425 F. This hydroxyl ion concentration is maintained by introducing to the aqueous ammonia working fluid an inhibitor in an amount effective to produce a hydroxyl ion concentration corresponding to a normality of the inhibitor relative to the water content ranging from about 0.015 N to about 0.2 N at 25 C. Also, working fluids for inhibiting the corrosion of carbon steel and resulting hydrogen formation and improving absorption in an ammonia/water absorption system under anaerobic conditions at up to 425 F. The working fluids may be aqueous solutions of ammonia and a strong base or aqueous solutions of ammonia, a strong base, and a specified buffer. 5 figs.

  5. Coupled dual loop absorption heat pump

    DOE Patents [OSTI]

    Sarkisian, Paul H. (Watertown, MA); Reimann, Robert C. (Lafayette, NY); Biermann, Wendell J. (Fayetteville, NY)

    1985-01-01

    A coupled dual loop absorption system which utilizes two separate complete loops. Each individual loop operates at three temperatures and two pressures. This low temperature loop absorber and condenser are thermally coupled to the high temperature loop evaporator, and the high temperature loop condenser and absorber are thermally coupled to the low temperature generator.

  6. Corrosion inhibitor for aqueous ammonia absorption system

    DOE Patents [OSTI]

    Phillips, Benjamin A. (Benton Harbor, MI); Whitlow, Eugene P. (St. Joseph, MI)

    1998-09-22

    A method of inhibiting corrosion and the formation of hydrogen and thus improving absorption in an ammonia/water absorption refrigeration, air conditioning or heat pump system by maintaining the hydroxyl ion concentration of the aqueous ammonia working fluid within a selected range under anaerobic conditions at temperatures up to 425.degree. F. This hydroxyl ion concentration is maintained by introducing to the aqueous ammonia working fluid an inhibitor in an amount effective to produce a hydroxyl ion concentration corresponding to a normality of the inhibitor relative to the water content ranging from about 0.015 N to about 0.2 N at 25.degree. C. Also, working fluids for inhibiting the corrosion of carbon steel and resulting hydrogen formation and improving absorption in an ammonia/water absorption system under anaerobic conditions at up to 425.degree. F. The working fluids may be aqueous solutions of ammonia and a strong base or aqueous solutions of ammonia, a strong base, and a specified buffer.

  7. ABSORPTION HEAT PUMP IN THE DISTRICT HEATING

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    #12;ABSORPTION HEAT PUMP IN THE DISTRICT HEATING PLANT Dr.sc.ing. Agnese Lickrastina M.Sc. Normunds European Heat Pump Summit 2013, Nuremberg, 15-16.10.2013 · Riga District Heating company · Operation of the DH plant Imanta · Selection of the heat pump/chiller · Operation of the heat pump/chiller · Summary

  8. Polymer microcantilevers fabricated via multiphoton absorption polymerization

    E-Print Network [OSTI]

    Teich, Malvin C.

    Polymer microcantilevers fabricated via multiphoton absorption polymerization Z. Bayindir, Y. Sun polymer cantilevers. Atomic force microscopy has been used to characterize the mechanical properties orders of magnitude smaller than would be predicted from the properties of the bulk polymer.6 If correct

  9. Absorption of solar radiation by solar neutrinos

    E-Print Network [OSTI]

    G. Duplancic; P. Minkowski; J. Trampetic

    2004-03-22

    We calculate the absorption probability of photons radiated from the surface of the Sun by a left-handed neutrino with definite mass and a typical momentum for which we choose |p_1|=0.2 MeV, producing a heavier right-handed antineutrino. Considering two transitions the \

  10. Fine-grained hodoscopes based on scintillating optical fibers

    SciTech Connect (OSTI)

    Borenstein, S.R.; Strand, R.C.

    1981-01-01

    In order to exploit the high event rates at ISABELLE, it will be necessary to have fast detection with fine spatial resolution. The authors are currently constructing a prototype fine-grained hodoscope, the elements of which are scintillating optical fibers. The fibers have been drawn from commercially available plastic scintillator which has been clad with a thin layer of silicone. So far it has been demonstrated with one mm diameter fibers, that with a photodetector at each end, the fibers are more than 99% efficient for lengths of about 60 cm. The readout will be accomplished either with small diameter photomultiplier tubes or avalanche photodiodes used either in the linear or Geiger mode. The program of fiber development and evaluation is described. The status of the APD as a readout element is discussed, and an optical encoding readout scheme is described for events of low multiplicity.

  11. Maintenance is the cheapest way to improve fine coal dewatering

    SciTech Connect (OSTI)

    Burger, J.

    1986-01-01

    There are a great many things that a preparation plant operator can do right now to increase fine coal dewatering effectiveness and maintenance is one of them, says Donald A. Dahlstrom, at the University of Utah. Dewatering of fine coal is increasingly important, because electricity generation, the largest coal consumer, is so strongly affected by the moisture content. Every pound of water put into a boiler raises costs about 2 1/2 cents. The heat it takes to turn water to steam and get it out the stack is heat that could have been used to generate power. In addition, there is the cost of shipping the water. You can add the freight costs to that. In contrast it costs about 1/2-cent/lb to remove the water at the preparation plant.

  12. Dissection of a complex disease susceptibility region using a Bayesian stochastic search approach to fine mapping

    E-Print Network [OSTI]

    Wallace, Chris; Cutler, Antony J.; Pontikos, Nikolas; Pekalski, Marcin L.; Burren, Oliver S.; Cooper, Jason D.; García, Arcadio Rubio; Ferreira, Ricardo C.; Guo, Hui; Walker, Neil M.; Smyth, Deborah J.; Rich, Stephen S.; Onengut-Gumuscu, Suna; Sawcer, Stephen J.; Ban, Maria; Richardson, Sylvia; Todd, John A .; Wicker, Linda S.

    2015-01-01

    search algorithm to the fine mapping problem, and demonstrated its improved performance over conventional stepwise and regularised regression through simulation studies. We then applied it to fine map the established multiple sclerosis (MS) and type 1...

  13. Monitoring Fine Sediment; Grande Ronde and John Day Rivers, 1999 Annual Report.

    SciTech Connect (OSTI)

    Rhodes, Jonathan J.; Greene, M. Jonas; Purser, Michael D.

    2000-01-01

    This project was initiated to monitor surface fine sediment levels and overwinter intrusion of fine sediment in spring chinook salmon spawning habitat in the North Folk John Day and Grande Ronde Rivers, for five years.

  14. Carbon dioxide postcombustion capture: a novel screening study of the carbon dioxide absorption performance of 76 amines

    SciTech Connect (OSTI)

    Graeme Puxty; Robert Rowland; Andrew Allport; Qi Yang; Mark Bown; Robert Burns; Marcel Maeder; Moetaz Attalla

    2009-08-15

    The significant and rapid reduction of greenhouse gas emissions is recognized as necessary to mitigate the potential climate effects from global warming. The postcombustion capture (PCC) and storage of carbon dioxide (CO{sub 2}) produced from the use of fossil fuels for electricity generation is a key technology needed to achieve these reductions. The most mature technology for CO{sub 2} capture is reversible chemical absorption into an aqueous amine solution. In this study the results from measurements of the CO{sub 2} absorption capacity of aqueous amine solutions for 76 different amines are presented. Measurements were made using both a novel isothermal gravimetric analysis (IGA) method and a traditional absorption apparatus. Seven amines, consisting of one primary, three secondary, and three tertiary amines, were identified as exhibiting outstanding absorption capacities. Most have a number of structural features in common including steric hindrance and hydroxyl functionality 2 or 3 carbons from the nitrogen. Initial CO{sub 2} absorption rate data from the IGA measurements was also used to indicate relative absorption rates. Most of the outstanding performers in terms of capacity also showed initial absorption rates comparable to the industry standard monoethanolamine (MEA). This indicates, in terms of both absorption capacity and kinetics, that they are promising candidates for further investigation. 30 refs., 8 figs.

  15. Order within disorder: The atomic structure of ion-beam sputtered amorphous tantala (a-Ta?O?)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bassiri, Riccardo; Liou, Franklin; Abernathy, Matthew R.; Lin, Angie C.; Kim, Namjun; Mehta, Apurva; Shyam, Badri; Byer, Robert L.; Gustafson, Eric K.; Hart, Martin; et al

    2015-03-01

    Amorphous tantala (a-Ta?O?) is a technologically important material often used in high-performance coatings. Understanding this material at the atomic level provides a way to further improve performance. This work details extended X-ray absorption fine structure measurements of a-Ta?O? coatings, where high-quality experimental data and theoretical fits have allowed a detailed interpretation of the nearest-neighbor distributions. It was found that the tantalum atom is surrounded by four shells of atoms in sequence; oxygen, tantalum, oxygen, and tantalum. A discussion is also included on how these models can be interpreted within the context of published crystalline Ta?O? and other a-T?O? studies.

  16. Analysis of mesoscopic loss effects in fine layered fluid-saturated ...

    E-Print Network [OSTI]

    santos,,,

    mechanism). These finely layered sediments behave like viscoelastic transversely isotropic (VTI) media at long wavelengths. Analysis of mesoscopic loss effects ...

  17. Three-body abrasive wear of fine pearlite, nanostructured bainite and martensite

    E-Print Network [OSTI]

    Cambridge, University of

    Three-body abrasive wear of fine pearlite, nanostructured bainite and martensite S. Das Bakshi1a steel. The particular steel concerned is a recent innovation capable of generating extremely fine into extremely fine pearlite, nanostructured bainite, and plate martensite. It is found that although the abra

  18. University of South Carolina Proviso 117.79 -Fees and Fines

    E-Print Network [OSTI]

    #12;University of South Carolina Proviso 117.79 - Fees and Fines Authority The University of South Carolina derives its authority to assess various fees and fines in accordance with the South Carolina Code-15 Appropriations Act. Title 34, Chapter 11 of the South Carolina Code of Laws authorizes a fine for returned checks

  19. LI,HOSPEDALES,SONG,GONG: FINE-GRAINED SKETCH-BASED IMAGE RETRIEVAL 1 Fine-Grained Sketch-Based Image Retrieval

    E-Print Network [OSTI]

    Gong, Shaogang

    LI,HOSPEDALES,SONG,GONG: FINE-GRAINED SKETCH-BASED IMAGE RETRIEVAL 1 Fine-Grained Sketch.hospedales@qmul.ac.uk Yi-Zhe Song yizhe.song@qmul.ac.uk Shaogang Gong s.gong@qmul.ac.uk Queen Mary University of London. It may be distributed unchanged freely in print or electronic forms. #12;2 LI,HOSPEDALES,SONG,GONG: FINE

  20. Resonant Soft X-Ray Scattering - Combining Structural with Spectroscop...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    spectroscopy has become an important tool in understanding the electronic structure of materials. Resonant absorption edges in the soft x-ray regime are especially interesting...

  1. Optical absorption in B{sub 13} cluster: A time-dependent density functional approach

    SciTech Connect (OSTI)

    Shinde, Ravindra; Tayade, Meenakshi

    2013-02-05

    The linear optical absorption spectra of three isomers of planar boron cluster B{sub 13} are calculated using time-dependent spin-polarized density functional approach. The geometries of these cluster are optimized at the B3LYP/6-311+G* level of theory. Even though the isomers are almost degenerate, the calculated spectra are quite different, indicating a strong structure-property relationship. Therefore, these computed spectra can be used in the photo-absorption experiments to distinguish between different isomers of a cluster.

  2. Approaching total absorption at near infrared in a large area monolayer graphene by critical coupling

    SciTech Connect (OSTI)

    Liu, Yonghao; Chadha, Arvinder; Zhao, Deyin; Shuai, Yichen; Menon, Laxmy; Yang, Hongjun; Zhou, Weidong; Piper, Jessica R.; Fan, Shanhui; Jia, Yichen; Xia, Fengnian; Ma, Zhenqiang

    2014-11-03

    We demonstrate experimentally close to total absorption in monolayer graphene based on critical coupling with guided resonances in transfer printed photonic crystal Fano resonance filters at near infrared. Measured peak absorptions of 35% and 85% were obtained from cavity coupled monolayer graphene for the structures without and with back reflectors, respectively. These measured values agree very well with the theoretical values predicted with the coupled mode theory based critical coupling design. Such strong light-matter interactions can lead to extremely compact and high performance photonic devices based on large area monolayer graphene and other two–dimensional materials.

  3. Effects of thermal motion on electromagnetically induced absorption

    SciTech Connect (OSTI)

    Tilchin, E.; Wilson-Gordon, A. D.; Firstenberg, O. [Department of Chemistry, Bar-Ilan University, Ramat Gan IL-52900 (Israel); Department of Physics, Technion-Israel Institute of Technology, Haifa IL-32000 (Israel)

    2011-05-15

    We describe the effect of thermal motion and buffer-gas collisions on a four-level closed N system interacting with strong pump(s) and a weak probe. This is the simplest system that experiences electromagnetically induced absorption (EIA) due to transfer of coherence via spontaneous emission from the excited state to the ground state. We investigate the influence of Doppler broadening, velocity-changing collisions (VCC), and phase-changing collisions (PCC) with a buffer gas on the EIA spectrum of optically active atoms. In addition to exact expressions, we present an approximate solution for the probe absorption spectrum, which provides physical insight into the behavior of the EIA peak due to VCC, PCC, and the wave-vector difference between the pump and probe beams. VCC are shown to produce a wide pedestal at the base of the EIA peak, which is scarcely affected by the pump-probe angular deviation, whereas the sharp central EIA peak becomes weaker and broader due to the residual Doppler-Dicke effect. Using diffusionlike equations for the atomic coherences and populations, we construct a spatial-frequency filter for a spatially structured probe beam and show that Ramsey narrowing of the EIA peak is obtained for beams of finite width.

  4. Modeling fine particle (dusty) plasmas and charge-stabilized colloidal suspensions as inhomogeneous Yukawa systems

    E-Print Network [OSTI]

    Totsuji, Hiroo

    2014-01-01

    In order to give a basis to the structure and correlation analysis of fine particle (dusty) plasma and colloidal suspensions, thermodynamic treatment of mixtures of macroscopic and microscopic charged particles within the adiabatic response of the latter is extended to include the case where the system is finite and weakly inhomogeneous. It is shown that the effective potential for macroscopic particles is composed of two elements: mutual Yukawa repulsion and a confining (attractive) Yukawa potential from their `shadow' or the average charge density of macroscopic particles multiplied by the minus sign. The result clarifies the relation between two approaches hitherto taken where either a parabolic one-body potential is assumed or the average distribution is assumed to be flat with finite extension.

  5. Polaron absorption in amorphous tungsten oxide films

    SciTech Connect (OSTI)

    Berggren, Lars; Azens, Andris; Niklasson, Gunnar A.

    2001-08-15

    Amorphous thin films of tungsten oxide were deposited by sputtering onto glass substrates covered by conductive indium--tin oxide. The density and stoichiometry were determined by Rutherford backscattering spectrometry. Lithium ions were intercalated electrochemically into the films. The optical reflectance and transmittance were measured in the wavelength range from 0.3 to 2.5 {mu}m, at a number of intercalation levels. The polaron absorption peak becomes more symmetric and shifts to higher energies until an intercalation level of 0.25 to 0.3 Li{sup +}/W, where a saturation occurs. The shape of the polaron peak is in very good agreement with the theory of Bryksin [Fiz. Tverd. Tela 24, 1110 (1982)]. Within this model, the shift of the absorption peak is interpreted as an increase in the Fermi level of the material as more Li ions are inserted. {copyright} 2001 American Institute of Physics.

  6. Integrated vacuum absorption steam cycle gas separation

    DOE Patents [OSTI]

    Chen, Shiaguo (Champaign, IL); Lu, Yonggi (Urbana, IL); Rostam-Abadi, Massoud (Champaign, IL)

    2011-11-22

    Methods and systems for separating a targeted gas from a gas stream emitted from a power plant. The gas stream is brought into contact with an absorption solution to preferentially absorb the targeted gas to be separated from the gas stream so that an absorbed gas is present within the absorption solution. This provides a gas-rich solution, which is introduced into a stripper. Low pressure exhaust steam from a low pressure steam turbine of the power plant is injected into the stripper with the gas-rich solution. The absorbed gas from the gas-rich solution is stripped in the stripper using the injected low pressure steam to provide a gas stream containing the targeted gas. The stripper is at or near vacuum. Water vapor in a gas stream from the stripper is condensed in a condenser operating at a pressure lower than the stripper to concentrate the targeted gas. Condensed water is separated from the concentrated targeted gas.

  7. Effective Absorption Enhancement in Small Molecule Organic Solar Cells by Employing Trapezoid Gratings

    E-Print Network [OSTI]

    Chun-Ping, Xiang; Yu, Jin; Bin-Zong, Xu; Wei-Min, Wang; Xin, Wei; Guo-Feng, Song; Yun, Xu

    2013-01-01

    We demonstrate the optical absorption has been enhanced in the small molecule organic solar cells by employing trapezoid grating structure. The enhanced absorption is mainly attributed to both waveguide modes and surface plasmon modes, which has been simulated by using finite-difference time-domain method. The simulated results show that the surface plasmon along the semitransparent metallic Ag anode is excited by introducing the periodical trapezoid gratings, which induce high intensity field increment in the donor layer. Meanwhile, the waveguide modes result a high intensity field in acceptor layer. The increment of field improves the absorption of organic solar cells, significantly, which has been demonstrated by simulating the electrical properties. The simulated results exhibiting 31 % increment of the short-circuit current has been achieved in the optimized device, which is supported by the experimental measurement. The power conversion efficiency of the grating sample obtained in experiment exhibits an...

  8. Study of light-induced vector changes in the local atomic structure of AsSe glasses by EXAFS

    E-Print Network [OSTI]

    Drabold, David

    Study of light-induced vector changes in the local atomic structure of As­Se glasses by EXAFS G changes in the local structure of As­Se glasses using extended X-ray ab- sorption fine structure (EXAFS

  9. Radiation absorption properties of different plaster samples

    SciTech Connect (OSTI)

    Akkurt, Iskender; Guenoglu, Kadir; Mavi, Betuel; K Latin-Small-Letter-Dotless-I l Latin-Small-Letter-Dotless-I ncarslan, Semsettin; Seven, Aysun

    2012-09-06

    Although the plaster is one of the oldest known synthetic building materials, nowadays, it is used as interior coating of walls and ceilings of buildings. Thus measuring its radiation shielding properties is vital. For this purpose, radiation absorption properties of different plaster samples in this study. The measurements have been performed using gamma spectrometer system which connected to 3'' Multiplication-Sign 3''NaI (TI) detector.

  10. CO2 Capture by Absorption with Potassium Carbonate

    SciTech Connect (OSTI)

    Gary T. Rochelle; Marcus Hilliard; Eric Chen; Babatunde Oyenekan; Ross Dugas; John McLees; Andrew Sexton; Daniel Ellenberger

    2005-10-26

    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. Modeling of stripper performance suggests that vacuum stripping may be an attractive configuration for all solvents. Flexipac 1Y structured packing performs in the absorber as expected. It provides twice as much mass transfer area as IMTP No.40 dumped packing. Independent measurements of CO{sub 2} solubility give a CO{sub 2} loading that is 20% lower than that Cullinane's values with 3.6 m PZ at 100-120 C. The effective mass transfer coefficient (K{sub G}) in the absorber with 5 m K/2.5 m PZ appears to be 0 to 30% greater than that of 30 wt% MEA.

  11. Tailor the functionalities of metasurfaces: From perfect absorption to phase modulation

    E-Print Network [OSTI]

    Qu, Che; Hao, Jiaming; Qiu, Meng; Li, Xin; Xiao, Shiyi; Miao, Ziqi; Dai, Ning; He, Qiong; Sun, Shulin; Zhou, Lei

    2015-01-01

    Metasurfaces in metal/insulator/metal configuration have recently been widely used in photonics research, with applications ranging from perfect absorption to phase modulation, but why and when such structures can realize what kind of functionalities are not yet fully understood. Here, based on a coupled-mode theory analysis, we establish a complete phase diagram in which the optical properties of such systems are fully controlled by two simple parameters (i.e., the intrinsic and radiation losses), which are in turn dictated by the geometrical/material parameters of the underlying structures. Such a phase diagram can greatly facilitate the design of appropriate metasurfaces with tailored functionalities (e.g., perfect absorption, phase modulator, electric/magnetic reflector, etc.), demonstrated by our experiments and simulations in the Terahertz regime. In particular, our experiments show that, through appropriate structural/material tuning, the device can be switched across the functionality phase boundaries...

  12. Optical hydrogen absorption consistent with a thin bow shock leading the hot Jupiter HD 189733b

    E-Print Network [OSTI]

    Cauley, P Wilson; Jensen, Adam G; Barman, Travis; Endl, Michael; Cochran, William D

    2015-01-01

    Bow shocks are ubiquitous astrophysical phenomena resulting from the supersonic passage of an object through a gas. Recently, pre-transit absorption in UV metal transitions of the hot Jupiter exoplanets HD 189733b and WASP12-b have been interpreted as being caused by material compressed in a planetary bow shock. Here we present a robust detection of a time-resolved pre-transit, as well as in-transit, absorption signature around the hot Jupiter exoplanet HD 189733b using high spectral resolution observations of several hydrogen Balmer lines. The line shape of the pre-transit feature and the shape of the time series absorption provide the strongest constraints on the morphology and physical characteristics of extended structures around an exoplanet. The in-transit measurements confirm the previous exospheric H-alpha detection although the absorption depth measured here is ~50% lower. The pre-transit absorption feature occurs 125 minutes before the predicted optical transit, a projected linear distance from the ...

  13. FineTex EnE Inc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar2-0057-EA Jump to:ofEnia SpA JumpGmbHFerrisFillmore CityGlobal ClimateFineTex

  14. A Computational Model for Sound Field Absorption by Acoustic Arrays

    E-Print Network [OSTI]

    . We then formulate the acoustic wave equation with the absorption boundary coeÆcient in the frequency the sound absorption property of arrays of micro-acoustic actuators at a control surface. We use the waveA Computational Model for Sound Field Absorption by Acoustic Arrays H. T. Banks #3; D. G. Cole z K

  15. Split-flow regeneration in absorptive air separation

    DOE Patents [OSTI]

    Weimer, R.F.

    1987-11-24

    A chemical absorptive separation of air in multiple stage of absorption and desorption is performed with partial recycle of absorbent between stages of desorption necessary to match equilibrium conditions in the various stages of absorption. This allows reduced absorbent flow, reduced energy demand and reduced capital costs. 4 figs.

  16. Chukwuemeka I. Okoye Carbon Dioxide Solubility and Absorption Rate in

    E-Print Network [OSTI]

    Rochelle, Gary T.

    Copyright by Chukwuemeka I. Okoye 2005 #12;Carbon Dioxide Solubility and Absorption Rate _______________________ Nicholas A. Peppas #12;Carbon Dioxide Solubility and Absorption Rate in Monoethanolamine/Piperazine/H2O for. #12;iii Carbon Dioxide Solubility and Absorption Rate in Monoethanolamine/Piperazine/H2O

  17. Quantum of optical absorption in two-dimensional semiconductors

    E-Print Network [OSTI]

    California at Berkeley, University of

    . Absorptance quantization appears to be universal in 2D systems including III­V quantum wells and graphene quantitative examination of the intrinsic absorption properties of free-standing 2D semiconductor thin films work has shown that graphene, a 2D semimetal, has a universal value of light absorption, namely , where

  18. Split-flow regeneration in absorptive air separation

    DOE Patents [OSTI]

    Weimer, Robert F. (Allentown, PA)

    1987-01-01

    A chemical absorptive separation of air in multiple stage of absorption and desorption is performed with partial recycle of absorbent between stages of desorption necessary to match equilibrium conditions in the various stages of absorption. This allows reduced absorbent flow, reduced energy demand and reduced capital costs.

  19. Alvin Fine SA305: Spring 2013 Alvin Fine produces three perfumes from raw material. Thirty thousand ounces of raw material is available. Each

    E-Print Network [OSTI]

    Phillips, David

    Alvin Fine SA305: Spring 2013 Alvin Fine produces three perfumes from raw material. Thirty thousand ounces of raw material is available. Each ounce of raw material can be transformed into 0.4 ounces producing enough perfume. Let R = ounces of raw material bought P1 = ounces of perfume 1 made and sold P1T

  20. Improvement of the Performance for an Absorption Refrigeration System with Lithium bromide-water as Refrigerant by Increasing Absorption Pressure 

    E-Print Network [OSTI]

    Xie, G.; Sheng, G.; Li, G.; Pan, S.

    2006-01-01

    , the low COP of the absorption machine was limited seriously to compete with the refrigeration machine that is drove by electricity. Therefore, most researchers focus their attention on the improvement of performance of the absorption system through many...

  1. Photodetector with absorbing region having resonant periodic absorption between reflectors

    DOE Patents [OSTI]

    Bryan, R.P.; Olbright, G.R.; Brennan, T.M.; Tsao, J.Y.

    1995-02-14

    A photodetector is disclosed that is responsive to a wavelength or wavelengths of interest which have heretofore been unrealized. The photodetector includes a resonant cavity structure bounded by first and second reflectors, the resonant cavity structure being resonant at the wavelength or wavelengths of interest for containing a plurality of standing waves therein. The photodetector further includes a radiation absorbing region disposed within the resonant cavity structure, the radiation absorbing region including a plurality of radiation absorbing layers spaced apart from one another by a distance substantially equal to a distance between antinodes of adjacent ones of the standing waves. Each of radiation absorbing layers is spatially positioned at a location of one of the antinodes of one of the standing waves such that radiation absorption is enhanced. The radiation absorbing layers may be either bulk layers or quantum wells includes a plurality of layers, each of which is comprised of a strained layer of InGaAs. Individual ones of the InGaAs layers are spaced apart from one another by a GaAs barrier layer. 11 figs.

  2. Photodetector with absorbing region having resonant periodic absorption between reflectors

    DOE Patents [OSTI]

    Bryan, Robert P. (Boulder, CO); Olbright, Gregory R. (Boulder, CO); Brennan, Thomas M. (Albuquerque, NM); Tsao, Jeffrey Y. (Albuquerque, NM)

    1995-02-14

    A photodetector that is responsive to a wavelength or wavelengths of interest which have heretofore been unrealized. The photodetector includes a resonant cavity structure bounded by first and second reflectors, the resonant cavity structure being resonant at the wavelength or wavelengths of interest for containing a plurality of standing waves therein. The photodetector further includes a radiation absorbing region disposed within the resonant cavity structure, the radiation absorbing region including a plurality of radiation absorbing layers spaced apart from one another by a distance substantially equal to a distance between antinodes of adjacent ones of the standing waves. Each of radiation absorbing layers is spatially positioned at a location of one of the antinodes of one of the standing waves such that radiation absorption is enhanced. The radiation absorbing layers may be either bulk layers or quantum wells includes a plurality of layers, each of which is comprised of a strained layer of InGaAs. Individual ones of the InGaAs layers are spaced apart from one another by a GaAs barrier layer.

  3. Absorption of solar radiation by the cloudy atmosphere: Further interpretations of collocated aircraft measurements

    E-Print Network [OSTI]

    1999-01-01

    J. Vitko Jr. , Absorption of solar radiation by the cloudyet al. , Absorption of solar radiation by clouds: Observa-1999 Absorption of solar radiation by the cloudy atmosphere:

  4. Rich magneto-absorption spectra in AAB-stacked trilayer graphene

    E-Print Network [OSTI]

    Do, Thi-Nga; Chang, Cheng-Pong; Lin, Chiun-Yan; Lin, Ming-Fa

    2015-01-01

    The generalized tight-binding model is developed to investigate the feature-rich magneto-optical properties of AAB-stacked trilayer graphene. Three intragroup and six intergroup inter-Landau-level (inter-LL) optical excitations largely enrich the magneto-absorption peaks. In general, the former are much higher than the latter, depending on the phases and amplitudes of LL wavefunctions. The absorption spectra exhibit the single- or twin-peak structures which are determined by the quantum modes, LL energy spectra and Fermion distribution. The splitting LLs, with different localization centers (2/6 and 4/6 positions in a unit cell), can generate very distinct absorption spectra. There exist extra single peaks because of LL anticrosings. AAB, AAA, ABA, and ABC stackings quite differ from one another in terms of the inter-LL category, frequency, intensity, and structure of absorption peaks. The main characteristics of LL wavefunctions and energy spectra and the Fermi-Dirac function are responsible for the configur...

  5. Recovery of coal fines from preparation plant effluents

    SciTech Connect (OSTI)

    Choudhry, V. (Praxis Engineers, Inc., Milpitas, CA (USA)); Khan, L. (Illinois State Geological Survey, Champaign, IL (USA)); Yang, D. (Michigan Technological Univ., Houghton, MI (USA))

    1990-01-01

    The objectives of this project are to test and demonstrate the feasibility of recovering the coal fines which are currently disposed of with plant effluent streams in order to produce a fine clean coal product. This product can then be blended with the coarse clean coal from the preparation plant. Recovery of carbonaceous material from the effluent streams will be effected by means of Michigan Technological University's static tube flotation process in conjunction with pyrite depressants. This process has been successfully demonstrated on a number of coals to reject 85% of the pyritic sulfur and recover 90% of the Btu value. The process parameters will be modified to accept preparation plant effluents in order to produce a low-ash, low-sulfur clean coal product that at a minimum is compatible with the quality requirements of the plant clean coal. This report covers the first quarter of the project. The main activities during this period were the drafting of a project work plan and the collection of four coal preparation plant effluent samples for testing. Effluent slurry samples were collected from four operating preparation plants in Illinois and shipped to Michigan Technological University for experimental work.

  6. Effects of rapid thermal annealing on the structural and local atomic properties of ZnO: Ge nanocomposite thin films

    SciTech Connect (OSTI)

    Ceylan, Abdullah Ozcan, Sadan; Rumaiz, Abdul K.; Caliskan, Deniz; Ozbay, Ekmel; Woicik, J. C.

    2015-03-14

    We have investigated the structural and local atomic properties of Ge nanocrystals (Ge-ncs) embedded ZnO (ZnO: Ge) thin films. The films were deposited by sequential sputtering of ZnO and Ge thin film layers on z-cut quartz substrates followed by an ex-situ rapid thermal annealing (RTA) at 600?°C for 30, 60, and 90?s under forming gas atmosphere. Effects of RTA time on the evolution of Ge-ncs were investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM), hard x-ray photoelectron spectroscopy (HAXPES), and extended x-ray absorption fine structure (EXAFS). XRD patterns have clearly shown that fcc diamond phase Ge-ncs of sizes ranging between 18 and 27?nm are formed upon RTA and no Ge-oxide peak has been detected. However, cross-section SEM images have clearly revealed that after RTA process, Ge layers form varying size nanoclusters composed of Ge-ncs regions. EXAFS performed at the Ge K-edge to probe the local atomic structure of the Ge-ncs has revealed that as prepared ZnO:Ge possesses Ge-oxide but subsequent RTA leads to crystalline Ge structure without the oxide layer. In order to study the occupied electronic structure, HAXPES has been utilized. The peak separation between the Zn 2p and Ge 3d shows no significant change due to RTA. This implies little change in the valence band offset due to RTA.

  7. Uniform 2 nm gold nanoparticles supported on iron oxides as active catalysts for CO oxidation reaction: Structure-activity relationship

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Guo, Yu; Senanayake, Sanjaya; Gu, Dong; Jin, Zhao; Du, Pei -Pei; Si, Rui; Xu, Wen -Qian; Huang, Yu -Ying; Tao, Jing; Song, Qi -Sheng; et al

    2015-01-12

    Uniform Au nanoparticles (~2 nm) with narrow size-distribution (standard deviation: 0.5–0.6 nm) supported on both hydroxylated (Fe_OH) and dehydrated iron oxide (Fe_O) have been prepared by either deposition-precipitation (DP) or colloidal-deposition (CD) methods. Different structural and textural characterizations were applied to the dried, calcined and used gold-iron oxide samples. The transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) described the high homogeneity in the supported Au nanoparticles. The ex-situ and in-situ X-ray absorption fine structure (XAFS) characterization monitored the electronic and short-range local structure of active gold species. The synchrotron-based in-situ X-ray diffraction (XRD), together with the corresponding temperature-programmed reductionmore »by hydrogen (H?-TPR), indicated a structural evolution of the iron-oxide supports, correlating to their reducibility. An inverse order of catalytic activity between DP (Au/Fe_OH Au/Fe_O) was observed. Effective gold-support interaction results in a high activity for gold nanoparticles, locally generated by the sintering of dispersed Au atoms on the oxide support in the DP synthesis, while a hydroxylated surface favors the reactivity of externally introduced Au nanoparticles on Fe_OH support for the CD approach. This work reveals why differences in the synthetic protocol translate to differences in the catalytic performance of Au/FeOx catalysts with very similar structural characteristics in CO oxidation.« less

  8. Alternation of the Pd Lattice in Nano-Sized-Pd/ZrO2 Composite during Hydrogen Absorption

    SciTech Connect (OSTI)

    Arachi, Yoshinori; Asai, Takeshi; Emura, Shuichi; Omura, Akira; Nunogaki, Masanobu; Yamaura, Shunichi; Inoue, Akihisa; Arata, Yoshiaki

    2007-02-02

    Structural analysis of high Deuterium absorbed 5 nm Pd particles in dispersed ZrO2 has been carried out using XAFS techniques. X-ray absorption spectra around the Pd K-absorption edge were observed and analyzed. The Pd-Pd bonding distance in the fcc Pd lattice was enlarged by 0.08 {approx} 0.09 A during absorption of deuterium, and it completely reverted to its original state with the release of deuterium while maintaining the crystal lattice symmetry. These changes provide evidence that deuterium locates not on the surface of the Pd particle, but rather within the Pd crystal lattice. XANES spectra clearly indicate that any change in the oxidation state of Pd are not observed, resulting in no reaction of the absorbed Deuterium atoms with Pd atoms. This paper reports the alternation of Pd lattice in nano-sized composite during hydrogen absorption. The possible models of deuterium position in the Pd lattice are also discussed.

  9. 44th Annual Anomalous Absorption Conference

    SciTech Connect (OSTI)

    Beg, Farhat

    2014-03-03

    Conference Grant Report July 14, 2015 Submitted to the U. S. Department of Energy Attn: Dr. Sean Finnegan By the University of California, San Diego 9500 Gilman Drive La Jolla, California 92093 On behalf of the 44th Annual Anomalous Absorption Conference 8-13 June 2014, in Estes Park, Colorado Support Requested: $10,100 Amount expended: $3,216.14 Performance Period: 1 March 20 14 to 28 February 20 15 Principal Investigator Dr. Farhat Beg Center for Energy Research University of California, San Diego 9500 Gilman Drive La Jolla, California 92093-0417 858-822-1266 (telephone) 858-534-4543 (fax) fbeg@ucsd.edu Administrative Point of Contact: Brandi Pate, 858-534-0851, blpate®ucsd.edu I. Background The forty-fourth Anomalous Absorption Conference was held in Estes Park, Colorado from June 5-8, 2014 (aac2014.ucsd.edu). The first Anomalous Absorption Conference was held in 1971 to assemble experts in the poorly understood area of laser-plasma absorption. The goal of that conference was to address the anomalously large laser absorption seen in plasma experiments with respect to the laser absorption predicted by linear plasma theory. Great progress in this research area has been made in the decades since that first meeting, due in part to the scientific interactions that have occurred annually at this conference. Specifically, this includes the development of nonlinear laser-plasma theory and the simulation of laser interactions with plasmas. Each summer since that first meeting, this week-long conference has been held at unique locations in North America as a scientific forum for intense scientific exchanges relevant to the interaction of laser radiation with plasmas. Responsibility for organizing the conference has traditional rotated each year between the major Inertial Confinement Fusion (ICF) laboratories and universities including LANL, LLNL, LLE, UCLA UC Davis and NRL. As the conference has matured over the past four decades, its technical footprint has expanded beyond ICF-related laser-plasma interactions to encompass closely related technical areas including laser particle acceleration, high-intensity laser effects, short­ pulse laser interactions, PIC and Vlasov/rad-hydro modeling, inertial and magnetic fusion plasmas, advanced plasma diagnostics, alternate ignition schemes, EOS/transport/opacity, and this year, x­ ray free-electron lasers and their applications. The conference continues to be a showcase for the presentation and discussion of the latest developments in these areas. II. Meeting Report The conference was extremely successful with more than one hundred participants. There were ninety-nine (99) abstracts submitted. There were forty-four (44) presentations including eleven (11) invited talks. The following topics were covered: a) Radiation Hydrodynamics b) Implosion Plasma Kinetic Effects c) Alternate Ignition Schemes d) Astrophysical Phenomena e) Opacity/Transport/EOS f) High Power Lasers and Facilities g) High-Intensity Laser-Matter Interactions h) Hydrodynamics and Hydro-instabilities i) Hot Dense Plasma Atomic Processes j) High Energy Density Physics k) Laser Particle Acceleration Physics l) Advanced Plasma Diagnostics m) Advanced light sources and applications Despite significant advertising, there were two students who applied for the travel grants: Charlie Jarrott and Joohwan Kim. The total funds expended were $3,216.14.

  10. Distributed Bragg Reflectors With Reduced Optical Absorption

    DOE Patents [OSTI]

    Klem, John F. (Albuquerque, NM)

    2005-08-16

    A new class of distributed Bragg reflectors has been developed. These distributed Bragg reflectors comprise interlayers positioned between sets of high-index and low-index quarter-wave plates. The presence of these interlayers is to reduce photon absorption resulting from spatially indirect photon-assisted electronic transitions between the high-index and low-index quarter wave plates. The distributed Bragg reflectors have applications for use in vertical-cavity surface-emitting lasers for use at 1.55 .mu.m and at other wavelengths of interest.

  11. Absorption Cooling Basics | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i n c i p a l De p u t y A s sconveyance(EPACT 2005) and the EnergyAbsorption

  12. Programmable Differential Delay Circuit With Fine Delay Adjustment

    DOE Patents [OSTI]

    DeRyckere, John F. (Eau Claire, WI); Jenkins, Philip Nord (Eau Claire, WI); Cornett, Frank Nolan (Chippewa Falls, WI)

    2002-07-09

    Circuitry that provides additional delay to early arriving signals such that all data signals arrive at a receiving latch with same path delay. The delay of a forwarded clock reference is also controlled such that the capturing clock edge will be optimally positioned near quadrature (depending on latch setup/hold requirements). The circuitry continuously adapts to data and clock path delay changes and digital filtering of phase measurements reduce errors brought on by jittering data edges. The circuitry utilizes only the minimum amount of delay necessary to achieve objective thereby limiting any unintended jitter. Particularly, this programmable differential delay circuit with fine delay adjustment is designed to allow the skew between ASICS to be minimized. This includes skew between data bits, between data bits and clocks as well as minimizing the overall skew in a channel between ASICS.

  13. Relaxion Cosmology and the Price of Fine-Tuning

    E-Print Network [OSTI]

    Stefano Di Chiara; Kristjan Kannike; Luca Marzola; Antonio Racioppi; Martti Raidal; Christian Spethmann

    2015-11-09

    The relaxion scenario presents an intriguing extension of the standard model in which the particle introduced to solve to the strong CP problem, the axion, also achieves the dynamical relaxation of the Higgs boson mass term. In this work we complete this framework by proposing a scenario of inflationary cosmology that is consistent with all the observational constraints: the relaxion hybrid inflation with an asymmetric waterfall. In our scheme, the vacuum energy of the inflaton drives inflation in a natural way while the relaxion slow-rolls. The constraints on the present inflationary observables are then matched through a subsequent inflationary epoch driven by the inflaton. We quantify the amount of fine-tuning of the proposed inflation scenario, concluding that the inflaton sector severely decreases the naturalness of the theory.

  14. DEVELOPMENT OF A NOVEL FINE COAL CLEANING SYSTEM

    SciTech Connect (OSTI)

    Manoj K. Mohanty

    2005-06-01

    The goal of the proposed project was to develop a novel fine coal separator having the ability to clean 1 mm x 0 size coal in a single processing unit. The novel fine coal separator, named as EG(Enhanced Gravity) Float Cell, utilizes a centrifugal field to clean 1 mm x 250 micron size coal, whereas a flotation environment to clean minus 250 micron coal size fraction. Unlike a conventional enhanced gravity concentrator, which rotates to produce a centrifugal field requiring more energy, the EG Float Cell is fed with a tangential feed slurry to generate an enhanced gravity field without any rotating part. A prototype EG Float Cell unit having a maximum diameter of 60 cm (24 inch) was fabricated during the first-half of the project period followed by a series of exploratory tests to make suitable design modification. Test data indicated that there was a significant concentration of coarse heavy materials in the coarse tailings discharge of the EG Float Cell. The increase in weight (%) of 1 mm x 250 micron (16 x 60 mesh) size fraction from 48.9% in the feed to 72.2% in the coarse tailings discharge and the corresponding increase in the ash content from 56.9% to 87.0% is indicative of the effectiveness of the enhanced gravity section of the EG Float Cell. However, the performance of the flotation section needs to be improved. Some of the possible design modifications may include more effective air sparging system for the flotation section to produce finer bubbles and a better wash water distributor.

  15. (Recovery of coal fines from preparation plant effluents)

    SciTech Connect (OSTI)

    Choudhry, V. (Praxis Engineers, Inc., Milpitas, CA (USA)); Khan, L. (Illinois State Geological Survey, Champaign, IL (USA)); Yang, D. (Michigan Technological Univ., Houghton, MI (USA))

    1991-01-01

    The objectives of this project are to test and demonstrate the feasibility of recovering coal fines which are currently disposed of with plant effluent streams, in order to produce a fine clean coal product. This product can then be blended with the coarse clean coal from the preparation plant. Recovery of coal from the effluent stream samples will be effected by means of Michigan Technological University's static tube flotation process. This process has been successfully demonstrated on a number of raw coals to reject 85% of the pyritic sulfur and recover 90% of the combustible matter. The process parameters will be modified so that this technology can be applied to preparation plant effluents in order to recover a low-ash, low-sulfur clean coal that is, at a minimum, compatible with the quality of the clean coal currently produced from the preparation plant. The main activities during this period were setting up the static tube test unit to conduct the experimental work as outlined in the project work plan. The first of four effluent slurry samples collected from four operating Illinois preparation plants was tested at Michigan Technological University. The first batch of tests resulted in a clean coal containing 7.5% ash at 94.5% combustible matter recovery. Another test aimed at lowering the ash further analyzed at 3.0% ash and 0.92% total sulfur. In addition, analyses of particle size distribution and sink-float testing of the +200 mesh material were undertaken as a part of the effluent characterization work. 5 tabs.

  16. Stabilizing soft fine-grained soils with fly ash

    SciTech Connect (OSTI)

    Edil, T.B.; Acosta, H.A.; Benson, C.H.

    2006-03-15

    The objective of this study was to evaluate the effectiveness of self-cementing fly ashes derived from combustion of subbituminous coal at electric power plants for stabilization of soft fine-grained soils. California bearing ratio (CBR) and resilient modulus (M{sub r}) tests were conducted on mixtures prepared with seven soft fine-grained soils (six inorganic soils and one organic soil) and four fly ashes. The soils were selected to represent a relatively broad range of plasticity, with plasticity indices ranging between 15 and 38. Two of the fly ashes are high quality Class C ashes (per ASTM C 618) that are normally used in Portland cement concrete. The other ashes are off-specification ashes, meaning they do not meet the Class C or Class F criteria in ASTM C 618. Tests were conducted on soils and soil-fly ash mixtures prepared at optimum water content (a standardized condition), 7% wet of optimum water content (representative of the typical in situ condition in Wisconsin), and 9-18% wet of optimum water content (representative of a very wet in situ condition). Addition of fly ash resulted in appreciable increases in the CBR and M{sub r} of the inorganic soils. For water contents 7% wet of optimum, CBRs of the soils alone ranged between 1 and 5. Addition of 10% fly ash resulted in CBRs ranging between 8 and 17, and 18% fly ash resulted in CBRs between 15 and 31. Similarly, M{sub r} of the soil alone ranged between 3 and 15 MPa at 7% wet of optimum, whereas addition of 10% fly ash resulted in M{sub r} between 12 and 60 MPa and 18% fly ash resulted in M{sub r} between 51 and 106 MPa. In contrast, except for one fly ash, addition of fly ash generally had little effect on CBR or M{sub r} of the organic soil.

  17. A strategy to stabilise the local structure of Ti{sup 4+} and Zn{sup 2+} species against aging in TiO{sub 2}/aluminium-doped ZnO bi-layers for applications in hybrid solar cells

    SciTech Connect (OSTI)

    Pellegrino, Giovanna; La Magna, Antonino; Bongiorno, Corrado; Smecca, Emanuele; Alberti, Alessandra, E-mail: alessandra.alberti@imm.cnr.it [CNR-IMM Zona Industriale VIII Strada 5, 95121 Catania (Italy); Condorelli, Guglielmo G. [Università degli studi di Catania and INSTM UdR Catania V.le A. Doria 6, Catania (Italy); Mocuta, Cristian [Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin BP 48, 91192, Gif-sur-Yvette Cedex (France)

    2014-08-07

    We explore a strategy to counteract aging issues in TiO{sub 2}/aluminium-doped ZnO bi-layers used in hybrid solar cells photo-anodes, mainly related to Zn diffusion in the TiO{sub 2} matrix. Different Ti{sup 4+} and Zn{sup 2+} local structures within the anatase grains and along the film thickness were found as a function of post-deposition annealing treatments in the range between 200?°C and 500?°C by synchrotron radiation extended x-ray absorption fine structure analyses. In particular, in the 500?°C-treated sample, diffusion of zinc species along the TiO{sub 2} grain-boundaries has been observed with aging (3?years). In contrast, a mild thermal budget at 200?°C favours a proper atomic arrangement of the zinc-containing anatase lattice which reduces Zn diffusion, thus guaranteeing a good stability with aging.

  18. The Fine Art of the Art Crate: The Protection of Aura

    E-Print Network [OSTI]

    Enos, Joey

    2013-01-01

    Joey Enos The Fine Art ofthe Art Crate The Protection of Aura Waiting after hours onarrival of a crated piece of art for overnight storage. The

  19. Fine-tuning robot-assisted radical prostatectomy planning with MRI

    E-Print Network [OSTI]

    2013-01-01

    article Fine—tuning robot-assisted radical prostatectomyimaging in performing robot—assisted laparoscopic radicalleakage rates after robot—assisted radical prostatectomy.

  20. Matrix elements of heavy-light mesons from a fine lattice

    E-Print Network [OSTI]

    A. Ali Khan; A. Al-Haydari; V. Braun; S. Collins; M. Goeckeler; G. N. Lacagnina; M. Panero; A. Schaefer; G. Schierholz

    2009-01-07

    Results on semileptonic decay matrix elements of heavy-light mesons and charmonium spectrum and decay constant using a fine quenched lattice are presented.

  1. Waste Coal Fines Reburn for NOx and Mercury Emission Reduction

    SciTech Connect (OSTI)

    Stephen Johnson; Chetan Chothani; Bernard Breen

    2008-04-30

    Injection of coal-water slurries (CWS) made with both waste coal and bituminous coal was tested for enhanced reduction of NO{sub x} and Hg emissions at the AES Beaver Valley plant near Monaca, PA. Under this project, Breen Energy Solutions (BES) conducted field experiments on the these emission reduction technologies by mixing coal fines and/or pulverized coal, urea and water to form slurry, then injecting the slurry in the upper furnace region of a coal-fired boiler. The main focus of this project was use of waste coal fines as the carbon source; however, testing was also conducted using pulverized coal in conjunction with or instead of waste coal fines for conversion efficiency and economic comparisons. The host site for this research and development project was Unit No.2 at AES Beaver Valley cogeneration station. Unit No.2 is a 35 MW Babcock & Wilcox (B&W) front-wall fired boiler that burns eastern bituminous coal. It has low NO{sub x} burners, overfire air ports and a urea-based selective non-catalytic reduction (SNCR) system for NO{sub x} control. The back-end clean-up system includes a rotating mechanical ash particulate removal and electrostatic precipitator (ESP) and wet flue gas desulfurization (FGD) scrubber. Coal slurry injection was expected to help reduce NOx emissions in two ways: (1) Via fuel-lean reburning when the slurry is injected above the combustion zone. (2) Via enhanced SNCR reduction when urea is incorporated into the slurry. The mercury control process under research uses carbon/water slurry injection to produce reactive carbon in-situ in the upper furnace, promoting the oxidation of elemental mercury in flue gas from coal-fired power boilers. By controlling the water content of the slurry below the stoichiometric requirement for complete gasification, water activated carbon (WAC) can be generated in-situ in the upper furnace. As little as 1-2% coal/water slurry (heat input basis) can be injected and generate sufficient WAC for mercury capture. During July, August, and September 2007, BES designed, procured, installed, and tested the slurry injection system at Beaver Valley. Slurry production was performed by Penn State University using equipment that was moved from campus to the Beaver Valley site. Waste coal fines were procured from Headwaters Inc. and transported to the site in Super Sacks. In addition, bituminous coal was pulverized at Penn State and trucked to the site in 55-gallon drums. This system was operated for three weeks during August and September 2007. NO{sub x} emission data were obtained using the plant CEM system. Hg measurements were taken using EPA Method 30B (Sorbent Trap method) both downstream of the electrostatic precipitator and in the stack. Ohio Lumex Company was on site to provide rapid Hg analysis on the sorbent traps during the tests. Key results from these tests are: (1) Coal Fines reburn alone reduced NO{sub x} emissions by 0-10% with up to 4% heat input from the CWS. However, the NO{sub x} reduction was accompanied by higher CO emissions. The higher CO limited our ability to try higher reburn rates for further NO{sub x} reduction. (2) Coal Fines reburn with Urea (Carbon enhanced SNCR) decreased NO{sub x} emissions by an additional 30% compared to Urea injection only. (3) Coal slurry injection did not change Hg capture across the ESP at full load with an inlet temperature of 400-430 F. The Hg capture in the ESP averaged 40%, with or without slurry injection; low mercury particulate capture is normally expected across a higher temperature ESP because any oxidized mercury is thought to desorb from the particulate at ESP temperatures above 250 F. (4) Coal slurry injection with halogen salts added to the mixing tank increased the Hg capture in the ESP to 60%. This significant incremental mercury reduction is important to improved mercury capture with hot-side ESP operation and wherever hindrance from sulfur oxides limit mercury reduction, because the higher temperature is above sulfur oxide dew point interference.

  2. Time-Resolved Structural Characterization of Formation and Break-up of Rhodium Clusters Supported in Highly Dealuminated Y Zeolite

    SciTech Connect (OSTI)

    Liang, Ann J.; Gates, Bruce C.

    2009-06-12

    Mononuclear rhodium complexes incorporating two ethylene ligands and anchored to dealuminated zeolite Y by two Rh-O bonds were characterized by transient extended X-ray absorption fine structure (EXAFS) spectroscopy and infrared (IR) spectroscopy as they were converted in the presence of H{sub 2}. EXAFS spectra indicate reduction of the rhodium in the complex at 298 K to form rhodium clusters less than 3 {angstrom} in average diameter. Contacting of the resultant clusters with C{sub 2}H{sub 4} led to their oxidative fragmentation, and the process was reversible. When the H{sub 2} treatment was carried out at a higher temperature (373 K), larger clusters formed. The reduction and oxidation of the rhodium were confirmed by X-ray absorption near edge spectra. During the ethylene treatments, ethyl groups formed on the rhodium, as indicated by IR spectra; treatment in H{sub 2} led to hydrogenation of these groups to form ethane, and the ethyl groups are inferred to be intermediates in the catalytic hydrogenation of ethylene. Ethylene in the gas phase helps to stabilize rhodium in the form of mononuclear complexes on the zeolite during catalysis, hindering the cluster formation.

  3. Performance bound for quantum absorption refrigerators

    E-Print Network [OSTI]

    Luis A. Correa; José P. Palao; Gerardo Adesso; Daniel Alonso

    2013-04-29

    An implementation of quantum absorption chillers with three qubits has been recently proposed, that is ideally able to reach the Carnot performance regime. Here we study the working efficiency of such self-contained refrigerators, adopting a consistent treatment of dissipation effects. We demonstrate that the coefficient of performance at maximum cooling power is upper bounded by 3/4 of the Carnot performance. The result is independent of the details of the system and the equilibrium temperatures of the external baths. We provide design prescriptions that saturate the bound in the limit of a large difference between the operating temperatures. Our study suggests that delocalized dissipation, which must be taken into account for a proper modelling of the machine-baths interaction, is a fundamental source of irreversibility which prevents the refrigerator from approaching the Carnot performance arbitrarily closely in practice. The potential role of quantum correlations in the operation of these machines is also investigated.

  4. Counterflow absorber for an absorption refrigeration system

    DOE Patents [OSTI]

    Reimann, Robert C. (Lafayette, NY)

    1984-01-01

    An air-cooled, vertical tube absorber for an absorption refrigeration system is disclosed. Strong absorbent solution is supplied to the top of the absorber and refrigerant vapor is supplied to the bottom of the absorber to create a direct counterflow of refrigerant vapor and absorbent solution in the absorber. The refrigeration system is designed so that the volume flow rate of refrigerant vapor in the tubes of the absorber is sufficient to create a substantially direct counterflow along the entire length of each tube in the absorber. This provides several advantages for the absorber such as higher efficiency and improved heat transfer characteristics, and allows improved purging of non-condensibles from the absorber.

  5. Gas separation using ultrasound and light absorption

    DOE Patents [OSTI]

    Sinha, Dipen N. (Los Alamos, NM)

    2012-07-31

    An apparatus and method for separating a chosen gas from a mixture of gases having no moving parts and utilizing no chemical processing is described. The separation of particulates from fluid carriers thereof has been observed using ultrasound. In a similar manner, molecular species may be separated from carrier species. It is also known that light-induced drift may separate light-absorbing species from carrier species. Therefore, the combination of temporally pulsed absorption of light with ultrasonic concentration is expected to significantly increase the efficiency of separation by ultrasonic concentration alone. Additionally, breaking the spatial symmetry of a cylindrical acoustic concentrator decreases the spatial distribution of the concentrated particles, and increases the concentration efficiency.

  6. Multi-stage quantum absorption heat pumps

    E-Print Network [OSTI]

    Luis A. Correa

    2014-01-16

    It is well known that heat pumps, while being all limited by the same basic thermodynamic laws, may find realization on systems as "small" and "quantum" as a three-level maser. In order to quantitatively assess how the performance of these devices scales with their size, we design generalized $N$-dimensional ideal heat pumps by merging $N-2$ elementary three-level stages. We set them to operate in the absorption chiller mode between given hot and cold baths, and study their maximum achievable cooling power and the corresponding efficiency as a function of $N$. While the efficiency at maximum power is roughly size-independent, the power itself slightly increases with the dimension, quickly saturating to a constant. Thus, interestingly, scaling up autonomous quantum heat pumps does not render a significant enhancement beyond the optimal double-stage configuration.

  7. Commercialization of Industrialized Absorption Heat Pumps in the US 

    E-Print Network [OSTI]

    Pettigrew, M. G.

    1987-01-01

    OF INDUSTRIAL ABSORPTION HEAT PUMPS IN THE US MALCOLM G. PETTIGREW LITWIN ENGINEERS &CONSTRUCTORS, INC. HOUSTON, ABSTRACT The recovery of waste heat through absorption heat pumping is quite appeal ing to U.S. industry. However, although... this technology has been successfully applied in Europe and Japan, a cauti ous atmosphere wi 11 continue to prevail in the U.S. until the first absorption heat pump is built and successfully demonstrates it's viability for industrial applications...

  8. Continuous Light Absorption Photometer (CLAP) Final Campaign Report

    SciTech Connect (OSTI)

    Jefferson, Anne

    2014-05-01

    The Continuous Light Absorption Photometer (CLAP) measures the aerosol absorption of radiation at three visible wavelengths; 461, 522, and 653 nanometers (nm). Data from this measurement is used in radiative forcing calculations, atmospheric heating rates, and as a prediction of the amount of equivalent black carbon in atmospheric aerosol and in models of aerosol semi-direct forcing. Aerosol absorption measurements are essential to modeling the energy balance of the atmosphere.

  9. UV Interstellar Absorption Lines towards the Starburst Dwarf Galaxy NGC 1705

    E-Print Network [OSTI]

    Sahu, M S

    1997-01-01

    Archival Goddard High Resolution Spectrograph low-resolution spectra of NGC 1705, with wavelength ranges 1170.3 to 1461.7 A and 1453.5 to 1740.1 A and a velocity resolution of about 100 km\\s, have been used to derive the velocity structure and equivalent widths of the absorption lines of Si II 1190.42, 1260.42, 1304.37 and 1526.71 A, S II 1253 , Al II 1670.79 Aand Fe II 1608.45 A in this sightline. Three relatively narrow absorption components are seen at LSR velocities --20 km/s, 260 km/sand 540 km/s. Arguments are presented to show these absorption features are interstellar rather than stellar in origin based on a comparison with the C III 1175.7 A absorption feature. We identify the --20 km/s component with Milky Way disk/halo gas and the 260 km/s component with an isolated high-velocity cloud HVC 487. This small HVC is located about 10 degrees from the H I gas which envelops the Magellanic Clouds and the Magellanic Stream (MS). The (Si/H) ratio for this HVC is > 0.6 (Si/H)solar which together with velocit...

  10. Ab initio calculation of the electronic absorption spectrum of liquid water

    SciTech Connect (OSTI)

    Martiniano, Hugo F. M. C.; Galamba, Nuno; Cabral, Benedito J. Costa; Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa; Instituto de Física da Universidade de São Paulo, CP 66318, 05314-970 São Paulo, SP

    2014-04-28

    The electronic absorption spectrum of liquid water was investigated by coupling a one-body energy decomposition scheme to configurations generated by classical and Born-Oppenheimer Molecular Dynamics (BOMD). A Frenkel exciton Hamiltonian formalism was adopted and the excitation energies in the liquid phase were calculated with the equation of motion coupled cluster with single and double excitations method. Molecular dynamics configurations were generated by different approaches. Classical MD were carried out with the TIP4P-Ew and AMOEBA force fields. The BLYP and BLYP-D3 exchange-correlation functionals were used in BOMD. Theoretical and experimental results for the electronic absorption spectrum of liquid water are in good agreement. Emphasis is placed on the relationship between the structure of liquid water predicted by the different models and the electronic absorption spectrum. The theoretical gas to liquid phase blue-shift of the peak positions of the electronic absorption spectrum is in good agreement with experiment. The overall shift is determined by a competition between the O–H stretching of the water monomer in liquid water that leads to a red-shift and polarization effects that induce a blue-shift. The results illustrate the importance of coupling many-body energy decomposition schemes to molecular dynamics configurations to carry out ab initio calculations of the electronic properties in liquid phase.

  11. Absorption of Foliar-Applied Nitrogen by Cotton

    E-Print Network [OSTI]

    Oosterhuis, Derrick M

    2009-01-01

    on the epicuticular wax composition and ultrastructure ofleaf age, epicuticular wax, and nitrogen-15 absorption. Cropleaf cuticle and epicuticular wax as described by Oosterhuis

  12. Measuring fast electron spectra and laser absorption in relativistic...

    Office of Scientific and Technical Information (OSTI)

    Measuring fast electron spectra and laser absorption in relativistic laser-solid interactions using differential bremsstrahlung photon detectors Citation Details In-Document Search...

  13. The Future of Absorption Technology in America: A Critical Look...

    Broader source: Energy.gov (indexed) [DOE]

    Building, Cooling, Heating, and Power (BCHP) and innovation in order to understand the future of absorption technology in America. absorptionfuture.pdf More Documents &...

  14. Size Dependence of Two-Photon Absorption in Semiconductor Quantum...

    Office of Scientific and Technical Information (OSTI)

    absorption spectroscopy by probing the pump-induced bleaching at the first exciton transition energy. was also calculated using a model based on the multiband...

  15. Magnetic cellulose-derivative structures

    DOE Patents [OSTI]

    Walsh, Myles A. (Falmouth, MA); Morris, Robert S. (Fairhaven, MA)

    1986-09-16

    Structures to serve as selective magnetic sorbents are formed by dissolving a cellulose derivative such as cellulose triacetate in a solvent containing magnetic particles. The resulting solution is sprayed as a fine mist into a chamber containing a liquid coagulant such as n-hexane in which the cellulose derivative is insoluble but in which the coagulant is soluble or miscible. On contact with the coagulant, the mist forms free-flowing porous magnetic microspheric structures. These structures act as containers for the ion-selective or organic-selective sorption agent of choice. Some sorbtion agents can be incorporated during the manufacture of the structure.

  16. Magnetic cellulose-derivative structures

    DOE Patents [OSTI]

    Walsh, M.A.; Morris, R.S.

    1986-09-16

    Structures to serve as selective magnetic sorbents are formed by dissolving a cellulose derivative such as cellulose triacetate in a solvent containing magnetic particles. The resulting solution is sprayed as a fine mist into a chamber containing a liquid coagulant such as n-hexane in which the cellulose derivative is insoluble but in which the coagulant is soluble or miscible. On contact with the coagulant, the mist forms free-flowing porous magnetic microspheric structures. These structures act as containers for the ion-selective or organic-selective sorption agent of choice. Some sorption agents can be incorporated during the manufacture of the structure. 3 figs.

  17. Observing heme doming in myoglobin with femtosecond X-ray absorption spectroscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Levantino, M.; Lemke, H. T.; Schirò, G.; Glownia, M.; Cupane, A.; Cammarata, M.

    2015-07-01

    We report time-resolved X-ray absorption measurements after photolysis of carbonmonoxy myoglobin performed at the LCLS X-ray free electron laser with nearly 100 fs (FWHM) time resolution. Data at the Fe K-edge reveal that the photoinduced structural changes at the heme occur in two steps, with a faster (~70 fs) relaxation preceding a slower (~400 fs) one. We tentatively attribute the first relaxation to a structural rearrangement induced by photolysis involving essentially only the heme chromophore and the second relaxation to a residual Fe motion out of the heme plane that is coupled to the displacement of myoglobin F-helix.

  18. Observing heme doming in myoglobin with femtosecond X-ray absorption spectroscopya)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Levantino, M.; Lemke, H. T.; Schirò, G.; Glownia, M.; Cupane, A.; Cammarata, M.

    2015-07-01

    We report time-resolved X-ray absorption measurements after photolysis of carbonmonoxy myoglobin performed at the LCLS X-ray free electron laser with nearly 100 fs (FWHM) time resolution. Data at the Fe K-edge reveal that the photoinduced structural changes at the heme occur in two steps, with a faster (~70 fs) relaxation preceding a slower (~400 fs) one. We tentatively attribute the first relaxation to a structural rearrangement induced by photolysis involving essentially only the heme chromophore and the second relaxation to a residual Fe motion out of the heme plane that is coupled to the displacement of myoglobin F-helix.

  19. Molecular Dynamics modelling of the adhesive interaction between fine F. A. Gilabert

    E-Print Network [OSTI]

    Krivtsov, Anton M.

    Molecular Dynamics modelling of the adhesive interaction between fine particles F. A. Gilabert the frictionless adhesive interaction force between two fine cohesive polymer grains. The model consists of three a higher resolution near the contact area. Secondly, the cohesion strength (i.e., the work of adhesion

  20. COARSE-TO-FINE PEDESTRIAN LOCALIZATION AND SILHOUETTE EXTRACTION FOR THE GAIT CHALLENGE DATA SETS

    E-Print Network [OSTI]

    Plataniotis, Konstantinos N.

    COARSE-TO-FINE PEDESTRIAN LOCALIZATION AND SILHOUETTE EXTRACTION FOR THE GAIT CHALLENGE DATA SETS This paper presents a localized coarse-to-fine algorithm for efficient and accurate pedestrian localization of capture conditions. The pedestrian targets are localized very well and silhouettes ex- tracted resemble

  1. HallPetch Behavior in Ultra-Fine-Grained AISI 301LN Stainless Steel

    E-Print Network [OSTI]

    Ferreira, Paulo J.

    strength of conventional fully annealed AISI 301LN stainless steels. An analysis of the relationshipHall­Petch Behavior in Ultra-Fine-Grained AISI 301LN Stainless Steel S. RAJASEKHARA, P.J. FERREIRA, L.P. KARJALAINEN, and A. KYRO¨ LA¨ INEN An ultra-fine-grained AISI 301LN austenitic stainless steel

  2. Cartilage mechanobiology : the effects of loading on the fine structure and function of chondroitin sulfate glycosaminoglycans

    E-Print Network [OSTI]

    Szafranski, Jon D. (Jon David)

    2005-01-01

    Chondroitin sulfate is a critical component of articular cartilage due to its contribution to the tissue's resistance to compressive deformation. Alterations in the biosynthesis of this molecule over time could impact the ...

  3. Bayesian reconstruction of binary media with unresolved fine-scale spatial structures

    E-Print Network [OSTI]

    Ray, Jaideep

    . A statistical inverse problem is posed to infer the weights of the Karhunen-Lo`eve modes and , which behavior under applied perturbations (e.g., injection of a tracer, transient pumping/injection, etc

  4. Astron. Nachr./AN 32X (200X) X, XXXXXX Penumbral fine structure: Theoretical understanding

    E-Print Network [OSTI]

    Schlichenmaier, Rolf

    -steady states. These states are compared to time-independent solutions of siphon flow models, which have been-independent siphon flow of Meyer & Schmidt (1968), which describes a steady flow along a magnetic arch. It has been

  5. Fine-Scale Spatial Genetic Structure in Perennial Grasses in Three Environments Steven E. Smith,1

    E-Print Network [OSTI]

    Smith, Steven E.

    relacio´n espacial gene´tica entre la poblacio´n de las plantas (la estructura gene´tica espacial) y estructura espacial gene´tica en tres especies de grami´neas en un medio ambiente semia´rido (Arizona, Me

  6. Fine structure spectrography and its application in speech Hilmi R. Dajani,a)

    E-Print Network [OSTI]

    Wong, Willy

    of Electrical and Computer Engineering, University of Toronto, Rosebrugh Building, 4 Taddle Creek Road, Toronto, Ontario M5S 3G9, Canada Received 11 June 2002; accepted 18 January 2005 A filterbank-based algorithm linked to the source-filter model of speech production Rabiner and Schafer, 1978; Pit- ton et al., 1996

  7. Fine-scale Horizontal Structure of Arctic Mixed-Phase Clouds M. Rambukkange1

    E-Print Network [OSTI]

    Brookhaven National Laboratory, 4 CIRES and NOAA-ETL (Corresponding author: J. Verlinde, 502 Walker Building. Above this layer, separated by a strong inversion, was the remnant of a small decaying lee-side low. Figure 1 shows the dry and dew point temperatures and horizontal wind component profiles through

  8. Evidence for fine-scale genetic structure and estuarine colonisation in a potential high gene flow

    E-Print Network [OSTI]

    Jones, Adam

    of Population Genetics, C/O Biotechnology House, Keldnaholt, Reykjavi´k IS-112, Iceland; 3 School of Biology number of eggs and larvae capable of dispersal via passive or active mechanisms over vast distances, thus

  9. Giant Collective Spin-Orbit Field in a Quantum Well: Fine Structure of Spin

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(Journal Article) |productionPatent:CompressionSciTechwithin the vadoseConnect

  10. Fine-pitch semiconductor detector for the FOXSI mission

    E-Print Network [OSTI]

    Ishikawa, Shin-nosuke; Tajima, Hiroyasu; Tanaka, Takaaki; Watanabe, Shin; Odaka, Hirokazu; Fukuyama, Taro; Kokubun, Motohide; Takahashi, Tadayuki; Terada, Yukikatsu; Krucker, Sam; Christe, Steven; McBride, Steve; Glesener, Lindsay

    2015-01-01

    The Focusing Optics X-ray Solar Imager (FOXSI) is a NASA sounding rocket mission which will study particle acceleration and coronal heating on the Sun through high sensitivity observations in the hard X-ray energy band (5-15 keV). Combining high-resolution focusing X-ray optics and fine-pitch imaging sensors, FOXSI will achieve superior sensitivity; two orders of magnitude better than that of the RHESSI satellite. As the focal plane detector, a Double-sided Si Strip Detector (DSSD) with a front-end ASIC (Application Specific Integrated Circuit) will fulfill the scientific requirements of spatial and energy resolution, low energy threshold and time resolution. We have designed and fabricated a DSSD with a thickness of 500 {\\mu}m and a dimension of 9.6 mm x 9.6 mm, containing 128 strips with a pitch of 75 {\\mu}m, which corresponds to 8 arcsec at the focal length of 2 m. We also developed a low-noise ASIC specified to FOXSI. The detector was successfully operated in the laboratory at a temperature of -20 C and w...

  11. Acicular photomultiplier photocathode structure

    DOE Patents [OSTI]

    Craig, Richard A.; Bliss, Mary

    2003-09-30

    A method and apparatus for increasing the quantum efficiency of a photomultiplier tube by providing a photocathode with an increased surface-to-volume ratio. The photocathode includes a transparent substrate, upon one major side of which is formed one or more large aspect-ratio structures, such as needles, cones, fibers, prisms, or pyramids. The large aspect-ratio structures are at least partially composed of a photoelectron emitting material, i.e., a material that emits a photoelectron upon absorption of an optical photon. The large aspect-ratio structures may be substantially composed of the photoelectron emitting material (i.e., formed as such upon the surface of a relatively flat substrate) or be only partially composed of a photoelectron emitting material (i.e., the photoelectron emitting material is coated over large aspect-ratio structures formed from the substrate material itself.) The large aspect-ratio nature of the photocathode surface allows for an effective increase in the thickness of the photocathode relative the absorption of optical photons, thereby increasing the absorption rate of incident photons, without substantially increasing the effective thickness of the photocathode relative the escape incidence of the photoelectrons.

  12. X-RAY ABSORPTION ANALYSIS OF NGC 3516: APPEARANCE OF FAST COMPONENTS WITH INCREASED SOURCE FLUX

    SciTech Connect (OSTI)

    Holczer, Tomer; Behar, Ehud, E-mail: tomer@physics.technion.ac.il, E-mail: behar@physics.technion.ac.il [Department of Physics, Technion, Haifa 32000 (Israel)

    2012-03-01

    By analyzing the X-ray spectra of NGC 3516 from 2001 and 2006 obtained with the HETGS spectrometer on board the Chandra X-ray Observatory, we find that the kinematic structure of the outflow can be well represented by four outflow components intrinsic to NGC 3516: -350 {+-} 100 km s{sup -1}, -1500 {+-} 150 km s{sup -1}, -2600 {+-} 200 km s{sup -1}, and -4000 {+-} 400 km s{sup -1}. A local component at z = 0 could be confused in the spectrum with intrinsic component 3. Components 1 and 2 have a broad range of ionization manifested by absorption from 23 different charge states of Fe. Components 3 and 4 are more highly ionized and show absorption from only nine different charge states of Fe. However, we were able to reconstruct the absorption measure distribution for all four. The total column density of each component is N{sub H} = (1.8 {+-} 0.5) Multiplication-Sign 10{sup 22} cm{sup -2}, (2.5 {+-} 0.3) Multiplication-Sign 10{sup 22} cm{sup -2}, (6.9 {+-} 4.3) Multiplication-Sign 10{sup 22} cm{sup -2}, and (5.4 {+-} 1.2) Multiplication-Sign 10{sup 22} cm{sup -2}, respectively. The fast components 3 and 4 appear only in the high state of 2006 and not in 2001, while the slower components persist during both epochs. On the other hand, there is no significant absorption variability within days during 2001 or 2006. We find that the covering factor plays a minor role for the line absorption.

  13. AEROSOL ABSORPTION IN CLOUDY SCENES USING PASSIVE SATELLITE INSTRUMENTS

    E-Print Network [OSTI]

    Graaf, Martin de

    AEROSOL ABSORPTION IN CLOUDY SCENES USING PASSIVE SATELLITE INSTRUMENTS M. de Graaf, L.G. Tilstra information has become available from active space-based sensors and some dedicated field campaigns on aerosol-absorption, is the Absorbing Aerosol Index (AAI), which can indicate absorbing aerosols overlying clouds. The AAI is available

  14. Laser Locking with Doppler-free Saturated Absorption Spectroscopy

    E-Print Network [OSTI]

    Novikova, Irina

    - 1 - Laser Locking with Doppler-free Saturated Absorption Spectroscopy Paul L. Stubbs, Advisor the frequency of a 795 nm diode laser using a saturated absorption spectroscopy method. Laser locking in AMO physics is done to stabilize the frequency of lasers used in the laboratory in order to make results more

  15. Absorption of Carbon Dioxide in Aqueous Piperazine/Methyldiethanolamine

    E-Print Network [OSTI]

    Rochelle, Gary T.

    Absorption of Carbon Dioxide in Aqueous Piperazine/Methyldiethanolamine Sanjay Bishnoi and Gary T. Rochelle Dept. of Chemical Engineering, The University of Texas at Austin, Austin, TX 78712 ( )Carbon dioxide absorption in 0.6 M piperazine PZ r4 M methyldiethanolamine ( )MDEA was measured in a wetted wall

  16. Pressure Calibration by the Infrared Absorption Spectrum of Mineral Oil

    E-Print Network [OSTI]

    Collins, Gary S.

    Pressure Calibration by the Infrared Absorption Spectrum of Mineral Oil H. Child, Kenyon College effect is seen in the infrared absorption spectrum of mineral oil. The frequency of two peaks increases as pressure is applied to the mineral oil. At a pressure of about 1 kbar (100 MPa), both peaks are distinct

  17. The role of solar absorption in climate and climate change

    E-Print Network [OSTI]

    1 The role of solar absorption in climate and climate change William Collins UC Berkeley · Changes to surface and atmosphere by aerosols · Climate sensitivity to changes in aerosols and CO2 Research Boulder, Colorado, USA #12;2 Prior Research on Absorption and Climate Field Experiments: · Central

  18. CO2 Capture by Absorption with Potassium Carbonate

    E-Print Network [OSTI]

    Rochelle, Gary T.

    CO2 Capture by Absorption with Potassium Carbonate Second Quarterly Report 2006 Quarterly Progress of this work is to improve the process for CO2 capture by alkanolamine absorption/stripping by developing% inlet CO2. A rate-based model demonstrates that the stripper is primarily controlled by liquid film mast

  19. CO2 Capture by Absorption with Potassium Carbonate

    E-Print Network [OSTI]

    Rochelle, Gary T.

    CO2 Capture by Absorption with Potassium Carbonate First Quarterly Report 2007 Quarterly Progress of this work is to improve the process for CO2 capture by alkanolamine absorption/stripping by developing, requires equivalent work of 31.8 kJ/mole CO2 when used with a double matrix stripper and an intercooled

  20. CO2 Capture by Absorption with Potassium Carbonate

    E-Print Network [OSTI]

    Rochelle, Gary T.

    CO2 Capture by Absorption with Potassium Carbonate First Quarterly Report 2006 Quarterly Progress the process for CO2 capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous. Uninhibited 5 m KHCO3/2.5 m PZ corrodes 5 to 6 times faster that 30% MEA with 0.2 mol CO2/mol MEA. #12

  1. CO2 Capture by Absorption with Potassium Carbonate

    E-Print Network [OSTI]

    Rochelle, Gary T.

    CO2 Capture by Absorption with Potassium Carbonate Third Quarterly Report 2006 Quarterly Progress of this work is to improve the process for CO2 capture by alkanolamine absorption/stripping by developing use. Extensive measurements of CO2 solubility in 7 m MEA at 40 and 60o C have confirmed the work

  2. CO2 Capture by Absorption with Potassium Carbonate

    E-Print Network [OSTI]

    Rochelle, Gary T.

    CO2 Capture by Absorption with Potassium Carbonate Fourth Quarterly Report 2006 Quarterly Progress of this work is to improve the process for CO2 capture by alkanolamine absorption/stripping by developing 20% of the power output from a 500 MW power plant with 90% CO2 removal. The stripper rate model shows

  3. Absorption media for irreversibly gettering thionyl chloride

    DOE Patents [OSTI]

    Buffleben, George (Tracy, CA); Goods, Steven H. (Livermore, CA); Shepodd, Timothy (Livermore, CA); Wheeler, David R. (Albuquerque, NM); Whinnery, Jr., LeRoy (Danville, CA)

    2002-01-01

    Thionyl chloride is a hazardous and reactive chemical used as the liquid cathode in commercial primary batteries. Contrary to previous thinking, ASZM-TEDA.RTM. carbon (Calgon Corporation) reversibly absorbs thionyl chloride. Thus, several candidate materials were examined as irreversible getters for thionyl chloride. The capacity, rate and effect of temperature were also explored. A wide variety of likely materials were investigated through screening experiments focusing on the degree of heat generated by the reaction as well as the material absorption capacity and irreversibility, in order to help narrow the group of possible getter choices. More thorough, quantitative measurements were performed on promising materials. The best performing getter was a mixture of ZnO and ASZM-TEDA.RTM. carbon. In this example, the ZnO reacts with thionyl chloride to form ZnCl.sub.2 and SO.sub.2. The SO.sub.2 is then irreversibly gettered by ASZM-TEDA.RTM. carbon. This combination of ZnO and carbon has a high capacity, is irreversible and functions effectively above -20.degree. C.

  4. Cost reduction in absorption chillers: Phase 2

    SciTech Connect (OSTI)

    Leigh, R.W.

    1989-02-01

    A research program at Brookhaven National Laboratory (BNL) has addressed the possibility of dramatically lowering the first costs of absorption chillers through lowered material intensity and the use of lower cost materials, primarily in the heat exchangers which make up the bulk of the operating components of these systems. This must be done while retaining the best performance characteristics available today, a gross design point coefficient of performance (COP) of 1.3 and a net design (seasonal) average COP of 1.0 (0.90) in a directly fired, double effect unit. We have investigated several possible routes to these goals, and here report on these findings, focusing on the areas that appear most promising. The candidate technologies include the use of polymer film heat exchangers in several applications, the use of thin strips of new, corrosion resistant alloys to replace thicker, less impervious metals in applications exposed to gas flames, and copper or cupro-nickel foils in contact with system water. The use of such materials is only possible in the context of new heat exchanger and system designs, which are also discussed. To lend focus, we have concentrated on a directly fired double effect system providing capacity only. If successful, these techniques will also find wide applicability in heat pumps, cogeneration systems, solar cooling, heat recovery and chemical process heat transfer. 46 refs., 24 figs., 22 tabs.

  5. Two Electron Holes in Hematite Facilitate Water Splitting

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    photoanodes in alkaline electrolyte. They recorded near-edge x-ray absorption fine-structure (NEXAFS) spectra under simulated sunlight and in the dark. Under these...

  6. Theory of triplet optical absorption in oligoacenes: From naphthalene to heptacene

    SciTech Connect (OSTI)

    Chakraborty, Himanshu Shukla, Alok

    2014-10-28

    In this paper, we present a detailed theory of the triplet states of oligoacenes containing up to seven rings, i.e., starting from naphthalene all the way up to heptacene. In particular, we present results on the optical absorption from the first triplet excited state 1{sup 3}B{sub 2u}{sup +} of these oligomers, computed using the Pariser-Parr-Pople model Hamiltonian, and a correlated electron approach employing the configuration-interaction methodology at various levels. Excitation energies of various triplets states obtained by our calculations are in good agreement with the experimental results, where available. The computed triplet spectra of oligoacenes exhibits rich structure dominated by two absorption peaks of high intensities, which are well separated in energy, and are caused by photons polarized along the conjugation direction. This prediction of ours can be tested in future experiments performed on oriented samples of oligoacenes.

  7. Structural characterization of amorphized InP: Evidence for chemical disorder

    SciTech Connect (OSTI)

    Glover, C.J.; Ridgway, M.C.; Yu, K.M.; Foran, G.J.; Lee, T.W.; Moon, Y.; Yoon, E.

    1999-03-01

    Extended x-ray absorption fine-structure measurements at the In {ital K} edge of amorphous InP are presented. The presence of chemical disorder in the form of like-atom bonding has been unambiguously demonstrated in stoichiometric InP amorphized by ion implantation. In{endash}In bonding comprised 14{percent}{plus_minus}4{percent} of the In{endash}atom constituent bonds. Also, relative to the crystalline value of four P atoms, an increase in the total In coordination number to 4.16{plus_minus}0.32 atoms was observed for the amorphous phase, as composed of 3.56{plus_minus}0.19; P and 0.60{plus_minus}0.13; In atoms. Experimental results were consistent with recent {ital ab initio} structural calculations and, furthermore, demonstrated that amorphous InP is best described by a Polk-like continuous random network, containing both even- and odd-membered rings. {copyright} {ital 1999 American Institute of Physics.}

  8. Monitoring Fine Sediment; Grande Ronde and John Day Rivers, 2000 Annual Report.

    SciTech Connect (OSTI)

    Rhodes, Jonathan J.; Greene, M. Jonas; Purser, Michael D.

    2001-01-01

    Fine sediment in spawning substrate has a major effect on salmon survival from egg to smolt. Basin-wide restoration plans have established targets for fine sediment levels in spawning habitat. The project was initiated to monitor surface fine sediment levels and overwinter intrusion of fine sediment in spring chinook salmon spawning habitat in the North Fork John Day (NFJDR) and Grande Ronde Rivers, for five years. The project is also investigating the potential relationship between surface fine levels and overwinter sedimentation. It will provide data to assess trends in substrate conditions in monitored reaches and whether trends are consistent with efforts to improve salmon habitat conditions. The data on the magnitude of overwinter sedimentation will also be used to estimate salmon survival from egg to emergence. In Sept. 1998, 1999, and Aug. 2000, sites for monitoring overwinter sedimentation were established in salmon spawning habitat in the upper Grande Ronde River, Catherine Creek (a Grande Ronde tributary), the North Fork John Day River (NFJDR), and Granite Creek (a NFJDR tributary). Surface fine sediment levels were measured in these reaches via the grid method and visually estimated to test the relative accuracy of these two methods. In 1999 and 2000, surface fine sediment was also estimated via pebble counts at selected reaches to allow comparison of results among the methods. Overwintering substrate samples were collected in April 1999 and April-May 2000 to estimate the amount of overwinter sedimentation in clean gravels in spawning habitat. Monitoring methods and locations are described.

  9. Vitrification testing of soil fines from contaminated Hanford 100 Area and 300 Area soils

    SciTech Connect (OSTI)

    Ludowise, J.D.

    1994-05-01

    The suitability of Hanford soil for vitrification is well known and has been demonstrated extensively in other work. The tests reported here were carried out to confirm the applicability of vitrification to the soil fines (a subset of the Hanford soil potentially different in composition from the bulk soil) and to provide data on the performance of actual, vitrified soil fines. It was determined that the soil fines were generally similar in composition to the bulk Hanford soil, although the fraction <0.25 mm in the 100 Area soil sample appears to differ somewhat from the bulk soil composition. The soil fines are readily melted into a homogeneous glass with the simple additions of CaO and/or Na{sub 2}O. The vitrified waste (plus additives) occupies only 60% of the volume of the initial untreated waste. Leach testing has shown the glasses made from the soil fines to be very durable relative to natural and man-made glasses and has demonstrated the ability of the vitrified waste to greatly reduce the release of radionuclides to the environment. Viscosity and electrical conductivity measurements indicate that the soil fines will be readily processable, although with levels of additives slightly greater than used in the radioactive melts. These tests demonstrate the applicability of vitrification to the contaminated soil fines and the exceptional performance of the waste form resulting from the vitrification of contaminated Hanford soils.

  10. Operating System Support for Fine-Grained Task Migration

    SciTech Connect (OSTI)

    Gioiosa, Roberto; Krishnamoorthy, Sriram

    2012-09-19

    With the end of clock scaling and the limited power budget available (20-30MW), future supercomputers will meet exascale performance primarily through a higher level of parallelism. Current operating (OS) and runtime (RT) systems are designed for the classical SMP model and based on the static and coarse-grained process/thread paradigm. They do not provide the required level of flexibility, especially within a single compute node, to meet the requirements imposed by exascale systems in terms of power/energy efficiency, resilience, managing concurrency and performance portability. The high level of concurrency poses new challenges specific to exascale systems that need to be addressed by novel solutions. In particular, requiring the user to manage billions of concurrent threads could easily result in poor data locality, clogged interconnection networks, unchecked propagation of soft errors, and lack of control over power/energy consumption. Equally important, managing such level of concurrency interferes with the user’s focus on the application and the algorithm. We envision that the computation will be encapsulated into fine-grained tasks that can be isolated and protected from the other tasks running in the system. Whenever a task needs to work on some data that is not stored on the local node, the OS/RT allows the task to be migrated to the node that owns the data. Each task is associated with a contained state (set or architectural registers, stack frame, running node, etc.) that describes the progress of the task and that should be moved together with the task’s code. We believe system support for task migration is a fundamental function that can ease the job of tackling several of the exascale challenges.

  11. Molecular shock response of explosives: electronic absorption spectroscopy

    SciTech Connect (OSTI)

    Mcgrne, Shawn D; Moore, David S; Whitley, Von H; Bolme, Cindy A; Eakins, Daniel E

    2009-01-01

    Electronic absorption spectroscopy in the range 400-800 nm was coupled to ultrafast laser generated shocks to begin addressing the question of the extent to which electronic excitations are involved in shock induced reactions. Data are presented on shocked polymethylmethacrylate (PMMA) thin films and single crystal pentaerythritol tetranitrate (PETN). Shocked PMMA exhibited thin film interference effects from the shock front. Shocked PETN exhibited interference from the shock front as well as broadband increased absorption. Relation to shock initiation hypotheses and the need for time dependent absorption data (future experiments) is briefly discussed.

  12. Unveiling the distribution of absorption in the AGN population

    E-Print Network [OSTI]

    Tom Dwelly; Mathew J. Page

    2005-11-15

    We use the very deep XMM-Newton observations in the CDF-S to measure the distribution of absorption in the AGN population. We describe the Monte Carlo method used to unveil the intrinsic properties of the AGN using their multi-band X-ray colours. The measured distribution of AGN in z, L_X and N_H space is compared with the distributions predicted by a number of XLFs and absorption models. In contrast to other studies, we do not find any evidence that the absorption distribution is dependent on redshift or intrinsic luminosity.

  13. Virginia Polytechnic Institute and State University (Virginia Tech) Fine Arts Loan Agreement

    E-Print Network [OSTI]

    Zallen, Richard

    : _________________________________________________________________ Responsible Dept. and person: ______________________________________________________ Title of work and value: ______________________________________Date of work: __________________ Medium objects lent will be insured under the University's fine arts all-risk, wall-to-wall coverage

  14. The contribution of tympanic transmission to fine temporal signal evaluation in an ultrasonic moth

    E-Print Network [OSTI]

    Rodriguez, R. L.; Schul, J.; Cocroft, R. B.; Greenfield, Michael D.

    2005-11-01

    In lesser waxmoths Achroia grisella, pair formation and female mate choice involve very fine discrimination of male ultrasonic signals. Female A. grisella prefer male signals with longer pulses and longer 'asynchrony ...

  15. Automatic fine-tuning and wind simulation at the Offshore Technology Research Center (OTRC) 

    E-Print Network [OSTI]

    Miller, Mark Alan

    1994-01-01

    A method for developing an automatic fine-tuning controller for matching a specification in the frequency domain is developed for the wind simulation equipment at the Offshore Technology Research Center (OTRC). A test signal synthesis method...

  16. Trophic plasticity and fine-grained resource variation in populations of western mosquitofish, Gambusia affinis

    E-Print Network [OSTI]

    DeWitt, Thomas J.

    Trophic plasticity and fine-grained resource variation in populations of western mosquitofish ABSTRACT Hypothesis: Fish will exhibit morphological plasticity in response to how (food type: live vs, population differentiation, resource polymorphism, trophic plasticity. INTRODUCTION Natural environments vary

  17. The consolidation and strength behavior of mechanically compressed fine-grained sediments

    E-Print Network [OSTI]

    Casey, Brendan (Brendan Anthony)

    2014-01-01

    This thesis investigates the consolidation and shear strength behavior of saturated fine-grained sediments over the effective stress range of 0.1 to 100 MPa. The research makes use of samples which are resedimented in the ...

  18. Fractured Processes: Adaptive, Fine-Grained Process Abstractions Thanumalayan Sankaranarayana Pillai

    E-Print Network [OSTI]

    Swift, Michael

    Fractured Processes: Adaptive, Fine-Grained Process Abstractions Thanumalayan Sankaranarayana. Arpaci-Dusseau University of Wisconsin-Madison Abstract. We introduce Fracture, a novel framework that transforms and modernizes the basic process ab- straction. By "fracturing" an application into logical

  19. A Prototype Two-Decade Fully-Coupled Fine-Resolution CCSM Simulation...

    Office of Scientific and Technical Information (OSTI)

    Fine-Resolution CCSM Simulation A fully coupled global simulation using the Community Climate System Model (CCSM) was configured using grid resolutions of 0.1sup o for the ocean...

  20. Fine root dynamics along an elevational gradient in tropical Amazonian and Andean forests

    E-Print Network [OSTI]

    Malhi, Yadvinder

    synchronised to seasonality of solar radiation. Finally, we provide the first insights into root growth-level productivity is limited. To date, studies from only three elevational transects have provided data on fine root

  1. THE UNIVERSITY OF OKLAHOMA WEITZENHOFFER COLLEGE OF FINE ARTS In the OU Arts District!

    E-Print Network [OSTI]

    Oklahoma, University of

    THE UNIVERSITY OF OKLAHOMA WEITZENHOFFER COLLEGE OF FINE ARTS University of Oklahoma (405) 325-5321 sbent@ou.edu University Theatre presents Handel's Alcina (Norman, Okla., Feb. 21, 2014) The University of Oklahoma

  2. Mountain Brook High School Fine Arts Center: Moisture Control Case Study 

    E-Print Network [OSTI]

    Nunnelly, R. M.

    2002-01-01

    Upon returning to school in the fall, significant problems became evident in the Fine Arts Center of Mountain Brook High School, located near Birmingham, Alabama. In the band department, black mold was found on ceiling tiles, marching band uniforms...

  3. Automated Protocol for the Analysis of Dynamic Mechanical Analyzer Date from Fine Aggregate Asphalt Mixes 

    E-Print Network [OSTI]

    Cavalcanti De Sousa, Pedro

    2010-10-12

    Fatigue cracking and moisture damage are two important modes of distresses in asphalt pavements. Recently, the Dynamic Mechanical Analyzer (DMA) was used to characterize fatigue cracking and evaluate the effects of moisture damage on the Fine...

  4. Operation Synopsis of Gas-Fired Double-Effect Absorption Chillers 

    E-Print Network [OSTI]

    Phillips, J.

    1986-01-01

    Absorption refrigeration systems are one of the oldest systems available. The fundamentals of absorption refrigeration were formulated about 1777, and the first successful absorption machine was developed in 1850. The first U.S. patent...

  5. Thermodynamics and reference scale of SU(3) gauge theory from gradient flow on fine lattices

    E-Print Network [OSTI]

    Masakiyo Kitazawa; Masayuki Asakawa; Tetsuo Hatsuda; Takumi Iritani; Etsuko Itou; Hiroshi Suzuki

    2015-11-17

    We study the parametrization of lattice spacing and thermodynamics of SU(3) gauge theory on the basis of the Yang-Mills gradient flow on fine lattices. The lattice spacing of the Wilson gauge action is determined over a wide range $6.3\\le\\beta\\le7.5$ with high accuracy. The measurements of the flow time and lattice spacing dependences of the expectation values of the energy-momentum tensor are performed on fine lattices.

  6. Thermodynamics and reference scale of SU(3) gauge theory from gradient flow on fine lattices

    E-Print Network [OSTI]

    Kitazawa, Masakiyo; Hatsuda, Tetsuo; Iritani, Takumi; Itou, Etsuko; Suzuki, Hiroshi

    2015-01-01

    We study the parametrization of lattice spacing and thermodynamics of SU(3) gauge theory on the basis of the Yang-Mills gradient flow on fine lattices. The lattice spacing of the Wilson gauge action is determined over a wide range $6.3\\le\\beta\\le7.5$ with high accuracy. The measurements of the flow time and lattice spacing dependences of the expectation values of the energy-momentum tensor are performed on fine lattices.

  7. Charge-transfer absorption and emission in polymer: fullerene...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Charge-transfer absorption and emission in polymer: fullerene solar cells April 13, 2010 at 3pm36-428 Koen Vandewal Linkping University vandewal-small abstract: For an efficient...

  8. Standoff alpha radiation detection via excited state absorption of air

    E-Print Network [OSTI]

    Yao, Jimmy; Brenizer, Jack; Hui, Rongqing; Yin, Stuart (Shizhuo)

    2013-06-24

    A standoff alpha radiation detection technique based on the physical mechanism of excited state absorption of air molecules was explored and is presented in this paper. Instead of directly detecting the radiation via measuring the intensity...

  9. Optical control of nuclear resonant absorption: theory and experiment 

    E-Print Network [OSTI]

    Kolesov, Roman L.

    2004-09-30

    Modification of nuclear resonant absorption by means of laser radiation is analyzed both theoretically and experimentally. Theoretical analysis is done on the basis of four-level model of atom. This model includes both ...

  10. Observation of suppressed terahertz absorption in photoexcited graphene

    E-Print Network [OSTI]

    Frenzel, Alex James

    When light is absorbed by a semiconductor, photoexcited charge carriers enhance the absorption of far-infrared radiation due to intraband transitions. We observe the opposite behavior in monolayer graphene, a zero-gap ...

  11. Present and Future Uses of Industrial Absorption Heat Pumps 

    E-Print Network [OSTI]

    Erickson, D. C.; Davidson, W. F.

    1985-01-01

    This paper examines the present and projects the future uses of industrial absorption heat pumping. AHP technology is seen as an increasingly important component of plant and process heat integration for energy conservation. Existing installations...

  12. Onsite Wastewater Treatment Systems: Septic Tank/Soil Absorption Field 

    E-Print Network [OSTI]

    Lesikar, Bruce J.

    2008-10-23

    For septic tank and soil absorption systems to work properly, homeowners must choose the right kind of system for their household size and soil type, and they must maintain them regularly. This publication explains the treatment, design, operation...

  13. Overview of Resources for Geothermal Absorption Cooling for Buildings

    SciTech Connect (OSTI)

    Liu, Xiaobing; Gluesenkamp, Kyle R; Mehdizadeh Momen, Ayyoub

    2015-06-01

    This report summarizes the results of a literature review in three areas: available low-temperature/coproduced geothermal resources in the United States, energy use for space conditioning in commercial buildings, and state of the art of geothermal absorption cooling.

  14. Optical absorption of pure water in the blue and ultraviolet 

    E-Print Network [OSTI]

    Lu, Zheng

    2007-09-17

    The key feature of the Integrating Cavity Absorption Meter (ICAM) is that it produces an isotropic illumination of the liquid sample and thereby dramatically minimizes scattering effects. The ICAM can produce an ...

  15. Absorption Cycle Fundamentals and Applications Guidelines for Distillation Energy Savings 

    E-Print Network [OSTI]

    Erickson, D. C.; Davidson, W. F.

    1984-01-01

    of applications, embody characteristics that inherently make them economic candidates for absorption cycle heat upgrading. Practical applications to current U.S. distillations could save 30 trillion BTU per year, at payback periods ranging from 1 to 3 years. So...

  16. Study of Interstellar Molecular Clouds using Formaldehyde Absorption toward Extragalactic Radio Sources

    E-Print Network [OSTI]

    Araya, E D; Goss, W M; Andreev, N

    2014-01-01

    We present new Very Large Array 6cm H2CO observations toward four extragalactic radio continuum sources (B0212+735, 3C111, NRAO150, BL Lac) to explore the structure of foreground Galactic clouds as revealed by absorption variability. This project adds a new epoch in the monitoring observations of the sources reported by Marscher and collaborators in the mid 1990's. Our new observations confirm the monotonic increase in H$_2$CO absorption strength toward NRAO150. We do not detect significant variability of our 2009 spectra with respect to the 1994 spectra of 3C111, B0212+735 and BL Lac; however we find significant variability of the 3C111 2009 spectrum with respect to archive observations conducted in 1991 and 1992. Our analysis supports that changes in absorption lines could be caused by chemical and/or geometrical gradients in the foreground clouds, and not necessarily by small scale (~10 AU) high density molecular clumps within the clouds.

  17. POC-scale testing of an advanced fine coal dewatering equipment/technique

    SciTech Connect (OSTI)

    Groppo, J.G.; Parekh, B.K. [Univ. of Kentucky, Lexington, KY (United States); Rawls, P. [Department of Energy, Pittsburgh, PA (United States)

    1995-11-01

    Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 {mu}m) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20 percent level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20 percent or lower moisture using either conventional or advanced dewatering techniques. As the contract title suggests, the main focus of the program is on proof-of-concept testing of a dewatering technique for a fine clean coal product. The coal industry is reluctant to use the advanced fine coal recovery technology due to the non-availability of an economical dewatering process. in fact, in a recent survey conducted by U.S. DOE and Battelle, dewatering of fine clean coal was identified as the number one priority for the coal industry. This project will attempt to demonstrate an efficient and economic fine clean coal slurry dewatering process.

  18. Broad Absorption Line Quasar catalogues with Supervised Neural Networks

    E-Print Network [OSTI]

    Simone Scaringi; Christopher E. Cottis; Christian Knigge; Michael R. Goad

    2008-10-24

    We have applied a Learning Vector Quantization (LVQ) algorithm to SDSS DR5 quasar spectra in order to create a large catalogue of broad absorption line quasars (BALQSOs). We first discuss the problems with BALQSO catalogues constructed using the conventional balnicity and/or absorption indices (BI and AI), and then describe the supervised LVQ network we have trained to recognise BALQSOs. The resulting BALQSO catalogue should be substantially more robust and complete than BI- or AI-based ones.

  19. Lyman alpha Absorption Systems and the Intergalactic Medium

    E-Print Network [OSTI]

    George Efstathiou; Joop Schaye; Tom Theuns

    2000-04-10

    The last few years have seen a dramatic improvement in our understanding of the origin of Lyman alpha absorption systems. Hydrodynamic numerical simulations of cold dark matter dominated universes have shown that the many properties of the Lyman alpha absorption systems can be explained by a photoionized, space-filling, intergalactic medium. Lyman alpha lines offer promising probes of the photoionizing background, the amplitude of the mass fluctuations at high redshift and the evolution of the equation of state of the intergalactic medium.

  20. Modelling aging effects on a thermal cycling absorption process column

    SciTech Connect (OSTI)

    Laquerbe, C.; Contreras, S.; Demoment, J.

    2008-07-15

    Palladium coated on alumina is used in hydrogen separation systems operated at CEA/Valduc, and more particularly in Thermal Cycling Absorption Process columns. With such materials, tritium decay is known to induce aging effects which have direct side effects on hydrogen isotopes absorption isotherms. Furthermore in a TCAP column, aging occurs in an heterogeneous way. The possible impacts of these intrinsic material evolutions on the separation performances are investigated here through a numerical approach. (authors)

  1. CO2 Capture by Absorption with Potassium Carbonate

    SciTech Connect (OSTI)

    Gary T. Rochelle; Eric Chen; Babatunde Oyenekan; Andrew Sexton; Jason Davis; Marus Hiilliard; Qing Xu; David Van Wagener; Jorge M. Plaza

    2006-12-31

    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 best solvent and process configuration, matrix with MDEA/PZ, offers 22% and 15% energy savings over the baseline and improved baseline, respectively, with stripping and compression to 10 MPa. The energy requirement for stripping and compression to 10 MPa is about 20% of the power output from a 500 MW power plant with 90% CO{sub 2} removal. The stripper rate model shows that a ''short and fat'' stripper requires 7 to 15% less equivalent work than a ''tall and skinny'' one. The stripper model was validated with data obtained from pilot plant experiments at the University of Texas with 5m K{sup +}/2.5m PZ and 6.4m K{sup +}/1.6m PZ under normal pressure and vacuum conditions using Flexipac AQ Style 20 structured packing. Experiments with oxidative degradation at low gas rates confirm the effects of Cu{sup +2} catalysis; in MEA/PZ solutions more formate and acetate is produced in the presence of Cu{sup +2}. At 150 C, the half life of 30% MEA with 0.4 moles CO{sub 2}/mole amine is about 2 weeks. At 100 C, less than 3% degradation occurred in two weeks. The solubility of potassium sulfate in MEA solution increases significantly with CO{sub 2} loading and decreases with MEA concentration. The base case corrosion rate in 5 M MEA/1,2M PZ is 22 mpy. With 1 wt% heat stable salt, the corrosion rate increases by 50% to 160% in the order: thiosulfate< oxalate

  2. Angular behavior of the absorption limit in thin film silicon solar cells

    E-Print Network [OSTI]

    Naqavi, Ali; Söderström, Karin; Battaglia, Corsin; Paeder, Vincent; Scharf, Toralf; Herzig, Hans Peter; Ballif, Christophe

    2013-01-01

    We investigate the angular behavior of the upper bound of absorption provided by the guided modes in thin film solar cells. We show that the 4n^2 limit can be potentially exceeded in a wide angular and wavelength range using two-dimensional periodic thin film structures. Two models are used to estimate the absorption enhancement; in the first one, we apply the periodicity condition along the thickness of the thin film structure but in the second one, we consider imperfect confinement of the wave to the device. To extract the guided modes, we use an automatized procedure which is established in this work. Through examples, we show that from the optical point of view, thin film structures have a high potential to be improved by changing their shape. Also, we discuss the nature of different optical resonances which can be potentially used to enhance light trapping in the solar cell. We investigate the two different polarization directions for one-dimensional gratings and we show that the transverse magnetic pola...

  3. Use Low-Grade Waste Steam to Power Absorption Chillers, Energy...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    4 Use Low-Grade Waste Steam to Power Absorption Chillers Absorption chillers use heat, instead of mechanical energy, to provide cooling. The mechanical vapor compressor is replaced...

  4. Free Carrier Absorption due to Dislocation Scattering in GaN Quantum Wells

    SciTech Connect (OSTI)

    Vaidya, R. G. [Department of Physics, Karnatak University, Dharwad, Karnataka (India); Department of Physics, Tumkur University, Tumkur, Karnataka, 572102 (India); Sankeshwar, N. S.; Mulimani, B. G. [Department of Physics, Karnatak University, Dharwad, Karnataka (India)

    2011-10-20

    Free carrier absorption (FCA) is studied in quantum well structures assuming electrons to be scattered by dislocations via strain field. Expression for FCA coefficient, {alpha} is obtained assuming radiation field to be polarized along the plane of quantum well. Numerical results of {alpha}, as function of photon frequency, {Omega} and well width, d are presented. Calculations show, FCA to decrease with increase in {Omega} with a kink observed at {Omega} = 7.79x10{sup 13} s{sup -1} indicating onset of inter subband transitions. {alpha} is found to be proportional to d{sup -3} and to increase with increase in dislocation density.

  5. Lithographic dry development using optical absorption

    DOE Patents [OSTI]

    Olynick, Deirdre; Schuck, P. James; Schmidt, Martin

    2013-08-20

    A novel approach to dry development of exposed photo resist is described in which a photo resist layer is exposed to a visible light source in order to remove the resist in the areas of exposure. The class of compounds used as the resist material, under the influence of the light source, undergoes a chemical/structural change such that the modified material becomes volatile and is thus removed from the resist surface. The exposure process is carried out for a time sufficient to ablate the exposed resist layer down to the layer below. A group of compounds found to be useful in this process includes aromatic calixarenes.

  6. SOURCE SIGNATURES OF FINE PARTICULATE MATTER FROM PETROLEUM REFINING AND FUEL USE

    SciTech Connect (OSTI)

    Gerald P. Huffman; Frank E. Huggins; Naresh Shah; Artur Braun; Yuanzhi Chen; J. David Robertson; Joseph Kyger; Adel F. Sarofim; Ronald J. Pugmire; Henk L.C. Meuzelaar; JoAnn Lighty

    2003-07-31

    The molecular structure and microstructure of a suite of fine particulate matter (PM) samples produced by the combustion of residual fuel oil and diesel fuel were investigated by an array of analytical techniques. Some of the more important results are summarized below. Diesel PM (DPM): A small diesel engine test facility was used to generate a suite of diesel PM samples from different fuels under engine load and idle conditions. C XANES, {sup 13}C NMR, XRD, and TGA were in accord that the samples produced under engine load conditions contained more graphitic material than those produced under idle conditions, which contained a larger amount of unburned diesel fuel and lubricating oil. The difference was enhanced by the addition of 5% of oxygenated compounds to the reference fuel. Scanning transmission x-ray micro-spectroscopy (STXM) was able to distinguish particulate regions rich in C=C bonds from regions rich in C-H bonds with a resolution of {approx}50 nm. The former are representative of more graphitic regions and the latter of regions rich in unburned fuel and oil. The dominant microstructure observed by SEM and TEM consisted of complex chain-like structures of PM globules {approx}20-100 nm in mean diameter, with a high fractal dimension. High resolution TEM revealed that the graphitic part of the diesel soot consisted of onion-like structures made up of graphene layers. Typically 3-10 graphene layers make up the ''onion rings'', with the layer spacing decreasing as the number of layers increases. ROFA PM: Residual oil fly ash (ROFA) PM has been analyzed by a new approach that combines XAFS spectroscopy with selective leaching procedures. ROFA PM{sub 2.5} and PM{sub 2.5+} produced in combustion facilities at the U.S. EPA National Risk Management Research Laboratory (NRML) were analyzed by XAFS before and after leaching with water, acid (1N HCl), and pentane. Both water and acid leaching removed most of the metal sulfates, which were the dominant phase present for most metals (V, Ni, Zn, etc.). This allowed conclusive identification in the leaching residue of important secondary sulfide and oxide phases, including Ni sulfide, a toxic and carcinogenic phase observed in the leached PM{sub 2.5+} samples. Other significant secondary phases identified included V{sub 2}O{sub 4}, V sulfide, and NiFe{sub 2}O{sub 4}.

  7. Local structure in solid solutions of stabilised zirconia with actinide dioxides (UO{sub 2}, NpO{sub 2})

    SciTech Connect (OSTI)

    Walter, Marcus; Somers, Joseph; Bouexiere, Daniel; Rothe, Joerg

    2011-04-15

    The local structure of (Zr,Lu,U)O{sub 2-x} and (Zr,Y,Np)O{sub 2-x} solid solutions has been investigated by extended X-ray absorption fine structure (EXAFS). Samples were prepared by mixing reactive (Zr,Lu)O{sub 2-x} and (Zr,Y)O{sub 2-x} precursor materials with the actinide oxide powders, respectively. Sintering at 1600 {sup o}C in Ar/H{sub 2} yields a fluorite structure with U(IV) and Np(IV). As typical for stabilised zirconia the metal-oxygen and metal-metal distances are characteristic for the different metal ions. The bond lengths increase with actinide concentration, whereas highest adaptation to the bulk stabilised zirconia structure was observed for U---O and Np---O bonds. The Zr---O bond shows only a slight increase from 2.14 A at 6 mol% actinide to 2.18 A at infinite dilution in UO{sub 2} and NpO{sub 2}. The short interatomic distance between Zr and the surrounding oxygen and metal atoms indicate a low relaxation of Zr with respect to the bulk structure, i.e. a strong Pauling behaviour. -- Graphical abstract: Metal-oxygen bond distances in (Zr,Lu,U)O{sub 2-x} solid solutions with different oxygen vacancy concentrations (Lu/Zr=1 and Lu/Zr=0.5). Display Omitted Research Highlights: {yields} EXAFS indicates high U and Np adaption to the bulk structure of stabilised zirconia. {yields} Zr---O bond length is 2.18 A at infinite Zr dilution in UO{sub 2} and NpO{sub 2}. {yields} Low relaxation (strong Pauling behaviour) of Zr explains its low solubility in UO{sub 2}.

  8. Carbon Dioxide Separation from Flue Gas by Phase Enhanced Absorption

    SciTech Connect (OSTI)

    Tim Fout

    2007-06-30

    A new process, phase enhanced absorption, was invented. The method is carried out in an absorber, where a liquid carrier (aqueous solution), an organic mixture (or organic compound), and a gas mixture containing a gas to be absorbed are introduced from an inlet. Since the organic mixture is immiscible or at least partially immiscible with the liquid carrier, the organic mixture forms a layer or small parcels between the liquid carrier and the gas mixture. The organic mixture in the absorber improves mass transfer efficiency of the system and increases the absorption rate of the gas. The organic mixture serves as a transportation media. The gas is finally accumulated in the liquid carrier as in a conventional gas-liquid absorption system. The presence of the organic layer does not hinder the regeneration of the liquid carrier or recovery of the gas because the organic layer is removed by a settler after the absorption process is completed. In another aspect, the system exhibited increased gas-liquid separation efficiency, thereby reducing the costs of operation and maintenance. Our study focused on the search of the organic layer or transportation layer to enhance the absorption rate of carbon dioxide. The following systems were studied, (1) CO{sub 2}-water system and CO{sub 2}-water-organic layer system; (2) CO{sub 2}-Potassium Carbonate aqueous solution system and CO{sub 2}-Potassium Carbonate aqueous solution-organic layer system. CO{sub 2}-water and CO{sub 2}-Potassium Carbonate systems are the traditional gas-liquid absorption processes. The CO{sub 2}-water-organic layer and CO{sub 2}-Potassium Carbonate-organic layer systems are the novel absorption processes, phase enhanced absorption. As we mentioned early, organic layer is used for the increase of absorption rate, and plays the role of transportation of CO{sub 2}. Our study showed that the absorption rate can be increased by adding the organic layer. However, the enhanced factor is highly depended on the liquid mass transfer coefficients for the CO{sub 2}-water-organic layer system. For the CO{sub 2}-Potassium Carbonate aqueous solution-organic layer system, the enhanced factor is not only dependent on the liquid mass transfer coefficients, but also the chemical reaction rates.

  9. Lyman Alpha Absorption in The Cosmic Web

    E-Print Network [OSTI]

    J. Richard Bond; James W. Wadsley

    1997-10-10

    We describe large scale structure at high redshift in terms of the Cosmic Web picture for {S,Lambda,O,H}CDM models: how galactic-scale ``peak-patches'', filaments and membranes create an interconnected intergalactic medium. The ideas are applied to our Ly$\\alpha$ forest simulations of ``shear-field patches''. We discuss simulation method and design, resolution dependence, the statistical combination of patches, UV flux scaling, and whether filtered Zel'dovich maps are useful. The response to changes in power spectrum shape and amplitude, and in cosmological parameters, is described. We also show Omega_b h^2 derived from UV rescaling is overestimated if the resolution is not adequate.

  10. Photodissociation of carbon dioxide in singlet valence electronic states. II. Five state absorption spectrum and vibronic assignment

    E-Print Network [OSTI]

    Grebenshchikov, Sergy Yu

    2013-01-01

    The absorption spectrum of CO$_2$ in the wavelength range 120\\,nm --- 160\\,nm is analyzed by means of quantum mechanical calculations performed using vibronically coupled PESs of five singlet valence electronic states and the coordinate dependent transition dipole moment vectors. The thermally averaged spectrum, calculated for T=190\\,K via Boltzmann averaging of optical transitions from many initial rotational states, accurtely reproduces the experimental spectral envelope, consisting of a low and a high energy band, the positions of the absorption maxima, their FWHMs, peak intensities, and frequencies of diffuse structures in each band. Contributions of the vibronic interactions due to Renner-Teller coupling, conical intersections, and the Herzberg-Teller effect are isolated and the calculated bands are assigned in terms of adiabatic electronic states. Finally, diffuse structures in the calculated bands are vibronically assigned using wave functions of the underlying resonance states. It is demonstrated that...

  11. First-Principles Calculation of Principal Hugoniot and K-Shell X-ray Absorption Spectra for Warm Dense KCl

    E-Print Network [OSTI]

    Zhao, Shijun; Kang, Wei; Li, Zi; Zhang, Ping; He, Xian-Tu

    2015-01-01

    Principal Hugoniot and K-shell X-ray absorption spectra of warm dense KCl are calculated using the first-principles molecular dynamics method. Evolution of electronic structures as well as the influence of the approximate description of ionization on pressure (caused by the underestimation of the energy gap between conduction bands and valence bands) in the first-principles method are illustrated by the calculation. Pressure ionization and thermal smearing are shown as the major factors to prevent the deviation of pressure from global accumulation along the Hugoniot. In addition, cancellation between electronic kinetic pressure and virial pressure further reduces the deviation. The calculation of X-ray absorption spectra shows that the band gap of KCl persists after the pressure ionization of the $3p$ electrons of Cl and K taking place at lower energy, which provides a detailed understanding to the evolution of electronic structures of warm dense matter.

  12. Method and apparatus for aerosol particle absorption spectroscopy

    DOE Patents [OSTI]

    Campillo, Anthony J. (Nesconset, NY); Lin, Horn-Bond (Manorville, NY)

    1983-11-15

    A method and apparatus for determining the absorption spectra, and other properties, of aerosol particles. A heating beam source provides a beam of electromagnetic energy which is scanned through the region of the spectrum which is of interest. Particles exposed to the heating beam which have absorption bands within the band width of the heating beam absorb energy from the beam. The particles are also illuminated by light of a wave length such that the light is scattered by the particles. The absorption spectra of the particles can thus be determined from an analysis of the scattered light since the absorption of energy by the particles will affect the way the light is scattered. Preferably the heating beam is modulated to simplify the analysis of the scattered light. In one embodiment the heating beam is intensity modulated so that the scattered light will also be intensity modulated when the particles absorb energy. In another embodiment the heating beam passes through an interferometer and the scattered light reflects the Fourier Transform of the absorption spectra.

  13. Development of an Ionic-Liquid Absorption Heat Pump

    SciTech Connect (OSTI)

    Holcomb, Don

    2011-03-29

    Solar Fueled Products (SFP) is developing an innovative ionic-liquid absorption heat pump (ILAHP). The development of an ILAHP is extremely significant, as it could result in annual savings of more than 190 billion kW h of electrical energy and $19 billion. This absorption cooler uses about 75 percent less electricity than conventional cooling and heating units. The ILAHP also has significant environmental sustainability benefits, due to reduced CO2 emissions. Phase I established the feasibility and showed the economic viability of an ILAHP with these key accomplishments: • Used the breakthrough capabilities provided by ionic liquids which overcome the key difficulties of the common absorption coolers. • Showed that the theoretical thermodynamic performance of an ILAHP is similar to existing absorption-cooling systems. • Established that the half-effect absorption cycle reduces the peak generator temperature, improving collector efficiency and reducing collector area. • Component testing demonstrated that the most critical components, absorber and generator, operate well with conventional heat exchangers. • Showed the economic viability of an ILAHP. The significant energy savings, sustainability benefits, and economic viability are compelling reasons to continue the ILAHP development.

  14. Investigation of the tripoli porous structure by small-angle neutron scattering

    SciTech Connect (OSTI)

    Avdeev, M. V.; Blagoveshchenskii, N. M.; Garamus, V. M.; Novikov, A. G. Puchkov, A. V.

    2011-12-15

    The characteristics of the tripoli porous structure have been investigated by small-angle neutron scattering (SANS). Tripoli is a finely porous sedimentary rock formed by small spherical opal particles. Its main component is aqueous silica SiO{sub 2} {center_dot} nH{sub 2}O (80-90%). Tripoli is widely used in practice as a working medium for sorption filters and in some other commercial and construction technologies. The shape of the experimental SANS curves indicates the presence of small and large pores in tripoli. The small-pore size was estimated to be {approx}100 Angstrom-Sign . The size of large pores turned out to be beyond the range of neutron wave vector transfers Q that are available for the instrument used; however, their size was indirectly estimated to be {approx}(2000-2500) Angstrom-Sign . The pores of both groups behave as surfacetype fractal scatterers with the fractal dimension D {approx} 2.2-2.6. The densities of pores of these two groups differ by approximately three orders of magnitude ({approx}10{sup 16} and {approx}10{sup 13} cm{sup -3} for small and large pores, respectively); the fraction of large pores amounts to 70-80% of the total pore volume. The found pore characteristics (their densities, sizes, and relative volumes) are in satisfactory agreement (when a comparison is possible) with the absorption data.

  15. Lyman Alpha Absorption and Tidal Debris

    E-Print Network [OSTI]

    Simon L. Morris

    1994-09-29

    The origin and evolution of structure in the Universe is one of the major questions occupying astronomers today. An understanding of the Lyalpha absorbers seen in QSO spectra is an important part of this program since such absorbers can be traced back to very high redshifts. Their mere existence places constraints on the physical state of the intergalactic medium. The discovery of Lyalpha absorbers at low redshift allows us to estimate for the first time what fraction of low redshift Lyalpha absorbers are (i) randomly distributed, (ii) distributed like galaxies but not physically associated with luminous objects, (iii) actually part of the halos of luminous galaxies, or (iv) tidal tails within galaxy groups. Results from the sightline to the QSO 3C273 suggest that the majority of the absorbers are not associated with galaxies, but that there is a significant subset that are. The absorbers associated with galaxies may be produced in enormous gaseous disks surrounding normal spiral galaxies, or may be tidal material bound up in small groups of galaxies

  16. Integrated simulation of ELM Triggered by Pellet Through Energy Absorption and Transport Enhancement

    E-Print Network [OSTI]

    Integrated simulation of ELM Triggered by Pellet Through Energy Absorption and Transport Enhancement

  17. Integrated Simulation of ELM Triggered by Pellet through Energy Absorption and Transport Enhancement

    E-Print Network [OSTI]

    Integrated Simulation of ELM Triggered by Pellet through Energy Absorption and Transport Enhancement

  18. Backscatter absorption gas imaging systems and light sources therefore

    DOE Patents [OSTI]

    Kulp, Thomas Jan (Livermore, CA); Kliner, Dahv A. V. (San Ramon, CA); Sommers, Ricky (Oakley, CA); Goers, Uta-Barbara (Campbell, NY); Armstrong, Karla M. (Livermore, CA)

    2006-12-19

    The location of gases that are not visible to the unaided human eye can be determined using tuned light sources that spectroscopically probe the gases and cameras that can provide images corresponding to the absorption of the gases. The present invention is a light source for a backscatter absorption gas imaging (BAGI) system, and a light source incorporating the light source, that can be used to remotely detect and produce images of "invisible" gases. The inventive light source has a light producing element, an optical amplifier, and an optical parametric oscillator to generate wavelength tunable light in the IR. By using a multi-mode light source and an amplifier that operates using 915 nm pump sources, the power consumption of the light source is reduced to a level that can be operated by batteries for long periods of time. In addition, the light source is tunable over the absorption bands of many hydrocarbons, making it useful for detecting hazardous gases.

  19. Fundamentals of PV Efficiency: Limits for Light Absorption

    E-Print Network [OSTI]

    M. Ryyan Khan; Xufeng Wang; Muhammad A. Alam

    2012-12-13

    A simple thermodynamic argument related to a (weakly absorbing) finite dielectric slab illuminated by sunlight- originally suggested by Yablonovich- leads to the conclusion that the absorption in a dielectric can at best be increased by a factor 4n2. Therefore, the absorption in these materials is always imperfect; the Shockley-Queisser limit can be achieved only asymptotically. In this paper, we make the connection between the degradation in efficiency and the Yablonovich limit explicit and re-derive the 4n2 limit by intuitive geometrical arguments based on Snell's law and elementary rules of probability. Remarkably, the re-derivation suggests strategies of breaking the traditional limit and improving PV efficiency by enhanced light absorption.

  20. Localized electrical fine tuning of passive microwave and radio frequency devices

    DOE Patents [OSTI]

    Findikoglu, Alp T. (Los Alamos, NM)

    2001-04-10

    A method and apparatus for the localized electrical fine tuning of passive multiple element microwave or RF devices in which a nonlinear dielectric material is deposited onto predetermined areas of a substrate containing the device. An appropriate electrically conductive material is deposited over predetermined areas of the nonlinear dielectric and the signal line of the device for providing electrical contact with the nonlinear dielectric. Individual, adjustable bias voltages are applied to the electrically conductive material allowing localized electrical fine tuning of the devices. The method of the present invention can be applied to manufactured devices, or can be incorporated into the design of the devices so that it is applied at the time the devices are manufactured. The invention can be configured to provide localized fine tuning for devices including but not limited to coplanar waveguides, slotline devices, stripline devices, and microstrip devices.

  1. Broadband Coherent Enhancement of Transmission and Absorption in Disordered Media

    E-Print Network [OSTI]

    Hsu, Chia Wei; Bromberg, Yaron; Stone, A Douglas; Cao, Hui

    2015-01-01

    We study the optimal diffusive transmission and absorption of broadband or polychromatic light in a disordered medium. By introducing matrices describing broadband transmission and reflection, we formulate an extremal eigenvalue problem where the optimal input wavefront is given by the corresponding eigenvector. We show analytically that a single wavefront can exhibit strongly enhanced total transmission or total absorption across a bandwidth that is orders of magnitude broader than the spectral correlation width of the medium, due to long-range correlations in coherent diffusion. We find excellent agreement between the analytic theory and numerical simulations.

  2. Detection of OH absorption against PSR B1718-35

    E-Print Network [OSTI]

    Anthony H. Minter

    2008-01-05

    OH absorption against PSR B1718-35 at (l,b) =351.688,+0.671 has been discovered at 1665 and 1667 MHz using the Green Bank Telescope. The absorption appears to arise at the interface of an HII region and a molecular cloud which are likely associated with the high mass star forming region NGC 6334. Beam dilution is found to be the cause of differences in the opacity of the OH against the Galactic background continuum emission and against the pulsar. The OH cloud is approximately 3 by 1.3 pc and is located behind the HII region.

  3. Detection and Quantification of Expansive Clay Minerals in Geologically-Diverse Texas Aggregate Fines 

    E-Print Network [OSTI]

    Russell, George 1983-

    2012-11-28

    minerals identified from XRD pattern of Jones Mill clay ???... 48 4.2 Rankin clay with HIM plateau at 12 ? of ?Mg, RT? treatment ............... 48 4.3 Armor aggregate with palygorskite (10.6 ?) and sepiolite (12.2 ?) ?.. 49 4.4 Fibrous palygorskite... and sepiolite minerals in Armor clay (29000X) ?. 50 4.5 Clay mineral quantities in aggregate fines (- 2 mm starting material) ?. 54 4.6 SEM image of high-crystallinity kaolinite ?books? in Rankin fines ?? 59 4.7 SEM images of Scarmado, Tolar, and Yarrington...

  4. POC-Scale Testing of an Advanced Fine Coal Dewatering Equipment/Technique

    SciTech Connect (OSTI)

    B. K. Karekh; D. Tao; J. G. Groppo

    1998-08-28

    Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 mm) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20% level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy's program to show that ultra-clean coal could be effectively dewatered to 20% or lower moisture using either conventional or advanced dewatering techniques. The cost-sharing contract effort is for 45 months beginning September 30, 1994. This report discusses technical progress made during the quarter from January 1 ? March 31, 1998.

  5. Engineering development of advanced physical fine coal cleaning for premium fuel applications

    SciTech Connect (OSTI)

    Smit, F.J.; Jha, M.C.; Phillips, D.I.; Yoon, R.H.

    1997-04-25

    The goal of this project is engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. Its scope includes laboratory research and bench-scale testing on six coals to optimize these processes, followed by design and construction of a 2 t/h process development unit (PDU). Large lots of clean coal are to be produced in the PDU from three project coals. Investigation of the near-term applicability of the two advanced fine coal cleaning processes in an existing coal preparation plant is another goal of the project and is the subject of this report.

  6. Effect of Optical Brightening Agents and UV Protective Coating on Print Stability of Fine Art Substrates for Ink Jet

    E-Print Network [OSTI]

    Fleming, Paul D. "Dan"

    Center Sun Chemical Corporation ** Department of Paper Engineering, Chemical Engineering and Imaging: Ink jet 100% cotton papers with OBA: Hahnemühle Photo rag Sterling smooth Fine

  7. Carbon Dioxide Capture by Chemical Absorption: A Solvent Comparison Study

    E-Print Network [OSTI]

    of the requirements of the Degree of Doctor of Philosophy in Chemical Engineering Practice Abstract In the light1 Carbon Dioxide Capture by Chemical Absorption: A Solvent Comparison Study by Anusha Kothandaraman B. Chem. Eng. Institute of Chemical Technology, University of Mumbai, 2005 M.S. Chemical Engineering

  8. WEATHER MODIFICATION BY CARBON DUST ABSORPTION OF SOLAR ENERGY

    E-Print Network [OSTI]

    Gray, William

    WEATHER MODIFICATION BY CARBON DUST ABSORPTION OF SOLAR ENERGY by WM. M. GRAY, WM. M. FRANK, M OF SOLAR ENERGY by w. M. Gray, W. M. Frank, M. L. Corrin and C. A. Stokes Department of Atmospheric Science interception of solar energy. Growing population pressures and predicted future global food shortages dictate

  9. Quantum delocalization directs antenna absorption to photosynthetic reaction centers

    E-Print Network [OSTI]

    Felipe Caycedo-Soler; Chris A. Schroeder; Caroline Autenrieth; Robin Ghosh; Susana F. Huelga; Martin B. Plenio

    2015-04-22

    Photosynthesis -- the conversion of sunlight to chemical energy -- is fundamental for supporting life on our planet. Despite its importance, the physical principles that underpin the primary steps of photosynthesis, from photon absorption to electronic charge separation, remain to be understood in full. Previously, electronic coherence within tightly-packed light-harvesting (LH) units or within individual reaction centers (RCs) has been recognized as an important ingredient for a complete understanding of the excitation energy transfer dynamics. However, the electronic coherence across RC and LH units has been consistently neglected as it does not play a significant role during these relatively slow transfer processes. Here, we turn our attention to the absorption process, which occurs on much shorter timescales. We demonstrate that the - often overlooked - spatially extended but short-lived excitonic delocalization across RC and LH units plays a relevant role in general photosynthetic systems, as it causes a redistribution of direct absorption towards the charge separation unit. Using the complete core complex of Rhodospirillum rubrum, we verify experimentally an 80 % increase in the direct optical absorption of the RC in situ as compared to isolated RCs. Numerical calculations reveal that similar enhancements can be expected for a wide variety of photosynthetic units in both plant and bacterial systems, suggesting that this mechanism is conserved across species and providing a clear new design principle for light-harvesting nanostructures

  10. An Economic Analysis of Industrial Absorption Heat Pumps 

    E-Print Network [OSTI]

    Kaplan, S. I.; Huntley, W. R.; Perez-Blanco, H.

    1985-01-01

    OF INDUSlRIAL ABSORPl'ION HEAT PUMPS- Horacio Perez-Blanco S. I. Kaplan W. R. Huntley Oak Ridge National Laboratory Oak Ridge, Tennessee ABSlRAcr The interest in industrial absorption heat pumps in Japan raises a number of important qnes...

  11. Absorptive separation of NO from dilute off-gas

    SciTech Connect (OSTI)

    Zapfel, W.; Marr, R.; Siebenhofer, M.

    1999-04-01

    With regard to its negligible absorption properties, the separation of nitrogen monoxide from dilute off-gas is limited to bench-scale experiments. Investigation has been centered on improving the rate of absorption by the use of complex-forming additives based on iron(II) compounds. Further efforts have been made to improve the separation efficiency by the use of reactive additives. Due to the low reactivity of nitrogen monoxide, these attempts did not succeed. The oxidation of moderately concentrated off-gas with ozone and the absorption of the so-formed nitrogen dioxide have been reported. Technical as well as economical considerations do not permit the application of the process to the treatment of dilute off-gas. The principle underlying this process led to the investigation of direct oxidation of the off-gas under electrical discharge followed by absorption with aqueous diamide solution. Temperature and moisture of the off-gas have been considered, in addition to various feed contents of nitrogen monoxide. The results of this investigation show that direct oxidation of nitrogen monoxide by corona discharge is possible. The rate of conversion increases with increasing gas velocity, accompanied by a decreasing specific energy consumption. Applied to tunnel off-gas purification, the direct oxidation route seems to offer promising technical boundaries as it is accompanied by efficient particle separation.

  12. Constraining FeLoBAL outflows from absorption line variability

    E-Print Network [OSTI]

    McGraw, S M; Hamann, F W; Capellupo, D M; Gallagher, S C; Brandt, W N

    2015-01-01

    FeLoBALs are a rare class of quasar outflows with low-ionization broad absorption lines (BALs), large column densities, and potentially large kinetic energies that might be important for `feedback' to galaxy evolution. In order to probe the physical properties of these outflows, we conducted a multiple-epoch, absorption line variability study of 12 FeLoBAL quasars spanning a redshift range between 0.7 and 1.9 over rest frame time-scales of approximately 10 d to 7.6 yr. We detect absorption line variability with greater than 8 sigma confidence in 3 out of the 12 sources in our sample over time-scales of 0.6 to 7.6 yr. Variable wavelength intervals are associated with ground and excited state Fe II multiplets, the Mg II 2796, 2803 doublet, Mg I 2852, and excited state Ni II multiplets. The observed variability along with evidence of saturation in the absorption lines favors transverse motions of gas across the line of sight (LOS) as the preferred scenario, and allows us to constrain the outflow distance from th...

  13. Atomic Absorption Spectrometry Perkin Elmer 500, Chemistry & Biochemistry

    E-Print Network [OSTI]

    Gruner, Daniel S.

    Atomic Absorption Spectrometry · Perkin Elmer 500, Chemistry & Biochemistry · Perkin Elmer 560 AA calorimeter, Chemistry & Biochemistry Cell Sorting and Harvesting · B-D FacsCalibur - cell sorter, CBMG · Cell Ultracentrifuge with Scanning UV/Vis Absorbance and Rayleigh Interference, Chemistry & Biochemistry · Beckman J-6B

  14. Progress toward high-Q perfect absorption: A Fano antilaser

    E-Print Network [OSTI]

    Yu, Sunkyu; Hong, Jiho; Park, Namkyoo

    2015-01-01

    Here we propose a route to the high-Q perfect absorption of light by introducing the concept of a Fano anti-laser. Based on the drastic spectral variation of the optical phase in a Fano-resonant system, a spectral singularity for scatter-free perfect absorption can be achieved with an order of magnitude smaller material loss. By applying temporal coupled mode theory to a Fano-resonant waveguide platform, we reveal that the required material loss and following absorption Q-factor are ultimately determined by the degree of Fano spectral asymmetry. The feasibility of the Fano anti-laser is confirmed using a photonic crystal platform, to demonstrate spatio-spectrally selective heating. Our results utilizing the phase-dependent control of device bandwidths derive a counterintuitive realization of high-Q perfect conversion of light into internal energy, and thus pave the way for a new regime of absorption-based devices, including switches, sensors, thermal imaging, and opto-thermal emitters.

  15. Atomistic Models for the absorption of Oil Production Chemicals on

    E-Print Network [OSTI]

    Goddard III, William A.

    Atomistic Models for the absorption of Oil Production Chemicals on Clay minerals Sungu Hwang, Mario The atomistic simulation of the minerals in oil production Prediction of the performance of the oil production: a model for oil -19 -18 -17 -16 -15 -14 0 0.2 0.4 0.6 0.8 1 Coverage Bindingenergyper adsorbate

  16. Methods for deacidizing gaseous mixtures by phase enhanced absorption

    DOE Patents [OSTI]

    Hu, Liang

    2012-11-27

    An improved process for deacidizing a gaseous mixture using phase enhanced gas-liquid absorption is described. The process utilizes a multiphasic absorbent that absorbs an acid gas at increased rate and leads to reduced overall energy costs for the deacidizing operation.

  17. The Influence of Dust on the Absorptivity of Radiant Barriers 

    E-Print Network [OSTI]

    Noboa, Homero L.

    1993-01-01

    The purpose of this project was to model and quantify the increase of the absorptivity of radiant barriers caused by the accumulation of dust on the surface of radiant barriers. This research was the continuation of a previous work by the author...

  18. CO2 Capture by Absorption with Potassium Carbonate

    E-Print Network [OSTI]

    Rochelle, Gary T.

    CO2 Capture by Absorption with Potassium Carbonate Third Quarterly Report 2005 Quarterly Progress. #12;3 Abstract The objective of this work is to improve the process for CO2 capture by alkanolamine transfer area as IMTP#40 dumped packing. Independent measurements of CO2 solubility give a CO2 loading

  19. XRAY LINES AND ABSORPTION EDGES IN GRBS AND THEIR AFTERGLOWS

    E-Print Network [OSTI]

    Boettcher, Markus

    of Physics and Astronomy, Ohio University, Athens, OH 45701, USA ABSTRACT Absorption and Reprocessing of the reprocessing and/or absorbing material. To date, there have been only rather few detections of such features those results impose on isotropy, homogeneity, and location of the reprocessing material with respect

  20. Monitoring PVD metal vapors using laser absorption spectroscopy

    SciTech Connect (OSTI)

    Braun, D.G.; Anklam, T.M.; Berzins, L.V.; Hagans, K.G.

    1994-04-01

    Laser absorption spectroscopy (LAS) has been used by the Atomic Vapor Laser Isotope Separation (AVLIS) program for over 10 years to monitor the co-vaporization of uranium and iron in its separators. During that time, LAS has proven to be an accurate and reliable method to monitor both the density and composition of the vapor. It has distinct advantages over other rate monitors, in that it is completely non-obtrusive to the vaporization process and its accuracy is unaffected by the duration of the run. Additionally, the LAS diagnostic has been incorporated into a very successful process control system. LAS requires only a line of sight through the vacuum chamber, as all hardware is external to the vessel. The laser is swept in frequency through an absorption line of interest. In the process a baseline is established, and the line integrated density is determined from the absorption profile. The measurement requires no hardware calibration. Through a proper choice of the atomic transition, a wide range of elements and densities have been monitored (e.g. nickel, iron, cerium and gadolinium). A great deal of information about the vapor plume can be obtained from the measured absorption profiles. By monitoring different species at the same location, the composition of the vapor is measured in real time. By measuring the same density at different locations, the spatial profile of the vapor plume is determined. The shape of the absorption profile is used to obtain the flow speed of the vapor. Finally, all of the above information is used evaluate the total vaporization rate.

  1. Facilely preparation and microwave absorption properties of Fe{sub 3}O{sub 4} nanoparticles

    SciTech Connect (OSTI)

    Wang, Guiqin, E-mail: wanggq@dlut.edu.cn [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116085 (China); Chang, Yongfeng; Wang, Lifang; Liu, Lidong; Liu, Chao [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116085 (China)

    2013-03-15

    Highlights: ? A bran-new method is firstly used to fabricate Fe{sub 3}O{sub 4} nanoparticles. ? The detailed analysis of formation mechanism is discussed. ? The electromagnetic absorption properties are defined. ? The effect of nanometer-sized is considered for the excellent microwave absorption. - Abstract: The Fe{sub 3}O{sub 4} nanoparticles were prepared by a novel wet-chemical method which shows its highly synthesizing efficiency and controllability. A possible formation mechanism was also proposed to explain the synthesizing process. X-ray diffraction (XRD) and transmission electron microscope (TEM) were employed and yielded an examination of an average diameter of 77 nm of the as-synthesized Fe{sub 3}O{sub 4} nanoparticles with face-centered cubic structure. Vibrating sample magnetometer (VSM) and vector network analyzer were employed to measure the magnetic property and electromagnetic parameters of the nanoparticles, then reflection losses (RL (dB)) were calculated in the frequency range of 2–18 GHz. A large saturation magnetization (72.36 emu/g) and high coercivity (95 Oe) were determined and indicated that the Fe{sub 3}O{sub 4} nanoparticles own strong magnetic performance. Following simulation results showed that the lowest reflection loss of the sample was ?21.2 dB at 5.6 GHz with layer thickness of 6 mm. Effect of nanometer-sized further provided an explanation for the excellent microwave absorption behavior shown by the Fe{sub 3}O{sub 4} nanoparticles.

  2. Original article Water extraction by tree fine roots in the forest

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Original article Water extraction by tree fine roots in the forest floor of a temperate Fagus Germany. By field and laboratory measurements the aim was to quantify the water extraction by those tree extract more water per standing crop of root biomass and, thus, are thought to operate more economically

  3. CHP and CHPsim: A Language and Simulator for Fine-Grain Distributed Computation

    E-Print Network [OSTI]

    Martin, Alain

    1 CHP and CHPsim: A Language and Simulator for Fine-Grain Distributed Computation Alain J. Martin Abstract--This paper describes a complete and stable version of CHP and the simulator CHPsim. CHP partial versions of the language are already widely used, but CHP has never been presented as a complete

  4. Available online at www.sciencedirect.com Fine dining or fortress? Functional shifts in spider web

    E-Print Network [OSTI]

    Blackledge, Todd

    Available online at www.sciencedirect.com Fine dining or fortress? Functional shifts in spider web online 16 June 2008; MS. number: A10919) Spiders alter web architecture in response to many environmental for spiders that spin long-lasting webs such as cobwebs. The western black widow spins a three-dimensional web

  5. Avalanche: A Fine-Grained Flow Graph Model for Irregular Applications on Distributed-Memory Systems

    E-Print Network [OSTI]

    Newton, Ryan R.

    libraries [18, 30]. To address this need we propose a new C++ library, Avalanche, for expressing fine computations. However, most of these models either require specialized languages and compilers or are library generates active-message handlers. Avalanche is built as a C++ library on top of our previously

  6. Fine-Grained Entity Recognition Xiao Ling and Daniel S. Weld

    E-Print Network [OSTI]

    Anderson, Richard

    Fine-Grained Entity Recognition Xiao Ling and Daniel S. Weld Department of Computer Science and Engineering University of Washington Seattle, WA 98195-2350, U.S.A. {xiaoling, weld are common when extracting hundreds or thousands of different relations (Hoffmann, Zhang, and Weld 2010

  7. Roadmap: Crafts Textile Arts Bachelor of Fine Arts [CA-BFA-CRFT-TXTL

    E-Print Network [OSTI]

    Sheridan, Scott

    Roadmap: Crafts ­ Textile Arts ­ Bachelor of Fine Arts [CA-BFA-CRFT-TXTL] College of the Arts School of Art Catalog Year: 2012­2013 Page 1 of 2 | Last Updated: 29-May-12/JS This roadmap Core Requirement 3 See Kent Core Summary on page 2 Kent Core Requirement 3 #12;Roadmap: Crafts

  8. Roadmap: Theatre Studies Design and Technology Bachelor of Fine Arts [CA-BFA-THEA-DT

    E-Print Network [OSTI]

    Sheridan, Scott

    Roadmap: Theatre Studies ­ Design and Technology ­ Bachelor of Fine Arts [CA-BFA-THEA-DT] College This roadmap is a recommended semester-by-semester plan of study for this major. However, courses learning requirement and counts in the major GPA #12;Roadmap: Theatre Studies ­ Design and Technology

  9. Roadmap: Crafts Ceramics Bachelor of Fine Arts [CA-BFA-CRFT-CERM

    E-Print Network [OSTI]

    Sheridan, Scott

    Roadmap: Crafts ­ Ceramics ­ Bachelor of Fine Arts [CA-BFA-CRFT-CERM] College of the Arts School of Art Catalog Year: 2012­2013 Page 1 of 2 | Last Updated: 29-May-12/JS This roadmap is a recommended Core Requirement 3 See Kent Core Summary on page 2 Kent Core Requirement 3 #12;Roadmap: Crafts

  10. Fine-grained Photovoltaic Output Prediction using a Bayesian Ensemble Prithwish Chakraborty1,2

    E-Print Network [OSTI]

    Ramakrishnan, Naren

    Fine-grained Photovoltaic Output Prediction using a Bayesian Ensemble Prithwish Chakraborty1 Increasingly, local and distributed power generation e.g., through solar (photovoltaic or PV), wind, fuel cells. However, renewable power sources such as photovoltaic (PV) arrays and wind are both variable

  11. Bachelor of Fine Arts in Art: Sample Course Sequence for Field of Specialization in Studio Art

    E-Print Network [OSTI]

    Rock, Chris

    Bachelor of Fine Arts in Art: Sample Course Sequence for Field of Specialization in Studio Art FIRST YEAR Fall Spring ART 1100, Introduction to Art 1 ART 2303, Design II: Introduction 3 ART 1302, Design I: Introduction 3 ART 2304, Drawing II: Introduction 3 ART 1303, Drawing I: Introduction 3 ARTH

  12. RADIATION HARD PHOTODETECTORS BASED ON FINE-MESH PHOTOTUBES FOR CALORIMETRY IN VERY FORWARD RAPIDITY REGION

    E-Print Network [OSTI]

    Titov, Anatoly

    in the experiment CASTOR at LHC for the detection of Cherenkov radiation must provide stable operation for higher308 RADIATION HARD PHOTODETECTORS BASED ON FINE-MESH PHOTOTUBES FOR CALORIMETRY IN VERY FORWARD), the radiation fields are very high. Ionizing radiation levels reach hundreds of kGy and neutron fluences go up

  13. Fine Sediment Sources in Coastal Watersheds with Uplifted Marine Terraces in

    E-Print Network [OSTI]

    111 Fine Sediment Sources in Coastal Watersheds with Uplifted Marine Terraces in Northwest Humboldt by uplifted marine terraces. This study will help inform the efforts to improve water quality in these streams characteristics on these uplifted marine terraces, and that because of this Luffenholtz Creek will have higher

  14. Divining Rods: Pseudomonas putida as a Microbiosensor of Fine-scale Osmotic Potentials in Soil

    E-Print Network [OSTI]

    Jackson, Robert B.

    Divining Rods: Pseudomonas putida as a Microbiosensor of Fine-scale Osmotic Potentials in Soil not provide information at microscopic scales where microbes are operating. We have inserted an osmotically) as a function of osmotic potential around the bacterium. Cells can be recovered from the soil with very small

  15. Fine-Grained Remote Monitoring, Control and Pre-Paid Electrical Service in Rural Microgrids

    E-Print Network [OSTI]

    Rowe, Anthony

    Fine-Grained Remote Monitoring, Control and Pre-Paid Electrical Service in Rural Microgrids Maxim microgrid deployment in rural Les Anglais, Haiti. The system consists of a three-tiered architecture of faults like short circuits and downed lines within microgrids. Keywords--Microgrid, Deployment Experience

  16. Where is the energy spent inside my app? Fine Grained Energy Accounting on Smartphones with Eprof

    E-Print Network [OSTI]

    Zhang, Ming

    %-75% of energy in free apps is spent in third-party advertisement modules. Eprof also reveals sev- eral "wakelock in the source code. The case study highlights the fact that most of the energy in smartphone apps is spent in IWhere is the energy spent inside my app? Fine Grained Energy Accounting on Smartphones with Eprof

  17. SEDIMENT ENGINEERING THRU DREDGING AND WITH NATURE (SETDWN) FATE OF FINES IN THE DREDGING

    E-Print Network [OSTI]

    US Army Corps of Engineers

    1 SEDIMENT ENGINEERING THRU DREDGING AND WITH NATURE (SETDWN) ­ FATE OF FINES IN THE DREDGING.Coor@dep.state.fl.us Abstract: The SETDWN initiative is positioned to develop a better understanding of sediment behavior engineered actual risk based set of permit requirements. Introduction The Sediment engineering thru dredging

  18. An efficient process for recovery of fine coal from tailings of coal washing plants

    SciTech Connect (OSTI)

    Cicek, T.; Cocen, I.; Engin, V.T.; Cengizler, H. [Dokuz Eylul University, Izmir (Turkey). Dept. for Mining Engineering

    2008-07-01

    Gravity concentration of hard lignites using conventional jigs and heavy media separation equipment is prone to produce coal-rich fine tailings. This study aims to establish a fine coal recovery process of very high efficiency at reasonable capital investment and operational costs. The technical feasibility to upgrade the properties of the predeslimed fine refuse of a lignite washing plant with 35.9% ash content was investigated by employing gravity separation methods. The laboratory tests carried out with the combination of shaking table and Mozley multi-gravity separator (MGS) revealed that the clean coal with 18% ash content on dry basis could be obtained with 58.9% clean coal recovery by the shaking table stage and 4.1% clean coal recovery by MGS stage, totaling to the sum of 63.0% clean coal recovery from a predeslimed feed. The combustible recovery and the organic efficiency of the shaking table + MGS combination were 79.5% and 95.5%, respectively. Based on the results of the study, a flow sheet of a high-efficiency fine coal recovery process was proposed, which is also applicable to the coal refuse pond slurry of a lignite washing plant.

  19. Multi-gravity separator: an alternate gravity concentrator to process coal fines

    SciTech Connect (OSTI)

    Majumder, A.K.; Bhoi, K.S.; Barnwal, J.P. [Regional Research Laboratories, Bhopal (India)

    2007-08-15

    The multi-gravity separator (MGS) is a novel piece of equipment for the separation of fine and ultra-fine minerals. However, the published literature does not demonstrate its use in the separation of coal fines. Therefore, an attempt was made to study the effects of different process variables on the performance of an MGS for the beneficiation of coal fines. The results obtained from this study revealed that among the parameters studied, drum rotation and feed solids concentration play dominating roles in controlling the yield and ash content of the clean coal. Mathematical modeling equations that correlate the variables studied and the yield and ash contents of the clean coal were developed to predict the performance of an MGS under different operating and design conditions. The entire exercise revealed that the MGS could produce a clean coal with an ash content of 14.67% and a yield of 71.23% from a feed coal having an ash content of 24.61 %.

  20. Agnostic Clustering of Markovian Ran El-Yaniv Shai Fine Naftali Tishby

    E-Print Network [OSTI]

    , will be given elsewhere. 2 Measuring similarity of statistical sources The most popular information theoreticAgnostic Clustering of Markovian Sequences Ran El-Yaniv Shai Fine Naftali Tishby Institute-mail: franni,fshai,tishbyg@cs.huji.ac.il Category: Algorithms. Abstract Classi cation of nite sequences without

  1. The Case for Fine-Grained Traffic Engineering in Data Centers Theophilus Benson

    E-Print Network [OSTI]

    Akella, Aditya

    The Case for Fine-Grained Traffic Engineering in Data Centers Theophilus Benson , Ashok Anand years, several techniques have been suggested for routing and traffic engineering in data centers. How data center traf- fic patterns. Our preliminary study reveals that existing techniques can only achieve

  2. The Case for Fine-Grained Traffic Engineering in Data Centers Theophilus Benson

    E-Print Network [OSTI]

    Liblit, Ben

    Computer Sciences Department The Case for Fine-Grained Traffic Engineering in Data Centers-Grained Traffic Engineering in Data Centers Theophilus Benson , Aditya Akella and Ming Zhang University of Wisconsin-Madison; Microsoft Research Abstract Data center traffic characteristics are not well under

  3. MicroTE: Fine Grained Traffic Engineering for Data Centers Theophilus Benson

    E-Print Network [OSTI]

    Akella, Aditya

    MicroTE: Fine Grained Traffic Engineering for Data Centers Theophilus Benson , Ashok Anand , Aditya center traffic characteristics on data cen- ter traffic engineering is not well understood. In particu on the network making it appro- priate for current and future data centers. Categories and Subject Descriptors C

  4. Production of a pellet fuel from Illinois coal fines. Technical report, September 1--November 30, 1994

    SciTech Connect (OSTI)

    Rapp, D.; Lytle, J.; Berger, R.

    1994-12-31

    The primary goal of this research is to produce a pellet fuel from low-sulfur Illinois coal fines which could burn with emissions of less than 1.8 lbs SO{sub 2}/10{sup 6} Btu in stoker-fired boilers. The significance of 1.8 lbs SO{sub 2}/10{sup 6} Btu is that in the Chicago (9 counties) and St. Louis (2 counties) metropolitan areas, industrial users of coal currently must comply with this level of emissions. Stokers are an attractive market for pellets because pellets are well-suited for this application and because western coal is not a competitor in the stoker market. Compliance stoker fuels come from locations such as Kentucky and West Virginia and the price for fuels from these locations is high relative to the current price of Illinois coal. This market offers the most attractive near-term economic environment for commercialization of pelletization technology. For this effort, the authors will be investigating the use of fines from two Illinois mines which currently mine relatively low-sulfur reserves and that discard their fines fraction (minus 100 mesh). The research will involve investigation of multiple unit operations including column flotation, filtration and pellet production. The end result of the effort will allow for an evaluation of the commercial viability of the approach. This quarter pellet production work commenced and planning for collection and processing of a preparation plant fines fraction is underway.

  5. Handbook / The Fine Print / Code of Academic Honesty I. Code of Academic Honesty

    E-Print Network [OSTI]

    Wang, Jia

    Handbook / The Fine Print / Code of Academic Honesty I. Code of Academic Honesty With respect of the IIT Chicago- Kent College of Law Student Handbook (http://www.kentlaw.edu/depts/acadadm/handbook.html), and all such students should refer to the IIT Chicago-Kent College of Law Student Handbook for policies

  6. POLICY ON MANAGEMENT OF STUDENT FEES, CHARGES, FINES AND DEBTS Heriot-Watt University

    E-Print Network [OSTI]

    Painter, Kevin

    or to make good damage to its property and impose other sanctions on students for debts owed to it. 2 sanctions for debt within the framework of Ordinance 2. The underlying principles guiding the University in its administration of all its fees, charges, fines and sanctions are that its actions should, at all

  7. Fine-Grained Dynamic Voltage and Frequency Scaling for Precise Energy and Performance

    E-Print Network [OSTI]

    Pedram, Massoud

    Monitoring Unit (PMU) ! Proposed Fine-grained DVFS Policy ! Experimental Results ! Conclusion #12;2 Energy Monitoring Unit (PMU) ! PMU on the XScale processor chip can report up to 20 different dynamic events during be monitored and reported at any given time ! For DVFS, we use PMU to generate statistics for " Total no

  8. Fine-Grain Access Control for Securing Shared Resources in Computational Grids*

    E-Print Network [OSTI]

    Lee, Ruby B.

    Fine-Grain Access Control for Securing Shared Resources in Computational Grids* Abstract, grid environments, grid security, Unix accessmodel. providing an active enforcement of the security. Introduction Grid environments of the future will require an abil- ity to provide a secure execution

  9. DroidMiner: Automated Mining and Characterization of Fine-grained Malicious Behaviors in Android

    E-Print Network [OSTI]

    Gu, Guofei

    DroidMiner: Automated Mining and Characterization of Fine-grained Malicious Behaviors in Android, CA, USA {vinod, porras}@csl.sri.com Abstract Most existing malicious Android app detection approaches logic from known Android malware, abstracts this logic into a sequence of threat modalities

  10. FEPMA: Fine-Grained Event-Driven Power Meter for Android Smartphones Based on Device Driver

    E-Print Network [OSTI]

    Pedram, Massoud

    FEPMA: Fine-Grained Event-Driven Power Meter for Android Smartphones Based on Device Driver Layer for providing highly accurate and nearly instantaneous estimates of power dis- sipation in an Android smartphone the Android operating system to provide information about power/performance state changes of various

  11. A Secure Fine-Grained Access Control Mechanism for Networked Storage Systems

    E-Print Network [OSTI]

    Kubiatowicz, John D.

    A Secure Fine-Grained Access Control Mechanism for Networked Storage Systems Hsiao-Ying Lin, John@cs.nctu.edu.tw Abstract--Networked storage systems provide storage services for users over networks. Secure networked storage systems store encrypted data to guarantee data confi- dentiality. However, using encryption

  12. enovations to the Music Wing of the Fine Arts Center (FAC) began

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    level. Replacement of heating units on the upper floor, requiring removal of all ceilings on the lower rooms and offices. The redesign of the Fine Arts Center's Heating, Ventilation and Air Conditioning floor, will make possible the redesign of the new exhaust system. Classrooms, practice rooms

  13. Atomic Layer Deposition to Fine-Tune the Surface Properties and Diameters of

    E-Print Network [OSTI]

    Atomic Layer Deposition to Fine-Tune the Surface Properties and Diameters of Fabricated Nanopores 02138 Received April 23, 2004; Revised Manuscript Received May 12, 2004 ABSTRACT Atomic layer deposition. The control over the chemical and physical nature of the pore surface provided by atomic layer deposition

  14. Attribute-Based Encryption for Fine-Grained Access Control of Encrypted Data

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    Attribute-Based Encryption for Fine-Grained Access Control of Encrypted Data Vipul Goyal Omkant Pandey Amit Sahai Brent Waters § Abstract As more sensitive data is shared and stored by third-party sites on the Internet, there will be a need to encrypt data stored at these sites. One drawback

  15. Fine limestone additions to regulate setting in high volume fly ash mixtures Dale P. Bentz a,

    E-Print Network [OSTI]

    Bentz, Dale P.

    Fine limestone additions to regulate setting in high volume fly ash mixtures Dale P. Bentz a September 2011 Keywords: Blended cement High volume fly ash Isothermal calorimetry Limestone Particle size Setting Strength Ternary blend a b s t r a c t High volume fly ash (HVFA) concrete mixtures are being

  16. Bachelor of Fine Arts, Visual Art, Ceramics Emphasis, 2014-2015 Name ID# Date

    E-Print Network [OSTI]

    Barrash, Warren

    Bachelor of Fine Arts, Visual Art, Ceramics Emphasis, 2014-2015 Name ID# Date General Degree Introduction to Creative Photography 9 ART 221 Art Metals: Intro to Metalsmithing 3 ART 225 Ceramics 3 ART 226 Ceramics 3 ART 231 Beginning Sculpture 3 ART 325 Studio in Ceramics 6 ART 425 Studio in Ceramics 6 ART

  17. Bachelor of Fine Arts, Visual Art, Ceramics Emphasis, 2013-2014 Name ID# Date

    E-Print Network [OSTI]

    Barrash, Warren

    Bachelor of Fine Arts, Visual Art, Ceramics Emphasis, 2013-2014 Name ID# Date General Degree area of emphasis requirements for any specific course recommendations 6 Ceramics Emphasis Three 2 251 Introduction to Creative Photography 9 ART 221 Art Metals: Intro to Metalsmithing ART 225 Ceramics

  18. Bachelor of Fine Arts, Visual Art, Ceramics Emphasis, 2012-2013 Name ID# Date

    E-Print Network [OSTI]

    Barrash, Warren

    Bachelor of Fine Arts, Visual Art, Ceramics Emphasis, 2012-2013 Name ID# Date General Degree area of emphasis requirements for any specific course recommendations 6 Ceramics Emphasis Three 2 Ceramics 3 ART 226 Ceramics 3 ART 231 Beginning Sculpture 3 ART 325 Studio in Ceramics 6 ART 425 Studio

  19. THE INFLUENCE OF FINES CONTENT AND PANEL DENSITY ON PROPERTIES OF MIXED HARDWOOD ORIENTED STRANDBOARD1

    E-Print Network [OSTI]

    Research Associate School of Renewable Natural Resources Louisiana State University Agricultural Center-formaldehyde (PF) resin as binder. The effects of fines level and density on the panel properties were studied, including effective modulus (EM), linear expansion (LE), and swelling stresses using single-layer data

  20. Aggregate production: Fines generation during rock crushing M.S. Guimaraes a

    E-Print Network [OSTI]

    Palomino, Angelica M.

    Aggregate production: Fines generation during rock crushing M.S. Guimaraes a , J.R. Valdes b , A.M. Palomino c,, J.C. Santamarina d a Aalborg Portland, Denmark b Department of Civil and Environmental Eng; accepted 16 August 2006 Available online 25 September 2006 Abstract The energy required to crush rocks

  1. CRITICAL SHEAR STRESSES FOR EROSION AND DEPOSITION OF FINE SUSPENDED SEDIMENTS IN THE FRASER RIVER

    E-Print Network [OSTI]

    #12;CRITICAL SHEAR STRESSES FOR EROSION AND DEPOSITION OF FINE SUSPENDED SEDIMENTS IN THE FRASER C T I V E Models of cohesive sediment transport require parameters describing the erosion site specific sediments. Conventional straight flumes are not suitable for cohesive sediment studies

  2. SUPPLEMENTARY MATERIAL Fossil versus contemporary sources of fine elemental and organic carbonaceous

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    1 SUPPLEMENTARY MATERIAL Fossil versus contemporary sources of fine elemental and organic/OC ratios for biomass burning emissions. SW: softwood; HW hardwood. Reference Notes (EC/OC)bbe unc (EC., 2010 forest fire 0.043 Chow et al., 2010 wild

  3. Effects of Ambient Fine and Coarse Particles On Mortality in Phoenix, Arizona

    E-Print Network [OSTI]

    Washington at Seattle, University of

    Effects of Ambient Fine and Coarse Particles On Mortality in Phoenix, Arizona Merlise A. Clyde AND COARSE PARTICLES ON MORTALITY IN PHOENIX, ARIZONA1 Merlise A. Clyde Institute of Statistics and Decision of Washington Running Title: Particulate Pollution and Mortality in Phoenix, AZ Key Words: Bayesian Model

  4. Early-type stars observed in the ESO UVES Paranal Observatory Project - V. Time-variable interstellar absorption

    E-Print Network [OSTI]

    McEvoy, Catherine M; Dufton, Philip L; Smith, Keith T; Kennedy, Michael B; Keenan, Francis P; Lambert, David L; Welty, Daniel E; Lauroesch, James T

    2015-01-01

    The structure and properties of the diffuse interstellar medium (ISM) on small scales, sub-au to 1 pc, are poorly understood. We compare interstellar absorption-lines, observed towards a selection of O- and B-type stars at two or more epochs, to search for variations over time caused by the transverse motion of each star combined with changes in the structure in the foreground ISM. Two sets of data were used: 83 VLT- UVES spectra with approximately 6 yr between epochs and 21 McDonald observatory 2.7m telescope echelle spectra with 6 - 20 yr between epochs, over a range of scales from 0 - 360 au. The interstellar absorption-lines observed at the two epochs were subtracted and searched for any residuals due to changes in the foreground ISM. Of the 104 sightlines investigated with typically five or more components in Na I D, possible temporal variation was identified in five UVES spectra (six components), in Ca II, Ca I and/or Na I absorption-lines. The variations detected range from 7\\% to a factor of 3.6 in co...

  5. Production of Seamless Superconducting Radio Frequency Cavities from Ultra-fine Grained Niobium, Phase II Final Report

    SciTech Connect (OSTI)

    Roy Crooks, Ph.D., P.E.

    2009-10-31

    The positron and electron linacs of the International Linear Collider (ILC) will require over 14,000, nine-cell, one meter length, superconducting radio frequency (SRF) cavities [ILC Reference Design Report, 2007]. Manufacturing on this scale will benefit from more efficient fabrication methods. The current methods of fabricating SRF cavities involve deep drawing of the halves of each of the elliptical cells and joining them by high-vacuum, electron beam welding, with at least 19 circumferential welds per cavity. The welding is costly and has undesirable effects on the cavity surfaces, including grain-scale surface roughening at the weld seams. Hydroforming of seamless tubes avoids welding, but hydroforming of coarse-grained seamless tubes results in strain-induced surface roughening. Surface roughness limits accelerating fields, because asperities prematurely exceed the critical magnetic field and become normal conducting. This project explored the technical and economic feasibility of an improved processing method for seamless tubes for hydroforming. Severe deformation of bulk material was first used to produce a fine structure, followed by extrusion and flow-forming methods of tube making. Extrusion of the randomly oriented, fine-grained bulk material proceeded under largely steady-state conditions, and resulted in a uniform structure, which was found to be finer and more crystallographically random than standard (high purity) RRR niobium sheet metal. A 165 mm diameter billet of RRR grade niobium was processed into five, 150 mm I.D. tubes, each over 1.8 m in length, to meet the dimensions used by the DESY ILC hydroforming machine. Mechanical properties met specifications. Costs of prototype tube production were approximately twice the price of RRR niobium sheet, and are expected to be comparable with economies of scale. Hydroforming and superconducting testing will be pursued in subsequent collaborations with DESY and Fermilab. SRF Cavities are used to construct particle accelerators for high-energy physics research, as well as for lower energy particle accelerators, and Free Electron Lasers. These machines have applications in the fields of basic science, industrial processing, medical diagnostics, pharmaceutical research and weapons systems. The scientific community and the general public will benefit from the implementation of this technology since lower production costs will increase the availability of SRF particle accelerators.

  6. Hydrophobic Dewatering of Fine Coal. Topical report, March 1, 1995-March 31, 1997

    SciTech Connect (OSTI)

    Yoon, R.; Sohn, S.; Luttrell, J.; Phillips, D.

    1997-12-31

    Many advanced fine coal cleaning technologies have been developed in recent years under the auspices of the U.S. Department of Energy. However, they are not as widely deployed in industry as originally anticipated. An important reason for this problem is that the cleaned coal product is difficult to dewater because of the large surface area associated with fine particles. Typically, mechanical dewatering, such as vacuum filtration and centrifugation, can reduce the moisture to 20-35% level, while thermal drying is costly. To address this important industrial problem, Virginia Tech has developed a novel dewatering process, in which water is displaced from the surface of fine particulate materials by liquid butane. Since the process is driven by the hydrophobic interaction between coal and liquid butane, it was referred to as hydrophobic dewatering (HD). A fine coal sample with 21.4 pm median size was subjected to a series of bench-scale HD tests. It was a mid-vol bituminous coal obtained from the Microcel flotation columns operating at the Middle Fork coal preparation plant, Virginia. All of the test results showed that the HD process can reduce the moisture to substantially less than 10%. The process is sensitive to the amount of liquid butane used in the process relative to the solids concentration in the feed stream. Neither the intensity nor the time of agitation is critical for the process. Also, the process does not require long time for phase separation. Under optimal operating conditions, the moisture of the fine coal can be reduced to 1% by weight of coal.

  7. Geometry and continuity of fine-grained reservoir sandstones deformed within an accretionary prism - Basal Unit, West Woodbourne 

    E-Print Network [OSTI]

    Blackman, Ingrid Maria

    2004-09-30

    The Basal Unit of West Woodbourne Field in Barbados is a 250 m thick succession of finely-interbedded sandstones and mudstones deposited by Paleogene, fine-grained, deep-water systems off the northern South American margin and deformed as sediments...

  8. MS#040418-01 1 Abstract--The fine scale swimming behavior of fish can now be

    E-Print Network [OSTI]

    Linder, Stephen

    MS#040418-01 1 Abstract--The fine scale swimming behavior of fish can now be studied because evaluation of the performance of these tracking algorithms for the analysis of fine scale behavior of fish was performed using a data set of 100 fish track tracks recorded simultaneously with a multibeam sonar

  9. Feasibility Study of Single-Photon Counting Using a Fine-mesh Phototube for an Aerogel Readout

    E-Print Network [OSTI]

    R. Enomoto et al

    1994-12-14

    The fine-mesh phototube is one type of photodetector which can be used under a strong magnetic field. For an aerogel readout, the single-photon detection efficiency should be close to 100\\% in order to identify particle species. We carried out a feasibility study of single-photon counting using fine-mesh phototubes, and obtained a possible solution.

  10. Broadband optical absorption by tunable Mie resonances in silicon nanocone arrays

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Z. Y.; Zhang, R. J.; Wang, S. Y.; Key Lab. for Information Science of Electromagnetic Waves; Ames Lab., Ames, IA; Lu, M.; Chen, X.; Zheng, Y. X.; Chen, L. Y.; Ye, Z.; et al

    2015-01-15

    Nanostructure arrays such as nanowire, nanopillar, and nanocone arrays have been proposed to be promising antireflection structures for photovoltaic applications due to their great light trapping ability. In this paper, the optical properties of Si nanopillar and nanocone arrays in visible and infrared region were studied by both theoretical calculations and experiments. The results show that the Mie resonance can be continuously tuned across a wide range of wavelength by varying the diameter of the nanopillars. However, Si nanopillar array with uniform diameter exhibits only discrete resonance mode, thus can't achieve a high broadband absorption. On the other hand, themore »Mie resonance wavelength in a Si nanocone array can vary continuously as the diameters of the cross sections increase from the apex to the base. Therefore Si nanocone arrays can strongly interact with the incident light in the broadband spectrum and the absorbance by Si nanocone arrays is higher than 95% over the wavelength from 300 to 2000 nm. In addition to the Mie resonance, the broadband optical absorption of Si nanocone arrays is also affected by Wood-Rayleigh anomaly effect and metal impurities introduced in the fabrication process.« less

  11. Resonant absorption of kink MHD waves by magnetic twist in coronal loops

    E-Print Network [OSTI]

    Ebrahimi, Z

    2015-01-01

    There is ample evidences of twisted magnetic structures in the corona. This motivates us to consider the magnetic twist as the cause of Alfven frequency continuum in coronal loops, which can support the resonant absorption as the rapid damping mechanism for the observed coronal kink MHD oscillations. For a straight cylindrical compressible zero-beta thin flux tube with a magnetic twist in a thin boundary and straight magnetic field in the interior and exterior regions as well as a step-like radial density profile, we derive the dispersion relation and solve it analytically. Consequently, we obtain the frequencies and damping rates of the fundamental (l=1) and first/second overtones (l=2,3) kink (m=1) MHD modes. We conclude that the resonant absorption by the magnetic twist can justify the rapid damping of kink MHD waves observed in coronal loops. Furthermore, the magnetic twist in the inhomogeneous layer can achieve deviations from P_1/P_2=2 and P_1/P_3=3 of the same order of magnitude as in the observations.

  12. Millisecond Kinetics of Nanocrystal Cation Exchange UsingMicrofluidic X-ray Absorption Spectroscopy

    SciTech Connect (OSTI)

    Chan, Emory M.; Marcus, Matthew A.; Fakra, Sirine; Elnaggar,Mariam S.; Mathies, Richard A.; Alivisatos, A. Paul

    2007-05-07

    We describe the use of a flow-focusing microfluidic reactorto measure the kinetics of theCdSe-to-Ag2Se nanocrystal cation exchangereaction using micro-X-ray absorption spectroscopy (mu XAS). The smallmicroreactor dimensions facilitate the millisecond mixing of CdSenanocrystal and Ag+ reactant solutions, and the transposition of thereaction time onto spatial coordinates enables the in situ observation ofthe millisecond reaction with mu XAS. XAS spectra show the progression ofCdSe nanocrystals to Ag2Se over the course of 100 ms without the presenceof long-lived intermediates. These results, along with supporting stoppedflow absorption experiments, suggest that this nanocrystal cationexchange reaction is highly efficient and provide insight into how thereaction progresses in individual particles. This experiment illustratesthe value and potential of in situ microfluidic X-ray synchrotrontechniques for detailed studies of the millisecond structuraltransformations of nanoparticles and other solution-phase reactions inwhich diffusive mixing initiates changes in local bond structures oroxidation states.

  13. XRD, Photoluminescence and Optical Absorption Investigations of Cobalt-doped ZnO

    SciTech Connect (OSTI)

    Sujinnapram, Supphadate; Onreabroy, Wandee; Nantawisarakul, Tuangrak

    2009-07-07

    Zn{sub 1-x}Co{sub x}O(with x = 0, 0.01, 0.10 and 0.20) were synthesized by solid-state reaction method sintered at 600 deg. C for 12 hours. The samples were studied by X-ray diffraction (XRD), optical absorption (UV-Vis) and Photoluminescence (PL). Structural analysis by Rietveld method using XRD showed that the peaks of secondary phase Co{sub 3}O{sub 4} with a cubic structure were visible in the high-doped sample (x = 0.1, 0.2), besides the main peaks of wurtzite-like structure the same as that of ZnO. Shift of the XRD peaks proved the incorporation of Co{sup 2+} into the ZnO lattice. The band gap energy decreased from 3.18 to 3.14 eV with the increasing of cobalt concentration. PL spectra at room temperature showed the blue emission with the peak around 412 nm. In addition, the intensity of the blue emission decreased upon increasing the Co concentration, which indicated their high structural, defects and optical quality in the ZnO.

  14. Saline absorption in calcium silicate brick observed by NMR scanning

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    and structural damages, and the corrosion of steel in concrete structures, which can cause structural damages will have a direct in uence on the capillary action, viscosity, and permeability and therefore

  15. 74 MHz Discrete HII Absorption Regions Towards The Inner Galaxy

    E-Print Network [OSTI]

    Michael E. Nord; P. A. Henning; R. J. Rand; T. Joseph W. Lazio; Namir E. Kassim

    2006-03-02

    At low radio frequencies ( 1) and can be observed as discrete absorption regions against the Galactic nonthermal background emission created by Galactic cosmic ray electrons spiraling around magnetic fields. In this work we present 74 MHz observations in the region 26>l>-15, -5absorption features associated with known HII regions, and derive the brightness temperature of the Galactic cosmic ray electron synchrotron emission emanating from the column behind these regions. For the 42 HII regions with known distances, the average emissivity of the column behind the HII region is derived. 74 MHz emissivity values range between 0.3 and 1.0 Kelvin per parsec for a model assuming uniform distribution of emissivity. Methods for utilizing this type of data to model the 3-dimensional distribution of cosmic ray emissivity and the possibility of using this method to break the HII region kinematic distance degeneracy are discussed.

  16. Graphene plasmonics for light trapping and absorption engineering

    E-Print Network [OSTI]

    Zhang, Jianfa; Liu, Wei; Yuan, Xiaodong; Qin, Shiqiao

    2015-01-01

    Plasmonics can be used to improve absorption in optoelectronic devices and has been intensively studied for solar cells and photodetectors. Graphene has recently emerged as a powerful plasmonic material. It shows significantly less losses compared to traditional plasmonic materials such as gold and silver and its plasmons can be tuned by changing the Fermi energy with chemical or electrical doping. Here we propose the usage of graphene plasmonics for light trapping in optoelectronic devices and show that the excitation of localized plasmons in doped, nanostructured graphene can enhance optical absorption in its surrounding media including both bulky and two-dimensional materials by tens of times, which may lead to a new generation of highly efficient, spectrally selective photodetectors in mid-infrared and THz ranges. The proposed concept could even revolutionize the field of plasmonic solar cells if graphene plasmons in the visible and near-infrared are realized.

  17. Broadband reflectionless metasheets: Frequency-selective transmission and perfect absorption

    E-Print Network [OSTI]

    Asadchy, V S; Ra'di, Y; Khakhomov, S A; Semchenko, I V; Tretyakov, S A

    2015-01-01

    Energy of propagating electromagnetic waves can be fully absorbed in a thin lossy layer, but only in a narrow frequency band, as follows from the causality principle. On the other hand, it appears that there are no fundamental limitations on broadband matching of thin absorbing layers. However, known thin absorbers produce significant reflections outside of the resonant absorption band. In this paper we explore possibilities to realize a thin absorbing layer which produces no reflected waves in a very wide frequency range, while the transmission coefficient has a narrow peak of full absorption. Here we show, both theoretically and experimentally, that a wide-band-matched thin resonant absorber, invisible in reflection, can be realized if one and the same resonant mode of the absorbing array unit cells is utilized to create both electric and magnetic responses. We test this concept using chiral particles in each unit cells, arranged in a periodic planar racemic array, utilizing chirality coupling in each unit ...

  18. Experimental and Computational Studies of High Energy Density Plasma Streams Ablated from Fine Wires

    SciTech Connect (OSTI)

    Greenly, John B. [Cornell University; Seyler, Charles [Cornell University

    2014-03-30

    Experimental and computational studies of high energy density plasma streams ablated from fine wires. Laboratory of Plasma Studies, School of Electrical and Computer Engineering, Cornell University. Principal Investigators: Dr. John B. Greenly and Dr. Charles E. Seyler. This report summarizes progress during the final year of this project to study the physics of high energy density (HED) plasma streams of 10^17-10^20/cm3 density and high velocity (~100-500 km/s). Such streams are produced from 5-250 micrometer diameter wires heated and ionized by a 1 MA, 250 ns current pulse on the COBRA pulsed power facility at Cornell University. Plasma is ablated from the wires and is driven away to high velocity by unbalanced JxB force. A wire, or an array of wires, can persist as an essentially stationary, continuous source of this streaming plasma for >200 ns, even with driving magnetic fields of many Tesla and peak current densities in the plasma of many MA/cm2. At the heart of the ablation stream generation is the continuous transport of mass from the relatively cold, near-solid-density wire "core" into current-carrying plasma within 1 mm of the wire, followed by the magnetic acceleration of that plasma and its trapped flux to form a directed stream. In the first two years of this program, an advancing understanding of ablation physics led to the discovery of several novel wire ablation experimental regimes. In the final year, one of these new HED plasma regimes has been studied in quantitative detail. This regime studies highly reproducible magnetic reconnection in strongly radiating plasma with supersonic and superalfvenic flow, and shock structures in the outflow. The key discovery is that very heavy wires, e.g. 250 micrometer diameter Al or 150 micrometer Cu, behave in a qualitatively different way than the lighter wires typically used in wire-array Z-pinches. Such wires can be configured to produce a static magnetic X-point null geometry that stores magnetic and thermal energy; reconnection and outflow are triggered when the current begins to decrease and the electric field reverses. The reconnecting flow is driven by both magnetic and thermal pressure forces, and it has been found to be possible to vary the configuration so that one or the other dominates. The magnetic null extends into a current sheet that is heated and radiates strongly, with supersonic outflows. This is the first study of reconnection in this HED plasma regime. This compressible, radiative regime, and the triggering mechanism, may be relevant to solar and astrophysical processes. The PERSEUS extended MHD code has been developed for simulation of these phenomena, and will continue to be used and further developed to help interpret and understand experimental results, as well as to guide experimental design. The code is well-suited to simulations of shocks, and includes Hall and electron inertia physics that appear to be of importance in a number of ablation flow regimes, and definitely in the reconnection regime when gradient scales are comparable to the ion inertial scale. During the final year, our graduate student supported by this grant completed a new version of PERSEUS with the finite volume computational scheme replaced by a discontinuous Galerkin method that gives much less diffusive behavior and allows faster run time and higher spatial resolution. Thecode is now being used to study shock structures produced in the outflow region of the reconnection regime.

  19. Method for making a photodetector with enhanced light absorption

    DOE Patents [OSTI]

    Kane, James (Lawrenceville, NJ)

    1987-05-05

    A photodetector including a light transmissive electrically conducting layer having a textured surface with a semiconductor body thereon. This layer traps incident light thereby enhancing the absorption of light by the semiconductor body. A photodetector comprising a textured light transmissive electrically conducting layer of SnO.sub.2 and a body of hydrogenated amorphous silicon has a conversion efficiency about fifty percent greater than that of comparative cells. The invention also includes a method of fabricating the photodetector of the invention.

  20. A Chandra Survey of Broad Absorption Line Quasars

    E-Print Network [OSTI]

    Paul J. Green; Thomas L. Aldcroft; Smita Mathur; Belinda J. Wilkes; Martin Elvis

    2001-05-21

    We have carried out a survey with the Chandra X-ray Observatory of a sample of 10 optically bright broad absorption line (BAL) QSOs. Eight out of ten sources are detected. The 6 brightest X-ray sources have only high ionization BALs (hiBALs), while the 4 faintest all show low ionization BALs (loBALs). We perform a combined spectral fit for hiBAL QSOs to determine the mean spectral parameters of this sample. We derive an underlying best-fit power-law slope Gamma=1.8+/-0.35, consistent with the mean slope for radio-quiet quasars from ASCA, but BALQSOs require a (restframe) absorbing column of 6.5e22, with a partial covering fraction of 80%. Removing the absorption component from our best-fit spectral model yields a range of alphaOX from 1.55 to 2.28. All 6 hiBAL QSOs have de-absorbed X-ray emission consistent with non-BAL QSOs of similar luminosity. The spectral energy distributions of the hiBAL QSOs - both the underlying power-law slope and alphaOX provide the first conclusive evidence that BALQSOs have appeared to be X-ray weak because of intrinsic absorption, and that their underlying emission is consistent with non-BAL QSOs. By contrast, removal of the best-fit absorption column detected in the hiBAL QSOs still leaves the 4 loBAL QSOs as unusually X-ray faint for their optical luminosities.