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Sample records for ar kr xe

  1. The emission spectra of Ar, Kr and Xe + TEA

    Science.gov (United States)

    Suzuki, Masayo; Strock, Pierre; Sauli, Fabio; Charpak, Georges

    1987-03-01

    The emission spectra of Ar, Kr and Xe + 6% TEA gas mixtures are measured by using a single wire proportional counter as the emission source. Asymmetric emission bands are observed in the range of 270 to 350 nm, which can be attributed to the radiative deexcitation of excited TEA molecules. For the practical application of optical readout of avalanche chambers, the Ar + 2.0% TEA + 20% isobutane gas mixture is also examined, and nearly the same emission band is observed.

  2. HXeI and HXeH in Ar, Kr, and Xe matrices: experiment and simulation.

    Science.gov (United States)

    Zhu, Cheng; Niimi, Keisuke; Taketsugu, Tetsuya; Tsuge, Masashi; Nakayama, Akira; Khriachtchev, Leonid

    2015-02-07

    Experimental and theoretical studies of HXeI and HXeH molecules in Ar, Kr, and Xe matrices are presented. HXeI exhibits the H-Xe stretching bands at 1238.0 and 1239.0 cm(-1) in Ar and Kr matrices, respectively, that are blue-shifted from the HXeI band observed in a Xe matrix (1193 cm(-1)) by 45 and 46 cm(-1). These shifts are larger than those observed previously for HXeCl (27 and 16 cm(-1)) and HXeBr (37 and 23 cm(-1)); thus, the matrix effect is stronger for less stable molecules. The results for HXeI are qualitatively different from all previous results on noble-gas hydrides with respect to the frequency order between Ar and Kr matrices. For previously studied HXeCl, HXeBr, and HXeCCH, the H-Xe stretching frequency is reliably (by >10 cm(-1)) higher in an Ar matrix than in a Kr matrix. In contrast, the H-Xe stretching frequency of HXeI in an Ar matrix is slightly lower than that in a Kr matrix. HXeH absorbs in Ar and Kr matrices at 1203.2 and 1192.1 cm(-1) (the stronger band for a Kr matrix), respectively. These bands are blue-shifted from the stronger band of HXeH in a Xe matrix (1166 cm(-1)) by 37 and 26 cm(-1), and this frequency order is the same as observed for HXeCl, HXeBr, and HXeCCH but different from HXeI. The present hybrid quantum-classical simulations successfully describe the main experimental findings. For HXeI in the 〈110〉 (double substitution) site, the order of the H-Xe stretching frequencies (ν(Xe) matrices from a Xe matrix are well predicted (30 and 34 cm(-1)). Both in the theory and experiment, the order of the H-Xe stretching frequencies differs from the case of HXeCl, which suggests the adequate theoretical description of the matrix effect. For HXeH in the 〈100〉 (single substitution) site, the order of the frequencies is ν(Xe) matrices with respect to a Xe matrix (36 and 23 cm(-1)) are in a good agreement with the experiments. The present calculations predict an increase of the H-Xe stretching frequencies in the noble-gas matrices

  3. Phase behavior of mixed Ar-Kr, Ar-Xe and Kr-Xe monolayer films on graphite: a Monte Carlo study.

    Science.gov (United States)

    Patrykiejew, A

    2013-01-01

    Using Monte Carlo simulation methods in the grand canonical ensemble we have studied the behavior of mixed Ar-Kr, Ar-Xe and Kr-Xe monolayer films on the graphite basal plane. We have considered the adsorption of the lighter component, either argon or krypton, under the condition of a fixed chemical potential of the heavier component (krypton or xenon), as well as on the graphite surface with preadsorbed small amounts of a heavier noble gas. In both types of simulation the composition of the adsorbed layer is not conserved. We discuss the phase behavior of mixed films emerging from both types of 'computer experiment'. We also demonstrate that Monte Carlo simulation allows us to estimate the effects of preadsorbed xenon on the commensurate-incommensurate transition in the krypton monolayer film and gives the results that are in good quantitative agreement with experimental data.

  4. RgBF2(+) complexes (Rg = Ar, Kr, and Xe): the cations with large stabilities.

    Science.gov (United States)

    Lv, Zhi; Chen, Guang-Hui; Li, Dan; Wu, Di; Huang, Xiao-Chun; Li, Zhi-Ru; Liu, Wen-Guang

    2011-04-21

    Rare gas containing cations with general formula [Rg, B, 2F](+) have been investigated theoretically by second-order Mo̸ller-Plesset perturbation, coupled cluster, and complete active space self-consistent field levels of theory with correlation-consistent basis sets. Totally two types of minima, i.e., boron centered C(2) (v) symmetried RgBF(2) (+) (Rg = Ar, Kr, and Xe) which can be viewed as loss of F(-) from FRgBF(2) and linear FRgBF(+) (Rg = Kr and Xe) are obtained at the CCSD(T)∕aug-cc-pVTZ∕SDD and CASSCF(10,8)∕aug-cc-pVTZ∕SDD levels, respectively. It is shown that the RgBF(2) (+) are global minima followed by FRgBF(+) at 170.9 and 142.2 kcal∕mol on the singlet potential-energy surfaces of [Rg, B, 2F](+) (Rg = Kr and Xe) at the CASPT2(10,8) ∕aug-cc-pVTZ∕SDD∕∕CASSCF(10,8)∕aug-cc-pVTZ∕SDD, respectively. The interconversion barrier heights between RgBF(2) (+) and FRgBF(+) (Rg = Kr and Xe) are at least 39 kcal∕mol. In addition, no dissociation transition state associated with RgBF(2) (+) and FRgBF(+) can be found. This suggests that RgBF(2) (+) (Rg = Ar, Kr, and Xe) can exist as both thermodynamically and kinetically stable species, while linear FRgBF(+) (Rg = Kr and Xe) can exist as metastable species compared with the lowest dissociation limit energies just like isoelectronic linear FRgBO and FRgBN(-). From natural bond orbital and atoms-in-molecules calculations, it is found that the positive charge is mainly located on Rg and boron atoms for both types of minima, the Rg-B bonds of ArBF(2) (+), KrBF(2) (+), and XeBF(2) (+) are mostly electrostatic, thus can be viewed as ion-induced dipole interaction; while that of linear FKrBF(+) and FXeBF(+) are covalent in nature. The previous experimental observation of ArBF(2) (+) by Pepi et al. [J. Phys. Chem. B. 110, 4492 (2006)] should correspond to C(2) (v) minimum. The presently predicted spectroscopies of KrBF(2) (+), XeBF(2) (+), FKrBF(+), and FXeBF(+) should be helpful for their experimental

  5. Mound Facility activities in chemical and physical research: July--December 1977. [Kr-Xe and Kr-Ar diffusion; Ne-Ar thermal diffusion

    Energy Technology Data Exchange (ETDEWEB)

    1978-05-01

    Isotope separation of Ar, C, /sup 3/He, Kr, Ne, O, and Xe isotopes is reported. TiFeH/sub x/, TiCoH/sub x/, TiCuH/sub x/, and VH/sub x/ were studied using NMR (proton relaxation times). VD/sub x/ and VT/sub x/ were synthesized. The problem of calculating the valence state of Pu is discussed. A series solution to the plutonium (N,H) characteristic equation is suggested. Shipments of /sup 231/Pa, /sup 230/Th, and /sup 229/Th are reported. Separation and processing of /sup 234/U are also reported. Theoretical methods were developed to calculate temperature distributions as functions of water flow rate in liquid thermal diffusion columns. Diffusion coefficients were measured from 300 to 1200/sup 0/K for Kr-Xe and Kr-Ar. New thermal diffusion factors are submitted for Ne-Ar.

  6. Shock formation in Ne, Ar, Kr, and Xe on DD gas puff implosions

    Science.gov (United States)

    Narkis, J.; Rahman, H. U.; Wessel, F. J.; Ney, P.; Beg, F.

    2016-10-01

    1- and 2-D simulations of a 1-cm radius, gas-puff implosion of Ne, Ar, Kr, and Xe liners onto a DD target are conducted using the discharge parameters for the Univ. Nevada, Reno, Zebra (1 MA, 125 ns) voltage driver and the resistive MHD code MACH2. During the run-in phase, initial†shock heating preheats the DD plasma, with subsequent stable, adiabatic compression heating the target to high energy density. The dynamics of the former in both the liner and target are investigated. It is shown that magnetic field transport to the liner/target interface does not occur prior to the run-in phase in Ne and Ar liners, yet does occur in Kr and Xe liners, and that magnetic field transport to the interface is a requirement for shock initiation, thus demonstrating the necessity for using a high-Z material in the Staged Z-pinch. Shock reflection off the axis and subsequent collision with the interface results in partial transmission into the liner, which manifests as current reversal, and consequently an enhanced Bθ gradient. 2-D simulations show that magneto-Rayleigh-Taylor instability growth decreases with increasing Z, with shock formation providing sufficient isolation to reproduce the current reversal and enhanced Bθ gradient observed in 1-D simulations. Advanced Research Projects Agency - Energy, DE-AR0000569.

  7. Continuous Measurements of Dissolved Ne, Ar, Kr, and Xe Ratios with a Field-Deployable Gas Equilibration Mass Spectrometer.

    Science.gov (United States)

    Manning, Cara C; Stanley, Rachel H R; Lott, Dempsey E

    2016-03-15

    Noble gases dissolved in natural waters are useful tracers for quantifying physical processes. Here, we describe a field-deployable gas equilibration mass spectrometer (GEMS) that provides continuous, real-time measurements of Ne, Ar, Kr, and Xe mole ratios in natural waters. Gas is equilibrated with a membrane contactor cartridge and measured with a quadrupole mass spectrometer, after in-line purification with reactive metal alloy getters. We use an electron energy of 35 V for Ne to eliminate isobaric interferences, and a higher electron energy for the other gases to improve sensitivity. The precision is 0.7% or better and 1.0% or better for all mole ratios when the instrument is installed in a temperature-controlled environment and a variable-temperature environment, respectively. In the lab, the accuracy is 0.9% or better for all gas ratios using air as the only calibration standard. In the field (and/or at greater levels of disequilbrium), the accuracy is 0.7% or better for Ne/Kr, Ne/Ar, and Ar/Kr, and 2.5% or better for Ne/Xe, Ar/Xe, and Kr/Xe using air as the only calibration standard. The field accuracy improves to 0.6% or better for Ne/Xe, Ar/Xe, and Kr/Xe when the data is calibrated using discrete water samples run on a laboratory-based mass spectrometer. The e-folding response time is 90-410 s. This instrument enables the collection of a large number of continuous, high-precision and accuracy noble gas measurements at substantially reduced cost and labor compared to traditional methods.

  8. Kinetic study of energy transfer from He(n = 2, 3) to Ne, Ar, Kr, and Xe

    Energy Technology Data Exchange (ETDEWEB)

    Nayfeh, M.H.; Chen, C.H.; Payne, M.G.

    1976-11-01

    Time-resolved spectroscopic studies have been carried out on various emissions from He-Ar, He-Kr, He-Xe, and He-Ne mixtures to obtain kinetic information and quenching cross sections following charged-particle excitation. Our results are consistent with the pathways model of Payne, Klots, and Hurst in which Jesse effects are due primarily to energy transfer from He(2 /sup 1/S) to an atom or molecule which is consequentially ionized. Quenching cross sections for He(2 /sup 1/S) -Ar, -Kr, and -Xe at thermal (300 degreeK) collision energy were obtained as 22.5, 42, and 70 A/sup 2/, respectively, with an accuracy of 10%. These results are smaller than theoretical calculations which make use of the orbiting approximation, but agree well with experimental data obtained by crossed-molecular-beam methods. Using the same method, we obtained for the first time room-temperature quenching cross sections for He(2 /sup 1/P) -Ar and He(3 /sup 1/P) -Ne, -Ar, -Kr, -Xe (142 +- 42, 42 +- 4, 53 +- 5, 39 +- 4, and 73 +- 7 A/sup 2/, respectively). These results are larger than theoretical calculations based on the dipole-dipole mechanism by Katsuura and Watanabe. Quenching cross sections for He(3 /sup 3/P) -Ne, -Ar, -Kr, -Xe, and He(3 /sup 1/D) -Ne were obtained as 32 +- 5, 22 +- 3, 17 +- 3, 67 +- 10, and 30 +- 5 A/sup 2/, respectively. (AIP)

  9. Impact parameter moments for ionization of Ne, Ar, Kr, and Xe by protons, considering different initial states and impact energies

    CERN Document Server

    Miraglia, J E

    2016-01-01

    Tables of ab-initio total cross sections, probabilities at zero impact parameter, and impact parameter moments are presented concerning the ionization of Ne, Ar, Kr, and Xe by proton impact in the energy range (0.1-10) MeV. Calculations correspond to the continuum distorted wave eikonal initial state approximation (CDW-EIS) for energies up to 1MeV, and to the first Born approximation for larger energies. Results displayed in the tables are disaggregated for the different initial bound states, considering all shells for Ne and Ar, L-M-N shells of Kr and M-N-O shells of Xe. Our inner-shell ionization cross sections are compared with the available experimental data and with the ECPSSR results.

  10. A long-term change of the AR/KR/XE fractionation in the solar corpuscular radiation

    Science.gov (United States)

    Wieler, R.; Baur, H.; Signer, P.

    1993-01-01

    Solar noble gases in an ilmenite separate from breccia 79035 (antiquity greater than 1 Ga) were analyzed by closed system stepped etching (CSSE). All five gases show the familiar two-component structure: first solar-wind (SW) gases are released, followed by gases from solar energetic particles (SEP). Element patterns in 79035 are similar to those of 71501 ilmenite. SW-He-Ne were partly lost, but SEP-He-Ne-Ar are retained (nearly) unfractionated. Constant Ar/Kr/Xe ratios indicate that ilmenites contain an unfractionated sample of the heavy SW-SEP noble gases. Ar/Kr/Xe ratios in the solar corpuscular radiation are, however, different from 'solar system' values, whereby the Kr/Xe difference in 79035 is about twice as large as in 71501. We propose that Xe is less fractionated than Kr and Ar, though its first ionization potential (FIP) is higher than the 'cutoff' at approximately 11.5 eV, above which all elements in SEP are usually assumed to be depleted by a roughly constant factor. SW-Ne may be isotopically slightly heavier in the ancient SW trapped by 79035, as proposed earlier. In this work we extend our previous CSSE studies of solar noble gases including Kr and Xe to a lunar sample irradiated at least 1 Ga ago (breccia 79035, ilmenite separate, 42-64 microns). This sample was particularly gently etched in the first steps. Surprisingly, the first three steps, each releasing less than or equal to 0.5% of the total 36-Ar, showed an SEP-like trapped component plus relatively large concentrations of cosmogenic gases. Steps 4ff contain much less cosmogenic and more solar gas with a SW-like isotope pattern. Thus, a very minor easily etchable phase that has completely lost its SW-gases must be responsible for steps 1-3. We will not discuss these steps here and refer to the actual step 4 as the 'initial' etching step.

  11. Anionic chemistry of noble gases: formation of Mg-NG (NG = Xe, Kr, Ar) compounds under pressure.

    Science.gov (United States)

    Miao, Mao-Sheng; Wang, Xiao-Li; Brgoch, Jakoah; Spera, Frank; Jackson, Matthew G; Kresse, Georg; Lin, Hai-Qing

    2015-11-11

    While often considered to be chemically inert, the reactivity of noble gas elements at elevated pressures is an important aspect of fundamental chemistry. The discovery of Xe oxidation transformed the doctrinal boundary of chemistry by showing that a complete electron shell is not inert to reaction. However, the reductive propensity, i.e., gaining electrons and forming anions, has not been proposed or examined for noble gas elements. In this work, we demonstrate, using first-principles electronic structure calculations coupled to an efficient structure prediction method, that Xe, Kr, and Ar can form thermodynamically stable compounds with Mg at high pressure (≥125, ≥250, and ≥250 GPa, respectively). The resulting compounds are metallic and the noble gas atoms are negatively charged, suggesting that chemical species with a completely filled shell can gain electrons, filling their outermost shell(s). Moreover, this work indicates that Mg2NG (NG = Xe, Kr, Ar) are high-pressure electrides with some of the electrons localized at interstitial sites enclosed by the surrounding atoms. Previous predictions showed that such electrides only form in Mg and its compounds at very high pressures (>500 GPa). These calculations also demonstrate strong chemical interactions between the Xe 5d orbitals and the quantized interstitial quasiatom (ISQ) orbitals, including the strong chemical bonding and electron transfer, revealing the chemical nature of the ISQ.

  12. Escape factors for Paschen 2p-1s emission lines in low-temperature Ar, Kr, and Xe plasmas

    Science.gov (United States)

    Zhu, Xi-Ming; Cheng, Zhi-Wen; Pu, Yi-Kang; Czarnetzki, Uwe

    2016-06-01

    Radiation trapping phenomenon is often observed when investigating low-temperature plasmas. Photons emitted from the upper excited states may be reabsorbed by the lower states before they leave the plasmas. In order to account for this effect in the modelling and optical diagnostics of plasmas, either an ‘escape factor’ of a function of the optical depth or a strict solution of the radiation transfer equation can be employed. However, the former is more convenient in comparison and thus is widely adopted. Previous literatures have provided several simple expressions of the escape factor for the uniform plasmas. The emission line profiles are assumed to be dominated by the Doppler broadening, and the line splitting due to the hyperfine structure is not considered. This kind of expression is only valid for small atoms, e.g. Ar in low-pressure uniform discharges. Actually, the excited state density in many of the low-temperature plasmas is non-uniform and the emission line profile can be significantly influenced by the collisional broadening at medium and high pressures. In these cases, a new escape factor equation should be calculated. In this work, we study the escape factor equations for the often used 2p-1s transitions (Paschen’s notation) of the Ar, Kr, and Xe atoms. Possible non-uniform density profiles are considered. In addition, we include the line splitting due to the hyperfine structure for Kr and Xe. For the low-pressure plasmas, an escape factor expression mainly based on the Gaussian line profile is given and particularly verified by an experiment in a low-pressure capacitive discharge. For the high-pressure plasmas, an equation based on the Voigt line profile is also calculated. In this way, the new escape factor expression is ready for use in the modelling of the Ar, Kr, and Xe plasmas from low to atmospheric pressure.

  13. Peculiarities of latent track etching in SiO2/Si structures irradiated with Ar, Kr and Xe ions

    Science.gov (United States)

    Al'zhanova, A.; Dauletbekova, A.; Komarov, F.; Vlasukova, L.; Yuvchenko, V.; Akilbekov, A.; Zdorovets, M.

    2016-05-01

    The process of latent track etching in SiO2/Si structures irradiated with 40Ar (38 MeV), 84Kr (59 MeV) and 132Xe (133 and 200 MeV) ions has been investigated. The experimental results of SiO2 etching in a hydrofluoric acid solution have been compared with the results of computer simulation based on the thermal spike model. It has been confirmed that the formation of a molten region along the swift ion trajectory with minimum radius of 3 nm can serve as a theoretical criterion for the reproducible latent track etching tracks in SiO2.

  14. Dissociation energies of AgRG (RG = Ar, Kr, Xe) and AgO molecules from velocity map imaging studies

    CERN Document Server

    Cooper, Graham A; Gentleman, Alexander S; Iskra, Andreas; van Wijk, Robert; Mackenzie, Stuart R

    2015-01-01

    The near ultraviolet photodissociation dynamics of silver atom rare gas dimers have been studied by velocity map imaging. AgRG (RG = Ar, Kr, Xe) species generated by laser ablation are excited in the region of the C <- X continuum leading to direct, near threshold dissociation generating Ag* (2P3/2) + RG (1S0) products. Images recorded at excitation wavelengths throughout the C <- X continuum, coupled with known atomic energy levels, permit determination of the ground X (2SIGMA+) state dissociation energies of 85.9 +/- 23.4 cm-1 (AgAr), 149.3 +/- 22.4 cm-1 (AgKr) and 256.3 +/- 16.0 cm-1 (AgXe). Three additional photolysis processes, each yielding Ag atom photoproducts, are observed in the same spectral region. Two of these are markedly enhanced in intensity upon seeding the molecular beam with nitrous oxide, and are assigned to photodissociation of AgO at the two photon level. These features yield an improved ground state dissociation energy for AgO of 15965 +/- 81 cm-1, which is in good agreement with ...

  15. Dissociation energies of Ag-RG (RG = Ar, Kr, Xe) and AgO molecules from velocity map imaging studies.

    Science.gov (United States)

    Cooper, Graham A; Kartouzian, Aras; Gentleman, Alexander S; Iskra, Andreas; van Wijk, Robert; Mackenzie, Stuart R

    2015-09-28

    The near ultraviolet photodissociation dynamics of silver atom-rare gas dimers have been studied by velocity map imaging. Ag-RG (RG = Ar, Kr, Xe) species generated by laser ablation are excited in the region of the C ((2)Σ(+))←X ((2)Σ(+)) continuum leading to direct, near-threshold dissociation generating Ag* ((2)P3/2) + RG ((1)S0) products. Images recorded at excitation wavelengths throughout the C ((2)Σ(+))←X ((2)Σ(+)) continuum, coupled with known atomic energy levels, permit determination of the ground X ((2)Σ(+)) state dissociation energies of 85.9 ± 23.4 cm(-1) (Ag-Ar), 149.3 ± 22.4 cm(-1) (Ag-Kr), and 256.3 ± 16.0 cm(-1) (Ag-Xe). Three additional photolysis processes, each yielding Ag atom photoproducts, are observed in the same spectral region. Two of these are markedly enhanced in intensity upon seeding the molecular beam with nitrous oxide, and are assigned to photodissociation of AgO at the two-photon level. These features yield an improved ground state dissociation energy for AgO of 15 965 ± 81 cm(-1), which is in good agreement with high level calculations. The third process results in Ag atom fragments whose kinetic energy shows anomalously weak photon energy dependence and is assigned tentatively to dissociative ionization of the silver dimer Ag2.

  16. A velocity map imaging study of gold-rare gas complexes: Au-Ar, Au-Kr, and Au-Xe

    Science.gov (United States)

    Hopkins, W. Scott; Woodham, Alex P.; Plowright, Richard J.; Wright, Timothy G.; Mackenzie, Stuart R.

    2010-06-01

    The ultraviolet photodissociation dynamics of the gold-rare gas atom van der Waals complexes (Au-RG, RG=Ar, Kr, and Xe) have been studied by velocity map imaging. Photofragmentation of Au-Ar and Au-Kr at several wavelengths permits extrapolation to zero of the total kinetic energy release (TKER) spectra as monitored in the Au(P23/2∘[5d106p]) fragment channel, facilitating the determination of ground state dissociation energies of D0″(Au-Ar)=149±13 cm-1 and D0″(Au-Kr)=240±19 cm-1, respectively. In the same spectral region, transitions to vibrational levels of an Ω'=1/2 state of the Au-Xe complex result in predissociation to the lower Au(P21/2∘[5d106p])+Xe(S10[5p6]) fragment channel for which TKER extrapolation yields a value of D0″(Au-Xe)=636±27 cm-1. Asymmetric line shapes for transitions to the v'=14 level of this state indicate coupling to the Au(P23/2∘[5d106p])+Xe(S10[5p6]) continuum, which allows us to refine this value to D0″(Au-Xe)=607±5 cm-1. The dissociation dynamics of this vibrational level have been studied at the level of individual isotopologues by fitting the observed excitation spectra to Fano profiles. These fits reveal a remarkable variation in the predissociation dynamics for different Au-Xe isotopologues. For Au-Ar and Au-Xe, the determined ground state dissociation energies are in good agreement with recent theoretical calculations; the agreement of the Au-Kr value with theory is less satisfactory.

  17. Rare Gases Inserted into Biological Building Blocks: A Theoretical Study of Glycine - Rg Compounds (Rg-Xe, Kr, Ar)

    Science.gov (United States)

    Chaban, Galina M.

    2005-01-01

    Compounds formed by insertion of rare-gas atoms (Xe, Kr, and Ar) into glycine molecule are investigated using accurate ab initio computational methods. Identification of such insertion compounds may open new frontiers in the field of rare-gas chemistry, such as possible existence of biological molecules that include chemically bound rare gas atoms. The most stable glycine-Rg configuration is found to correspond to insertion of Rg atoms into the 0-H bond of glycine. These NH2CH2COORgH compounds are metastable , but separated by sizable potential barriers from the Rg + glycine dissociation products. Preliminary calculations show that NH2CH2COOXeH compound is energetically stable with respect to another (3-body) dissociation channel (NH2CH2COO + Rg + H), while the corresponding Ar species is not stable in this respect. The compound with the inserted Kr is a borderline case, with the 3-body dissociation products being close in energy to the NH2CH2COOKrH minimum.

  18. Dissociation energies of Ag–RG (RG = Ar, Kr, Xe) and AgO molecules from velocity map imaging studies

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, Graham A.; Gentleman, Alexander S.; Iskra, Andreas; Wijk, Robert van; Mackenzie, Stuart R., E-mail: stuart.mackenzie@chem.ox.ac.uk [Physical and Theoretical Chemistry Laboratory, Oxford Chemistry, South Parks Road, Oxford OX1 3QZ (United Kingdom); Kartouzian, Aras [Physical and Theoretical Chemistry Laboratory, Oxford Chemistry, South Parks Road, Oxford OX1 3QZ (United Kingdom); Department of Physical Chemistry, Catalysis Research Center, Technische Universität München, Lichtenbergstr. 4, 85748 Garching (Germany)

    2015-09-28

    The near ultraviolet photodissociation dynamics of silver atom—rare gas dimers have been studied by velocity map imaging. Ag–RG (RG = Ar, Kr, Xe) species generated by laser ablation are excited in the region of the C ({sup 2}Σ{sup +})←X ({sup 2}Σ{sup +}) continuum leading to direct, near-threshold dissociation generating Ag* ({sup 2}P{sub 3/2}) + RG ({sup 1}S{sub 0}) products. Images recorded at excitation wavelengths throughout the C ({sup 2}Σ{sup +})←X ({sup 2}Σ{sup +}) continuum, coupled with known atomic energy levels, permit determination of the ground X ({sup 2}Σ{sup +}) state dissociation energies of 85.9 ± 23.4 cm{sup −1} (Ag–Ar), 149.3 ± 22.4 cm{sup −1} (Ag–Kr), and 256.3 ± 16.0 cm{sup −1} (Ag–Xe). Three additional photolysis processes, each yielding Ag atom photoproducts, are observed in the same spectral region. Two of these are markedly enhanced in intensity upon seeding the molecular beam with nitrous oxide, and are assigned to photodissociation of AgO at the two-photon level. These features yield an improved ground state dissociation energy for AgO of 15 965 ± 81 cm{sup −1}, which is in good agreement with high level calculations. The third process results in Ag atom fragments whose kinetic energy shows anomalously weak photon energy dependence and is assigned tentatively to dissociative ionization of the silver dimer Ag{sub 2}.

  19. Metal-organic frameworks for Xe/Kr separation

    Science.gov (United States)

    Ryan, Patrick J.; Farha, Omar K.; Broadbelt, Linda J.; Snurr, Randall Q.; Bae, Youn-Sang

    2014-07-22

    Metal-organic framework (MOF) materials are provided and are selectively adsorbent to xenon (Xe) over another noble gas such as krypton (Kr) and/or argon (Ar) as a result of having framework voids (pores) sized to this end. MOF materials having pores that are capable of accommodating a Xe atom but have a small enough pore size to receive no more than one Xe atom are desired to preferentially adsorb Xe over Kr in a multi-component (Xe--Kr mixture) adsorption method. The MOF material has 20% or more, preferably 40% or more, of the total pore volume in a pore size range of 0.45-0.75 nm which can selectively adsorb Xe over Kr in a multi-component Xe--Kr mixture over a pressure range of 0.01 to 1.0 MPa.

  20. Dirac-Fock calculations of K -, L -, and M -shell fluorescence and Coster-Kronig yields for Ne, Ar, Kr, Xe, Rn, and Uuo

    Science.gov (United States)

    Sampaio, J. M.; Madeira, T. I.; Guerra, M.; Parente, F.; Santos, J. P.; Indelicato, P.; Marques, J. P.

    2015-05-01

    In this work, we calculated the fluorescence and Coster-Kronig yields for the K shell and the L and M subshells of Ne, Ar, Kr, Xe, Rn, and Uuo (Z =118 ), using a Dirac-Fock model which provides a better description of the electron-electron interaction than previous approaches, and is suitable to handle superheavy elements. The results are compared with available data from other authors. In what concerns Ne, Ar, Kr, Xe, and Rn K shells, the obtained results are in very good agreement with the adopted values of Krause [25] and with experiment when available. For the L subshells, our results are in line with existing ones. For the M subshells and for all shells of Uuo there are no previous experimental and theoretical results to compare to our calculations.

  1. Finite-element multiconfiguration Hartree-Fock calculations of the atomic quadrupole moments of excited states of Be, Al, In, Ne, Ar, Kr, and Xe

    Science.gov (United States)

    Sundholm, Dage; Olsen, Jeppe

    1993-04-01

    The atomic quadrupole moments Qzz of Be(2s2p;3P2), Al(3p;2P3/2), In(5p;2P3/2), Ne(2p53s3P2), Ar(3p54s;3P2), Kr(4p55s;3P2), and Xe(5p56s;3P2) have been calculated using a finite-element multiconfiguration Hartree-Fock method. The obtained Qzz(Be) of 2.265 a.u. agrees with previously calculated values. The calculated Qzz(Al) and Qzz(In) of 2.579 and 3.165 a.u. are in good agreement with the experimental values of 2.53(15) a.u. and 2.94(10) a.u. A large s-d polarization contribution to the Qzz of the rare gases is found in the present calculations. The correlation contributions from double (D), triple (T), and quadruple (Q) excitations to the Qzz of the rare gases alternate; the total DTQ correlation contribution is negligibly small for Ne, Ar, and Kr, while the DTQ correlation contribution to the Qzz(Xe) is 25% of the final Qzz. The final values are Qzz(Ne)=-0.0506 a.u., Qzz(Ar)=-0.0553 a.u., Qzz(Kr)=+0.0601 a.u., and Qzz(Xe)=+0.4505 a.u., as compared to the experimental values of -0.048(5) a.u., -0.042(4) a.u., +0.046(5) a.u., and +0.30(3) a.u. for Ne, Ar, Kr, and Xe, respectively.

  2. High-power gas-discharge excimer ArF, KrCl, KrF and XeCl lasers utilising two-component gas mixtures without a buffer gas

    Energy Technology Data Exchange (ETDEWEB)

    Razhev, A M; Kargapol' tsev, E S [Institute of Laser Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation); Churkin, D S [Novosibirsk State University, Novosibirsk (Russian Federation)

    2016-03-31

    Results of an experimental study of the influence of a gas mixture (laser active medium) composition on an output energy and total efficiency of gas-discharge excimer lasers on ArF* (193 nm), KrCl* (222 nm), KrF* (248 nm) and XeCl* (308 nm) molecules operating without a buffer gas are presented. The optimal ratios of gas components (from the viewpoint of a maximum output energy) of an active medium are found, which provide an efficient operation of laser sources. It is experimentally confirmed that for gas-discharge excimer lasers on halogenides of inert gases the presence of a buffer gas in an active medium is not a necessary condition for efficient operation. For the first time, in two-component gas mixtures of repetitively pulsed gas-discharge excimer lasers on electron transitions of excimer molecules ArF*, KrCl*, KrF* and XeCl*, the pulsed energy of laser radiation obtained under pumping by a transverse volume electric discharge in a low-pressure gas mixture without a buffer gas reached up to 170 mJ and a high pulsed output power (of up to 24 MW) was obtained at a FWHM duration of the KrF-laser pulse of 7 ns. The maximal total efficiency obtained in the experiment with two-component gas mixtures of KrF and XeCl lasers was 0.8%. (lasers)

  3. High-power gas-discharge excimer ArF, KrCl, KrF and XeCl lasers utilising two-component gas mixtures without a buffer gas

    Science.gov (United States)

    Razhev, A. M.; Kargapol'tsev, E. S.; Churkin, D. S.

    2016-03-01

    Results of an experimental study of the influence of a gas mixture (laser active medium) composition on an output energy and total efficiency of gas-discharge excimer lasers on ArF* (193 nm), KrCl* (222 nm), KrF* (248 nm) and XeCl* (308 nm) molecules operating without a buffer gas are presented. The optimal ratios of gas components (from the viewpoint of a maximum output energy) of an active medium are found, which provide an efficient operation of laser sources. It is experimentally confirmed that for gas-discharge excimer lasers on halogenides of inert gases the presence of a buffer gas in an active medium is not a necessary condition for efficient operation. For the first time, in two-component gas mixtures of repetitively pulsed gas-discharge excimer lasers on electron transitions of excimer molecules ArF*, KrCl*, KrF* and XeCl*, the pulsed energy of laser radiation obtained under pumping by a transverse volume electric discharge in a low-pressure gas mixture without a buffer gas reached up to 170 mJ and a high pulsed output power (of up to 24 MW) was obtained at a FWHM duration of the KrF-laser pulse of 7 ns. The maximal total efficiency obtained in the experiment with two-component gas mixtures of KrF and XeCl lasers was 0.8%.

  4. Theoretical prediction of new noble-gas molecules FNgBNR (Ng = Ar, Kr, and Xe; R = H, CH3, CCH, CHCH2, F, and OH).

    Science.gov (United States)

    Chen, Jien-Lian; Yang, Chang-Yu; Lin, Hsiao-Jing; Hu, Wei-Ping

    2013-06-28

    We have computationally predicted a new class of stable noble-gas molecules FNgBNR (Ng = Ar, Kr, Xe; R = H, CH3, CCH, CHCH2, F, and OH). The FNgBNR were found to have compact structures with F-Ng bond lengths of 1.9-2.2 Å and Ng-B bond lengths of ~1.8 Å. The endoergic three-body dissociation energies of FNgBNH to F + Ng + BNH were calculated to be 12.8, 31.7, and 63.9 kcal mol(-1), for Ng = Ar, Kr, and Xe, respectively at the CCSD(T)/CBS level. The energy barriers of the exoergic two-body dissociation to Ng + FBNH were calculated to be 16.1, 24.0, and 33.2 kcal mol(-1) for Ng = Ar, Kr, and Xe, respectively. Our results showed that the dissociation energetics is relatively insensitive to the identities of the terminal R groups. The current study suggested that a wide variety of noble-gas containing molecules with different types of R groups can be thermally stable at low temperature, and the number of potentially stable noble-gas containing molecules would thus increase very significantly. It is expected some of the FNgBNR molecules could be identified in future experiments under cryogenic conditions in noble-gas matrices or in the gas phase.

  5. Mutual Neutralization of Atomic Rare-Gas Cations (Ne+, Ar+, Kr+, Xe+) with Atomic Halide Anions (Cl-, Br-, I-)

    Science.gov (United States)

    2015-01-07

    but mixing prior to entering the flow tube through a single inlet, to yield a mixture of Rg+ cations. Experiments were conducted in Ar+/Ne+, Ar+/Xe...Johnsen and M. A. Biondi, Phys. Rev. A 20, 87–97 (1979). 25W. Lindinger, Phys. Scr . T3, 115–119 (1983). 26R. E. Olson, J. Chem. Phys. 56, 2979–2984

  6. Total cross sections for electron capture and transfer ionization by highly stripped, slow Ne, Ar, Kr, and Xe projectiles on helium

    Energy Technology Data Exchange (ETDEWEB)

    Justiniano, E.; Cocke, C.L.; Gray, T.J.; Dubois, R.; Can, C.; Waggoner, W.; Schuch, R.; Schmidt-Boecking, H.; Ingwersen, H.

    1984-03-01

    Experimental cross sections are reported for electron capture and transfer ionization for Ne, Ar, Kr, and Xe projectiles on He for charge states (q) between 2 and 13 and for projectile energies between (250 and 1000 eV)q. The double-electron capture is found to be typically an order of magnitude weaker than single-electron capture, and to be dominated in most cases by the transfer ionization channel. While gross features of the cross sections can be qualitatively understood, quantitative agreement with available theoretical model calculations is poor.

  7. A method for estimating (41)Ar, (85)(,88)Kr and (131m,133)Xe doses to non-human biota.

    Science.gov (United States)

    Vives I Batlle, J; Jones, S R; Copplestone, D

    2015-06-01

    A method is presented for estimating (41)Ar, (85,88)Kr and (131m,133)Xe dose rates to terrestrial wildlife without having to resort to comparisons with analogue radionuclides. The approach can be used to calculate the dose rates arising from external exposures to given ambient air concentrations of these isotopes. Dose conversion coefficient (DCC) values for a range of representative organisms are calculated, using a Monte Carlo approach to generate absorbed fractions based on representing animals as reference ellipsoid geometries. Plume immersion is the main component of the total DCC. DCC values calculated for a human-sized organism are compared with human dose conversion factors from ICRP Publication 119, demonstrating the consistency of the biota approach with that for humans. An example of application is provided for hypothetical nuclear power plant atmospheric discharges with associated exposures to birds and insects. In this example, the dose rates appear to be dominated by (133)Xe and (88)Kr, respectively. The biota considered would be protected from the effects of noble gas radiation from a population protection perspective.

  8. Relativistic calculations of K-, L- and M-shell X-ray production cross-sections by electron impact for Ne, Ar, Kr, Xe, Rn and Uuo

    Science.gov (United States)

    Sampaio, J. M.; Madeira, T. I.; Guerra, M.; Parente, F.; Indelicato, P.; Santos, J. P.; Marques, J. P.

    2016-10-01

    In this work, we derive X-ray production cross-sections from electron-impact ionization cross-sections for Ne, Ar, Kr, Xe, Rn, and Uuo, calculated in the modified relativistic binary-encounter-Bethe model, and using as the only input parameter the binding energies obtained in the Dirac-Fock approach. Radiative and radiationless transition probabilities necessary to compute the inter- and intra-shell atomic yields were calculated in the same approach. Shell electron-impact ionization cross-sections and X-ray production cross-sections are compared with the corresponding cross-sections retrieved from the National Institute of Standards and Technology Reference Database and available experimental data.

  9. Desorption Kinetics of Ar, Kr, Xe, N2, O2, CO, Methane, Ethane, and Propane from Graphene and Amorphous Solid Water Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R. Scott; May, Robert A.; Kay, Bruce D.

    2016-03-03

    The desorption kinetics for Ar, Kr, Xe, N2, O2, CO, methane, ethane, and propane from grapheme covered Pt(111) and amorphous solid water (ASW) surfaces are investigated using temperature programmed desorption (TPD). The TPD spectra for all of the adsorbates from graphene have well-resolved first, second, third, and multi- layer desorption peaks. The alignment of the leading edges is consistent the zero-order desorption for all of the adsorbates. An Arrhenius analysis is used to obtain desorption energies and prefactors for desorption from graphene for all of the adsorbates. In contrast, the leading desorption edges for the adsorbates from ASW do not align (for coverages < 2 ML). The non-alignment of TPD leading edges suggests that there are multiple desorption binding sites on the ASW surface. Inversion analysis is used to obtain the coverage dependent desorption energies and prefactors for desorption from ASW for all of the adsorbates.

  10. Experimental and theoretical studies of the infrared spectra and bonding properties of NgBeCO₃ and a comparison with NgBeO (Ng = He, Ne, Ar, Kr, Xe).

    Science.gov (United States)

    Zhang, Qingnan; Chen, Mohua; Zhou, Mingfei; Andrada, Diego M; Frenking, Gernot

    2015-03-19

    The novel neon complex NeBeCO3 has been prepared in a low-temperature neon matrix via codeposition of laser-evaporated beryllium atoms with O2 + CO/Ne. Doping by the heavier noble gas atoms argon, krypton and xenon yielded the associated adducts NgBeCO3 (Ng = Ar, Kr, Xe). The noble gas complexes have been identified via infrared spectroscopy. Quantum chemical calculations of NgBeCO3 and NgBeO (Ng = He, Ne, Ar, Kr, Xe) using ab initio methods and density functional theory show that the Ng-BeCO3 bonds are slightly longer and weaker than the Ng-BeO bonds. The energy decomposition analysis of the Ng-Be bonds suggests that the attractive interactions come mainly from the Ng → BeCO3 and Ng → BeO σ donation.

  11. High-order harmonic generation in Xe, Kr, and Ar driven by a 2.1-\\mu m source: high-order harmonic spectroscopy under macroscopic effects

    CERN Document Server

    Hong, Kyung-Han; Gkortsas, Vasileios-Marios; Huang, Shu-Wei; Moses, Jeffrey; Granados, Eduardo; Bhardwaj, Siddharth; Kärtner, Franz X

    2012-01-01

    We experimentally and numerically study the atomic response and pulse propagation effects of high-order harmonics generated in Xe, Kr, and Ar driven by a 2.1-\\mu m infrared femtosecond light source. The light source is an optical parametric chirped-pulse amplifier, and a modified strong-field approximation and 3-dimensional pulse propagation code are used for the numerical simulations. The extended cutoff in the long-wavelength driven high-harmonic generation has revealed the spectral shaping of high-order harmonics due to the atomic structure (or photo-recombination cross-section) and the macroscopic effects, which are the main factors of determining the conversion efficiency besides the driving wavelength. Using precise numerical simulations to determine the macroscopic electron wavepacket, we are able to extract the photo-recombination cross-sections from experimental high-order harmonic spectra in the presence of macroscopic effects. We have experimentally observed that the macroscopic effects shift the o...

  12. New Empirical Potential Energy Functions for the Heavier Homonuclear Rare Gas Pairs: {Ne}_2, {Ar}_2, {Kr}_2, and {Xe}_2

    Science.gov (United States)

    Myatt, Philip Thomas; Baker, Matthew T.; Kang, Ju-Hee; Escobar Moya, Andres; McCourt, Frederick R. W.; Le Roy, Robert J.

    2016-06-01

    The many decades of work on determining accurate analytic pair potentials for rare gas dimers from experimental data focussed largely on the use of bulk non-ideal gas and collisional properties, with the use of spectroscopic data being somewhat of an afterthought, for testing the resulting functions. This was a natural result of experimental challenges, as the very weak binding of ground-state rare gas pairs made high resolution spectroscopy a relatively late arrival as a practical tool in this area. However, we believe that it is now time for a comprehensive reassessment. Following up on a preliminary report at this meeting five years ago, this paper describes work to determine a new generation of empirical potential energy functions for the four heavier (i.e., not involving He) homonuclear rare gas pairs from direct fits to all available spectroscopic, pressure virial, and acoustic virial coefficient data, with the resulting functions being `tuned' by comparisons with available thermal transport property data: viscosity, mass diffusion and thermal diffusion, and thermal conductivity data, and tested against the best available ab initio potentials. The resulting functions are everywhere smooth and differentiable to all orders, incorporate the correct (damped) theoretical inverse-power long-range behaviour, and have sensible short-range extrapolation behaviour. R.J. Le Roy, C.J.W. Mackie, P. Chandrasekhar and K.M. Sentjens, ``Accurate New Potential Energy Functions From Spectroscopic and Virial Coefficient Data for the Ten Rare Gas Pairs formed from Ne, Ar, Kr and Xe, paper MF03 at the 66th Ohio State University International Symposium on Molecular Spectroscopy, Columbus, Ohio, June 13-17 (2011).

  13. Modeling of Kr-Xe discharge of excimer lamp

    Directory of Open Access Journals (Sweden)

    Belasri A.

    2013-03-01

    Full Text Available This paper reports the numerical simulation of Dielectric Barrier Discharge (DBD for Kr-Xe excilamp. The model of the discharge consists of three main modules: a plasma chemistry module, a circuit module and a Boltzmann equation module. The results predict the optimal operating conditions and describe the electrical and chemical properties of the KrXe* excimer lamp.

  14. Metal-organic frameworks for removal of Xe and Kr from nuclear fuel reprocessing plants.

    Science.gov (United States)

    Liu, Jian; Thallapally, Praveen K; Strachan, Denis

    2012-08-01

    Removal of xenon (Xe) and krypton (Kr) from process off-gases containing 400 ppm Xe, 40 ppm Kr, 78% N(2), 21% O(2), 0.9% Ar, 0.03% CO(2), and so forth using adsorption was demonstrated for the first time. Two well-known metal-organic frameworks (MOFs), HKUST-1 and Ni/DOBDC, which both have unsaturated metal centers but different pore morphologies, were selected as novel adsorbents. Results of an activated carbon were also included for comparison. The Ni/DOBDC has higher Xe/Kr selectivities than those of the activated carbon and the HKUST-1. In addition, results show that the Ni/DOBDC and HKUST-1 can adsorb substantial amounts of Xe and Kr even when they are mixed in air. Moreover, the Ni/DOBDC can successfully separate 400 ppm Xe from 40 ppm Kr and air containing O(2), N(2), and CO(2) with a Xe/Ke selectivity of 7.3 as indicated by our breakthrough results. This shows a promising future for MOFs in radioactive nuclide separations from spent fuels.

  15. Investigations of the Rg-BrCl (Rg = He, Ne, Ar, Kr, Xe) binary van der Waals complexes: ab initio intermolecular potential energy surfaces, vibrational states and predicted pure rotational transition frequencies

    Science.gov (United States)

    Li, Song; Zheng, Rui; Chen, Shan-Jun; Chen, Yan; Chen, Peng

    2017-03-01

    The intermolecular potential energy surfaces (PESs) of the ground electronic state for the Rg-BrCl (Rg = He, Ne, Ar, Kr, Xe) van der Waals complexes have been constructed by using the coupled-cluster method in combination with the augmented quadruple-zeta correlation-consistent basis sets supplemented with an additional set of bond functions. The features of the anisotropic PESs for these complexes are remarkably similar, which are characterized by three minima and two saddle points between them. The global minimum corresponds to a collinear Rg-Br-Cl configuration. Two local minima, correlate with an anti-linear Rg-Cl-Br geometry and a nearly T-shaped structure, can also be located on each PES. The quantum bound state calculations enable us to investigate intermolecular vibrational states and rotational energy levels of the complexes. The transition frequencies are predicted and are fitted to obtain their corresponding spectroscopic constants. In general, the periodic trends are observed for this complex family. Comparisons with available experimental data for the collinear isomer of Ar-BrCl demonstrate reliability of our theoretical predictions, and our results for the other two isomers of Ar-BrCl as well as for other members of the complex family are also anticipated to be trustable. Except for the collinear isomer of Ar-BrCl, the data presented in this paper would be beneficial to improve our knowledge for these experimentally unknown species.

  16. Investigations of the Rg-BrCl (Rg=He, Ne, Ar, Kr, Xe) binary van der Waals complexes: ab initio intermolecular potential energy surfaces, vibrational states and predicted pure rotational transition frequencies.

    Science.gov (United States)

    Li, Song; Zheng, Rui; Chen, Shan-Jun; Chen, Yan; Chen, Peng

    2017-03-05

    The intermolecular potential energy surfaces (PESs) of the ground electronic state for the Rg-BrCl (Rg=He, Ne, Ar, Kr, Xe) van der Waals complexes have been constructed by using the coupled-cluster method in combination with the augmented quadruple-zeta correlation-consistent basis sets supplemented with an additional set of bond functions. The features of the anisotropic PESs for these complexes are remarkably similar, which are characterized by three minima and two saddle points between them. The global minimum corresponds to a collinear Rg-Br-Cl configuration. Two local minima, correlate with an anti-linear Rg-Cl-Br geometry and a nearly T-shaped structure, can also be located on each PES. The quantum bound state calculations enable us to investigate intermolecular vibrational states and rotational energy levels of the complexes. The transition frequencies are predicted and are fitted to obtain their corresponding spectroscopic constants. In general, the periodic trends are observed for this complex family. Comparisons with available experimental data for the collinear isomer of Ar-BrCl demonstrate reliability of our theoretical predictions, and our results for the other two isomers of Ar-BrCl as well as for other members of the complex family are also anticipated to be trustable. Except for the collinear isomer of Ar-BrCl, the data presented in this paper would be beneficial to improve our knowledge for these experimentally unknown species.

  17. Kr/Xe Separation over a Chabazite Zeolite Membrane.

    Science.gov (United States)

    Feng, Xuhui; Zong, Zhaowang; Elsaidi, Sameh K; Jasinski, Jacek B; Krishna, Rajamani; Thallapally, Praveen K; Carreon, Moises A

    2016-08-10

    Herein we demonstrate that chabazite zeolite SAPO-34 membranes effectively separated Kr/Xe gas mixtures at industrially relevant compositions. Control over membrane thickness and average crystal size led to industrial range permeances and high separation selectivities. Specifically, SAPO-34 membranes can separate Kr/Xe mixtures with Kr permeances as high as 1.2 × 10 (-7) mol/m(2) s Pa and separation selectivities of 35 for molar compositions close to typical concentrations of these two gases in air. In addition, SAPO-34 membranes separated Kr/Xe mixtures with Kr permeances as high as 1.2 × 10 (-7) mol/m(2) s Pa and separation selectivities up to 45 for molar compositions as might be encountered in nuclear reprocessing technologies. Molecular sieving and differences in diffusivities were identified as the dominant separation mechanisms.

  18. Xe and Kr analyses of silicate inclusions from iron meteorites.

    Science.gov (United States)

    Bogard, D. D.; Huneke, J. C.; Burnett, D. S.; Wasserburg, G. J.

    1971-01-01

    Measurements have been conducted of the amounts and isotopic composition of Xe and Kr in silicate inclusions of several iron meteorites. It is shown that the Xe and Kr contents are comparable to chondritic values. The isotopic compositions show trapped gas of both chondritic and atmospheric composition. Large spallation effects occur in some of the meteorites; the spallation spectra in some instances differ from those reported for stone meteorites. In several meteorites, very large neutron capture effects on Br and I occur. All samples have pronounced Xe129 excesses which apparently indicate differences in the formation times from chondrites of less than about 100 million years; however, the presence of trapped Xe132 in silicates which were enclosed in molten Fe-Ni and cooled slowly proves that they were not entirely outgassed, so that some of the Xe129 excess may also be trapped.

  19. XeCl Avalanche discharge laser employing Ar as a diluent

    Science.gov (United States)

    Sze, Robert C.

    1981-01-01

    A XeCl avalanche discharge exciplex laser which uses a gaseous lasing starting mixture of: (0.2%-0.4% chlorine donor/2.5%-10% Xe/97.3%-89.6% Ar). The chlorine donor normally comprises HCl but can also comprise CCl.sub.4 BCl.sub.3. Use of Ar as a diluent gas reduces operating pressures over other rare gas halide lasers to near atmospheric pressure, increases output lasing power of the XeCl avalanche discharge laser by 30% to exceed KrF avalanche discharge lasing outputs, and is less expensive to operate.

  20. Kr and Xe isotopic compositions of Fe-Mn crusts from the western and central Pacific Ocean and implications for their genesis

    Institute of Scientific and Technical Information of China (English)

    BU Wenrui; SHI Xuefa; LI Li; ZHANG Mingjie; GP Glasby; LIU Jihua

    2014-01-01

    Kr and Xe nuclide abundance and isotopic ratios of the uppermost layer of Fe-Mn Crusts from the western and central Pacific Ocean have been determined. The results indicate that the Kr and Xe isotopic composi-tions, like that of He, Ne and Ar, can be classified into two types: low3He/4He type and high3He/4He type. The low3He/4He type crusts have low84Kr and132Xe abundance, while the high3He/4He type crusts have high84Kr and132Xe abundance. The82Kr/84Kr ratios of the low3He/4He type crusts are lower than that of the air, while the83Kr/84Kr and86Kr/84Kr ratios are higher than those of the air. The Kr isotopic ratios of the high-er3He/4He type crusts are quite similar to those of the air. The128Xe/132Xe,130Xe/132Xe and131Xe/132Xe ratios of the low3He/4He type sample are distinctly lower than those of the air, whereas the129Xe/132Xe,134Xe/132Xe and136Xe/132Xe ratios are higher than those of the air. The low3He/4He type samples have the diagnostic characteristics of the MORB, with excess129, 131, 132, 134, 136Xe relative to130Xe compared with the solar wind. The128Xe/132Xe,130Xe/132Xe and131Xe/132Xe ratios of the high3He/4He type samples are slightly higher than those of the air, and the129Xe/132Xe,134Xe/132Xe and136Xe/132Xe ratios are qiute similar to those of the air. The noble gases in the Fe-Mn crusts are derived from the lower mantle, and they are a mixture of lower mantle primitive component, radiogenic component and subduction recycled component. The helium isotopic ra-tios of the low mantle reservoir are predominantly controlled by primitive He (3He) and U and Th radiogenic decayed He (4He), but the isotopic ratios of the heavier noble gases, such as Ar, Kr and Xe, are controlled to different extent by recycling of subduction components. The difference of the noble isotopic compositions of the two type crusts is the result of the difference of the noble isotopic composition of the mantle source reservoir underneath the seamounts the crusts occurred, the noble

  1. Direct Observation of Xe and Kr Adsorption in a Xe-Selective Microporous Metal-Organic Framework.

    Science.gov (United States)

    Chen, Xianyin; Plonka, Anna M; Banerjee, Debasis; Krishna, Rajamani; Schaef, Herbert T; Ghose, Sanjit; Thallapally, Praveen K; Parise, John B

    2015-06-10

    The cryogenic separation of noble gases is energy-intensive and expensive, especially when low concentrations are involved. Metal-organic frameworks (MOFs) containing polarizing groups within their pore spaces are predicted to be efficient Xe/Kr solid-state adsorbents, but no experimental insights into the nature of the Xe-network interaction are available to date. Here we report a new microporous MOF (designated SBMOF-2) that is selective toward Xe over Kr under ambient conditions, with a Xe/Kr selectivity of about 10 and a Xe capacity of 27.07 wt % at 298 K. Single-crystal diffraction results show that the Xe selectivity may be attributed to the specific geometry of the pores, forming cages built with phenyl rings and enriched with polar -OH groups, both of which serve as strong adsorption sites for polarizable Xe gas. The Xe/Kr separation in SBMOF-2 was investigated with experimental and computational breakthrough methods. These experiments showed that Kr broke through the column first, followed by Xe, which confirmed that SBMOF-2 has a real practical potential for separating Xe from Kr. Calculations showed that the capacity and adsorption selectivity of SBMOF-2 are comparable to those of the best-performing unmodified MOFs such as NiMOF-74 or Co formate.

  2. Matrix effect on vibrational frequencies: experiments and simulations for HCl and HNgCl (Ng = Kr and Xe).

    Science.gov (United States)

    Kalinowski, Jaroslaw; Gerber, R Benny; Räsänen, Markku; Lignell, Antti; Khriachtchev, Leonid

    2014-03-01

    We study the environmental effect on molecules embedded in noble-gas (Ng) matrices. The experimental data on HXeCl and HKrCl in Ng matrices is enriched. As a result, the H-Xe stretching bands of HXeCl are now known in four Ng matrices (Ne, Ar, Kr, and Xe), and HKrCl is now known in Ar and Kr matrices. The order of the H-Xe stretching frequencies of HXeCl in different matrices is ν(Ne) Kr) Kr) Kr stretching frequencies of HKrCl is consistently ν(Kr) < ν(Ar). These matrix effects are analyzed theoretically by using a number of quantum chemical methods. The calculations on these molecules (HCl, HXeCl, and HKrCl) embedded in single Ng(') layer cages lead to very satisfactory results with respect to the relative matrix shifts in the case of the MP4(SDQ) method whereas the B3LYP-D and MP2 methods fail to fully reproduce these experimental results. The obtained order of frequencies is discussed in terms of the size available for the Ng hydrides in the cages, probably leading to different stresses on the embedded molecule. Taking into account vibrational anharmonicity produces a good agreement of the MP4(SDQ) frequencies of HCl and HXeCl with the experimental values in different matrices. This work also highlights a number of open questions in the field.

  3. VUV emission spectra from binary rare gas mixtures near the resonance lines of Xe I and Kr I

    CERN Document Server

    Morozov, A; Gerasimov, G; Arnesen, A; Hallin, R

    2003-01-01

    Emission spectra of Xe-X (X = He, Ne, Ar and Kr) and of Kr-Y (Y = He, Ne and Ar) mixtures with low concentrations of the heavier gases (0.1-1%) and moderate total pressures (50-200 hPa) have been recorded near each of the two resonance lines of Xe and Kr in DC glow capillary discharges. The recorded intense emissions have narrow spectral profiles with FWHM of about 0.1 nm. The profiles are very similar in shape to profiles of known high resolution absorption spectra recorded at comparable gas pressures. A tentative identification of the emission structures is given, which involves transitions in heteronuclear molecules and quasimolecules between weakly-bound states.

  4. Characterization and Modeling of Materials for Kr-Xe Separations

    Energy Technology Data Exchange (ETDEWEB)

    Forster, Paul [Univ. of Nevada, Las Vegas, NV (United States); Naduvalath, Balakrishnan [Univ. of Nevada, Las Vegas, NV (United States); Czerwinski, Ken [Univ. of Nevada, Las Vegas, NV (United States)

    2015-11-16

    We sought to identify practical adsorbents for the separation of Kr from Xe through pressure swing adsorption. We spent appreciable efforts on two categories of materials: metal-organic frameworks (MOFs) and zeolites. MOFs represent a new and exciting sorbent with numerous new framework topologies and surface chemistries. Zeolites are widely used and available commercial adsorbents. We have employed a combination of gas sorption analysis to analyze gas – surface interactions, computational modelling to both aid in interpreting experimental results and to predict practical adsorbents, and in-situ crystallographic studies to confirm specific experimental results.

  5. Xe/Kr Selectivity Measurements using AgZ-PAN at Various Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Garn, Troy Gerry [Idaho National Lab. (INL), Idaho Falls, ID (United States); Greenhalgh, Mitchell Randy [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, Tony Leroy [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-05-01

    In preparation for planned FY-15 Xe/Kr multi-column testing, a series of experiments were performed to determine the selectivity of Xe over Kr using the silver converted mordenite-polyacrylonitrile (AgZ-PAN) sorbent. Results from these experiments will be used for parameter selection guidelines to define test conditions for Kr gas capture purity evaluations later this year. The currently configured experimental test bed was modified by installing a new cooling apparatus to permit future multi-column testing with independent column temperature control. The modified test bed will allow for multi-column testing to facilitate a Xe separation followed by a Kr separation using engineered form sorbents. Selectivity experiments were run at temperatures of 295, 250 and 220 K. Two feed gas compositions of 1000 ppmv Xe, 150 ppmv Kr in either a He or an air balance were used. AgZ-PAN sorbent selectivity was calculated using Xe and Kr capacity determinations. AgZ-PAN sorbent selectivities for Xe over Kr of 72 were calculated at room temperature (295 K) using the feed gas with a He balance and 34 using the feed gas with an air balance. As the test temperatures were decreased the selectivity of Xe over Kr also decreased due to an increase in both Xe and Kr capacities. At 220 K, the sorbent selectivities for Xe over Kr were 22 using the feed gas with a He balance and 28 using the feed gas with an air balance. The selectivity results indicate that AgZ-PAN used in the first column of a multi-column configuration will provide adequate partitioning of Xe from Kr in the tested temperature range to produce a more pure Kr end product for collection.

  6. Anisotropic collision-induced Raman scattering by the Kr:Xe gas mixture.

    Science.gov (United States)

    Dixneuf, S; Chrysos, M; Rachet, F

    2009-08-21

    We report anisotropic collision-induced Raman scattering intensities by the Kr-Xe atomic pair recorded in a gas mixture of Kr and Xe at room temperature. We compare them to quantum-mechanical calculations on the basis of modern incremental polarizability models of either ab initio post-Hartree-Fock or density functional theory methods.

  7. Nuclear-pumped lasing of /He-3/-Xe and /He-3/-Kr

    Science.gov (United States)

    De Young, R. J.; Jalufka, N. W.; Hohl, F.

    1977-01-01

    The letter reports direct nuclear pumping of (He-3)-Xe and (He-3)-Kr using the volumetric He-3(n,p)H-3 nuclear reaction. Lasing in (He-3)-Xe was achieved at the 2.027-micron transition of Xe I; lasing in (He-3)-Kr is assumed to have occurred at the 2.52-micron transition of Kr I. Experimental results show that laser output in (He-3)-Xe increases and tends to saturate with increasing pressure, the lasing neutron-flux threshold decreases with decreasing neutron pulse, and maximum output occurs between 0.1% and 0.5% Xe with the total pressure held constant at 400 torr and with an average neutron flux of 6 by 10 to the 15th power per sq cm/sec. It is noted that the (He-3)-Xe laser has the lowest lasing-threshold neutron flux of any He-3 nuclear-pumped laser to date, but the (He-3)-Kr laser has a very high threshold flux. The primary lasing mechanism is believed to be Penning ionization of Xe and Kr followed by collisional radiative recombination and cascading into the upper laser level.

  8. Abundances of s-process elements in planetary nebulae: Br, Kr & Xe

    CERN Document Server

    Zhang, Y; Pellegrini, E; Cavagnolo, K; Baldwin, J A; Sharpee, B; Phillips, M; Liu, X W

    2006-01-01

    We identify emission lines of post-iron peak elements in very high signal-to-noise spectra of a sample of planetary nebulae. Analysis of lines from ions of Kr and Xe reveals enhancements in most of the PNe, in agreement with the theories of s-process in AGB star. Surprisingly, we did not detect lines from Br even though s-process calculations indicate that it should be produced with Kr at detectable levels.

  9. 低温下活性炭吸附分离Kr和Xe%Separation of Kr and Xe by Active Carbon Absorption Method at Low Temperature

    Institute of Scientific and Technical Information of China (English)

    陈莉云; 张昌云; 武山; 曾宝珠; 刘龙波; 杨静

    2013-01-01

    The absorption and separation method of Xe and Kr gas by active carbon was investigated. A standard mixture of Xe and Kr flowed through the active carbon column to be absorbed and enriched at low temperature ( - 78 ?). The absorbed Xe and Kr were then deabsorbed from the carbon column separately. The analysis of the experimental data shows that the recoveries of Xe and Kr are greater than 90%. It can be concluded that the decontamination coefficient for Xe from Kr environment is above 104 , while the decontamination coefficient for Kr from Xe is no less than 103.%研究了低温下活性炭吸附分离Kr和Xe的方法.Kr和Xe混合气在-78℃活性炭吸附柱上进行富集,根据Kr、Xe在活性炭柱上脱附条件的差异实现了Kr和Xe的分离.结果表明,Kr和Xe的回收率均大于900%,Kr样品中Xe的去污系数达104以上,Xe样品中Kr的去污系数达103以上.

  10. Laser-induced quadrupole-quadrupole collisional energy transfer in Xe-Kr

    Institute of Scientific and Technical Information of China (English)

    Lu Zhen-Zhong; Chen De-Ying; Fan Rong-Wei; Xia Yuan-Qin

    2011-01-01

    By considering the relative velocity distribution function and multipole expansion interaction Hamiltonian, a three-state model for calculating the cross section of laser-induced quadrupole-quadrupole collisional energy transfer is presented. Calculated results in Xe-Kr system show that in the present system, the laser-induced collision process occurs for ~4 ps, which is much shorter than the dipole-dipole laser-induced collisional energy transfer (LICET) process.The spectrum of laser-induced quadrupole-quadrupole collisional energy transfer in Xe-Kr system has wider tunable range in an order of magnitude than the dipole-dipole LICET spectra. The peak cross section decreases and moves to the quasi-static wing with increasing temperature and the full width at half peak of the profile becomes larger as the system temperature increases.

  11. Molecular hydrogen and catalytic combustion in the production of hyperpolarized 83Kr and 129Xe MRI contrast agents

    Science.gov (United States)

    Rogers, Nicola J.; Hill-Casey, Fraser; Stupic, Karl F.; Six, Joseph S.; Lesbats, Clémentine; Rigby, Sean P.; Fraissard, Jacques; Pavlovskaya, Galina E.; Meersmann, Thomas

    2016-03-01

    Hyperpolarized (hp) 83Kr is a promising MRI contrast agent for the diagnosis of pulmonary diseases affecting the surface of the respiratory zone. However, the distinct physical properties of 83Kr that enable unique MRI contrast also complicate the production of hp 83Kr. This work presents a previously unexplored approach in the generation of hp 83Kr that can likewise be used for the production of hp 129Xe. Molecular nitrogen, typically used as buffer gas in spin-exchange optical pumping (SEOP), was replaced by molecular hydrogen without penalty for the achievable hyperpolarization. In this particular study, the highest obtained nuclear spin polarizations were P = 29% for 83Kr and P = 63% for 129Xe. The results were reproduced over many SEOP cycles despite the laser-induced on-resonance formation of rubidium hydride (RbH). Following SEOP, the H2 was reactively removed via catalytic combustion without measurable losses in hyperpolarized spin state of either 83Kr or 129Xe. Highly spin-polarized 83Kr can now be purified for the first time, to our knowledge, to provide high signal intensity for the advancement of in vivo hp 83Kr MRI. More generally, a chemical reaction appears as a viable alternative to the cryogenic separation process, the primary purification method of hp 129Xe for the past 2 1/2 decades. The inherent simplicity of the combustion process will facilitate hp 129Xe production and should allow for on-demand continuous flow of purified and highly spin-polarized 129Xe.

  12. Tabletop Ultrabright Kiloelectronvolt X-Ray Sources from Xe and Kr Hollow Atom States

    Science.gov (United States)

    Sankar, Poopalasingam

    Albert Einstein, the father of relativity, once said, "Look deep into nature, and then you will understand everything better". Today available higher resolution tabletop tool to look deep into matters and living thing is an x-ray source. Although the available tabletop x-rays sources of the 20th century, such as the ones used for medical or dental x-rays are tremendously useful for medical diagnostics and industry, a major disadvantage is that they have low quality skillful brightness, which limits its resolution and accuracy. In the other hand, x-ray free-electrons laser (XFEL) and synchrotron radiation sources provided extreme bright x-rays. However, number of applications of XFEL and synchrotron such as medical and industrials, has been hampered by their size, complexity, and cost. This has set a goal of demonstrating x-ray source with enough brightness for potential applications in an often-called tabletop compact x-ray source that could be operated in university laboratory or hospitals. We have developed two tabletop ultrabright keV x-ray sources, one from a Xe hollow-atom states and the other one from Kr hollow-atom stares with a unique characteristic that makes them complementary to currently-available extreme-light sources; XFEL, and synchrotron x-ray source. Upgraded tabletop ultra-fast KrF* pump-laser interacts with target rare-gas clusters and produces hollow-atom states, which later coherently collapse to the empty inner-shell and thereby generate keV x-ray radiation. The KrF* pump-laser beam is self-focused and forms a self-channel to guide the generated x-ray radiation in the direction of the pump-laser beam to produce directed x-ray beam. Xe (M) x-ray source operates at 1.2-1.6 nm wavelength while the Kr(L) x-ray source operates in 600-800 pm wavelength. System is mounted upon 3 optical-tables (5´x12´) with two KrF amplifiers at a repetition rate of 0.1 Hz. A lower bound for brightness value for both Xe and Kr x-ray sources is 1026 photons s-1mm-2

  13. 3c/4e [small sigma, Greek, circumflex]-type long-bonding competes with ω-bonding in noble-gas hydrides HNgY (Ng = He, Ne, Ar, Kr, Xe, Rn; Y = F, Cl, Br, I): a NBO/NRT perspective.

    Science.gov (United States)

    Zhang, Guiqiu; Li, Hong; Weinhold, Frank; Chen, Dezhan

    2016-03-21

    Noble-gas hydrides HNgY are frequently described as a single ionic form (H-Ng)(+)Y(-). We apply natural bond orbital (NBO) and natural resonance theory (NRT) analyses to a series of noble-gas hydrides HNgY (Ng = He, Ne, Ar, Kr, Xe, Rn; Y = F, Cl, Br, I) to gain quantitative insight into the resonance bonding of these hypervalent molecules. We find that each of the studied species should be better represented as a resonance hybrid of three leading resonance structures, namely, H-Ng(+ -):Y (I), H:(- +)Ng-Y (II), and H^Y (III), in which the "ω-bonded" structures I and II arise from the complementary donor-acceptor interactions nY → σ*HNg and nH → σ*NgY, while the "long-bond" ([small sigma, Greek, circumflex]-type) structure III arises from the nNg → [small sigma, Greek, circumflex]*HY/[small sigma, Greek, circumflex]HY interaction. The bonding for all of the studied molecules can be well described in terms of the continuously variable resonance weightings of 3c/4e ω-bonding and [small sigma, Greek, circumflex]-type long-bonding motifs. Furthermore, we find that the calculated bond orders satisfy a generalized form of "conservation of bond order" that incorporates both ω-bonding and long-bonding contributions [viz., (bHNg + bNgY) + bHY = bω-bonding + blong-bonding = 1]. Such "conservation" throughout the title series implies a competitive relationship between ω-bonding and [small sigma, Greek, circumflex]-type long-bonding, whose variations are found to depend in a chemically reasonable manner on the electronegativity of Y and the outer valence-shell character of the central Ng atom. The calculated bond orders are also found to exhibit chemically reasonable correlations with bond lengths, vibrational frequencies, and bond dissociation energies, in accord with Badger's rule and related empirical relationships. Overall, the results provide electronic principles and chemical insight that may prove useful in the rational design of noble-gas hydrides of

  14. Transport properties in dilute UN (X ) solid solutions (X =Xe ,Kr )

    Science.gov (United States)

    Claisse, Antoine; Schuler, Thomas; Lopes, Denise Adorno; Olsson, Pär

    2016-11-01

    Uranium nitride (UN) is a candidate fuel for current GEN III fission reactors, for which it is investigated as an accident-tolerant fuel, as well as for future GEN IV reactors. In this study, we investigate the kinetic properties of gas fission products (Xe and Kr) in UN. Binding and migration energies are obtained using density functional theory, with an added Hubbard correlation to model f electrons, and the occupation matrix control scheme to avoid metastable states. These energies are then used as input for the self-consistent mean field method which enables to determine transport coefficients for vacancy-mediated diffusion of Xe and Kr on the U sublattice. The magnetic ordering of the UN structure is explicitly taken into account, for both energetic and transport properties. Solute diffusivities are compared with experimental measurements and the effect of various parameters on the theoretical model is carefully investigated. We find that kinetic correlations are very strong in this system, and that despite atomic migration anisotropy, macroscopic solute diffusivities show limited anisotropy. Our model indicates that the discrepancy between experimental measurements probably results from different irradiation conditions, and hence different defect concentrations.

  15. Electron correlation effects on photoionization time delay in atomic Ar and Xe

    Science.gov (United States)

    Ganesan, A.; Saha, S.; Decshmukh, P. C.; Manson, S. T.; Kheifets, A. S.

    2016-05-01

    Time delay studies in photoionization processes have stimulated much interest as they provide valuable dynamical information about electron correlation and relativistic effects. In a recent work on Wigner time delay in the photoionization of noble gas atoms, it was found that correlations resulting from interchannel coupling involving shells with different principal quantum numbers have significant effects on 2s and 2p photoionization of Ne, 3s photoionization of Ar, and 3d photoionization of Kr. In the present work, photoionization time delay in inner and outer subshells of the noble gases Ar and Xe are examined by including electron correlations using different many body techniques: (i) the relativistic-random-phase approximation (RRPA), (ii) RRPA with relaxation, to include relaxation effects of the residual ion and (iii) the relativistic multiconfiguration Tamm-Dancoff (RMCTD) approximation. The (sometimes substantial) effects of the inclusion of non-RPA correlations on the photoionization Wigner time delay are reported. Work supported by DOE, Office of Chemical Sciences and DST (India).

  16. Understanding the adsorption mechanism of noble gases Kr and Xe in CPO-27-Ni, CPO-27-Mg, and ZIF-8.

    Science.gov (United States)

    Magdysyuk, O V; Adams, F; Liermann, H-P; Spanopoulos, I; Trikalitis, P N; Hirscher, M; Morris, R E; Duncan, M J; McCormick, L J; Dinnebier, R E

    2014-11-21

    An experimental study of Xe and Kr adsorption in metal-organic frameworks CPO-27-Ni, CPO-27-Mg, and ZIF-8 was carried out. In situ synchrotron X-ray powder diffraction experiments allowed precise determination of the adsorption sites and sequence of their filling with increasing of gas pressure at different temperatures. Structural investigations were used for interpretation of gas adsorption measurements.

  17. A first-principles study of He, Xe, Kr and O incorporation in thorium carbide

    Science.gov (United States)

    Pérez Daroca, D.; Llois, A. M.; Mosca, H. O.

    2015-05-01

    Thorium-based materials are currently being investigated in relation with their potential utilization in Generation-IV reactors as nuclear fuels. Understanding the incorporation of fission products and oxygen is very important to predict the behavior of nuclear fuels. A first approach to this goal is the study of the incorporation energies and stability of these elements in the material. By means of first-principles calculations within the framework of density functional theory, we calculate the incorporation energies of He, Xe, Kr and O atoms in Th and C vacancy sites, in tetrahedral interstitials and in Schottky defects along the and directions. We also analyze atomic displacements, volume modifications and Bader charges. This kind of results for ThC, to the best authors' knowledge, have not been obtained previously, neither experimentally, nor theoretically. This should deal as a starting point towards the study of the complex behavior of fission products in irradiated ThC.

  18. Ar and Kr concentrations in nitrogen as a measure of the 39Ar and 85Kr activities in connection with the solar neutrino experiment BOREXINO.

    Science.gov (United States)

    Zuzel, G; Simgen, H; Heusser, G

    2004-01-01

    Among other radionuclides, 39Ar and 85Kr are potential background sources in the solar neutrino detector BOREXINO. The expected low event rate requires that the nitrogen used in the experiment needs to have lower concentrations than 0.5 microBq/m3 for 39Ar and 0.2 microBq/m3 for 85Kr, corresponding to volume concentrations in N2 of 0.4 x 10(-6)m3/m3 for Ar and 0.2 x 10(-12)m3/m3 for Kr. Applying gas mass spectrometry and special care in the sampling technique we succeeded in finding the required purity. In addition, we studied the possibility to purify nitrogen from Kr by the adsorption method.

  19. Photoionisation study of Xe.CF4 and Kr.CF4 van-der-Waals molecules.

    Science.gov (United States)

    Alekseev, V A; Garcia, G A; Kevorkyants, R; Nahon, L

    2016-05-14

    We report on photoionization studies of Xe.CF4 and Kr.CF4 van-der-Waals complexes produced in a supersonic expansion and detected using synchrotron radiation and photoelectron-photoion coincidence techniques. The ionization potential of CF4 is larger than those of the Xe and Kr atoms and the ground state of the Rg.CF4 (+) ion correlates with Rg(+) ((2)P3/2) + CF4. The onset of the Rg.CF4 (+) signals was found to be only ∼0.2 eV below the Rg ionization potential. In agreement with experiment, complementary ab initio calculations show that vertical transitions originating from the potential minimum of the ground state of Rg.CF4 terminate at a part of the potential energy surfaces of Rg.CF4 (+), which are approximately 0.05 eV below the Rg(+) ((2)P3/2) + CF4 dissociation limit. In contrast to the neutral complexes, which are most stable in the face geometry, for the Rg.CF4 (+) ions, the calculations show that the minimum of the potential energy surface is in the vertex geometry. Experiments which have been performed only with Xe.CF4 revealed no Xe.CF4 (+) signal above the first ionization threshold of Xe, suggesting that the Rg.CF4 (+) ions are not stable above the first dissociation limit.

  20. The C3-bending vibrational levels of the C3-Kr and C3-Xe van der Waals complexes studied by their Ã-X̃ electronic transitions and by ab initio calculations.

    Science.gov (United States)

    Chao, Jun-Mei; Tham, Keng Seng; Zhang, Guiqiu; Merer, Anthony J; Hsu, Yen-Chu; Hu, Wei-Ping

    2011-02-21

    Fluorescence excitation spectra and wavelength-resolved emission spectra of the C(3)-Kr and C(3)-Xe van der Waals (vdW) complexes have been recorded near the 2(2-)(0), 2(2+)(0), 2(4-)(0), and 1(1)(0) bands of the Ã(1)Π(u)-X̃(1)Σ(g)(+) system of the C(3) molecule. In the excitation spectra, the spectral features of the two complexes are red-shifted relative to those of free C(3) by 21.9-38.2 and 34.3-36.1 cm(-1), respectively. The emission spectra from the à state of the Kr complex consist of progressions in the two C(3)-bending vibrations (ν(2), ν(4)), the vdW stretching (ν(3)), and bending vibrations (ν(6)), suggesting that the equilibrium geometry in the X̃ state is nonlinear. As in the Ar complex [Zhang et al., J. Chem. Phys. 120, 3189 (2004)], the C(3)-bending vibrational levels of the Kr complex shift progressively to lower energy with respect to those of free C(3) as the bending quantum number increases. Their vibrational structures could be modeled as perturbed harmonic oscillators, with the dipole-induced dipole terms of the Ar and Kr complexes scaled roughly by the polarizabilities of the Ar and Kr atoms. Emission spectra of the Xe complex, excited near the Ã, 2(2-) level of free C(3), consist only of progressions in even quanta of the C(3)-bending and vdW modes, implying that the geometry in the higher vibrational levels (υ(bend) ≥ 4, E(vib) ≥ 328 cm(-1)) of the X̃ state is (vibrationally averaged) linear. In this structure the Xe atom bonds to one of the terminal carbons nearly along the inertial a-axis of bent C(3). Our ab initio calculations of the Xe complex at the level of CCSD(T)∕aug-cc-pVTZ (C) and aug-cc-pVTZ-PP (Xe) predict that its equilibrium geometry is T-shaped (as in the Ar and Kr complexes), and also support the assignment of a stable linear isomer when the amplitude of the C(3) bending vibration is large (υ(4) ≥ 4).

  1. Neutron-Capture Kr-80 and Ar-36 in the Martian Atmosphere and Regolith

    Science.gov (United States)

    Rao, M. N.; Bogard, D. D.; Nyquist, L.; McKay, D. S.; Masarik, J.

    2001-01-01

    We calculate that approximately 10% of martian atmospheric Kr-80 formed by neutron capture on Mars in approx. 0.5 Ga. The regolith contains even larger amounts of n-capture Kr-80 and Ar-36, which may provide clues to the evolution of the martian regolith and atmosphere. Additional information is contained in the original extended abstract.

  2. Understanding the adsorption mechanism of noble gases Kr and Xe in CPO-27-Ni, CPO-27-Mg, and ZIF-8

    OpenAIRE

    Magdysyuk, O V; ADAMS, F; Liermann, H-P.; Spanopoulos, I; Trikalitis, P N; M. Hirscher; Morris, R. E.; Duncan, M J; McCormick, L J; Dinnebier, R. E.

    2014-01-01

    An experimental study of Xe and Kr adsorption in metal-organic frameworks CPO-27-Ni, CPO-27-Mg, and ZIF-8 was carried out. In situ synchrotron X-ray powder diffraction experiments allowed precise determination of the adsorption sites and sequence of their filling with increasing of gas pressure at different temperatures. Structural investigations were used for interpretation of gas adsorption measurements. Postprint Peer reviewed

  3. A first-principles study of He, Xe, Kr and O incorporation in thorium carbide

    Energy Technology Data Exchange (ETDEWEB)

    Pérez Daroca, D., E-mail: pdaroca@tandar.cnea.gov.ar [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica, Av. General Paz 1499, 1650 San Martín, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas, 1033 Buenos Aires (Argentina); Llois, A.M. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica, Av. General Paz 1499, 1650 San Martín, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas, 1033 Buenos Aires (Argentina); Mosca, H.O. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica, Av. General Paz 1499, 1650 San Martín, Buenos Aires (Argentina); Instituto de Tecnología Jorge A. Sabato, UNSAM-CNEA, Av. General Paz 1499, 1650 San Martín, Buenos Aires (Argentina)

    2015-05-15

    Thorium-based materials are currently being investigated in relation with their potential utilization in Generation-IV reactors as nuclear fuels. Understanding the incorporation of fission products and oxygen is very important to predict the behavior of nuclear fuels. A first approach to this goal is the study of the incorporation energies and stability of these elements in the material. By means of first-principles calculations within the framework of density functional theory, we calculate the incorporation energies of He, Xe, Kr and O atoms in Th and C vacancy sites, in tetrahedral interstitials and in Schottky defects along the 〈1 1 1〉 and 〈1 0 0〉 directions. We also analyze atomic displacements, volume modifications and Bader charges. This kind of results for ThC, to the best authors’ knowledge, have not been obtained previously, neither experimentally, nor theoretically. This should deal as a starting point towards the study of the complex behavior of fission products in irradiated ThC.

  4. Kr II and Xe II axial velocity distribution functions in a cross-field ion source

    Science.gov (United States)

    Lejeune, A.; Bourgeois, G.; Mazouffre, S.

    2012-07-01

    Laser induced fluorescence measurements were carried out in a cross-field ion source to examine the behaviour of the axial ion velocity distribution functions (VDFs) in the expanding plasma. In the present paper, we focus on the axial VDFs of Kr II and Xe II ions. We examine the contourplots in a 1D-phase space (x,vx) representation in front of the exhaust channel and along the centerline of the ion source. The main ion beam, whose momentum corresponds to the ions that are accelerated through the whole potential drop, is observed. A secondary structure reveals the ions coming from the opposite side of the channel. We show that the formation of the neutralized ion flow is governed by the annular geometry. The assumption of a collisionless shock or a double layer due to supersonic beam interaction is not necessary. A non-negligible fraction of slow ions originates in local ionization or charge-exchange collision events between ions of the expanding plasma and atoms of the background residual gas. Slow ions that are produced near the centerline in the vicinity of the exit plane are accelerated toward the source body with a negative velocity leading to a high sputtering of front face. On the contrary, the ions that are produced in the vicinity of the channel exit plane are partially accelerated by the extended electric field.

  5. Generation of the organo-rare gas dications HCCRg2+ (Rg = Ar and Kr) in the reaction of acetylene dications with rare gases.

    Science.gov (United States)

    Ascenzi, Daniela; Tosi, Paolo; Roithová, Jana; Ricketts, Claire L; Schröder, Detlef; Lockyear, Jessica F; Parkes, Michael A; Price, Stephen D

    2008-12-21

    Using doubly ionized acetylene as a superelectrophilic reagent, the new rare-gas compounds HCCAr2+ and HCCKr2+ have been prepared for the first time in hyperthermal collisions of mass-selected C2H2(2+) with neutral rare gases (Rg). However, electron transfer from the rare gas to the acetylene dication as well as proton transfer from C2H2(2+) to the rare gas efficiently compete with formation of HCCRg2+. The computational investigations show that the formation of HCCRg2+ from acetylene dication is endothermic with Rg = He, Ne, Ar and Kr and only weakly exothermic with Xe. These energetic factors, as well as the pronounced competition with the other reactive channels help to explain why HCCRg2+ is only observed with Rg = Ar and Kr.

  6. Multi-Column Experimental Test Bed Using CaSDB MOF for Xe/Kr Separation

    Energy Technology Data Exchange (ETDEWEB)

    Welty, Amy Keil [Idaho National Lab. (INL), Idaho Falls, ID (United States); Greenhalgh, Mitchell Randy [Idaho National Lab. (INL), Idaho Falls, ID (United States); Garn, Troy Gerry [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-03-01

    Processing of spent nuclear fuel produces off-gas from which several volatile radioactive components must be separated for further treatment or storage. As part of the Off-gas Sigma Team, parallel research at INL and PNNL has produced several promising sorbents for the selective capture of xenon and krypton from these off-gas streams. In order to design full-scale treatment systems, sorbents that are promising on a laboratory scale must be proven under process conditions to be considered for pilot and then full-scale use. To that end, a bench-scale multi-column system with capability to test multiple sorbents was designed and constructed at INL. This report details bench-scale testing of CaSDB MOF, produced at PNNL, and compares the results to those reported last year using INL engineered sorbents. Two multi-column tests were performed with the CaSDB MOF installed in the first column, followed with HZ-PAN installed in the second column. The CaSDB MOF column was placed in a Stirling cryocooler while the cryostat was employed for the HZ-PAN column. Test temperatures of 253 K and 191 K were selected for the first column while the second column was held at 191 K for both tests. Calibrated volume sample bombs were utilized for gas stream analyses. At the conclusion of each test, samples were collected from each column and analyzed for gas composition. While CaSDB MOF does appear to have good capacity for Xe, the short time to initial breakthrough would make design of a continuous adsorption/desorption cycle difficult, requiring either very large columns or a large number of smaller columns. Because of the tenacity with which Xe and Kr adhere to the material once adsorbed, this CaSDB MOF may be more suitable for use as a long-term storage solution. Further testing is recommended to determine if CaSDB MOF is suitable for this purpose.

  7. Absorption spectra of e-beam-excited Ne, Ar, and Kr, pure and in binary mixtures.

    Science.gov (United States)

    Levchenko, A O; Ustinovskii, N N; Zvorykin, V D

    2010-10-21

    A technique using the broadband emission of a laser plume as probe radiation is applied to record UV-visible (190-510 nm) absorption spectra of Ne, Ar, and Kr, pure and in binary mixtures under moderate e-beam excitation up to 1 MW/cm(3). In all the rare gases and mixtures, the absorption spectra show continuum related to Rg(2) (+) homonuclear ions [peaking at λ∼285, 295, and 320 nm in Ne, Ar, and Kr(Ar/Kr), respectively] and a number of atomic lines related mainly to Rg(∗)(ms) levels, where m is the lowest principal quantum number of the valence electron. In argon, a continuum related to Ar(2) (∗) (λ∼325 nm) is also recorded. There are also trains of narrow bands corresponding to Rg(2) (∗)(npπ (3)Π(g))←Rg(2) (∗)(msσ (3)Σ(u) (+)) transitions. All the spectral features mentioned above were reported in literature but have never been observed simultaneously. Although charge transfer to a homonuclear ion of the heavier additive is commonly believed to dominate in binary rare-gas mixtures, it is found in this study that in Ne/Kr mixture, the charge is finally transferred from the buffer gas Ne(2) (+) ion not to Kr(2) (+) but to heteronuclear NeKr(+) ion.

  8. Understanding the Adsorption Mechanism of Xe and Kr in a Metal-Organic Framework from X-ray Structural Analysis and First-Principles Calculations.

    Science.gov (United States)

    Ghose, Sanjit K; Li, Yan; Yakovenko, Andrey; Dooryhee, Eric; Ehm, Lars; Ecker, Lynne E; Dippel, Ann-Christin; Halder, Gregory J; Strachan, Denis M; Thallapally, Praveen K

    2015-05-21

    Enhancement of adsorption capacity and separation of radioactive Xe/Kr at room temperature and above is a challenging problem. Here, we report a detailed structural refinement and analysis of the synchrotron X-ray powder diffraction data of Ni-DODBC metal organic framework with in situ Xe and Kr adsorption at room temperature and above. Our results reveal that Xe and Kr adsorb at the open metal sites, with adsorption geometries well reproduced by DFT calculations. The measured temperature-dependent adsorption capacity of Xe is substantially larger than that for Kr, indicating the selectivity of Xe over Kr and is consistent with the more negative adsorption energy (dominated by van der Waals dispersion interactions) predicted from DFT. Our results reveal critical structural and energetic information about host-guest interactions that dictate the selective adsorption mechanism of these two inert gases, providing guidance for the design and synthesis of new MOF materials for the separation of environmentally hazardous gases from nuclear reprocessing applications.

  9. Superficial Velocity Effects on HZ-PAN and AgZ-PAN for Kr/Xe Capture

    Energy Technology Data Exchange (ETDEWEB)

    Welty, Amy Keil [Idaho National Lab. (INL), Idaho Falls, ID (United States); Garn, Troy Gerry [Idaho National Lab. (INL), Idaho Falls, ID (United States); Greenhalgh, Mitchell Randy [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-04-01

    Nearly all previous testing of HZ-PAN and AgZ-PAN was conducted at the same flow rate in order to maintain consistency among tests. This testing was sufficient for sorbent capacity determinations, but did not ensure that sorbents were capable of functioning under a range of flow regimes. Tests were conducted on both HZ-PAN and AgZ-PAN at superficial velocities between 20 and 700 cm/min. For HZ-PAN, Kr capacity increased from 60 mmol/kg to 110 mmol/kg as superficial velocity increased from 21 to 679 cm/min. Results for AgZ-PAN were similar, with capacity ranging from 72 to 124 mmol/kg over the same range of superficial. These results are promising for scaling up to process flows, demonstrating flexibility to operate in a broad range of superficial velocities while maintaining sorbent capacity. While preparing for superficial velocity testing it was also discovered that AgZ-PAN Xe capacity, previously observed to diminish over time, could be recovered with increased desorption temperature. Further, a substantial Xe capacity increase was observed. Previous room temperature capacities in the range of 22-25 mmol Xe/kg AgZ-PAN were increased to over 60 mmol Xe/kg AgZ-PAN. While this finding has not yet been fully explored to optimize activation and desorption temperatures, it is encouraging.

  10. Theoretical study of the electronic structure of the ArKr* exciplex

    Science.gov (United States)

    Spiegelmann, F.; Gadea, F. X.; Castex, M. C.

    1990-08-01

    The lowest energy potential curves of the ArKr* exciplex are computed using non-empirical pseudopotentials and multireference configuration interaction. The {σL SSσ} states of ArKr* are obtained from relativistic averaged pseudopotentials, while the fine structure {σW} states are derived using ab initio spin-orbit pseudopotentials and achieving a diagonalisation of the total Hamiltonian(electrostatic+spin-orbit) in the basis of {σL SσS} states. The electronic structure of the exciplex is discussed and the ionic core nature of the Rydberg states is analysed.

  11. Multi-Column Experimental Test Bed for Xe/Kr Separation

    Energy Technology Data Exchange (ETDEWEB)

    Greenhalgh, Mitchell Randy [Idaho National Lab. (INL), Idaho Falls, ID (United States); Garn, Troy Gerry [Idaho National Lab. (INL), Idaho Falls, ID (United States); Welty, Amy Keil [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lyon, Kevin Lawrence [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, Tony Leroy [Idaho National Lab. (INL), Idaho Falls, ID (United States)ry

    2015-08-31

    Previous research studies have shown that INL-developed engineered form sorbents are capable of capturing both Kr and Xe from various composite gas streams. The previous experimental test bed provided single column testing for capacity evaluations over a broad temperature range. To advance research capabilities, the employment of an additional column to study selective capture of target species to provide a defined final gas composition for waste storage was warranted. The second column addition also allows for compositional analyses of the final gas product to provide for final storage determinations. The INL krypton capture system was modified by adding an additional adsorption column in order to create a multi-column test bed. The purpose of this modification was to investigate the separation of xenon from krypton supplied as a mixed gas feed. The extra column was placed in a Stirling Ultra-low Temperature Cooler, capable of controlling temperatures between 190 and 253K. Additional piping and valves were incorporated into the system to allow for a variety of flow path configurations. The new column was filled with the AgZ-PAN sorbent which was utilized as the capture medium for xenon while allowing the krypton to pass through. The xenon-free gas stream was then routed to the cryostat filled with the HZ-PAN sorbent to capture the krypton at 191K. Selectivities of xenon over krypton were determined using the new column to verify the system performance and to establish the operating conditions required for multi-column testing. Results of these evaluations verified that the system was operating as designed and also demonstrated that AgZ-PAN exhibits excellent selectivity for xenon over krypton in air at or near room temperature. Two separation tests were performed utilizing a feed gas consisting of 1000 ppmv xenon and 150 ppmv krypton with the balance being made up of air. The AgZ-PAN temperature was held at 295 or 253K while the HZ-PAN was held at 191K for both

  12. Continuous-wave high specific output power Ar-He-Xe laser with transverse RF excitation

    NARCIS (Netherlands)

    Udalov, Yu.B.; Peters, P.J.M.; Heeman-Ilieva, M.B.; Witteman, W.J.; Ochkin, V.N.

    1994-01-01

    A transverse RF excited gas discharge has been successfully used to produce a CW Ar-He-Xe laser. A maximum output power of 330 mW has been obtained from an experimental device with 37 cm active length and a 2.25 (DOT) 2.25 cm2 cross-section. This corresponds to a specific output power of about 175 m

  13. Exploring "aerogen-hydride" interactions between ZOF2 (Z = Kr, Xe) and metal hydrides: An ab initio study

    Science.gov (United States)

    Esrafili, Mehdi D.; Mohammadian-Sabet, Fariba

    2016-06-01

    In this work, a new σ-hole interaction formed between ZOF2 (Z = Kr and Xe) as the Lewis acid and a series of metal-hydrides HMX (M = Be, Mg, Zn and X = H, F, CN, CH3) is reported. The nature of this interaction, called "aerogen-hydride" interaction, is unveiled by molecular electrostatic potential, non-covalent interaction, quantum theory of atoms in molecules and natural bond orbital analyses. Our results indicate that the aerogen-hydride interactions are quite strong and can be comparable in strength to other σ-hole bonds. An important charge-transfer interaction is also associated with the formation of OF2Z⋯HMX complexes.

  14. Electronic spectra of ArXe molecules in the region of Xe* (6s', 6p, 5d), 77 000-80 200 cm{sup -1}, using resonantly enhanced multiphoton ionization

    Energy Technology Data Exchange (ETDEWEB)

    Khodorkovskii, M A; Murashov, S V [Saint-Petersburg State Polytechnical University, 195251, Saint-Petersburg (Russian Federation); Artamonova, T O; Beliaeva, A A; Rakcheeva, L P [Russian scientific center Applied Chemistry, 197198, Saint-Petersburg (Russian Federation); Pastor, A A; Serdobintsev, P Yu; Timofeev, N A; Shevkunov, I A; Dement' ev, I A [Saint-Petersburg State University, 198904, Petrodvorets (Russian Federation); Nordgren, J, E-mail: mkhodorkovskii@rscac.spb.r [Department of Physics, Fysiska Institutionen, Uppsala Universitet, Box 530, SE-751 21, Uppsala (Sweden)

    2010-08-14

    The excited electronic states of ArXe molecules in the region 77 000-80 200 cm{sup -1} were studied using the (2+1) and (3+1) resonance-enhanced multiphoton ionization methods. The use of different methods of multi-photon excitation and Ar{sup +} ion registration allowed us to obtain some new data. Molecular constants were obtained for previously unknown excited states of molecules with the following dissociation limits: ArXe* {yields} Ar{sup 1}S{sub 0}+Xe*6rcy[5/2]{sub 3} with {Omega} = 2, 3 symmetry; Ar{sup 1}S{sub 0}+Xe*6p[3/2]{sub 2} with {Omega} = 1, 2 symmetry; Xe{sup 0}S{sub 1} {yields} Xe*6s'[1/2]{sup 0}{sub 1} with {Omega} = 0{sup +} symmetry.

  15. ns2np4 (n = 4, 5) lone pair triplets whirling in M*F2E3 (M* = Kr, Xe): Stereochemistry and ab initio analyses

    Science.gov (United States)

    Galy, Jean; Matar, Samir F.

    2017-02-01

    The stereochemistry of ns2np4 (n = 4, 5) lone pair LP characterizing noble gas Kr and Xe (labeled M*) in M*F2 difluorides is examined within coherent crystal chemistry and ab initio visualizations. M*2+ in such oxidation state brings three lone pairs (E) and difluorides are formulated M*F2E3. The analyses use electron localization function (ELF) obtained within density functional theory calculations showing the development of the LP triplets whirling {E3} quantified in the relevant chemical systems. Detailed ELF data analyses allowed showing that in α KrF2E3 and isostructural XeF2E3 difluorides the three E electronic clouds merge or hybridize into a torus and adopt a perfect gyration circle with an elliptical section, while in β KrF2 the network architecture deforms the whole torus into an ellipsoid shape. Original precise metrics are provided for the torus in the different compounds under study. In KrF2 the geometric changes upon β → α phase transition is schematized and mechanisms for the transformation with temperature or pressure are proposed. The results are further highlighted by electronic band structure calculations which show similar features of equal band gaps of 3 eV in both α and β KrF2 and a reorganization of frontier orbitals due to the different orientations of the F-Kr-F linear molecule in the two tetragonal structures.

  16. Formation of KrCl * and ArCl * molecules and radiative lifetimes of their B states investigated with selective synchrotron radiation excitation

    Science.gov (United States)

    Castex, M. C.; Le Calvé, J.; Haaks, D.; Jordan, B.; Zimmerer, G.

    1980-02-01

    Monochromatic pulsed VUV excitation of Cl 2 or inert gas atoms in Cl 2 doped Kr and Ar leads to formation of KrCl * and ArCl *. The radiative lifetimes of the B states (KrCl * 19 ns, ArCl * 9 ns) and rate constants for excimer formation, quenching and collisional mixing of B and C states are given. The radiative lifetime and the quenching rate increase with vibrational excitation of the B state (KrCl *).

  17. Molecular dynamics study of the lattice thermal conductivity of Kr/Ar superlattice nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Chen Yunfei; Li Deyu; Yang Juekuan; Wu Yonghua; Lukes, J.R.; Majumdar, Arun

    2004-06-15

    The nonequilibrium molecular dynamics (NEMD) method has been used to calculate the lattice thermal conductivities of Ar and Kr/Ar nanostructures in order to study the effects of interface scattering, boundary scattering, and elastic strain on lattice thermal conductivity. Results show that interface scattering poses significant resistance to phonon transport in superlattices and superlattice nanowires. The thermal conductivity of the Kr/Ar superlattice nanowire is only about ((1)/(3)) of that for pure Ar nanowires with the same cross-sectional area and total length due to the additional interfacial thermal resistance. It is found that nanowire boundary scattering provides significant resistance to phonon transport. As the cross-sectional area increases, the nanowire boundary scattering decreases, which leads to increased nanowire thermal conductivity. The ratio of the interfacial thermal resistance to the total effective thermal resistance increases from 30% for the superlattice nanowire to 42% for the superlattice film. Period length is another important factor affecting the effective thermal conductivity of the nanostructures. Increasing the period length will lead to increased acoustic mismatch between the adjacent layers, and hence increased interfacial thermal resistance. However, if the total length of the superlattice nanowire is fixed, reducing the period length will lead to decreased effective thermal conductivity due to the increased number of interfaces. Finally, it is found that the interfacial thermal resistance decreases as the reference temperature increases, which might be due to the inelastic interface scattering.

  18. A theoretical evidence for cooperative enhancement in aerogen-bonding interactions: Open-chain clusters of KrOF2 and XeOF2

    Science.gov (United States)

    Esrafili, Mehdi D.; Vessally, Esmail

    2016-10-01

    The cooperativity of aerogen-bonding interactions is studied in open-chain (KrOF2)n=2-6 and (XeOF2)n=2-6 clusters. The formation mechanism and bonding properties of these clusters are investigated by means of molecular electrostatic potentials, natural bond orbital and noncovalent interaction index analyses. The small variation of average interaction energy from the pentamer to hexamer cluster reveals that cooperativity effects are almost completely saturated in the larger clusters. The cooperative effects in the clusters also make an increase in the average 83Kr or 129Xe chemical shielding isotropies and total spin-spin coupling constants across the aerogen-bonding.

  19. K-shell excitation by K- to L-shell charge transfer in slow Krsup(q+)-Kr and Xesup(q+)-Xe collisions

    Energy Technology Data Exchange (ETDEWEB)

    Schuch, R.; Justiniano, E.; Hoffmann, R. (Heidelberg Univ. (Germany, F.R.). Physikalisches Inst.); Schadt, W.; Schmidt-Boecking, H. (Frankfurt Univ. (Germany, F.R.). Inst. fuer Kernphysik); Mokler, P.H.; Bosch, F.; Schoenfeldt, W.A.; Stachura, Z. (Gesellschaft fuer Schwerionenforschung m.b.H., Darmstadt (Germany, F.R.))

    1983-06-14

    K vacancy production probabilities with decelerated highly-charged Krsup(q+) (2.8 MeV u/sup -1/) on Kr and Xesup(q+) (3.6 MeV u/sup -1/) on Xe were measured by particle-photon coincidences. The impact-parameter-dependent probabilities reveal a dramatic change in shape and absolute height as soon as the projectile bears L-shell vacancies. From a comparison with calculations it is concluded that K- to L-shell charge transfer can be described, even in the heavy collision system Xe on Xe, by the 2p..pi..-2psigma rotational coupling mechanism when the relativistic energy splitting is taken into account. Deviations from a statistical distribution of the projectile L vacancies between the molecular levels are found.

  20. Population inversion mechanisms producing nuclear lasing in He-3-Ar, Xe, Kr, Cl, and UF6

    Science.gov (United States)

    Deyoung, R. J.; Wilson, J. W.

    1979-01-01

    The paper examines the lasing excitation mechanisms of present nuclear lasers, with a view to developing more efficient, higher power nuclear lasers. Particular attention is given to volumetric nuclear discharges pumped by either the He-3(n, p)H-3 reaction or the U-235F6(n, ff)FF reaction. Insight gained from these laser systems will make it possible to determine the major excitation mechanisms and then to look for new gaseous laser systems where these excitation mechanisms dominate.

  1. Structure and Stability of Endohedral Complexes X@(HAlNH)12 (X = He, Ne, Ar, Kr)

    Institute of Scientific and Technical Information of China (English)

    ZHANG Cai-Yun; WU Hai-Shun

    2005-01-01

    The structures of closo-hedral cluster (HAlNH)12 and endohedral complexes X@(HAlNH)12 (X = He, Ne, Ar, Kr) have been studied by using density functional theory (DFT) at the B3LYP/6-31G(d) level. The geometries, natural bond orbital (NBO), vibrational frequency, energetic parameters, magnetic shielding constants and nucleus independent chemical shifts (NICS) were discussed. The potential surface of guest X shifting from the cage center to a face of six- membered ring was calculated at the same level. The exit transition state was demonstrated with IRC calculations. It is found that X@(HAlNH)12 complexes are dynamically stable, and Ne@(HAlNH)12 is more energetically favorable than the other complexes in thermodynamics.

  2. On the phase behavior of mixed Ar-Xe submonolayer films on graphite

    Directory of Open Access Journals (Sweden)

    A. Patrykiejew

    2012-06-01

    Full Text Available Using Monte Carlo simulation methods in the canonical and grand canonical ensembles, we discuss the melting and the formation of ordered structures of mixed Ar-Xe submonolayer films on graphite. The calculations have been performed using two- as well as three-dimensional models of the systems studied. It is demonstrated that out-of plane motion does not affect the properties of the adsorbed films as long as the total density is not close to the monolayer completion. On the other hand, close to the monolayer completion, the promotion of particles to the second layer considerably affects the properties of mixed films. It has been shown that the mixture exhibits complete mixing in the liquid phase and freezes into solid phases of the structure depending upon the film composition. For submonolayer densities, the melting temperature exhibits non-monotonous changes with the film composition. In particular, the melting temperature initially increases when the xenon concentration increases up to about 20%, then it decreases and reaches minimum for the xenon concentration of about 40%. For still higher xenon concentrations, the melting point gradually increases to the temperature corresponding to pure xenon film. It has been also demonstrated that the topology of phase diagrams of mixed films is sensitive to the composition of adsorbed layers.

  3. The mechanism of domain-wall structure formation in Ar-Kr submonolayer films on graphite

    Directory of Open Access Journals (Sweden)

    A. Patrykiejew

    2014-12-01

    Full Text Available Using Monte Carlo simulation method in the canonical ensemble, we have studied the commensurate-incommensurate transition in two-dimensional finite mixed clusters of Ar and Kr adsorbed on graphite basal plane at low temperatures. It has been demonstrated that the transition occurs when the argon concentration exceeds the value needed to cover the peripheries of the cluster. The incommensurate phase exhibits a similar domain-wall structure as observed in pure krypton films at the densities exceeding the density of a perfect (√3x√3R30º commensurate phase, but the size of commensurate domains does not change much with the cluster size. When the argon concentration increases, the composition of domain walls changes while the commensurate domains are made of pure krypton. We have constructed a simple one-dimensional Frenkel-Kontorova-like model that yields the results being in a good qualitative agreement with the Monte Carlo results obtained for two-dimensional systems.

  4. Prediction of neutral noble gas insertion compounds with heavier pnictides: FNgY (Ng = Kr and Xe; Y = As, Sb and Bi).

    Science.gov (United States)

    Ghosh, Ayan; Manna, Debashree; Ghanty, Tapan K

    2016-04-28

    A novel class of interesting insertion compounds obtained through the insertion of a noble gas atom into the heavier pnictides have been explored by various ab initio quantum chemical techniques. Recently, the first neutral noble gas insertion compounds, FXeY (Y = P, N), were theoretically predicted to be stable; the triplet state was found to be the most stable state, with a high triplet-singlet energy gap, by our group. In this study, we investigated another noble gas inserted compound, FNgY (Ng = Kr and Xe; Y = As, Sb and Bi), with a triplet ground state. Density functional theory (DFT), second order Møller-Plesset perturbation theory (MP2), coupled-cluster theory (CCSD(T)) and multi-reference configuration interaction (MRCI) based techniques have been utilized to investigate the structures, stabilities, harmonic vibrational frequencies, charge distributions and topological properties of these compounds. These predicted species, FNgY (Ng = Kr and Xe; Y = As, Sb and Bi) are found to be energetically stable with respect to all the probable 2-body and 3-body dissociation pathways, except for the 2-body channel leading to the global minimum products (FY + Ng). Nevertheless, the finite barrier height corresponding to the saddle points of the compounds connected to their respective global minima products indicates that these compounds are kinetically stable. The structural parameters, energetics, and charge distribution results as well as atoms-in-molecules (AIM) analysis suggest that these predicted molecules can be best represented as F(-)[(3)NgY](+). Thus, all the aforementioned computed results clearly indicate that it may be possible to experimentally prepare the most stable triplet state of FNgY molecules under cryogenic conditions through a matrix isolation technique.

  5. Nonplanar ion-acoustic solitons collision in Xe+-F-- SF6- and Ar+-F-- SF6- plasmas

    Science.gov (United States)

    El-Tantawy, S. A.; Carbonaro, P.

    2016-04-01

    The solitons collision in nonplanar (cylindrical and spherical) plasmas consisting of positive ions, two different negative ions, and isothermal electrons is studied. For this purpose, the Poincaré-Lighthill-Kuo (PLK) method is used to obtain two-coupled nonplanar Korteweg-de Vries (nKdV) equations. Also, the nonplanar phase shifts are calculated. The physical parameters of two plasma experiments; namely Xe+-F-- SF6- and Ar+-F-- SF6- are used to examine the properties of the localized pulses and their phase shifts after collision. It is found that the present model gives rise to the propagation of positive and negative pulses. The effects of the total negative ions concentration, the density ratio of the second-negative ions, the temperature ratio, and the geometrical effects on the behavior of solitons collisions and their phase shifts are investigated. Furthermore, it is found that the phase shifts in the case of the Ar+-F-- SF6- plasma are much larger than those of the Xe+-F-- SF6- plasma. Also, for fixed plasma parameters, the solitons collision received the largest phase shift in spherical geometry, followed by the cylindrical and planar geometries.

  6. Assignment of the /Li-7/2 optically pumped laser transitions pumped by Ar/+/ and Kr/+/ laser lines

    Science.gov (United States)

    Verma, K. K.; Stwalley, W. C.; Zemke, W. T.

    1981-01-01

    Welling and Wellegehausen (1977) have reported a list of Na2 and Li2 lines (belonging to B-X and A-X systems) which lase when vapors of these dimers are pumped with an Ar(+) or Kr(+) laser. A description is presented of a fluorescence study of the A-X system of the (Li-7)2 molecule excited by a Kr(+) laser (6471 A). The optically pumped laser lines are identified as P and R doublets in two different fluorescence series. The conditions which favor lasing action of these lines are pointed out. All but one of the known optically pumped laser lines of (Li-7)2 along with their assignments are presented in a table. For each pumping line, several additional wavelengths are listed which satisfy the condition for laser oscillations and which might well lase well under slightly improved conditions.

  7. Study of x-rays produced from debris-free sources with Ar, Kr and Kr/Ar mixture linear gas jets irradiated by UNR Leopard laser beam with fs and ns pulse duration

    Science.gov (United States)

    Kantsyrev, V. L.; Schultz, K. A.; Shlyaptseva, V. V.; Safronova, A. S.; Shrestha, I. K.; Petrov, G. M.; Moschella, J. J.; Petkov, E. E.; Stafford, A.; Cooper, M. C.; Weller, M. E.; Cline, W.; Wiewior, P.; Chalyy, O.

    2016-06-01

    Experiments of x-ray emission from Ar, Kr, and Ar/Kr gas jet mixture were performed at the UNR Leopard Laser Facility operated with 350 fs pulses at laser intensity of 2 × 1019 W/cm2 and 0.8 ns pulses at an intensity of 1016 W/cm2. Debris free x-ray source with supersonic linear nozzle generated clusters/monomer jet with an average density of ≥1019 cm-3 was compared to cylindrical tube subsonic nozzle, which produced only monomer jet with average density 1.5-2 times higher. The linear (elongated) cluster/gas jet provides the capability to study x-ray yield anisotropy and laser beam self-focusing with plasma channel formation that are interconnecting with efficient x-ray generation. Diagnostics include x-ray diodes, pinhole cameras and spectrometers. It was observed that the emission in the 1-9 keV spectral region was strongly anisotropic depending on the directions of laser beam polarization for sub-ps laser pulse and supersonic linear jet. The energy yield in the 1-3 keV region produced by a linear nozzle was an order of magnitude higher than from a tube nozzle. Non-LTE models and 3D molecular dynamic simulations of Ar and Kr clusters irradiated by sub-ps laser pulses have been implemented to analyze obtained data. A potential evidence of electron beam generation in jets' plasma was discussed. Note that the described debris-free gas-puff x-ray source can generate x-ray pulses in a high repetition regime. This is a great advantage compared to solid laser targets.

  8. Atomic alignment effect on reactivity and on product alignment in the energy-transfer reaction of oriented Ar (3P2, 4s [3/2]2, M(J) = 2) + Kr (4p6, 1S0) → Ar (3p6, 1S0) + Kr (5p [3/2]2).

    Science.gov (United States)

    Ohoyama, H

    2015-03-12

    Steric effect for the formation of Kr (5p [3/2]₂) in the energy transfer reaction of Ar (³P₂, 4s [3/2]₂) + Kr has been studied by using an oriented Ar (³P₂, 4s [3/2]₂, M(J) = 2) beam at a collision energy of ∼0.09 eV. The emission intensity of Kr (5p [3/2]₂) is ca. 2 times enhanced when the angular momentum (J(Ar)) of Ar (³P₂) is aligned perpendicular to the relative velocity vector (v(R)). In addition, the Kr (5p [3/2]₂) emission is highly polarized parallel to v(R) (I(∥)/I(⊥) ∼ 1.2) when JAr is aligned perpendicular to v(R). The observed polarization moments indicate that the alignment of the unpaired Ar (3p) orbital of Ar (³P₂) to v(R), (Σ (|L′| = 0), Π (|L′| = 1)), dominates the energy transfer probability (σ(Π)(∥): σ(Σ)(∥): σ(Π)(⊥): σ(Σ)(⊥) = 0.49:1.33:0.55:1.23) and also the alignment of the Kr (5p) orbital of Kr (5p [3/2]₂) to v(R): the Σ-configuration of the Ar (3p) orbital leads to the parallel alignment (Σ-configuration) of the Kr(5p) orbital to v(R), conversely, the Π-configuration of Ar (3p) orbital leads to the perpendicular alignment (Π-configuration) of the Kr(5p) orbital. In addition, the selectivity of the alignment of the Kr (5p) orbital turns out to vary from perpendicular to parallel as the collision energy increases after a threshold down to 0.03 eV.

  9. Theoretical investigation of the dihydrogen bond linking MH2 with HCCRgF (M = Zn, Cd; Rg = Ar, Kr).

    Science.gov (United States)

    Solimannejad, Mohammad; Scheiner, Steve

    2005-12-29

    An ab initio computational study of the properties of four linear dihydrogen-bonded complexes pairing MH2 (M = Zn, Cd) with HCCRgF (Rg = Ar, Kr) was undertaken at the MP2/DGDZVP level of theory. The calculated complexation energies of the linear complexes vary between 6.5 kJ/mol for M = Zn to 8.5 kJ/mol for M = Cd. Equilibrium interatomic H...H distances are roughly 2.07 A for all four complexes. The red shifts of the H-C stretching frequency of HCCRgF correlate nicely with the interaction energies.

  10. Absorption by XeCl* excimer molecules of their own emission of the B-X transition (λ = 308 nm) in a dense Ar-Xe-CCl4 medium upon pumping by fast electrons and uranium-235 fission fragments

    Science.gov (United States)

    Mis'kevich, A. I.; Dyuzhov, Yu. A.; Suvorov, A. A.

    2016-08-01

    Luminescence of dense Ar-Xe-CCl4 gas mixtures with a low CCl4 content upon pumping by fast electrons and uranium-235 fission fragments is studied by spectroscopic methods. It is found that, in a cell with a resonator tuned to the B-X transition of the XeCl* molecule (λ = 308 nm), the D-state population of the XeCl* excimer molecule (the D-X transition, λ = 235 nm) depends on the B-state population and increases by many times with increasing B-state population of the XeCl* molecule. The stimulated absorption coefficient k = 1.2 × 10-16 of B-X transition emission of the XeCl* molecule (λmax = 308 nm), which leads to population of the D-state of this molecule, and the coefficient of amplification μ = 2.5 × 10-4 cm-1 of B-X transition emission of the Xe Cl* molecule (λ = 308 nm) are measured upon pumping by uranium- 235 fission fragments with the specific energy input into the gas medium of ~60 mJ/cm3 and a specific power of energy input of about 240 W/cm3.

  11. Development of Xe and Kr empirical potentials for CeO2, ThO2, UO2 and PuO2, combining DFT with high temperature MD

    Science.gov (United States)

    Cooper, M. W. D.; Kuganathan, N.; Burr, P. A.; Rushton, M. J. D.; Grimes, R. W.; Stanek, C. R.; Andersson, D. A.

    2016-10-01

    The development of embedded atom method (EAM) many-body potentials for actinide oxides and associated mixed oxide (MOX) systems has motivated the development of a complementary parameter set for gas-actinide and gas-oxygen interactions. A comprehensive set of density functional theory (DFT) calculations were used to study Xe and Kr incorporation at a number of sites in CeO2, ThO2, UO2 and PuO2. These structures were used to fit a potential, which was used to generate molecular dynamics (MD) configurations incorporating Xe and Kr at 300 K, 1500 K, 3000 K and 5000 K. Subsequent matching to the forces predicted by DFT for these MD configurations was used to refine the potential set. This fitting approach ensured weighted fitting to configurations that are thermodynamically significant over a broad temperature range, while avoiding computationally expensive DFT-MD calculations. The resultant gas potentials were validated against DFT trapping energies and are suitable for simulating combinations of Xe and Kr in solid solutions of CeO2, ThO2, UO2 and PuO2, providing a powerful tool for the atomistic simulation of conventional nuclear reactor fuel UO2 as well as advanced MOX fuels.

  12. Development of Xe and Kr empirical potentials for CeO2, ThO2, UO2 and PuO2, combining DFT with high temperature MD.

    Science.gov (United States)

    Cooper, M W D; Kuganathan, N; Burr, P A; Rushton, M J D; Grimes, R W; Stanek, C R; Andersson, D A

    2016-10-12

    The development of embedded atom method (EAM) many-body potentials for actinide oxides and associated mixed oxide (MOX) systems has motivated the development of a complementary parameter set for gas-actinide and gas-oxygen interactions. A comprehensive set of density functional theory (DFT) calculations were used to study Xe and Kr incorporation at a number of sites in CeO2, ThO2, UO2 and PuO2. These structures were used to fit a potential, which was used to generate molecular dynamics (MD) configurations incorporating Xe and Kr at 300 K, 1500 K, 3000 K and 5000 K. Subsequent matching to the forces predicted by DFT for these MD configurations was used to refine the potential set. This fitting approach ensured weighted fitting to configurations that are thermodynamically significant over a broad temperature range, while avoiding computationally expensive DFT-MD calculations. The resultant gas potentials were validated against DFT trapping energies and are suitable for simulating combinations of Xe and Kr in solid solutions of CeO2, ThO2, UO2 and PuO2, providing a powerful tool for the atomistic simulation of conventional nuclear reactor fuel UO2 as well as advanced MOX fuels.

  13. Atomic data for neutron-capture elements III. Charge transfer rate coefficients for low-charge ions of Ge, Se, Br, Kr, Rb, and Xe

    CERN Document Server

    Sterling, N C

    2011-01-01

    We present total and final-state resolved charge transfer (CT) rate coefficients for low-charge Ge, Se, Br, Kr, Rb, and Xe ions reacting with neutral hydrogen over the temperature range 10^2--10^6 K. Each of these elements has been detected in ionized astrophysical nebulae, particularly planetary nebulae. CT rate coefficients are a key ingredient for the ionization equilibrium solutions needed to determine total elemental abundances from those of the observed ions. A multi-channel Landau Zener approach was used to compute rate coefficients for projectile ions with charges q=2-5, and for singly-charged ions the Demkov approximation was utilized. Our results for five-times ionized species are lower limits, due to the incompleteness of level energies in the NIST database. In addition, we computed rate coefficients for charge transfer ionization reactions between the neutral species of the above six elements and ionized hydrogen. The resulting total and state-resolved CT rate coefficients are tabulated and availa...

  14. Correlation consistent valence basis sets for use with the Stuttgart-Dresden-Bonn relativistic effective core potentials the atoms Ga-Kr and In-Xe

    CERN Document Server

    Martin, J M L; Martin, Jan M.L.; Sundermann, Andreas

    2001-01-01

    We propose large-core correlation-consistent pseudopotential basis sets for the heavy p-block elements Ga-Kr and In-Xe. The basis sets are of cc-pVTZ and cc-pVQZ quality, and have been optimized for use with the large-core (valence-electrons only) Stuttgart-Dresden-Bonn relativistic pseudopotentials. Validation calculations on a variety of third-row and fourth-row diatomics suggest them to be comparable in quality to the all-electron cc-pVTZ and cc-pVQZ basis sets for lighter elements. Especially the SDB-cc-pVQZ basis set in conjunction with a core polarization potential (CPP) yields excellent agreement with experiment for compounds of the later heavy p-block elements. For accurate calculations on Ga (and, to a lesser extent, Ge) compounds, explicit treatment of 13 valence electrons appears to be desirable, while it seems inevitable for In compounds. For Ga and Ge, we propose correlation consistent basis sets extended for (3d) correlation. For accurate calculations on organometallic complexes of interest to h...

  15. Electronic spectra of ArXe molecules in the region of Xe* (5d, 7s, 7p, 6p'), 80 300-89 500 cm{sup -1}, using resonantly enhanced multiphoton ionization

    Energy Technology Data Exchange (ETDEWEB)

    Khodorkovskii, M A; Murashov, S V [Saint Petersburg State Polytechnical University, 195251, Saint Petersburg (Russian Federation); Artamonova, T O; Beliaeva, A A; Rakcheeva, L P [Russian Scientific Center ' Applied Chemistry' , 197198, Saint Petersburg (Russian Federation); Pastor, A A; Serdobintsev, P Yu; Timofeev, N A; Shevkunov, I A; Dement' ev, I A [Saint Petersburg State University, 198904, Petrodvorets (Russian Federation); Nordgren, J, E-mail: mkhodorkovskii@rscac.spb.r [Department of Physics, Uppsala Universitet, Fysiska Institutionen, Box 530, SE-751 21, Uppsala (Sweden)

    2010-12-14

    The electronic spectra of ArXe molecules in the 80 300-89 500 cm{sup -1} region were recorded by (2 + n) and (3 + n) REMPI methods. The vibrational progressions attributed to transitions of molecules from the ground state to the bounded excited state and wide unstructured bands related to transitions to the continuous upper state were obtained. The molecular constants of ArXe* were calculated for all the observed progressions in the 80 300-87 000 cm{sup -1} region as an approximation of an anharmonic oscillator and the Morse potential. For different excited states the energy of harmonic oscillator and the dissociation energy are changed from 10 to 100 cm{sup -1} and from 70 to 750 cm{sup -1}, respectively.

  16. Hyperfine frequencies of 87Rb and 133Cs atoms in Xe gas

    CERN Document Server

    McGuyer, B H; Happer, W; 10.1103/PhysRevA.84.030501

    2013-01-01

    The microwave resonant frequencies of ground-state 87Rb and 133Cs atoms in Xe buffer gas are shown to have a relatively large nonlinear dependence on the Xe pressure, presumably because of RbXe or CsXe van der Waals molecules. The nonlinear shifts for Xe are opposite in sign to the previously measured shifts for Ar and Kr, even though all three gases have negative linear shifts. The Xe data show striking discrepancies with the previous theory for nonlinear shifts. Most of this discrepancy is eliminated by accounting for the spin-rotation interaction in addition to the hyperfine-shift interaction in the molecules. To the limit of our experimental accuracy, the shifts of 87Rb and 133Cs in He, Ne, and N2 were linear with pressure.

  17. Electron scattering by Ne, Ar and Kr at intermediate and high energies, 0.5-10 keV

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, G.; Roteta, M.; Manero, F. [Centro de Investigaciones Energeticas Medioambientales y Tecnologicas (CIEMAT), Departamento de Fusion y Particulas Elementales, Madrid (Spain); Blanco, F. [Universidad Complutense de Madrid, Facultad de Fisica, Departamento de Fisica Atomica Molecular y Nuclear, Madrid (Spain); Williart, A. [Universidad Nacional de Educacion a Distancia, Facultad de Ciencias, Departamento de Fisica de los Materiales, Madrid (Spain)

    1999-04-28

    Semi-empirical total cross sections for electron scattering of noble gases (Ne, Ar and Kr) in the energy range 0.5-10 keV have been obtained by combining transmission-beam measurements for impact energies up to 6 keV with an asymptotic behaviour at higher energies according to the Born-Bethe approximation. The influence of the forward electron scattering on the experimental system has been evaluated by means of a Monte Carlo electron transport simulation. Theoretical values have also been obtained by applying the Born approximation in the case of inelastic processes and by means of an atomic scattering potential for the elastic part. The results of these calculations show an excellent agreement with the semi-empirical values in the above-mentioned energy range. (author)

  18. Physisorption of Ar, Kr, CH4, and N2 on 304 stainless steel at very low pressures.

    Science.gov (United States)

    Troy, M.; Wightman, J. P.

    1971-01-01

    Determination of physisorption isotherms of these gases on stainless steel by pressure change measurements in very low pressure cryogenic baths where a steel nipple was brought in contact with the test gas at 77 to 90 K in a sealed constant-volume system. The position of the nipple in the gas was changed in such a manner that gas adsorption on a 47.5 sq cm area of the steel surface could be measured. The Dubinin-Radushkevich (DR) equation (1947) was used for an empirical description of isotherms at different temperatures. The mean adsorption energies calculated from the DR plots were 1290, 1545, 1490 and 1903 cal/mol for Ar, Kr, CH4 and N2, respectively, being about 10% higher than the corresponding values on Pyrex.

  19. Resonant third harmonic generation of KrF laser in Ar gas

    Energy Technology Data Exchange (ETDEWEB)

    Rakowski, R. [Department of Experimental Physics, University of Szeged, 6720 Szeged, Dóm tér 9 (Hungary); Institute of Optoelectronics, Military University of Technology, Gen. S. Kaliskiego 2, 00–908 Warsaw (Poland); Barna, A. [Department of Experimental Physics, University of Szeged, 6720 Szeged, Dóm tér 9 (Hungary); Wigner Research Centre for Physics, Institute for Particle and Nuclear Physics, EURATOM Association HAS, 1121 Budapest, XII. Konkoly Thege Miklós út 29-33 (Hungary); Suta, T.; Földes, I. B. [Wigner Research Centre for Physics, Institute for Particle and Nuclear Physics, EURATOM Association HAS, 1121 Budapest, XII. Konkoly Thege Miklós út 29-33 (Hungary); Bohus, J.; Szatmári, S. [Department of Experimental Physics, University of Szeged, 6720 Szeged, Dóm tér 9 (Hungary); Mikołajczyk, J.; Bartnik, A.; Fiedorowicz, H. [Institute of Optoelectronics, Military University of Technology, Gen. S. Kaliskiego 2, 00–908 Warsaw (Poland); Verona, C. [Department of Mechanical Engineering, University “Tor Vergata”, Via Orazio Raimondo, 18–00173, Rome (Italy); Verona Rinati, G. [Department of Industrial Engineering, University “Tor Vergata”, Via Orazio Raimondo, 18–00173, Rome (Italy); Margarone, D. [Institute of Physics ASCR, v.v.i. (FZU), ELI-Beamlines Project, 182 21 Prague (Czech Republic); Nowak, T. [Institute of Nuclear Physics, PAN, E. Radzikowskiego 152, 31–342 Cracow (Poland); and others

    2014-12-15

    Investigations of emission of harmonics from argon gas jet irradiated by 700 fs, 5 mJ pulses from a KrF laser are presented. Harmonics conversion was optimized by varying the experimental geometry and the nozzle size. For the collection of the harmonic radiation silicon and solar-blind diamond semiconductor detectors equipped with charge preamplifiers were applied. The possibility of using a single-crystal CVD diamond detector for separate measurement of the 3rd harmonic in the presence of a strong pumping radiation was explored. Our experiments show that the earlier suggested 0.7% conversion efficiency can really be obtained, but only in the case when phase matching is optimized with an elongated gas target length corresponding to the length of coherence.

  20. Results of experiments devoted to searches for 2 K capture on 78Kr and for the double-beta decay of 136Xe with the aid of proportional counters

    Science.gov (United States)

    Gavrilyuk, Yu. M.; Gangapshev, A. M.; Zhantudueva, Dj. A.; Kazalov, V. V.; Kuz'minov, V. V.; Panasenko, S. I.; Ratkevich, S. S.; Efendiev, K. V.; Yakimenko, S. P.

    2013-09-01

    A brief description of two low-background setups deployed at the Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences) and intended for searches for two types of double-beta decay of inert-gas isotopes—2 K capture on 78Kr and the double-beta decay of 136Xe—is given. The two setups in question have similar structures and employ identical large high-pressure copper proportional counters as detectors. Upon a treatment of data from measurements with krypton samples differing in the content of the isotope 78Kr, the spectrum for an enriched sample revealed an excess of events at a statistical-significance level of about two standard deviations (2 σ). If one attributes this excess to 2 K(2 ν) capture on 78Kr, the respective half-life is T 1/2 = 1.4{-0.7/+2.3} × 1022 yr at a 90% C.L. A treatment of data from measurements with xenon samples differing in content of the isotope 136Xe led to the appearance of an excess of events in the spectrum for an enriched sample at a statistical-significance level of about 2.2 σ. If one assumes that this excess is due to the two-neutrino double-beta decay of 136Xe, then the respective half-life is T 1/2 = 5.8{-1.8/+4.7} × 1021 yr.

  1. Test beam studies of the TRD prototype filled with different gas mixtures based on Xe, Kr, and Ar

    Science.gov (United States)

    Celebi, E.; Brooks, T.; Joos, M.; Rembser, C.; Gurbuz, S.; Cetin, S. A.; Konovalov, S. P.; Tikhomirov, V. O.; Zhukov, K.; Fillipov, K. A.; Romaniouk, A.; Smirnov, S. Yu; Teterin, P. E.; Vorobev, K. A.; Boldyrev, A. S.; Maevsky, A.; Derendarz, D.

    2017-01-01

    Towards the end of LHC Run1, gas leaks were observed in some parts of the Transition Radiation Tracker (TRT) of ATLAS. Due to these leaks, primary Xenon based gas mixture was replaced with Argon based mixture in various parts. Test-beam studies with a dedicated Transition Radiation Detector (TRD) prototype were carried out in 2015 in order to understand transition radiation performance with mixtures based on Argon and Krypton. We present and discuss the results of these test-beam studies with different active gas compositions.

  2. Photoionization pathways and thresholds in generation of Lyman-α radiation by resonant four-wave mixing in Kr-Ar mixture

    OpenAIRE

    Oleg A. Louchev; Norihito Saito; Yu Oishi; Koji Miyazaki; Kotaro Okamura; Jumpei Nakamura; Masahiko Iwasaki; Satoshi Wada

    2016-01-01

    We develop a set of analytical approximations for the estimation of the combined effect of various photoionization processes involved in the resonant four-wave mixing generation of ns pulsed Lyman-α (L-α) radiation by using 212.556 nm and 820-845 nm laser radiation pulses in Kr-Ar mixture: (i) multi-photon ionization, (ii) step-wise (2+1)-photon ionization via the resonant 2-photon excitation of Kr followed by 1-photon ionization and (iii) laser-induced avalanche ionization produced by genera...

  3. Crystallographic Studies of Xe And Kr Binding Within the Large Internal Cavity of Cytochrome Ba(3) From Thermus Thermophilus: Structural Analysis And Role of Oxygen Transport Channels in the Heme-Cu Oxidases

    Energy Technology Data Exchange (ETDEWEB)

    Luna, V.M.; Chen, Y.; Fee, J.A.; Stout, C.D.

    2009-05-26

    Cytochrome ba{sub 3} is a cytochrome c oxidase from the plasma membrane of Thermus thermophilus and is the preferred terminal enzyme of cellular respiration at low dioxygen tensions. Using cytochrome ba{sub 3} crystals pressurized at varying conditions under Xe or Kr gas, and X-ray data for six crystals, we identify the relative affinities of Xe and Kr atoms for as many as seven distinct binding sites. These sites track a continuous, Y-shaped channel, 18--20 {angstrom} in length, lined by hydrophobic residues, which leads from the surface of the protein where two entrance holes, representing the top of the Y, connect the bilayer to the {alpha}{sub 3}-Cu{sub B} center at the base of the Y. Considering the increased affinity of O{sub 2} for hydrophobic environments, the hydrophobic nature of the channel, its orientation within the bilayer, its connection to the active site, its uniform diameter, its virtually complete occupation by Xe, and its isomorphous presence in the native enzyme, we infer that the channel is a diffusion pathway for O{sub 2} into the dinuclear center of cytochrome ba{sub 3}. These observations provide a basis for analyzing similar channels in other oxidases of known structure, and these structures are discussed in terms of mechanisms of O{sub 2} transport in biological systems, details of CO binding to and egress from the dinuclear center, the bifurcation of the oxygen-in and water-out pathways, and the possible role of the oxygen channel in aerobic thermophily.

  4. Photoionization-induced π↔ H site switching dynamics in phenol(+)-Rg (Rg = Ar, Kr) dimers probed by picosecond time-resolved infrared spectroscopy.

    Science.gov (United States)

    Miyazaki, Mitsuhiko; Sakata, Yuri; Schütz, Markus; Dopfer, Otto; Fujii, Masaaki

    2016-09-21

    The ionization-induced π↔ H site switching reaction in phenol(+)-Rg (PhOH(+)-Rg) dimers with Rg = Ar and Kr is traced in real time by picosecond time-resolved infrared (ps-TRIR) spectroscopy. The ps-TRIR spectra show the prompt appearance of the non-vanishing free OH stretching band upon resonant photoionization of the π-bound neutral clusters, and the delayed appearance of the hydrogen-bonded (H-bonded) OH stretching band. This result directly proves that the Rg ligand switches from the π-bound site on the aromatic ring to the H-bonded site at the OH group by ionization. The subsequent H →π back reaction converges the dimer to a π↔ H equilibrium. This result is in sharp contrast to the single-step π→ H forward reaction in the PhOH(+)-Ar2 trimer with 100% yield. The reaction mechanism and yield strongly depend on intracluster vibrational energy redistribution. A classical rate equation analysis for the time evolutions of the band intensities of the two vibrations results in similar estimates for the time constants of the π→ H forward reaction of τ+ = 122 and 73 ps and the H →π back reaction of τ- = 155 and 188 ps for PhOH(+)-Ar and PhOH(+)-Kr, respectively. The one order of magnitude slower time constant in comparison to the PhOH(+)-Ar2 trimer (τ+ = 7 ps) is attributed to the decrease in density of states due to the absence of the second Ar in the dimer. The similar time constants for both PhOH(+)-Rg dimers are well rationalized by a classical interpretation based on the comparable potential energy surfaces, reaction pathways, and density of states arising from their similar intermolecular vibrational frequencies.

  5. Coherence of Auger and inter-Coulombic decay processes in the photoionization of Ar@C60 versus Kr@C60

    CERN Document Server

    Magrakvelidze, Maia; Javani, Mohammad H; Madjet, Mohamed E; Manson, Steven T; Chakraborty, Himadri S

    2015-01-01

    For the asymmetric spherical dimer of an endohedrally confined atom and a host fullerene, an innershell vacancy of either system can decay through the continuum of an outer electron hybridized between the systems. Such decays, viewed as coherent superpositions of the single-center Auger and two-center inter-Coulombic (ICD) amplitudes, are found to govern leading decay mechanisms in noble-gas endofullerenes, and are likely omnipresent in this class of nanomolecules. A comparison between resulting autoionizing resonances calculated in the photoionization of Ar@C60 and Kr@C60 exhibits details of the underlying processes.

  6. High-efficiency generation of pulsed Lyman-α radiation by resonant laser wave mixing in low pressure Kr-Ar mixture.

    Science.gov (United States)

    Saito, Norihito; Oishi, Yu; Miyazaki, Koji; Okamura, Kotaro; Nakamura, Jumpei; Louchev, Oleg A; Iwasaki, Masahiko; Wada, Satoshi

    2016-04-04

    We report an experimental generation of ns pulsed 121.568 nm Lyman-α radiation by the resonant nonlinear four-wave mixing of 212.556 nm and 845.015 nm radiation pulses providing a high conversion efficiency 1.7x10-3 with the output pulse energy 3.6 μJ achieved using a low pressure Kr-Ar mixture. Theoretical analysis shows that this efficiency is achieved due to the advantage of using (i) the high input laser intensities in combination with (ii) the low gas pressure allowing us to avoid the onset of full-scale discharge in the laser focus. In particular, under our experimental conditions the main mechanism of photoionization caused by the resonant 2-photon 212.556 nm radiation excitation of Kr atoms followed by the 1-photon ionization leads to ≈17% loss of Kr atoms and efficiency loss only by the end of the pulse. The energy of free electrons, generated by 212.556 nm radiation via (2 + 1)-photon ionization and accelerated mainly by 845.015 nm radiation, remains during the pulse below the level sufficient for the onset of full-scale discharge by the electron avalanche. Our analysis also suggests that ≈30-fold increase of 845.015 nm pulse energy can allow one to scale up the L-α radiation pulse energy towards the level of ≈100 μJ.

  7. Search for a particle dependency of IR- and UV-emissions of a liquid Ar-Xe-mixture for a novel detector concept

    Energy Technology Data Exchange (ETDEWEB)

    Himpsl, Andreas; Ulrich, Andreas [Physik-Department E12, Technische Universitaet Muenchen, James-Franck-Strasse 1, 85748 Garching (Germany); Neumeier, Alexander [Physik-Department E15, Technische Universitaet Muenchen, James-Franck-Strasse 1, 85748 Garching (Germany)

    2015-07-01

    An approach to a novel particle detector concept based on liquid rare gas mixtures is presented. The newly found emissions of a liquid Ar-Xe-mixture consists of two intense peaks in the IR and VUV, respectively, separated by 800 nm, more than the whole visible spectral range. Due to the intrinsic detector responsivities, it is possible to use different detectors to obtain two independent scintillation signals on a pure optical basis. The goal of this work is the search for a particle dependency of the intensity ratios or the time structure of both emissions. The experiments will be carried out at the tandem accelerator of the Maier-Leibnitz-Laboratorium in Garching, using different particle beams at low energy and current.

  8. Study of laser-generated debris free x-ray sources produced in a high-density linear Ar, Kr, Xe, Kr/Ar and Xe/Kr/Ar mixtures gas jets by 2 ω, sub-ps LLNL Titan laser

    Science.gov (United States)

    Kantsyrev, V. L.; Schultz, K. A.; Shlyaptseva, V. V.; Safronova, A. S.; Cooper, M. C.; Shrestha, I. K.; Petkov, E. E.; Stafford, A.; Moschella, J. J.; Schmidt-Petersen, M. T.; Butcher, C. J.; Kemp, G. E.; Andrews, S. D.; Fournier, K. B.

    2016-10-01

    The study of laser-generated debris-free x-ray sources in an underdense plasma produced in a high-density linear gas-puff jet was carried out at the LLNL Titan laser (2 ω, 45 J, sub-ps) with an intensity in the 10 um focal spot of 7 x 1019 W/cm2. A linear nozzle with a fast valve was used for the generation of a clusters/gas jet. X-ray diagnostics for the spectral region of 0.7 - 9 keV include: two spectrometers and pinhole cameras, and 3 groups of fast filtered detectors. Electron beams were measured with the EPPS magnetic spectrometer (>1 MeV) and Faraday cups (>72 keV). Spectralon/spectrometer devices were also used to measure absorption of laser radiation in the jets. New results were obtained on: anisotropic generation of x-rays (laser to x-ray conversion coefficient was >1%) and characteristics of laser-generated electron beams; evolution of x-ray generation with the location of the laser focus in a cluster-gas jet, and observations of a strong x-ray flash in some focusing regimes. Non-LTE kinetic modeling was used to estimate plasma parameters. UNR work supported by the DTRA Basic Research Award # HDTRA1-13-1-0033. Work at LLNL was performed under the auspices of the U.S. DOE by LLNL under Contract DE-AC52-07NA27344.

  9. Photoionization pathways and thresholds in generation of Lyman-α radiation by resonant four-wave mixing in Kr-Ar mixture

    Science.gov (United States)

    Louchev, Oleg A.; Saito, Norihito; Oishi, Yu; Miyazaki, Koji; Okamura, Kotaro; Nakamura, Jumpei; Iwasaki, Masahiko; Wada, Satoshi

    2016-09-01

    We develop a set of analytical approximations for the estimation of the combined effect of various photoionization processes involved in the resonant four-wave mixing generation of ns pulsed Lyman-α (L-α ) radiation by using 212.556 nm and 820-845 nm laser radiation pulses in Kr-Ar mixture: (i) multi-photon ionization, (ii) step-wise (2+1)-photon ionization via the resonant 2-photon excitation of Kr followed by 1-photon ionization and (iii) laser-induced avalanche ionization produced by generated free electrons. Developed expressions validated by order of magnitude estimations and available experimental data allow us to identify the area for the operation under high input laser intensities avoiding the onset of full-scale discharge, loss of efficiency and inhibition of generated L-α radiation. Calculations made reveal an opportunity for scaling up the output energy of the experimentally generated pulsed L-α radiation without significant enhancement of photoionization.

  10. Photoionization pathways and thresholds in generation of Lyman-α radiation by resonant four-wave mixing in Kr-Ar mixture

    Directory of Open Access Journals (Sweden)

    Oleg A. Louchev

    2016-09-01

    Full Text Available We develop a set of analytical approximations for the estimation of the combined effect of various photoionization processes involved in the resonant four-wave mixing generation of ns pulsed Lyman-α (L-α radiation by using 212.556 nm and 820-845 nm laser radiation pulses in Kr-Ar mixture: (i multi-photon ionization, (ii step-wise (2+1-photon ionization via the resonant 2-photon excitation of Kr followed by 1-photon ionization and (iii laser-induced avalanche ionization produced by generated free electrons. Developed expressions validated by order of magnitude estimations and available experimental data allow us to identify the area for the operation under high input laser intensities avoiding the onset of full-scale discharge, loss of efficiency and inhibition of generated L-α radiation. Calculations made reveal an opportunity for scaling up the output energy of the experimentally generated pulsed L-α radiation without significant enhancement of photoionization.

  11. Total and elastic electron scattering cross sections from Xe at intermediate and high energies

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, G [Instituto de Matematicas y Fisica Fundamental, CSIC, Serrano 123, 28006 Madrid (Spain); Pablos, J L de [Departamento de Fusion y Particulas Elementales, CIEMAT, Avenida Complutense 22, 28040 Madrid (Spain); Blanco, F [Departamento de Fisica Atomica Molecular y Nuclear, Universidad Complutense de Madrid, 28040 Madrid (Spain); Williart, A [Departamento de Fisica de los Materiales, UNED, Senda del Rey 9, 28040 Madrid (Spain)

    2002-11-28

    Experimental total electron scattering cross sections from Xe in the energy range 300-5000 eV have been obtained with experimental errors of about 3%. The method was based on the measurement of the attenuation of a linear electron beam through a Xe gas cell in combination with an electron spectroscopy technique to analyse the energy of the transmitted electrons. Differential and integral elastic cross sections have been calculated using a scattering potential method which includes relativistic effects. The consistency of our theoretical and experimental results is also discussed in the paper. Finally, analytical formulae depending on two parameters, namely the number of target electrons and the atomic polarizability, are given to reproduce the experimental data for Ne, Ar, Kr and Xe in the energy range 500-10 000 eV.

  12. Xe anions in stable Mg-Xe compounds: the mechanism of missing Xe in earth atmosphere

    CERN Document Server

    Miao, Mao-sheng

    2013-01-01

    The reactivity of noble gas elements is important for both fundamental chemistry and geological science. The discovery of the oxidation of Xe extended the doctrinal boundary of chemistry that a complete shell is inert to reaction. The oxidations of Xe by various geological substances have been researched in order to explain the missing Xe in earth atmosphere. Among many proposals, the chemistry mechanisms are straightforward as they identify chemical processes that can capture Xe in earth interior. However, all the mechanisms based on current noble gas chemistry face the same difficulty: the earth lower mantle and core are rich in metals and therefore their chemical environment is reductive. On the other hand, up till now, the opposite chemical inclination, the reductive propensity, i.e. gaining electrons and forming anions, has not been proposed and examined for noble gas elements. In this work, we demonstrate, using first principles calculations and an efficient structure prediction method, that Xe and Kr c...

  13. Probing the photochemistry of chemisorbed oxygen on TiO2(110) with Kr and other co-adsorbates

    Energy Technology Data Exchange (ETDEWEB)

    Petrik, Nikolay G.; Kimmel, Gregory A.

    2014-02-14

    Weakly bound (physisorbed) atoms and molecules such as Ar, Kr, Xe, CO, CH4, CH3OH, CO2 and N2 are used to probe the photochemical interactions of O2 on rutile TiO2(110). UV irradiation of chemisorbed O2 along with the physisorbed probe species leads to photon-stimulated desorption (PSD) of Ar, Kr, CO, CH4 and N2. Without co-adsorbed O2, the PSD yields of the probe species are very low or not observed. No PSD was observed for CO2, N2O, CH3OH and the PSD yield for Xe is very low compared to the other probe atoms or molecules. The angular distribution of the photo-desorbing Kr, which is broad and cosine, is quite different from the O2 PSD angular distribution, which is sharply peaked along the surface normal. The Kr PSD yields increase with increasing coverage of Kr and of chemisorbed O2. We propose a mechanism for the observed phenomena where the chemisorbed O2 serves as photoactive center, excited via electronic excitations (electrons and/or holes) created in the TiO2 substrate by UV photon irradiation. The photo-excited O2 may transfer its energy to neighboring co-adsorbed atom or molecule resulting in desorption of the latter. Simple momentum transfer considerations suggest that heavier adsorbates (like Xe) and adsorbates with higher binding energy (like CO2) should desorb less efficiently according to the proposed mechanism. Various forms of chemisorbed O2 appeared photoactive in such stimulated desorption of Kr atoms: molecular anions (O22-, O2-), adatoms (Oa), and others. The observed phenomenon provides a new tool for study of photocatalysis.

  14. Mechanism and computational model for Lyman-{alpha}-radiation generation by high-intensity-laser four-wave mixing in Kr-Ar gas

    Energy Technology Data Exchange (ETDEWEB)

    Louchev, Oleg A.; Saito, Norihito; Wada, Satoshi [Advanced Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Bakule, Pavel [STFC, ISIS Facility, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX (United Kingdom); Yokoyama, Koji [Advanced Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Advanced Meson Science Laboratory, RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan); Ishida, Katsuhiko; Iwasaki, Masahiko [Advanced Meson Science Laboratory, RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan)

    2011-09-15

    We present a theoretical model combined with a computational study of a laser four-wave mixing process under optical discharge in which the non-steady-state four-wave amplitude equations are integrated with the kinetic equations of initial optical discharge and electron avalanche ionization in Kr-Ar gas. The model is validated by earlier experimental data showing strong inhibition of the generation of pulsed, tunable Lyman-{alpha} (Ly-{alpha}) radiation when using sum-difference frequency mixing of 212.6 nm and tunable infrared radiation (820-850 nm). The rigorous computational approach to the problem reveals the possibility and mechanism of strong auto-oscillations in sum-difference resonant Ly-{alpha} generation due to the combined effect of (i) 212.6-nm (2+1)-photon ionization producing initial electrons, followed by (ii) the electron avalanche dominated by 843-nm radiation, and (iii) the final breakdown of the phase matching condition. The model shows that the final efficiency of Ly-{alpha} radiation generation can achieve a value of {approx}5x10{sup -4} which is restricted by the total combined absorption of the fundamental and generated radiation.

  15. Mechanism and computational model for Lyman-α-radiation generation by high-intensity-laser four-wave mixing in Kr-Ar gas

    Science.gov (United States)

    Louchev, Oleg A.; Bakule, Pavel; Saito, Norihito; Wada, Satoshi; Yokoyama, Koji; Ishida, Katsuhiko; Iwasaki, Masahiko

    2011-09-01

    We present a theoretical model combined with a computational study of a laser four-wave mixing process under optical discharge in which the non-steady-state four-wave amplitude equations are integrated with the kinetic equations of initial optical discharge and electron avalanche ionization in Kr-Ar gas. The model is validated by earlier experimental data showing strong inhibition of the generation of pulsed, tunable Lyman-α (Ly-α) radiation when using sum-difference frequency mixing of 212.6 nm and tunable infrared radiation (820-850 nm). The rigorous computational approach to the problem reveals the possibility and mechanism of strong auto-oscillations in sum-difference resonant Ly-α generation due to the combined effect of (i) 212.6-nm (2+1)-photon ionization producing initial electrons, followed by (ii) the electron avalanche dominated by 843-nm radiation, and (iii) the final breakdown of the phase matching condition. The model shows that the final efficiency of Ly-α radiation generation can achieve a value of ˜5×10-4 which is restricted by the total combined absorption of the fundamental and generated radiation.

  16. Dipole oscillator strength distributions with improved high-energy behavior: Dipole sum rules and dispersion coefficients for Ne, Ar, Kr, and Xe revisited

    Science.gov (United States)

    Kumar, Ashok; Thakkar, Ajit J.

    2010-02-01

    The construction of the dipole oscillator strength distribution (DOSD) from theoretical and experimental photoabsorption cross sections combined with constraints provided by the Kuhn-Reiche-Thomas sum rule and molar refractivity data is a well-established technique that has been successfully applied to more than 50 species. Such DOSDs are insufficiently accurate at large photon energies. A novel iterative procedure is developed that rectifies this deficiency by using the high-energy asymptotic behavior of the dipole oscillator strength density as an additional constraint. Pilot applications are made for the neon, argon, krypton, and xenon atoms. The resulting DOSDs improve the agreement of the predicted S2 and S1 sum rules with ab initio calculations while preserving the accuracy of the remainder of the moments. Our DOSDs exploit new and more accurate experimental data. Improved estimates of dipole properties for these four atoms and of dipole-dipole C6 and triple-dipole C9 dispersion coefficients for the interactions among them are reported.

  17. Electronic Spectroscopy of B Atoms and B2 Molecules Isolated in Para-H2, Normal-D2, Ne, Ar, Kr, and Xe Matrices

    Science.gov (United States)

    2007-11-02

    permitted by our apparatus, we calibrate all the spectra to the vacuum wavelengths of the Hg lamp calibration lines. We apply a cubic polynomial fit...solids, we determine the thickness from the intensities of the condensed-phase induced IR absorptions of the pH2 molecules themselves. We use an excimer ...atom emission intensity after just a few hundred excitation laser pulses ; figure 10 depicts the accompanying photobleaching of the B/pH2 absorptions

  18. Intermolecular polarizabilities in H{sub 2}-rare-gas mixtures (H{sub 2}–He, Ne, Ar, Kr, Xe): Insight from collisional isotropic spectral properties

    Energy Technology Data Exchange (ETDEWEB)

    Głaz, Waldemar, E-mail: glaz@kielich.amu.edu.pl; Bancewicz, Tadeusz [Nonlinear Optics Division, Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań (Poland); Godet, Jean-Luc [Laboratoire de photonique d’Angers, Université d’Angers, 2 boulevard Lavoisier, 49045 Angers (France); Gustafsson, Magnus [Department of Chemistry and Molecular Biology, University of Gothenburg, SE 412 96 Gothenburg (Sweden); Maroulis, George; Haskopoulos, Anastasios [Department of Chemistry, University of Patras, GR-26500 Patras (Greece)

    2014-08-21

    The report presents results of theoretical and numerical analysis of the electrical properties related to the isotropic part of the polarizability induced by interactions within compounds built up of a hydrogen H{sub 2} molecule and a set of noble gas atoms, Rg, ranging from the least massive helium up to the heaviest xenon perturber. The Cartesian components of the collisional polarizabilities of the H{sub 2}–Rg systems are found by means of the quantum chemistry methods and their dependence on the intermolecular distance is determined. On the basis of these data, the spherical, symmetry adapted components of the trace polarizability are derived in order to provide data sets that are convenient for evaluating collisional spectral profiles of the isotropic polarized part of light scattered by the H{sub 2}–Rg mixtures. Three independent methods of numerical computing of the spectral intensities are applied at room temperature (295 K). The properties of the roto-translational profiles obtained are discussed in order to determine the role played by contributions corresponding to each of the symmetry adapted parts of the trace polarizability. By spreading the analysis over the collection of the H{sub 2}–Rg systems, evolution of the spectral properties with the growing masses of the supermolecular compounds can be observed.

  19. Darba burtnīca "Es varu" vārdu krājuma paplašināšanai bērniem ar valodas sistēmas nepietiekamu attīstību

    OpenAIRE

    Cīrule, Nora

    2012-01-01

    Diplomdarbā „Darba burtnīca „Es varu” vārdu krājuma paplašināšanai bērniem ar valodas sistēmas nepietiekamu attīstību” autore Nora Cīrule pētīja 5 – 6 gadīgo bērnu ar valodas sistēmas nepietiekamas attīstības III līmeni vārdu krājuma paplašināšanas iespējas ar darba burtnīcu „Es varu” palīdzību. Ievadā tika pamatota tēmas aktualitāte un izklāstīts pētījuma objekts, pētījuma priekšmets, pētījuma mērķis, hipotēze un uzdevumi, pētījumā izmantotās metodes, pētījuma bāze un norises laiks....

  20. Angļu valodas studentu tematiska vārdu krājuma bagātināšana ar datortehnoloģijas rīku palīdzību

    OpenAIRE

    Samčuka, Jeļena

    2012-01-01

    Maģistra darba mērķis bija izpētīt, vai ir iespējams uzlabot konkrētu vārdu apguvi, mācību procesā izmantojot datorprogrammu Quizlet. Pētījuma mērķa sasniegšanai tika aplūkotas teorijas par vārdu krājuma apguvi, tika izpētīta leksikas mācīšanās attīstība, kā arī dažādas pieejas, tai skaitā datorizētā apmācība vārdu krājuma apguvē. Tāpat tika analizēta arī pētnieku attieksme pret datora lietošanu leksikas apguves mācību procesā, kā arī datora izmantošanas priekšrocības un trūkumi. Lai stimulēt...

  1. Analytical formulae for total cross sections for electron scattering by atoms (N, O, F, Ne, P, S, Cl, Ar, As, Se, Br, Kr) between 0.5-10 keV

    Energy Technology Data Exchange (ETDEWEB)

    Williart, A. [Univ. Nacional de Educacion a Distancia, Madrid (Spain). Dept. de Fisica de los Materiales; Garcia, G. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Madrid (Spain)

    2001-10-01

    Analytical formulae for total cross sections for electron scattering by atoms which are close to the noble gases (Ne, Ar and Kr), for electron energies ranging from 0.5 to 10 keV, have been obtained in this study. We have shown, previously, that molecular total cross sections, at these energies, depend on target polarizability and the number of target electrons. A similar behaviour has been supposed for total cross sections of some atoms (N, O, F, P, S, Cl, As, Se and Br). The obtained expression depends on atomic parameters and it is based in some correlation derived from noble gases. The applicability of the formula has been checked by comparison with available data for atomic oxygen. (orig.)

  2. Probing the photochemistry of chemisorbed oxygen on TiO2(110) with Kr and other co-adsorbates.

    Science.gov (United States)

    Petrik, Nikolay G; Kimmel, Greg A

    2014-02-14

    Weakly-bound atoms and molecules (Ar, Kr, Xe, CO, CH4, CO2, CH3OH, N2O, and N2) are used to probe the photochemical interactions of chemisorbed oxygen on rutile TiO2(110). Ultraviolet irradiation of chemisorbed oxygen co-adsorbed with the probe species leads to photon-stimulated desorption (PSD) of some of the probe species (e.g. Kr and CH4), but not others (e.g. CO2 and N2O). Without chemisorbed oxygen, the PSD yields of all the probe species are very low or not observed. Surprisingly, both chemisorbed O2 and oxygen adatoms, Oa, are photo-active for desorption of Kr and other weakly-bound species. To our knowledge, this is the first evidence for photo-activity of Oa on TiO2(110). The Kr PSD yield increases with increasing coverage of Kr and of chemisorbed oxygen. For Kr, the angular distribution of the photodesorbed atoms is approximately cosine. The Kr distribution is quite different from the angular distribution for the O2 PSD, which is sharply peaked along the surface normal. We propose that various forms of chemisorbed oxygen are excited by reactions with electrons and/or holes created in the TiO2 substrate by UV photon irradiation. The photo-excited oxygen collides with, and transfers energy to, neighboring co-adsorbed atoms or molecules. For co-adsorbates with a small enough binding energy to the substrate, desorption may result. The observed phenomenon provides a new tool for studying photochemical processes.

  3. Dziesmas ar kustību un rotaļu elementiem vārdu krājuma apguvei angļu valodas nodarbībās pirmsskolā

    OpenAIRE

    Valdesa, Laura

    2015-01-01

    Tiek plaši uzskatīts, ka mūsdienās rotaļai un spēlei ir nozīmīga loma mācību procesā pirmskolā. Uzdevumi, kuri ir vispiemērotākie angļu valodas apmācībai pirmskolas vecumā ir tie, kas ietver dziesmas ar kustību un rotaļu elementiem, dzejoļus, stāstus, spēles un daudzas citas aktivitātes. Diplomdarba autore uzskata, ka viens no labākiem mācību un vārdu krājuma apguves veidiemdiem ir dziesmas ar kustību un rotaļu elementiem. Diplomdarbs tika izstrādāts, lai izpētīt priekšrocības izmantojot dzie...

  4. Electron-Impact Ionization Cross Sections of H, He, N, O, Ar, Xe, Au, Pb Atoms and Their Ions in the Electron Energy Range from the Threshold up to 200 keV

    CERN Document Server

    Povyshev, V M; Shevelko, V P; Shirkov, G D; Vasina, E G; Vatulin, V V

    2001-01-01

    Single electron-impact ionization cross sections of H, He, N, O, Ar, Xe, Au, Pb atoms and their positive ions (i.e. all ionization stages) are presented in the electron energy range from the threshold up to 200 keV. The data-set for the cross sections has been created on the basis of available experimental data and calculations performed by the computer code ATOM. Consistent data for the ionization cross sections have been fitted by seven parameters using the LSM method. The accuracy of the calculated data presented is within a factor of 2 that in many cases is sufficient to solve the plasma kinetics problems. Contributions from excitation-autoionization and resonant-ionization processes as well as ionization of atoms and ions are not considered here. The results of the numerical calculations are compared with the well-known Lotz formulae for ionization of neutral atoms and positive ions. The material is illustrated by figures and includes tables of ionization cross sections, binding energies and fitting para...

  5. Terrestrial Kr-81-Kr ages of Antarctic meteorites

    Science.gov (United States)

    Freundel, M.; Schultz, L.; Reedy, R. C.

    1986-01-01

    The production rate of Ar-38 in meteorites P(38), has been determined, as a function of the sample's chemical composition, from Kr-81-Kr exposure ages of four eucrite falls. The cosmogenic Kr-78/Kr-83 ratio is used to estimate the shielding dependence of P(38). From the 'true' Ar-38 exposure ages and the apparent Kr-81-Kr exposure ages of nine Antarctic eucrite finds, terrestrial ages are calculated. They range from about 300,000 ages (Pecora Escarpment 82502) to very recent falls (Thiel Mountains 82502). Polymict eucrites from the Allan Hills (A78132, A79017, and A81009) have within the limits of error the same exposure age (15.2 x 10 to the 6th ages) and the same terrestrial age (110,000 ages). This is taken as strong evidence that these meteorites are fragments of the same fall. A similar case is the Elephant Moraine polymict eucrites A79005, A79006, and 82600 with an exposure age of 26 x 10 to the 6th ages and a terrestrial age of 180,000 ages. EETA 79004 may be different from this group because its exposure age and terrestrial age are 21 x 10 to the 6th ages and 250,000 ages, respectively. The distribution of terrestrial ages of Allan Hills meteorites is discussed. Meteorites from this blue ice field have two sources: directly deposited falls and meteorites transported to the Allen Hills inside the moving Antarctic ice sheet. During the surface residence time meteorites decompose due to weathering processes. The weathering 'half-life' is about 160,000 ages. From the different age distributions of Allan Hills and Yamato meteorites, it is concluded that meteorite concentrations of different Antarctic ice fields need different explanations.

  6. Reactive magnetron sputtering of highly (001)-textured WS2-x films: Influence of Ne+, Ar+ and Xe+ ion bombardment on the film growth

    Science.gov (United States)

    Ellmer, K.; Seeger, S.; Sieber, I.; Bohne, W.; Röhrich, J.; Strub, E.; Mientus, R.

    2006-02-01

    Tungsten disulfide WS2 is a layer-type semi-conductor with an energy band gap and an absorption coefficient making it suitable as an absorber for thin film solar cells. In the article [1] WS2-x films were pre-pared by reactive magnetron sputtering from a metallic tungsten target in Ar-H2S atmospheres.The cover figure shows in situ energy-dispersive X-ray diffraction patterns for films deposited at different substrate potentials, i.e. for deposition conditions with ion assistance at different ion energies. These spectra and the corresponding SEM photographs of the film morphology show the strong influence of the ion energy on the film growth. The crystallographic struc-ture of WS2-x is shown between the two SEM pictures.The first author, Klaus Ellmer, is working at the Hahn-Meitner-Institut Berlin, Dept. of Solar Energy Research. His research fields are thin film deposition by reactive magnetron sputtering for solar cells, plasma characterization, in situ energy-dispersive X-ray diffraction and electronic transport in transpar-ent conductive oxides.

  7. Development of refining technology of Xe recovered from reprocessing plant off gas for commercial use

    Energy Technology Data Exchange (ETDEWEB)

    Tomiku, Yasushi [Air Water Inc., Osaka (Japan); Okimoto, Katsunori; Shoji, Hisashi; Hayashi, Sin-ichiro [Japan Nuclear Cycle Development Inst., Tokai Works, Tokai Reprocessing Center, Tokai, Ibaraki (Japan)

    2002-06-01

    The present study is aiming to develop refining system of recovered Xe at Krypton Recovery Facility (KRF) by pressure swing adsorption with purge system for commercial use, such as to lighting and ion engine. Refined Xe with low radioactive Kr was prepared through three series of adsorption column packing synthetic Ca-X zeolite. And the computer simulation by molecular mechanics was practiced to obtain purification mechanism for Xe/Kr mixed gas. The simulation was fitted with the practical adsorption test. So the effects of pressure and cation were studied about adsorption. (author)

  8. Time and Spectrally Resolved Fluorescence of Cl*2 and ArCl* in Cl2 Doped Ar Under State Selective Pulsed Photoexcitation with Synchrotron Radiation

    Science.gov (United States)

    Möller, T.; Jordan, B.; Zimmerer, G.; Haaks, D.; Le Calvé, J.; Castex, M.-C.

    1986-03-01

    Synchrotron Radiation is used to selectively excite chlorine and Cl2 doped argon in the VUV region. Stationary fluorescence and excitation spectra of the 11Σ{/u +}, 21Σ{/u +} and 23Π g Cl{2/*} states and of the ArCl*( B-X) transition are obtained. The excitation threshold of ArCl*( B) in Ar/Cl2 system is found to be 1,285±5 Å and that of ArCl( C) at ˜1,260 Å. The formation of ArCl* and Cl*2(23Π g) is discussed in terms of recent potential curves data. A detailed time resolved study is reported which allows us to determine precisely the radiative lifetime of ArCl*( B) state (5.2 ns) and numerous kinetic parameters of this system, to estimate the C state energy and to discuss the relaxation and mixing process of the ArCl*( B) and ( C) states. A two ladder multilevel kinetic model is described which accounts for the experimental results and shows the difficulty of studying this particular ArCl* system as compared to the closely related XeCl* and KrCl* ones.

  9. Spectroscopic determination of highly nonequilibrium velocity spectra of hydrogen atoms in H{sub 2} + Ne, Ar, Kr hollow-cathode discharges

    Energy Technology Data Exchange (ETDEWEB)

    Lavrov, B.P.; Mel`nikov, A.S. [St. Petersburg State Univ., Peterhof (Russian Federation)

    1995-12-01

    Energy distribution functions of excited (into the state with principal quantum number n = 3) and normal hydrogen atoms in plasma of a hollow-cathode discharge in an H{sub 2} + Ar mixture are determined in the range of 0-120 eV from Doppler profiles of spectral lines of the Balmer series. The distribution functions are found to be substantially nonequilibrium. The analysis of spectral profiles of H{sub {alpha}}lines in plasma of a high-volt-age hollow-cathode discharge in pure hydrogen shows that a part of the high-velocity excited hydrogen atoms is formed through charge exchange of negative H{sup {minus}} ions. Estimates show that the concentration of high-velocity H{sup {minus}} ions does not exceed several percent of the concentration of positive ions and increases with hydrogen pressure. Estimates of relative cross sections for excitation of hydrogen atoms to levels with n = 3, 4, and 5 in collisions of H atorns with H{sub 2} molecules are made. 18 refs., 3 figs., 1 tab.

  10. Geophysical borehole logging of the boreholes KR30, KR31, KR31b, KR32, KR33, KR33b and KR24 Upper Part, at Olkiluoto 2005

    Energy Technology Data Exchange (ETDEWEB)

    Majapuro, J. [Suomen Malmi Oy, Espoo (Finland)

    2005-12-15

    Suomen Malmi Oy conducted geophysical borehole logging of the boreholes KR30, KR31, KR31B, KR32, KR33, KR33B and KR24 upper part at the Olkiluoto site in Eurajoki during December 2004, January, February and September 2005. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and processing of the acoustic data. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality in the appendices. The raw and processed data are delivered digitally in WellCAD and Excel format. (orig.)

  11. Alt koster 10 kr

    DEFF Research Database (Denmark)

    Ejersbo, Lisser Rye

    2014-01-01

    Jeg havde engang en elev, som fortalte, at når han gik i byen for at købe ind, så var det nemt at beregne, om han havde nok penge med i byen. Han sagde bare, at alle varerne kun kostede 10 kr. Det kan lyde som lidt af en tilsnigelse, så klassen og jeg besluttede at undersøge om hans metode virkede....

  12. Hyperpolarized 131Xe NMR spectroscopy

    Science.gov (United States)

    Stupic, Karl F.; Cleveland, Zackary I.; Pavlovskaya, Galina E.; Meersmann, Thomas

    2011-01-01

    Hyperpolarized (hp) 131Xe with up to 2.2% spin polarization (i.e., 5000-fold signal enhancement at 9.4 T) was obtained after separation from the rubidium vapor of the spin-exchange optical pumping (SEOP) process. The SEOP was applied for several minutes in a stopped-flow mode, and the fast, quadrupolar-driven T1 relaxation of this spin I = 3/2 noble gas isotope required a rapid subsequent rubidium removal and swift transfer into the high magnetic field region for NMR detection. Because of the xenon density dependent 131Xe quadrupolar relaxation in the gas phase, the SEOP polarization build-up exhibits an even more pronounced dependence on xenon partial pressure than that observed in 129Xe SEOP. 131Xe is the only stable noble gas isotope with a positive gyromagnetic ratio and shows therefore a different relative phase between hp signal and thermal signal compared to all other noble gases. The gas phase 131Xe NMR spectrum displays a surface and magnetic field dependent quadrupolar splitting that was found to have additional gas pressure and gas composition dependence. The splitting was reduced by the presence of water vapor that presumably influences xenon-surface interactions. The hp 131Xe spectrum shows differential line broadening, suggesting the presence of strong adsorption sites. Beyond hp 131Xe NMR spectroscopy studies, a general equation for the high temperature, thermal spin polarization, P, for spin I⩾1/2 nuclei is presented.

  13. Studies on NaXe Clusters

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The chemical shift of 23Na in excimer NaXe was measured by using nuclear magnetic resonance (NMR) spectra, which is in good agreement with the theoretical value obtained by ab initio calculations. The bond length, dissociation energy, dipole of NaXe and Mulliken charges at Na and Xe in NaXe were calculated, respectively. The spectra of ultraviolet (UV) fluorescence and surface-enhanced Raman scattering of NaXe were also measured.

  14. Geophysical drillhole logging and optical imaging of the drillholes OL-KR43, OL-KR44, OL-KR44B, OL-KR45, OL-KR45B, OL-KR46, OL-KR46B, OL-KR47, OL-KR47B and OL-KR48, at Olkiluoto 2007 and 2008

    Energy Technology Data Exchange (ETDEWEB)

    Tarvainen, A.-M. (Suomen Malmi OY, Espoo (Finland)); Heikkinen, E. (Poeyry Environment Oy (Finland))

    2008-09-15

    Suomen Malmi Oy conducted geophysical drillhole logging and optical imaging of the drillholes OL-KR43, OL-KR44, OL-KR44B, OL-KR45, OL-KR45B, OL-KR46, OL-KR46B, OL-KR47, OL-KR47B and OL-KR48 at the Olkiluoto site in Eurajoki during December 2007, May 2008. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and data processing. The report describes field operation, equipment as well as processing procedures and shows the obtained results and an analysis of their quality in the appendices. The raw and processed data are delivered digitally in WellCAD, PDF and Excel format. (orig.)

  15. The origin of the background radioactive isotope Xe-127 in the sample of Xe enriched in Xe-124

    CERN Document Server

    Gavrilyuk, Yu M; Kazalov, V V; Kuzminov, V V; Panasenko, S I; Ratkevich, S S; Tekueva, D A; Yakimenko, S P

    2015-01-01

    The results of investigation of Xe-127 radioactive isotope production in the xenon sample enriched in Xe-124, Xe-126, Xe-128 are presented. The isotope is supposed to be the source of the background events in the low-background experiment on search for 2K-capture of Xe-124. In this work we consider two channels of Xe-127 production: the neutron knock-out from Xe-128 nucleus by cosmogenic muons and the neutron capture by Xe-126 nucleus. For the first channel the upper limit of the cross section of Xe-127 production was found to be sigma >= 0.007 barn at 95\\% C.L. For the second channel the value obtained for the cross section was found to be equal to sigma =(2.74+-0.4) barn, which coincides well, within the statistical error, with reference value.

  16. The Collectivity in Csr 129Xe+129Xe Collisions

    Science.gov (United States)

    Xie, Fei; Wu, Kejun; Liu, Feng

    The Heavy Ion Research Facility in Lanzhou (HIRFL) - Cooler Storage Ring (CSR), which can gather few hundreds MeV/nucleon for heavy ion beam energy in the external-target experiments, could make a significant contribution in studying the property of dense matter. By using a Relativistic Transport Model(ART1.0), we study the collectivity of identified hadrons in 129Xe+129Xe collisions in CSR energy regions. Our investigation indicates that the anisotropic flow reaches its extremum around 500 MeV/nucleon of beam energy. The system size and EOS dependence on anisotropic flow show that directed flow is very sensitive to the equation of state.

  17. Ars disyecta Ars disyecta

    Directory of Open Access Journals (Sweden)

    Alejandra Castillo

    2012-07-01

    Full Text Available Bajo la nominación Ars Disyecta se busca exponer el vínculo entre artes visuales, feminismo y metamorfosis. Las prácticas artísticas feministas aquí presentadas se proponen perturbar el espacio metafórico heredado de la diferencia sexual (pensemos, por ejemplo, en las palabras engendramiento, matriz, vida, compenetración o invaginamiento. En este sentido, la nominación Ars disyecta pone en escena un conjunto de prácticas e intervenciones que intentan interrumpir la matriz de la diferencia, desestabilizando lo femenino desde aquellas figuras que se resisten a la lógica de la totalidad y de un tiempo propio. Buscando seguir la huella de un arte disyecto es que interrogaré en este ensayo aquellas autorías feministas que en el arte contemporáneo trafican con las huellas del contagio, la mutación y la alteridad.This article aims to present the relation between visual arts, feminism I and metamorphosis. The feminist artistic practices portrayed in this article attempt to question categories inherited from the metaphor of sexual difference such as engendering, matrix and life. From this perspective, Ars disyecta will establish a set of artistic practices and interventions that intend to interrupt the proper idea of «feminine difference». Following this line of argument, I will discuss in this article a few contemporary feminist works of art that could be defined by words such as contagious, mutation and otherness.

  18. Milestone Report - M4FT-15OR03120218 - A Literature Search on the Effects of the Decay of 85Kr to 85Rb on Long-term Storage Options

    Energy Technology Data Exchange (ETDEWEB)

    Bruffey, Stephanie H [ORNL; Jubin, Robert Thomas [ORNL; Spencer, Barry B [ORNL

    2015-10-01

    Reprocessing of UNF that has been out of the reactor for less than about 50 y requires the removal of 85Kr from the process off-gas streams. This is needed despite the relatively small amount of that isotope in the combined Xe and Kr inventory (Table 1). The decay of 85Kr to 85Rb presents challenges to the materials that will potentially be used to remove and store the Kr recovered from the off-gas. To address some of these problems, a thorough literature survey was completed, and the results of that analysis are summarized in this document.

  19. Chronology and shock history of the Bencubbin meteorite: A nitrogen, noble gas, and Ar-Ar investigation of silicates, metal and fluid inclusions

    Science.gov (United States)

    Marty, Bernard; Kelley, Simon; Turner, Grenville

    2010-11-01

    We have investigated the distribution and isotopic composition of nitrogen and noble gases, and the Ar-Ar chronology of the Bencubbin meteorite. Gases were extracted from different lithologies by both stepwise heating and vacuum crushing. Significant amounts of gases were found to be trapped within vesicles present in silicate clasts. Results indicate a global redistribution of volatile elements during a shock event caused by an impactor that collided with a planetary regolith. A transient atmosphere was created that interacted with partially or totally melted silicates and metal clasts. This atmosphere contained 15N-rich nitrogen with a pressure ⩾3 × 10 5 hPa, noble gases, and probably, although not analyzed here, other volatile species. Nitrogen and noble gases were re-distributed among bubbles, metal, and partly or totally melted silicates, according to their partition coefficients among these different phases. The occurrence of N 2 trapped in vesicles and dissolved in silicates indicates that the oxygen fugacity ( fO2) was greater than the iron-wüstite buffer during the shock event. Ar-Ar dating of Bencubbin glass gives an age of 4.20 ± 0.05 Ga, which probably dates this impact event. The cosmic-ray exposure age is estimated at ˜40 Ma with two different methods. Noble gases present isotopic signatures similar to those of "phase Q" (the major host of noble gases trapped in chondrites) but elemental patterns enriched in light noble gases (He, Ne and Ar) relative to Kr and Xe, normalized to the phase Q composition. Nitrogen isotopic data together with 40Ar/ 36Ar ratios indicate mixing between a 15N-rich component (δ 15N = +1000‰), terrestrial N, and an isotopically normal, chondritic N. Bencubbin and related 15N-rich meteorites of the CR clan do not show stable isotope (H and C) anomalies, precluding contribution of a nucleosynthetic component as the source of 15N enrichments. This leaves two possibilities, trapping of an ancient, highly fractionated

  20. A New Method of Measuring 81Kr and 85Kr Abundances in Environmental Samples

    CERN Document Server

    Du, X; Bailey, K; Lehmann, B E; Lorenzo, R; Lu, Z T; Müller, P; O'Connor, T P; Sturchio, N C; Young, L

    2003-01-01

    We demonstrate a new method for determining the 81Kr/Kr ratio in environmental samples based upon two measurements: the 85Kr/81Kr ratio measured by Atom Trap Trace Analysis (ATTA) and the 85Kr/Kr ratio measured by Low-Level Counting (LLC). This method can be used to determine the mean residence time of groundwater in the range of 10^5 - 10^6 a. It requires a sample of 100 micro-l STP of Kr extracted from approximately two tons of water. With modern atmospheric Kr samples, we demonstrate that the ratios measured by ATTA and LLC are directly proportional to each other within the measurement error of +/- 10%; we calibrate the 81Kr/Kr ratio of modern air measured using this method; and we show that the 81Kr/Kr ratios of samples extracted from air before and after the development of the nuclear industry are identical within the measurement error.

  1. (129) Xe and (131) Xe nuclear magnetic dipole moments from gas phase NMR spectra.

    Science.gov (United States)

    Makulski, Włodzimierz

    2015-04-01

    (3) He, (129) Xe and (131) Xe NMR measurements of resonance frequencies in the magnetic field B0=11.7586 T in different gas phase mixtures have been reported. Precise radiofrequency values were extrapolated to the zero gas pressure limit. These results combined with new quantum chemical values of helium and xenon nuclear magnetic shielding constants were used to determine new accurate nuclear magnetic moments of (129) Xe and (131) Xe in terms of that of the (3) He nucleus. They are as follows: μ((129) Xe) = -0.7779607(158)μN and μ((131) Xe) = +0.6918451(70)μN . By this means, the new 'helium method' for estimations of nuclear dipole moments was successfully tested. Gas phase NMR spectra demonstrate the weak intermolecular interactions observed on the (3) He and (129) Xe and (131) Xe shielding in the gaseous mixtures with Xe, CO2 and SF6 .

  2. Adsorption of Xe in zeolite MCM-22

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Adsorption of xenon in zeolite MCM-22, a zeo lite containing two separate pore systems, has been investigated in detail by variable temperature (VT) 129Xe NMR spectroscopy. NMR results suggest that Xe atoms are preferentially adsorbed in the supercages of the zeolite at low Xe pressure (less than a few atmosphere), while Xe atoms can penetrate into the two-dimensional sinusoidal channels at high Xe pressure. Exchange of xenon at the different adsorption sites in the same supercage, i.e. xenon atoms in the two pockets and those in the central part of the supercage, was confirmed at 145 K by two-dimensional (2D) 129Xe NMR exchange spectroscopy. The time scale for the exchange is about several milliseconds.

  3. Kr-KCl exciplex lamp

    Science.gov (United States)

    Klenovskii, M. S.; Riives, R. B.; Kel'Man, V. A.; Zhmenyak, Yu. V.; Shpenik, Yu. O.

    2009-07-01

    A new source of UV radiation (excilamp) based on Kr-KCl vapor-gas mixture excited by a longitudinal high-voltage pulsed-periodic discharge is created. The emission spectrum and time characteristic of the discharge radiation are studied. The B → X transition in the KrCl* excimer molecule (λ = 222 nm) is found to dominate in the radiation spectrum of the source. The dependence of the pulse output power of the lamp on various factors is investigated, and the mechanism of B state formation in the excimer molecule is discussed.

  4. Radiometric 81Kr dating identifies 120,000-year-old ice at Taylor Glacier, Antarctica.

    Science.gov (United States)

    Buizert, Christo; Baggenstos, Daniel; Jiang, Wei; Purtschert, Roland; Petrenko, Vasilii V; Lu, Zheng-Tian; Müller, Peter; Kuhl, Tanner; Lee, James; Severinghaus, Jeffrey P; Brook, Edward J

    2014-05-13

    We present successful (81)Kr-Kr radiometric dating of ancient polar ice. Krypton was extracted from the air bubbles in four ∼350-kg polar ice samples from Taylor Glacier in the McMurdo Dry Valleys, Antarctica, and dated using Atom Trap Trace Analysis (ATTA). The (81)Kr radiometric ages agree with independent age estimates obtained from stratigraphic dating techniques with a mean absolute age offset of 6 ± 2.5 ka. Our experimental methods and sampling strategy are validated by (i) (85)Kr and (39)Ar analyses that show the samples to be free of modern air contamination and (ii) air content measurements that show the ice did not experience gas loss. We estimate the error in the (81)Kr ages due to past geomagnetic variability to be below 3 ka. We show that ice from the previous interglacial period (Marine Isotope Stage 5e, 130-115 ka before present) can be found in abundance near the surface of Taylor Glacier. Our study paves the way for reliable radiometric dating of ancient ice in blue ice areas and margin sites where large samples are available, greatly enhancing their scientific value as archives of old ice and meteorites. At present, ATTA (81)Kr analysis requires a 40-80-kg ice sample; as sample requirements continue to decrease, (81)Kr dating of ice cores is a future possibility.

  5. Liquid Xe scintillation calorimetry and Xe optical properties

    CERN Document Server

    Baldini, A; Cei, F; Doke, T; Grassi, M; Haruyama, T; Mihara, S; Mori, T; Nicolò, D; Nishiguchi, H; Ootani, W; Ozone, K; Papa, A; Pazzi, R; Sawada, R; Sergiampietri, F; Signorelli, G; Suzuki, S; Terasawa, K

    2004-01-01

    The optical properties of LXe in the vacuum ultra violet (VUV), determining the performance of a scintillation calorimeter, are discussed in detail. The available data, measured in a wider spectral region from visible to UV light, and in a large range of Xe densities, from gas to liquid, are examined. It is shown that this information can be used for deriving the LXe optical properties in the VUV. A comparison is made with the few direct measurements in LXe for VUV light resulting from the LXe excitation by ionizing particles. A useful relation is obtained which connects the Rayleigh scattering length to the refractive index in LXe.

  6. 124Xe(n,γ125Xe and 124Xe(n,2n123Xe measurements for National Ignition Facility

    Directory of Open Access Journals (Sweden)

    Bhike Megha

    2015-01-01

    Full Text Available The cross section for the 124Xe(n,γ125Xe reaction has been measured for the first time for neutron energies above 100 keV. In addition, the 124Xe(n,2n123Xe reaction has been studied between threshold and 14.8 MeV. The results of these measurements provide sensitive diagnostic tools for investigating properties of the inertial confinement fusion plasma in Deuterium-Tritium (DT capsules at the National Ignition Facility (NIF located at Lawrence Livermore National Laboratory.

  7. Range-separated density functional theory: A 4-component relativistic study of the rare gas dimers He{sub 2}, Ne{sub 2}, Ar{sub 2}, Kr{sub 2}, Xe{sub 2}, Rn{sub 2} and Uuo{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Kullie, Ossama [Institute de Chimie de Strasbourg, CNRS et Universite de Strasbourg, Laboratoire de Chimie Quantique, 4 rue Blaise Pascal, 67070 Strasbourg (France); Saue, Trond, E-mail: trond.saue@isamc.ups-tlse.fr [Laboratoire de Chimie et Physique Quantique (UMR 5626), CNRS/Universite de Toulouse 3 (Paul Sabatier), 118 route de Narbonne, 31062 Toulouse (France)

    2012-02-20

    Highlights: Black-Right-Pointing-Pointer First implementation of 4-component relativistic long-range MP2/short-range DFT. Black-Right-Pointing-Pointer First complete study of spectroscopic constants of the rare gas dimers He{sub 2}-Uuo{sub 2}. Black-Right-Pointing-Pointer MP2-srLDA has a performance similar to pure MP2, but the overbinding of MP2 can be tuned by the range-separation parameter. - Abstract: We report the implementation of long-range second-order Moller-Plesset perturbation theory coupled with short-range density functional theory (MP2-srDFT) based on the 4-component relativistic Dirac-Coulomb Hamiltonian. The range separation of the two-electron interaction is based on the error function, such that the long-range interaction, to be handled by wave function theory, corresponds to the potential of finite electrons with a Gaussian charge distribution. We argue that the interelectronic distance associated with the range-separation parameter should accordingly be determined from a Gaussian rather than a hard-sphere model. As a first application of our relativistic MP2-srDFT implementation we calculate spectroscopic constants of the complete series of homoatomic rare gas dimers, from helium to the superheavy element 118 and with bonding dominated by dispersion forces. We find that the MP2-srDFT method is less sensitive to the basis set quality than pure MP2, but for the heavier rare gas dimers the computational cost is approximately the same as for pure MP2 if one seeks convergence with respect to both basis set and number of correlated electrons. The inclusion of a short-range DFT contribution allows to dampen the tendency of pure MP2 to overbind the heavier dimers, but it is difficult to find an optimal range-separation parameter for the whole series of diatomics. Interestingly, MP2-srLDA shows better performance than MP2-srPBE for the selected molecules.

  8. Large aperture discharge-pumped KrF laser for picosecond amplification

    CERN Document Server

    Yuan Xiao; LiuJingRu; Goldhar, J

    2002-01-01

    A large aperture discharge-pumped KrF laser module with simple spark gaps was developed. The laser beam cross section of 4 cm x 3 cm and the maximum laser output energy of 1.3J in 20ns were obtained at the charging voltage of 30 kV and gas mixtures of [F sub 2] : [Kr] : [Ne] = 0.1 : 2 : 97.9. The gain and absorption coefficients at different gas mixtures were measured with a frequency doubled dye laser pumped by a XeCl laser. Using this laser module as a ps amplifier, the output energy of 140 mJ in 10 ps was obtained

  9. Ion mobilities in Xe/Ne and other rare-gas mixtures.

    Science.gov (United States)

    Piscitelli, D; Phelps, A V; de Urquijo, J; Basurto, E; Pitchford, L C

    2003-10-01

    The ion mobility or drift velocity data important for modeling glow discharges in rare gas mixtures are not generally available, nor are the ion-neutral scattering cross sections needed to calculate these data. In this paper we propose a set of cross sections for Xe+ and Ne+ collisions with Xe and Ne atoms. Ion mobilities at 300 K calculated using this cross section set in a Monte Carlo simulation are reported for reduced field strengths, E/N, up to 1500 x 10(-21) V m(2), in pure gases and in Xe/Ne mixtures containing 5% and 20% Xe/Ne, which are mixtures of interest for plasma display panels (PDPs). The calculated Xe+ mobilities depend strongly on the mixture composition, but the Ne+ mobility varies only slightly with increasing Xe in the mixture over the range studied here. The mobilities in pure gases compare well with available experimental values, and mobilities in gas mixtures at low E/N compare well with our recent measurements which will be published separately. Results from these calculations of ion mobilities are used to evaluate the predictions of Blanc's law and of the mixture rule proposed by Mason and Hahn [Phys. Rev. A 5, 438 (1972)] for determining the ion mobilities in mixtures from a knowledge of the mobilities in each of the pure gases. The mixture rule of Mason and Hahn is accurate to better than 10% at high field strengths over a wide range of conditions of interest for modeling PDPs. We conclude that a good estimate of ion mobilities at high E/N in Xe/Ne and other binary rare gas mixtures can be obtained using this mixture rule combined with known values of mobilities in parent gases and with the Langevin form for mobility of rare gas ions ion in other gases. This conclusion is supported by results in Ar/Ne mixtures which are also presented here.

  10. Interruption of electronically excited Xe dimer formation by the photoassociation of Xe(6s[3/2]2)-Xe(5p(6) (1)S0) thermal collision pairs.

    Science.gov (United States)

    Galvin, T C; Wagner, C J; Eden, J G

    2016-06-28

    The diatomic collisional intermediate responsible for the formation of an electronically excited molecule by teratomic recombination has been observed in both the spectral and temporal domains by laser spectroscopy. We report experiments demonstrating thermal Xe(6s[3/2]2)-Xe(5p(6) (1)S0) atomic collision pairs to be the immediate precursor to the formation of Xe2 (∗)(a(3)Σu (+),A(1)Σu (+)) by the three body process: Xe(∗)(6s) + 2XeXe2 (∗) + Xe, where the asterisk denotes an excited electronic state. Photoassociating Xe(6s)-Xe atomic pairs by free ⟵ free transitions of the collision complex interrupts the production of the electronically excited Xe dimer, thereby suppressing Xe2 spontaneous emission in the vacuum ultraviolet (VUV, λ ∼ 172 nm, A(1)Σu (+)→X(1)Σg (+)). Intercepting Xe(6s)-Xe pairs before the complex is stabilized by the arrival of the third atom in the teratomic collision process selectively depletes the pair population in a specific Franck-Condon region determined by the probe laser wavelength (λ). Measurements of the variation of VUV emission suppression with λ provide a spectral signature of the [Xe(6s[3/2]2) - Xe((1)S0)](∗) complex and map the probe laser wavelength onto the thermal energy (ϵ″) of the incoming collision pairs.

  11. Characterization of a cryogenic distillation column with a Kr-83m tracer method

    Energy Technology Data Exchange (ETDEWEB)

    Rosendahl, Stephan; Fieguth, Alexander; Huhmann, Chrisian; Murra, Michael; Weinheimer, Christian [Institut fuer Kernphysik, Wilhelm-Klemm Strasse 9, 48149 Muenster (Germany); Cristescu, Ion [Karlsruher Institut fuer Technologie, Tritium Laboratory, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2016-07-01

    The XENON1T experiment aims for the direct detection of dark matter with unreached precision of 2 x 10{sup -47} cm{sup 2} for the spin-independent WIMP-nucleon cross section. The cryogenic distillation is an important tool to reduce the intrinsic contamination with radioactive {sup 85}Kr which undergoes a beta-decay with an endpoint energy of 687 keV, being one major source of background. Hence, a novel cryogenic distillation column has been designed and constructed in order to reduce the krypton concentration to {sup nat}Kr/Xe<0.2 ppt. For the investigation of the performance and the dynamics of the distillation process on the sub-ppt level, a new {sup 83m}Kr tracer method has been applied. For the {sup 83m}Kr detection custom made PMT based detectors are used. In this talk the method as well as the results of the studies of the krypton separation are presented.

  12. Parameter analysis for a nuclear magnetic resonance gyroscope based on 133Cs–129Xe/131Xe

    Science.gov (United States)

    Zhang, Da-Wei; Xu, Zheng-Yi; Zhou, Min; Xu, Xin-Ye

    2017-02-01

    We theoretically investigate several parameters for the nuclear magnetic resonance gyroscope based on 133Cs–129Xe/131Xe. For a cell containing a mixture of 133Cs at saturated pressure, we investigate the optimal quenching gas (N2) pressure and the corresponding pump laser intensity to achieve 30% 133Cs polarization at the center of the cell when the static magnetic field B 0 is 5 {{μ }}{{T}} with different 129Xe/131Xe pressure. The effective field produced by spin-exchange polarized 129Xe or 131Xe sensed by 133Cs can also be discussed in different 129Xe/131Xe pressure conditions. Furthermore, the relationship between the detected signal and the probe laser frequency is researched. We obtain the optimum probe laser detuning from the D2 (6{}2{{S}}1/2\\to 6{}2{{P}}3/2) resonance with different 129Xe/131Xe pressure owing to the pressure broadening. Project supported by the National High Technology Research and Development Program of China (Grant No. 2014AA123401), the National Key Basic Research and Development Program of China (Grant Nos. 2016YFA0302103 and 2012CB821302), the National Natural Science Foundation of China (Grant 11134003), and Shanghai Excellent Academic Leaders Program of China (Grant No. 12XD1402400).

  13. Performance of XeF/KrF Lasers Pumped by Fast Discharge

    Science.gov (United States)

    2007-11-02

    space astronomy, x-ray astronomy; the effects of nuclear explosions , magnetic storms, and solar activity on the earth’s atmosphere, ionosphere...Westberg R. L. Wilkins External SAMSO Lt. Col. Staubs (DYN) Lt. Col. J. R. Doughty (DYV) AFWL Kirtland AFB, NM 87117 Col. R

  14. Interruption of electronically excited Xe dimer formation by the photoassociation of Xe(6s[3/2]2)-Xe(5p6 1S0) thermal collision pairs

    Science.gov (United States)

    Galvin, T. C.; Wagner, C. J.; Eden, J. G.

    2016-06-01

    The diatomic collisional intermediate responsible for the formation of an electronically excited molecule by teratomic recombination has been observed in both the spectral and temporal domains by laser spectroscopy. We report experiments demonstrating thermal Xe(6s[3/2]2)-Xe(5p6 1S0) atomic collision pairs to be the immediate precursor to the formation of Xe 2∗ ( a 3 Σu + , A 1 Σu +) by the three body process: Xe∗(6s) + 2XeXe 2∗ + Xe, where the asterisk denotes an excited electronic state. Photoassociating Xe(6s)-Xe atomic pairs by free ⟵ free transitions of the collision complex interrupts the production of the electronically excited Xe dimer, thereby suppressing Xe2 spontaneous emission in the vacuum ultraviolet (VUV, λ ˜ 172 nm, A 1 Σu + → X 1 Σg +). Intercepting Xe(6s)-Xe pairs before the complex is stabilized by the arrival of the third atom in the teratomic collision process selectively depletes the pair population in a specific Franck-Condon region determined by the probe laser wavelength (λ). Measurements of the variation of VUV emission suppression with λ provide a spectral signature of the [Xe(6s[3/2]2) - Xe(1S0)]∗ complex and map the probe laser wavelength onto the thermal energy (ɛ″) of the incoming collision pairs.

  15. Geophysical borehole logging of the boreholes KR23 extension, KR29 and KR29b at Olkiluoto 2004

    Energy Technology Data Exchange (ETDEWEB)

    Lahti, M. [Suomen Malmi Oy, Espoo (Finland); Heikkinen, E. [JP-Fintact Oy, Vantaa (Finland)

    2005-04-15

    Suomen Malmi Oy conducted geophysical borehole logging of the boreholes KR23 extension, KR25b, KR29 and KR29b at the Olkiluoto site in Eurajoki during October 2004. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and processing of the acoustic data. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality in the appendices. The raw and processed data are delivered digitally in WellCAD and Excel format. (orig.)

  16. Ars Electronica

    DEFF Research Database (Denmark)

    Kristensen, Thomas Bjørnsten

    2009-01-01

    Anmeldelse af Ars Electronica festivalen 3. - 8. september, 2009 i Linz, Østrig, der fejrede 30 års jubilæum under temaet "Human Nature". Festivalen fokuserer på interaktion mellem menneske, teknologi, kunst og samfund med særlig vægt på udviklingen af computeren og det digitale. Udgivelsesdato: 15.12...

  17. Longitudinal discharge pumped low-pressure XeCl laser

    Science.gov (United States)

    Fedorov, A. I.

    2013-10-01

    We have studied output parameters of a XeCl and a N2 laser pumped by a longitudinal discharge with automatic spark UV preionisation. The output parameters of a low-pressure (30 Torr) XeCl laser operating with Ar, Ne and He as buffer gases or with no buffer gas have been optimised for the first time. The laser generated 5-ns FWHM pulses with an average power of 0.5 mW and output energy of 0.15 mJ. Under longitudinal discharge pumping, an output energy per unit volume of 1.8 J L-1 atm-1 was reached using helium as a buffer gas. With argon-containing and buffer-free mixtures, it was 1.5 J L-1 atm-1. The N2 laser generated 2.5-ns FWHM pulses with an average power of 0.35 mW and output energy of 0.05 mJ.

  18. Inner-shell photoionization and core-hole decay of Xe and XeF$_2$

    CERN Document Server

    Southworth, Stephen H; Picón, Antonio; Lehmann, C Stefan; Cheng, Lan; Stanton, John F

    2015-01-01

    Photoionization cross sections and partial ion yields of Xe and XeF$_2$ from Xe 3d$_{5/2}$, Xe 3d$_{3/2}$, and F 1s subshells in the 660--740 eV range are compared to explore effects of the F ligands. The Xe 3d - $\\epsilon$f continuum shape resonances dominate the photoionization cross sections of both the atom and molecule, but prominent resonances appear in the XeF$_2$ cross section due to nominal excitation of Xe 3d and F 1s electrons to the lowest unoccupied molecular orbital (LUMO), a delocalized anti-bonding MO. The subshell ionization thresholds, the LUMO resonance energies and their oscillator strengths are calculated by relativistic coupled-cluster methods. Several charge states and fragment ions are produced from the atom and molecule due to alternative decay pathways from the inner-shell holes. Total and partial ion yields vary in response to the shape resonances and LUMO resonances. Previous calculations and measurements of atomic Xe 3d core-hole decay channels and our calculated results for XeF$_...

  19. Geophysical logging and imaging of drillholes OL-KR45, OL-KR49, OL-KR50 and OL-KR50B at Olkiluoto in 2009

    Energy Technology Data Exchange (ETDEWEB)

    Tarvainen, A.-M. (Suomen Malmi Oy, Espoo (Finland))

    2010-04-15

    Suomen Malmi Oy conducted geophysical drillhole logging, acoustic imaging and optical imaging of the drillholes OL-KR45 (re-measurements), OL-KR49, OL-KR50 and OL-KR50B at the Olkiluoto site in Eurajoki during January-November 2009. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and data processing. The report describes field operation, equipment as well as processing procedures and shows the obtained results and an analysis of their quality in the appendices. The raw and processed data are delivered digitally in WellCAD, PDF and Excel format. The missing density logging of drillhole OL-KR45 was carried out successfully. Dynamic rock mechanical parameters and natural gamma data were re-processed and this report includes updated WellCAD and Excel files. Acoustic imaging was also carried out in OL-KR45 after 700 meters depth. Acoustic imaging was used instead of optical imaging after 350 meters in OL-KR49 and 700 meters in OL-KR50. (orig.)

  20. Radiometric 81Kr dating identifies 120,000 year old ice at Taylor Glacier, Antarctica

    CERN Document Server

    Buizert, Christo; Jiang, Wei; Purtschert, Roland; Petrenko, Vasilii V; Lu, Zheng-Tian; Mueller, Peter; Kuhl, Tanner; Lee, James; Severinghaus, Jeffrey P; Brook, Edward J

    2014-01-01

    We present the first successful 81Kr-Kr radiometric dating of ancient polar ice. Krypton was extracted from the air bubbles in four ~350 kg polar ice samples from Taylor Glacier in the McMurdo Dry Valleys, Antarctica, and dated using Atom Trap Trace Analysis (ATTA). The 81Kr radiometric ages agree with independent age estimates obtained from stratigraphic dating techniques with a mean absolute age offset of 6 +/- 2.5 ka. Our experimental methods and sampling strategy are validated by 1) 85Kr and 39Ar analyses that show the samples to be free of modern air contamination, and 2) air content measurements that show the ice did not experience gas loss. We estimate the error in the 81Kr ages due to past geomagnetic variability to be below 3 ka. We show that ice from the previous interglacial period (MIS 5e, 130-115 ka before present) can be found in abundance near the surface of Taylor Glacier. Our study paves the way for reliable radiometric dating of ancient ice in blue ice areas and margin sites where large samp...

  1. The production rate of cosmogenic 21-Ne in chondrites deduced from 81-Kr measurements

    Science.gov (United States)

    Schultz, L.; Freundel, M.

    1986-01-01

    Cosmogenic Ne-21 is used widely to calculate exposure ages of stone meteorites. In order to do so, the production rate P(21) must be known. This rate, however, is dependent on the chemical composition of the meteorite as well as the mass of, and position within, the meteoroid during its exposure to the cosmic radiation. Even for a mean shielding the production rates determined from measurments of different radionuclides vary by a factor of two. A method that can be used to determine exposure ages of meteorites that avoids shielding and chemical composition corrections is the -81-Kr-Kr-method. However, for chondrites, in many cases, the direct determination of production rates for the Kr isotopes is prevented by the trapped gases and the neutron effects on bromine. Therefore, this method was applied to four eucrite falls and then their 81-Kr-83-Kr-ages were compared to their cosmogenic Ne-21 and Ar-38 concentrations. The eucrites Bouvante-le-Haut, Juvinas, Sioux County, and Stannern were chosen for these measurements because of their similar chemical composition regarding the major elements.

  2. Geophysical logging and imaging of characterisation drillholes ONK-KR13, ONK-KR14 and ONK-KR15

    Energy Technology Data Exchange (ETDEWEB)

    Tarvainen, A.-M. (Suomen Malmi Oy, Espoo (Finland))

    2011-08-15

    Suomen Malmi Oy conducted geophysical drillhole logging as well as optical and acoustic imaging of drillholes ONK-KR13, ONK-KR14 and ONK-KR15 at ONKALO in June-July 2010 and in March 2011. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and data processing. The report describes field operation, equipment as well as processing procedures and shows the obtained results and an analysis of their quality in the appendices. The raw and processed data are delivered digitally in WellCAD, PDF and Excel format. (orig.)

  3. Drillhole gamma-ray spectrum logging in drillholes OL-KR11, OL-KR44, OL-KR44B, OL-KR45B, OL-KR46, OL-KR47, OL-KR47B, OL-KR48 and ground survey at Olkiluoto in Eurajoki, 2007 and 2008

    Energy Technology Data Exchange (ETDEWEB)

    Julkunen, A.; Kallio, L.; Kuusisto, M. (Astrock Oy, Sodankylae (Finland))

    2009-09-15

    The aim of the detailed drillhole surveys is to increase the knowledge of the bedrock on the study area and to supplement the investigations made earlier. As a part of the detailed investigations Astrock Oy carried out drillhole spectrometer logging in drillholes OL-KR11, OL-KR44, OL-KR44B, OL-KR45B, OL-KR46, OL-KR47, OL-KR47B, OL-KR48 and ground survey at Olkiluoto site in Eurajoki during 2007 and 2008. This report describes the logging, data processing and the results. For the first time the results contains moving standard deviation calculations of Th/K ratio, because the variability of Th/K ratio is a reasonably good indicator of alteration zones. This report includes also moving standard deviation calculations of Th/K ratio from earlier measured and reported drillholes OL-KR40-43 and OL-KR40B-43B. (orig.)

  4. The structure, properties, and nature of HArF-benzene complex: redshift and blueshift of Ar-H stretch frequency and rare gas atomic number dependence of hydrogen bonds.

    Science.gov (United States)

    Liu, Xiaofeng; Li, Qingzhong; Li, Ran; Li, Wenzuo; Cheng, Jianbo

    2011-12-15

    Ab initio calculations have been performed for the complexes of benzene with HArF, HKrF, and HXeF. The computed results indicate that the complexes of benzene-HArF exist in different conformations and among them those with π-hydrogen bonds are the more stable than those with C-H···F hydrogen bonds. Interestingly, the Ar-H stretching frequency is redshifted in the more stable isomer and blueshifted in the less stable form. The Ng (Ng=Ar, Kr, and Xe) atomic number dependence of the Ng-H···π and C-H···F hydrogen bonds has been explored. The result indicates that the strength of Ng-H···π and C-H···F hydrogen bonds is weakened with the increase of Ng atomic number. Natural bond orbital analysis has been performed to understand the interaction nature, frequency shift of H-Ng stretch, and dependence of Ng-H···π and C-H···F hydrogen bonds on the Ng atomic number.

  5. Synthesis and stability of xenon oxides Xe2O5 and Xe3O2 under pressure

    Science.gov (United States)

    Dewaele, Agnès; Worth, Nicholas; Pickard, Chris J.; Needs, Richard J.; Pascarelli, Sakura; Mathon, Olivier; Mezouar, Mohamed; Irifune, Tetsuo

    2016-08-01

    The noble gases are the most inert group of the periodic table, but their reactivity increases with pressure. Diamond-anvil-cell experiments and ab initio modelling have been used to investigate a possible direct reaction between xenon and oxygen at high pressures. We have now synthesized two oxides below 100 GPa (Xe2O5 under oxygen-rich conditions, and Xe3O2 under oxygen-poor conditions), which shows that xenon is more reactive under pressure than predicted previously. Xe2O5 was observed using X-ray diffraction methods, its structure identified through ab initio random structure searching and confirmed using X-ray absorption and Raman spectroscopies. The experiments confirm the recent prediction of Xe3O2 as a stable xenon oxide under high pressure. Xenon atoms adopt mixed oxidation states of 0 and +4 in Xe3O2 and +4 and +6 in Xe2O5. Xe3O2 and Xe2O5 form extended networks that incorporate oxygen-sharing XeO4 squares, and Xe2O5 additionally incorporates oxygen-sharing XeO5 pyramids. Other xenon oxides (XeO2, XeO3) are expected to form at higher pressures.

  6. Xe-bearing hydrocarbon ions: Observation of Xe.acetylene+rad and Xe.benzene+rad radical cations and calculations of their ground state structures

    Science.gov (United States)

    Cui, Zhong-hua; Attah, Isaac K.; Platt, Sean P.; Aziz, Saadullah G.; Kertesz, Miklos; El-Shall, M. S.

    2016-04-01

    This work reports evidence for novel types of Xe-bearing hydrocarbon radical cations. The Xe.acetylene+rad radical cation adduct is observed at nearly room temperature using the mass-selected drift cell technique. The irreversible addition of the Xe atom and the lack of back dissociation to HCCH+rad + Xe is consistent with the calculated binding energy of 0.85 eV to be contrasted with the metastable nature of the neutral Xe.acetylene adduct. The observed Xe.benzene+rad radical cation appears to be a weakly bound complex stabilized mainly by ion-induced dipole interaction consistent with a calculated binding energy in the range of 0.14-0.17 eV.

  7. Observation of the intermediate states in the (Xe-Cl 2)*→ XeCl* (B,C) + Cl reaction

    Science.gov (United States)

    Boivineau, M.; Le Calvé, J.; Castex, M. C.; Jouvet, C.

    1986-10-01

    The Xe-Cl 2 van der Waals complex formed in a supersonic expansion is excited in a two-photon process. The XeCl(B,C) reaction spectra (excitation of the complex and detection of the XeCl (B→X) and (C→A) fluorescence) are obtained in the region 290-310 nm. In addition to a diffuse band also obtained in the C action spectrum, the B action spectrum presents a vibronic structure similar to the Xe-Cl (B←X) absorption band. Xe-Cl 2 ( 1Π u) resonantly enhanced two-photon process with two chromophores is proposed to account for the results.

  8. Geophysical borehole logging and optical imaging of the boreholes KR34, KR35 and KR36, at Olkiluoto 2005

    Energy Technology Data Exchange (ETDEWEB)

    Majapuro, J. [Suomen Malmi Oy, Espoo (Finland)

    2005-09-15

    Suomen Malmi Oy conducted geophysical borehole logging and optical imaging surveys of the boreholes KR34, KR35 and KR36 at the Olkiluoto site in Eurajoki during May - June 2005. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The methods applied are magnetic susceptibility, natural gamma radiation, gamma-gamma density, single point resistance, Wenner-resistivity, borehole radar, full waveform sonic and optical imaging. The assignment included the field work of all surveys, interpretation and processing of the acoustic and borehole radar data. The report describes the field operation, equipment as well as processing procedures and shows the obtained results and their quality in the appendices. The raw and processed data are delivered digitally in WellCAD and Excel format. (orig.)

  9. Ar-Ar_Redux: rigorous error propagation of 40Ar/39Ar data, including covariances

    Science.gov (United States)

    Vermeesch, P.

    2015-12-01

    Rigorous data reduction and error propagation algorithms are needed to realise Earthtime's objective to improve the interlaboratory accuracy of 40Ar/39Ar dating to better than 1% and thereby facilitate the comparison and combination of the K-Ar and U-Pb chronometers. Ar-Ar_Redux is a new data reduction protocol and software program for 40Ar/39Ar geochronology which takes into account two previously underappreciated aspects of the method: 1. 40Ar/39Ar measurements are compositional dataIn its simplest form, the 40Ar/39Ar age equation can be written as: t = log(1+J [40Ar/39Ar-298.5636Ar/39Ar])/λ = log(1 + JR)/λ Where λ is the 40K decay constant and J is the irradiation parameter. The age t does not depend on the absolute abundances of the three argon isotopes but only on their relative ratios. Thus, the 36Ar, 39Ar and 40Ar abundances can be normalised to unity and plotted on a ternary diagram or 'simplex'. Argon isotopic data are therefore subject to the peculiar mathematics of 'compositional data', sensu Aitchison (1986, The Statistical Analysis of Compositional Data, Chapman & Hall). 2. Correlated errors are pervasive throughout the 40Ar/39Ar methodCurrent data reduction protocols for 40Ar/39Ar geochronology propagate the age uncertainty as follows: σ2(t) = [J2 σ2(R) + R2 σ2(J)] / [λ2 (1 + R J)], which implies zero covariance between R and J. In reality, however, significant error correlations are found in every step of the 40Ar/39Ar data acquisition and processing, in both single and multi collector instruments, during blank, interference and decay corrections, age calculation etc. Ar-Ar_Redux revisits every aspect of the 40Ar/39Ar method by casting the raw mass spectrometer data into a contingency table of logratios, which automatically keeps track of all covariances in a compositional context. Application of the method to real data reveals strong correlations (r2 of up to 0.9) between age measurements within a single irradiation batch. Propertly taking

  10. Geophysical drillhole logging and imaging of drillholes OL-KR51, OL-KR52, OL-KR52B, OL-KR53 and OL-KR53B at Olkiluoto in 2009 and 2010

    Energy Technology Data Exchange (ETDEWEB)

    Tarvainen, A.-M. (Suomen Malmi Oy, Espoo (Finland))

    2010-10-15

    Suomen Malmi Oy conducted geophysical drillhole logging and optical imaging of the drillholes OL-KR51, OL-KR52, OL-KR52B, OL-KR53 and OL-KR53B at the Olkiluoto site in Eurajoki between November 2009 and February 2010. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and data processing. The report describes field operation, equipment as well as processing procedures and shows the obtained results and an analysis of their quality in the appendices. The raw and processed data are delivered digitally in WellCAD, PDF and Excel format. (orig.)

  11. β -decay study of 94Kr

    Science.gov (United States)

    Miernik, K.; Rykaczewski, K. P.; Grzywacz, R.; Gross, C. J.; Madurga, M.; Miller, D.; Stracener, D. W.; Batchelder, J. C.; Brewer, N. T.; Cartegni, L.; Fijałkowska, A.; Karny, M.; Korgul, A.; Królas, W.; Mazzocchi, C.; Mendez, A. J., II; Padgett, S. W.; Paulauskas, S. V.; Winger, J. A.; Wolińska-Cichocka, M.; Zganjar, E. F.

    2016-08-01

    β decay of neutron-rich nuclide 94Kr was reinvestigated by means of a high resolution on-line mass separator and β -γ spectroscopy. In total 22 γ -ray transitions were assigned to the decay of 94Kr, and a new isomeric state was identified. The new information allows us to build detailed levels systematics in a chain of odd-odd rubidium isotopes and draw conclusions on nuclear structure for some of the observed states. The discussed level structure affects the evolution of β -decay half-lives for neutron-rich selenium, krypton, and strontium isotopes.

  12. Structure of high spin states of 76Kr and 78Kr nuclei

    Indian Academy of Sciences (India)

    U R Jakhar; H L Yadav; A Ansari

    2005-12-01

    Following a fully self-consistent cranked Hartree-Fock-Bogoliubov (CHFB) approach with a pairing+quadrupole+hexadecapole model interaction Hamiltonian the structure of the yrast states of 76,78Kr nuclei is studied up to angular momentum = 24. Evolution of the shape with spin, and rotation alignment of proton as well as neutron 0g9/2 orbitals is investigated along with the inter- and intra-nucleus variations of the factors as a function of . We find that the shape of 78Kr remains prolate all through up to = 24, whereas 76Kr becomes triaxial beyond = 12.

  13. XENON IN THE PROTOPLANETARY DISK (PPD-Xe)

    Energy Technology Data Exchange (ETDEWEB)

    Marti, K.; Mathew, K. J., E-mail: kattathu.mathew@srs.gov [Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA (United States)

    2015-06-20

    Relationships among solar system Xe components as observed in the solar wind, in planetary atmospheres, and in meteorites are investigated using isotopic correlations. The term PPD-Xe is used for components inferred to have been present in the molecular cloud material that formed the protoplanetary disk (PPD). The evidence of the lack of simple relationships between terrestrial atmospheric Xe and solar or meteoritic components is confirmed. Xe isotopic correlations indicate a heterogeneous PPD composition with variable mixing ratios of the nucleosynthetic component Xe-HL. Solar Xe represents a bulk PPD component, and the isotopic abundances did not change from the time of incorporation into the interior of Mars through times of regolith implantations to the present.

  14. Hydration of Kr(aq) in Dilute and Concentrated Solutions.

    Science.gov (United States)

    Chaudhari, Mangesh I; Sabo, Dubravko; Pratt, Lawrence R; Rempe, Susan B

    2015-07-23

    Molecular dynamics simulations of water with both multi-Kr and single Kr atomic solutes are carried out to implement quasi-chemical theory evaluation of the hydration free energy of Kr(aq). This approach obtains free energy differences reflecting Kr-Kr interactions at higher concentrations. Those differences are negative changes in hydration free energies with increasing concentrations at constant pressure. The changes are due to a slight reduction of packing contributions in the higher concentration case. The observed Kr-Kr distributions, analyzed with the extrapolation procedure of Krüger et al., yield a modestly attractive osmotic second virial coefficient, B2 ≈ -60 cm(3)/mol. The thermodynamic analysis interconnecting these two approaches shows that they are closely consistent with each other, providing support for both approaches.

  15. Production and release rate of (37)Ar from the UT TRIGA Mark-II research reactor.

    Science.gov (United States)

    Johnson, Christine; Biegalski, Steven R; Artnak, Edward J; Moll, Ethan; Haas, Derek A; Lowrey, Justin D; Aalseth, Craig E; Seifert, Allen; Mace, Emily K; Woods, Vincent T; Humble, Paul

    2017-02-01

    Air samples were taken at various locations around The University of Texas at Austin's TRIGA Mark II research reactor and analyzed to determine the concentrations of (37)Ar, (41)Ar, and (133)Xe present. The measured ratio of (37)Ar/(41)Ar and historical records of (41)Ar releases were then utilized to estimate an annual average release rate of (37)Ar from the reactor facility. Using the calculated release rate, atmospheric transport modeling was performed in order to determine the potential impact of research reactor operations on nearby treaty verification activities. Results suggest that small research reactors (∼1 MWt) do not release (37)Ar in concentrations measurable by currently proposed OSI detection equipment.

  16. Kinetics modeling and interpretation of experimental results for XeF. Annual report, December 1985--November 1986

    Energy Technology Data Exchange (ETDEWEB)

    Salesky, E.T. [North East Research Associates, Inc., Woburn, MA (United States)

    1986-12-31

    In this report the author presents a detailed discussion of a computer model of the electron beam pumped XeF laser which was developed for Los Alamos National Laboratory during FY86. In its present form, it should provide useful modeling and scaling of XeF laser experiments currently of interest. Additional modifications will be required for long pulse (t{sub P}>5{mu}sec) simulations. The model includes all of the important energy transport processes which contribute to the formation and quenching of XeF in the B-state (upper laser level), X-state (lower laser level), C-state (which mixes with the B-state as a loss mechanism), and the unbound (repulsive) A-state to which the C-state decays. The gain of the B to X transition is resolved for the three most important laser (vibrational) lines: (0-3) at 353 nm, (0-2) and (1-4) at 351 nm. This report describes the kinetics model and computer code for electron beam pumped XeF lasers which use gas mixtures composed of argon (the buffer), xenon, and fluorine. The temperatures, energy flow, and chemistry (plasma and neutral) are calculated in a self-consistent manner; balances of energy, matter, and charge are tracked by the code and output with each print cycle. The model includes the time history of all of the important absorbers: Ar{sub 2}{sup +}, Xe{sub 2}{sup +}, Ar{sup *} and Xe{sup *} (s and p states), F{sub 2}, F{sup {minus}}, and Xe{sub 2}F{sup *}. Energy extraction in the form of lasing is computed using a modified Rigrod analysis which treats multiline lasing. This extraction model assumes a spatially uniform laser flux and is therefore a one dimensional (in time) treatment. The more general extraction model which treats non-uniform spatial effects (laser flux and pumping by a non-uniform electron beam) is being developed, and will be integrated with excimer model in the FY87 reporting period. The computer code was written in FORTRAN77 on a DEC MICROVAX II which uses the VAX/VMS operating system.

  17. RuMBa: a rule-model OPC for low MEEF 130-nm KrF lithography

    Science.gov (United States)

    Hsu, Stephen; Shi, Xuelong; Hsu, Chungwei Michael; Corcoran, Noel P.; Chen, J. Fung; Desai, Sunil; Sherrill, Micheal J.; Tseng, Y. C.; Chang, H. A.; Kao, J. F.; Tseng, Alex; Liu, WeiJyh; Chen, Anseime; Lin, Arthur; Kujten, Jan P.; Jacobs, Eric; Verhappen, Arjan

    2001-09-01

    For cost effective 130nm node manufacturing, it is prefer to use KrF binary chrome mask. To realize a production worth process for making random logic device, we need to effectively control mask error enhancement factor (MEEF) through pitch. In low k1 lithography, process parameters such as focus, lens aberration, linewidth, and line pitch, style of proximity correction (OPC), and resist process conditions, etc., all impact MEEF. We show a powerful RuMBa OPC method that can reduce MEEF to an acceptable level (close to 1(using KrF resist process. We believe that RuMBa OPC method can be further extended for sub 100nm ArF process. In wafer printing experiment, we have designed a new style of LineSweeper reticles for our lithography process optimization. Both simulated and printed wafer CD data were used to calculate the overlapped process window along with respective MEEF. These are the metric we used to assess the 130nm process performance. Using RuMBa OPC, we are able to achieve overlapped process window that is sufficient for 130nm gate mask process. The CD through pitch calibration is critical for an accurate model-based correct at location where OPC rule cannot cover. A high accuracy CD through pitch calibration methodology is developed for model calibration. In this paper, we have compared the 130nm performance using KrF binary mask, KrF 6% attenuated PSM, and ArF binary mask.

  18. Kr atoms and their clustering in zeolite A

    CERN Document Server

    Lim, W T; Jung, K J; Heo, N H

    2001-01-01

    The positions of Kr atoms encapsulated in the molecular-dimensioned cavities of fully dehydrated zeolite A of unit-cell composition Cs sub 3 Na sub 8 HSi sub 1 sub 2 Al sub 1 sub 2 O sub 4 sub 8 (Cs sub 3 -A) have been determined. Cs sub 3 -A was exposed to 1025 atm of krypton gas at 400 .deg. C for four days, followed by cooling at pressure to encapsulate Kr atoms. The resulting crystal structure of Cs sub 3 -A(6Kr) (a=12.247(2) A, R sub 1 =0.078, and R sub 2 =0.085) has been determined by single-crystal X-ray diffraction techniques in the cubic space group Pm3m at 21(1) .deg. C and 1 atm. In the crystal structure of Cs sub 3 -A(6Kr), six Kr atoms per unit cell are distributed over three crystallographically distinct positions: each unit cell contains one Kr atom at Kr(1) on a threefold axis in the sodalite unit, three at Kr(2) opposite four-rings in the large cavity , and two at Kr(3) on threefold axes in the large cavity . Relatively strong interactions of Kr atoms at Kr(1) and Kr(3) with Na sup + ions of ...

  19. Monitoring 85Kr at China Reprocessing and Radiochemistry Laboratory

    Institute of Scientific and Technical Information of China (English)

    LV; Xue-sheng; LIU; Guo-rong; WANG; Chen; XU; Chang-kun; ZHOU; Hao

    2015-01-01

    85Kr is a long life fission product and a noble gas and one of the main target radionuclides in monitoring environment for the reprocessing plant.During the course of the spent fuel elements are dissolved,85Kr is released and part of these 85Kr will be let out through the stack after

  20. Overlevelse kræver indsigt

    DEFF Research Database (Denmark)

    Grunert, Klaus G.

    1998-01-01

    koncentreret detailhandel prøver at sætte dagsorden for konkurrencen. Når konkurrencebetingelser er under forandring skal virksomhederne også forandre sig, hvis de stadigvæk vil være med fremover. I denne forbindelse taler man tit om kompetenceudvikling - de nye vilkår kræver, at virksomhederne tilpasser deres...

  1. Alternativ behandling og kræft

    DEFF Research Database (Denmark)

    Lunde, Anita; Johannessen, Helle

    2010-01-01

    Baggrund: Interessen for komplementær og alternativ behandling (KAB) er stadig stigende, og der kan dokumenteres et større forbrug af KAB blandt kræftpatienter. Patienter anvender primært KAB som supplement til deres konventionelle behandling, og mange så gerne KAB som en integreret praksis. Fler...

  2. Results of sampling and analysis of groundwater from multi-packered boreholes OL-KR1, OL-KR3, OL-KR5, OL-KR9, OL-KR11 and OL-KR12 at Olkiluoto, Eurajoki, in 2004

    Energy Technology Data Exchange (ETDEWEB)

    Hirvonen, H. [Teollisuuden Voima Oyj, Eurajoki (Finland); Hatanpaeae, E. [lnsinoeoeritoimisto Paavo Ristola Oy, Hollola (Finland)

    2005-12-15

    Nine groundwater samples were collected at Olkiluoto from deep multi-packered boreholes OL-KR1, OL-KR3, OL-KR5, OL-KR9, OL-KR11 and OL-KR12 between spring 2004 and the beginning of 2005. The aim of the ground water sampling was to get information for the basis of the monitoring program (OMO) during ONKALO construction. Sampling sections were mainly chosen so that the results of the chemical analyses from earlier studies could be used for comparison. This study presents the sampling methods and the results of the laboratory analyses of groundwater samples from the deep multi-packered boreholes OL-KR1 (151.2-156.8 m, 311.2-336.8 m and 524.4-528.4 m), OL-KR3 (242.6-253.2 m), OL-KR5 (277.2-284.6 m and 457.2-476.2 m), OL-KR9 (468.2-482.2 m), OL-KR11 (597.5-628.1 m) and OLKR12 (363-368 m). The analytical results of the groundwater samplings are compared to earlier analytical results. According to Davis and De Wiest's (1967) classification, the collected groundwater samples represent either the borehole water type Na-Cl (OL-KR1/T/151.2-156.8 m, OLK-R1/ T/311.2-336.8 m, OL-KR3/T/242.6-253.2 m, OL-KR5/T/277.2-284.6 m, OL-KR11/ T/597.5-628.1 m and OL-KR12/T/363-368 m) or Na-Ca-Cl (OL-KR1/T/524.4- 528.4 m, OL-KR5/T/457.2-476.2 m and OL-KR9/T/468.2-482.2 m). The groundwater samples from OL-KR1/T/151.2-156.8 m, OL-KR3/T/242.6- 253.2 m, OL-KR3/T/242.6-253.2 m, OL-KR5/T/277.2-284.2 m, OL-KR11/T/597.5-628.1 m and OL-KR12/T/363-368 m were brackish (1000 mg/L < TDS < 10000 mg/L) according to Davis's (1964) TDS classification. Other samples (OL-KR1/T/524.4-528.4 m, OL-KR5/ T/457.2-476.2 m and OL-KR9/T/468.2-482.2 m), were saline (TDS> 10000 mg/L). Comparison of analytical results of the samples to earlier results shows that some changes were seen between samplings done at the different times. Only the groundwater sampled from OL-KR1/T/311.2-336.8 m had significant changes in its chemical composition during the reference period, but also in OL-KR1/T/524.4-528.4 m, OL-KR5/ T

  3. Clinical utility and reliability of sup(81m)Kr SPECT images applied to posterior circulation

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizawa, Takashi; Kikuchi, Haruhiko; Karasawa, Jun (National Cardiovascular Center, Suita, Osaka (Japan))

    1984-08-01

    The instrument used in this study has a sensitivity of 28,000 counts/mCi/cm/sup 3/ for sup(99m)Tc and a spatial resolution of approximately 20mm full width at a half-maximum. The tomographic images were obtained by the continuous infusion of sup(81m)Kr at the base of the ascending aorta. Material was subsequently studied in 49 cases that met the conditions of: 1) obstructive vertebrobasilar system lesions (8 cases), 2) no ischemic cerebrovascular diseases (10), or 3) ischemic cerebrovascular disorders in anterior circulation (31). The reproducibility, as studied in 20 cases, was satisfactory. 6 cases were compared with a stable Xe CT CBF map that had regional depressions similar to those of the sup(81m)Kr SPECT images. In the 2nd group, 8 of the 10 cases showed a mild laterality on cerebellar perfusion images obtained by SPECT, as did 29 of the 31 in the 3rd group; among them, 2 cases with a recently completed stroke revealed a marked depression in the ipsilateral cerebellar hemisphere to the side of the hemiplegia. Cases of the lst group showed generally depressed perfusion images of the brain stem or cerebellum, and the low-density areas of X-ray CT were comparable to the lower perfusional regions on SPECT. The authors concluded that posterior perfusion images obtained by sup(81m)Kr SPECT were affected by occlusive vertebrobasilar-system lesions as well as by carotid-system lesions and cerebellar functions, and that this method for evaluating hemodynamics will be of much more clinical use in repeated studies to demonstrate the changes in posterior ciculation in course or by some loadings with subclinical characteristics, for this paper includes the first report on cerebellar functional images, though it is restricted by the low-spatial resolution from defining the architecture of the posterior fossa in detail.

  4. HP-Xe to go: Storage and Transportation of Hyperpolarized 129-Xe

    NARCIS (Netherlands)

    Repetto, M.; Zimmer, S.; Almendinger, F.; Blümler, P.; Doll, M.; Grasdijk, J.O.; Heil, W.; Jungmann, K.; Karpuk, S.; Krause, H.-J.; Offenhaeusser, A.; Schmidt, U.; Sobolev, Y.; Willmann, L.

    2016-01-01

    Recently the spin-lattice relaxation time T1 of hyperpolarized (HP)-129Xe was significantly improved by using uncoated and Rb-free storage vessels of GE180 glass. For these cells, a simple procedure was established to obtain reproducible wall relaxation times of about 18 h. Then the limiting relaxat

  5. Liquid-Xe detector for contraband detection

    Energy Technology Data Exchange (ETDEWEB)

    Vartsky, D., E-mail: david.vartsky@weizmann.ac.il [Weizmann Institute of Science, Rehovot 76100 (Israel); Israelashvili, I. [Weizmann Institute of Science, Rehovot 76100 (Israel); Nuclear Research Center of Negev (NRCN), Beer-Sheva 9001 (Israel); Cortesi, M. [National Superconducting Cyclotron Laboratory, East Lansing 48823, MI (United States); Arazi, L.; Coimbra, A.E.; Moleri, L.; Erdal, E.; Bar, D.; Rappaport, M.; Shchemelinin, S. [Weizmann Institute of Science, Rehovot 76100 (Israel); Caspi, E.N. [Nuclear Research Center of Negev (NRCN), Beer-Sheva 9001 (Israel); Aviv, O. [Soreq NRC, Yavne 81800 (Israel); Breskin, A. [Weizmann Institute of Science, Rehovot 76100 (Israel)

    2016-07-11

    We describe progress made with a liquid-Xe (LXe) detector coupled to a gaseous photomultiplier (GPM), for combined imaging and spectroscopy of fast neutrons and gamma-rays in the MeV range. The purpose of this detector is to enable the detection of hidden explosives and fissile materials in cargo and containers. The expected position resolution is about 2 m and 3.5 mm for fast neutrons and gamma-rays, respectively. Experimental results obtained using an {sup 241}Am source yielded energy and time resolutions of 11% and 1.2 ns RMS, respectively. Initial results obtained with the position-sensitive GPM are presented.

  6. Negative correlation of 129I/127I and 129Xe/132Xe: product of closed system evolution or evidence of a mixed component.

    Science.gov (United States)

    Gilmour, J. D.; Whitby, J. A.; Turner, G.

    2001-10-01

    Anti-correlation of initial iodine ratios with trapped 129Xe/132Xe ratios has been interpreted as resulting from 129I decay to 129Xe in a closed system. However, many of the 129Xe/132Xe ratios that contribute to the anti-correlations are lower than 1.04, the value characteristic of major solar system reservoirs; 129I decay cannot lead to a decrease in this ratio. We offer an alternative explanation for the anti-correlations, based on trapped iodine and xenon components similar to those observed in Nakhla, that does not require the existence of components with 129Xe/132Xe lower than solar.

  7. ArArCALC—software for 40Ar/ 39Ar age calculations

    Science.gov (United States)

    Koppers, Anthony A. P.

    2002-06-01

    ArArCALC is a Microsoft Excel ® 97-2000-XP application for performing calculations in 40Ar/ 39Ar geochronology. It is coded in Visual Basic for Applications and can be used under the Windows ® 95/98/NT/2000/ME/XP operating systems. ArArCALC provides an easy-to-use graphical interface for the calculation of age plateaus, total fusion ages and isochrons following the regression of 40Ar/ 39Ar mass spectrometry data. Results are stored in single Excel workbooks including nine different data tables and four different diagrams. Analytical, internal and external errors are calculated based on error propagation of all input parameters, analytical data and applied corrections. Finally, the age calculation results can be recalibrated with reference to the primary K-Ar standards (e.g. GA-1550, MMhb-1) in order to obtain more consistent absolute40Ar/ 39Ar age determinations. ArArCALC is distributed as freeware.

  8. Kr photoionized plasma induced by intense extreme ultraviolet pulses

    Science.gov (United States)

    Bartnik, A.; Wachulak, P.; Fiedorowicz, H.; Skrzeczanowski, W.

    2016-04-01

    Irradiation of any gas with an intense EUV (extreme ultraviolet) radiation beam can result in creation of photoionized plasmas. The parameters of such plasmas can be significantly different when compared with those of the laser produced plasmas (LPP) or discharge plasmas. In this work, the photoionized plasmas were created in a krypton gas irradiated using an LPP EUV source operating at a 10 Hz repetition rate. The Kr gas was injected into the vacuum chamber synchronously with the EUV radiation pulses. The EUV beam was focused onto a Kr gas stream using an axisymmetrical ellipsoidal collector. The resulting low temperature Kr plasmas emitted electromagnetic radiation in the wide spectral range. The emission spectra were measured either in the EUV or an optical range. The EUV spectrum was dominated by emission lines originating from Kr III and Kr IV ions, and the UV/VIS spectra were composed from Kr II and Kr I lines. The spectral lines recorded in EUV, UV, and VIS ranges were used for the construction of Boltzmann plots to be used for the estimation of the electron temperature. It was shown that for the lowest Kr III and Kr IV levels, the local thermodynamic equilibrium (LTE) conditions were not fulfilled. The electron temperature was thus estimated based on Kr II and Kr I species where the partial LTE conditions could be expected.

  9. Hydration of Kr(aq) in dilute and concentrated solutions

    CERN Document Server

    Chaudhari, M I; Pratt, L R; Rempe, S B

    2014-01-01

    Molecular dynamics simulations of water with both multi-Kr and single Kr atomic solutes are carried out to implement quasi-chemical theory evaluation of the hydration free energy of Kr(aq). This approach also obtains free energy differences reflecting Kr-Kr interactions at higher concentrations. Those differences are negative (though small) changes in hydration free energies with increasing concentrations at constant pressure. The changes are due to a slight reduction of packing contributions in the higher concentration case. The observed Kr-Kr distributions, analyzed through a delicate $k\\rightarrow 0$ extrapolation, yield positive (though small) values for the osmotic second virial coefficient, $B_2$. A standard thermodynamic analysis interconnecting these two approaches shows that they can be consistent with each other.

  10. Electric dipole moment of ^{129}Xe atom

    CERN Document Server

    Singh, Yashpal; Das, B P

    2013-01-01

    The parity (P) and time-reversal (T) odd coupling constant associated with the tensor-pseudotensor (T-PT) electron-nucleus interaction and the nuclear Schiff moment (NSM) have been determined by combining the result of the measurement of the electric dipole moment (EDM) of ^{129}Xe atom and calculations based on the relativistic coupled-cluster (RCC) theory. Calculations using various relativistic many-body methods have been performed at different levels of approximation. The accuracies of these calculations are estimated by comparing the results of the calculated dipole polarizability of the ground state of the above atom with the most precise available experimental data. The non-linear terms that arise in the RCC theory at the singles and doubles approximation (CCSD method) were found to be crucial for achieving high accuracy in the calculations. Our results for the ^{129}Xe EDM due to the odd T-PT interaction and the NSM are, respectively, d_A=0.501 x 10^{-20} C_T |e|cm and d_A=0.336 x 10^{-17} S/(|e| fm^...

  11. Comparative analysis of spectra of the background of the proportional counter filled with Kr, enriched in Kr-78, and with Kr of natural content

    OpenAIRE

    Gavriljuk, Yu. M.; Gavrin, V. N.; Gangapshev, A. M.; Kazalov, V. V.; Kuzminov, V. V.; Panasenko, S. I.; Ratkevich, S. S.

    2007-01-01

    The results of the experiment searching for 2K-capture with large low-background proportional counter are presented. The comparison of spectra of the background of the proportional counter filled with Kr enriched in $^{78}$Kr (8400 hr) and with natural Kr (3039 hr) is given. A new limit on the half-life of $^{78}$Kr with regard to 2K-capture, T$_{1/2}\\geq2.0\\cdot10^{21}$ yrs (95% C.L.) has been obtained.

  12. Shell Model Estimate of Electric Dipole Moments for Xe Isotopes

    Science.gov (United States)

    Teruya, Eri; Yoshinaga, Naotaka; Higashiyama, Koji

    The nuclear Schiff moments of Xe isotopes which induce electric dipole moments of neutral Xe atoms is theoretically estimated. Parity and time-reversal violating two-body nuclear interactions are assumed. The nuclear wave functions are calculated in terms of the nuclear shell model. Influences of core excitations on the Schiff moments in addition to the over-shell excitations are discussed.

  13. Simulations of Xe and U diffusion in UO2

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Anders D. [Los Alamos National Laboratory; Vyas, Shyam [Los Alamos National Laboratory; Tonks, Michael R. [Idaho National Laboratory; Casillas, Luis [Los Alamos National Laboratory; Uberuaga, Blas P. [Los Alamos National Laboratory; Millett, Paul [Idaho National Laboratory

    2012-09-10

    Diffusion of xenon (Xe) and uranium (U) in UO{sub 2} is controlled by vacancy mechanisms and under irradiation the formation of mobile vacancy clusters is important. Based on the vacancy and cluster diffusion mechanisms established from density functional theory (DFT) calculations, we derive continuum thermodynamic and diffusion models for Xe and U in UO{sub 2}. In order to capture the effects of irradiation, vacancies (Va) are explicitly coupled to the Xe and U dynamics. Segregation of defects to grain boundaries in UO{sub 2} is described by combining the bulk diffusion model with models of the interaction between Xe atoms and vacancies with grain boundaries, which were derived from atomistic calculations. The diffusion and segregation models were implemented in the MOOSE-Bison-Marmot (MBM) finite element (FEM) framework and the Xe/U redistribution was simulated for a few simple microstructures.

  14. Innovativ produktudvikling kræver kursskifte

    DEFF Research Database (Denmark)

    McAloone, Tim C.

    2007-01-01

    Innovativ produktudvikling kræver kursskifte Danske virksomheder har brug for nye metoder og værktøjer til produktudvikling Af Tim McAloone redaktion@ing.dk, fredag 04. maj 2007 kl. 00:00 Den industrielle arena i Europa er under stærk forandring. Virksomhederne står over for en række strategiske...

  15. Krāsas un atmosfēra Edgara Alana Po dzejā

    OpenAIRE

    Kļimova, Kristīna

    2009-01-01

    Bakalaura darba tēma ir krāsas un noskaņa Edgar Allana Po dzejā. Pētījuma uzdevums ir noteikt biežāk lietojamos tēlainās izteiksmes līdzekļus un krāsas Edgara Po dzejā, turklāt identificēt gaisotni un noskaņu šajos darbos. Darba autore ir veikusi pētījumu balstoties uz praktiskām un teorētiskām zināšanām. Teorētiskā daļa iztirzā tāda veida problēmas kā: tēlainās izteiksmes līdzekļu būtību, simbolu un simbolsisko krāsu izmantošana literatūrā, ka arī to nozīmi Edgara Allana Po dzejā, un cit...

  16. The thermal neutron scattering cross section of {sup 86}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Terburg, B.P.

    1992-05-01

    The availability of 27 1 STP krypton-86 gas, an isotope with unknown thermal neutron scattering cross section, was an excellent occasion to determine the (bound atom) scattering cross section and its coherent part by application of the neutron transmission method and neutron interferometry. The transmission method was applied in a diffractometer, a Larmor spectrometer and a TOF-spectrometer. In addition to {sup 86}Kr also natural krypton ({sup n}Kr) was used for sample in the diffractometer. The diffractometer measurements result in bound atom scattering cross sections {sigma}{sub s}=8.92(46) b for {sup 86}Kr and {sigma}{sub s}=7.08(95) b for {sup n}Kr. The Larmor transmission measurements lead to a final result {sigma}{sub s}=8.44(9) b for {sup 86}Kr. In the TOF-spectrometer the wavelength-dependent total cross section of water was determined. Coherent neutron scattering lengths were determined using the neutron interferometry method with a skew symmetric neutron interferometer. Scans with {sup 86}Kr and {sup n}Kr led to b{sub c}=8.07(26) fm for {sup 86}Kr and 7.72(33) fm for {sup n}Kr, corresponding to coherent scattering cross sections {sigma}{sub c}=8.18(53) b and 7.49(64) b respectively. Due to the large errors in the bound atom scattering cross section and coherent scattering cross section of {sup 86}Kr and {sup n}Kr, the incoherent cross section of both gases, {sigma}{sub i} = 0 within its inaccuracy, {sigma}{sub i}=0.26(54) b for {sup 86}Kr and {sigma}{sub i}=0.41(1.15) b for {sup n}Kr. (orig.).

  17. Evaluation of {sup 133}Xe and {sup 133}Xe{sup m} decay data

    Energy Technology Data Exchange (ETDEWEB)

    Galan, M. [Laboratorio de Metrologia de Radiaciones Ionizantes, CIEMAT, Av. Complutense 22, 28040 Madrid (Spain)], E-mail: monica.galan@ciemat.es

    2009-01-15

    This paper presents the decay data evaluation of {sup 133}Xe and {sup 133}Xe{sup m}, which includes the most recent available data, such as half-life results and gamma-ray intensities that have not been considered in previous evaluations. The adopted internal conversion coefficients (ICC) have been calculated using the 'Frozen Orbital' approximation and are compared here to recent measured values. Recent Q-value tabulations, recommended gamma-ray energies for calibrations, as well as new evaluated gamma-ray intensities for the 81- and 233-keV lines (37.0 (3)% and 10.16 (13)%, respectively) are also presented in this evaluation. Atomic radiation emission probabilities (X-ray and Auger electron) associated with nuclear radiations have been deduced and also included in this work.

  18. Kr-85 signatures for various plutonium production schemes

    Energy Technology Data Exchange (ETDEWEB)

    Stanoszek, Paul [Carl Friedrich von Weizsaecker-Centre for Science and Peace Research (Germany)

    2009-07-01

    Kr-85 is considered to be the best atmospheric indicator of unreported weapon-grade material production. This fact is based on the half-life of 10.76 years of Kr-85 and its chemical inactivity, which makes it even detectable after extended periods of cooling time. Kr-85 is produced as fission product during nuclear reactor operation and remains in the fuel until reprocessing starts. In order to determine the detectability of plutonium production the Kr-85 source term has to be assessed. The important issue of this presentation is the question on the minimum signal that an inspector can expect under the assumption that a proliferator minimizes his Kr-85 generation in order to circumvent a Kr-85 detection. A further assumption is that for nuclear weapon production a burn-up of typically around 2 MWd/kg is used. In addition, if clandestine plutonium production takes place, the source term might be used to estimate the amount of separated plutonium. The methodology of this study is based on a linkage between MCNPX and MATLAB. All results for actinide concentrations and Kr-85 are evaluated for different enrichments of U-235 and compared to known literature data. The Kr-85 source term per kilogram plutonium depends on the enrichments. As a result the lowest Kr-85 source term is found for depleted uranium.

  19. Intense vacuum ultraviolet and infrared scintillation of liquid Ar-Xe mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Neumeier, Alexander; Oberauer, Lothar; Potzel, Walter; Roth, Sabine; Schoenert, Stefan [Physik-Department E15, Technische Universitaet Muenchen, James-Franck-Strasse 1, 85748 Garching (Germany); Dandl, Thomas; Heindl, Thomas; Himpsl, Andreas; Wieser, Jochen; Ulrich, Andreas [Physik-Department E12, Technische Universitaet Muenchen, James-Franck-Strasse 1, 85748 Garching (Germany)

    2015-07-01

    Electron-beam excited xenon-doped liquid argon has two intense and well separated scintillation signals in the vacuum ultraviolet (VUV) and in the near-infrared (NIR) wavelength region. Wavelength resolved scintillation spectra of liquid argon-mixtures are presented in a wide wavelength range from 115 to 3500 nm. The most intense emission features in the VUV and the NIR were measured time resolved (ns resolution) under pulsed electron-beam excitation. In this talk, the different detection principles, the results and a possible application in a novel detector concept are briefly discussed.

  20. Intense Vacuum-Ultraviolet and Infrared Scintillation of Liquid Ar-Xe Mixtures

    CERN Document Server

    Neumeier, A; Heindl, T; Himpsl, A; Oberauer, L; Potzel, W; Roth, S; Schönert, S; Wieser, J; Ulrich, A

    2015-01-01

    Vacuum ultraviolet light emission from xenon-doped liquid argon is described in the context of liquid noble gas particle detectors. Xenon concentrations in liquid argon from 0.1 ppm to 1000 ppm were studied. The energy transfer from the second excimer continuum of argon ($\\sim$127 nm) to the second excimer continuum of xenon ($\\sim$174 nm) is observed by recording optical emission spectra. The transfer almost saturates at a xenon concentration of $\\sim$10 ppm for which, in addition, an intense emission in the infrared at a peak wavelength of 1.17 $\\mu$m with (13000$\\pm$4000) photons per MeV deposited by electrons had been found. The corresponding value for the VUV emission at a peak wavelength of 174 nm (second excimer continuum of xenon) is determined to be (20000$\\pm$6000) photons per MeV electron energy deposited. Under these excitation conditions pure liquid argon emits (22000$\\pm$3000) photons per MeV electron energy deposited at a peak wavelength of 127nm. An electron-beam induced emission spectrum for ...

  1. Evolutions of Molecular Oxygen Formation and Sodium Migration in Xe Ion Irradiated Borosilicate Glasses

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Liang; Zhang, Duofei F.; Lv, Peng; Zhang, Jiandong; Du, Xing; Yuan, Wei; Nan, Shuai; Zhu, Zihua; Wang, Tieshan

    2016-07-23

    The modifications of a commercial borosilicate glass induced by Xe ion irradiation have been studied by Raman spectroscopy and ToF-SIMS depth profiling. A decrease in the average Si–O–Si angle, an increase in the population of three-membered rings and an increase of the glass polymerization are evidenced. The molecular oxygen appears in the irradiated glasses after the irradiation fluence reaches approximately 1015 ions/cm2. The O2 concentration decreaseswith the depth of irradiated glass at the ion fluence of 2 × 1016 ions/cm2. A sodiumdepleted layer at the surface and a depleted zone at around the penetration depth of 5 MeV Xe ions are observed. The thickness of the sodium depleted layer increases with the irradiation fluence. Moreover, comparing with previous results after electron and Ar ion irradiation, it can be concluded that the nuclear energy deposition can partially inhibit the formation of molecular oxygen and increase the threshold value of electron energy deposition for the molecular oxygen formation.

  2. Recent improvements in transport and application of hyperpolarized Xe-129

    Energy Technology Data Exchange (ETDEWEB)

    Repetto, Maricel; Heil, Werner; Bluemler, Peter [Johannes Gutenberg University, Institute of Physics, Mainz (Germany); Duewel, Mathis; Spiess, Hans W.; Muennemann, Kerstin [Max Planck Institute for Polymer Research, Mainz (Germany)

    2011-07-01

    Hyperpolarized (HP) Xe-129 has numerous applications in medicine and fundamental physics. For separating HP Xe-129 from other gases used in the hyperpolarization process, it can be accumulated at 77 K. The conditions of this process must be carefully evaluated in order to minimize polarization losses. Different devices and results for this separation process are presented. Additionally, HP Xe-129 must be transported to other sites (e.g. clinics). Therefore, the relaxation time, T{sub 1}, must be kept as long as possible. Different strategies (e.g. admixing of gases and low-field storage) to achieve this goal are presented together with suitable home-build instrumentation to determine T{sub 1}. Finally, the application to the patient must be realized in a rapid and biocompatible way. Here we found a very elegant solution by using oxygenation membranes, which dissolve Xe instantaneously and without foaming in any suitable carrier liquid or even blood.

  3. Positron annihilation Doppler broadening study of Xe-implanted aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Yu, R.S., E-mail: yursh@ihep.ac.cn [Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, No. 19 Yuquan Lu, Beijing 100049 (China); Maekawa, M.; Kawasuso, A. [Japan Atomic Energy Agency, Advanced Science Research Center, Watanuki 1233, Takasaki, Gunma 370-1292 (Japan); Wang, B.Y.; Wei, L. [Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, No. 19 Yuquan Lu, Beijing 100049 (China)

    2013-10-01

    Positron annihilation Doppler broadening measurements were conducted to characterize information of defects in 380 keV Xe{sup +}-implanted aluminum upon thermal annealing at temperatures ranging from 100 to 600 °C. The results suggest a broad distribution in the depth of vacancy-type defects in all the as-implanted samples. Meanwhile, with an increase in implantation dose the defect-rich region shifts toward the sample surface. It was found that increasing the annealing temperature triggers surface-directed migration and coalescence of vacancy and Xe{sub n}V{sub m} clusters in samples with implantation doses of 1E15 and 1E16 Xe{sup +}cm{sup −2}. In the sample implanted with a high dose of 1E17 Xe{sup +}cm{sup −2}, positron annihilation revealed a decomposition and even elimination of such defects under post-implantation annealing treatment.

  4. Observation of {sup 135}Xe with the PNNL ARSA System

    Energy Technology Data Exchange (ETDEWEB)

    Reeder, P.L.; Bowyer, T.W.; Abel, K.H. [and others

    1997-08-01

    The automated radioxenon sampler-analyzer (ARSA) developed by PNNL and with funding and support form the DOE NN-20 CTBT research and development program, observed 9.1-hr {sup 135}Xe in a sample of New York City air obtained on April 4th, 1997. The report below briefly describes the ARSA system and the first ever reported measurement of the short-lived {sup 135}Xe from an automated radioxenon system.

  5. Testing the Spectral Deconvolution Algorithm Tool (SDAT) with Xe Spectra

    Science.gov (United States)

    2007-09-01

    import spectra, analyze the data for Xe concentrations, and graphically display the results. This tool has been tested with data generated via MCNPX ...characteristics, e.g., the sample Xe gas volume from which the total sampled atmospheric volume is calculated . The sample histogram will be deconvolved...SDAT window. It contains the concentration coefficients and errors of each radioxenon of interest calculated with and without the use of data

  6. In vitro metabolism of a novel PPAR gamma agonist, KR-62980, and its stereoisomer, KR-63198, in human liver microsomes and by recombinant cytochrome P450s.

    Science.gov (United States)

    Kim, K-B; Seo, K-A; Yoon, Y-J; Bae, M-A; Cheon, H G; Shin, J-G; Liu, K-H

    2008-09-01

    1. KR-62980 and its stereoisomer KR-63198 are novel and selective peroxisome proliferator-activated receptor gamma (PPAR gamma) modulators with activity profiles different from that of rosiglitazone. This study was performed to identify the major metabolic pathways for KR-62980 and KR-63198 in human liver microsomes. 2. Human liver microsomal incubation of KR-62980 and KR-63198 in the presence of a beta-nicotinamide adenine dinucleotide phosphate (NADPH)-generating system resulted in hydroxy metabolite formation. In addition, the specific cytochrome P450s (CYPs) responsible for KR-62980 and KR-63198 hydroxylation were identified by using a combination of chemical inhibition in human liver microsomes and metabolism by recombinant P450s. It is shown that CYP1A2, CYP2D6, CYP3A4, and CYP3A5 are the predominant enzymes in the hydroxylation of KR-62980 and KR-63198. 3. The intrinsic clearance through hydroxylation was consistently and significantly higher for KR-62980 than for KR-63198, indicating metabolic stereoselectivity (CL(int) of 0.012 +/- 0.001 versus 0.004 +/- 0.001 microl min(-1) pmol(-1) P450, respectively). 4. In a drug-drug interaction study, KR-62980 and KR-63198 had no effect on the activities of the P450s tested (IC(50) > 50 microM), suggesting that in clinical interactions between KR-62980 and KR-63198 the P450s tested would not be expected.

  7. Relativistic Coulomb excitation of {sup 88}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Moschner, Kevin; Blazhev, Andrey; Jolie, Jan; Warr, Nigel; Wendt, Andreas [IKP, Universitaet zu Koeln, 50937 Koeln (Germany); Collaboration: PreSPEC-Collaboration

    2015-07-01

    Within the scope of the PreSPEC campaign we performed a Coulomb-excitation experiment to determine absolute E2 transition strengths to 2{sup +} states in the radioactive nucleus {sup 88}Kr. The aim of our studies was to identify the one quadruple-phonon mixed-symmetry 2{sub MS}{sup +} state in order to extend our knowledge on these states to lighter N = 52 isotones and to track their evolution over different proton shells. The investigated ions were provided through projectile fission of a 650 MeV {sup 238}U beam on a primary target consisting of 0.6 g/cm{sup 2} {sup 9}Be and subsequent separation and identification of the reaction products via the FRS at GSI. The secondary target consisted of 0.4 g/cm{sup 2} {sup 197}Au. De-exciting γ radiation was detected by the PreSPEC array, consisting of 15 EUROBALL Cluster detectors. The Lund-York-Cologne-CAlorimeter LYCCA was used for particle identification after the secondary target. Absolute transition strengths of the transitions depopulating the 2{sup +}{sub 3} state in {sup 88}Kr which suggest the mixed symmetric character of this state are presented and discussed within the systematics of the N = 52 isotones.

  8. 7 CFR 29.1081 - Variegated red or scorched (KR).

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Variegated red or scorched (KR). 29.1081 Section 29.1081 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards..., 13, 14 and Foreign Type 92) § 29.1081 Variegated red or scorched (KR). A red discoloration...

  9. Role of the entrance channel on the product internal energy distribution in the reaction: (Xe-Cl 2) * → XeCl * + Cl

    Science.gov (United States)

    Boivineau, M.; Le Calvé, J.; Castex, M. C.; Jouvet, C.

    1986-08-01

    The Xe-Cl 2 van der Waals complex formed in a supersonic expansion is excited by a two-photon process at 297.5 nm. The XeCl ∗ fragment obtained is vibrationally cold. This result is discussed and compared with those of the Xe ∗ + Cl 2 reaction and laser-assisted collision.

  10. Calibration of a Liquid Xenon Detector with Kr-83m

    CERN Document Server

    Kastens, L W; Manzur, A; McKinsey, D N

    2009-01-01

    We report the preparation of a Kr-83m source and its subsequent use in calibrating a liquid xenon detector. Kr-83m atoms were produced through the decay of Rb-83 atoms trapped in zeolite molecular sieve and were then introduced into liquid xenon. Decaying Kr-83m nuclei were detected through liquid xenon scintillation. Conversion electrons with energies of 9.4 keV and 32.1 keV from the decay of Kr-83m were both observed. This calibration source will allow the characterization of the scintillation and ionization response of noble liquid detectors at low energies, highly valuable for the search for WIMP dark matter. Kr-83m may also be useful for measuring fluid flow dynamics, both to understand purification in noble liquid-based particle detectors, as well as for studies of classical and quantum turbulence in superfluid helium.

  11. Self-controlled KR schedules: does repetition order matter?

    Science.gov (United States)

    Patterson, Jae T; Carter, Michael J; Hansen, Steve

    2013-08-01

    The impact of an experimenter-defined repetition schedule on the utility of a self-controlled KR context during motor skill acquisition was examined. Participants were required to learn three novel spatial-temporal tasks in either a random or blocked repetition schedule with or without the opportunity to control their KR. Results from the retention period showed that participants provided control over their KR schedule in a random repetition schedule demonstrated superior learning. However, performance measures from the transfer test showed that, independent of repetition schedule, learners provided the opportunity to control their KR schedule demonstrated superior transfer performance compared to their yoked counterparts. The dissociated impact of repetition schedule and self-controlled KR schedules on retention and transfer is discussed.

  12. New neutron-deficient isotopes from 78Kr fragmentation

    Science.gov (United States)

    Blank, B.; Goigoux, T.; Ascher, P.; Gerbaux, M.; Giovinazzo, J.; Grévy, S.; Kurtukian Nieto, T.; Magron, C.; Agramunt, J.; Algora, A.; Guadilla, V.; Montaner-Piza, A.; Morales, A. I.; Orrigo, S. E. A.; Rubio, B.; Ahn, D. S.; Doornenbal, P.; Fukuda, N.; Inabe, N.; Kiss, G.; Kubo, T.; Kubono, S.; Nishimura, S.; Phong, V. H.; Sakurai, H.; Shimizu, Y.; Söderström, P.-A.; Sumikama, T.; Suzuki, H.; Takeda, H.; Wu, J.; Fujita, Y.; Tanaka, M.; Gelletly, W.; Aguilera, P.; Molina, F.; Diel, F.; Lubos, D.; de Angelis, G.; Napoli, D.; Borcea, C.; Boso, A.; Cakirli, R. B.; Ganioglu, E.; Chiba, J.; Nishimura, D.; Oikawa, H.; Takei, Y.; Yagi, S.; Wimmer, K.; de France, G.; Go, S.

    2016-06-01

    In an experiment with the RIKEN projectile fragment separator called BigRIPS at the RIKEN Nishina Center, the fragmentation of a 78Kr beam allowed the observation of new neutron-deficient isotopes at the proton drip line. Clean identification spectra could be produced and 63Se,67Kr, and 68Kr were identified for the first time. In addition, 59Ge was also observed. Three of these isotopes, 59Ge,63Se, and 67Kr, are potential candidates for ground-state two-proton radioactivity. In addition, the isotopes 58Ge,62Se, and 66Kr were also sought but without success. The present experiment also allowed the determination of production cross sections for some of the most exotic isotopes. These measurements confirm the trend already observed that the empirical parametrization of fragmentation cross sections, EPAX, significantly overestimates experimental cross sections in this mass region.

  13. New neutron-deficient isotopes from $^{78}$Kr fragmentation

    CERN Document Server

    Blank, B; Ascher, P; Gerbaux, M; Giovinazzo, J; Grevy, S; Nieto, T Kurtukian; Magron, C; Agramunt, J; Algora, A; Guadilla, V; Montaner-Piza, A; Morales, A I; Orrigo, S E A; Rubio, B; Ahn, D S; Doornenbal, P; Fukuda, N; Inabe, N; Kiss, G; Kubo, T; Kubono, S; Nishimura, S; Phong, V H; Sakurai, H; Shimizu, Y; Soderstrom, P -A; Sumikama, T; Suzuki, H; Takeda, H; Wu, J; Fujita, Y; Tanaka, M; Gelletly, W; Aguilera, P; Molina, F; Diel, F; Lubos, D; de Angelis, G; Napoli, D; Borcea, C; Boso, A; Cakirli, R B; Ganioglu, E; Chiba, J; Nishimura, D; Oikawa, H; Takei, Y; Yagi, S; Wimmer, K; de France, G; Go, S

    2016-01-01

    In an experiment with the BigRIPS separator at the RIKEN Nishina Center, the fragmentation of a $^{78}$Kr beam allowed the observation of new neutron-deficient isotopes at the proton drip-line. Clean identification spectra could be produced and $^{63}$Se, $^{67}$Kr, and $^{68}$Kr were identified for the first time. In addition, $^{59}$Ge was also observed. Three of these isotopes, $^{59}$Ge, $^{63}$Se, and $^{67}$Kr, are potential candidates for ground-state two-proton radioactivity. In addition, the isotopes $^{58}$Ge, $^{62}$Se, and $^{66}$Kr were also sought but without success. The present experiment also allowed the determination of production cross sections for some of the most exotic isotopes. These measurements confirm the trend already observed that the empirical parameterization of fragmentation cross sections, EPAX, significantly overestimates experimental cross sections in this mass region.

  14. Carbon cluster diagnostics-I: Direct Recoil Spectroscopy (DRS) of Ar+ and Kr+ bombarded graphite

    CERN Document Server

    Ahmad, Shoaib; Qayyum, A; Ahmad, B; Bahar, K; Arshed, W

    2016-01-01

    Measurements of the energy spectra of multiply charged positive and negative carbon ions recoiling from graphite surface under 100 and 150 keV argon and krypton ion bombardment are presented. With the energy spectrometer set at recoil angle of 79.5 degrees, direct recoil (DR) peaks have been observed with singly as well as multiply charged carbon ions , where n = 1 to 6. These monatomic and cluster ions have been observed recoiling with the characteristic recoil energy E(DR) . We have observed sharp DR peaks. A collimated projectile beam with small divergence is supplemented with a similar collimation before the energy analyzer to reduce the background of sputtered ions due to scattered projectiles.

  15. Analysis results of PAVE sampling of groundwaters from open boreholes OL-KR2, OL-KR7, OL-KR13 and OL-KR15 at Olkiluoto, Eurajoki, in 2004

    Energy Technology Data Exchange (ETDEWEB)

    Hirvonen, H. [Teollisuuden Voima Oyj, Eurajoki (Finland); Hatanpaa, E. [lnsinoeoeritoimisto Paavo Ristola Oy, Hollola (Finland)

    2005-12-15

    Four groundwater samples were collected at Olkiluoto from open boreholes OL-KR2, OL-KR7, OL-KR13 and OL-KR15 with pressurised water sampling equipment (PAVE) between summer 2004 and the beginning of 2005. The aim of the ground water sampling was to get information for the basis of the monitoring program during ONKALO construction. Sampling sections were mainly chosen so that the results of the chemical analyses from earlier studies could be used for comparison. This study is a part of Olkiluoto's monitoring programme (OMO). This study presents the sampling methods and the results of the laboratory analyses of groundwater samples from the open boreholes OL-KR2/328.5-330.5 m, OL-KR7/275.5- 289.5 m, OL-KR13/362-365 m and OL-KR15/241-245 m. The analytical results of the groundwater samplings are compared to earlier analytical results. According to Davis and De Wiest's ( 1967) classification, all ground water samples represent the borehole water type Na-Cl. All ground water samples were brackish ( 1000 mg/L < TDS < 1 0000 mg/L) according to Davis's ( 1964) TDS classification. Comparison of analytical results of the samples to earlier results shows that some changes have occurred between samplings. Other parameters, with couple of particular exceptions, have a downward trend, but bicarbonate concentration has increased in all boreholes. Concentrations of main parameters have changed most in OL-KR7 and OL-KR13 waters. Gas analyses results have not changed significantly, but increased carbon dioxide concentration is noticed in gas analysis results also. (orig.)

  16. The Electra KrF laser system

    Energy Technology Data Exchange (ETDEWEB)

    Hegeler, F; Friedman, M; Albert, T; Parish, J [Commonwealth Technology, Inc., Alexandria, VA 22315 (United States); Myers, M C; Wolford, M F; Sethian, J D; Giuliani, J L [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States); Burns, P [Research Support Instruments, Lanham, MD 20706 (United States); Jaynes, R [Science Applications International, Corp., McLean, VA 22102 (United States)], E-mail: frank.hegeler@nrl.navy.mil

    2008-05-15

    This paper presents a brief overview of the Electra laser system and reports on the most recent results. The laser system consists of an electron beam pumped main amplifier with an aperture of 30 cm x 30 cm, an e-beam pumped 10 cm x 10 cm pre-amplifier, and a KrF discharge laser serving as the seed oscillator. The electron beam amplifiers are pumped from both sides. Full laser system shots have been completed with a laser energy of 450 J. The main amplifier, operating as an oscillator, has demonstrated 25,000 continuous laser shots at 2.5 Hz single sided pumping as well as 16,600 shots at 2.5 Hz at {approx}300 J/shot within 2 hours.

  17. High-spin states in 75Kr

    Science.gov (United States)

    Chishti, A. A.; Gelletly, W.; Lister, C. J.; Mcneill, J. H.; Varley, B. J.; Love, D. J. G.; Skeppstedt, O.

    1989-09-01

    Levels in the 75Kr nucleus were populated in the inverse 24Mg( 54Fe, 2pn) 75Kr reaction at beam energies of 177 and 190 MeV. In the reaction study at 177 MeV, the γ-rays were detected in coincidence with neutrons and mass-75 nuclei and in the reaction at 190 MeV only γγ-coincidence data were collected. Using the γγ-neutron gated γγ- and Recoil-γγ-coincidence techniques, we were able to develop the level scheme up to spins ( {37+}/{2}) and ( {31-}/{2}) in the positive- and negative-parity bands, respectively. These spins are high enough to allow us to study alignment effects in this mass region. The signature splitting at low spin can be reproduced in a cranked shell model calculation assuming a quadrupole deformation β2 = 0.37 and a slightly triaxial ( γ≈ -10°) shape for positive-parity states but an axial shape for the negative-parity sequence. The spin alignment as a function of rotational frequency has been studied; in the positive-parity band alignment is observed at a rotational frequency of h̵ω ≈ 0.63 MeV and in the negative-parity band the alignment occurs at h̵ω ≈ 0.57 MeV. The observed alignment in both bands is associated with a pair of g{9}/{2} protons, and the difference in the alignment frequencies is thought to be due to differing intrinsic shapes.

  18. Determination of the separation efficiencies of a single-stage cryogenic distillation setup to remove krypton out of xenon by using a (83m)Kr tracer method.

    Science.gov (United States)

    Rosendahl, S; Brown, E; Cristescu, I; Fieguth, A; Huhmann, C; Lebeda, O; Murra, M; Weinheimer, C

    2015-11-01

    The separation of krypton and xenon is of particular importance for the field of direct dark matter search with liquid xenon detectors. The intrinsic contamination of the xenon with radioactive (85)Kr makes a significant background for these kinds of low count-rate experiments and has to be removed beforehand. This can be achieved by cryogenic distillation, a technique widely used in industry, using the different vapor pressures of krypton and xenon. In this paper, we present an investigation on the separation performance of a single stage distillation system using a radioactive (83m)Kr-tracer method. The separation characteristics under different operation conditions are determined for very low concentrations of krypton in xenon at the level of (83m)Kr/Xe = 1.9 ⋅ 10(-15), demonstrating, that cryogenic distillation in this regime is working. The observed separation is in agreement with the expectation from the different volatilities of krypton and xenon. This cryogenic distillation station is the first step on the way to a multi-stage cryogenic distillation column for the next generation of direct dark matter experiment XENON1T.

  19. Ars Himera / Irina Lobanova

    Index Scriptorium Estoniae

    Lobanova, Irina

    2003-01-01

    Iseloomustatakse praegust aega ja moodsat kunsti: valitseb vastutustundetus ja ebainimlikkus. Näited - professor von Hageni "Korpwelten" ja uusim kunstinähtus Ars Chimaera - eksponeerimise eesmärgil surrogaatsete elusolendite saamise kunst

  20. Discharge and radiation characteristics of Xe one-barrier excilamps

    Science.gov (United States)

    Arnold, Erich; Lomaev, Mikhail I.; Shitz, Dmitrii V.; Skakun, Victor S.; Tarasenko, Victor F.

    2002-03-01

    The paper is devoted to experimental study of discharge and radiation characteristics taking place in Xe one-barrier excilamps at broad variations of excitation pulse parameters and gas fill-pressures. The B-X band of the molecule Xe2* dominates the lamp spectrum and has high efficiency. Radiation of monatomic lines and luminescence of the lamp bulb can be observed too. The molecule Xe2* band B-X radiation of luminescence time dependence and luminescence of the lamp bulb quartz are similar, at the same time the radiation of Xe monatomic line (lambda) equals 467 nm has obviously some other form. Depending on excitation conditions, i.e. power, duration and excitation impulse form, a gas discharge Xe excilamp, different by homogeneity level and radiation efficiency types of discharge can be realized. Formation of discharge homogeneity is the necessary condition to obtain high efficiencies of excimer radiation in this type of lamp. In one-barrier xenon excilamps with internal small curvature of an electrode, a homogeneous discharge forms at pressures up to 300 Torr.

  1. Driving photochemistry by clustering: the ICl-Xe case.

    Science.gov (United States)

    Glodic, Pavle; Kartakoullis, Andreas; Fárník, Michal; Samartzis, Peter C; Kitsopoulos, Theofanis N

    2012-10-21

    We present slice imaging data demonstrating the influence of clustering on the photodissociation dynamics of a diatomic molecule: iodine monochloride (ICl) was dissociated at 235 nm in He and Xe seed gasses, probing both Cl and I photofragment energy and angular distributions. We observe that the kinetic energy releases of both Cl and I fragments change from He to Xe seeding. For Cl fragments, the seeding in Xe increases the kinetic energy release of some Cl fragments with a narrow kinetic energy distribution, and leads to some fragments with rather broad statistical distribution falling off exponentially from near-zero energies up to about 2.5 eV. Iodine fragment distribution changes even more dramatically from He to Xe seeding: sharp features essentially disappear and a broad distribution arises reaching to about 2.5 eV. Both these observations are rationalized by a simple qualitative cluster model assuming ICl dissociation inside larger xenon clusters and "on surface" of smaller Xe species.

  2. The Slitless Spectroscopy Data Extraction Software aXe

    CERN Document Server

    Kümmel, Martin; Pirzkal, Norbert; Kuntschner, Harald; Pasquali, Anna

    2008-01-01

    The methods and techniques for the slitless spectroscopy software aXe, which was designed to reduce data from the various slitless spectroscopy modes of Hubble Space Telescope instruments, are described. aXe can treat slitless spectra from different instruments such as ACS, NICMOS and WFC3 through the use of a configuration file which contains all the instrument dependent parameters. The basis of the spectral extraction within aXe are the position, morphology and photometry of the objects on a companion direct image. Several aspects of slitless spectroscopy, such as the overlap of spectra, an extraction dependent on object shape and the provision of flat-field cubes, motivate a dedicated software package, and the solutions offered within aXe are discussed in detail. The effect of the mutual contamination of spectra can be quantitatively assessed in aXe, using spectral and morphological information from the companion direct image(s). A new method named 'aXedrizzle' for 2D rebinning and co-adding spectral data,...

  3. Origin of anomalous Xe-H in nanodiamond stardust

    Energy Technology Data Exchange (ETDEWEB)

    Kratz, K. L. [Max-Planck-Institut für Chemie, Otto-Hahn-Institut, D-55128 Mainz, Germany and Fachbereich Chemie, Pharmazie und Geowissenschaften, Universitat Mainz, Mainz (United States); Farouqi, K. [Max-Planck-Institut für Chemie, Otto-Hahn-Institut, D-55128 Mainz, Germany and Zentrum für Astronomie der Universität Heidelberg, D-69120 Heidelberg (Germany); Hallmann, O. [Max-Planck-Institut für Chemie, Otto-Hahn-Institut, D-55128 Mainz (Germany); Pfeiffer, B. [II. Physikalisches Institut, Univ. Giessen, D-35392 Giessen (Germany); Ott, U. [Max-Planck-Institut für Chemie, Otto-Hahn-Institut, D-55128 Mainz (Germany); Univ. of West Hungary, H-9700 Szombathely (Hungary)

    2014-05-09

    Still today, the nucleosynthesis origin of Xe-H in presolar nanodiamonds is far from understood. Historically possible explanations were proposed by a secondary “neutron-burst” process occurring in the He- or C/O-shells of a type-II supernova (SN-II), which are, however, not fully convincing in terms of modern nucleosynthesis conditions. Therefore, we have investigated Xe isotopic abundance features that may be diagnostic for different versions of a classical, primary r-process in high-entropy-wind (HEW) ejecta of core-collapse SN-II. We report here on parameter tests for non-standard r-process variants, by varying electron abundances (Y{sub e}), ranges of entropies (S) and expansion velocities (V{sub exp}) with their correlated neutron-freezeout times (τ(freeze)) and temperatures (T{sub 9}(freeze)). From this study, we conclude that a best fi to the measured Xe-H abundance ratios {sup i}Xe/{sup 136}Xe can be obtained with the high-S “main” component of a “cold” r-process variant.

  4. Origin of Anomalous Xe-H in Nanodiamond Stardust

    CERN Document Server

    Kratz, K -L; Hallmann, O; Pfeiffer, B; Ott, U

    2014-01-01

    Still today, the nucleosynthesis origin of Xe-H in presolar nanodiamonds is far from understood. Historically, possible explanations were proposed by a secondary "neutron-burst" process occurring in the He- or C/O-shells of a type-II supernova (SN-II), which are, however, not fully convincing in terms of modern nucleosynthesis conditions. Therefore, we have investigated Xe isotopic abundance features that may be diagnostic for different versions of a classical, primary r-process in high-entropy-wind (HEW) ejecta of core-collapse SN-II. We report here on parameter tests for non-standard r-process variants, by varying electron abundances (Y$_e$), ranges of entropies (S) and expansion velocities (V$_{exp}$) with their correlated neutron-freezeout times ($\\tau$(freeze)) and temperatures (T$_9$(freeze)). From this study, we conclude that a best fit to the measured Xe-H abundance ratios $^i$Xe/$^{136}$Xe can be obtained with the high-S "main" component of a "cold" r-process variant.

  5. The I-Pu-Xe age of the Moon

    Science.gov (United States)

    Swindle, T. D.; Caffee, M. W.; Hohenberg, C. M.

    1984-01-01

    The Rb-Sr analyses of some lunar samples which indicate that the Moon is close to the age of primitive meteorites are only reliable to within about 100 m.y. A potentially more precise chronometer is the I-Pu-Xe system. I129 has a 17 m.y. halflife and decays to Xe129; Pu244, with an 82 m.y. halflife, produces Xe131 to Xe136 in fission. The I129/Pu244 ratio has a halflife of 21 m.y. Xenon retention for the Earth could have begun as late as the event that gave birth to the Moon. For the Moon, it is hard to imagine that xenon retention could have begun before re-accretion of the fissioned (and initially dispersed?) material, particularly if that material got hot enough to account for the depletion of the volatile elements. Thus, if fission model are correct, xenon retention in the Earth certainly began no later than in the Moon, and possibly began earlier. Therefore, the I-Pu-Xe system is only marginally consistent with a fission origin. If further study confirms that the I/U ratio of the Moon is .01 or less, or if gas-rich lunar highland breccias with higher ratios of I129 to Pu244 are found, it would be difficult to explain the results in an earth-fission model of lunar origin.

  6. Krüppel homolog 1 (Kr-h1) mediates juvenile hormone action during metamorphosis of Drosophila melanogaster.

    Science.gov (United States)

    Minakuchi, Chieka; Zhou, Xiaofeng; Riddiford, Lynn M

    2008-01-01

    Juvenile hormone (JH) given at pupariation inhibits bristle formation and causes pupal cuticle formation in the abdomen of Drosophila melanogaster due to its prolongation of expression of the transcription factor Broad (BR). In a microarray analysis of JH-induced gene expression in abdominal integument, we found that Krüppel homolog 1 (Kr-h1) was up-regulated during most of adult development. Quantitative real-time PCR analyses showed that Kr-h1 up-regulation began at 10h after puparium formation (APF), and Kr-h1 up-regulation occurred in imaginal epidermal cells, persisting larval muscles, and larval oenocytes. Ectopic expression of Kr-h1 in abdominal epidermis using T155-Gal4 to drive UAS-Kr-h1 resulted in missing or short bristles in the dorsal midline. This phenotype was similar to that seen after a low dose of JH or after misexpression of br between 21 and 30 h APF. Ectopic expression of Kr-h1 prolonged the expression of BR protein in the pleura and the dorsal tergite. No Kr-h1 was seen after misexpression of br. Thus, Kr-h1 mediates some of the JH signaling in the adult abdominal epidermis and is upstream of br in this pathway. We also show for the first time that the JH-mediated maintenance of br expression in this epidermis is patterned and that JH delays the fusion of the imaginal cells and the disappearance of Dpp in the dorsal midline.

  7. Level structures of neutron-rich Xe isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, I.; Lister, C.J.; Morss, L.R. [and others

    1995-08-01

    The level structures of neutron-rich Xe isotopes were determined by observing prompt gamma-ray coincidences in {sup 248}Cm fission fragments. A 5-mg {sup 248}Cm, in the form of {sup 248}Cm-KCl pellet, was placed inside Eurogam array which consisted of 45 Compton-suppressed Ge detectors and 5 Low-Energy Photon Spectrometers. Transitions in Xe isotopes were identified by the appearance of new peaks in the {gamma}-ray spectra obtained by gating on the gamma peaks of the complementary Mo fragments.

  8. Lifetime measurement of high spin states in {sup 75}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Trivedi, T. [Department of Physics, University of Allahabad, Allahabad-211001 (India); Palit, R. [Tata Institute of Fundamental Research, Mumbai-400005 (India); Negi, D. [Inter University Accelerator Centre, New Delhi-110067 (India); Naik, Z. [Tata Institute of Fundamental Research, Mumbai-400005 (India); Yang, Y.-C. [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); Sun, Y. [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States); Sheikh, J.A. [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States); Physics Division, Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831 (United States); Department of Physics, University of Kashmir, Srinagar 190 006 (India); Dhal, A. [Department of Physics, Banaras Hindu University, Varanasi 221005 (India); Raju, M.K. [Department of Nuclear Physics, Andhra University, Visakhapatnam-530003 (India); Appannababu, S. [Department of Physics, MS University of Baroda, Vadodara-390002 (India); Kumar, S. [Department of Physics and Astrophysics, University of Delhi, Delhi-110007 (India); Choudhury, D. [Department of Physics, IIT Roorkee, Roorkee-247667 (India); Maurya, K. [Department of Physics, University of Allahabad, Allahabad-211001 (India); Mahanto, G.; Kumar, R.; Singh, R.P.; Muralithar, S. [Inter University Accelerator Centre, New Delhi-110067 (India); Jain, A.K. [Department of Physics, IIT Roorkee, Roorkee-247667 (India); Jain, H.C. [Tata Institute of Fundamental Research, Mumbai-400005 (India); Pancholi, S.C. [Inter University Accelerator Centre, New Delhi-110067 (India)

    2010-03-01

    The lifetimes of high spin states of {sup 75}Kr have been determined via {sup 50}Cr ({sup 28}Si, 2pn) {sup 75}Kr reaction in positive parity band using the Doppler-shift attenuation method. The transition quadrupole moments Q{sub t} deduced from lifetime measurements have been compared with {sup 75}Br. Experimental results obtained from lifetime measurement are interpreted in the framework of projected shell model.

  9. The Smallest Degree Sum That Yields Potentially Kr+1 - K3-Graphic Sequences

    Institute of Scientific and Technical Information of China (English)

    Meng-xiao Yin

    2006-01-01

    Let σ(Kr+1 - K3, n) be the smallest even integer such that each n-term graphic sequence π =Kr+1 - K3 as a subgraph, where Kr+1 - K3 is a graph obtained from a complete graph Kr+1 by deleting three edges which form a triangle. In this paper, we determine the value σ(Kr+1 -- K3,n) for r ≥ 3 and n ≥ 3r + 5.

  10. Impacts of Xe-135m on Xenon Reactivity in Thermal Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jaeha; Kim, Yonghee [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2013-05-15

    To our best knowledge, the effect of the omission of Xe-135m has never been evaluated before. Recently, we found that the cross section data of Xe-135m are available from the TENDL-2011 library based on the theoretical evaluations. According to the TENDL data, the neutron absorption cross section of Xe-135m turns out to be much larger than that of Xe-135 in the thermal neutron region, as shown in Fig. 1. In this paper, we evaluated the impacts of Xe-135m on the total steady-state and transient Xe reactivity. By taking into account Xe-135m in the I-135 decay, we have found the followings. First, the steady state total xenon reactivity is slightly increased by ∼0.94% as compared with the conventional model. Second, the impact of Xe-135m on the transient Xe reactivity is rather significant. In particular, the reactivity change during the early transient period can be noticeably enhanced by accounting for Xe-135. And this indicates that Xe-135m may play an important role in measuring the PCR for which the transient Xenon reactivity should be accurately estimated. Currently, the impacts of Xe-135 on the PCR measurement are under investigation.

  11. Geophysical drillhole logging and imaging of drillholes OL-KR54, OL-KR55 and OL-KR55B at Olkiluoto in 2010 and 2011

    Energy Technology Data Exchange (ETDEWEB)

    Tarvainen, A.-M. (Suomen Malmi Oy, Espoo (Finland)); Heikkinen, E. (Poeyry Finland Oy, Vantaa (Finland))

    2011-08-15

    Suomen Malmi Oy conducted geophysical drillhole logging as well as optical and acoustic imaging of the drillholes OL-KR54, OL-KR55 and OL-KR55B at the Olkiluoto site in Eurajoki between August 2010 and January 2011. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and data processing. The report describes field operation, equipment as well as processing procedures and shows the obtained results and an analysis of their quality in the appendices. New focused resistivity, susceptibility, natural gamma and density probes were tested and compared with old probes. This report describes the major features of new probes and the comparison with old probes. The raw and processed data are delivered digitally in WellCAD, PDF and Excel format. (orig.)

  12. Hydraulic conductivity measurements with HTU at Eurajoki, Olkiluoto, drillholes OL-KR19, OL-KR45 and OL-KR46 in 2009 and 2010

    Energy Technology Data Exchange (ETDEWEB)

    Haemaelaeinen, H. [Geopros Oy, Helsinki (Finland)

    2011-10-15

    As a part of the site investigations for the disposal of spent nuclear fuel, hydraulic conductivity measurements were carried out with HTU-equipment in drillholes OL-KR19, OL-KR45 and OL-KR46 at Eurajoki, Olkiluoto. The objective was to investigate the distribution of the hydraulic conductivity in the surrounding bedrock volume. Measurements were carried out during 2009 and 2010. The total length of the borehole OL-KR19 is 544,34 m, 241,80 m of which was covered by 121 standard tests with 2 m packer separation as specified in the measurement plan. Respectively, OL-KR45 is 1023,30 m long and 63 similar tests were made in it covering 126,00 m of the hole and OL-KR46 600,10 m long, 151 tests made covering 301,35 m. The measured sections are around the depths of the planned repository. Double-packer constant-head method was used throughout with nominal 200 kPa overpressure. Injection stage lasted normally 20 minutes and fall-off stage 10 minutes. The tests were often shortened if there were clear indications that the hydraulic conductivity is below the measuring range of the system. The pressure in the test section was let to stabilise at least 5 min before injection. In some test sections the test stage times were extended. Two transient (Horner and 1/Q) interpretations and one stationary- state (Moye) interpretation were made in-situ immediately after the test. The Hydraulic Testing Unit (HTU-system) is owned by Posiva Oy and it was operated by Geopros Oy. (orig.)

  13. Nuclear-induced XeBr/asterisk/ photolytic laser model

    Science.gov (United States)

    Wilson, J. W.

    1980-01-01

    Parameters for a photolytically pumped alkyl iodide lasant gas by the nuclear-induced XeBr excimer fluorescence are calculated according to a detailed kinetic model. High gain on the atomic iodine 2P1/2 state is estimated and 100-mJ pulses with an average power output on the order of 1 kW appear possible.

  14. Collective states of even Xe isotopes in IBM+MQRPA

    Directory of Open Access Journals (Sweden)

    Efimov A. D.

    2016-01-01

    Full Text Available A modification of the Quasiparticle Random Phase Approximation (QRPA with small ground state correlations is suggested. The lowest energy phonon is used as the image of d-boson of the Interacting Boson Model 1 (IBM1 and applied to microscopical calculations of the IBM1 parameters. Results are compared with experimental data for Xe isotopes.

  15. Generator Coordinate Method Analysis of Xe and Ba Isotopes

    Science.gov (United States)

    Higashiyama, Koji; Yoshinaga, Naotaka; Teruya, Eri

    Nuclear structure of Xe and Ba isotopes is studied in terms of the quantum-number projected generator coordinate method (GCM). The GCM reproduces well the energy levels of high-spin states as well as low-lying states. The structure of the low-lying states is analyzed through the GCM wave functions.

  16. Imaging Thomson scattering measurements of radiatively heated Xe

    Energy Technology Data Exchange (ETDEWEB)

    Pollock, B; Meinecke, J; Kuschel, S; Ross, J S; Divol, L; Glenzer, S H; Tynan, G R

    2012-05-01

    Uniform density and temperature Xe plasmas have been produced over >4 mm scale-lengths using x-rays generated in a cylindrical Pb cavity. The cavity is 750 {micro}m in depth and diameter, and is heated by a 300 J, 2 ns square, 1054 nm laser pulse focused to a spot size of 200 {micro}m at the cavity entrance. The plasma is characterized by simultaneous imaging Thomson scattering measurements from both the electron and ion scattering features. The electron feature measurement determines the spatial electron density and temperature profile, and using these parameters as constraints in the ion feature analysis allows an accurate determination of the charge state of the Xe ions. The Thomson scattering probe beam is 40 J, 200 ps, and 527 nm, and is focused to a 100 {micro}m spot size at the entrance of the Pb cavity. Each system has a spatial resolution of 25 {micro}m, a temporal resolution of 200 ps (as determined by the probe duration), and a spectral resolution of 2 nm for the electron feature system and 0.025 nm for the ion feature system. The experiment is performed in a Xe filled target chamber at a neutral pressure of 3-10 Torr, and the x-rays produced in the Pb ionize and heat the Xe to a charge state of 20 {+-} 4 at up to 200 eV electron temperatures.

  17. Assessment of right ventricular ejection fraction during intravenous /sup 133/Xe pulmonary ventilation study

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S.M.; Spencer, R.P.; Herrera, N.E.

    1985-01-01

    Intravenous /sup 133/Xe in saline was used to estimate right-ventricular ejection fraction (RVEF). In three healthy volunteers, the first pass RVEF with /sup 133/Xe was followed by RVEF estimation by intravenous /sup 99m/Tc-pertechnetate. There was agreement between the /sup 133/Xe and 99mTc determined values. Subjects rebreathed the liberated /sup 133/Xe gas, allowing an estimation of regional pulmonary ventilation. Intravenous /sup 133/Xe in saline may have potential use in measuring RVEF, as well as in evaluating pulmonary function in cor pulmonale.

  18. Observation of hyperfine mixing in measurements of a magnetic octupole decay in isotopically pure nickel-like 129Xe and 132Xe ions

    Energy Technology Data Exchange (ETDEWEB)

    Trabert, E; Beiersdorfer, P; Brown, G V

    2006-12-21

    We present measurements of high statistical significance of the rate of the magnetic octupole (M3) decay in nickel-like ions of isotopically pure {sup 129}Xe and {sup 132}Xe. On {sup 132}Xe, an isotope with zero nuclear spin and therefore without hyperfine structure, the lifetime of the metastable level was established as (15.06 {+-} 0.24) ms. On {sup 129}Xe, an additional fast (2.7 {+-} 0.1 ms) decay component was established that represents hyperfine mixing with a level that decays by electric quadrupole (E2) radiation.

  19. Knowing the good from the bad: does being aware of KR content matter?

    Science.gov (United States)

    Patterson, Jae T; Azizieh, Jana

    2012-12-01

    Previous researchers have suggested that providing KR based on only successful (i.e., good trials) trials enhances learning compared to providing KR on unsuccessful trials (i.e., poor trials). However, the learners were unaware the content of their KR display was based entirely on their successful or unsuccessful trials. Thus, the purpose of the present experiment was to determine whether learning after providing KR after relatively good trials would persist if participants were aware of their KR content. All participants propelled a slider with their non-dominant hand to a pre-determined distance on a linear slide. Participant's vision was occluded before, during and after their motor action. Similar to previous research, all participants were provided KR on three trials in a series of 6 trial blocks regarding their three best (KR good) or three worst (KR poor) trials in the block, and were either aware (good-aware; poor-aware) or unaware (good-unaware, poor-unaware) of content in their KR display. The retention results showed the groups aware of their KR content demonstrated superior learning to the groups unaware of their KR content. These findings suggest that in addition to the motivational components of KR, awareness of the KR content directly impacted motor skill acquisition not whether KR was presented on good trials or poor trials.

  20. Angļu valodas vārdu krājuma apguve, spēlējot datorspēles

    OpenAIRE

    Ločmele, Līga

    2013-01-01

    Angļu valodas vārdu krājuma apguve, spēlējot datorspēles, nav pilnībā izpētīta, taču datorspēles nenoliedzami piedāvā iespēju spēlējot apgūt jaunus vārdus. Šī pētnieciskā darba mērķis ir noteikt vai un kādā mērā noris vārdu krājuma apguve un noskaidrot kādas vārdu krājuma apguves stratēģijas tiek pielietotas spēlējot dzīves simulācijas datorspēli „Sims 3”. Šim nolūkam tika izmantots vārdu krājuma pārbaudes darbs un domu protokola analīze, kā arī datorprogramma, kas nosaka vārdu vispārējās sas...

  1. Ramon Llull's Ars Magna

    DEFF Research Database (Denmark)

    Jensen, Thessa

    of the Christian faith. He soon discovered that the main challenge was to explain the divine Trinity to non Christians. Furthermore, he realised that culture and language barriers must be taken into account when he tried to explain the Christian faith. In-stead of focussing on the differences, Llull sought out...... might be a viable and valuable approach to understand some of the challenges and possibilities found in computer science and ethics. Vita Llull was born in 1232 in Palma de Mallorca, a melting pot for different cul-tures and religions at the time. Being educated at the king’s court, Llull learned......Ramon Llull’s Ars Magna Thessa Jensen Institute for Communication and Psychology, Aalborg University Aalborg, Denmark thessa@hum.aau.dk The Great Art of Ramon Llull — the Ars Magna — must be seen as one of the basic philosophical approaches to formalisation of thought, language, and knowledge...

  2. Combined K-Ar and 40Ar/39Ar dating of the upper Jaramillo reversal

    Science.gov (United States)

    Guillou, Herve; Carracedo, Juan Carlos; Kissel, Catherine; Laj, Carlo; Nomade, Sebastien; Perez Torrado, Francisco Jose; Rodriguez Gonzalez, Alejandro; Wandres, Camille

    2013-04-01

    The Jaramillo subchron was first evidenced in 1966 (Doell and Dalrymple) through the Rhyolotic domes of the Valles Caldera, New Mexico (USA). 40Ar/39Ar studies achieved by Spell et McDougall (1992), Spell et Harrison (1993), Izett and Obradovich (1994) and Singer et al. (1994) defined the base of this subchron at 1053±6 ka, and the ceiling at 986±5 ka. Channell et al. (2009) delimited the age of the Jaramillo subchron by astronomic calibration (base 1071 ka, top 990 ka). To provide additional absolute ages on this geomagnetic period, which is critical to improve our knowledge of the earth magnetic field behaviour, we have carried out a study combining paleomagnetism and isotopic dating of a lava sequence from Tenerife island. This sequence of basaltic lava flows is some 500 m thick. The first 400 m present, based on field magnetometer measurements, normal polarity lavas, with dykes of normal and reverse polarity, passing at the top to reverse polarity lavas. Preliminary K-Ar ages bracketed this sequence between 1018 ± 18 ka and 978 ± 17 ka. Therefore, the upper Jaramillo reversal at least appeared to be potentially recorded in this sequence. A more detailed paleomagnetic study was then carried out to more precisely delimit the reversal itself (see Laj et al., session EMRP3.4). We have undertaken 40Ar/39Ar incremental heating and unspiked K-Ar experiments on groundmass from four transitionally magnetized flows. The first transitional flow is K-Ar dated at 993 ± 18 ka and 40Ar/39Ar dated at 991 ± 13 ka, the second at 981 ± 17 ka (K-Ar) and 1000 ± 13 ka (40Ar/39Ar), the third at 950 ± 17 ka (K-Ar) and 1000 ± 8 ka (40Ar/39Ar) and the fourth at 984 ± 17 ka (K-Ar) and 977 ± 12 (40Ar/39Ar). 40Ar/39Ar ages and K-Ar ages (relative to FCT 28.02 Ma) are indistinguishable at 2σ. The age of the upper boundary of the Jaramillo event calculated combining 40Ar/39Ar ages and K-Ar ages is 992 ± 6 ka, in agreement with previous estimates.

  3. Photoionization of Ar VIII

    Science.gov (United States)

    Liang, Liang; Jiang, Wen-xian; Zhou, Chao

    2017-01-01

    The photoionization cross section, energy levels and widths of 22 Rydberg series (in the autoionization region) for Na-like Ar VIII were investigated by using of R-matrix method. The relativistic distorted-wave method is used to calculate the radial functions, and QB method of Quigly-Berrington [Quigley et al. 1998] is employed to calculate the resonance levels and widths. We have identified the formant in the figure of the photoionization cross section.

  4. Ars Electronica tulekul / Rael Artel

    Index Scriptorium Estoniae

    Artel, Rael, 1980-

    2003-01-01

    6.-11. IX toimub Austrias Linzis "Ars Electronica" festival, mille teema on "Code - The Language of Our Time". Festivali kavast, osalejatest, ava-performance'ist "Europe - A Symphonic Vision", näitusest "Cyberarts 2003. Prix Ars Electronica"

  5. Cross-Section Measurements of the 86Kr(g,n) Reaction to Probe the s-Process Branching at 85Kr

    CERN Document Server

    Raut, R; Rusev, G; Tornow, W; Iliadis, C; Lugaro, M; Buntain, J; Goriely, S; Kelley, J H; Schwengner, R; Banu, A; Tsoneva, N

    2013-01-01

    We have carried out photodisintegration cross-section measurements on 86Kr using monoenergetic photon beams ranging from the neutron separation energy, S_n = 9.86 MeV, to 13 MeV. We combine our experimental 86Kr(g,n)85Kr cross section with results from our recent 86Kr(g,g') measurement below the neutron separation energy to obtain the complete nuclear dipole response of 86Kr. The new experimental information is used to predict the neutron capture cross section of 85Kr, an important branching point nucleus on the abundance flow path during s-process nucleosynthesis. Our new and more precise 85Kr(n,g)86Kr cross section allows to produce more precise predictions of the 86Kr abundance from s-process models. In particular, we find that the models of the s-process in asymptotic giant branch stars of mass < 1.5 Msun, where the 13C neutron source burns convectively rather than radiatively, represent a possible solution for the highest 86Kr/82Kr ratios observed in meteoritic stardust SiC grains.

  6. ARABIC LIGHT STEMMER (ARS

    Directory of Open Access Journals (Sweden)

    ASMA AL-OMARI

    2014-12-01

    Full Text Available Stemming is a main step used to process textual data. It is usually used in several types of applications such as: text mining, information retrieval (IR, and natural language processing (NLP. A major task in stemming is to standardize words; which can be achieved by reducing each word to its base (root or stem. Arabic stemming is not an easy task. Unlike other languages, Arabic language is a highly inflected language, since it uses many inflectional forms. Researchers are divided on the benefit of using stemming in fields of IR, NLP...etc., since in Arabic the morphological variants of a certain word are not always semantically related. The aim of this paper is to design and implement a new Arabic light stemmer (ARS which is not based on Arabic root patterns. Instead, it depends on well defined mathematical rules and several relations between letters. A series of tests were conducted on ARS stemmer to compare its effectiveness with the effectiveness of two other Arabic stemmers. Test shows clearly the effectiveness superiority of ARS compared to effectiveness of these two Arabic stemmers.

  7. Mistika u životu kršćana

    OpenAIRE

    Špehar, Milan

    2004-01-01

    Sve veći interes za mistiku na raznim područjima ljudskoga istraživanja traži i od nas kršćana i naših teologija određene prosudbe i istraživanja. Događa se da govorimo o istim stvarima, samo jezikom današnjega vremena. U biti ostaje za sve isto iskustvo, a to je da je mistika doista iskustvo Neiskustvenoga. Ona živi unutar kršćanstva i izvan njega, bila prihvaćana ili odbacivana. Kršćanska mistika ima svoje temeljne izvore u Sv. pismu, liturgiji i Crkvi. U tom ambijentu ona stvara svoje pojm...

  8. Dynamic moments of inertia in Xe, Cs and Ba nuclei

    Energy Technology Data Exchange (ETDEWEB)

    El-Samman, H.; Barci, V.; Gizon, A.; Gizon, J.; Hildingsson, L.; Jerrestam, D.; Klamra, W.; Kossakowski, R.; Lindblad, T.; Gono, Y.; Bengtsson, T.; Leander, G.A.

    1984-01-01

    The ..gamma..-rays following the reactions induced by /sup 12/C ions on /sup 115/In, /sup 112/,/sup 117/,/sup 122/Sn and /sup 123/Sb targets have been investigated using six NaI(Tl) detectors in a two-dimensional arrangement. The collective moment of inertia I(/sup 2/) /sub band/ of /sup 118/,/sup 122/Xe, /sup 123/Cs and /sup 128/,/sup 130/Ba have been extracted from the energy-correlation spectra. The behaviour of these nuclei and the observed differences are interpreted in terms of high-spin collective properties. Data are also presented on the effective moment of inertia I(/sup 2/)/sub eff/ of /sup 118/Xe and /sup 130/Ba measured by sum-spectrometer techniques. 13 references.

  9. Examining the Preferred Self-Controlled KR Schedules of Learners and Peers During Motor Skill Learning.

    Science.gov (United States)

    McRae, Matthew; Patterson, Jae Todd; Hansen, Steve

    2015-01-01

    In many practical situations, learners are provided with feedback in the form of knowledge of results (KR) by a peer. However, when peers provide KR is currently unknown. When given the opportunity to request KR in a self-controlled manner, some participants have reported a preference for requesting KR after good performances. Alternatively, peers may provide KR in a different fashion. Subsequently, a discrepancy between the learner's desire to receive KR and when a peer provides KR may arise. In our study, peer- and self-controlled KR schedules were compared. Participants were peers who controlled KR (PC; 8), learners with peers (P-L; 8), or learners with self-control (SC; 8). Participants in the two learning groups (P-L and SC groups) completed a serial-timing task with a goal time of 2500 ms. Absolute error data on KR and no-KR trials along with self-reports indicate that participants with self-control preferred KR after good trials and peers preferred to provide KR after both good and bad trials equally. Results from the delayed retention test indicated that peer-controlled learners were more consistent (i.e., in terms of variable error) than the self-control group.

  10. A novel anti-neuroinflammatory pyridylimidazole compound KR-31360.

    Science.gov (United States)

    Ock, Jiyeon; Kim, Sangseop; Yi, Kyu-Yang; Kim, Nak-Jung; Han, Hyung Soo; Cho, Je-Yoel; Suk, Kyoungho

    2010-02-15

    Excessive microglial activation with overexpression of proinflammatory cytokines and oxidative stress products is linked to the progression of several neurodegenerative diseases; therefore, suppression of microglial activation is a potential therapeutic approach against these diseases. Since nitric oxide (NO) is one of the major inflammatory mediators that are produced by activated microglia, inhibitory effects of novel synthetic compounds on microglial NO production were investigated. From the mouse microglia cell-based assays, an imidazo [4,5-b] pyridine compound KR-31360 was identified as an inhibitor of microglial NO production with an IC(50) value of 2 microM. Structure-activity relationship study indicated that 5-position of imidazo [4,5-b] pyridine ring is critical for the activity. KR-31360 also inhibited lipopolysaccharide (LPS)-induced secretion of tumor necrosis factor alpha (TNF-alpha) and transcription of TNF-alpha, interleukin-1 beta, and inducible nitric oxide synthase as well as activation of nuclear factor kappa B and mitogen-activated protein kinases. KR-31360 was neuroprotective by suppressing microglial neurotoxicity in a microglia-neuron coculture. The neuroprotective activity of the compound was most effective when microglia were pretreated with the compound prior to LPS challenge. The inhibitory effect of KR-31360 on microglial activation was further demonstrated in a mouse neuroinflammation model in vivo: compared to vehicle-injected animals, KR-31360 injection attenuated LPS-induced microglial activation as evidenced by isolectin B4 staining and proinflammatory gene expression of brain sections. DNA microarray analysis supported that KR-31360 targeted Toll-like receptor 4 pathways. In addition to being a new drug candidate against neuroinflammatory diseases, the compound may be a powerful tool for the better understanding of microglia biology and neuroinflammation.

  11. Cryptophane-Folate Biosensor for 129Xe NMR

    Science.gov (United States)

    2014-12-01

    2005) Head- to-tail peptide cyclodimerization by copper -catalyzed azide-alkyne cycloaddition. Angew. Chem., Int. Ed. Engl. 44, 2215−2220. (55...cryptophane biosensor was synthesized in 20 nonlinear steps, which included functionalization with folate recognition moiety, solubilizing peptide , and...carbonic anhydrases I or II.36 Another example included a peptide - labeled 129Xe biosensor by Schlundt et al. that produced a 1 ppm downfield shift upon

  12. Stark Broadening in Compact Stars: Xe VI Lines

    Indian Academy of Sciences (India)

    Milan S. Dimitrijević; Zoran Simić; Andjelka Kovačević; Aleksandar Valjarević; Sylvie Sahal-Bréchot

    2015-12-01

    We will consider Stark broadening of non hydrogenic spectral lines in the impact approximation in compact stars: pre-white dwarf and white dwarf atmospheres. In order to show an example, Stark broadening parameters have been calculated, using the impact semiclassical perturbation approach for four Xe VI spectral lines. Obtained results have been used to demonstrate the influence of Stark broadening in DA and DB white dwarf atmospheres.

  13. Electromagnetically induced absorption in metastable 83Kr atoms

    CERN Document Server

    Kale, Y B; Mishra, S R; Singh, S; Rawat, H S

    2015-01-01

    We report electromagnetically induced absorption (EIA) resonances of sub-natural linewidth (FWHM) in metastable noble gas 83Kr* atoms using degenerate two level schemes (DTLSs). This is the first observation of EIA effect in a metastable noble gas atoms. Using these spectrally narrow EIA signals obtained corresponding to the closed hyperfine transition from 4p55s[3/2]2 to 4p55p[5/2]3 hyperfine manifolds of 83Kr* atoms, we have measured the Lande's g-factor (gF) for the lower level (F = 13/2) of the closed transition accurately with small applied magnetic fields of few Gauss.

  14. High-Statistics β+ / EC -Decay Study of 122Xe

    Science.gov (United States)

    Jigmeddorj, Badamsambuu; S1292 Collaboration

    2016-09-01

    The Xe isotopes are centrally located in the Z > 50 , N vibrational structure influenced by proton subshell gaps, perhaps leading to shape-coexistence that could give rise to strong E 0 transitions. Recent work on 124Xe has established nearly identical quadrupole collectivity for the pairing vibrational 03+ band and the ground state band. However, in 122Xe, the 03+ state has not been firmly identified. A high-statistics 122Cs β+ / EC decay experiment to obtain detailed spectroscopic data for low-spin states was performed at the TRIUMF-ISAC facility using the 8 π γ-ray spectrometer and its auxiliary detectors including PACES, an array of five Si(Li) detectors, for conversion electron spectroscopy. The decay scheme has been considerably extended through a γ- γ coincidence analysis, and 0+ states have been identified via γ- γ angular correlations. This work supported by the Natural Sciences and Engineering Research Council of Canada and the National Research Council of Canada.

  15. Effects of knowledge of results (KR) frequency in the learning of a timing skill: absolute versus relative KR frequency.

    Science.gov (United States)

    Vieira, Márcio M; Ugrinowitsch, Herbert; Oliveira, Fernanda S; Gallo, Lívia G; Benda, Rodolfo N

    2012-10-01

    The interaction between the amount of practice and frequency of Knowledge of Results (KR) was investigated in a timing skill. In the acquisition phase the task involved 90 trials of releasing a knob and transporting three tennis balls from three near recipients to three far ones in a specific sequence and target time. The retention test performed 24 hr. later had the same sequence of transport but a new target time was required. In both phases, absolute error and standard deviation plus constant error was measured. The five groups differed in relation to frequency of KR and amount of practice. The results showed that intermediate frequencies as well as higher frequencies of KR elicited better performance during the retention test.

  16. Stellar laboratories. VIII. New Zr IV - VII, Xe IV - V, and Xe VII oscillator strengths and the Al, Zr, and Xe abundances in the hot white dwarfs G191-B2B and RE0503-289

    CERN Document Server

    Rauch, T; Quinet, P; Loebling, L; Hoyer, D; Werner, K; Kruk, J W; Demleitner, M

    2016-01-01

    For the spectral analysis of high-resolution and high-signal-to-noise spectra of hot stars, state-of-the-art non-local thermodynamic equilibrium (NLTE) model atmospheres are mandatory. These are strongly dependent on the reliability of the atomic data that is used for their calculation. To search for Zr and Xe lines in the ultraviolet (UV) spectra of G191-B2B and RE0503-289, new Zr IV-VII, Xe IV-V, and Xe VIII oscillator strengths were calculated. This allows for the first time, determination of the Zr abundance in white dwarf (WD) stars and improvement of the Xe abundance determinations. We calculated Zr IV-VII, Xe IV-V, and Xe VIII oscillator strengths to consider radiative and collisional bound-bound transitions of Zr and Xe in our NLTE stellar-atmosphere models for the analysis of their lines exhibited in UV observations of the hot WDs G191-B2B and RE0503-289. We identified one new Zr IV, 14 new Zr V, and ten new Zr VI lines in the spectrum of RE0503-289. Zr was detected for the first time in a WD. We mea...

  17. 关于蕴含Ar,s——可图序列的注记%On Potentially Ar,s-Graphic Sequences

    Institute of Scientific and Technical Information of China (English)

    李炯生; 尹建华

    2001-01-01

    In this paper,The criterion for a sequence π=(d1,…,dr,dr+1,…,dr+s,…,dn)of nonnegative integers with di≤n-1 being potentially Ar,s-graphic is obtained.%设G=(V(G),E(G))是n阶简单图,其顶点集V(G)={v1,…,vr,vr+1,…,vr+s,…,vn},π={d1,…,dr,dr+1,…,dr+s,…,dn}是G的度序列,且vi的度为dio称G具有性质Ar,s,如果{v1,…,vr,vr+1,…,vr+s}的导出子图是完全二部图Kr,s,且{v1,…,vr}和{vr+1,…,vr+s}是Kr,s顶点集的二部划分.序列π={d1,…,dr,dr+1,…,dr+s,…,dn}称为是蕴含Ar,s-可图的序列判别准则.

  18. Dmitri Krõmovist on saanud vaatemängumeister / Andres Laasik

    Index Scriptorium Estoniae

    Laasik, Andres, 1960-2016

    2006-01-01

    Vene lavastaja Dmitri Krõmovist ja tema lavastusest "Söör Vantes. Donki Hot" (Anatoli Vassiljevi Teater Draamakunstikool. Dmitri Krõmovi loomelaboratoorium), mida etendatakse festivalil "Talveöö unenägu 2006"

  19. On No-KR tests in motor learning, retention and transfer.

    Science.gov (United States)

    Russell, Daniel M; Newell, Karl M

    2007-02-01

    In this paper we examine the role of no-knowledge of results (KR) tests in motor learning, retention and transfer. A distinction is drawn between studies of KR and studies of other issues in motor learning that use a No-KR test. Arguments are presented against the currently received position that a No-KR test is an essential protocol to examine motor learning, although a No-KR test is most relevant in the few contexts where the outcome information is not naturally available. Perspectives are provided on the limited though proper role of No-KR tests in motor learning, retention and transfer and these are illustrated through experimental examples. It is proposed that the current restrictive interpretation of KR as only augmented outcome information is narrowing not only the context of KR research but also the study of motor learning in general.

  20. On kr-spaces and k-spaces%关于kr-空间与k-空间

    Institute of Scientific and Technical Information of China (English)

    恽自求

    2000-01-01

    本文给出具有局部可数闭k- 网的kr- 空间成为k- 空间的一个充要条件.此结果给林寿提出的问题作出一个回答.%In this paper, we givea necessary and sufficient condition for a regular kr-space X witha locally countable closed k-network to be a k-space and give ananswer to a question raised by Lin Shou.

  1. KR Aur - extremely high variations in optical bands

    Science.gov (United States)

    Boeva, S.; Latev, G.; Nikolov, Y.; Nikolov, P.; Nikolov, G.; Spassov, B.; Petrov, B.; Damljanovic, G.; Sekulic, M.; Zamanov, R.

    2017-03-01

    Since 2008, the cataclysmic variable star KR Aur is in deep minimum state with a short brightening in 2010. We performed photometric monitoring in 12 nights during the period August 2016 - February 2017 with the telescopes of Rozhen (Bulgaria), Belogradchik (Bulgaria) and Vidojevica (Serbia).

  2. Exploring hyperpolarized 83Kr by remotely detected NMR relaxometry

    Science.gov (United States)

    Cleveland, Zackary I.; Pavlovskaya, Galina E.; Stupic, Karl F.; LeNoir, Catherine F.; Meersmann, Thomas

    2006-01-01

    For the first time, a hyperpolarized (hp) noble gas with a nuclear electric quadrupole moment is available for high-field nuclear-magnetic-resonance (NMR) spectroscopy and magnetic-resonance imaging. Hp Kr83 (I=9/2) is generated by spin-exchange optical pumping and separated from the rubidium vapor used in the pumping process. Optical pumping occurs under the previously unstudied condition of high krypton gas densities. Signal enhancements of more than three orders of magnitude compared to the thermal equilibrium Kr83 signal at 9.4T magnetic-field strength are obtained. The spin-lattice relaxation of Kr83 is caused primarly by quadrupolar couplings during the brief adsorption periods of the krypton atoms on the surrounding container walls and significantly limits the currently obtained spin polarization. Measurements in macroscopic glass containers and in desiccated canine lung tissue at field strengths between 0.05 and 3T using remotely detected hp Kr83 NMR spectroscopy reveal that the longitudinal relaxation dramatically accelerates as the magnetic-field strength decreases.

  3. Difference flow and electrical conductivity measurements at the Olkiluoto site in Eurajoki, drillholes OL-KR54, OL-KR55, OL-KR55B and OL-KR47B

    Energy Technology Data Exchange (ETDEWEB)

    Komulainen, J.; Poellaenen, J.; Hurmerinta, E.; Ripatti, K. [Poeyry Finland Oy, Espoo (Finland)

    2012-04-15

    The Posiva Flow Log, Difference flow method (PFL DIFF) uses a flowmeter that incorporates a flow guide and can be used for relatively quick determinations of hydraulic conductivity and hydraulic head of fractures/fractured zones in drillholes. This report presents the principles of the method and the results of measurements carried out in drillholes OL-KR54, OL-KR55, OL-KR55B and OL-KR47B at the Olkiluoto investigation site between January 2011 and September 2011. The measuring programme employed was the same in all drillholes. The applied section lengths of the flow guide were either 2 m and 0.5 m. Flow into the drillhole or from the drillhole to the bedrock was measured within the section length. The measurements were carried out in both pumped and natural (i.e. un-pumped) conditions. The transmissivity and hydraulic head of zones were calculated from the flow and pressure results. The device used includes a sensor for single point resistance (SPR). SPR was measured in connection with the flow measurements. The electrical conductivity (EC) of fracture-specific water was measured in chosen fractures. Fractures were selected on the basis of the measured flow from fractures into the drillhole. The drillhole flow (flow along the drillhole) was measured in conjunction with drillhole EC measurements. (orig.)

  4. Real bundle gerbes, orientifolds and twisted KR-homology

    CERN Document Server

    Hekmati, Pedram; Szabo, Richard J; Vozzo, Raymond F

    2016-01-01

    We introduce a notion of Real bundle gerbes on manifolds equipped with an involution. We elucidate their relation to Jandl gerbes and prove that they are classified by their Real Dixmier-Douady class in Grothendieck's equivariant sheaf cohomology. We show that the Grothendieck group of Real bundle gerbe modules is isomorphic to twisted KR-theory for a torsion Real Dixmier-Douady class. Building on the Baum-Douglas model for K-homology and the orientifold construction in string theory, we introduce geometric cycles for twisted KR-homology groups using Real bundle gerbe modules. We prove that this defines a real-oriented generalised homology theory dual to twisted KR-theory for Real closed manifolds, and more generally for Real finite CW-complexes, for any Real Dixmier-Douady class. This is achieved by defining an explicit natural transformation to analytic twisted KR-homology and proving that it is an isomorphism. Our constructions give a new framework for the classification of orientifolds in string theory, p...

  5. Long storage times for hyperpolarized 129Xe and precise measurement of its absolute polarization

    Energy Technology Data Exchange (ETDEWEB)

    Repetto, Maricel; Zimmer, Stefan; Karpuk, Sergei; Bluemler, Peter; Heil, Werner [Johannes Gutenberg Universitaet, Institut fuer Physik. Staudingerweg 7 55099, Mainz (Germany)

    2014-07-01

    Applications of hyperpolarized (HP) 129Xe in medical research and fundamental physics experiments increased significantly in recent years. All uses profit from high degrees of polarization (PXe) which not only needs to be generated but also preserved during transport and storage. PXe is usually determined via comparison of the NMR signals from HP Xe with the NMR signal of thermally polarized H2O or Xe. All these procedures have experimental errors which are hard to eliminate. We present a simple method for the measurement of absolute PXe which best resolution is 0.6 % together with wall storage times > 12 hs using a homebuilt, mobile Xe polarizer.

  6. Mass and Double-Beta-Decay Q Value of Xe136

    Science.gov (United States)

    Redshaw, Matthew; Wingfield, Elizabeth; McDaniel, Joseph; Myers, Edmund G.

    2007-02-01

    The atomic mass of Xe136 has been measured by comparing cyclotron frequencies of single ions in a Penning trap. The result, with 1 standard deviation uncertainty, is M(Xe136)=135.907 214 484 (11) u. Combined with previous results for the mass of Ba136 [Audi, Wapstra, and Thibault, Nucl. Phys. A 729, 337 (2003)NUPABL0375-947410.1016/j.nuclphysa.2003.11.003], this gives a Q value (M[Xe136]-M[Ba136])c2=2457.83(37)keV, sufficiently precise for ongoing searches for the neutrinoless double-beta decay of Xe136.

  7. Determination of the separation efficiencies of a single-stage cryogenic distillation setup to remove krypton out of xenon by using a {sup 83m}Kr tracer method

    Energy Technology Data Exchange (ETDEWEB)

    Rosendahl, S., E-mail: rosendahl@wwu.de; Brown, E.; Fieguth, A.; Huhmann, C.; Murra, M.; Weinheimer, C. [Institut für Kernphysik, Wilhelm-Klemm Straße 09, 48149 Münster (Germany); Cristescu, I. [Karlsruher Institut für Technologie, Hermann Von Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Lebeda, O. [Nuclear Physics Institute, Czech Academy of Sciences, CZ 250 68 Řež (Czech Republic)

    2015-11-15

    The separation of krypton and xenon is of particular importance for the field of direct dark matter search with liquid xenon detectors. The intrinsic contamination of the xenon with radioactive {sup 85}Kr makes a significant background for these kinds of low count-rate experiments and has to be removed beforehand. This can be achieved by cryogenic distillation, a technique widely used in industry, using the different vapor pressures of krypton and xenon. In this paper, we present an investigation on the separation performance of a single stage distillation system using a radioactive {sup 83m}Kr-tracer method. The separation characteristics under different operation conditions are determined for very low concentrations of krypton in xenon at the level of {sup 83m}Kr/Xe = 1.9 ⋅ 10{sup −15}, demonstrating, that cryogenic distillation in this regime is working. The observed separation is in agreement with the expectation from the different volatilities of krypton and xenon. This cryogenic distillation station is the first step on the way to a multi-stage cryogenic distillation column for the next generation of direct dark matter experiment XENON1T.

  8. An Atom Trap Trace Analysis System for Measuring Krypton Contamination in Xenon Dark Matter Detectors

    CERN Document Server

    Aprile, Elena; Loose, Andre; Goetzke, Luke W; Zelevinsky, Tanya

    2013-01-01

    We have developed an atom trap trace analysis (ATTA) system to measure Kr in Xe at the part per trillion (ppt) level, a prerequisite for the sensitivity achievable with liquid xenon dark matter detectors beyond the current generation. Since Ar and Kr have similar laser cooling wavelengths, the apparatus has been tested with Ar to avoid contamination prior to measuring Xe samples. A radio-frequency (RF) plasma discharge generates a beam of metastable Ar which is optically collimated, slowed, and trapped using standard magneto-optical techniques. We detect the fluorescence of single trapped $^{40}$Ar atoms with a signal to noise ratio of 5. The measured system efficiency of $3 \\times 10^{-9}$ for Ar corresponds to an expected Kr in Xe sensitivity at the ppt level.

  9. High-accuracy mass measurements of neutron-rich Kr isotopes

    CERN Document Server

    Delahaye, P; Blaum, K; Carrel, F; George, S; Herfurth, F; Herlert, A; Kellerbauer, A G; Kluge, H J; Lunney, D; Schweikhard, L; Yazidjian, C

    2006-01-01

    The atomic masses of the neutron-rich krypton isotopes 84,86-95Kr have been determined with the tandem Penning trap mass spectrometer ISOLTRAP with uncertainties ranging from 20 to 220 ppb. The masses of the short-lived isotopes 94Kr and 95Kr were measured for the first time. The masses of the radioactive nuclides 89Kr and 91Kr disagree by 4 and 6 standard deviations, respectively, from the present Atomic-Mass Evaluation database. The resulting modification of the mass surface with respect to the two-neutron separation energies as well as implications for mass models and stellar nucleosynthesis are discussed.

  10. 40Ar/39Ar age calibration against counted annuallayers

    DEFF Research Database (Denmark)

    Storey, Michael; Stecher, Ole

    2008-01-01

    worth exploring for an improved absolute age basis for the 40Ar/39Ar system is through cross-calibration with counted annual layers (e.g. tree rings, varves and ice cores). North Atlantic Ash Zone (NAAZ) II is found within the dated part of the annual Greenland ice core record. NAAZ II has been...

  11. Fine structure of the pygmy dipole resonance in (136)Xe.

    Science.gov (United States)

    Savran, D; Fritzsche, M; Hasper, J; Lindenberg, K; Müller, S; Ponomarev, V Yu; Sonnabend, K; Zilges, A

    2008-06-13

    The photoresponse of the semimagic N=82 nucleus (136)Xe was measured up to the neutron separation energy S(n) using the (gamma, gamma') reaction. A concentration of strong dipole excitations is observed well below S(n) showing a fragmented resonancelike structure. Microscopic calculations in the quasiparticle phonon model including complex configurations of up to three phonons agree well with the experimental data in the total integrated strength, in the shape and the fragmentation of the resonance, which allows us to draw conclusions on the damping mechanism of the pygmy dipole resonance.

  12. Low-lying quadrupole collectivity in {sup 136}Xe

    Energy Technology Data Exchange (ETDEWEB)

    Stahl, Christian; Leske, Joerg; Pietralla, Norbert; Reese, Michael [Institut fuer Kernphysik, Technische Universitaet Darmstadt (Germany); Bazzacco, Dino; Farnea, Enrico [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Gadea, Andres [Instituto de Fisica Corpuscular, CSIC-Universitat de Valencia, Valencia (Spain); Gottardo, Andrea [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro (Italy); Dipartimento di Fisica e Astronomia dell' Universita degli Studi di Padova, Padova (Italy); John, Philipp Rudolf; Michelagnoli, Caterina [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Dipartimento di Fisica e Astronomia dell' Universita degli Studi di Padova, Padova (Italy); Valiente-Dobon, Jose Javier [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro (Italy)

    2015-07-01

    We present recent results from our investigation of low-lying quadrupole collectivity in the semi-magic N=82 nucleus {sup 136}Xe. An experiment was performed at the Legnaro National Laboratory employing the AGATA demonstrator. Level-lifetimes and B(E2, 0{sup +}{sub 1}→2{sup +}{sub i})-values were determined from Coulomb excitation and by the continuous-angle DSA method exploiting AGATA's position resolution. 2{sup +}{sub i} - states up to i=7 were excited and analyzed.

  13. Summary and frequency of KR presentation effects on retention of a motor skill.

    Science.gov (United States)

    Sidaway, B; Moore, B; Schoenfelder-Zohdi, B

    1991-03-01

    This experiment investigates the recent proposal of Schmidt, Young, Swinnen, and Shapiro (1989) that summary knowledge of results (KR) improves skill retention. In Schmidt et al.'s experiment, however, summary length varied concomitantly with the frequency of KR presentation. The current investigation held KR presentation frequency constant while manipulating the number of trials seen in the summary KR display. Subjects were required to perform a timing task on a linear slide. Five groups (n = 12) of subjects participated in acquisition trials then in 10-min and 2-day delayed no-KR retention tests. In 4 conditions, subjects completed each acquisition block without any KR, but following each block they received KR on either 15, 7, 3, or 1 of the 15 trials performed in that block. In the final condition subjects received immediate KR. Analysis of the absolute constant error (magnitude of CE) data for acquisition revealed all groups improved with practice and the immediate KR group performed better than all the summary groups which in turn did not differ significantly. Analysis of the magnitude of CE retention data found performance to be worse on the 2-day retention test for all groups. The effect of condition was significant. The 1/1 group had lower error scores than all other groups, which in turn were not significantly different. Analyses of variable error (VE) revealed only that VE decreased with practice. These findings suggest frequency of KR presentation may be the basis for the summary KR effect found by Schmidt et al. (1989).

  14. Interactions between xenon and phospholipid bicelles studied by 2H/ 129Xe/ 131Xe NMR and optical pumping of nuclear spins

    Science.gov (United States)

    Li, Xiaoxia; Newberry, Caitlin; Saha, Indrajit; Nikolaou, Panayiotis; Whiting, Nicholas; Goodson, Boyd M.

    2006-02-01

    The interactions between xenon and DMPC/DHPC bicelles ( q = 3.5%, 7.5% w/v) were studied via 2H, 129Xe, 131Xe, and optically enhanced 129Xe NMR. The chemical shifts, linewidths, and quadrupolar couplings of the xenon/bicelle NMR signals were correlated with different regions of the bicellar phase diagram. The addition of xenon (<70 mM) was observed to reduce the temperature-onset of bicelle alignment by several degrees, in quantitative agreement with effects previously observed with chloroform; however, the stable liquid-crystalline range was not significantly reduced. Preliminary laser-polarized xenon/bicelle studies yielded 129Xe T1 values of ˜120 s, long enough to permit a variety of planned experiments.

  15. I-Xe Analysis of a Magnetic Separate from Lodranite GRA95209

    Science.gov (United States)

    Whitby, J. A.; Busemann, H.; Eugster, O.; Holland, G.; Gilmour, J. D.

    2002-03-01

    I-Xe dating of a magnetic mineral separate from lodranite GRA95209 suggests that peak temperatures (and therefore melt migration) occurred early, at least a few million years before closure of the I-Xe system in phosphates from Acapulco.

  16. The I-Xe System in Lodranites Suggests Impact-related Rapid Cooling

    Science.gov (United States)

    Crowther, S. A.; Whitby, J. A.; Busfield, A.; Holland, G.; Busemann, H.; Gilmour, J. D.

    2009-03-01

    The I-Xe system of three lodranites has been investigated. Two metal and one silicate separate from GRA 95209 gave ages consistent with each other (and the I-Xe age of Acapulco feldspar), suggesting the parent material underwent a period of rapid cooling.

  17. Compensation for geometric changes during monitoring of 133Xe washout from subcutaneous adipose tissue

    DEFF Research Database (Denmark)

    Bülow, J; Madsen, J

    1975-01-01

    A method is described for automatic compensation of changes in geometry during monitoring of 133Xe-washout curves from subcutaneous depots. A 99mTc source is placed on the skin over the 133Xe depot, and both isotopes are counted simultaneously. Variations in the 99mTc activity (corrected for radi...

  18. T-Duality for Orientifolds and Twisted KR-Theory

    Science.gov (United States)

    Doran, Charles; Méndez-Diez, Stefan; Rosenberg, Jonathan

    2014-08-01

    D-brane charges in orientifold string theories are classified by the KR-theory of Atiyah. However, this is assuming that all O-planes have the same sign. When there are O-planes of different signs, physics demands a "KR-theory with a sign choice" which up until now has not been studied by mathematicians (with the unique exception of Moutuou, who did not have a specific application in mind). We give a definition of this theory and compute it for orientifold theories compactified on S 1 and T 2. We also explain how and why additional "twisting" is implemented. We show that our results satisfy all possible T-duality relationships for orientifold string theories on elliptic curves, which will be studied further in subsequent work.

  19. Possible shape phase transition in the heavy Kr isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Bucurescu, D.; Constantinescu, G.; Cutoiu, D.; Ivascu, M.; Zamfir, N.V. (Institutul de Fizica si Inginerie Nucleara, Bucharest (Romania))

    1981-06-01

    Potential energy surfaces of Kr isotopes computed in the variables (epsilon,..gamma..) are presented. They account qualitatively for the main features observed experimentally for the lighter isotopes and predict that a shape phase transition, similar to that known for the heavy (A of the order of 100) Sr and Zr nuclei, should be observed in the neutron-rich isotopes between the neutron numbers 58 and 60.

  20. Optical hyperpolarization and NMR detection of $^{129}$Xe on a microfluidic chip

    CERN Document Server

    Jimenez-Martinez, Ricardo; Rosenbluh, Michael; Donley, Elizabeth A; Knappe, Svenja; Seltzer, Scott J; Ring, Hattie L; Bajaj, Vikram S; Kitching, John

    2014-01-01

    Optically hyperpolarized $^{129}$Xe gas has become a powerful contrast agent in nuclear magnetic resonance (NMR) spectroscopy and imaging, with applications ranging from studies of the human lung to the targeted detection of biomolecules. Equally attractive is its potential use to enhance the sensitivity of microfluidic NMR experiments, in which small sample volumes yield poor sensitivity. Unfortunately, most $^{129}$Xe polarization systems are large and non-portable. Here we present a microfabricated chip that optically polarizes $^{129}$Xe gas. We have achieved $^{129}$Xe polarizations greater than 0.5$\\%$ at flow rates of several microliters per second, compatible with typical microfluidic applications. We employ in situ optical magnetometry to sensitively detect and characterize the $^{129}$Xe polarization at magnetic fields of 1 $\\mu$T. We construct the device using standard microfabrication techniques, which will facilitate its integration with existing microfluidic platforms. This device may enable the...

  1. Programming A Molecular Relay for Ultrasensitive Biodetection through 129 Xe NMR

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yanfei [Department of Chemistry, University of Pennsylvania, 231 South 34th Street Philadelphia PA 19104-6323 USA; Roose, Benjamin W. [Department of Chemistry, University of Pennsylvania, 231 South 34th Street Philadelphia PA 19104-6323 USA; Philbin, John P. [Department of Chemistry, University of Pennsylvania, 231 South 34th Street Philadelphia PA 19104-6323 USA; Doman, Jordan L. [Department of Chemistry, University of Pennsylvania, 231 South 34th Street Philadelphia PA 19104-6323 USA; Dmochowski, Ivan J. [Department of Chemistry, University of Pennsylvania, 231 South 34th Street Philadelphia PA 19104-6323 USA

    2015-12-21

    We reported a supramolecular strategy for detecting specific proteins in complex media by using hyperpolarized 129Xe NMR. A cucurbit[6]uril (CB[6])-based molecular relay was programmed for three sequential equilibrium conditions by designing a two-faced guest (TFG) that initially binds CB[6] and blocks the CB[6]–Xe interaction. Moreover, the protein analyte recruits the TFG and frees CB[6] for Xe binding. TFGs containing CB[6]- and carbonic anhydrase II (CAII)-binding domains were synthesized in one or two steps. X-ray crystallography confirmed TFG binding to Zn2+ in the deep CAII active-site cleft, which precludes simultaneous CB[6] binding. The molecular relay was reprogrammed to detect avidin by using a different TFG. Finally, Xe binding by CB[6] was detected in buffer and in E. coli cultures expressing CAII through ultrasensitive 129Xe NMR spectroscopy.

  2. MARMOT simulations of Xe segregation to grain boundaries in UO2

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Anders D. [Los Alamos National Laboratory; Tonks, Michael [Idaho National Laboratory; Casillas, Luis [Los Alamos National Laboratory; Millett, Paul [Idaho National Laboratory; Vyas, Shyam [Los Alamos National Laboratory; Uberuaga, Blas P. [Los Alamos National Laboratory; Nerikar, Pankaj [IBM

    2012-06-20

    Diffusion of Xe and U in UO{sub 2} is controlled by vacancy mechanisms and under irradiation the formation of mobile vacancy clusters is important. We derive continuum thermodynamic and diffusion models for Xe and U in UO{sub 2} based on the vacancy and cluster diffusion mechanisms established from recent density functional theory (DFT) calculations. Segregation of defects to grain boundaries in UO{sub 2} is described by combining the diffusion model with models of the interaction between Xe atoms and vacancies with grain boundaries derived from separate atomistic calculations. The diffusion and segregation models are implemented in the MOOSE/MARMOT (MBM) finite element (FEM) framework and we simulate Xe redistribution for a few simple microstructures. In this report we focus on segregation to grain boundaries. The U or vacancy diffusion model as well as the coupled diffusion of vacancies and Xe have also been implemented, but results are not included in this report.

  3. Shape determination in Coulomb excitation of $^{72}$Kr

    CERN Multimedia

    Reiter, P; Kruecken, R; Paul, E S; Wadsworth, R; Heenen, P

    Nuclei with oblate shapes at low spins are very special in nature because of their rarity. Both theoretical and experimental shape co-existence studies in the mass 70 region for near proton drip-line nuclei suggest $^{72}$Kr to be the unique case with oblate low-lying and prolate high-lying levels. However, there is no direct experimental evidence in the literature to date for the oblate nature predicted for the first 2$^+$ state in $^{72}$Kr. We propose to determine the sign of the spectroscopic quadrupole moment of this state via the re-orientation effect in a low-energy Coulomb excitation measurement. In the inelastic excitation of the 2$^+$ state in $^{72}$Kr beam of 3.1 MeV/u with an intensity of 800 pps at REX-ISOLDE impinging on $^{104}$Pd target, the re-orientation effect plays a significant role. The cross section measurement for the 2$^+$ state should thus allow the model-independent determination of the sign of the quadrupole moment unambiguously and will shed light on the co-existing prolate and o...

  4. Kr ion irradiation study of the depleted-uranium alloys

    Science.gov (United States)

    Gan, J.; Keiser, D. D.; Miller, B. D.; Kirk, M. A.; Rest, J.; Allen, T. R.; Wachs, D. M.

    2010-12-01

    Fuel development for the reduced enrichment research and test reactor (RERTR) program is tasked with the development of new low enrichment uranium nuclear fuels that can be employed to replace existing high enrichment uranium fuels currently used in some research reactors throughout the world. For dispersion type fuels, radiation stability of the fuel-cladding interaction product has a strong impact on fuel performance. Three depleted-uranium alloys are cast for the radiation stability studies of the fuel-cladding interaction product using Kr ion irradiation to investigate radiation damage from fission products. SEM analysis indicates the presence of the phases of interest: U(Al, Si) 3, (U, Mo)(Al, Si) 3, UMo 2Al 20, U 6Mo 4Al 43 and UAl 4. Irradiations of TEM disc samples were conducted with 500 keV Kr ions at 200 °C to ion doses up to 2.5 × 10 19 ions/m 2 (˜10 dpa) with an Kr ion flux of 10 16 ions/m 2/s (˜4.0 × 10 -3 dpa/s). Microstructural evolution of the phases relevant to fuel-cladding interaction products was investigated using transmission electron microscopy.

  5. The Laser-assisted photoelectric effect of He, Ne, Ar and Xe in intense extreme ultraviolet and infrared laser fields

    Science.gov (United States)

    Hayden, P.; Dardis, J.; Hough, P.; Richardson, V.; Kennedy, E. T.; Costello, J. T.; Düsterer, S.; Redlin, H.; Feldhaus, J.; Li, W. B.; Cubaynes, D.; Meyer, M.

    2016-02-01

    In this paper, we report results on two-colour above-threshold ionisation, where extreme ultraviolet pulses of femtosecond duration were synchronised to intense infrared laser pulses of picosecond duration, in order to study the laser-assisted photoelectric effect of atomic helium, neon, krypton and xenon which leads to the appearance of characteristic sidebands in the photoelectron spectra. The observed trends are found to be well described by a simple model based on the soft-photon approximation, at least for the relatively low optical intensities of up to ? employed in these early experiments.

  6. Reinvestigation of {sup 85}Kr branching in the light of new {sup 82,} {sup 84,} {sup 86}Kr neutron capture cross section measurements

    Energy Technology Data Exchange (ETDEWEB)

    Mutti, Paolo [Institut Laue Langevin, Grenoble Cedex (France); Beer, Hermann [Institut fuer Kernphysik, Forschungszentrum Karlsruhe, Karlsruhe (Germany); Brusegan, Antonio; Corvi, Franco [Institute for Reference Materials and Measurements, Retieseweg, Geel (Belgium)

    2002-08-01

    High resolution neutron capture cross section measurements of 3 stable krypton isotopes, {sup 82}Kr, {sup 84}Kr and {sup 86}Kr, have been performed at the Geel Linear Accelerator (GELINA) on both resolved and unresolved resonance region. In addition, a total cross section measurement on {sup 84}Kr has also been performed in the energy range from 1 eV up to 120 kev. Accurate values of the Maxwellian-averaged capture cross section have been derived for all isotopes for stellar temperatures ranging from kT=5 up to 100 keV. A re-investigation of the s-process in the mass region around the prominent branching at {sup 85}Kr has been undertaken in the light of our new results. (author)

  7. Short KR-12 analogs designed from human cathelicidin LL-37 possessing both antimicrobial and antiendotoxic activities without mammalian cell toxicity.

    Science.gov (United States)

    Jacob, Binu; Park, Il-Seon; Bang, Jeong-Kyu; Shin, Song Yub

    2013-11-01

    KR-12 (residues 18-29 of LL-37) was known to be the smallest peptide of human cathelicidin LL-37 possessing antimicrobial activity. In order to optimize α-helical short antimicrobial peptides having both antimicrobial and antiendotoxic activities without mammalian cell toxicity, we designed and synthesized a series of KR-12 analogs. Highest hydrophobic analogs KR-12-a5 and KR-12-a6 displayed greater inhibition of lipopolysaccharide (LPS)-stimulated tumor necrosis factor-α production and higher LPS-binding activity. We have observed that antimicrobial activity is independent of charge, but LPS neutralization requires a balance of hydrophobicity and net positive charge. Among KR-12 analogs, KR-12-a2, KR-12-a3 and KR-12-a4 showed much higher cell specificity for bacteria over erythrocytes and retained antiendotoxic activity, relative to parental LL-37. KR-12-a5 displayed the strongest antiendotoxic activity but almost similar cell specificity as compared with LL-37. Also, these KR-12 analogs (KR-12-a2, KR-12-a3, KR-12-a4 and KR-12-a5) exhibited potent antimicrobial activity (minimal inhibitory concentration: 4 μM) against methicillin-resistant Staphylococcus aureus. Taken together, these KR-12 analogs have the potential for future development as a novel class of antimicrobial and anti-inflammatory therapeutic agents.

  8. Ultrasensitive resonance ionization mass spectrometer for evaluating krypton contamination in xenon dark matter detectors

    Energy Technology Data Exchange (ETDEWEB)

    Iwata, Y., E-mail: iwata.yoshihiro@jaea.go.jp [Experimental Fast Reactor Department, Oarai Research and Development Center, Japan Atomic Energy Agency, 4002 Narita, Oarai, Ibaraki 311-1393 (Japan); Sekiya, H. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Ito, C. [Experimental Fast Reactor Department, Oarai Research and Development Center, Japan Atomic Energy Agency, 4002 Narita, Oarai, Ibaraki 311-1393 (Japan)

    2015-10-11

    An ultrasensitive resonance ionization mass spectrometer that can be applied to evaluate krypton (Kr) contamination in xenon (Xe) dark matter detectors has been developed for measuring Kr at the parts-per-trillion (ppt) or sub-ppt level in Xe. The gas sample is introduced without any condensation into a time-of-flight mass spectrometer through a pulsed supersonic valve. Using a nanosecond pulsed laser at 212.6 nm, {sup 84}Kr atoms in the sample are resonantly ionized along with other Kr isotopes. {sup 84}Kr ions are then mass separated and detected by the mass spectrometer in order to measure the Kr impurity concentration. With our current setup, approximately 0.4 ppt of Kr impurities contained in pure argon (Ar) gas are detectable with a measurement time of 1000 s. Although Kr detection sensitivity in Xe is expected to be approximately half of that in Ar, our spectrometer can evaluate Kr contamination in Xe to the sub-ppt level.

  9. Calculations of S$_{2n}$ and $\\delta<$r$^{2}>$ on long series of Kr, Rb, Sr and Xe, Cs, Ba isotopes

    CERN Document Server

    Epherre-Rey-Campagnolle, Marcelle; Campi, X

    1981-01-01

    The density dependent Hartree-Fock method has been used to study the variation of the two neutron separation energies (S/sub 2n/) and of the mean square charge radii ( delta (r/sup 2/)). Correlations between anomalous S/sub 2n/, delta (r/sup 2/) and deformations have been analyzed. (5 refs).

  10. Investigating correlated few-electron dynamics and QED contributions by means of dielectronic recombination into highly-charged Fe, Kr, Xe, Ba, W, and Hg ions

    Energy Technology Data Exchange (ETDEWEB)

    Harman, Z.; Maeckel, V.; Martinez Gonzalez, A.J.; Crespo Lopez-Urrutia, J.R.; Jentschura, U.D.; Keitel, C.H.; Postavaru, O.; Tawara, H.; Ullrich, J. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Artemyev, A.N.; Tupitsyn, I.I. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); St. Petersburg State University, Oulianovskaya 1, 198504 St. Petersburg (Russian Federation)

    2007-07-01

    The photorecombination of highly charged He- to B-like ions has been explored in the atomic number range Z=26 to 80 with the Heidelberg electron beam ion trap. The energies of state-selected dielectronic recombination (DR) resonances were determined over the KLL region. At the present level of experimental accuracy, it becomes possible to make a detailed comparison to vario us theoretical approaches and methods, all of which include relativistic and quantum electrodynamic (QED) effects. Theoretical resonance energies for KLL DR are calculated by various means. The comparison of theoretical values with the experimental energies shows a good overall agreement. Few discrepancies are found in specific recombination resonances for initially Li- and Be-like heavy ions.

  11. Neutron-hole states in 45Ar from p(46Ar,d)45Ar reactions

    CERN Document Server

    Lu, F; Tsang, M B; Bazin, D; Coupland, D; Henzl, V; Henzlova, D; Kilburn, M; Lynch, W G; Rogers, A M; Sanetullaev, A; Sun, Z Y; Youngs, M; Charity, R J; Sobotka, L G; Famiano, M; Hudan, S; Horoi, M; Ye, Y L

    2013-01-01

    To improve the effective interactions in the pf shell, it is important to measure the single particle- and hole- states near the N=28 shell gap. In this paper, the neutron spectroscopic factors of hole-states from the unstable neutron-rich 45Ar (Z=18, N=27) nucleus have been studied using 1H(46Ar, 2H)45Ar transfer reaction in inverse kinematics. Comparison of our results with the particle-states of 45Ar produced in 2H(44Ar, H)45Ar reaction shows that the two reactions populate states with different angular momentum. Using the angular distributions, we are able to confirm the spin assignments of four low-lying states of 45Ar. These are the ground state (f7/2), the first-excited (p3/2), the s1/2 and the d3/2 states. While large basis shell model predictions describe spectroscopic properties of the ground and p3/2 states very well, they fail to describe the s1/2 and d3/2 hole-states.

  12. Ars Poetica : [luuletused] / Mats Traat

    Index Scriptorium Estoniae

    Traat, Mats, 1936-

    2008-01-01

    Sisu: Ars poetica ; Veepeegel ; Kontrollõed ; Mandariiniriik ; Nikolai Siamashvili (1888-1911) ; Kolmekümne kolmas aasta ; Kiri linast 1966 ; Italmaz Nuriyev ; Rudolf Rimmelile mõeldes ; Gennadi Aigi

  13. Pulsed discharge production Ar* metastables

    Science.gov (United States)

    Han, Jiande; Heaven, Michael C.; Emmons, Daniel; Perram, Glen P.; Weeks, David E.; Bailey, William F.

    2016-03-01

    The production of relatively high densities of Ar* metastables (>1012 cm-3) in Ar/He mixtures, at total pressures close to 1 atm, is essential for the efficient operation of an optically pumped Ar* laser. We have used emission spectroscopy and diode laser absorption spectroscopy measurements to observe the production and decay of Ar* in a parallel plate pulsed discharge. With discharge pulses of 1 μs duration we find that metastable production is dominated by processes occurring within the first 100 ns of the gas break-down. Application of multiple, closely spaced discharge pulses yields insights concerning conditions that favor metastable production. This information has been combined with time-resolved measurements of voltage and current. The experimental results and preliminary modeling of the discharge kinetics are presented.

  14. The smallest degree sum that yields potentially Kr,r-graphic sequences

    Institute of Scientific and Technical Information of China (English)

    尹建华; 李炯生

    2002-01-01

    We consider a variation of a classical Turán-type extremal problem as follows: Determine the smallest even integer σ(Kr,r, n) such that every n-term graphic sequence π = (d1, d2,..., dn) with term sum σ(π) = d1 + d2 +…+ dn ≥σ(Kr,r, n) is potentially Kr,r-graphic, where Kr,r is an r × r complete bipartite graph, i.e. πr has a realization G containing Kr,r as its subgraph. In this paper, the values σ(Kr,r,n) for even r and n ≥ 4r2 - r - 6 and for odd r and n ≥ 4r2 + 3r - 8 are determined.

  15. Pulmonary MRI contrast using Surface Quadrupolar Relaxation (SQUARE) of hyperpolarized (83)Kr.

    Science.gov (United States)

    Six, Joseph S; Hughes-Riley, Theodore; Lilburn, David M L; Dorkes, Alan C; Stupic, Karl F; Shaw, Dominick E; Morris, Peter G; Hall, Ian P; Pavlovskaya, Galina E; Meersmann, Thomas

    2014-01-01

    Hyperpolarized (83)Kr has previously been demonstrated to enable MRI contrast that is sensitive to the chemical composition of the surface in a porous model system. Methodological advances have lead to a substantial increase in the (83)Kr hyperpolarization and the resulting signal intensity. Using the improved methodology for spin exchange optical pumping of isotopically enriched (83)Kr, internal anatomical details of ex vivo rodent lung were resolved with hyperpolarized (83)Kr MRI after krypton inhalation. Different (83)Kr relaxation times were found between the main bronchi and the parenchymal regions in ex vivo rat lungs. The T1 weighted hyperpolarized (83)Kr MRI provided a first demonstration of surface quadrupolar relaxation (SQUARE) pulmonary MRI contrast.

  16. KR-31831, benzopyran derivative, inhibits VEGF-induced angiogenesis of HUVECs through suppressing KDR expression.

    Science.gov (United States)

    Park, Shi-Young; Seo, Eun-Hee; Song, Hyun Seok; Jung, Seung-Youn; Lee, Young-Kyoung; Yi, Kyu-Yang; Yoo, Sung-Eun; Kim, Yung-Jin

    2008-06-01

    Angiogenesis is important in the development and progression of cancer, therefore the therapeutic approach based on anti-angiogenesis may represent a promising therapeutic option. KR-31831 is a novel anti-ischemic agent. Previously, we reported the anti-angiogenic activity of KR-31831. In the present study we investigated the molecular mechanisms underlying anti-angiogenic activity of KR-31831. We show that KR-31831 inhibits vascular endothelial growth factor (VEGF)-induced proliferation and tube formation via release of intracellular Ca2+ and phosphorylation of extra-cellular regulated kinase 1/2 (Erk 1/2) in human umbilical vein endothelial cells (HUVECs). Moreover, the expression of VEGF receptor 2 (VEGFR2, known as Flk-1 or KDR) was reduced by the treatment of KR-31831. These results suggest that KR-31831 may have inhibitory effects on tumor angiogenesis through down-regulation of KDR expression.

  17. Possible Odd Parity State in {sup 128}Xe

    Energy Technology Data Exchange (ETDEWEB)

    Broman, L. [Department of Physics, Chalmers Univ. of Technology, Goeteborg (Sweden); Malmskog, S.G. [AB Atomenergi, Nykoeping (Sweden)

    1966-07-15

    Gamma lines in the decay of I have been measured by means of a Ge(Li) detector. The following gamma ray energies have been obtained: 442.5 {+-} 0.05, 526.5 {+-} 0.5, 742.4 {+-}1.0, 969.0 {+-} 1.0, and 1136.5 {+-}2.0 keV. The 1136.5 keV transition defines a level in {sup 128}Xe at 1579 {+-} 2 keV. From the log ft = 7.8 {+-} 0.3 of the ({beta}{sup -} feeding, this level is believed to have an odd parity. Upper limits of gamma ray intensities for transitions around eV are used to set a limit for the population of the expected 0{sup +} level originating from the two-phonon quadrupole vibration.

  18. Ba-ion extraction from a high pressure Xe gas for double-beta decay studies with EXO

    CERN Document Server

    Brunner, T; Sabourov, A; Varentsov, V L; Gratta, G; Sinclair, D

    2013-01-01

    An experimental setup is being developed to extract Ba ions from a high-pressure Xe gas environment. It aims to transport Ba ions from 10 bar Xe to vacuum conditions. The setup utilizes a converging-diverging nozzle in combination with a radio-frequency (RF) funnel to move Ba ions into vacuum through the pressure drop of several orders of magnitude. This technique is intended to be used in a future multi-ton detector investigating double-beta decay in $^{136}$Xe. Efficient extraction and detection of Ba ions, the decay product of Xe, would allow for a background-free measurement of the $^{136}$Xe double-beta decay.

  19. GraXe, graphene and xenon for neutrinoless double beta decay searches

    Energy Technology Data Exchange (ETDEWEB)

    Gómez-Cadenas, J.J.; Martín-Albo, J.; Monrabal, F.; Vidal, J. Muñoz [Instituto de Física Corpuscular (IFIC), CSIC and Universitat de Valencia, Calle Catedrático José Beltrán, 2, 46980 Valencia (Spain); Guinea, F. [Instituto de Ciencia de Materiales de Madrid (ICMM), CSIC, Calle Sor Juana Inés de la Cruz, 3, 28049 Madrid (Spain); Fogler, M.M. [Department of Physics, University of California San Diego, 9500 Gilman Drive, La Jolla, California 92093 (United States); Katsnelson, M.I., E-mail: gomez@mail.cern.ch, E-mail: paco.guinea@icmm.csic.es, E-mail: mfogler@ucsd.edu, E-mail: katsnel@sci.kun.nl, E-mail: justo.martin-albo@ific.uv.es, E-mail: francesc.monrabal@ific.uv.es, E-mail: jmunoz@ific.uv.es [Institute for Molecules and Materials, Radboud University Nijmegen, Heijendaalseweg 135, 6525 AJ Nijmegen (Netherlands)

    2012-02-01

    We propose a new detector concept, GraXe (to be pronounced as grace), to search for neutrinoless double beta decay in {sup 136}XE. GraXe combines a popular detection medium in rare-event searches, liquid xenon, with a new, background-free material, graphene. In our baseline design of GraXe, a sphere made of graphene-coated titanium mesh and filled with liquid xenon (LXe) enriched in the {sup 136}XE isotope is immersed in a large volume of natural LXe instrumented with photodetectors. Liquid xenon is an excellent scintillator, reasonably transparent to its own light. Graphene is transparent over a large frequency range, and impermeable to the xenon. Event position could be deduced from the light pattern detected in the photosensors. External backgrounds would be shielded by the buffer of natural LXe, leaving the ultra-radiopure internal volume virtually free of background. Industrial graphene can be manufactured at a competitive cost to produce the sphere. Enriching xenon in the isotope {sup 136}XE is easy and relatively cheap, and there is already near one ton of enriched xenon available in the world (currently being used by the EXO, KamLAND-Zen and NEXT experiments). All the cryogenic know-how is readily available from the numerous experiments using liquid xenon. An experiment using the GraXe concept appears realistic and affordable in a short time scale, and its physics potential is enormous.

  20. High-spin structure of yrast-band in 78Kr

    Indian Academy of Sciences (India)

    P K Joshi; R Palit; H C Jain; S Nagaraj; J A Sheikh

    2001-07-01

    Lifetime of levels up to 22+, have been measured in 78Kr and an oblate shape is assigned to the ground state using the CSM and the configuration dependent shell correction calculations. Calculations further show that 78Kr is highly -soft nucleus. The experimental t values coupled with theoretical calculations indicate an oblate shape for 78Kr at low spins and triaxial shape at higher spins

  1. Theoretical and experimental determination of the lowest excited states of the Kr*2 excimer

    Science.gov (United States)

    Gadea, F. X.; Spiegelmann, F.; Castex, M. C.; Morlais, M.

    1983-06-01

    The potential energy curves of the Kr*2 excimer dissociating into Kr (4s24p6 1S0)+Kr*(4s24p55s) are determined (i) theoretically from ab initio CI calculation and semiempirical SO coupling and (ii) experimentally from the temperature dependence of absorption profiles. The results are carefully examined with the help of theoretical simulation of line profiles using semiclassical or quantal models.

  2. Kartulisortide pikaaegne säilitamine krüomeetodil / Jaanika Edesi, Viive Rosenberg

    Index Scriptorium Estoniae

    Edesi, Jaanika

    2014-01-01

    Taimmaterjali krüosäilitus on hetkel uusim ja perspektiivikaim säilitusmeetod. Krüosäilituse all mõistetakse bioloogilise materjali säilitamist väga madalal temperatuuril elu- ja taastumisvõimelisena. Krüosäilitus toimub tavaliselt vedelas lämmastikus (-196 °C) või selle gaasilises faasis alla -150 °C kraadi.

  3. Study of the atmospheric 85Kr concentration growth in Gent between 1979 and 1999

    Science.gov (United States)

    Cauwels, P.; Buysse, J.; Poffijn, A.; Eggermont, G.

    2001-06-01

    Since 1979, the atmospheric 85Kr concentration has been monitored at our laboratory. The extensive data set, obtained in this way, has been statistically analysed to examine the degree of atmospheric 85Kr concentration growth over the past decades. The results were compared with those values found in the literature and with calculations of the 85Kr emission from the reprocessing plant of Cap La Hague.

  4. Fra viden til handling i rehabiliteringsindsatsen i forbindelse med kræft

    DEFF Research Database (Denmark)

    Adamsen, Lis; Rasmussen, Vibe; Brusgaard, Solvejg;

    Kræftens Bekæmpelse har vedtaget nye strategiske mål frem mod 2020. Det er et af måle-ne, at viden i højere grad skal omsættes til handling og mærkbare forbedringer for kræftpati-enter. Et af delmålene er at fremme effektiv overførsel af forskningsresultater til rehabilitering for kræftpatienter....

  5. Radiometric 81Kr dating identifies 120,000-year-old ice at Taylor Glacier, Antarctica

    OpenAIRE

    Buizert, Christo; Baggenstos, Daniel; Jiang, Wei; Purtschert, Roland; Petrenko, Vasilii V.; Lu, Zheng-Tian; Müller, Peter; Kuhl, Tanner; Lee, James,; Severinghaus, Jeffrey P.; Brook, Edward J.

    2014-01-01

    We present the first successful 81Kr-Kr radiometric dating of ancient polar ice. Krypton was extracted from the air bubbles in four ~350 kg polar ice samples from Taylor Glacier in the McMurdo Dry Valleys, Antarctica, and dated using Atom Trap Trace Analysis (ATTA). The 81Kr radiometric ages agree with independent age estimates obtained from stratigraphic dating techniques with a mean absolute age offset of 6 +/- 2.5 ka. Our experimental methods and sampling strategy are validated by 1) 85Kr ...

  6. Mass Measurement on the rp-Process Waiting Point 72Kr

    CERN Document Server

    Rodríguez, D; Audi, G; Äystö, J; Beck, D; Blaum, K; Bollen, G; Herfurth, F; Jokinen, A; Kellerbauer, A G; Kluge, H J; Oinonen, M; Schatz, H; Sauvan, E; Schwarz, S

    2004-01-01

    The mass of one of the three major waiting points in the astrophysical rp-process 72Kr was measured for the first time with the Penning trap mass spectrometer ISOLTRAP. The measurement yielded a relative mass uncertainty of delta m/m = 1.2x10-7 (delta m=8keV). Other Kr isotopes, also needed for astrophysical calculations, were measured with more than one order of magnitude improved accuracy. We use the ISOLTRAP masses of 72-74Kr to reanalyse the role of the 72Kr waiting point in the rp-process during X-ray bursts.

  7. Mass measurement on the rp-process waiting point {sup 72}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, D. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Kolhinen, V.S. [Jyvaeskylae Univ. (Finland); Audi, G. [CSNSM-IN2P3-Centre National de la Recherche Scientifique (CNRS), 91 - Orsay (FR)] [and others

    2004-06-01

    The mass of one of the three major waiting points in the astrophysical rp-process {sup 72}Kr was measured for the first time with the Penning trap mass spectrometer ISOLTRAP. The measurement yielded a relative mass uncertainty of {delta}m/m=1.2 x 10{sup -7} ({delta}m=8 keV). Other Kr isotopes, also needed for astrophysical calculations, were measured with more than one order of magnitude improved accuracy. We use the ISOLTRAP masses of{sup 72-74}Kr to reanalyze the role of the {sup 72}Kr waiting point in the rp-process during X-ray bursts. (orig.)

  8. Raman-Shifted XeCl Laser Development for a Spaceborne Blue-Green Source.

    Science.gov (United States)

    1982-02-01

    RAMAN-SHIFTED XeCI LASER DEVELOPMENT FOR A SPACEBORNE BLUE-GREEN SOURCE E. A. Stappaerts, M. J. Plummer, W. H. Long, Jr., S. J. Brosnan, H. Komine, and J...TITLE (and S.britJ S. TYPE OF REPORT 6 PEPIOD COVEPED Raman-Shifted XeCl Laser Development for a Technical Report Spaceborne Blue-Green Source: Interim...0.7% cm𔃻 312 nm I0 A 50 ns/DIV. FIGURE 5.3-1 MEASURED GAIN AND LOSS IN XeC1 87 81-34 AD-A133 078 RAMAN-SHIFED XEC LASER DEVELOPMENT FOR A

  9. Crystal structure of bis(fluorosulfato-κOxenon(II, Xe(SO3F2

    Directory of Open Access Journals (Sweden)

    Moritz Malischewski

    2015-04-01

    Full Text Available Thermally unstable Xe(SO3F2 has been prepared by the reaction of XeF2 with HSO3F. Single crystals were obtained from HSO3F by slow cooling in a sealed tube. The molecular structure is characterized by the Xe atom covalently bonded to two O atoms of two fluorosulfate tetrahedra in an almost linear fashion [O—Xe—O = 179.13 (4°]. The crystal packing is strongly influenced by intermolecular van der Waals forces.

  10. I-Pu-Xe dating and the relative ages of the earth and moon

    Science.gov (United States)

    Swindle, T. D.; Caffee, M. W.; Hohenberg, C. M.; Taylor, S. R.

    1986-01-01

    The ages of the earth and moon as determined by various chronometric systems are discussed with primary emphasis placed on the development of an I-Pu-Xe chronometer. Data on excess fission xenon are reviewed with attention given to the strengths and weaknesses of the assumptions required for lunar I-Pu-Xe chronometry. Using I-Pu-Xe dating, it is estimated that the retention of excess fission xenon in lunar samples began no more than 63 + or - 42 m.y. after the time of primitive meteorite formation.

  11. Purification and Detection of 39Ar in Groundwater Samples via Low-Level Counting

    Science.gov (United States)

    Mace, E. K.; Aalseth, C.; Brandenberger, J. M.; Humble, P.; Panisko, M.; Seifert, A.; Williams, R. M.

    2015-12-01

    Argon-39 can be used as a radiotracer to age-date groundwater aquifers to study recharge rates and to better understand the mean residence time, or age distributions, of groundwater. Argon-39 (with a half-life of 269 years) is created in the atmosphere by cosmic rays interacting with argon in the air (primarily 40Ar). The use of 39Ar as a radiotracer fills a gap in the age dating range which is currently covered by 3H/3He or 85Kr (1000 years); 39Ar fills the intermediate time scale range from 50-1000 years where the previously established radiotracers are not adequate. We will introduce the process for purifying and detecting 39Ar in ground water using ultra-low-background proportional counters (ULBPCs) at the shallow underground laboratory at Pacific Northwest National Laboratory. Argon-39 is detected through direct beta counting using ULBPCs loaded with a mixture of geologic argon (extracted from a carbon dioxide well with no measureable 39Ar activity) and methane, which enhances the sensitivity for 39Ar measurements. The ULBPCs have been shown to have a background count rate of 148 counts per day (cpd) in the energy range 3-400 keV when filled with 10 atm of P-10 counting gas (90% geologic Ar, 10% CH4). Initial demonstration samples were collected from groundwater aquifers in Fresno, California supported by the United States Geological Survey (USGS). A discussion of the sampling technique to degas the water from these wells and to then purify it for counting will be presented. In order to quantify the 39Ar contribution in the groundwater samples, the ULBPCs were characterized to determine two components: 1) the detector efficiency to modern levels of 39Ar, and 2) the remaining detector background (using geologic sourced argon which is free from 39Ar - no measureable 39Ar activity). These characterization results will be presented along with a discussion of the quantification of the 39Ar age of the demonstration measurements.

  12. Microscopic study of low-lying collectivebands in 77Kr

    Indian Academy of Sciences (India)

    K C Tripathy; R Sahu; S Mishra

    2006-02-01

    The structure of the collective bands in 77Kr is investigated within our deformed shell model (DSM) based on Hartree-Fock states. The different levels are classified into collective bands on the basis of their (2) values. The calculated = 5/2+ ground band agrees reasonably well with the experiment. An attempt has been made to study the structure of the 3-quasiparticle band based on large state in this nucleus. The calculated collective bands, the (2), and (1) values are compared with available experimental data. The nature of alignments in the low-lying bands is also analyzed.

  13. Paņēmieni skolēnu angļu valodas vārdu krājuma attīstībai 2. klasē

    OpenAIRE

    Tarando, Jūlija

    2015-01-01

    Diplomdarba „Paņēmieni skolēnu angļu valodas vārdu krājuma attīstībai 2. klasē” mērķis bija noskaidrot, kā angļu valoda vārdu krājuma attīstības paņēmieni palīdz pilnveidot skolēnu vārdu krājumu otrajā klasē. Literatūras teorētiskais apskats un 11 skolēnu atsevišķa gadījuma pētījums ar tādām datu vākšanas metodēm kā testi, aptauja un novērošana parādīja, ka gados jauniem skolēniem patīk mācīties jaunus vārdus ar attēliem, zīmējumiem un video, dzeju un dziesmām, pantomīmu, bet tādas tehnika...

  14. The I-Xe System in the IVA Iron Meteorite Steinbach

    Science.gov (United States)

    Pravdivtseva, O.; Meshik, A.; Hohenberg, C. M.

    2013-09-01

    Non-metallic phases from IVA Steinbach were separated and identified to be troilite, chromite, tridymite, and clino- and orthopyroxene. Xenon isotopic compositions are measured to identify possible iodine carrier phases suitable for the I-Xe dating.

  15. Improving the efficiency of a fluorescent Xe dielectric barrier light source using short pulse excitation

    Science.gov (United States)

    Beleznai, Sz; Mihajlik, G.; Maros, I.; Balázs, L.; Richter, P.

    2008-06-01

    Operation of a Xe dielectric barrier discharge lamp producing 147-172 nm VUV radiation is investigated both theoretically and experimentally. Xe gas pressure varies between 100 and 300 mbar, and the glass body of the lamp is coated with LAP (green) phosphor to convert radiation into the visible part of the spectrum. Simulation results predict improved discharge efficiencies reaching 67% when excited by a fast rise-time, short pulse (~200 ns) driving waveform. In this case most power deposited into the plasma efficiently produces Xe_2^\\ast excimers, while other energy dissipation processes (ion heating, e-Xe elastic collision) are kept at a low rate. Simulation and experimental results are compared in terms of discharge efficacy and show good agreement. A lamp efficacy value as high as 80 lm W-1 is demonstrated experimentally.

  16. I-Xe Dating of Small Chondrules from the Bjurbole Meteorite Using RELAX

    Science.gov (United States)

    Whitby, J. A.; Gilmour, J. D.; Ash, R. D.; Turner, G.

    1995-09-01

    Chondrules from the Bjurbole L4 meteorite have been widely used as a standard for I-Xe dating because of the good high temperature 129Xe-128Xe correlation [1] and small spread in their apparent ages determined by this technique. As part of an ongoing study [2,3], I-Xe analyses have been performed on several Bjurbole chondrules of sizes smaller than have hitherto been studied in order to determine if the chondrules and their constituent minerals are isochronous on a small scale. Use has been made of the ultra-sensitive RELAX resonance ionization xenon mass spectrometer, in conjunction with a laser probe for low-blank sample extraction [4] to analyse chondrule aliquots ranging in mass from 54 micrograms to 306 micrograms. Using data from five chondrules a spread of ages of 5Ma about the mean has been observed (129I t1/2=1.7x10^7 Ma), with specific excess (over the ordinary chondrite value [6]) 129Xe contents in the range 10x10^-12 to 1200x10^-12 cm3 STP g-1, consistent with previously reported values [2,5]. All the chondrules were completely molten at the highest laser probe powers used, hence it may be assumed that they were completely outgassed, in contrast to the data presented in [2]. This assumption is born out by the magnitudes of the specific excess 129Xe release. The smaller chondrules showed a sharper 129Xe release as a function of laser power as would be expected from the discussion of temperature gradients in [2]. Good isochrons were obtained except in the case of one sample (ABjC19) which contained very little excess 129Xe. The figure shows data from sample ABjC22, a 54 microgram aliquot from a 336 microgram chondrule. Excess 129Xe release and the ratio of excess 129Xe to excess 128Xe are plotted against extraction number (higher numbers correspond to higher temperatures). The fourth extraction gave rise to a 129Xe*/128Xe* ratio significantly different from the mean (error bars are one standard deviation) corresponding to an age apparently 3Ma older than

  17. Evaluation of Atypical Lymphocyte Warnings of Sysmex XE-4000 in Outpatient Children

    Institute of Scientific and Technical Information of China (English)

    Xueling GUO; Tingbo ZHANG; Maofan WANG

    2014-01-01

    This study aimed to evaluate the atypical lymphocyte warnings of Sysmex XE-4000 in outpatient children. [Method] Randomly 280 specimens of outpatient children were selected to analyze atypical lymphocytes with Sysmex XE-4000 and artificial smear microscopy simultaneously. [Result] With artificial smear microscopy as the gold standard, the atypical lymphocyte warnings of Sysmex XE-4000 in outpatient children exhibited a sensitivity of 97.4%, specificity of 69.3%, positive predictive value (PPV) of 55%, and negative predictive value (NPV) of 98.5%. [Conclusion] Sysmex XE-4000 shows a high sensitivity in atypical lymphocyte warnings, which can reduce the number of blood smears, improve the specificity of microscopy, and decline the labor intensity of inspection personnel. However, there are stil certain false positives to be confirmed by artificial microscopy.

  18. Characterization of lead nanoparticles formed by Shewanella sp. KR-12

    Science.gov (United States)

    Liu, Chien-Liang; Yen, Jui-Hung

    2016-01-01

    The bacterial strain KR-12 was isolated from river sediment in northeast Taiwan. 16S rRNA gene sequencing revealed that it belongs to the genus Shewanella. The strain can accumulate lead (Pb) and form Pb nanoparticles (PbNPs) on exposure to Pb(NO3)2 and sodium formate in HEPES buffer. On transmission electron microscopy (TEM), the KR-12-formed PbNPs were spherical in shape and ranged from 3 to 8 nm. The PbNPs formed a line or curved pattern on bacteria. In addition, one or more pilus-like structures elongated from the bacteria. In contrast, Shewanella oneidensis MR-1 and other bacteria could not form PbNPs pattern or pilus-like structure under the same conditions. High-resolution TEM combined with energy-dispersive X-ray spectroscopy demonstrated that these PbNPs primarily contained Pb and had an amorphous structure. This is the first report of the biosynthesis of PbNPs by a Shewanella species.

  19. Characterization of lead nanoparticles formed by Shewanella sp. KR-12

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chien-Liang; Yen, Jui-Hung, E-mail: sonny@ntu.edu.tw [National Taiwan University, Department of Agricultural Chemistry (China)

    2016-01-15

    The bacterial strain KR-12 was isolated from river sediment in northeast Taiwan. 16S rRNA gene sequencing revealed that it belongs to the genus Shewanella. The strain can accumulate lead (Pb) and form Pb nanoparticles (PbNPs) on exposure to Pb(NO{sub 3}){sub 2} and sodium formate in HEPES buffer. On transmission electron microscopy (TEM), the KR-12-formed PbNPs were spherical in shape and ranged from 3 to 8 nm. The PbNPs formed a line or curved pattern on bacteria. In addition, one or more pilus-like structures elongated from the bacteria. In contrast, Shewanella oneidensis MR-1 and other bacteria could not form PbNPs pattern or pilus-like structure under the same conditions. High-resolution TEM combined with energy-dispersive X-ray spectroscopy demonstrated that these PbNPs primarily contained Pb and had an amorphous structure. This is the first report of the biosynthesis of PbNPs by a Shewanella species.

  20. Internal conversion in highly-stripped {sup 83}Kr ions

    Energy Technology Data Exchange (ETDEWEB)

    Rehm, K.E.; Ahmad, I.; Gehring, J. [and others

    1995-08-01

    The transition probability per unit time for the decay of a nuclear level via internal conversion (IC), {lambda}IC, depends on the electron environment of the nucleus. For example, inner-shell conversion in highly-charged ions can change appreciably as electrons are successively removed from the ion. Magnetic dipole (Ml) transitions are especially sensitive to this effect since the internal conversion depends strongly on the electron density at the nucleus. Hence, measurements of {lambda}IC,q, the internal conversion rate in an ion with charge state q, can provide good tests of theoretical electron wave functions if the electron configuration in the ions is known. In a previous experiment, a new method which identifies charge-changing events during passage of ion beams through a magnetic spectrometer was used to determine {lambda}IC,q for the 14.4-keV isomer in {sup 57}Fe. This contribution reports measurements made using the same technique for the 9.4-keV isomer in {sup 83}Kr. A beam of {sup 83}Kr with energy 650 MeV bombarded a Au target with a thickness 300 {mu}g cm{sup -2}. Secondary scattered beams were accepted and analyzed by an Enge magnetic spectrometer. The numbers of excited nuclei decaying during passage through the spectrometer and their internal conversion rates were deduced from the pattern of events measured in the spectrometer focal plane.

  1. Study of Electric Monopole Transitions in $^{76,78}$Kr

    CERN Multimedia

    2002-01-01

    In the run at ISOLDE performed last August we completed the study of the decay properties of the $ 0 ^{+} _{2} $ level in $ ^{76, 78, 80}$Kr by measuring the lifetime of the $ 0 ^{+} _{2} $ level in $^{76}$Kr. This was done by applying the $\\beta \\gamma\\gamma$ (t) fast timing method to the $\\beta^{+} $-decay of $^{76}$Rb. For the first time the method was applied to proton-rich nuclei at ISOLDE. This required some special modifications of the experimental set-up previously used for the case of $\\beta^{-}$-decay due to the presence of intense annihilation radiation. The experiment has been successful and enough data have been collected for the determination of the lifetime. The analysis is in progress. From a very preliminary estimate it would appear that the lifetime value falls in the range 20-60 ps. Combining this value with the previously measured ratio \\[\\frac{B(E0; 0^{+}_{2} \\rightarrow 0^{+}_{1})}{B(E2; 0^{+}_{2} \\rightarrow 2^{+}_{1})}\\] It is possible to extract an estimate of the monopole transition...

  2. Indications of 2ν2K capture in 78Kr

    Science.gov (United States)

    Gavrilyuk, Yu. M.; Gangapshev, A. M.; Kazalov, V. V.; Kuzminov, V. V.; Panasenko, S. I.; Ratkevich, S. S.

    2013-03-01

    Results from searches of double K capture in 78Kr in an experiment with the large-volume copper proportional counter, using data samples corresponding of two independent series of measurements with different intrinsic radioactivity background are presented. The total exposure of the low-background measurements is 0.343 kg×y. A combination of methods of selection of useful events with a unique set of characteristics and wavelet analysis of events allowed a reduction of the background by ˜2000 times in the energy region of interest. The statistical significance of combined data from two stages of operation equals 2.5σ. Corresponding to such effect, the half-life of 78Kr relative to 2ν2K capture equals T1/2=[9.2-2.6+5.5(stat)±1.3(syst)]×1021 y. Half-life limits for other 2K transitions to the excited states in 78Se are obtained at the level of 1021 y in the first time. In particular, limits on 2ν2K capture to the excited level 01+ (1499 keV) and resonant neutrinoless double K capture to the level 2+ (2838 keV) have been defined on the level of T1/2≥5.4×1021 y at 90% C.L.

  3. Collisional metastability of high rotational states of CN(X 2Σ +, ? = 0)

    Science.gov (United States)

    Hay, S.; Shokoohi, F.; Callister, S.; Wittig, C.

    1985-07-01

    CN(X 2Σ +, v'' = 0) high rotational states relax slowly via 300 K collisions with Ar and Kr. Relaxation decreases with increasing rotation, and the partially relaxed distributions are bimodal, with low N'' thermalized (300 K), and N'' = 80 unrelaxed after 1000 collisions. Relaxation by N 2, CO, and Xe is similar to Ar and Kr, but more efficient. He and NO remove many quanta in a single collision.

  4. Analysis list: Ar [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Ar Gonad,Kidney,Prostate + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/targe...t/Ar.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Ar.5.tsv http://dbarchive.biosciencedbc.jp/...kyushu-u/mm9/target/Ar.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Ar.Gonad.tsv,http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/colo/Ar.Kidney.tsv,http://dbarchive.bioscienced...bc.jp/kyushu-u/mm9/colo/Ar.Prostate.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Gonad.gml,http://dbarchive.bioscience

  5. I-Xe Ages and the Thermal History of the Toluca IAB Meteorite

    Science.gov (United States)

    Pravdivtseva, O.; Meshik, A. P.; Petaev, M. I.; Hohenberg, C. M.

    2008-03-01

    The I-Xe system in Toluca silicates seems to survive catastrophic impact and breakup of the IAB parent body. As a result of cooling at about 40 +/- 20 K/Ma, the I-Xe system in the high-Mg pyroxenes in Toluca nodules closed at about 4559.7 Ma, in low-Mg pyroxenes at 4553.6-4548.9 Ma.

  6. Nuclear Spin Maser Oscillation of {sup 129}Xe by Means of Optical-Detection Feedback

    Energy Technology Data Exchange (ETDEWEB)

    Yoshimi, A., E-mail: yoshimi@rarfaxp.riken.jp; Asahi, K. [RIKEN (Japan); Emori, S.; Tsukui, M.; Oshima, S. [Tokyo Institute of Technology, Department of Physics (Japan)

    2004-12-15

    We have developed the nuclear spin maser oscillating at a low frequency of 34 Hz with highly polarized nuclear spins of the noble gas element {sup 129}Xe. The system is advantageous for detecting a small frequency shift of the nuclear spin precession. We are thus planning to apply this system to the search for an atomic electric dipole moment of {sup 129}Xe. We here report the development of the system and its performance.

  7. Basal Plane Fluorination of Graphene by XeF2 via a Radical Cation Mechanism.

    Science.gov (United States)

    Liu, Yijun; Noffke, Benjamin W; Qiao, Xiaoxiao; Li, Qiqi; Gao, Xinfeng; Raghavachari, Krishnan; Li, Liang-shi

    2015-09-17

    Graphene fluorination with XeF2 is an attractive method to introduce a nonzero bandgap to graphene under mild conditions for potential electro-optical applications. Herein, we use well-defined graphene nanostructures as a model system to study the reaction mechanism of graphene fluorination by XeF2. Our combined experimental and theoretical studies show that the reaction can proceed through a radical cation mechanism, leading to fluorination and sp(3)-hybridized carbon in the basal plane.

  8. Nuclear electric dipole moments for the lowest 1/2+ states in Xe and Ba isotopes

    Science.gov (United States)

    Yoshinaga, N.; Higashiyama, K.; Arai, R.; Teruya, E.

    2014-04-01

    The electric dipole moments for the lowest 1/2+ states of Xe and Ba isotopes are calculated in terms of the nuclear shell model, which includes two-body nucleon interactions violating parity and time-reversal invariance. Using the wave functions thus obtained, the nuclear electric dipole moments arising from the intrinsic nucleon electric dipole moments and also from asymmetric charge distribution are calculated. The upper limits for the nuclear electric dipole moments of Xe and Ba isotopes are estimated.

  9. Change of nuclear configurations in the neutrinoless double-$\\beta$ decay of $^{130}$Te $\\rightarrow$ $^{130}$Xe and $^{136}$Xe $\\rightarrow$ $^{136}$Ba

    CERN Document Server

    Entwisle, J P; Tamii, A; Adachi, S; Aoi, N; Clark, J A; Freeman, S J; Fujita, H; Fujita, Y; Furuno, T; Hashimoto, T; Hoffman, C R; Ideguchi, E; Ito, T; Iwamoto, C; Kawabata, T; Liu, B; Miura, M; Ong, H J; Schiffer, J P; Sharp, D K; Süsoy, G; Suzuki, T; Szwec, S V; Takaki, M; Tsumura, M; Yamamoto, T

    2016-01-01

    The change in the configuration of valence protons between the initial and final states in the neutrinoless double-$\\beta$ decay of $^{130}$Te $\\rightarrow$ $^{130}$Xe and of $^{136}$Xe $\\rightarrow$ $^{136}$Ba has been determined by measuring the cross sections of the ($d$,$^3$He) reaction with 101-MeV deuterons. Together with our recent determination of the relevant neutron configurations involved in the process, a quantitative comparison with the latest shell-model and interacting-boson-model calculations reveals significant discrepancies. These are the same calculations used to determine the nuclear matrix elements governing the rate of neutrinoless double-$\\beta$ decay in these systems.

  10. 40Ar/39Ar dating of Daqingshan thrust

    Institute of Scientific and Technical Information of China (English)

    LIU Zhenghong; XU Zhongyuan; YANG Zhensheng

    2003-01-01

    The Daqingshan thrust system, to the south of the Shiguai Mesozoic basin, is a complex system of top-to- the-north thrusting tectonic sheets. The thrust system has a complicated evolution due to multi-stage thrusting. In order to date the thrusting events, syntectonic muscovite and biotite grains are respectively analyzed with normal 40Ar/39Ar dating and laser 40Ar/39Ar dating, which yield 2 isochron ages, i.e. 193.74 ± 3.88 Ma and 121.6 ± 1.6 Ma. These ages suggest that faults within the Daqingshan thrust system formed during 2 stages of thrusting, one the early Indosinian and the other the late Yanshanian. The isotopic dating is consistent with field geological relations. Indosinan deformation is evidenced by top-to-the-north thrusting, with the occurrence of a series of large-scale east-west trending thrust faults and folds, while the Yanshanian thrusting is characterized by top-to-the-NNW thrusting. It is superposed on and modifies early Indosinian thrust faults.

  11. Methoprene-tolerant (Met) and Krüpple-homologue 1 (Kr-h1) are required for ovariole development and egg maturation in the brown plant hopper.

    Science.gov (United States)

    Lin, Xinda; Yao, Yun; Wang, Bo

    2015-12-14

    The brown plant hopper is one of the most destructive known pests of rice. We studied the roles of the JH receptor Met and the downstream transcription factor Kr-h1 in ovariole development and egg maturation. The predicted Met protein in N. lugens (NlMet) contained 517 amino acids. qRT-PCR showed that NlMet was expressed in all tissues and that the highest expression occurred in the embryonic stage. In NlMet- or NlKr-h1-silenced female adults, ovarian development varied significantly, whereas the numbers of ovarioles were less variable in those injected with dsRNA targeting NlMet, NlKrh-1 or both NlMet and NlKr-h1. In females injected with dsNlKr-h1 or with dsNlMet in combination with dsNlKr-h1 dsRNA, the preoviposition period was prolonged, whereas the females injected with NlMet dsRNA showed no significant changes. Moreover, we found no differences in the length of the preoviposition period between macropterous and brachypterous females. The disruption of Nlmet or NlKr-h1 or the dual knockdown of NlMet and NlKr-h1 significantly reduced the number of eggs laid. Moreover, significant differences were also found between the macropterous and the brachypterous brown plant hoppers. These results indicated that Met and Kr-h1 are required for ovariole development and egg maturation in the brown plant hopper.

  12. Molecular Characterization and Functional Analysis ofKrüppel-homolog 1 (Kr-h1) in the Brown Planthopper,Nilaparvata lugens (Stål)

    Institute of Scientific and Technical Information of China (English)

    JIN Min-na; XUE Jian; YAO Yun; LIN Xin-da

    2014-01-01

    The brown planthopper,Nilaparvata lugens (Stål), is the most serious insect pest of rice. It has developed high resistance to traditional insecticides because of their intensive use. Juvenile hormone (JH) analogs have been used successfully to control this species and other pest insects. However, the molecular mechanism of JH signaling is not well understood.Krüppel-homolog 1 (Kr-h1) is a transcription factor involved in the JH pathway. In this study, theKr-h1cDNA was cloned and characterized from N. lugens by rapid ampliifcation of cDNA ends (RACE) and reverse transcription PCR (RT-PCR). Its spatial and temporal expression proifles were examined by real-time quantitative PCR, and its function was also studied by RNA interference (RNAi). The open reading frame ofNlKr-h1 is 1833 bp encoding for 611 amino acids. The protein contains eight conserved zinc-ifnger motifs.NlKr-h1 was expressed at all life stages, with the highest mRNA level in the 4-day embryo.NlKr-h1 mRNA levels rose during each nymphal molt after the 2nd instar. In the adults, the mRNA level in males was signiifcantly higher than that in females of either the macropterous or brachypterous type. The highest expression was observed in the female midgut.NlKr-h1 was activated by juvenile hormone III (JH III) in the 3rd-5th instar nymphs. Disruption ofNlkr-h1expression by RNAi caused stunted wing development and malformations of both male and female external genitalia. Our ifndings suggest thatKr-h1may be a useful target for pest insect management.

  13. Probing confinement resonances by photoionizing Xe inside a C60+ molecular cage

    Science.gov (United States)

    Phaneuf, R. A.; Kilcoyne, A. L. D.; Aryal, N. B.; Baral, K. K.; Thomas, C. M.; Esteves-Macaluso, D. A.; Lomsadze, R.; Gorczyca, T. W.; Ballance, C. P.; Manson, S. T.; Hasoglu, M. F.; Hellhund, J.; Schippers, S.; Müller, A.

    2014-05-01

    Double photoionization accompanied by loss of n C atoms (n = 0 , 2 , 4 , 6) was investigated by merging beams of Xe@C60+ ions and synchrotron radiation and measuring the yields of product ions. The giant 4 d dipole resonance of the caged Xe atom has a prominent signature in the cross section for these product channels, which together account for 6 . 2 +/- 1 . 4 of the total Xe 4 d oscillator strength of 10. Compared to that for a free Xe atom, the oscillator strength is redistributed in photon energy due to multipath interference of outgoing Xe 4 d photoelectron waves that may be transmitted or reflected by the spherical C60+ molecular cage, yielding so-called confinement resonances. The data are compared with an earlier measurement and with theoretical predictions for this single-molecule photoelectron interferometer system. Relativistic R-matrix calculations for the Xe atom in a spherical potential shell representing the fullerene cage show the sensitivity of the interference pattern to the molecular geometry.

  14. Isomers and high-spin structures in the N =81 isotones 135Xe and 137Ba

    Science.gov (United States)

    Vogt, A.; Birkenbach, B.; Reiter, P.; Blazhev, A.; Siciliano, M.; Hadyńska-Klek, K.; Valiente-Dobón, J. J.; Wheldon, C.; Teruya, E.; Yoshinaga, N.; Arnswald, K.; Bazzacco, D.; Bowry, M.; Bracco, A.; Bruyneel, B.; Chakrawarthy, R. S.; Chapman, R.; Cline, D.; Corradi, L.; Crespi, F. C. L.; Cromaz, M.; de Angelis, G.; Eberth, J.; Fallon, P.; Farnea, E.; Fioretto, E.; Freeman, S. J.; Fu, B.; Gadea, A.; Geibel, K.; Gelletly, W.; Gengelbach, A.; Giaz, A.; Görgen, A.; Gottardo, A.; Hayes, A. B.; Hess, H.; Hirsch, R.; Hua, H.; John, P. R.; Jolie, J.; Jungclaus, A.; Kaya, L.; Korten, W.; Lee, I. Y.; Leoni, S.; Lewandowski, L.; Liang, X.; Lunardi, S.; Macchiavelli, A. O.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Müller-Gatermann, C.; Napoli, D.; Pearson, C. J.; Pellegri, L.; Podolyák, Zs.; Pollarolo, G.; Pullia, A.; Queiser, M.; Radeck, F.; Recchia, F.; Regan, P. H.; Rosiak, D.; Saed-Samii, N.; Şahin, E.; Scarlassara, F.; Schneiders, D.; Seidlitz, M.; Siebeck, B.; Sletten, G.; Smith, J. F.; Söderström, P.-A.; Stefanini, A. M.; Steinbach, T.; Stezowski, O.; Szilner, S.; Szpak, B.; Teng, R.; Ur, C.; Vandone, V.; Warner, D. D.; Wiens, A.; Wu, C. Y.; Zell, K. O.

    2017-02-01

    The high-spin structures and isomers of the N =81 isotones 135Xe and 137Ba are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in 136Xe+238U and (ii) 136Xe+208Pb MNT reactions employing the high-resolution Advanced Gamma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (iii) in the 136Xe+198Pt MNT reaction employing the γ -ray array GAMMASPHERE in combination with the gas-detector array CHICO, and (iv) via a 11B+130Te fusion-evaporation reaction with the HORUS γ -ray array at the University of Cologne. The high-spin level schemesof 135Xe and 137Ba are considerably extended to higher energies. The 2058-keV (19 /2-) state in 135Xe is identified as an isomer, closing a gap in the systematics along the N =81 isotones. Its half-life is measured to be 9.0(9) ns, corresponding to a reduced transition probability of B (E 2 ,19 /2-→15 /2-) =0.52 (6 ) W.u. The experimentally deduced reduced transition probabilities of the isomeric states are compared to shell-model predictions. Latest shell-model calculations reproduce the experimental findings generally well and provide guidance to the interpretation of the new levels.

  15. Experimental study of the astrophysical gamma-process reaction 124Xe(alpha,gamma)128Ba

    CERN Document Server

    Halász, Z; Gyürky, Gy; Elekes, Z; Fülöp, Zs; Szücs, T; Kiss, G G; Szegedi, N; Rauscher, T; Görres, J; Wiescher, M

    2016-01-01

    The synthesis of heavy, proton rich isotopes in the astrophysical gamma-process proceeds through photodisintegration reactions. For the improved understanding of the process, the rates of the involved nuclear reactions must be known. The reaction 128Ba(g,a)124Xe was found to affect the abundance of the p nucleus 124Xe. Since the stellar rate for this reaction cannot be determined by a measurement directly, the aim of the present work was to measure the cross section of the inverse 124Xe(a,g)128Ba reaction and to compare the results with statistical model predictions. Of great importance is the fact that data below the (a,n) threshold was obtained. Studying simultaneously the 124Xe(a,n)127Ba reaction channel at higher energy allowed to further identify the source of a discrepancy between data and prediction. The 124Xe + alpha cross sections were measured with the activation method using a thin window 124Xe gas cell. The studied energy range was between E = 11 and 15 MeV close above the astrophysically relevant...

  16. HP-Xe to go: Storage and transportation of hyperpolarized (129)Xenon.

    Science.gov (United States)

    Repetto, M; Zimmer, S; Allmendinger, F; Blümler, P; Doll, M; Grasdijk, J O; Heil, W; Jungmann, K; Karpuk, S; Krause, H-J; Offenhäusser, A; Schmidt, U; Sobolev, Y; Willmann, L

    2016-04-01

    Recently the spin-lattice relaxation time T1 of hyperpolarized (HP)-(129)Xe was significantly improved by using uncoated and Rb-free storage vessels of GE180 glass. For these cells, a simple procedure was established to obtain reproducible wall relaxation times of about 18 h. Then the limiting relaxation mechanism in pure Xe is due to the coupling between the nuclear spins and the angular momentum of the Xe-Xe van-der-Waals-molecules. This mechanism can be significantly reduced by using different buffer gases of which CO2 was discovered to be the most efficient so far. From these values, it was estimated that for a 1:1 mixture of HP-Xe with CO2 a longitudinal relaxation time of about 7 h can be expected, sufficient to transport HP-Xe from a production to a remote application site. This prediction was verified for such a mixture at a total pressure of about 1 bar in a 10 cm glass cell showing a storage time of T1≈9 h (for T1(wall)=(34±9) h) which was transported inside a magnetic box over a distance of about 200 km by car.

  17. KR-62980 suppresses lipid metabolism through inhibition of cytosolic NADP isocitrate dehydrogenase in zebrafish.

    Science.gov (United States)

    Chun, Hang-Suk; Shin, Sun Hye; Ahn, Sunjoo; Shin, Dae-Seop; Choi, Sun-Sil; Ahn, Jin Hee; Bae, Myung Ae

    2014-04-01

    Peroxisome proliferator-activated receptor γ (PPARγ) is a target of antidiabetic drugs. However, many PPARγ activators, including rosiglitazone, show unwanted side effects, such as weight gain. The KR-62980 [1-(trans-methylimino-N-oxy)-3-phenyl-6-(3-phenylpropoxy)-1H-indene-2-carboxylic acid ethyl ester], a novel partial agonist of PPARγ, is a new compound for diabetes with antihyperglycemic activity and weak antiadipogenic activity. This study was performed to elucidate the mechanism of the weak adipogenesis induced by KR-62980 despite its being a PPARγ agonist in zebrafish. We elucidated the mechanism of KR-62980 in lipid metabolism using adipocytes and zebrafish. Since NADPH is a critical cofactor in fat metabolism, we investigated effect of KR-62980 on NADPH-producing enzymes such as cytosolic NADP(+) isocitrate dehydrogenase (cICDH). We found that the mRNA expression of cICDH was significantly decreased by KR-62980 in 3T3-L1 cells. KR-62980 inhibited lipase activity and lipid metabolism in zebrafish. Further, KR-62980 substantially suppressed cICDH in adipocytes and zebrafish. These results suggest that cICDH may be one of the targets of KR-62980 responsible for weight gain and adipogenesis.

  18. Paulos Silentiarios' heksametre til genindvielsen af Hagia Sophia i 562 e.Kr

    DEFF Research Database (Denmark)

    Troelsgård, Christian; Christensen, Jonas

    2009-01-01

    Indledning, tekst og metrisk oversættelse af Paulos Silentiarios digt skrevet til Hagia Sophia-katedralens geninvielse i år 562 e.Kr. Udgivelsesdato: Maj 2009......Indledning, tekst og metrisk oversættelse af Paulos Silentiarios digt skrevet til Hagia Sophia-katedralens geninvielse i år 562 e.Kr. Udgivelsesdato: Maj 2009...

  19. Evaluering af "Organisering og Samspilsrelationer" Aalborg Kommunes projekt om Kræftrehabilitering

    DEFF Research Database (Denmark)

    Jespersen, Peter Kragh; Byg, Vibeke; Seemann, Janne

    2009-01-01

    Rapporten evaluerer et forsøg på tidlig indsats i kræftrehabilitering og vurderer de organisatoriske og ledelsesmæssige forhold i forsøget som involverer et samarbejde mellem kommune, Aalborg Sygehus og Kræftens Bekæmpelse...

  20. KR-62980: a novel peroxisome proliferator-activated receptor gamma agonist with weak adipogenic effects.

    Science.gov (United States)

    Kim, Kwang Rok; Lee, Jeong Hyung; Kim, Seung Jun; Rhee, Sang Dal; Jung, Won Hoon; Yang, Sung-Don; Kim, Sung Soo; Ahn, Jin Hee; Cheon, Hyae Gyeong

    2006-08-14

    The nuclear receptor peroxisome proliferator-activated receptor gamma (PPARgamma) is the target for the anti-diabetic drugs including thiazolidinediones. We report here the identification and characterization of a novel PPARgamma agonist KR-62980. KR-62980 acted as a selective PPARgamma agonist in transactivation assay with an EC50 of 15 nM. In fully differentiated 3T3-L1 adipocytes, KR-62980 induced [3H]-deoxyglucose uptake in a concentration-dependent manner in the presence of insulin. KR-62980 was weakly adipogenic with little induction of aP2 mRNA, and was able to antagonize the adipogenic effects of rosiglitazone in C3H10T1/2 cells. In vivo pharmacokinetic profile of KR-62980 revealed that the compound exhibited good oral bioavailability of 65% with a terminal elimination half-life of 2.5 h in the rat. Treatment of high fat diet-induced C57BL/6J mice with KR-62980 for 14 days reduced plasma glucose levels with little side effects with regard to weight gain, cardiac hypertrophy and hepatotoxicity. These results suggest that KR-62980 acts as a selective PPARgamma modulator with anti-hyperglycemic activity, and that the mechanism of actions of KR-62980 appears to be different from that of rosiglitazone with improved side effect profiles.

  1. Description of the shape coexistence in neutron-deficient 74,76Kr with IBM2

    Science.gov (United States)

    Zhang, DaLi; Mu, ChengFu

    2016-08-01

    The shape deformation and shape coexistence in 74,76Kr isotopes are investigated within the framework of the proton-neutron interacting boson model (IBM2). By considering the relative energy of the d proton boson to be different from that of the neutron boson, the low-lying energy spectrum is in good agreement with experimental results both qualitatively and quantitatively. In particular, the low-lying 0 2 + states associated with the shape-coexistence phenomenon are reproduced quite well. The calculated key sensitive quantities of B(E2) transition branch ratios are fairly consistent with the experimental data except for R 4. The predicated deformation parameter is very similar for the ground states in 74Kr and 76Kr, showing good agreement with the experimental result, and the calculated deformation parameter for the second 0+ state in 74Kr is close to the experimental data. The calculated results of the triaxiality parameter indicated an almost purely prolate shape for the ground state of 76Kr and a mostly prolate shape with a little triaxiality for the ground state of 74Kr. The calculations also show an oblate triaxial shape for the second 0+ state in 76Kr and maximum triaxiality for the second 0+ state in 74Kr. These results confirm the importance of the triaxial deformation for the description of such shape coexistence.

  2. Stellar laboratories . VIII. New Zr iv-vii, Xe iv-v, and Xe vii oscillator strengths and the Al, Zr, and Xe abundances in the hot white dwarfs G191-B2B and RE 0503-289

    Science.gov (United States)

    Rauch, T.; Gamrath, S.; Quinet, P.; Löbling, L.; Hoyer, D.; Werner, K.; Kruk, J. W.; Demleitner, M.

    2017-03-01

    Context. For the spectral analysis of high-resolution and high-signal-to-noise spectra of hot stars, state-of-the-art non-local thermodynamic equilibrium (NLTE) model atmospheres are mandatory. These are strongly dependent on the reliability of the atomic data that is used for their calculation. Aims: To search for zirconium and xenon lines in the ultraviolet (UV) spectra of G191-B2B and RE 0503-289, new Zr iv-vii, Xe iv-v, and Xe vii oscillator strengths were calculated. This allows, for the first time, determination of the Zr abundance in white dwarf (WD) stars and improvement of the Xe abundance determinations. Methods: We calculated Zr iv-vii, Xe iv-v, and Xe vii oscillator strengths to consider radiative and collisional bound-bound transitions of Zr and Xe in our NLTE stellar-atmosphere models for the analysis of their lines exhibited in UV observations of the hot WDs G191-B2B and RE 0503-289. Results: We identified one new Zr iv, 14 new Zr v, and ten new Zr vi lines in the spectrum of RE 0503-289. Zr was detected for the first time in a WD. We measured a Zr abundance of -3.5 ± 0.2 (logarithmic mass fraction, approx. 11 500 times solar). We identified five new Xe vi lines and determined a Xe abundance of -3.9 ± 0.2 (approx. 7500 times solar). We determined a preliminary photospheric Al abundance of -4.3 ± 0.2 (solar) in RE 0503-289. In the spectra of G191-B2B, no Zr line was identified. The strongest Zr iv line (1598.948 Å) in our model gave an upper limit of -5.6 ± 0.3 (approx. 100 times solar). No Xe line was identified in the UV spectrum of G191-B2B and we confirmed the previously determined upper limit of -6.8 ± 0.3 (ten times solar). Conclusions: Precise measurements and calculations of atomic data are a prerequisite for advanced NLTE stellar-atmosphere modeling. Observed Zr iv-vi and Xe vi-vii line profiles in the UV spectrum of RE 0503-289 were simultaneously well reproduced with our newly calculated oscillator strengths. Based on observations

  3. Analytical method of Kr-85 determination, using cryogenic concentration and separation and liquid scintillation counting; Desarrollo del metodo de concentracion y se paracion criogenica cromatografica y medida radiactiva por centelleo liquido de Kr-85

    Energy Technology Data Exchange (ETDEWEB)

    Heras, M. C.; Perez, M. M.; Grau, A.

    1983-07-01

    The method used in the Laboratory of the JEN for the determination of Kr-85 levels in gaseous effluents of nuclear power and in the atmosphere is described. Samples of air, collected in metallic cylinders, are introduced into a gas-solid chromatographic separation system which resolves Kr from the other air components. The separated Kr ia dissolved in a toluene based scintillation cocktail, and the Kr-85 content is determined by liquid scintillation counting. (Author)

  4. Development and selection of a matrix alloy for /sup 85/Kr encapsulation

    Energy Technology Data Exchange (ETDEWEB)

    Knoll, R.W.; McClanahan, E.D.; Tingey, G.L.; McDonald, E.L.

    1986-07-01

    Pacific Northwest Laboratory has developed and demonstrated a pilot-scale process for stable, long-term storage of radioactive /sup 85/Kr gas from spent nuclear fuel. The process entraps the Kr into a solid metal matrix that can be safely stored at ambient pressure. For this matrix numerous alloys were first screened; those that best satisfied the selection criteria were Cu-Y, Ni-Y, and Ni-La. Of these, Cu-Y alloys containing approximately 20 at.% Y were recommended for use in the pilot-scale system. Reasons for this decision, based on the development work described in Section 5, are summarized here. Thick Cu-Y-Kr deposits (greater than or equal to1 mm) exhibit much better thermal and mechanical stability than do those of Ni-La-Kr and are at least as stable as Ni-Y-Kr deposits. Cu-Y-Kr coatings are very compatible with the sputtering process. They adhere well to the substrate, do not spall significantly during deposition, and can be deposited at higher rates than the Ni-base alloys. This faster deposition helps compensate, in terms of process efficiency, for the lower Kr capacity of Cu-Y-Kr alloys. Another advantage of Cu-Y over Ni-base alloys is the higher vapor pressure of Cu compared to Ni. This reduces the unwanted buildup of Cu on the hot anode surface, whereas deposition of Ni is a problem with Ni-Y, for example. Cu-Y-Kr deposits containing 17 to 20 at. % Y and 6 to 8 at. % Kr compared favorably to Ni/sub 80/La/sub 10/Kr/sub 10/ in terms of long-term Kr retention characteristics. The measurements of Cu-Y-Kr by differential scanning calorimetry also indicated stable retention of Kr because rapid release did not occur below approx.650/sup 0/C. Finally, Cu-Y alloys are satisfactory in terms of materials costs and producibility of the sputtering target. 13 refs., 9 figs., 4 tabs.

  5. Mass measurement on the rp-process waiting point {sup 72}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, D.; Beck, D.; Herfurth, F.; Kluge, H.-J. [GSI, Darmstadt (Germany); Kolhinen, V.S.; Aeystoe, J.; Jokinen, A. [University of Jyvaeskylae, Jyvaeskylae (Finland); Audi, G. [CSNSM-IN2P3-CNRS, Orsay-Campus (France); Blaum, K. [GSI, Darmstadt (Germany); University of Mainz, Institute of Physics, Mainz (Germany); Bollen, G.; Schwarz, S. [Michigan State University, NSCL, East Lansing, MI (United States); Kellerbauer, A.; Sauvan, E. [CERN, Physics Department, Geneva (Switzerland); Oinonen, M. [University of Helsinki, Helsinki Institute of Physics, Helsinki (Finland); Schatz, H. [Michigan State University, NSCL, East Lansing, MI (United States); Michigan State University, Joint Institute for Nuclear Astrophysics, East Lansing, MI (United States)

    2005-09-01

    With the aim of improving nucleosynthesis calculations, we performed for the first time, a direct high-precision mass measurement on the waiting point in the astrophysical rp-process {sup 72}Kr. We used the ISOLTRAP Penning trap mass spectrometer located at ISOLDE/CERN. The measurement yielded a relative mass uncertainty of {delta}m/m=1.2 x 10{sup -7}. In addition, the masses of {sup 73}Kr and {sup 74}Kr were measured directly with relative mass uncertainties of 1.0 x 10{sup -7} and 3 x 10{sup -8}, respectively. We analyzed the role of {sup 72}Kr in the rp-process during X-ray bursts using the ISOLTRAP and previous mass values of {sup 72-74}Kr. (orig.)

  6. High-spin {gamma}-ray spectroscopy of {sup 124}Ba, {sup 124}Xe and {sup 125}Xe

    Energy Technology Data Exchange (ETDEWEB)

    Al-Khatib, Ali

    2008-08-18

    rotational bands loose collectivity and, finally, when all nucleons outside the core have their spins aligned, the bands terminate. In the framework of this thesis, extensive spectroscopic investigations of three nuclei of the A {proportional_to}125 region, {sup 124}Ba, {sup 124}Xe and {sup 125}Xe, have been performed. These nuclei have been studied with the largest spectrometers available, Euroball and Gammasphere. The previously known level schemes of these nuclei have been extended substantially, both in the low- and high-spin regions. Many new rotational bands could be established. Lifetimes have been measured for several of the long large-deformation bands. The rotational structures, shape co-existence and band termination at high spins have been investigated. (orig.)

  7. AR DOC: Augmented reality documentaries

    DEFF Research Database (Denmark)

    Vistisen, Peter

    2014-01-01

    Augmented Reality Documentaries (AR DOC) er et ’lille’ Shareplay projekt (ansøgte midler augmented reality cross media løsninger, til at skabe engagerende publikumsformidling...... indenfor oplevelsesindustrien. Projektet har genereret ny viden omkring, hvordan fysisk og digital formidling kan understøttes via Augmented Reality som formidlingsformat....

  8. "Ars Electronica 2009" / Raivo Kelomees

    Index Scriptorium Estoniae

    Kelomees, Raivo, 1960-

    2009-01-01

    30. "Ars Electronica" festival "Human Nature" ("Inimese loomus") Linzis. Osaka ülikooli professori Hiroshi Ishiguro mehaanilis-digitaalsest nukust. Hübriidkunsti kategoorias peapreemia saanud Eduardo Kaci inimtaimest. Konverentsidest. Näitusest "See this Sound", mis oli pühendatud helile kujutavas kunstis

  9. Reactivity of Xe with ice at extreme P-T conditions

    Science.gov (United States)

    Sanloup, C.; Hochlaf, M.; Maynard-Casely, H.; Gregoryanz, E.; Mezouar, M.

    2010-12-01

    Water is an important component of terrestrial and giant planets so that any reactivity with Xe at depth would have strong consequences on our knowledge of planetary dynamics as it heavily relies on Xe isotopes geochemistry. The chemistry of ‘noble gas’ have seen fascinating experimental and theoretical advances during the last twenty years as highlighted by review papers (1,2). Noble gas chemistry proceeds essentially by photosynthesis of precursors in a low-temperature noble-gas matrix. The pressure variable has seldom been investigated as a mean to enforce Xe to bond other elements (3). Xe is among the gases that stabilize clathrate hydrates through van der Waals interactions. Xe hydrates are stable up to 2.5 GPa, before dissociating into Xe plus ice VII (4). However, the chemistry of water with solid Xe has been successfully explored by UV photolysis (5,6). Those findings plus our own results on the stability of Xe oxides in the terrestrial crust (7) let us envisage that the chemistry of Xe with oxygen at extreme conditions could be flourishing. We have thus explored the reactivity of Xe with water up to 80 GPa by using a laser-heated diamond-anvil cell combined with in situ x-ray diffraction measurements. Formation of a compound is indeed observed at conditions that could occur in the interiors of ice-rich giant planets Uranus and Neptune. To complement the x-ray diffraction data, ab initio calculations have been carried out to determine the molecular structure of the new found compound. These resuts hence add another example of noble gas sequestration in giant planets, as recently proposed for Ne (8). References: 1. W. Grochala, Chem. Soc. Rev. 1632, 36 (2007). 2. R. B. Gerber, Annu. Rev. Phys. Chem., 55, 55 (2004). 3. A. I. Katz and V. A. Apkarian, J. Phys. Chem., 94, 6671-6678 (1990). 4. C. Sanloup et al., PNAS 99, 25 (2002). 5. M. Pettersson et al., Eur. J. Inorg. Chem. 505, 729 (1999). 6. L. Khriachtchev et al., JACS 130, 6114 (2008). 7. C. Sanloup et

  10. Enzyme kinetic study of a new cardioprotective agent, KR-32570 using human liver microsomes and recombinant CYP isoforms.

    Science.gov (United States)

    Kim, Hyojin; Seo, Kyung-Ah; Kim, Hyunmi; Lee, Hye Suk; Lee, Choong-Hwan; Shin, Jae-Gook; Liu, Kwang-Hyeon

    2007-04-01

    KR-32570 (5-(2-Methoxy-5-chlorophenyl)furan-2-ylcarbonyl)guanidine) is a new cardioprotective agent for preventing ischemia-reperfusion injury. Human liver microsomal incubation of KR-32570 in the presence of NADPH resulted in the formation of two metabolites, hydroxy-KR-32570 and O-desmethyl-KR-32570. In this study, a kinetic analysis of the metabolism of two metabolites from KR-32570 was performed in human liver microsomes, and recombinant CYP1A2, and CYP3A4. The metabolism for hydroxy- and O-desmethyl-KR-32570 formation from KR-32570 by human liver microsomes was best described by a Michaelis-Menten equation and a Hill equation, respectively. The Cl(int) values of hydroxy- and O-desmethyl-KR-32570 formation were similar to each other (0.03 vs 0.04 microL/min/pmol CYP, respectively). CYP3A4 mediated the formation of hydroxy-KR-32570 from KR-32570 with Cl(int) = 0.24 microL/min/pmol CYP3A4. The intrinsic clearance for O-desmethyl-KR-32570 formation by CYP1A2 was 0.83 AL/min/pmol CYP1A2. These findings suggest that CYP3A4 and CYP1A2 enzymes are major enzymes contributing to the metabolism of KR-32570.

  11. Experimental verification of a zero-dimensional model of the kinetics of XeCl* discharges by Xe*-, Cl*-, Ne*-, and H*-density measurements

    Energy Technology Data Exchange (ETDEWEB)

    Schwabedissen, A. (Inst. fuer Plasmaphysik, Univ. Hannover (Germany)); Loffhagen, D. (Inst. fuer Plasmaphysik, Univ. Hannover (Germany)); Boetticher, W. (Inst. fuer Plasmaphysik, Univ. Hannover (Germany)); Hammer, T. (Siemens AG, Corp. Research and Development, Plasma and Switching Technology, Erlangen (Germany))

    1994-06-01

    Absorption spectroscopic measurements of effective particle number densities of excited Xe, Ne, Cl, and H performed on a small scale discharge with well-defined current and voltage pulses are compared with the results of model calculations over a wide range of discharge parameters. The reaction kinetic pathways determining the ionization and dissociative attachment rates have been verified by the good agreement obtained during the quasi-steady-state phase of the discharge for Xe and H. To reproduce the rise times of the excited Xe particle number densities during the ignition phase, the electron collision excitation cross sections of ground state Xe published by Puech and Mizzi had to be enhanced by about 25%. From the Ne measurements it is concluded that the electron collision excitation cross sections of ground state Ne published by Puech and Mizzi may be too large near the theshold. Measurements of excited Cl particle number densities re unsuitable to check the attachment kinetics of HCl, because these densities are mainly determined by reactions not involving the formation of Cl[sup -] ions. (orig.)

  12. Experimental verification of a zero-dimensional model of the kinetics of XeCl* discharges by Xe*-, Cl*-, Ne*-, and H*-density measurements

    Science.gov (United States)

    Schwabedissen, A.; Loffhagen, D.; Hammer, Th.; Bötticher, W.

    1994-06-01

    Absorption spectroscopic measurements of effective particle number densities of excited Xe, Ne, Cl, and H performed on a small scale discharge with well-defined current and voltage pulses are compared with the results of model calculations over a wide range of discharge parameters. The reaction kinetic pathways determining the ionization and dissociative attachment rates have been verified by the good agreement obtained during the quasi-steady-state phase of the discharge for Xe and H. To reproduce the rise times of the excited Xe particle number densities during the ignition phase, the electron collision excitation cross sections of ground state Xe published by Puech and Mizzi [1] had to be enhanced by about 25%. From the Ne measurements it is concluded that the electron collision excitation cross sections of ground state Ne published by Puech and Mizzi [1] may be too large near the threshold. Measurements of excited Cl particle number densities are unsuitable to check the attachment kinetics of HCl, because these densities are mainly determined by reactions not involving the formation of Cl- ions.

  13. Xe-135 and Sm-149 Isotopic Evolution Analysis Xesamo code; Analisis de la Evolucion Isotopica del Xe-135 y Sm-149. Programa Xesamo

    Energy Technology Data Exchange (ETDEWEB)

    Caro, R.; Gallego, J.; Martinez Fanegas, R.

    1977-07-01

    In this report the time evolution analysis of the nuclides concentration Xe-135 and Sm-149 as a function of the neutron flux is carried out. The neutron flux may be any function of time. It is analyzed as well the reactivity changes associated with the xenon and samarium concentration variations. (Author) 5 refs.

  14. Multiphoton processes in KrF-laser induced gas breakdown

    Energy Technology Data Exchange (ETDEWEB)

    Poprawe, R.; Herziger, G.

    1986-05-01

    Ionization by multiphoton processes is the dominant generation mechanism of first electrons in the UV-laser-induced gas breakdown. A strongly simplified analytical model for the ion generation rate is used to give an estimate of the threshold intensity I/sub TH/. The result is compared to descriptions by Keldish and Bebb to check its limits of applicability. Solving the kinetic conservation equations for the focus volume gives an estimation of the breakdown intensity where the Debye criterion has been used in the sense of a plasma definition. As an example, breakdown experiments with a KrF-escimer laser have been carried out at different pressures in an argon atmosphere. The pressure dependency of the breakdown threshold intensity and its order of magnitude are predicted by the model.

  15. New atomic data for Kr XXXV useful in fusion plasma

    Institute of Scientific and Technical Information of China (English)

    Sunny Aggarwal; Jagjit Singh; Man Mohan

    2013-01-01

    Energy levels and emission line wavelengths of high-Z materials are useful for impurity diagnostics due to their potential application in the next generation fusion devices.For this purpose,we have calculated the fine structural energies of the 67 levels belonging to the ls2,ls21,ls31,ls41,ls51,and ls61 configurations of Kr XXXV using GRASP (general purpose relativistic atomic structure package) code.Additionally,we have reported the transition probabilities,oscillator strengths,line strengths,and transition wavelengths for some electric dipole (El) transitions among these levels.We predict new energy levels and radiative rates,which have not been reported experimentally or theoretically,forming the basis for future experimental work.

  16. String Theory on Elliptic Curve Orientifolds and KR-Theory

    Science.gov (United States)

    Doran, Charles; Méndez-Diez, Stefan; Rosenberg, Jonathan

    2015-04-01

    We analyze the brane content and charges in all of the orientifold string theories on space-times of the form , where E is an elliptic curve with holomorphic or anti-holomorphic involution. Many of these theories involve "twistings" coming from the B-field and/or sign choices on the orientifold planes. A description of these theories from the point of view of algebraic geometry, using the Legendre normal form, naturally divides them into three groupings. The physical theories within each grouping are related to one another via sequences of T-dualities. Our approach agrees with both previous topological calculations of twisted KR-theory and known physics arguments, and explains how the twistings originate from both a mathematical and a physical perspective.

  17. Armenian Astronomical Society (ArAS) activities

    Science.gov (United States)

    Mickaelian, A. M.

    2016-09-01

    A review on the activities and achievements of Armenian Astronomical Society (ArAS) and Armenian astronomy in general during the last years is given. ArAS membership, ArAS electronic newsletters (ArASNews), ArAS webpage, Annual Meetings, Annual Prize for Young Astronomers (Yervant Terzian Prize) and other awards, international relations, presence in international organizations, local and international summer schools, science camps, astronomical Olympiads and other events, matters related to astronomical education, astronomical heritage, amateur astronomy, astronomy outreach and ArAS further projects are described and discussed.

  18. Hydraulic conductivity measurements with HTU at Eurajoki, Olkiluoto, drillholes OL-KR52 and OL-KR47 in 2013 and 2014

    Energy Technology Data Exchange (ETDEWEB)

    Hurmerinta, E. [Poeyry Finland Oy, Vantaa (Finland)

    2014-09-15

    As a part of the site investigations for the disposal of spent nuclear fuel, hydraulic conductivity measurements were carried out with the HTU-equipment in drillholes OL KR52 and OL KR47 on the Olkiluoto investigation site. The objective was to investigate the distribution of the hydraulic conductivity in the surrounding bedrock volume. In OL-KR52 measurements were carried out between February 2013 and April 2013 and in OL-KR47 between October 2013 and February 2014. The total length of the drillhole OL-KR52 is 427.35 m, 376.00 m of which was covered by 188 standard tests with 2 m packer separation as specified in the measurement plan. Respectively, OL-KR47 is 1008.76 m long and 312 similar tests were conducted in it covering 624.00 m of the drillhole. These numbers include one equipment test measurement near the surface in OL-KR47. Double-packer constant-head method was used throughout with nominal 200 kPa overpressure. Injection stage lasted normally 20 minutes and fall-off stage 10 minutes. The tests were often shortened if there were clear indications that the hydraulic conductivity is below the measuring range of the system. The pressure in the test section was let to stabilise at least 5 min before injection. In some test sections the test stage times were extended if longer times were needed to obtain correct results or when suited to the working schedule. Two transient (Horner and 1/Q) interpretations and one stationary-state (Moye) interpretation were made in-situ immediately after the test. The Hydraulic Testing Unit (HTU-system) is owned by Posiva Oy and it was operated by Poeyry Finland Oy in co-operation with Geopros Oy. (orig.)

  19. Measurement of picosecond lifetimes in neutron-rich Xe isotopes

    Science.gov (United States)

    Ilieva, S.; Kröll, Th.; Régis, J.-M.; Saed-Samii, N.; Blanc, A.; Bruce, A. M.; Fraile, L. M.; de France, G.; Hartig, A.-L.; Henrich, C.; Ignatov, A.; Jentschel, M.; Jolie, J.; Korten, W.; Köster, U.; Lalkovski, S.; Lozeva, R.; Mach, H.; Mǎrginean, N.; Mutti, P.; Paziy, V.; Regan, P. H.; Simpson, G. S.; Soldner, T.; Thürauf, M.; Ur, C. A.; Urban, W.; Warr, N.

    2016-09-01

    Background: Lifetimes of nuclear excited states in fission fragments have been studied in the past following isotope separation, thus giving access mainly to the fragments' daughters and only to long-lived isomeric states in the primary fragments. For the first time now, short-lived excited states in the primary fragments, produced in neutron-induced prompt fission of 235U and 241Pu, were studied within the EXILL&FATIMA campaign at the intense neutron-beam facility of the Institute Laue-Langevin in Grenoble. Purpose: We aim to investigate the quadrupole collective properties of neutron-rich even-even 138,140,142Xe isotopes lying between the double shell closure N =82 and Z =50 and a deformed region with octupole collectivity. Method: The γ rays emitted from the excited fragments were detected with a mixed array consisting of 8 HPGe EXOGAM Clover detectors (EXILL) and 16 LaBr3(Ce) fast scintillators (FATIMA). The detector system has the unique ability to select the interesting fragment making use of the high resolution of the HPGe detectors and determine subnanosecond lifetimes using the fast scintillators. For the analysis the generalized centroid difference method was used. Results: We show that quadrupole collectivity increases smoothly with increasing neutron number above the closed N =82 neutron shell. Our measurements are complemented by state-of-the-art theory calculations based on shell-model descriptions. Conclusions: The observed smooth increase in quadrupole collectivity is similar to the evolution seen in the measured masses of the xenon isotopic chain and is well reproduced by theory. This behavior is in contrast to higher Z even-even nuclei where abrupt change in deformation occurs around N =90 .

  20. Hunting for the Carrier of a New Xe Component (H-C(sub)delta Xe) in Diamond-rich Residues of Primitive Meteorites

    Science.gov (United States)

    Verchovsky, A. B.; Russell, S. S.; Pillinger, C. T.; Fisenko, A. V.; Shukolyukov, Yu. A.

    1992-07-01

    Noble gases released at high temperature during both stepped pyrolysis and combustion of diamond-rich residues separated from some primitive meteorites (CV3s-Allende, Efremovka; LL3.4-Inman) contain Xe with isotopic composition different from HL-, Sol-, Pl- and S-Xe or their mix (Lewis and Anders, 1988; Nichols et al., 1991; Verchovsky et al., 1992). The regular recognition of the new Xe component or subcomponent requires it be given a name; we suggest to call it high-temperature Cdelta xenon or H-Cdelta Xe. At present only few characteristic features of the component and its possible host phase can be pointed out: Firstly, its occurrence only in association with what are believed to be very pure diamond separates hosting Xe-HL, characterised by ^136Xe/^132Xe >0.6, means that the carrier of the H-Cdelta Xe is very resistant to oxidising acids. Secondly, release of the H-Cdelta Xe in the range 600-800 degrees C in combustion experiments (Verchovsky et al., 1992) and at T > 1300 degrees C in pyrolysis experiments (Lewis and Anders, 1988; Nichols et al., 1991) suggests a host phase that is more resistant to pure oxygen and retentive with respect to the release of noble gases by diffusion than nanometer sized diamonds. It should be noted that stepped combustion provides significantly better resolution of the noble gas components than stepped pyrolysis and particularly at high temperature where for the former there is a large temperature gap between the end of Cdelta diamond combustion (~500 degrees C) and the majority SiC burning (~1000 degrees C); during pyrolysis the evolution of Xe-HL and Xe-S frequently overlap. Thirdly, the H-Cdelta Xe is accompanied by other noble gases in particular by Ne with ^20Ne/^22Ne lower than in NeA2 (Verchovsky et al., 1992). Based on these observations the H-Cdelta Xe and the associated noble gases are likely to be of presolar origin and their carrier appears to be a carbon phase. Indeed all the residues from the meteorites listed above

  1. New method of 85Kr reduction in a noble gas based low-background detector

    CERN Document Server

    Akimov, D Yu; Burenkov, A A; Hall, C; Kovalenko, A G; Kuzminov, V V; Simakov, G E

    2016-01-01

    Krypton-85 is an anthropogenic beta-decaying isotope which produces low energy backgrounds in dark matter and neutrino experiments, especially those based upon liquid xenon. Several technologies have been developed to reduce the Kr concentration in such experiments. We propose to augment those separation technologies by first adding to the xenon an 85Kr-free sample of krypton in an amount much larger than the natural krypton that is already present. After the purification system reduces the total Kr concentration to the same level, the final 85Kr concentration will have been reduced even further by the dilution factor. A test cell for measurement of the activity of various Kr samples has been assembled, and the activity of 25-year-old Krypton has been measured. The measured activity agrees well with the expected activity accounting for the 85Kr abundance of the earth atmosphere in 1990 and the half-life of the isotope. Additional tests with a Kr sample produced in the year 1944 (before the atomic era) have be...

  2. Neuroprotective effect of KR-31378 via KATP channel opening against ischemic insult.

    Science.gov (United States)

    Won, Ran; Lim, Jong-Yoon; Lee, Sang-Yeon; Park, Ji-Ho; Sohn, Nak-Won

    2004-08-01

    The opening of the adenosine triphosphate (ATP)-sensitive potassium (KATP) channel has been proposed as a therapeutic approach for ischemia. Here we examined the opening effect of KR-31378 on the KATP channel using patch clamp recording in neuroblastoma 2a (N2a) cells and investigated the neuroprotective effect of KR-31378 in organotypic hippocampal slice cultures exposed to oxygen/glucose deprivation. The treatment with KR-31378 (10 microM) to N2a cells seemed to induce KATP channel opening in a dose dependent manner. The opening effect of KR-31378 was more significant than that of other known KATP channel openers. Pretreatment with KR-31378 (10 microM) showed a neuroprotective effect in both CA1 and CA3 regions and its effect was attenuated by glibenclamide in a dose dependent manner in both areas. This remarkable neuroprotective effect of KR-31378 seemed to be mediated by the opening of the KATP channel. These results suggest that KR-31378 could be a possible neuroprotective agent against cerebral ischemia.

  3. ar

    Directory of Open Access Journals (Sweden)

    P. Fanlo

    Full Text Available A pesar de que el pulmón es el órgano diana por excelencia de la tuberculosis, cualquier otro órgano y sistema puede verse afectado. En este trabajo se revisan las formas de tuberculosis extrapulmonar a excepción de la pleural que requieren del facultativo, en ocasiones, su más valiosa pericia diagnóstica. Desde la temida meningitis tuberculosa, pasando por la afectación insidiosa de la espondilodiscitis, la llamativa afectación ganglionar, la afectación genitourinaria, la pericarditis, para terminar las formas menos frecuentes como la ocular o la cutánea. En cada apartado indicaremos lo más característico con la finalidad de que pueda servir de orientación diagnóstica y terapéutica.

  4. 西藏邦铺钼铜矿区He、Ne和Ar同位素及成矿流体示踪%He, Ne and Ar Isotopic Composition and Origin of Ore-forming Fluids of Bangpu Mo-Cu Mine Area, Tibet

    Institute of Scientific and Technical Information of China (English)

    温泉; 温春齐; 霍艳; 周雄; 费光春; 黄于鉴

    2012-01-01

    Bangpu Cu—Mo ore area is located in the east oi the Gangdisi porphyry copper zone in Tibet. It is a typical copper-molybdenum metal ore deposit with large type porphyry. Noble gas isotopes in the fluid inclusions in the molybdenite of Mo-Cu ore body and in the pyrite of Pb-Zn ore body were tested. The results show that the contents of 4He, 20Ne, 40Ar, 34Kr and 132Xe in the fluid inclusions of the molybdenite in Mo-Cu ore body are higher than these of the pyrite in Pb-Zn ore body. The partial ratio in the former is lower than that in the latter, such as 3He/4He is 0.347 and 5.80, 21Ne/22Ne is 0.027 2 and 0.045 8, 40Ar/36Ar is 381.9 and 743.3, respectively. It shows that the fluid of the deposit may belong to crust-mantle mixed source, the fluid source of molybdenite maybe come from the crust-derived fluid or atmospheric water, pyrite fluid source mayhe come from mantle -derived fluid. This result is consistent with the investigation of the quartz fluid inclusions of hydrogen and oxygen isotopes.%邦铺钼铜多金属矿区位于西藏冈底斯斑岩铜矿带东段,是典型的大型斑岩型钼铜多金属矿床.对该矿床钼铜矿体和铅锌矿体的辉钼矿和黄铁矿流体包裹体进行了稀有气体同位素测试.测试显示,辉钼矿流体包裹体中4He,20Ne,40Ar,84Kr和132Xe含量均高于铅锌矿体的黄铁矿;但部分比值前者却低于后者,3He/4He分别为0.347和5.80,21Ne/22Ne分别为0.0272和0.0458,40Ar/36Ar分别为381.9和743.3.研究认为,该矿床流体可能属壳幔混源,辉钼矿流体来源以壳源流体或大气水为主,黄铁矿流体来源以幔源流体为主.这与石英矿物流体包裹体氢氧同位素研究一致.

  5. Enhanced KR-Fundamental Measure Functional for Inhomogeneous Binary and Ternary Hard Sphere Mixtures

    Institute of Scientific and Technical Information of China (English)

    ZHOU Shi-Qi

    2011-01-01

    An enhanced KR-fundarnentai measure functional (FMF) is elaborated and employed to investigate binary and ternary hard sphere fluids near a planar hard wall or confined within two planar hard wails separated by certain interval.The present enhanced KR-FMF incorporates respectively, for aim of comparison, a recent 3rd-order expansion equation of state (EOS) and a Boublik's extension of Kolafa's EOS for HS mixtures.It is indicated that the two versions of the EOS lead to, in the framework of the enhanced KR-FMF, similar density profiles, but the 3rd-order EOS is more consistent with an exact scaled particle theory (SPT) relation than the BK EOS.Extensive comparison between the enhanced KR-FMF-3rd-order EOS predictions and corresponding density profiles produced in different periods indicates the excellent performance of the present enhanced KR-FMF-3rd-order EOS in comparison with other available density functional approximations (DFAs).There are two anomalous situations from whose density profiles all DFAs studied deviate significantly; however, subsequent new computer simulation results for state conditions similar to the two anomalous situations are in very excellent agreement with the present enhanced KR-FMF-3rd-order EOS.The present paper indicates that (i) the validity of the “naive” substitution elaborated in the present paper and peculiar to the original KR-FMF is still in operation even if inhomogeneous mixtures are being dealt with; (ii) the high accuracy and seff-consistency of the third order EOS seem to allow for application of the KR-FMF-third order EOS to more severe state conditions; and (iii) the “naive” substitution enables very easy the combination of the original KR-FMF with future's more accurate but potentially more complicated EOS of hard sphere mixtures.

  6. Novel synthetic protective compound, KR-22335, against cisplatin-induced auditory cell death.

    Science.gov (United States)

    Shin, Yoo Seob; Song, Suk Jin; Kang, Sungun; Hwang, Hye Sook; Jung, Young-Sik; Kim, Chul-Ho

    2014-02-01

    Cisplatin [cis-diammine-dichloroplatinum (II)] is a widely used chemotherapeutic agent, and one of its most severe side effects is ototoxicity. In the course of developing a new protective agent against cisplatin-induced ototoxicity, we have been interested in a novel synthetic compound, 3-Amino-3-(4-fluoro-phenyl)-1H-quinoline-2,4-dione (KR-22335). We evaluated the effectiveness of KR-22335 as an otoprotective agent against cisplatin-induced toxicity. The otoprotective effect of KR-22335 against cisplatin was tested in vitro in cochlear organs of Corti-derived cell lines, HEI-OC1, and in vivo in a zebrafish (Danio rerio) model. Cisplatin-induced apoptosis, cell cycle arrest and an increase in intracellular reactive oxygen species (ROS) generation were demonstrated in HEI-OC1 cells. KR-22335 inhibited cisplatin-induced apoptosis and mitochondrial injury in HEI-OC1 cells. KR-22335 inhibited cisplatin-induced activation of JNK, p-38, caspase-3 and PARP in HEI-OC1 cells. Scanning and transmission electron micrographs showed that KR-22335 prevented cisplatin-induced destruction of kinocilium and stereocilia in zebrafish neuromasts. Tissue TUNEL of neuromasts in zebrafish demonstrated that KR-22335 blocked cisplatin-induced TUNEL positive hair cells in neuromasts. The results of this study suggest that KR-22335 may prevent ototoxicity caused by the administration of cisplatin through the inhibition of mitochondrial dysfunction and suppression of ROS generation. KR-22335 may be considered as a potential candidate for protective agents against cisplatin-induced ototoxicity.

  7. Behavior of fission gases in nuclear fuel: XAS characterization of Kr in UO2

    Science.gov (United States)

    Martin, P. M.; Vathonne, E.; Carlot, G.; Delorme, R.; Sabathier, C.; Freyss, M.; Garcia, P.; Bertolus, M.; Glatzel, P.; Proux, O.

    2015-11-01

    X-ray Absorption Spectroscopy (XAS) was used to study the behavior of krypton as a function of its concentration in UO2 samples implanted with Kr ions. For a 0.5 at.% krypton local concentration, by combining XAS results and DFT + U calculations, we show that without any thermal treatment Kr atoms are mainly incorporated in the UO2 lattice as single atoms inside a neutral bound Schottky defect with O vacancies aligned along the (100) direction (BSD1). A thermal treatment at 1273 K induces the precipitation of dense Kr nano-aggregates, most probably solid at room temperature. In addition, 26 ± 2% of the Kr atoms remain inside BSD1 showing that Kr-BSD1 complex is stable up to this temperature. Consequently, the (in-)solubility of krypton in UO2 has to be re-evaluated. For high Kr concentration (8 at.%), XAS signals show that Kr atoms have precipitated in nanometer-sized aggregates with internal densities ranging between 4.15(7) g cm-3 and 3.98(5) g cm-3 even after annealing at 873 K. By neglecting the effect due to the UO2 matrix, the corresponding krypton pressures at 300 K were equal to 2.6(3) GPa and 2.0(2) GPa, respectively. After annealing at 1673 K, regardless of the initial Kr concentration, a bi-modal distribution is observed with solid nano-aggregates even at room temperature and larger cavities only partially filled with Kr. These results are very close to those observed in UO2 fuel irradiated in reactor. In this study we show that a rare gas can be used as a probe to investigate the defect creation and their stability in UO2.

  8. Ars Industrialis, arsindustrialis.org

    Directory of Open Access Journals (Sweden)

    Frédérique Mingant

    2012-03-01

    Full Text Available The arsindustrialis.org website was created in 2005, when the association Ars Industrialis came into being. The association was founded by a group of philosophers and jurists, on the initiative of philosopher Bernard Stiegler, the former director of the IRCAM (Institut de Recherche et Coordination Acoustique/Musique–Institute of Research and Coordination on Acoustic/Music and the current director of the Department of cultural development at the Centre Georges Pompidou (French National Arts C...

  9. Ars Industrialis, arsindustrialis.org

    OpenAIRE

    Frédérique Mingant

    2012-01-01

    The arsindustrialis.org website was created in 2005, when the association Ars Industrialis came into being. The association was founded by a group of philosophers and jurists, on the initiative of philosopher Bernard Stiegler, the former director of the IRCAM (Institut de Recherche et Coordination Acoustique/Musique–Institute of Research and Coordination on Acoustic/Music) and the current director of the Department of cultural development at the Centre Georges Pompidou (French National Arts C...

  10. ARS - Helsinki - 2006 / Galina Balashova

    Index Scriptorium Estoniae

    Balashova, Galina

    2006-01-01

    Steven Holli projekteeritud Kiasma muuseumihoonest Helsingis. Kontseptuaalkunsti näitusest ARS 06 "Reaalsustunne" Kiasmas. Eestlastest esineb Mark Raidpere. Vene kunstnikegrupi AEC+F ja vene kunstnike Juri Vassiljevi ning Aleksandr Ponomarjovi töödest näitusel. Ka Gerda Steineri & Jörg Lenzlingeri (Šveits), Martin & Munoz'i (USA, Hispaania), arvutigraafik Charles Sandisoni (SB), videokunstnik Bill Viola (USA) jt. töödest

  11. Ab initio ground and excited state potential energy surfaces for NO-Kr complex and dynamics of Kr solids with NO impurity.

    Science.gov (United States)

    Castro-Palacios, Juan Carlos; Rubayo-Soneira, Jesús; Ishii, Keisaku; Yamashita, Koichi

    2007-04-01

    The intermolecular potentials for the NO(X 2Pi)-Kr and NO(A 2Sigma+)-Kr systems have been calculated using highly accurate ab initio calculations. The spin-restricted coupled cluster method for the ground 1 2A' state [NO(X 2Pi)-Kr] and the multireference singles and doubles configuration interaction method for the excited 2 2A' state [NO(A 2Sigma+)-Kr], respectively, were used. The potential energy surfaces (PESs) show two linear wells and one that is almost in the perpendicular position. An analytical representation of the PESs has been constructed for the triatomic systems and used to carry out molecular dynamics (MD) simulations of the NO-doped krypton matrix response after excitation of NO. MD results are shown comparatively for three sets of potentials: (1) anisotropic ab initio potentials [NO molecule direction fixed during the dynamics and considered as a point (its center of mass)], (2) isotropic ab initio potentials (isotropic part in a Legendre polynomial expansion of the PESs), and (3) fitted Kr-NO potentials to the spectroscopic data. An important finding of this work is that the anisotropic and isotropic ab initio potentials calculated for the Kr-NO triatomic system are not suitable for describing the dynamics of structural relaxation upon Rydberg excitation of a NO impurity in the crystal. However, the isotropic ab initio potential in the ground state almost overlaps the published experimental potential, being almost independent of the angle asymmetry. This fact is also manifested in the radial distribution function around NO. However, in the case of the excited state the isotropic ab initio potential differs from the fitted potentials, which indicates that the Kr-NO interaction in the matrix is quite different because of the presence of the surrounding Kr atoms acting on the NO molecule. MD simulations for isotropic potentials reasonably reproduce the experimental observables for the femtosecond response and the bubble size but do not match

  12. GraXe, graphene and xenon for neutrinoless double beta decay searches

    CERN Document Server

    Gomez-Cadenas, J J; Fogler, M M; Katsnelson, M I; Martin-Albo, J; Monrabal, F; Muñoz-Vidal, J

    2011-01-01

    We propose a new detector concept, GraXe (to be pronounced as grace), to search for neutrinoless double beta decay in Xe-136. GraXe combines a popular detection medium in rare-event searches, liquid xenon, with a new, background-free material, graphene. Our baseline design of GraXe is a balloon made of graphene (possibly held together with a very thin structure made of radiopure fiber) and filled with xenon enriched in the Xe-136 isotope. The balloon is immersed in a large tank containing 20 tons of natural liquid xenon and instrumented with large photomultipliers. Liquid xenon is an excellent scintillator, reasonably transparent to its own light. Graphene is transparent over a large frequency range, an impermeable to the xenon. External backgrounds would be shielded by the buffer liquid xenon, and the inner volume has virtually zero background. Industrial graphene can be manufactured at a competitive cost to produce the inner balloon, and there is already near one ton of enriched Xenon available in the world...

  13. I-Xe measurements of CAIs and chondrules from the CV3 chondrites Mokoia and Vigarano

    Science.gov (United States)

    Whitby, J. A.; Russell, S. S.; Turner, G.; Gilmour, J. D.

    2004-08-01

    I-Xe analyses were carried out for chondrules and refractory inclusions from the two CV3 carbonaceous chondrites Mokoia and Vigarano (representing the oxidized and reduced subgroups, respectively). Although some degree of disturbance to the I-Xe system is evident in all of the samples, evidence is preserved of aqueous alteration of CAIs in Mokoia 1 Myr later than the I-Xe age of the Shallowater standard and of the alteration of a chondrule (V3) from Vigarano ~0.7 Myr later than Shallowater. Other chondrules in Mokoia and Vigarano experienced disturbance of the I-Xe system millions of years later and, in the case of one Vigarano chondrule (VS1), complete resetting of the I-Xe system after decay of essentially all 129I, corresponding to an age more than 80 Myr after Shallowater. Our interpretation is that accretion and processing to form the Mokoia and Vigarano parent bodies must have continued for at least 4 Myr and 80 Myr, respectively. The late age of a chondrule that shows no evidence for any aqueous alteration or significant thermal processing after its formation leads us to postulate the existence of an energetic chondrule-forming mechanism at a time when nebular processes are not expected to be important.

  14. Interpreting the I-Xe system in individual silicate grains from Toluca IAB

    Science.gov (United States)

    Pravdivtseva, O. V.; Meshik, A. P.; Hohenberg, C. M.; Petaev, M.

    2009-12-01

    Detailed isotopic and mineralogical studies of silicate inclusions separated from a troilite nodule of the Toluca IAB iron meteorite reveal the presence of radiogenic 129Xe in chlorapatite, plagioclase, perryite, and pyroxene grains. Subsequent I-Xe studies of 32 neutron-irradiated pyroxene grains indicate that high-Mg and low-Mg pyroxenes have distinctive I-Xe signatures. The I-Xe system in high-Mg pyroxenes closed at 4560.5 ± 2.4 Ma, probably reflecting exsolution of silicates from the melt, while the low-Mg pyroxenes closed at 4552.0 ± 3.7 Ma, 8.5 Ma later, providing a means for determining the cooling rate at the time of exsolution. If the host Toluca graphite-troiliterich inclusion formed after the breakup and reassembly of the IAB parent body as has been suggested, the I-Xe ages of the high-Mg pyroxenes separated from this inclusions indicate that this catastrophic impact occurred not later than 4560.5 Ma, 6.7 Ma after formation of CAIs. The cooling rate at the time of silicates exsolution in Toluca is 14.5 ± 10.0 °C/Ma.

  15. The characteristics of a negative corona discharge in He/Xe/SF6 mixture

    Science.gov (United States)

    Shuaibov, A. K.

    1999-02-01

    The results of investigation of the electrical and optical characteristics of a negative corona discharge in the electrode system of the type needle-grid lit in a He/Xe/SF6 mixture under the pressure of 100-300 kPa are presented in this paper. The given medium is working for a pulse-periodic excimer lamp on = 351 nm XeF(B-X). Distributed on the length of a lamp active media a bipolar corona discharge is intended for using in the electric circulation of the XeF-lamp working medium. It is shown that the given discharge is ignited steadily in the He/Xe/SF6 mixture, containing 0, 5kPa SF6 molecules and is characterised by a low power consumption; the current of the discharge is limited to the development of instability by increasing the voltage on the needles; in hot zones of corona discharge SF6 molecules cause the effective population 6s of XeI state.

  16. Finite element modeling of 129Xe diffusive gas exchange NMR in the human alveoli

    Science.gov (United States)

    Stewart, Neil J.; Parra-Robles, Juan; Wild, Jim M.

    2016-10-01

    Existing models of 129Xe diffusive exchange for lung microstructural modeling with time-resolved MR spectroscopy data have considered analytical solutions to one-dimensional, homogeneous models of the lungs with specific assumptions about the alveolar geometry. In order to establish a model system for simulating the effects of physiologically-realistic changes in physical and microstructural parameters on 129Xe exchange NMR, we have developed a 3D alveolar capillary model for finite element analysis. To account for the heterogeneity of the alveolar geometry across the lungs, we have derived realistic geometries for finite element analysis based on 2D histological samples and 3D micro-CT image volumes obtained from ex vivo biopsies of lung tissue from normal subjects and patients with interstitial lung disease. The 3D alveolar capillary model permits investigation of the impact of alveolar geometrical parameters and diffusion and perfusion coefficients on the in vivo measured 129Xe CSSR signal response. The heterogeneity of alveolar microstructure that is accounted for in image-based models resulted in considerable alterations to the shape of the 129Xe diffusive uptake curve when compared to 1D models. Our findings have important implications for the future design and optimization of 129Xe MR experiments and in the interpretation of lung microstructural changes from this data.

  17. High voltage studies of Xe-129 gas for the TRIUMF nEDM experiment

    Science.gov (United States)

    Katsika, Aikaterini; Canada-Japan UCN Collaboration Collaboration

    2016-09-01

    One of the main sources of systematic uncertainties in neutron electric dipole experiments (nEDM) experiments is related to magnetic field fluctuations. The idea of the atomic co-magnetometer, where polarized atoms are introduced in the same volume with ultra-cold neutrons and measure the precession frequencies of both species, has been used in the past with Hg-199 atoms and led to an improvement of the nEDM upper limit down to 3.010-26 ecm. For the TRIUMF nEDM experiment, we aim to use Xe-129 atoms expecting to suppress this limit ultimately by two orders of magnitude more due to the smaller neutron absorption cross section and the negative (same to that of the neutron) gyromagnetic ratio that Xe-129 possesses. The precession of the Xe-129 atoms will be probed via a two photon exchange process which requires enough Xe-129 atoms such that the pressure in the cell is orders of mTorr. The talk will present the status of the experimental work carried out at TRIUMF which is focused on exploring the dielectric properties of the Xe-129 in the mTorr region as we require a stable electric field of about 12.5 kV/cm in order to improve the current nEDM upper limit.

  18. NMR Study of Laser-polarized 129Xe in Low Pressure Natural Xenon Gas

    Institute of Scientific and Technical Information of China (English)

    SUN Xianping; WANG Shenglie; ZENG Xizhi

    2001-01-01

    The NMR signal from the laser-polarized t29 Xe in low-pressure natural xenon gas has been observed with a Bruker WP-80SY NMR spectrometer. The laser-polarized 129 Xe was produced by the method of laser pumping and spin exchange in a magnetic field of 1.87 Tesla. It is obtained experimentally that the nuclear spin relaxation rate 1/T1 of laser-polarized 129Xe are (4.03±1.97)×10-3/see~(2.21±0.78)×10-3/see in the range of the 3.33×103 Pa~8.29×104 Pa Xe gas pressures, the apparent wall relaxation rate 1/Tw* =(1.98±0.18)×10-3/see, and the relaxation rate coefficient C of 133Cs-129Xe spin exchange is (2.81±0.74)×10-16 em3/sec.

  19. Decay pathways after Xe 3d inner shell ionization using a multi-electron coincidence technique

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, I H; Nakano, M; Ito, K [Photon Factory, IMSS, KEK, Oho 1-1, Tsukuba, Ibaraki 305-0801 (Japan); Hikosaka, Y; Soejima, K [Department of Environmental Science, Niigata University, Niigata 950-2181 (Japan); Shigemasa, E [UVSOR Facility, Institute for Molecular Science, Okazaki, 444-8585 (Japan); Lablanquie, P; Penent, F [UPMC, Universite Paris 06, LCPMR, 11 rue de Pierre et Marie Curie, 75231 Paris Cedex 05 (France); Kouchi, N, E-mail: suzukii@post.kek.jp [Department of Chemistry, Tokyo Institute of Technology, O-okayama, Tokyo 152-8551 (Japan)

    2011-04-14

    Cascade Auger electron emission following Xe 3d photoionization has been investigated using a multi-electron coincidence technique, which utilizes an electron spectrometer of magnetic bottle type. It has been found that the Xe{sup 2+} states of the 4p{sup -1}4d{sup -1} configuration, formed by the Auger decay of the Xe{sup +} 3d{sub 3/2,5/2}{sup -1} states, dominantly turn into triply charged states of the 4d{sup -2}5p{sup -1}/4d{sup -2}5s{sup -1} configurations. The Xe{sup 2+} 4s{sup -1}4d{sup -1} states, formed by the 3d Auger decay, yield the 4p{sup -1}4d{sup -1}5p{sup -1} states as well as the 4d{sup -3} states. From the coincidence spectrum among three Auger electrons, it is suggested that the Xe{sup 2+} 4p{sup -1}4d{sup -1} states give rise to the following cascade processes: 4p{sup -1}4d{sup -1} {yields} 4d{sup -2}5p{sup -1} {yields} 4d{sup -1}5p{sup -3}.

  20. Low temperature anomaly of heat capacity of CD4 rotors in solid CD4-Kr solution

    OpenAIRE

    Bagatskii, M.I.; Dudkin, V. V.; Manzhelii, V. G.; Mashchenko, D. A.; Feodosiev, S. B.

    2004-01-01

    The heat capacity of the solid Kr-CD4 (13% CD4) solution has been investigated. It is shown that the temperature dependence of the heat capacity Crot of the rotational subsystem in this solution is radically different from the corresponding dependences in the previously studied Kr-CD4 (1%, 5% CD4) and Kr-CH4 (5-60%) solutions. A model is proposed to explain the observed dependence Crot(T). The experimental results can be described taking into account the contribution to the heat capacity from...

  1. Excited state dynamics of Kr N clusters probed with time- and energy-resolved photoluminescence methods

    Science.gov (United States)

    Karnbach, R.; Castex, M. C.; Keto, J. W.; Joppien, M.; Wörmer, J.; Zimmerer, G.; Möller, T.

    1993-02-01

    Excitation and decay processes in Kr N clusters ( N=2-10 4) were investigated via time- and energy-resolved fluorescence methods with synchrotron radiation excitation. In small clusters ( N<50) in addition to the well-known emission bands of condensed Kr another broad continuous emission is observed. It is assigned to a radiative decay of Kr excimers desorbing from the cluster surface. There are indications that the cluster size where the desorption rate becomes slow is related to a change in sign of the electron affinity of the cluster. Changes of spectral distribution of the fluorescence light with cluster size are interpreted as variations of the vibrational energy flow.

  2. Spectra and electromagnetic transitions of 72-84Kr in the interacting boson model-1

    Science.gov (United States)

    Bai, Hong-Bo; Li, Xiao-Wei; Lü, Li-Jun; Dong, Hong-Fei; Wang, Yin; Zhang, Jin-Fu

    2016-07-01

    Within the framework of the interacting boson model-1, the energy levels and electromagnetic transitions in 72-84Kr isotopes are calculated. The structures of the eigenstate and Hamiltonian matrix for some low-lying states are also calculated. The calculated results are compared with available experimental data, and the results are generally in good agreement. The present study shows that the 72,74,76,80,82,84Kr isotopes are in the transition from U(5) → SU(3), and 78Kr is in the transition from U(5) → O(6). Supported by NSFC(11465001,11165001) and Natural Science Foundation of Inner Mongolia of China (2013MS0117)

  3. Mixed municipal solid waste (MSW) treatment in Waste centre Spodnji Stari Grad, Krško

    OpenAIRE

    Kortnik, Jože; Leskovar, Jože

    2015-01-01

    Review paper Received: October 25, 2013 Accepted: November 7, 2013 Mixed municipal solid waste (MSW) treatment in Waste centre Spodnji Stari Grad, Krško Ravnanje z mešanimi komunalnimi odpadki v Zbirnem centru Spodnji Stari Grad, Krško Jože Kortnik1'*, Jože Leskovar2 University of Ljubljana, Faculty of Natural Sciences and Engineering, Department of Mining and Geotechnology, Aškerčeva 12, 1000 Ljubljana, Slovenia 2Kostak, d. d., Leskovška cesta 2a, 8270 Krško, Slovenia Correspo...

  4. 有一个实现包含Kr+1的可图序列%Graphic Sequences that Have a Realization Containing an Kr+1

    Institute of Scientific and Technical Information of China (English)

    尹建华

    2009-01-01

    Kr+1是一个r+1个顶点的完全图.一个可图序列π=(d1,d2,…,dn)称为是蕴含Kr+1-可图的,如果π有一个实现包含Kr+1作为子图.该文进一步研究了蕴含Kr+1-可图序列的一些新的条件,证明了这些条件包含文献[14,10,11]中的一些主要结果和当n≥5r/2+1时,σ(Kr+1,n)之值(此值在文献[2]中被猜测,在文献[6,7,8,3]中被证实).此外,确定了所有满足n≥5,d5≥4且不蕴含K5-可图序列π=(d1,d2,…,dn)的集合.

  5. CORRELATION EFFECTS AND STRUCTURES FOR WEAKLY BOUND MOLECULE Kr-HF%弱结合分子Kr-HF结构与相关效应

    Institute of Scientific and Technical Information of China (English)

    蒋刚; 谢洪平; 谭明亮; 朱正和

    2000-01-01

    采用二阶、三阶Moller-Plesset微扰理论方法(MP2,MP3),组态相互作用方法(QCISD)在不同的基组下对弱结合分子体系Kr-HF进行了ab initio计算,得到了Kr-HF体系的两个不同的线型平衡几何结构:Kr-HF和Kr-FH.对于Kr-HF分子,在MP2/6-311++G**水平上得到Kr与HF分子中心的间距为0.37787nm,离解能为6.1480eV,谐振频率分别为ν1(σ)=4187.9638cm-1,ν2(π)=162.2953cm-1,ν3(σ)=41.8689cm-1.并计算得到了这两个分子构型的热力学常量和谐性力常量.进一步考察了不同基组和方法对弱结合分子的影响.

  6. Surface Tension of Mixtures of Molecular Fluids: Comparison between the Experimental and Theoretical Study of CH4 + Kr, Kr + NO, and CH4 + NO

    Science.gov (United States)

    Calado; Mendonca; Saramago; Soares

    1997-01-01

    We report a study of the surface tension of three binary liquid mixtures of molecular fluids. A microscopic mean field theory (MFT) has been used to calculate the theoretical results enabling the comparison with the experimental data. The mean field theory has been successfully used in the prediction of the surface properties of simple systems composed by quasi-spherical molecules. In the present study the MFT was able to reproduce the essential features of the interfacial properties of the systems CH4 + Kr, Kr + NO and CH4 + NO. The pure components were modeled by Lennard-Jones potentials with a set of intermolecular parameters taken from the literature for Kr and calculated from the fitting of the energy parameters (epsilon) to the surface tension, for CH4 and NO. In the case of the mixtures, it was found that reasonable agreement with experiment can only be obtained by allowing deviations from the Lorentz-Berthelot combining rules. For the CH4 + Kr system we used the binary energy parameter xi obtained through a fitting to the bulk properties; for the Kr + NO and CH4 + NO systems the binary parameter was adjusted to the interfacial properties.

  7. Surface tension of mixtures of molecular fluids: Comparison between the experimental and theoretical study of CH{sub 4} + Kr, Kr + NO, and CH{sub 4} + NO

    Energy Technology Data Exchange (ETDEWEB)

    Calado, J.C.G.; Saramago, B.J.V. [Instituto Superior Tecnico, Lisbon (Portugal). Centro de Quimica Estrutural; Santos Mendonca, A.F.S. dos; Soares, V.A.M. [Univ. de Lisboa, Lisbon (Portugal). Centro de Ciencia e Tecnologia de Materiais

    1997-01-01

    The authors report a study of the surface tension of three binary liquid mixtures of molecular fluids. A microscopic mean field theory (MFT) has been used to calculate the theoretical results enabling the comparison with the experimental data. The mean field theory has been successfully used in the prediction of the surface properties of simple systems composed by quasi-spherical molecules. In the present study the MFT was able to reproduce the essential features of the interfacial properties of the systems CH{sub 4} + Kr, Kr + NO and CH{sub 4} + NO. The pure components were modeled by Lennard-Jones potentials with a set of intermolecular parameters taken from the literature for Kr and calculated from the fitting of the energy parameters to the surface tension, for CH{sub 4} and NO. In the case of the mixtures, it was found that reasonable agreement with experiment can only be obtained by allowing deviations from the Lorentz-Berthelot combining rules. For the CH{sub 4} + Kr system the authors used the binary energy parameter {xi} obtained through a fitting to the bulk properties; for the Kr + NO and CH{sub 4} + NO systems the binary parameter was adjusted to the interfacial properties.

  8. Oxidizing behavior of some platinum metal fluorides. [Xe complexes with Pt, Pd fluorides; Chlorine-2 oxidation by transition metal hexafluorides

    Energy Technology Data Exchange (ETDEWEB)

    Graham, L.

    1978-10-01

    The previously known compounds Xe/sub 2/F/sub 3//sup +/PtF/sub 6//sup -/, XeF/sup +/PtF/sub 6//sup -/ and XeF/sub 2/.2PtF/sub 4/(XePt/sub 2/F/sub 10/) were prepared by the interaction of XeF/sub 2/ with PtF/sub 4/. The new compounds XeF/sub 2/.PdF/sub 4/ and XeF/sub 2/.2PdF/sub 4/(XePd/sub 2/F/sub 10/) were produced by interaction of XeF/sub 2/ with either PdF/sub 4/ or Pd/sub 2/F/sub 6/. A weight loss-versus-time curve indicated the presence of 4:1, 3:1 and 2:1 XeF/sub 2//PdF/sub 4/ complexes. The thermal decomposition of XeFPtF/sub 6/ or XePd/sub 2/F/sub 10/ yields highly pure XeF/sub 4/. Thus the interaction of XeF/sub 2/ with platinum fluorides (PtF/sub 4/ or PtF/sub 5/) or palladium fluorides (Pd/sub 2/F/sub 6/ or PdF/sub 4/) provides for the conversion of XeF/sub 2/ to XeF/sub 4/. The compound XePd/sub 2/F/sub 10/ is a close structural relative of XePt/sub 2/F/sub 10/, and spectroscopic evidence suggests that both are salts of XeF/sup +/ and a polymeric (M/sub 2/F/sub 9/)/sub x//sup x-/ ion. A Xe:PtF/sub 6/ material of approximately 1:1 stoichiometry has been prepared and compared with XePdF/sub 6/(XeF/sub 2/.PdF/sub 4/). The interaction of chlorine with the third-series transition metal hexafluorides has been investigated. Gravimetric and tensimetric evidence indicate that the initial product of the Cl/sub 2/ plus IrF/sub 6/ reaction is a solid of composition Cl/sub 2/IrF/sub 6/. Vibrational spectroscopic and other evidence indicates that this solid yields a sequence of products, of which Cl/sub 3//sup +/IrF/sub 6//sup -/, Cl/sub 3//sup +/Ir/sub 2/F/sub 11//sup -/ and Ir/sub 4/F/sub 20/ have been identified, the last being the ultimate solid product of the room temperature decomposition of the adduct. A new chlorine fluoride generated in the room temperature decomposition of Cl/sub 2/IrF/sub 6/ has been tentatively formulated as Cl/sub 3/F from infrared evidence.

  9. Dissecting the role of Kr-h1 brain gene expression in foraging behavior in honey bees (Apis mellifera).

    Science.gov (United States)

    Fussnecker, B; Grozinger, C

    2008-09-01

    Expression of Krüppel homolog-1 (Kr-h1) in the honey bee brain is strongly associated with foraging behavior. We performed a series of studies to determine if Kr-h1 expression correlates with specific aspects of foraging. We found that Kr-h1 expression is unaffected by flight experience in male bees. Expression was unaffected by behavioral reversion of workers from foraging to brood care, suggesting that expression is not associated with the active performance of foraging, but rather with stable physiological changes. Kr-h1 expression is increased by cGMP treatment in workers, and the Kr-h1 promoter contains a conserved potential cGMP response element. Since cGMP treatment causes precocious foraging, our results suggest that Kr-h1 expression is associated with cGMP-mediated changes in the brain that occur early in the transition to foraging behavior.

  10. Occurrences of Excess 40Ar in Hydrothermal Tourmaline:Interpretations from 40Ar-39Ar Dating Results by Stepwise Heating

    Institute of Scientific and Technical Information of China (English)

    QIU Huaning; PU Zhiping; DAI Tongmo

    2007-01-01

    The occurrences of excess 40Ar within a hydrothermal tourmaline is discussed in term of the analysis data of syngenetic muscovite and tourmaline from the Lushui hydrothermal tin-tungsten deposit in western Yunnan, China, using the 40Ar-39Ar stepwise heating technique. About 80% excess 40Ar was released in the last step when the tourmaline was fused, corresponding to a release of only ~3% 39Ar (K), which indicates that most excess 40Ar was held in the mineral lattice rather than in the channels parallel to the Z-axis. This suggests that the excess 40Ar was incorporated during crystallization and not diffused into the tourmaline during the post-crystallization history.

  11. Analysis of Selected Legacy 85Kr Samples

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-09-02

    Legacy samples composed of 85Kr encapsulated in solid zeolite 5A material and five small metal tubes containing a mixture of the zeolite combined with a glass matrix resulting from hot isostatic pressing have been preserved. The samples were a result of krypton R&D encapsulation efforts in the late 1970s performed at the Idaho Chemical Processing Plant. These samples were shipped to Oak Ridge National Laboratory (ORNL) in mid-FY 2014. Upon receipt the outer shipping package was opened, and the inner package, removed and placed in a radiological hood. The individual capsules were double bagged as they were removed from the inner shipping pig and placed into individual glass sample bottles for further analysis. The five capsules were then x-ray imaged. Capsules 1 and 4 appear intact and to contain an amorphous mass within the capsules. Capsule 2 clearly shows the saw marks on the capsule and a quantity of loose pellet or bead-like material remaining in the capsule. Capsule 3 shows similar bead-like material within the intact capsule. Capsule 5 had been opened at an undetermined time in the past. The end of this capsule appears to have been cut off, and there are additional saw marks on the side of the capsule. X-ray tomography allowed the capsules to be viewed along the three axes. Of most interest was determining whether there was any residual material in the closed end of Capsule 5. The images confirmed the presence of residual material within this capsule. The material appears to be compacted but still retains some of the bead-like morphology. Based on the nondestructive analysis (NDA) results, a proposed path forward was formulated to advance this effort toward the original goals of understanding the effects of extended storage on the waste form and package. Based on the initial NDA and the fact that there are at least two breached samples, it was proposed that exploratory tests be conducted with the breached specimens before opening the three intact

  12. Comparison of 85KR and 3H Apparent Ground-Water Ages for Source Water Vulterability in the COLLYER RIVER CATCHMENT, MAINE

    Science.gov (United States)

    Apparent ground-water ages as determined by the noble gas isotope 85Kr and the water isotope 3H are compared. Refined gas extraction methodology at the wellhead permits efficient collection of Kr for 85Kr isotope enrichment. 85Kr isoch...

  13. Relaxation rates of low-field gas-phase ^129Xe storage cells

    Science.gov (United States)

    Limes, Mark; Saam, Brian

    2010-10-01

    A study of longitudinal nuclear relaxation rates T1 of ^129Xe and Xe-N2 mixtures in a magnetic field of 3.8 mT is presented. In this regime, intrinsic spin relaxation is dominated by the intramolecular spin-rotation interaction due to persistent xenon dimers, a mechanism that can be quelled by introducing large amounts of N2 into the storage cell. Extrinsic spin relaxation is dominated by the wall-relaxation rate, which is the primary quantity of interest for the various low-field storage cells and coatings that we have tested. Previous group work has shown that extremely long gas-phase relaxation times T1 can be obtained, but only at large magnetic fields and low xenon densities. The current work is motivated by the practical benefits of retaining hyperpolarized ^129Xe for extended periods of time in a small magnetic field.

  14. EDM measurement in {sup 129}Xe atom using dual active feedback nuclear spin maser

    Energy Technology Data Exchange (ETDEWEB)

    Sato, T., E-mail: sato@yap.nucl.ap.titech.ac.jp [Tokyo Institute of Technology, Department of Physics (Japan); Ichikawa, Y. [RIKEN Nishina Center (Japan); Ohtomo, Y.; Sakamoto, Y.; Kojima, S.; Funayama, C.; Suzuki, T.; Chikamori, M.; Hikota, E.; Tsuchiya, M. [Tokyo Institute of Technology, Department of Physics (Japan); Furukawa, T. [Tokyo Metropolitan University, Department of Physics (Japan); Yoshimi, A. [Okayama University, Research Core for Extreme Quantum World (Japan); Bidinosti, C. P. [University of Winnipeg, Department Physics (Canada); Ino, T. [Institute of Material Structure Science, KEK (Japan); Ueno, H. [RIKEN Nishina Center (Japan); Matsuo, Y. [Hosei University, Department of Advanced Sciences (Japan); Fukuyama, T. [Osaka University, RCNP (Japan); Asahi, K. [Tokyo Institute of Technology, Department of Physics (Japan)

    2015-04-15

    The technique of an active nuclear spin maser is adopted in the search for electric dipole moment in a diamagnetic atom {sup 129}Xe. In order to reduce systematic uncertainties arising from long-term drifts of the external magnetic field and from the contact interaction between longitudinal polarized Rb atoms and {sup 129}Xe spin, a {sup 3}He comagnetometer with a double-cell geometry was employed. The remaining shift, which turned out to show some correlation with the cell temperature, was mitigated by stabilizing the cell temperature. As a result, the frequency drift of the {sup 129}Xe maser was reduced from 12 mHz to 700 μHz, and the determination precision of frequency of 8.7 nHz was obtained for a 2×10{sup 4} s measurement time using the double-cell geometry cell.

  15. A new search for the permanent electric dipole moment of 129Xe at FRM-II

    Science.gov (United States)

    Sachdeva, N.; Chupp, T.; Degenkolb, S.; Fierlinger, P.; Kraegloh, E.; Kuchler, F.; Lins, T.; Meinel, J.; Niessen, B.; Stuiber, S.; Terrano, W. A.; Burghoff, M.; Fan, I.; Kilian, W.; Grüneberg, S.; Schnabel, A.; Seifert, F.; Stollfuss, D.; Trahms, L.; Voight, J.; Babcock, E.; Salhi, Z.; Huneau, J.; Singh, J.

    2017-01-01

    CP-violating sources in beyond-the-standard-model physics, necessary to explain baryon asymmetry, give rise to permanent electric dipole moments (EDMs). Precise EDM measurements of the neutron, electron, paramagnetic and diamagnetic atoms constrain CP-violating parameters. The previous limit for the 129Xe EDM is 6 ×10-27 e . cm (95 % CL). The HeXeEDM experiment at FRM-II (Munich Research Reactor) utilizes an ultralow magnetic field in a high-performance magnetically shielded room and 3He comagnetometer to improve the limit by up to three orders of magnitude. In the experiment, hyperpolarized 3He and 129Xe precession signals are detected with a SQUID magnetometer array in the presence of applied electric and magnetic fields. Recent progress will be presented. This work is supported US Department of Energy Grant No. DE FG02 04 ER41331.

  16. Detection of $^{133}$Xe from the Fukushima nuclear power plant in the upper troposphere above Germany

    CERN Document Server

    Simgen, Hardy; Aufmhoff, Heinfried; Baumann, Robert; Kaether, Florian; Lindemann, Sebastian; Rauch, Ludwig; Schlager, Hans; Schlosser, Clemens; Schumann, Ulrich

    2013-01-01

    After the accident in the Japanese Fukushima Dai-ichi nuclear power plant in March 2011 large amounts of radioactivity were released and distributed in the atmosphere. Among them were also radioactive noble gas isotopes which can be used as tracers to probe global atmospheric circulation models. This work presents unique measurements of the radionuclide $^{133}$Xe from Fukushima in the upper troposphere above Germany. The measurements involve air sampling in a research jet aircraft followed by chromatographic xenon extraction and ultra-low background gas counting with miniaturized proportional counters. With this technique a detection limit of the order of 100 $^{133}$Xe atoms in liter-scale air samples (corresponding to about 100 mBq/m$^3$) is achievable. Our results proof that the $^{133}$Xe-rich ground level air layer from Fukushima was lifted up to the tropopause and distributed hemispherically. Moreover, comparisons with ground level air measurements indicate that the arrival of the radioactive plume in ...

  17. I-Xe systematics of the impact plume produced chondrules from the CB carbonaceous chondrites: Implications for the half-life value of 129I and absolute age normalization of 129I-129Xe chronometer

    Science.gov (United States)

    Pravdivtseva, O.; Meshik, A.; Hohenberg, C. M.; Krot, A. N.

    2017-03-01

    It is inferred that magnesian non-porphyritic chondrules in the CB (Bencubbin-type) carbonaceous chondrites formed in an impact generated plume of gas and melt at 4562.49 ± 0.21 Ma (Bollard et al., 2015) and could be suitable for the absolute age normalization of relative chronometers. Here xenon isotopic compositions of neutron irradiated chondrules from the CB chondrites Gujba and Hammadah al Hamra (HH) 237 have been analyzed in an attempt to determine closure time of their I-Xe isotope systematics. One of the HH 237 chondrules, #1, yielded a well-defined I-Xe isochron that corresponds to a closure time of 0.29 ± 0.16 Ma after the Shallowater aubrite standard. Release profiles and diffusion properties of radiogenic 129*Xe and 128*Xe, extracted from this chondrule by step-wise pyrolysis, indicate presence of two iodine host phases with distinct activation energies of 73 and 120 kcal/mol. In spite of the activation energy differences, the I-Xe isotope systematics of these two phases closed simultaneously, suggesting rapid heating and cooling (possibly quenching) of the CB chondrules. The release profiles of U-fission Xe and I-derived Xe correlate in the high temperature host phase supporting simultaneous closure of 129I-129Xe and 207Pb-206Pb systematics. The absolute I-Xe age of Shallowater standard is derived from the observed correlation between I-Xe and Pb-Pb ages in a number of samples. It is re-evaluated here using Pb-Pb ages adjusted for an updated 238U/235U ratio of 137.794 and meteorite specific U-isotope ratios. With the addition of the new data for HH 237 chondrule #1, the re-evaluated absolute I-Xe age of Shallowater is 4562.4 ± 0.2 Ma. The absolute I-Xe age of the HH 237 chondrule #1 is 4562.1 ± 0.3 Ma, in good agreement with U-corrected Pb-Pb ages of the Gujba chondrules (Bollard et al., 2015) and HH 237 silicates (Krot et al., 2005). All I-Xe data used here, and in previous estimates of the absolute age of Shallowater, are calculated using 15.7

  18. Analysis of dynamical behavior of reactions associated with 118,120,122Xe* isotopes

    Science.gov (United States)

    Grover, Neha; Sharma, Ishita; Kaur, Gurvinder; Sharma, Manoj K.

    2017-03-01

    In reference to recent experiment, the dynamical aspects of reactions forming even mass isotopes of 118,120,122Xe* nuclei are examined using the collective clusterization approach and the ℓ-summed Wong model. The role of excitation energy (or temperature), deformations, orientations and angular momentum etc. has been investigated for the 28Si + 90,92,94Zr reactions. In order to account for the role of deformations, the evaporation residue (ER) cross sections of 122Xe* nucleus have been studied in reference to the available experimental data by using spherical as well as deformed fragmentation approach. We have used optimum and compact orientations respectively for β2 alone and for β4 included, which inturn provide nice agreement with the available experimental cross-sections. Also, the effect of isospin (N/Z ratio) of decay fragments has been explored in view of the fragmentation analysis and preformation probability of 118,120,122Xe* nuclei. Additionally, the role of projectile nucleus is also explored by studying the fragmentation path of 118Xe* nucleus in comparison to 123Ba* system. Further, the ER cross-sections have been predicted for various even mass isotopes of 116,118,120,124Xe. In addition to this, to explore the fusion characteristics of 28Si + 90,92,94Zr reactions, the Wong model as well as the ℓ-summed Wong model has also been employed. Here also, the role of deformation in formation of 122Xe* nucleus has been examined and the calculated cross-sections find decent agreement with the experimental data.

  19. Hyperpolarized 129Xe magnetic resonance imaging of a rat model of transient Ischemic Stroke

    Science.gov (United States)

    Walvick, Ronn P.; Bastan, Birgul; Reno, Austin; Mansour, Joey; Sun, Yanping; Zhou, Xin; Mazzani, Mary; Fisher, Marc; Sotak, Christopher H.; Albert, Mitchell S.

    2009-02-01

    Ischemic stroke accounts for nearly 80% of all stroke cases. Although proton diffusion and perfusion magnetic resonance imaging (MRI) are the gold standards in ischemic stroke diagnostics, the use of hyperpolarized 129Xe MRI has a potential role to contribute to the diagnostic picture. The highly lipophilic hyperpolarized 129Xe can be non-invasively delivered via inhalation into the lungs where it is dissolved into the blood and delivered to other organs such as the brain. As such, we expect hyperpolarized 129Xe to act as a perfusion tracer which will result in a signal deficit in areas of blood deprived tissue. In this work, we present imaging results from an animal model of transient ischemic stroke characterized through 129Xe MRI. In this model, a suture is used to occlude the middle cerebral artery (MCA) in the rat brain, thus causing an ischemic event. After a period of MCA occlusion, the suture can then be removed to reperfuse the ischemic area. During the ischemic phase of the stroke, a signal void was observed in the MCA territory; which was subsequently restored by normal 129Xe MRI signal once perfusion was reinstated. Further, a higher resolution one-dimensional chemical shift image shows a sharp signal drop in the area of ischemia. Validation of ischemic damage was shown through both proton diffusion-weighted MRI (DWI) and by 2,3,5-triphenyltetrazoliumchloride (TTC) staining. The results show the potential of 129Xe to act as a perfusion tracer; information that may add to the diagnostic and prognostic utility of the clinical picture of stroke.

  20. Hyperpolarized {sup 129}Xe MRI: A viable functional lung imaging modality?

    Energy Technology Data Exchange (ETDEWEB)

    Patz, Samuel [Center for Pulmonary Functional Imaging, Brigham and Women' s Hospital, 221 Longwood Avenue, Boston, MA 02115 (United States); Department of Radiology, Brigham and Women' s Hospital, 75 Francis Street, Boston, MA 02115 (United States)], E-mail: patz@bwh.harvard.edu; Hersman, F. William [Department of Physics, University of New Hampshire, 131 Main Street, Nesmith Hall, Durham, NH 03824 (United States); Muradian, Iga [Center for Pulmonary Functional Imaging, Brigham and Women' s Hospital, 221 Longwood Avenue, Boston, MA 02115 (United States); Department of Radiology, Brigham and Women' s Hospital, 75 Francis Street, Boston, MA 02115 (United States); Hrovat, Mirko I. [Mirtech, Inc., 452 Ash Street, Brockton, MA 02301 (United States); Ruset, Iulian C.; Ketel, Stephen [Department of Physics, University of New Hampshire, 131 Main Street, Nesmith Hall, Durham, NH 03824 (United States); Jacobson, Francine [Department of Radiology, Brigham and Women' s Hospital, 75 Francis Street, Boston, MA 02115 (United States); Topulos, George P. [Department of Anesthesiology, Brigham and Women' s Hospital, 75 Francis Street, Boston, MA 02115 (United States); Hatabu, Hiroto [Center for Pulmonary Functional Imaging, Brigham and Women' s Hospital, 221 Longwood Avenue, Boston, MA 02115 (United States); Department of Radiology, Brigham and Women' s Hospital, 75 Francis Street, Boston, MA 02115 (United States); Butler, James P. [Department of Environmental Health, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115 (United States)

    2007-12-15

    The majority of researchers investigating hyperpolarized gas MRI as a candidate functional lung imaging modality have used {sup 3}He as their imaging agent of choice rather than {sup 129}Xe. This preference has been predominantly due to, {sup 3}He providing stronger signals due to higher levels of polarization and higher gyromagnetic ratio, as well as its being easily available to more researchers due to availability of polarizers (USA) or ease of gas transport (Europe). Most researchers agree, however, that hyperpolarized {sup 129}Xe will ultimately emerge as the imaging agent of choice due to its unlimited supply in nature and its falling cost. Our recent polarizer technology delivers vast improvements in hyperpolarized {sup 129}Xe output. Using this polarizer, we have demonstrated the unique property of xenon to measure alveolar surface area noninvasively. In this article, we describe our human protocols and their safety, and our results for the measurement of the partial pressure of pulmonary oxygen (pO{sub 2}) by observation of {sup 129}Xe signal decay. We note that the measurement of pO{sub 2} by observation of {sup 129}Xe signal decay is more complex than that for {sup 3}He because of an additional signal loss mechanism due to interphase diffusion of {sup 129}Xe from alveolar gas spaces to septal tissue. This results in measurements of an equivalent pO{sub 2} that accounts for both traditional T{sub 1} decay from pO{sub 2} and that from interphase diffusion. We also provide an update on new technological advancements that form the foundation for an improved compact design polarizer as well as improvements that provide another order-of-magnitude scale-up in xenon polarizer output.

  1. Calculation of scanning tunnelling microscopy images for Kr/graphite system

    Institute of Scientific and Technical Information of China (English)

    周晓林; 陈向荣; 杨向东; 芶清泉

    2003-01-01

    The scanning-tunnelling-microscopy(STM)images of Kr atoms adsorbed on a monolayer graphite sheet(Kr/graphite system)are calculated using the first-principle total-energy electronic structure calculations within the density functional theory in the local density approximation.The results obtained agree well with the observations.It is found that the optimal site of the adsorbed Kr atom is at the top of the centre of the carbon hexagon,and its equilibrium distance from monolayer graphite surface is about 0.335nm.It is shown that the hybridization of C 2p electronic states(π-electronic states)and Kr 4p and 5s electronic states is the main origin of the Fermi-level local density of state.

  2. Hyperpolarized 3He MRI and 81mKr SPECT in chronic obstructive pulmonary disease

    DEFF Research Database (Denmark)

    Stavngaard, Trine; Søgaard, Lise; Mortensen, J;

    2005-01-01

    was to compare ventilation imaging methods in 26 patients with chronic obstructive pulmonary disease (COPD) and nine lung healthy volunteers. METHODS: HP 3He MRI, 81mKr single-photon emission computed tomography (SPECT), high-resolution computed tomography (HRCT) and pulmonary function tests were performed...... visual defect score (r=0.80, ppulmonary function test and HRCT). The defect scores were largest on 81mKr SPECT (the score on HP 3He MRI...... was one-third less than that on 81mKr SPECT), but the difference was reduced after normalisation for different breathing depths (HP 3He MRI at total lung capacity; 81mKr SPECT at tidal breathing at functional residual capacity). CONCLUSION: HP 3He MRI provides detailed ventilation distribution images...

  3. Noor koreograaf Krõõt Juurak sai imel sabast kinni / Tiiu Laks

    Index Scriptorium Estoniae

    Laks, Tiiu, 1984-

    2006-01-01

    Tantsulavastusest "Once upon" Kanuti Gildi saalis. Esietendus 12. okt. Idee ja esitus Krõõt Juurak. Valminud prooviperioodide tulemusel Viinis, PAFis Prantsusmaal ja Tallinnas. Etendub 6. dets. ka Austrias Dietheater Küntslerhausis Viinis

  4. Ars Memorativa, Ars Oblivionis in Middle English Religious Plays

    Directory of Open Access Journals (Sweden)

    Ciobanu Estella Antoaneta

    2015-12-01

    Full Text Available This paper investigates the multi-layered violence of religious representation in the late medieval York biblical plays, with a focus on the Supper at Emmaus. I read Emmaus (Y40, a play which commemorates the Crucifixion and openly encourages strong anti-Judaism, alongside scenes in an early predecessor pageant, The Crucifixion (Y35, within their contemporary devotional and mnemonic practices, i.e. the confessional Book of Margery Kempe and Thomas Bradwardine’s tract on ars memorativa. Emmaus in particular demonstrates how a fundamentally violent ars memorativa, the legacy of ancient rhetoric to the Middle Ages, also underpins the instruction of the laity in the basics of Christian faith, here with the aid of highly musical prosody and repetition, and thereby hones a biased, intolerant and violence-inured Christian collective memory. To study the York play’s position relative to late medieval mnemonic practices, I frame my analysis within memory studies, enriched with the more specific insights offered by social-psychological, neurobiological and cognitivist studies of memory.

  5. Recent improvements of a mobile polarizer system for {sup 129}Xe

    Energy Technology Data Exchange (ETDEWEB)

    Stahl, Vanessa; Heil, Werner; Karpuk, Sergei; Bluemler, Peter; Repetto, Maricel; Niederlaender, Benjamin; Braun, Manuel; Fuchs, Martin [Institut fuer Physik, Universitaet Mainz (Germany); Muennemann, Kerstin; Spiess, Hans [Max Planck Institute for Polymer Research Mainz (Germany)

    2013-07-01

    (HP){sup 129}Xe has numerous applications both in fundamental physics like nuclear spin clocks and in medical research, e.g. in lung MRI. We report on a compact mobile {sup 129}Xe polarizer built in order to achieve high polarization degrees operating in counter flow. The optical pumping scheme is optimized in terms of magnetic field homogeneity, rubidium saturation, freeze-thaw method, gas-transport and its storage in special vessels with low wall relaxation. This talk will cover different aspects of HP gas production, manipulation and minimization of losses due to relaxation.

  6. Effect of Frequency on Emission of XeIast Excimer in a Pulsed Dielectric Barrier Discharge

    Science.gov (United States)

    Ou, Qiong-Rong; Meng, Yue-Dong; Xu, Xu; Shu, Xing-Sheng; Ren, Zhao-Xing

    2004-07-01

    Emission spectra of XeIast excimers and ultraviolet intensity at 253 nm from a dielectric barrier discharge (DBD) lamp excited by a pulsed voltage were measured as functions of pressure, electrical power, and frequency. In the DBD lamp driven by a higher frequency voltage, a more intense emission of XeIast excimers with high efficiency at 253 nm was found. A diffuse discharge mode was observed at high xenon pressure (>1 atm) with an excessive iodine concentration in the DBD driven by a high frequency (60 kHz) voltage.

  7. Effect of Frequency on Emission of XeI* Excimer in a Pulsed Dielectric Barrier Discharge

    Institute of Scientific and Technical Information of China (English)

    OU Qiong-Rong; MENG Yue-Dong; XU Xu; SHU Xing-Sheng; REN Zhao-Xing

    2004-01-01

    Emission spectra of XeI* excimers and ultraviolet intensity at 253 nm from a dielectric barrier discharge (DBD)lamp excited by a pulsed voltage were measured as functions of pressure, electrical power, and frequency. In the DBD lamp driven by a higher frequency voltage, a more intense emission of XeI* excimers with high efficiency at 253 nm was found. A diffuse discharge mode was observed at high xenon pressure (> 1 atm) with an excessive iodine concentration in the DBD driven by a high frequency (60 kHz) voltage.

  8. Generation of nanosecond pulses in a barrier-discharge XeBr excimer lamp

    Science.gov (United States)

    Avdeev, S. M.; Kostyrya, I. D.; Sosnin, É. A.; Tarasenko, V. F.

    2006-07-01

    The subject of investigation is the coaxial two-barrier short-pulse excimer lamp based on XeBr* molecules (λ = 282 nm). When the working mixture (Xe: Br2 = 70: 1) is excited by a high-voltage pulsed nanosecond discharge at a pressure of 1 atm, the peak power of the generated radiation is on the order of 100 kW at an FWHM of 4.5 ns. If the gap between the barriers is small, a train of pulses with an FWHM of 20 ns and a repetition rate of 200 kHz may be obtained.

  9. Rearrangement of valence neutrons in the neutrinoless double-$\\beta$ decay of $^{136}$Xe

    CERN Document Server

    Szwec, S V; Cocolios, T E; Entwisle, J P; Freeman, S J; Gaffney, L P; Guimarães, V; Hammache, F; McKee, P P; Parr, E; Portail, C; Schiffer, J P; de Séréville, N; Sharp, D K; Smith, J F; Stefan, I

    2016-01-01

    A quantitative description of the change in ground-state neutron occupancies between $^{136}$Xe and $^{136}$Ba, the initial and final state in the neutrinoless double-$\\beta$ decay of $^{136}$Xe, has been extracted from precision measurements of the cross sections of single-neutron adding and -removing reactions. Comparisons are made to recent theoretical calculations of the same properties using various nuclear-structure models. These are the same calculations used to determine the magnitude of the nuclear matrix elements for the process, which at present disagree with each other by factors of 2 or 3. The experimental neutron occupancies show some disagreement with the theoretical calculations.

  10. Lung function assessment using Xe-133 dynamic SPECT in dual-camera system

    Energy Technology Data Exchange (ETDEWEB)

    Sakaji, Katsuyuki; Akiyama, Masayuki; Nakazawa, Yasuo [Showa Univ., Tokyo (Japan). Hospital; Umeda, Hirotaka; Takenaka, Haruki; Shinozuka, Akira

    2001-09-01

    The purpose of this study was to estimate lung regional function using Xe-133 dynamic SPECT. SPECT equipment with a dual camera was used. Fourteen rotation acquisitions were obtained beginning immediately after Xe-133 gas inhalation. The time activity curve of each pixel was obtained, and T{sub 1/2} of the washout phase was calculated and mapped. Residual radioactivity was evaluated. Adequate images could be obtained at 30 seconds per rotation even with the dual-camera system. Mapping of T{sub 1/2} allowed temporal changes on one image. Three-dimensional evaluation could be made on a SPECT system using our method. (author)

  11. Nonlinear optics in Xe-filled hollow-core PCF in high pressure and supercritical regimes

    CERN Document Server

    Azhar, M; Travers, J C; Russell, P St J

    2013-01-01

    Supercritical Xe at 293 K offers a Kerr nonlinearity that can exceed that of fused silica while being free of Raman scattering. It also has a much higher optical damage threshold and a transparency window that extends from the UV to the infrared. We report the observation of nonlinear phenomena, such as self-phase modulation, in hollow-core photonic crystal fiber filled with supercritical Xe. In the subcritical regime, intermodal four-wave-mixing resulted in the generation of UV light in the HE12 mode. The normal dispersion of the fiber at high pressures means that spectral broadening can clearly obtained without influence from soliton effects or material damage.

  12. Formation of a narrow baryon resonance with positive strangeness in K^+ collisions with Xe nuclei

    CERN Document Server

    Barmin, V V; Borisov, V S; Curceanu, C; Davidenko, G V; Dolgolenko, A G; Guaraldo, C; Kubantsev, M A; Larin, I F; Matveev, V A; Shebanov, V A; Shishov, N N; Sokolov, L I; Tumanov, G K; Verebryusov, V S

    2009-01-01

    The data on the charge-exchange reaction K^+Xe --> K^0 p Xe, obtained with the bubble chamber DIANA, are reanalyzed using increased statistics and updated selections. Our previous evidence for formation of a narrow pK^0 resonance with mass near 1538 MeV is confirmed and reinforced. The statistical significance of the signal reaches some 8\\sigma (6\\sigma) when estimated as S/\\sqrt{B} (S/\\sqrt{B+S}). The mass and intrinsic width of the \\Theta^+ baryon are measured as m = (1538+-2) MeV and \\Gamma = (0.39+-0.10) MeV.

  13. Observation of Two-Neutrino Double-Beta Decay in Xe-136 with EXO-200

    Energy Technology Data Exchange (ETDEWEB)

    Ackerman, N.; /SLAC; Aharmim, B.; /Laurentian U.; Auger, M.; /Bern U.; Auty, D.J.; /Alabama U.; Barbeau, P.S.; Barry, K.; Bartoszek, L.; /Stanford U., Phys. Dept.; Beauchamp, E.; /Laurentian U.; Belov, V.; /Moscow, ITEP; Benitez-Medina, C.; /Colorado State U.; Breidenbach, M.; /SLAC; Burenkov, A.; /Moscow, ITEP; Cleveland, B.; /Laurentian U.; Conley, R.; Conti, E.; /SLAC; Cook, J.; /Massachusetts U., Amherst; Cook, S.; /Colorado State U.; Coppens, A.; /Carleton U.; Counts, I.; /Stanford U., Phys. Dept.; Craddock, W.; /SLAC; Daniels, T.; /Massachusetts U., Amherst /Moscow, ITEP /Maryland U. /Stanford U., Phys. Dept. /Alabama U. /Maryland U. /Moscow, ITEP /Stanford U., Phys. Dept. /Laurentian U. /Carleton U. /Colorado State U. /Laurentian U. /Munich, Tech. U. /Bern U. /SLAC /Bern U. /Carleton U. /Stanford U., Phys. Dept. /Carleton U. /Maryland U. /Colorado State U. /SLAC /Carleton U. /SLAC /Alabama U. /SLAC /Moscow, ITEP /Indiana U. /Stanford U., Phys. Dept. /Moscow, ITEP /Stanford U., Phys. Dept. /Massachusetts U., Amherst /Seoul U. /Carleton U. /Stanford U., Phys. Dept.; /more authors..

    2012-09-14

    We report the observation of two-neutrino double-beta decay in {sup 136}Xe with T{sub 1/2} = 2.11 {+-} 0.04(stat) {+-} 0.21(syst) x 10{sup 21} yr. This second-order process, predicted by the standard model, has been observed for several nuclei but not for {sup 136}Xe. The observed decay rate provides new input to matrix element calculations and to the search for the more interesting neutrinoless double-beta decay, the most sensitive probe for the existence of Majorana particles and the measurement of the neutrino mass scale.

  14. Observation of Two-Neutrino Double-Beta Decay in Xe-136 with EXO-200

    CERN Document Server

    Ackerman, N; Auger, M; Auty, D J; Barbeau, P S; Barry, K; Bartoszek, L; Beauchamp, E; Belov, V; Benitez-Medina, C; Breidenbach, M; Burenkov, A; Cleveland, B; Conley, R; Conti, E; Cook, J; Cook, S; Coppens, A; Counts, I; Craddock, W; Daniels, T; Danilov, M V; Davis, C G; Davis, J; deVoe, R; Djurcic, Z; Dobi, A; Dolgolenko, A G; Dolinski, M J; Donato, K; Fairbank, W; Farine, J; Fierlinger, P; Franco, D; Freytag, D; Giroux, G; Gornea, R; Graham, K; Gratta, G; Green, M P; Hagemann, C; Hall, C; Hall, K; Haller, G; Hargrove, C; Herbst, R; Herrin, S; Hodgson, J; Hughes, M; Johnson, A; Karelin, A; Kaufman, L J; Koffas, T; Kuchenkov, A; Kumar, A; Kumar, K S; Leonard, D S; Leonard, F; LePort, F; Mackay, D; MacLellan, R; Marino, M; Martin, Y; Mong, B; Diez, M Montero; Morgan, P; Muller, A R; Neilson, R; Nelson, R; Odian, A; O'Sullivan, K; Ouellet, C; Piepke, A; Pocar, A; Prescott, C Y; Pushkin, K; Rivas, A; Rollin, E; Rowson, P C; Russell, J J; Sabourov, A; Sinclair, D; Skarpaas, K; Slutsky, S; Stekhanov, V; Strickland, V; Swift, M; Tosi, D; Twelker, K; Vogel, P; Vuilleumier, J -L; Vuilleumier, J -M; Waite, A; Waldman, S; Walton, T; Wamba, K; Weber, M; Wichoski, U; Wodin, J; Wright, J D; Yang, L; Yen, Y -R; Zeldovich, O Ya

    2011-01-01

    We report the observation of two-neutrino double-beta decay in Xe-136 with T_1/2 = 2.11 +- 0.04 (stat.) +- 0.21 (sys.) x 10^21 yr. This second order process, predicted by the Standard Model, has been observed for several nuclei but not for Xe-136. The observed decay rate provides new input to matrix element calculations and to the search for the more interesting neutrino-less double-beta decay, the most sensitive probe for the existence of Majorana particles and the measurement of the neutrino mass scale.

  15. Search for electric dipole moment in 129Xe atom using active nuclear spin maser

    Directory of Open Access Journals (Sweden)

    Ichikawa Y.

    2014-03-01

    Full Text Available An experimental search for an electric dipole moment in the diamagnetic atom 129Xe is in progress through the precision measurement of spin precession frequency using an active nuclear spin maser. A 3He comagnetometer has been incorporated into the active spin maser system in order to cancel out the long-term drifts in the external magnetic field. Also, a double-cell geometry has been adopted in order to suppress the frequency shifts due to interaction with polarized Rb atoms. The first EDM measurement with the 129Xe active spin maser and the 3He comagnetometer has been conducted.

  16. Dynamics of surface plasma generation by the microsecond emission of the XeF laser

    Science.gov (United States)

    Min'ko, L. Ia.; Chumakov, A. N.; Efremov, V. V.; Bakeev, A. A.; Nikolashina, L. I.; Prokopenko, N. V.; Sorokin, V. A.

    1991-06-01

    The dynamics of surface plasma generation by the microsecond emission of the XeF laser and the interaction of the ultraviolet emission with absorbent materials and the plasma at atmospheric pressure were investigated experimentally. The XeF laser used in the experiments operated at a wavelength of 0.35 micron, with a maximum emergy of 30 J and a pulse width of 3 microsec; the target materials included aluminum, bismuth, and graphite. The experimental results are presented in graphic form and compared with theoretical data.

  17. A novel Cs-(129)Xe atomic spin gyroscope with closed-loop Faraday modulation.

    Science.gov (United States)

    Fang, Jiancheng; Wan, Shuangai; Qin, Jie; Zhang, Chen; Quan, Wei; Yuan, Heng; Dong, Haifeng

    2013-08-01

    We report a novel Cs-(129)Xe atomic spin gyroscope (ASG) with closed-loop Faraday modulation method. This ASG requires approximately 30 min to start-up and 110 °C to operate. A closed-loop Faraday modulation method for measurement of the optical rotation was used in this ASG. This method uses an additional Faraday modulator to suppress the laser intensity fluctuation and Faraday modulator thermal induced fluctuation. We theoretically and experimentally validate this method in the Cs-(129)Xe ASG and achieved a bias stability of approximately 3.25 °∕h.

  18. Determination of adipose tissue blood flow with local 133Xe clearance. Evaluation of a new labelling technique

    DEFF Research Database (Denmark)

    Simonsen, Lene; Enevoldsen, Lotte Hahn; Bülow, Jens

    2003-01-01

    Adipose tissue blood flow was measured in six healthy, non-obese subjects with the xenon wash-out technique after labelling of the tissue by either injection of 133Xe dissolved in isotonic sodium chloride (water depot) or injection of 133Xe in gas form (gas depot). The wash-out rates were registe...

  19. PF-AR upgrading project

    CERN Document Server

    Kasuga, T

    2002-01-01

    The upgrading project of the dedicated pulse X-ray source PF-AR has been completed by the end of the 2001 fiscal year. Machine commissioning exclusively using the injector linac was successfully accomplished in the beginning of January 2002. After fine tuning of the machine and cleaning of the vacuum system with the beams from the middle of January to the middle of March, routine operation for users has begun in April. The historical details, commissioning and results of the project are reported. (author)

  20. Laser generation of XeCl exciplex molecules in a longitudinal repetitively pulsed discharge in a Xe – CsCl mixture

    Energy Technology Data Exchange (ETDEWEB)

    Boichenko, A M [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Klenovskii, M S [National Research Tomsk Polytechnic University, Tomsk (Russian Federation)

    2015-12-31

    By using the previously developed kinetic model, we have carried out simulations to study the possibility of laser generation of XeCl exciplex molecules in the working medium based on a mixture of Xe with CsCl vapours, excited by a longitudinal repetitively pulsed discharge. The formation mechanism of exciplex molecules in this mixture is fundamentally different from the formation mechanisms in the traditional mixtures of exciplex lasers. The conditions that make the laser generation possible are discussed. For these conditions, with allowance for available specific experimental conditions of the repetitively pulsed discharge excitation, we have obtained the calculated dependences of the power and efficiency of generation on the reflectivity of mirrors in a laser cavity. (active media)

  1. Deformation driving intruder orbitals in {sup 77}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Sylvan, G.N.; Doering, J.; Johns, G.D.; Tabor, S.L. [Department of Physics, Florida State University, Tallahassee, Florida 32306 (United States); Gross, C.J. [ORISE, Oak Ridge Associated Universities, Oak Ridge, Tennessee 37831 (United States)]|[Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Baktash, C.; Jin, H.; Stracener, D.W. [Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Hua, P.F.; Korolija, M.; LaFosse, D.R.; Sarantites, D.G. [Chemistry Department, Washington University, St. Louis, Missouri 63130 (United States); Cristancho, F.; Landulfo, E.; Saladin, J.X. [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Cederwall, B.; Lee, I.Y.; Macchiavelli, A.O.; Rathbun, W. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Vander Molen, A. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)

    1997-08-01

    High-spin states in {sup 77}Kr were identified via analysis of prompt {gamma}-{gamma} coincidences in the {sup 58}Ni({sup 29}Si,2{alpha}2p) reaction at 128 MeV at the Gammasphere facility. Evaporation channel selection was achieved using the 95 element Microball charged-particle detector. 27 new states and 42 new transitions were found. The positive-parity bands were confirmed and the {alpha}={minus}(1)/(2) band extended to (39)/(2){sup +}. The negative-parity signature pair was extended to (31)/(2){sup {minus}} and (37)/(2){sup {minus}}. Two new high-lying negative-parity bands were found extending from a state of spin I=(15)/(2) and energy 2.6 MeV to 17.4 MeV at I=((55)/(2)). The new bands appear highly deformed and become yrast at high spin. A three-quasiparticle structure based on deformation driving, low-K unique-parity and intruder orbitals is suggested for them. {copyright} {ital 1997} {ital The American Physical Society}

  2. Measurement of the attenuation length of argon scintillation light in the ArDM LAr TPC

    CERN Document Server

    Calvo, J; Crivelli, P; Daniel, M; DiLuise, S; Gendotti, A; Horikawa, S; Molina-Bueno, L; Montes, B; Mu, W; Murphy, S; Natterer, G; Ngyuen, K; Periale, L; Quan, Y; Radics, B; Regenfus, C; Romero, L; Rubbia, A; Santorelli, R; Sergiampietri, F; Viant, T; Wu, S

    2016-01-01

    We report on a measurement of the attenuation length for the scintillation light in the tonne size liquid argon target of the ArDM dark matter experiment. The data was recorded in the first underground operation of the experiment in single-phase operational mode. The results were achieved by comparing the light yield spectra from 39-Ar and 83m-Kr to a description of the ArDM setup with a model of full light ray tracing. A relatively low value close to 0.5 m was found for the attenuation length of the liquid argon bulk to its own scintillation light. We interpret this result as a presence of optically active impurities in the liquid argon which are not filtered by the installed purification systems. We also present analyses of the argon gas employed for the filling and discuss cross sections in the vacuum ultraviolet of various molecules in respect to purity requirements in the context of large liquid argon installations.

  3. Calibration of liquid argon and neon detectors with $^{83}Kr^m$

    CERN Document Server

    Lippincott, W H; Gastler, D; Kastens, L W; Kearns, E; McKinsey, D N; Nikkel, J A

    2009-01-01

    We report results from tests of $^{83}$Kr$^{\\mathrm{m}}$, as a calibration source in liquid argon and liquid neon. $^{83}$Kr$^{\\mathrm{m}}$ atoms are produced in the decay of $^{83}$Rb, and a clear $^{83}$Kr$^{\\mathrm{m}}$ scintillation peak at 41.5 keV appears in both liquids when filling our detector through a piece of zeolite coated with $^{83}$Rb. Based on this scintillation peak, we observe 6.0 photoelectrons/keV in liquid argon with a resolution of 6% ($\\sigma$/E) and 3.0 photoelectrons/keV in liquid neon with a resolution of 19% ($\\sigma$/E). The observed peak intensity subsequently decays with the $^{83}$Kr$^{\\mathrm{m}}$ half-life after stopping the fill, and we find evidence that the spatial location of $^{83}$Kr$^{\\mathrm{m}}$ atoms in the chamber can be resolved. $^{83}$Kr$^{\\mathrm{m}}$ will be a useful calibration source for liquid argon and neon dark matter and solar neutrino detectors.

  4. (83)Kr nuclear magnetic moment in terms of that of (3)He.

    Science.gov (United States)

    Makulski, Włodzimierz

    2014-08-01

    High resolution NMR spectroscopy was applied to precisely determine the (83)Kr nuclear magnetic dipole moment on the basis of new results available for nuclear magnetic shielding in krypton and helium-3 atoms. Small amounts of (3)He as the solutes and (83)Kr as the buffer gas were observed in (3)He and (83)Kr NMR spectra at the constant external field, B0 = 11.7578 T. In each case, the resonance frequencies (ν(He) and ν(Kr)) were linearly dependent on the density of gaseous solvent. The extrapolation of experimental points to the zero density of gaseous krypton allowed for the evaluation of both resonance frequencies free from intermolecular interactions. By combining these measurements with the recommended (83)Kr chemical shielding value, the nuclear magnetic moment could be determined with much better precision than ever before, μ((83)Kr) = -0.9707297(32)μN, with the improvement due to the greater accuracy of the spectral data.

  5. Discharge-current characteristics in UV-preionized Kr/He, F2/He gas-mixtures and KrF excimer laser gas. Shigaisen yobi denri Kr/He, F2/He kongo kitai hoden oyobi KrF laser reiki hoden no denryu tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, N.; Kawakami, H.; Yukimura, K. (Doshisha University, Kyoto (Japan))

    1992-08-15

    In order to study effects of Kr and F2 on discharge characteristics of KrF excimer laser gas, gap phenomena in Kr/He and F2/He gas-mixtures were observed and discharge current (I[sub d]) was measured. In the range where Kr concentration was over 10% in Kr/He gas, in which production of filamentation as well as glow discharge started, discontinuous change in I[sub d] in the second or third half cycle was observed. According to the results of experiments and model analyses, it was considered that the discontinuity of the current showed the transition point to filamentation. When F2 concentration was in the range between 0.1 and 0.3% in F2/He mixture gas, filamentation and arc with glow were observed. Sine-waveform I[sub d] ended in the first half cycle, and began to flow again after cessation or had almost constant current due to arc and others. When F2 was over 0.4%, only are discharge was observed. It was thus found that F2 has a large effect on discharge characteristics of KrF laser gas. 18 refs., 9 figs.

  6. The investigation of excimer XeF * (~354 nm) emission efficiency at excitation Xe/SF 6 mixture by barrier discharge

    Science.gov (United States)

    Pikulev, A. A.; Tsvetkov, V. M.

    2008-01-01

    The results of investigations of dielectric barrier discharges parameters and UV-emission of Xe/SF 6 (50:1) mixture related to the pressure and the distance between electrodes are presented. The basic source of UV-emission in Xe/SF 6 mixture is XeF * excimer, whose emission band center is positioned at 354 nm. The mixture pressure was varied in the range from 40 to 180 Torr, and the distance between electrodes changed in range from 3 to 11 mm. The distance between the electrodes and the gas pressure were selected out so that pd-product should be constant. The experiments conducted display that for pd = const in the pressure range of 70-180 Torr there are some regularities which are partly similar to the scaling laws of gas discharge, namely: the current density ~ const; the power dissipated by the discharge ~ 1/p 0.3; UV emission power ~ 1/p; the efficiency of lamp ~ 1/p 0.8; the current pulse duration ~ 1/p 0.3. The highest efficiency (6-8%) was reached for 30-50 Torr gas pressure.

  7. Characterization of the cytochrome P450 enzymes involved in the metabolism of a new cardioprotective agent KR-33028.

    Science.gov (United States)

    Kim, Hyojin; Yoon, Yune-Jung; Kim, Hyunmi; Kang, Suil; Cheon, Hyae Gyeong; Yoo, Sung-Eun; Shin, Jae-Gook; Liu, Kwang-Hyeon

    2006-10-10

    KR-33028 (N-[4-cyano-benzo[b]thiophene-2-carbonyl]guanidine) is a new cardioprotective agent for preventing ischemia-reperfusion injury. This study was performed to characterize the cytochrome P450 (CYP) enzymes that are involved in the metabolism of KR-33028. Hydroxylation (5-hydroxy- and 7-hydroxy-KR-33028) is major pathways for the metabolism of KR-33028 in human liver microsomes. Among the nine c-DNA expressed CYP isoforms tested, KR-33028 was 5-hydroxylated by CYP3A4 and 7-hydroxylated by CYP1A2, CYP3A4, and CYP2C19. These findings were supported by the combination of chemical inhibition studies in human liver microsomes and correlation analysis. Furafylline and ketoconazole potently inhibited hydroxylation of KR-33028 in human liver microsomes. Correlation analysis between the known CYP enzyme activities and the rates of the formation of 5-hydroxy- and 7-hydroxy-KR-33028 in the 16 human liver microsomes has showed significant correlations with CYP3A4-mediated midazolam 1'-hydroxylation and CYP1A2-mediated phenacetin O-deethylation, respectively. A 7-hydroxy-KR-33028 formation is also weakly correlated with CYP3A4-mediated midazolam 1'-hydroxylation. The kinetics of the major biotransformation of KR-33028 were studied: CYP3A4 mediated the formation of 5-hydroxy-KR-33028 from KR-33028 with Cl(int)=0.22microl/min/pmol CYP. The intrinsic clearance for 7-hydroxy-KR-33028 formation by CYP1A2, CYP2C19, and CYP3A4 were 0.26, 0.19, and 0.03microl/min/pmol CYP, respectively. Taken together, these results provide evidence that CYP3A4 and CYP1A2 are the major isoforms responsible for the hydroxy metabolites formation from KR-33028.

  8. Interpretation of discordant 40Ar/39Ar age-spectra of mesozoic tholeiites from antarctica

    Science.gov (United States)

    Fleck, R.J.; Sutter, J.F.; Elliot, D.H.

    1977-01-01

    Conventional K-Ar ages of tholeiitic basalts of the Ferrar Group in the central Transantarctic Mountains indicate significant loss of radiogenic 40Ar from this unit over much of its outcrop area. Argon loss varies inversely with amount of devitrified matrix in the basalts, which have not been thermally or tectonically disturbed since extrusion. 40Ar/19Ar age-spectra of these tholeiites are generally discordant and indicate significant inhomogeneity in the distribution of radiogenic 40Ar with respect to 39Ar, but are distinctly different from release patterns of thermally disturbed samples. Amounts of argon redistribution vary directly with amounts of devitrification and are reflected in progressive modification of the age spectra. A model of redistribution of radiogenic 40Ar by devitrification of originally glassy matrix is suggested that is consistent with disturbance of the conventional K-Ar systematics as well as the 40Ar/39Ar age-spectra. Samples with substantial redistribution but minor loss of radiogenic argon yield age spectra whose apparent ages decrease from low-temperature to high-temperature steps, similar to those reported for some lunar basalts, breccias, and soils. Modification of all the age spectra is attributed to redistribution of radiogenic 40Ar during progressive devitrification, although 39Ar-recoil effects suggested by Turner and Cadogan (1974) may be a factor in some cases. Where devitrification involves most potassium sites within the basalt, 40Ar/39Ar age-plateaux may be formed that have no geologic significance. ?? 1977.

  9. Dmitri Krõmov : jesli tõ ne metshtajesh otkrõt Ameriku, tõ ne morjak! / Dmitri Krõmov ; interv. Boris Tuch

    Index Scriptorium Estoniae

    Krõmov, Dmitri

    2007-01-01

    Vene teatrikunstnik, lavastaja endast, oma isast Anatoli Efrosest, lavastamise juurde jõudmisest, teaterstuudio juhi Anatoli Vassiljevi Venemaalt lahkumise põhjustest. Teatrifestivalil "Talveöö unenägu 2006" oli D. Krõmov oma lavastusega "Söör Vantes. Donki Hot"

  10. A kinetic model of the electron-beam-pumped XeCl laser active medium

    Energy Technology Data Exchange (ETDEWEB)

    Boichenko, A.M.; Derzhiev, V.I.; Zhidkov, A.G.; Iakovlenko, S.I. (Institut Obshchei Fiziki, Moscow (USSR))

    1989-02-01

    Kinetic models are developed for XeCl laser active media in different buffer gases (helium, neon, and argon) pumped by an electron beam. In the calculations of the generation characteristics, allowance is made for the effect of the cavity field on the photoinduced transitions. The numerical results on the efficiency are in good agreement with experiments on electron beams. 17 refs.

  11. Color functional images of the cerebral blood flow. [/sup 133/Xe

    Energy Technology Data Exchange (ETDEWEB)

    Toyama, H.; Iio, M.; Iisaka, J.; Chiba, K.; Yamada, H.; Matsui, K.; Hoshi, Y.; Fuse, M.

    1976-11-01

    Functional gamma imaging, in color, was established for regional cerebral blood flow (rCBF) using /sup 133/Xe. During 10 min after intracarotid injection of /sup 133/Xe in saline, 60 picture frames of the /sup 133/Xe clearance curve for the entire hemisphere were obtained. After nine-point smoothing, the rCBF for each of the 4,096 picture elements was calculated by two methods: the half-time method and the height-over-area method. Both the /sup 133/Xe clearance half-times and the calculated CBF values were displayed, using 13 steps of color, as functional CBF images of the brain. Images of peak count and total count were also displayed on the same frame of the color television. Forty-six studies, performed on 37 patients with various cerebral disorders, were divided into two types: diffuse and focal. In the diffuse type, a decrease in CBF was noted in cases of normal-pressure hydrocephalus; successful ventriculoperitoneal shunt operations were followed by recovery of CBF. Occlusion of the middle cerebral artery showed up as a wedge-shaped area of decreased CBF, even when the conventional brain scan looked normal. Increased perfusion to a tumor was frequently associated with decreased CBF in the rest of the lateral hemisphere; such a decrease could be improved by surgical removal of the tumor.

  12. Study of collisions of {sup 136}Xe + {sup 198}Pt for the KEK isotope separator

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Y.X., E-mail: yutaka.watanabe@kek.jp [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Hirayama, Y.; Imai, N.; Ishiyama, H.; Jeong, S.C.; Miyatake, H. [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Clement, E.; France, G. de; Navin, A.; Rejmund, M.; Schmitt, C. [Grand Accélérateur National d’Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 05 (France); Pollarolo, G. [Dipartimento di Fisica Teorica, Università di Torino, Via Pietro Giuria 1, 10125 Torino (Italy); Corradi, L.; Fioretto, E. [Laboratori Nazionali di Legnaro dell’INFN, Via Romea 4, 35020 Legnaro (Italy); Montanari, D. [Università di Padova, Via 8 Febbraio, 2-35122 Padova (Italy); Choi, S.H.; Kim, Y.H.; Song, J.S. [Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Niikura, M.; Suzuki, D. [Institut de Physique Nucléaire (IPN), IN2P3-CNRS, Université Paris-Sud 11, F-91406 Orsay Cedex (France); and others

    2013-12-15

    Highlights: • {sup 136}Xe + {sup 198}Pt shows a comparable contribution of proton pick-up and stripping. • Proton stripping channels in {sup 136}Xe + {sup 198}Pt show enhanced cross sections. • Mass distributions of proton stripping channels in {sup 136}Xe + {sup 198}Pt shift to heavy side. -- Abstract: Multinucleon transfer reactions between two heavy ions are an important tool for production and investigation of exotic neutron-rich nuclei, which are difficult to access by other methods. The {sup 136}Xe + {sup 198}Pt system is a candidate to efficiently produce neutron-rich nuclei around the neutron magic number N=126 for the KEK isotope separation project. In order to confirm this, measurements of the production cross sections with the large acceptance magnetic spectrometer VAMOS++ and de-excitation gamma rays from target-like fragments using the high efficiency germanium array EXOGAM at GANIL are reported. The measured isotopic distributions of the projectile-like fragments are compared with GRAZING calculations. The proton stripping channels show rough agreements between measurements and calculations. For the proton pick-up channels, the measured distributions are shifted toward the heavier masses and show enhanced cross sections in transfers of two or more protons.

  13. Regional cerebral blood flow assessed by 133Xe inhalation and emission tomography

    DEFF Research Database (Denmark)

    Shirahata, N; Henriksen, L; Vorstrup, S

    1985-01-01

    Regional cerebral blood flow (rCBF) in the cerebral hemispheres and the cerebellum was measured by single photon emission computed tomography with inhalation of 133Xe in 39 normal volunteers at test. The goal of this study was to assess the normal flow pattern and its variations. Five parallel...

  14. Development of NCLR's 1-kW XeCl laser

    NARCIS (Netherlands)

    Timmermans, John; Hofstra, Ramon; Couperus, Jacob; Kleijhorst, Richard; Prins, Henk; Oude Meijers, Gerard; Heel, van Huub

    2000-01-01

    For several years NCLR is working on a 1 kW, 1 kHz XeCl laser. Improvement of the beam quality at high power levels enabled us to do large-scale application experiments and industrial applications become feasible. The base for the good beam quality is a homogeneous discharge. It starts with a smooth

  15. Beam divergence studies on a long-pulse XeCl excimer laser

    NARCIS (Netherlands)

    Hofstra, R.M.; Goor, van F.A.; Witteman, W.J.; Letardi, Tommaso; Weber, Horst

    1996-01-01

    The focusability of a long pulse XeCl excimer laser has been improved using confocal positive branch unstable resonators where the outcoupling is done through the convex mirror. For the outcoupler different reflectivity profiles are used. A near diffraction limited output beam is obtained from hard

  16. High-repetition-rate XeCl waveguide laser without gas flow

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, C.P.; Gordon C. III; Moutoulas, C.; Feldman, B.J.

    1987-03-01

    Operation of a microwave discharge XeCl laser at pulse-repetition rates extending to 8 kHz without flow of the laser gas is reported. Present limits on pulse-repetition rate appear to be imposed by thermally induced refractive-index gradients.

  17. Radiopharmacology of inhaled [sup 133]Xe in skeletal sites containing deposits of Gaucher cells

    Energy Technology Data Exchange (ETDEWEB)

    Castronovo, F.P. Jr. (Brigham and Women' s Hospital, Boston, MA (United States) Harvard Medical School, Boston, MA (United States)); McKusick, K.A.; Doppelt, S.H. (Massachusetts General Hospital, Boston, MA (United States) Harvard Medical School, Boston, MA (United States)); Barton, N.W. (National Insts. of Health, Bethesda, MD (United States))

    1993-07-01

    Gaucher's disease is a lysomal storage disease in which cells of the reticuloendothelial system accumulate the lipid glucocerebroside. It is characterized by slowly progressive visceral and osseous involvement. One of the latter manifestations includes lipid infiltration of bone marrow. We monitored the rate of the inhaled [sup 133]Xe uptake and wash-out over diseased and normal metaphyseal and epiphyseal areas of the knee. Twenty-two patients (15 adults, 7 children) with various degrees of previously diagnosed Gaucher's disease were positioned supine under a [gamma]-camera interfaced to a computer system. All patients rebreathed [sup 133]Xe gas from a closed system for 10 min followed by 14 min of wash-out. Digitized images of the lung, liver, spleen, bony sites and soft tissue were obtained at 1 min intervals during the wash-in and wash-out phases. Counts for each ROI were normalized per 100 pixels and plotted as a function (time). Maximum uptake was also calculated by relating the counts/ROI/100 pixels to the 10 min integrated lung count during equilibrium (the administered ''dose''). There was essentially no [sup 133]Xe uptake in liver and spleen involved with Gaucher's disease. Monophasic uptake and biphasic wash-out curves were observed in the limited investigative population. Gaucher deposits released the [sup 133]Xe at a greater rate relative to soft tissue. (Author).

  18. A Molecular Imaging Approach to Mercury Sensing Based on Hyperpolarized (129)Xe Molecular Clamp Probe.

    Science.gov (United States)

    Guo, Qianni; Zeng, Qingbin; Jiang, Weiping; Zhang, Xiaoxiao; Luo, Qing; Zhang, Xu; Bouchard, Louis-S; Liu, Maili; Zhou, Xin

    2016-03-14

    Mercury pollution, in the form of mercury ions (Hg(2+)), is a major health and environmental hazard. Commonly used sensors are invasive and limited to point measurements. Fluorescence-based sensors do not provide depth resolution needed to image spatial distributions. Herein we report a novel sensor capable of yielding spatial distributions by MRI using hyperpolarized (129)Xe. A molecular clamp probe was developed consisting of dipyrrolylquinoxaline (DPQ) derivatives and twocryptophane-A cages. The DPQ derivatives act as cation receptors whereas cryptophane-A acts as a suitable host molecule for xenon. When the DPQ moiety interacts with mercury ions, the molecular clamp closes on the ion. Due to overlap of the electron clouds of the two cryptophane-A cages, the shielding effect on the encapsulated Xe becomes important. This leads to an upfield change of the chemical shift of the encapsulated Xe. This sensor exhibits good selectivity and sensitivity toward the mercury ion. This mercury-activated hyperpolarized (129)Xe-based chemosensor is a new concept method for monitoring Hg(2+) ion distributions by MRI.

  19. Pulse height measurements and electron attachment in drift chambers operated with Xe,CO2 mixtures

    CERN Document Server

    Andronic, A

    2003-01-01

    We present pulse height measurements in drift chambers operated with Xe,CO2 gas mixtures. We investigate the attachment of primary electrons on oxygen and SF6 contaminants in the detection gas. The measurements are compared with simulations of properties of drifting electrons. We present two methods to check the gas quality: gas chromatography and Fe55 pulse height measurements using monitor detectors.

  20. Evaluation of the Sysmex Xe-2100 hematology analyzer in hospital use.

    Science.gov (United States)

    Nakul-Aquaronne, Danièle; Sudaka-Sammarcelli, Isabelle; Ferrero-Vacher, Corinne; Starck, Benoit; Bayle, Jacques

    2003-01-01

    The Sysmex XE-2100 (Sysmex Corp. Kobe, Japan) is a latest-generation hematology analyzer. Its optical and electrical measuring technology is improved by the addition of flux cytometry, fluorescence, and differential lysis. Its analytical performance in terms of precision, reproducibility, linearity, carryover, and time stability was found to be entirely satisfactory. In addition, the results of 500 complete blood counts and differentials correlated perfectly with those obtained by the Coulter STKS (Beckman Coulter, Villapointe, France). The comparison of 500 leukocyte differential count results analyzed in parallel with optical microscopy and the XE-2100 were surprising, and favorable to the XE-2100. This analyzer provides the user with an undeniable feeling of security concerning its reliability in detecting and identifying anomalies in the automated leukocyte differential count. With a sensitivity of 96%, a negative predictive value (NPV) of 98%, and a false-negative (FN) rate of 4%, the XE-2100 has perhaps reached the technological limits for a machine performing morphological recognition of normal and pathological blood cells.

  1. Trapping of xenon in ice - Implications for the origin of the earth's noble gases

    Science.gov (United States)

    Wacker, J. F.; Anders, E.

    1984-01-01

    Although the earth's atmosphere contains Ne, Ar, and Kr in about C1,2-chondrite proportions, Xe is depleted about 20-fold. To test the suggestion that the 'missing' Xe is trapped in Antarctic ice, distribution coefficients for Xe in artifically formed frost at -20 to -60 C were measured, using Xe-127 tracer. The values are 0.098 + or - 0.004 cc STP/g atm for trapping and less than 5 cc STP/g atm for trapping plus adsorption. If these results are representative of natural ice, then the Antarctic ice cap contains less than 1 percent of the atmospheric Xe inventory, or not greater than about 0.001 the amount needed for a C1,2-chondrite pattern. Two possibilities remain for the 'missing' Xe, both on the premise that the earth's noble gases, along with other volatiles, came from chondritic material: (1) xenon is preferentially retained in the mantle and lower crust, due to the strong affinity of Xe for clean silicate surfaces and amorphous carbon; and (2) the source material of the earth's volatiles had high, relatively unfractionated, Ar/Xe and Kr/Xe ratios, like the non-carbonaceous noble gas carriers in C3O and E-chondrites.

  2. KrF-excimer laser pretreatment and metallization of polymers

    Science.gov (United States)

    Weichenhain, R.; Wesner, D. A.; Pfleging, W.; Horn, H.; Kreutz, E. W.

    1997-02-01

    Metal film adhesion to polymers can be improved by pretreatment with UV-laser radiation before metal deposition. Chemical changes associated with irradiation are investigated for polyimide (PI) and polybutylene terephthalate (PBT) surfaces. Irradiated surfaces are coated with aluminum films ≤10 nm in thickness, enabling the effects of irradiation on the metal/polymer interface to be studied. Irradiation is done in air with KrF-excimer laser radiation (λ=248 nm) at fluences per pulse ≤600 mJ/cm2. The threshold fluence εt for material removal is determined by profilometry measurements of etched features, and the chemical properties of the polymer and the metal/polymer interface are studied with X-ray photoelectron spectroscopy (XPS). Aluminum films are thermally evaporated in situ in the XPS spectrometer. Irradiation of PI at fluences near εt (41 mJ/cm2) results in loss of oxygen and opening of the imide ring, resulting in doubly bonded nitrogen species. After evaporation of aluminum the carbonyl (CO) C1s XPS signal is reduced in intensity, and both Al0 and Al3+ are found, the latter being located at the interface. In comparison to unirradiated areas, irradiated areas have more aluminum in total and a higher proportion of interfacial Al3+ species, indicating an increase in the concentration of metal binding sites. Although for PBT the O to C ratio also decreases with irradiation at fluences near εt (38 mJ/cm2), changes in the amounts of Al0 or Al3+ for irradiated areas in comparison to unirradiated areas are much smaller than for PI and consist mainly of a slight enhancement of Al0 for films deposited on irradiated surfaces.

  3. X-Ray and Extreme Ultraviolet Emission from Small-Sized Kr Clusters Irradiated by 150-fs Laser Pulses

    Institute of Scientific and Technical Information of China (English)

    王骐; 程元丽; 赵永蓬; 夏元钦; 陈建新; 肖亦凡

    2003-01-01

    x-ray and extreme ultraviolet (EUV) emission from Kr clusters irradiated by 150-fs laser pulses at the peak laser intensity of 5×1015W/cm2 was experimentally investigated. Strong transitions (10nm-13nm) from Kr X and Kr 1X were observed and some spectral lines from Kr ⅩⅢ and Kr ⅩⅣ, which have been predicted to be not produced by optical-field-ionization at the laser intensity used, also appeared. The laser energy absorption and the intensity of x-ray emission started to grow remarkably above the backing pressure of 0.5 MPa and to decrease at the backing pressure of 3 MPa. It is suggested that an optimum backing pressure may exist for Kr clusters heated by 150 fs laser pulses at a certain laser intensity to produce x-ray emission.

  4. Ars grammatica de Dionisio Tracio

    Directory of Open Access Journals (Sweden)

    Beltrán Jorge Enrique

    2003-06-01

    Full Text Available

    Ars Grammatica de Dionisio Tracio (170-90 a. C fue la primera gramática griega que se escribió. Su contenido y método fueron modelos que siguieron las gramáticas escolares posteriores. La versión española que se presenta ahora responde a la necesidad que se tenía en nuestro medio de una traducción completa de este texto. Finalmente, se acompaña la traducción de una introducción y de abundantes notas, en un intento por hacerla comprensible para el hablante del español, no necesariamente conocedor de la lengua griega.

  5. Measurement of fusion excitation functions in the system {sup 78}Kr + {sup 100}Mo

    Energy Technology Data Exchange (ETDEWEB)

    Rehm, K.E.; Jiang, C.L.; Esbensen, H. [and others

    1995-08-01

    Earlier measurements of fusion reactions involving {sup 78}Kr and {sup 100}Mo projectiles and Ni-targets showed surprisingly large fusion yields at low energies which could not be explained by coupled-channels calculations. The main difference to similar measurements involving the neighboring {sup 86}Kr and {sup 92}Mo isotopes was the different slope of the excitation functions at sub-barrier energies. An analysis of a variety of experiments showed a correlation between the nuclear structure and the slope of the excitation functions, with the {open_quotes}soft{close_quotes} transitional nuclei ({sup 78}Kr, {sup 100}Mo) exhibiting shallower slopes than the {open_quotes}stiff{close_quotes} nuclei ({sup 86}Kr, {sup 92}Mo) measured at the same energies with respect to the barrier. In this experiment we studied the fusion excitation function involving two transitional nuclei {sup 78}Kr + {sup 100}Mo. The measurements were performed with {sup 78}Kr beams from the ECR source at energies between 285-370 MeV. Separation of the evaporation nucleus from the elastically scattered particles was achieved by measuring time-of-flight and magnetic rigidity in the gas-filled spectrograph. The data were completely analyzed. A comparison of the cross sections with measurements for the system {sup 86}Kr + {sup 92}Mo populating the same compound nucleus {sup 178}Pt. It shows good agreement at the highest energies, but quite different falloffs of the excitation functions toward lower energies. Coupled-channels calculations, including multi-phonon excitation for the two systems, are being performed.

  6. Antiviral activity of KR-23502 targeting nuclear export of influenza B virus ribonucleoproteins.

    Science.gov (United States)

    Jang, Yejin; Lee, Hye Won; Shin, Jin Soo; Go, Yun Young; Kim, Chonsaeng; Shin, Daeho; Malpani, Yashwardhan; Han, Soo Bong; Jung, Young-Sik; Kim, Meehyein

    2016-10-01

    The spiro compound 5,6-dimethyl-3H,3'H-spiro(benzofuran-2,1'-isobenzofuran)-3,3'-dione (KR-23502) has antiviral activity against influenza A and more potently B viruses. The aim of this study is to elucidate its mechanism of action. Subcellular localization and time-course expression of influenza B viral proteins, nucleoprotein (NP) and matrix protein 1 (M1), showed that KR-23502 reduced their amounts within 5 h post-infection. Early steps of virus life cycle, including virus entry, nuclear localization of NP and viral RNA-dependent RNA replication, were not affected by KR-23502. Instead it interrupted a later event corresponding to nuclear export of NP and M1 proteins. Delivery of viral ribonucleoprotein (vRNP)-M1 complex has been known to be mediated by the viral nuclear export protein (NEP) through interaction with cellular chromosomal maintenance 1 (CRM1) protein. In this study, we experimentally demonstrated that the compound targets the nuclear export of vRNP. Moreover, a single mutation (aspartate to glycine) at amino acid position 54 in M1 [M1(D54G)] was detected after 18 passages in the presence of KR-23502 with a 2-fold increase in 50% effective concentration indicating that this compound has a relatively high genetic barrier to resistance. Interestingly, it was observed that proteasome-mediated degradation of M1(D54G) was attenuated by KR-23502. In conclusion, we suggest that KR-23502 shows its anti-influenza activity by downregulating NEP/CRM1-mediated nuclear export of influenza vRNP and M1. KR-23502 provides a core chemical skeleton for further structure-based design of novel antivirals against influenza viruses.

  7. Photo-ignition process of multiwall carbon nanotubes and ferrocene by continuous wave Xe lamp illumination

    Science.gov (United States)

    Primiceri, Patrizio; Longo, Daniele; Strafella, Luciano; Carlucci, Paolo; Lomascolo, Mauro; Cretì, Arianna; Mele, Giuseppe

    2017-01-01

    Summary This work aims to investigate and characterize the photo-ignition phenomenon of MWCNT/ferrocene mixtures by using a continuous wave (CW) xenon (Xe) light source, in order to find the power ignition threshold by employing a different type of light source as was used in previous research (i.e., pulsed Xe lamp). The experimental photo-ignition tests were carried out by varying the weight ratio of the used mixtures, luminous power, and wavelength range of the incident Xe light by using selective optical filters. For a better explanation of the photo-induced ignition process, the absorption spectra of MWCNT/ferrocene mixtures and ferrocene only were obtained. The experimental results show that the luminous power (related to the entire spectrum of the Xe lamp) needed to trigger the ignition of MWCNT/ferrocene mixtures decreases with increasing metal nanoparticles content according to previously published results when using a different type of light source (i.e., pulsed vs CW Xe light source). Furthermore, less light power is required to trigger photo-ignition when moving towards the ultraviolet (UV) region. This is in agreement with the measured absorption spectra, which present higher absorption values in the UV–vis region for both MWCNT/ferrocene mixtures and ferrocene only diluted in toluene. Finally, a chemo-physical interpretation of the ignition phenomenon is proposed whereby ferrocene photo-excitation, due to photon absorption, produces ferrocene itself in its excited form and is thus capable of promoting electron transfer to MWCNTs. In this way, the resulting radical species, FeCp2+∙ and MWCNT−, easily react with oxygen giving rise to the ignition of MWCNT/ferrocene samples.

  8. 40Ar/39Ar Interlaboratory Calibration into the Holocene.

    Science.gov (United States)

    Heizler, M. T.; Jicha, B.; Koppers, A. A. P.; Miggins, D. P.

    2015-12-01

    Advances in 40Ar/39Ar analytical precision for very young rocks requires collaborative efforts amongst argon geochronology labs to demonstrate age reproducibility commensurate with high precision. NM Tech (NMT), the University of Wisconsin (UW) and Oregon State University (OSU) have each dated Quaternary flux monitor standard AC-2 sanidine (~1.185 Ma), a blind sanidine described as being 50-100 ka (BS) and sanidine from the Qixiangshan (QIX) flow (~10 ka), Changbaishan volcano, China. The samples were irradiated in a single package with FC-2 sanidine (28.201 Ma) as the flux monitor and the irradiated material was distributed amongst the labs. Heizler was present during analysis at both OSU and UW and Jicha attended OSU during analysis. Physical presence was key towards gaining understanding of individual protocols and prompted valuable discussions. Analyses were carried out on single crystals using total fusion and/or step heating approaches. Age agreement was achieved within 2s uncertainty that ranged between (0.03-0.3%, 0.13-0.37% and 1.8-2.6%) for AC-2, BS and QIX, respectively. Each lab found AC-2 to vary somewhat beyond a normal distribution and to yield an age relative to FC-2 of ~1.185 Ma that is ~1.3% (~5-10 sigma) lower than some published estimates. A key cause of the variation between this study and previous results may be variable gas pressure equilibration times between extraction line and mass spectrometer coupled with variable choices to estimate time zero by other laboratories. The majority of our efforts concentrated on the QIX sanidine where prior data obtained by our labs revealed a factor of two spread in age (~11 and 23 ka) based on experiments carried out by total fusion and bulk incremental heating. By conducting single crystal age spectrum analysis we were able to mitigate effects of melt inclusion hosted excess argon and xenocrystic contamination towards obtaining analytical agreement with apparent ages near 10 ka. However, philosophical

  9. Production of {sup 125}I from amorphous films of Si doped with {sup 124}Xe and evaluation of its potential use in brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Leal, Alexandre S., E-mail: asleal@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Viana, Gustavo A., E-mail: gviana@eletronuclear.gov.br [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Instituto de Fisica Gleb Wataghin; Siqueira, Paulo T.D.; Saiki, Mitiko, E-mail: mitiko@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    This work describes the simulation of a new material that can be used in the brachytherapy treatment. The material consists of xenon-incorporated amorphous silicon (Xe@a-Si). The irradiated {sup 124}Xe atoms of the samples are converted into {sup 125}Xe, according to the reaction: {sup 124}Xe (n,γ) {sup 125}Xe that, in turn, decays to the radioisotope {sup 125}I. A set of simulations performed using the MCNP5 code, shows that, in principle, the material proposed can be used in the seed of brachytherapy in the clinical treatment. (author)

  10. Bacterial spore detection and analysis using hyperpolarized (129)Xe chemical exchange saturation transfer (Hyper-CEST) NMR.

    Science.gov (United States)

    Bai, Yubin; Wang, Yanfei; Goulian, Mark; Driks, Adam; Dmochowski, Ivan J

    2014-08-01

    Previously, we reported hyperpolarized (129)Xe chemical exchange saturation transfer (Hyper-CEST) NMR techniques for the ultrasensitive (i.e., 1 picomolar) detection of xenon host molecules known as cryptophane. Here, we demonstrate a more general role for Hyper-CEST NMR as a spectroscopic method for probing nanoporous structures, without the requirement for cryptophane or engineered xenon-binding sites. Hyper-CEST (129)Xe NMR spectroscopy was employed to detect Bacillus anthracis and Bacillus subtilis spores in solution, and interrogate the layers that comprise their structures. (129)Xe-spore samples were selectively irradiated with radiofrequency pulses; the depolarized (129)Xe returned to aqueous solution and depleted the (129)Xe-water signal, providing measurable contrast. Removal of the outermost spore layers in B. anthracis and B. subtilis (the exosporium and coat, respectively) enhanced (129)Xe exchange with the spore interior. Notably, the spores were invisible to hyperpolarized (129)Xe NMR direct detection methods, highlighting the lack of high-affinity xenon-binding sites, and the potential for extending Hyper-CEST NMR structural analysis to other biological and synthetic nanoporous structures.

  11. Xe distribution in amorphous SiO{sub 2} as a function of implantation and thermal annealing parameters

    Energy Technology Data Exchange (ETDEWEB)

    Naas, A., E-mail: abdelkrim_naas@yahoo.fr [Conditions Extrêmes et Matériaux: Haute Température et Irradiation (CEMHT) CNRS, 3A rue de la Férollerie, 45071 Orléans (France); Materials Science and Informatics Laboratory, University of Djelfa, 17000 (Algeria); Ntsoenzok, E.; De Sousa-Meneses, D.; Hakim, B. [Conditions Extrêmes et Matériaux: Haute Température et Irradiation (CEMHT) CNRS, 3A rue de la Férollerie, 45071 Orléans (France); Beya-Wakata, A. [Département Physique, Université de Yaoundé 1 (Cameroon)

    2014-11-15

    Highlights: • We studied the distribution of implanted Xe in amorphous SiO{sub 2}. • Various energies and fluencies as well as thermal annealing were considered. • RBS and TEM characterizations were undertaken. • We demonstrated that Xe can be located at vacancy peak or at ion projected range. • When a dense layer of bubbles is formed, Xe is shifted to stable bubbles region. - Abstract: We studied the distribution of implanted Xe in amorphous SiO{sub 2}. Our results clearly showed that Xe profile is energy and fluence dependent. By varying ion energy from 50 to 300 keV, we found that its thermal out-diffusion is very conventional for the first two energies and unexpected for the highest energy. In that last case Xe main peak increases with thermal annealing. Instead of out-diffusing, Xe seems to be driven toward the main peak. The effect of ion fluence is similar to energy one with a conventional out-diffusion for lower fluences (5 × 10{sup 15} and 1 × 10{sup 16} cm{sup −2}) while higher fluences (3.5 × 10{sup 16} and 5 × 10{sup 16} cm{sup −2}) display an increase of the main peak with annealing. Such a behavior can be linked to the formation (or not) of a high density of stable bubbles.

  12. Ab initio potential energy surface and bound states for the Kr-OCS complex.

    Science.gov (United States)

    Feng, Eryin; Sun, Chunyan; Yu, Chunhua; Shao, Xi; Huang, Wuying

    2011-09-28

    The first ab initio potential energy surface of the Kr-OCS complex is developed using the coupled-cluster singles and doubles with noniterative inclusion of connected triples [CCSD(T)]. The mixed basis sets, aug-cc-pVTZ for the O, C, and S atom, and aug-cc-pVQZ-PP for the Kr atom, with an additional (3s3p2d1f) set of midbond functions are used. A potential model is represented by an analytical function whose parameters are fitted numerically to the single point energies computed at 228 configurations. The potential has a T-shaped global minimum and a local linear minimum. The global minimum occurs at R = 7.146 a(0), θ = 105.0° with energy of -270.73 cm(-1). Bound state energies up to J = 9 are calculated for three isotopomers (82)Kr-OCS, (84)Kr-OCS, and (86)Kr-OCS. Analysis of the vibrational wavefunctions and energies suggests the complex can exist in two isomeric forms: T-shaped and quasi-linear. The calculated transition frequencies and spectroscopic constants of the three isotopomers are in good agreement with the experimental values.

  13. Production of Hyperpolarized 129Xe Gas Without Nitrogen by Optical Pumping at 133Cs D2 line in Flow System

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xin; SUN Xian-Ping; LUO Jun; ZENG Xi-Zhi; LIU Mai-Li; ZHAN Ming-Sheng

    2004-01-01

    @@ We report production of hyperpolarized 129Xe gas via spin-exchange with optically pumped Cs atoms at the D2 line, achieved at low magnetic field in a flow system and in the absence of nitrogen gas. The nuclear spin polarization of hyperpolarized 129Xe gas is enhanced by a factor of 10000 compared to that without optical pumping under the same condition, which corresponds to polarization of about 2.66%. Due to the high spin polarization, the radiation damping of hyperpolarized 129Xe gas has also been observed in the flow system.

  14. Search for Majoron-emitting modes of double-beta decay of $^{136}$Xe with EXO-200

    CERN Document Server

    :,; Auty, D J; Barbeau, P S; Beauchamp, E; Beck, D; Belov, V; Benitez-Medina, C; Breidenbach, M; Brunner, T; Burenkov, A; Cao, G F; Chambers, C; Chaves, J; Cleveland, B; Coon, M; Craycraft, A; Daniels, T; Danilov, M; Daugherty, S J; Davis, C G; Davis, J; DeVoe, R; Delaquis, S; Didberidze, T; Dolgolenko, A; Dolinski, M J; Dunford, M; Fairbank, W; Farine, J; Feldmeier, W; Fierlinger, P; Fudenberg, D; Giroux, G; Gornea, R; Graham, K; Gratta, G; Hall, C; Herrin, S; Hughes, M; Jewell, M J; Jiang, X S; Johnson, A; Johnson, T N; Johnston, S; Karelin, A; Kaufman, L J; Killick, R; Koffas, T; Kravitz, S; Kuchenkov, A; Kumar, K S; Leonard, D S; Leonard, F; Licciardi, C; Lin, Y H; Ling, J; MacLellan, R; Marino, M G; Mong, B; Moore, D; Nelson, R; Odian, A; Ostrovskiy, I; Ouellet, C; Piepke, A; Pocar, A; Prescott, C Y; Rivas, A; Rowson, P C; Rozo, M P; Russell, J J; Schubert, A; Sinclair, D; Smith, E; Stekhanov, V; Tarka, M; Tolba, T; Tosi, D; Tsang, R; Twelker, K; Vogel, P; Vuilleumier, J -L; Waite, A; Walton, J; Walton, T; Weber, M; Wen, L J; Wichoski, U; Yang, L; Yen, Y -R; Zeldovich, O Ya

    2014-01-01

    EXO-200 is a single phase liquid xenon detector designed to search for neutrinoless double-beta decay of $^{136}$Xe. Here we report on a search for various Majoron-emitting modes based on 100 kg$\\cdot$yr exposure of $^{136}$Xe. A lower limit of $T^{^{136}Xe}_{1/2} >1.2...10^{24}$ yr at 90% C.L. on the half-life of the spectral index = 1 Majoron decay was obtained, corresponding to a constraint on the Majoron-neutrino coupling constant of $||<$ (0.8-1.7)...10$^{-5}$.

  15. Re-Evaluation of Ar-39 - Ar-40 Ages for Apollo Lunar Rocks 15415 and 60015

    Science.gov (United States)

    Park, J.; Nyquist, L. E.; Bogard, D. D.; Garrison, D. H.; Shih, C.-Y.

    2010-01-01

    We re-analyzed 39Ar-40Ar ages of Apollo lunar highland samples 15415 and 60015, two ferroan anorthosites analyzed previously in the 1970 s, with a more detailed approach and with revised decay constants. From these samples we carefully prepared 100-200 mesh mineral separates for analysis at the Noble Gas Laboratory at NASA-Johnson Space Center. The Ar-39-Ar-40 age spectra for 15415 yielded an age of 3851 +/- 38 Ma with 33-99% of Ar39 release, roughly in agreement with previously reported Ar-Ar ages. For 60015, we obtained an age of 3584 +/- 152 Ma in 23-98% of Ar39 release, also in agreement with previously reported Ar-Ar ages of approximately 3.5 Ga. Highland anorthosites like these are believed by many to be the original crust of the moon, formed by plagioclase floatation atop a magma ocean, however the Ar-Ar ages of 15415 and 60015 are considerably younger than lunar crust formation. By contrast, recently recovered lunar anorthosites such as Dhofar 489, Dhofar 908, and Yamato 86032 yield older Ar-Ar ages, up to 4.35 Ga, much closer to time of formation of the lunar crust. It follows that the Ar-Ar ages of the Apollo samples must have been reset by secondary heating, and that this heating affected highland anorthosites at both the Apollo 15 and Apollo 16 landing sites but did not affect lunar highland meteorites. One obvious consideration is that while the Apollo samples were collected from the near side of the moon, these lunar meteorites are thought to have originated from the lunar far side

  16. Photo-triggering and secondary electron produced ionization in electric discharge ArF* excimer lasers

    Science.gov (United States)

    Xiong, Zhongmin; Kushner, Mark J.

    2011-10-01

    Electric discharge excimer lasers are sustained in multi-atmosphere attaching gas mixtures that are typically preionized to enable a reproducible, uniform glow, which maximizes optical quality and gain. This preionization is often accomplished using UV light produced by a corona discharge within the plasma cavity. To quantify the relationship between corona discharge properties and those of the laser discharge, the triggering of electron avalanche by preionizing UV light in an electric discharge-pumped ArF* excimer laser was numerically investigated using a two-dimensional model. The preionizing UV fluxes were generated by a corona-bar discharge driven by the same voltage pulse as the main discharge sustained in a multi-atmospheric Ne/Ar/Xe/F2 gas mixture. The resulting peak photo-electron density in the inter-electrode spacing is around 108 cm-3, and its distribution is biased toward the UV source. The preionization density increases with increasing dielectric constant and capacitance of the corona bar. The symmetry and uniformity of the discharge are, however, improved significantly once the main avalanche develops. In addition to bulk electron impact ionization, the ionization generated by sheath accelerated secondary electrons was found to be important in sustaining the discharge current at experimentally observed values. At peak current, the magnitude of the ionization by sheath accelerated electrons is comparable to that from bulk electron impact in the vicinity of the cathode.

  17. Study of the symbiotic star AR Pavonis

    Directory of Open Access Journals (Sweden)

    C. Quiroga

    2001-01-01

    Full Text Available We present a study of the optical spectra and linear polarization of the eclipsing binary AR Pavonis. The optical spectra were obtained between 1990 and 1998, and polarimetric data between 1995 and 1998. From spectroscopic variations along the orbital motion we analized the nature of the system. Polarimetric studies indicate that AR Pav has intrinsic polarization.

  18. The Coronae of AR Lac

    CERN Document Server

    Huenemoerder, D P; Drake, J J; Sanz-Forcada, J; Canizares, Claude R.; Drake, Jeremy J.; Huenemoerder, David P.; Sanz-Forcada, Jorge

    2003-01-01

    We observed the coronally active eclipsing binary, AR Lac, with the High Energy Transmission Grating on Chandra for a total of 97 ks, spaced over five orbits, at quadratures and conjunctions. Contemporaneous and simultaneous EUV spectra and photometry were also obtained with the Extreme Ultraviolet Explorer. Significant variability in both X-ray and EUV fluxes were observed, dominated by at least one X-ray flare and one EUV flare. We saw no evidence of primary or secondary eclipses. X-ray flux modulation was largest at high temperature, indicative of flare heating of coronal plasma. Line widths interpreted in terms of Doppler broadening suggest that both binary stellar components are active. From line fluxes obtained from total integrated spectra, we have modeled the emission measure and abundance distributions. A strong maximum was found in the differential emission measure, characterized by peaks at log T = 6.9 and 7.4, together with a weak but significant cooler maximum near log T=6.2, and a moderately str...

  19. KR-31543 reduces the production of proinflammatory molecules in human endothelial cells and monocytes and attenuates atherosclerosis in mouse model.

    Science.gov (United States)

    Choi, Jae-Hoon; Yoo, Ji-Young; Kim, Sun-Ok; Yoo, Sung-Eun; Oh, Goo Taeg

    2012-12-31

    KR-31543, (2S, 3R, 4S)-6-amino-4-[N-(4-chlorophenyl)- N-(2-methyl-2H-tetrazol-5-ylmethyl) amino]-3,4-dihydro- 2-dimethyoxymethyl-3-hydroxy-2-methyl-2H-1-benz opyran is a new neuroprotective agent for ischemiareperfusion damage. It has also been reported that KR-31543 has protective effects on lipid peroxidation and H₂O₂-induced reactive oxygen species production. In this study, we investigated the anti-inflammatory and anti-atherogenic properties of KR-31543. We observed that KR-31543 treatment reduced the production of MCP-1, IL-8, and VCAM-1 in HUVECs, and of MCP-1 and IL-6 in THP-1 human monocytes. We also examined the effect of KR-31543 on monocytes migration in vitro. KR-31543 treatment effectively reduced the migration of THP-1 human monocytes to the HUVEC monolayer in a dose-dependent manner. We next examined the effects of this compound on atherogenesis in LDL receptor deficient (Ldlr ⁻/⁻) mice. After 10 weeks of western diet, the formation of atherosclerotic lesion in aorta was reduced in the KR-31543-treated group compared to the control group. The accumulation of macrophages in lesion was also reduced in KR-31543 treated group. However, the plasma levels of total cholesterol, HDL, LDL, and triglyceride were not affected by KR-31543 treatment. Taken together, these results show that KR-31543 has anti-inflammatory properties on human monocytes and endothelial cells, and inhibits fatty streak lesion formation in mouse model of atherosclerosis, suggesting the potential of KR-31543 for the treatment for atherosclerosis.

  20. Resonance-enhanced photon excitation spectroscopy of the even-parity autoionizing Rydberg states of Kr

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Kr atoms were produced in their metastable states 4p55s [3/2]2 and 4p55s’ [1/2]0 in a pulsed DC dis-charge in a beam,and subsequently excited to the even-parity autoionizing Rydberg states 4p5np’ [3/2]1,2,[1/2]1 and 4p5nf’ [5/2]3 using single photon excitation.The excitation spectra of the even-parity autoionizing resonance series from the metastable Kr were obtained by recording the autoionized Kr+ ions with time-of-flight ion detection in the photon energy range of 29000-40000 cm1.A wealth of autoionizing resonances were newly observed,from which more precise and more systematic spec-troscopic data of the level energy and quantum defects were derived.

  1. Resonance-enhanced photon excitation spectroscopy of the even-parity autoionizing Rydberg states of Kr

    Institute of Scientific and Technical Information of China (English)

    LI ChunYan; WANG TingTing; ZHEN JunFeng; ZHANG Qun; CHEN Yang

    2009-01-01

    Kr atoms were produced in their metastable states 4p55s [3/2]2 and 4p55s' [1/2]0 in a pulsed DC discharge in a beam, and subsequently excited to the even-parity autoionizing Rydberg states 4p5np' [3/2]1,2, [1/2]1 and 4p5nf' [5/2]3 using single photon excitation. The excitation spectra of the even-parity autoionizing resonance series from the metastable Kr were obtained by recording the autoionized Kr+ ions with time-of-flight ion detection in the photon energy range of 29000-40000 cm-1. A wealth of autoionizing resonances were newly observed, from which more precise and more systematic spec-troscopic data of the level energy and quantum defects were derived.

  2. New stage of search for 2K(2ν) capture of 78Kr

    Science.gov (United States)

    Gavriljuk, Ju. M.; Gangapshev, A. M.; Gavrin, V. N.; Kazalov, V. V.; Kuzminov, V. V.; Osetrova, N. Ya.; Panasenko, S. I.; Pul'Nikov, I. I.; Ratkevich, S. S.; Ryabukhin, A. V.; Shubin, A. N.; Skorynin, G. V.

    2006-12-01

    A technique to search for 2K capture of 78Kr with a large low-background proportional counter filled with a sample of krypton enriched in 78Kr up to 99.8% at a pressure of 4.51 atm is described in this paper. The results of first measurements are presented. An analysis of data collected for 159 h yielded a new limit to the half-life of 78Kr with regard to 2K capture (T 1/2 ≥ 1.5 × 1021 yr (90% C.L.)). The sensitivity of the facility to the process for one year of measurement was evaluated to be S = 1.0 × 1022 yr (90% C.L.).

  3. Revised error propagation of 40Ar/39Ar data, including covariances

    Science.gov (United States)

    Vermeesch, Pieter

    2015-12-01

    The main advantage of the 40Ar/39Ar method over conventional K-Ar dating is that it does not depend on any absolute abundance or concentration measurements, but only uses the relative ratios between five isotopes of the same element -argon- which can be measured with great precision on a noble gas mass spectrometer. The relative abundances of the argon isotopes are subject to a constant sum constraint, which imposes a covariant structure on the data: the relative amount of any of the five isotopes can always be obtained from that of the other four. Thus, the 40Ar/39Ar method is a classic example of a 'compositional data problem'. In addition to the constant sum constraint, covariances are introduced by a host of other processes, including data acquisition, blank correction, detector calibration, mass fractionation, decay correction, interference correction, atmospheric argon correction, interpolation of the irradiation parameter, and age calculation. The myriad of correlated errors arising during the data reduction are best handled by casting the 40Ar/39Ar data reduction protocol in a matrix form. The completely revised workflow presented in this paper is implemented in a new software platform, Ar-Ar_Redux, which takes raw mass spectrometer data as input and generates accurate 40Ar/39Ar ages and their (co-)variances as output. Ar-Ar_Redux accounts for all sources of analytical uncertainty, including those associated with decay constants and the air ratio. Knowing the covariance matrix of the ages removes the need to consider 'internal' and 'external' uncertainties separately when calculating (weighted) mean ages. Ar-Ar_Redux is built on the same principles as its sibling program in the U-Pb community (U-Pb_Redux), thus improving the intercomparability of the two methods with tangible benefits to the accuracy of the geologic time scale. The program can be downloaded free of charge from

  4. 40Ar/39Ar ages of lunar impact glasses: Relationships among Ar diffusivity, chemical composition, shape, and size

    CERN Document Server

    Zellner, N E B

    2015-01-01

    Lunar impact glasses, quenched melts produced during cratering events on the Moon, have the potential to provide not only compositional information about both the local and regional geology of the Moon but also information about the impact flux over time. We present in this paper the results of 73 new 40Ar/39Ar analyses of well-characterized, inclusion-free lunar impact glasses and demonstrate that size, shape, chemical composition, fraction of radiogenic 40Ar retained, and cosmic ray exposure (CRE) ages are important for 40Ar/39Ar investigations of these samples. Specifically, analyses of lunar impact glasses from the Apollo 14, 16, and 17 landing sites indicate that retention of radiogenic 40Ar is a strong function of post-formation thermal history in the lunar regolith, size, and chemical composition. Based on the relationships presented in this paper, lunar impact glasses with compositions and sizes sufficient to have retained 90% of their radiogenic Ar during 750 Ma of cosmic ray exposure at time-integra...

  5. Influence of noble gas ion polishing species on extreme ultraviolet mirrors

    NARCIS (Netherlands)

    Boogaard, van den A.J.R.; Zoethout, E.; Makhotkin, I.A.; Louis, E.; Bijkerk, F.

    2012-01-01

    Low energy ion polishing is attractive in thin films because of the small interaction zone with the treated material. In this context, various noble gases (Ne, Ar, Kr, and Xe) have been applied for low energy ion polishing of interfaces in nanoscale optical Mo/Si multilayers in order to mitigate the

  6. Relativistic calculations of angle-dependent photoemission time delay

    Science.gov (United States)

    Kheifets, Anatoli; Mandal, Ankur; Deshmukh, Pranawa C.; Dolmatov, Valeriy K.; Keating, David A.; Manson, Steven T.

    2016-07-01

    Angular dependence of photoemission time delay for the valence n p3 /2 and n p1 /2 subshells of Ar, Kr, and Xe is studied in the dipole relativistic random phase approximation. Strong angular anisotropy of the time delay is reproduced near respective Cooper minima while the spin-orbit splitting affects the time delay near threshold.

  7. Effect of sputter gas on the physical and magnetic microstructure of Co/Cu multilayers

    NARCIS (Netherlands)

    Donnet, D.M.; Tsutsumi, K.; Haan, de P.; Lodder, J.C.

    1996-01-01

    The physical structure of Co/Cu multilayers, sputtered in different gases (Ar, Kr, and Xe) together with the domain structures that these films support have been investigated using electron microscopy in an attempt to explain the differences in their measured magnetoresistance (MR). Both planar and

  8. Relativistic calculations of angular dependent photoemission time delay

    CERN Document Server

    Kheifets, A S; Deshmukh, P C; Dolmatov, V K; Manson, S T

    2016-01-01

    Angular dependence of photoemission time delay for the valence $np_{3/2}$ and $np_{1/2}$ subshells of Ar, Kr and Xe is studied in the dipole relativistic random phase approximation. Strong angular anisotropy of the time delay is reproduced near respective Cooper minima while the spin-orbit splitting affects the time delay near threshold.

  9. Spatial evaluation of Ar-systematics in rocks from the British Channel Islands: a UV laserprobe Ar/Ar study of excess 40Ar

    Science.gov (United States)

    Schwenzer, S. P.; Sherlock, S.; Kelley, S. P.

    2010-12-01

    The Ar-Ar method is a powerful tool for constraining thermal histories of metamorphic and plutonic rocks, most commonly undertaken on potassium rich mineral separates rather than whole rocks. While this approach usually yields reasonable thermal histories, it is rarely as precise as dating volcanics, and such rocks are also frequently contaminated by excess argon, artificially elevating the Ar-Ar ages. Understanding the evolution of excess argon represents a challenge; whilst it is possible to discern the ‘sink’ as the host mineral now contaminated by excess argon, examining the ‘source’ and ‘transport’ mechanism is more challenging. The approach we have taken here is to combine measurements of potassium rich and potassium poor minerals to understand the argon reservoirs and argon transfer between minerals, grain boundaries and fluids. Considering the system as a whole provides a method for understanding the complete history of the rock and thus assessing any interactions which may impact on the interpretation of ages and thermal history [Kelley, 2002, Chem. Geol. 188]. Here we have studied a series of plutonic and metamorphic basement samples from the British Channel Islands with different ages and post-emplacement histories, namely Icart Gneiss, Perelle Quartz Diorite, L’Ancresse Granodiorite, and Bordeaux Diorite. The formation age of Icart Gneiss is ~2000 Ma [D’Lemos et al., 1990, Geol. Soc. Spec. Pub. 51]. Ar-Ar ages of hornblendes and biotites from quartz diorites on Guernsey and Sark range between 606 and 596 Ma [Dallmeyer et al. 1991, J. Geol. Soc. London 148], whilst U-Pb zircon ages are in the range 710 to 613 Ma [Dallmeyer et al. 1991; Samson & D’Lemos 1998, J. Geol. Soc. London 155; Miller et al. 1999, Tectonophysics 132]. Detailed petrograpic (microscope, electron microprobe) investigations established the crystallization and deformation history of the samples, and revealed that post-magmatic alteration is unevenly distributed. This

  10. Charge distribution of Kr ions produced upon photoionization around the 2s edge

    Energy Technology Data Exchange (ETDEWEB)

    Santos, A.C.F., E-mail: toni@if.ufrj.br [Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21991-972 (Brazil); Pilling, S. [Laboratório Nacional de Luz Síncroton, Campinas 13084-971 (Brazil); Almeida, D.P. [Departamento de Física, Universidade Federal de Santa Catarina, Florianópolis 88040-979 (Brazil)

    2015-08-15

    Highlights: • Charge spectra of Kr after photoionization of the L shell have been measured. • Multiple photoionization of krypton around the 2s edge is a collective process. • Electron correlation plays an important role in multiple ionization of heavy atoms. - Abstract: Charge state spectra of krypton ions generated after ionization (by a single photon) of the L shell have been measured by using the PEPICO technique. Relative abundances of Kr{sup q+} ions in charge state up to 8+ were obtained using monochromatized synchrotron radiation. A comparison with other experimental and theoretical data is presented.

  11. β Decay in the Region of Neutron-deficient {sup 69,70,71}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, A.M., E-mail: ARogers@lbl.gov [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA, 94720 (United States); Giovinazzo, J. [Centre d' Etudes Nucléaires de Bordeaux-Gradignan, Université Bordeaux 1, UMR 5797 CNRS/IN2P3, Chemin du Solarium, BP 120, F-33175, Gardignan Cedex (France); Lister, C.J. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Blank, B.; Canchel, G. [Centre d' Etudes Nucléaires de Bordeaux-Gradignan, Université Bordeaux 1, UMR 5797 CNRS/IN2P3, Chemin du Solarium, BP 120, F-33175, Gardignan Cedex (France); Clark, J.A. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); France, G. de; Grévy, S. [GANIL CEA/DSM-CNRS/IN2P3, Boulevard Henri Becquerel, BP55027, 14076 CEAN Cedex 5 (France); Gros, S.; McCutchan, E.A. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Oliveira Santos, F. de [GANIL CEA/DSM-CNRS/IN2P3, Boulevard Henri Becquerel, BP55027, 14076 CEAN Cedex 5 (France); Savard, G.; Seweryniak, D. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Stefan, I.; Thomas, J.-C. [GANIL CEA/DSM-CNRS/IN2P3, Boulevard Henri Becquerel, BP55027, 14076 CEAN Cedex 5 (France)

    2014-06-15

    Decay spectroscopy was performed for neutron-deficient nuclei ranging from zinc to krypton with isospin −3/2 ≤T{sub z}≤0. Measurements of correlated β-delayed protons allowed us to determine the isobaric analog states fed from the decay of {sup 65}Se and {sup 69}Kr, constraining the spin of the {sup 69}Kr ground state. Preliminary results regarding the half lives for the T{sub z}=−1 systems, relevant to the rapid proton capture (rp) process, are discussed.

  12. FY-12 INL KR CAPTURE ACTIVITIES SUPPORTING THE OFF-GAS SIGMA TEAM

    Energy Technology Data Exchange (ETDEWEB)

    Troy G. Garn; Mitchell R. Greenhalgh; Jack D Law

    2012-08-01

    Tasks performed this year by INL Kr capture off-gas team members can be segregated into three separate task sub-sections which include: 1) The development and testing of a new engineered form sorbent, 2) An initial NDA gamma scan effort performed on the drum containing the Legacy Kr-85 sample materials, and 3) Collaborative research efforts with PNNL involving the testing of the Ni-DOBDC MOF and an initial attempt to make powdered chalcogel material into an engineered form using our binding process. This document describes the routes to success for the three task sub-sections.

  13. Core drilling of deep drillhole OL-KR57 at Olkiluoto in Eurajoki 2011-2012

    Energy Technology Data Exchange (ETDEWEB)

    Toropainen, V. [Suomen Malmi Oy, Espoo (Finland)

    2012-07-15

    As a part of the confirming site investigations at Olkiluoto, Suomen Malmi Oy (Smoy) core drilled 401.71 m and 45.01 m deep drillholes, OL-KR57 and OL-KR57B, at Olkiluoto in September 2011 - January 2012. The diameter of the drillholes is 75.7 mm. A set of monitoring measurements and samplings from the drilling and returning water was carried out during the drilling. Both the volume and the electric conductivity of the returning and drilling water were recorded. The drill rig was computer controlled and the computer recorded drilling parameters during drilling. The objective of the measurements was to obtain more information about bedrock and groundwater properties. Sodium fluorescein was used as a label agent in the drilling water. The total volumes of the used drilling, flushing and washing water were 350 m3 and 30 m3 in the drillholes OL-KR57 and OL-KR57B, respectively. The measured volumes of the returning water in the drillholes were 328 m{sup 3} and 16.8 m{sup 3}, respectively. The deviations of the drillholes were measured with the deviation measuring instruments EMS and Gyro. Uniaxial compressive strength, Young's Modulus and Poisson's ratio were measured from the core samples. The average uniaxial compressive strength was 123.9 MPa, the average Young's Modulus was 42.6 GPa and the average Poisson's ratio was 0.23. The main rock types are veined and diatexitic gneisses, mica gneiss and tonaliticgranodioritic- granitic gneiss. The average fracture frequency is 2.5 pcs/m in drillhole OL-KR57 and 3.3 pcs/m in the drillhole OL-KR57B. The average RQD values are 95.0 % and 93.0 %. Seven separate fractured zones were interpreted from OL-KR57 and three fractured zones from OL-KR57B. (orig.)

  14. Qualitative risk assessment for the 100-KR-4 groundwater operable unit

    Energy Technology Data Exchange (ETDEWEB)

    Biggerstaff, R.L.

    1994-06-30

    This report provides the qualitative risk assessment (QRA) for the 100-KR-4 groundwater operable unit at the US Department of Energy`s (DOE) Hanford Site in southeastern Washington State. The extent of the groundwater beneath the 100 K Area is defined in the Remedial Investigation/Feasibility Study Work Plan for the 100-KR-4 Operable Unit (DOE-RL 1992a). The QRA is an evaluation or risk using a limited amount of data and a predefined set of human and environmental exposure scenarios and is not intended to replace or be a substitute for a baseline risk assessment.

  15. 40Ar/39Ar Ages of Carbonaceous Xenoliths in 2 HED Meteorites

    Science.gov (United States)

    Turrin, B.; Lindsay, F. N.; Park, J.; Herzog, G. F.; Delaney, J. S.; Swisher, C. C., III; Johnson, J.; Zolensky, M.

    2016-01-01

    The generally young K/Ar and 40Ar/39Ar ages of CM chondrites made us wonder whether carbonaceous xenoliths (CMX) entombed in Howardite–Eucrite–Diogenite (HED) meteorites might retain more radiogenic 40Ar than do ‘free-range’ CM-chondrites. To find out, we selected two HED breccias with carbonaceous inclusions in order to compare the 40Ar/39Ar release patterns and ages of the inclusions with those of nearby HED material. Carbonaceous inclusions (CMXs) in two HED meteorites lost a greater fraction of radiogenic 40Ar than did surrounding host material, but a smaller fraction of it than did free-range CM-chondrites such as Murchison or more heavily altered ones. Importantly, however, the siting of the CMXs in HED matrix did not prevent the 40Ar loss of about 40 percent of the radiogenic 40Ar, even from phases that degas at high laboratory temperatures. We infer that carbonaceous asteroids with perihelia of 1 astronomical unit probably experience losses of at least this size. The usefulness of 40Ar/39Ar dating for samples returned from C-type asteroids may hinge, therefore, on identifying and analyzing separately small quantities of the most retentive phases of carbonaceous chondrites.

  16. Molecular dynamics study on low-energy sputtering of carbon material by Xe ion bombardment

    Science.gov (United States)

    Muramoto, T.; Hyakutake, T.

    2013-05-01

    The low-energy sputtering of carbon material under Xe ion bombardment is studied through the molecular dynamics (MD) simulation. For the normal incidence of Xe, the MD result of sputtering yield almost agrees with the experimental result by Williams et al. (AIAA-2004-3788). However, the experimental result shows a less incident angle dependence than the MD result because the experiment performed on a rough surface. It is found that the sputtered particles have memory of the projectile because the sputtered particles by the low-energy projectile undergo only a few collisions before the ejection. Low density of an amorphous carbon surface brings the decrease of the sputtering yield and the increase of high-energy sputtered atoms.

  17. Experimental studies of self-suppression of vacuum ultraviolet generation in Xe

    Energy Technology Data Exchange (ETDEWEB)

    Judish, J.P.; Allman, S.L.; Garrett, W.R.; Payne, M.G.

    1988-11-01

    Vacuum ultraviolet light in the range 116 nm to 117 nm was produced by using a two-photon resonant four-wave mixing scheme in Xe. The buildup of coherent cancellation of the two-photon resonant transition employed in the generation of the vacuum ultraviolet, with resulting limitations imposed on the achievable vacuum ultraviolet intensity was investigated. Under certain predicted conditions, increases in the intensity of one of the pumping beams, approx.1500 nm infrared, or tuning this beam towards resonance with the 5p/sup 5/7s(3/2)/sub 1/ level of Xe led, not to increases, but decreases in the vacuum ultraviolet generated. 3 refs., 3 figs.

  18. REVISED AND EXTENDED ANALYSIS OF FIVE TIMES IONIZED XENON, Xe VI

    Energy Technology Data Exchange (ETDEWEB)

    Gallardo, M.; Raineri, M.; Reyna Almandos, J. [Centro de Investigaciones Opticas (CIOp), CC 3, 1897, Gonnet, La Plata (Argentina); Pagan, C. J. B.; Abrahão, R. A., E-mail: monicar@ciop.unlp.edu.ar, E-mail: cesarpagan@fee.unicamp.br [School of Electrical and Computer Engineering, University of Campinas (UNICAMP), 13083-852, Campinas, SP (Brazil)

    2015-01-01

    A capillary discharge tube was used to record the Xe spectrum in the 400-5500 Å  region. A set of 243 lines of the Xe VI spectrum was observed, and 146 of them were classified for the first time. For all known lines, we calculated the weighted oscillator strengths (gf) and weighted transition probabilities (gA) using the configuration interaction in a relativistic Hartree-Fock approach. The energy matrix was calculated using energy parameters adjusted to fit the experimental energy levels. Core polarization effects were taken into account in our calculations. Experimental energy values and calculated lifetimes are also presented for a set of 88 levels. From these levels, 32 were classified for the first time and 33 had their values revised. Our analysis of the 5s5p5d and 5s5p6s configurations was extended in order to clarify discrepancies among previous works.

  19. Search for Two-Neutrino Double Electron Capture of $^{124}$Xe with XENON100

    CERN Document Server

    Aprile, E; Agostini, F; Alfonsi, M; Amaro, F D; Anthony, M; Arneodo, F; Barrow, P; Baudis, L; Bauermeister, B; Benabderrahmane, M L; Berger, T; Breur, P A; Brown, A; Brown, E; Bruenner, S; Bruno, G; Budnik, R; Bütikofer, L; Calvén, J; Cardoso, J M R; Cervantes, M; Cichon, D; Coderre, D; Colijn, A P; Conrad, J; Cussonneau, J P; Decowski, M P; de Perio, P; Di Gangi, P; Di Giovanni, A; Diglio, S; Duchovni, E; Fei, J; Ferella, A D; Fieguth, A; Franco, D; Fulgione, W; Rosso, A Gallo; Galloway, M; Gao, F; Garbini, M; Geis, C; Goetzke, L W; Greene, Z; Grignon, C; Hasterok, C; Hogenbirk, E; Itay, R; Kaminsky, B; Kessler, G; Kish, A; Landsman, H; Lang, R F; Lellouch, D; Levinson, L; Calloch, M Le; Levy, C; Lin, Q; Lindemann, S; Lindner, M; Lopes, J A M; Manfredini, A; Undagoitia, T Marrodán; Masbou, J; Massoli, F V; Masson, D; Mayani, D; Meng, Y; Messina, M; Micheneau, K; Miguez, B; Molinario, A; Murra, M; Naganoma, J; Ni, K; Oberlack, U; Orrigo, S E A; Pakarha, P; Pelssers, B; Persiani, R; Piastra, F; Pienaar, J; Piro, M -C; Plante, G; Priel, N; Rauch, L; Reichard, S; Reuter, C; Rizzo, A; Rosendahl, S; Rupp, N; Santos, J M F dos; Sartorelli, G; Scheibelhut, M; Schindler, S; Schreiner, J; Schumann, M; Lavina, L Scotto; Selvi, M; Shagin, P; Silva, M; Simgen, H; Sivers, M v; Stein, A; Thers, D; Tiseni, A; Trinchero, G; Tunnell, C D; Wall, R; Wang, H; Weber, M; Wei, Y; Weinheimer, C; Wulf, J; Zhang, Y

    2016-01-01

    Two-neutrino double electron capture is a rare nuclear decay where two electrons are simultaneously captured from the atomic shell. For $^{124}$Xe this process has not yet been observed and its detection would provide a new reference for nuclear matrix element calculations. We have conducted a search for two-neutrino double electron capture from the K-shell of $^{124}$Xe using 7636 kg$\\cdot$d of data from the XENON100 dark matter detector. Using a Bayesian analysis we observed no significant excess above background, leading to a lower 90 % credibility limit on the half-life $T_{1/2}>6.5\\times10^{20}$ yr. We also evaluated the sensitivity of the XENON1T experiment, which is currently being commissioned, and find a sensitivity of $T_{1/2}>6.1\\times10^{22}$ yr after an exposure of 2 t$\\cdot$yr.

  20. Plunger lifetime measurements in {sup 128}Xe using Coulomb excitation in inverse kinematics

    Energy Technology Data Exchange (ETDEWEB)

    Rother, Wolfram; Dewald, Alfred; Ilie, Gabriela; Pissulla, Thomas; Melon, Barbara; Jolie, Jan; Pascovici, Gheorghe; Zell, Karl-Oskar [IKP, Universitaet zu Koeln, Koeln (Germany); Julin, Rauno; Jones, Peter; Greenless, Paul; Rahkila, Panu; Scholey, Cath [JYFL, University of Jyvaeskylae, Jyvaeskylae (Finland); Harissopulos, Sotirios; Lagoyannis, Anastasios; Konstantinopoulos, T. [INP, N.C.S.R. ' ' Demokritos' ' , Athens (Greece); Grahn, Tuomas [JYFL, University of Jyvaeskylae, Jyvaeskylae (Finland)]|[Oliver Lodge Lab., University of Liverpool, Liverpool (United Kingdom); Balabanski, Dimiter [INRNE, Sofia (Bulgaria)

    2008-07-01

    We report on an experiment using Coulomb excitation in inverse kinematics in combination with the plunger technique for measuring lifetimes of excited states of the projectile. Aside from the investigation of E(2) features in {sup 128}Xe, the aim was to explore the special features of such experiments which are also suited to be used with radioactive beams. The measurement was performed at the JYFL with the Koeln coincidence plunger device and the JuroGam spectrometer using a {sup 128}Xe beam impinging on a {sup nat}Fe target at a beam energy of 525 MeV. Recoils were detected by means of 32 solar cells placed at extrem forward angles. Recoil-gated {gamma}-singles and {gamma}{gamma}-coincidences were measured at different target-degrader distances. Details of the experiment and first results are presented.

  1. Clathrate Structure Determination by Combining Crystal Structure Prediction with Computational and Experimental (129) Xe NMR Spectroscopy.

    Science.gov (United States)

    Selent, Marcin; Nyman, Jonas; Roukala, Juho; Ilczyszyn, Marek; Oilunkaniemi, Raija; Bygrave, Peter J; Laitinen, Risto; Jokisaari, Jukka; Day, Graeme M; Lantto, Perttu

    2017-01-23

    An approach is presented for the structure determination of clathrates using NMR spectroscopy of enclathrated xenon to select from a set of predicted crystal structures. Crystal structure prediction methods have been used to generate an ensemble of putative structures of o- and m-fluorophenol, whose previously unknown clathrate structures have been studied by (129) Xe NMR spectroscopy. The high sensitivity of the (129) Xe chemical shift tensor to the chemical environment and shape of the crystalline cavity makes it ideal as a probe for porous materials. The experimental powder NMR spectra can be used to directly confirm or reject hypothetical crystal structures generated by computational prediction, whose chemical shift tensors have been simulated using density functional theory. For each fluorophenol isomer one predicted crystal structure was found, whose measured and computed chemical shift tensors agree within experimental and computational error margins and these are thus proposed as the true fluorophenol xenon clathrate structures.

  2. Prototype of a high-power, high-energy industrial XeCl laser

    Science.gov (United States)

    Borisov, V. M.; Demin, A. I.; Khristoforov, O. B.

    2015-03-01

    We discuss the results of fabrication and experimental study of a high-power excimer XeCl laser for industrial applications. Compactness of the laser is achieved by the employment of a laser chamber based on a ceramic tube made of Al2O3. High laser output energy (1.5 - 2.5 J pulse-1) is obtained using a wide-aperture (up to 55 × 30 mm) volume discharge with pre-ionisation by a creeping discharge. The pre-ionisation is realised through a semitransparent electrode by the UV radiation of a creeping discharge in the form of uniform plasma sheet on a surface of a plane sapphire plate. The operating lifetime of the gas mixture amounts to ~57 × 106 pulses at a stabilised average laser power of 450 W. The results obtained demonstrate real prospects for developing a new class of excimer XeCl lasers with an average power of ~1 kW.

  3. Nuclear matrix element for two neutrino double beta decay from 136Xe

    CERN Document Server

    Ejiri, Hiroyasu

    2012-01-01

    The nuclear matrix element for the two neutrino double beta decay (DBD) of 136Xe was evaluated by FSQP (Fermi Surface Quasi Particle model), where experimental GT strengths measured by the charge exchange reaction and those by the beta decay rates were used. The 2 neutrino DBD matrix element is given by the sum of products of the single beta matrix elements via low-lying (Fermi Surface) quasi-particle states in the intermediate nucleus. 136Xe is the semi-magic nucleus with the closed neutron-shell, and the beta + transitions are almost blocked. Thus the 2 neutrino DBD is much suppressed. The evaluated 2 neutrino DBD matrix element is consistent with the observed value.

  4. Study of gas-fluidization dynamics with laser-polarized 129Xe.

    Science.gov (United States)

    Wang, Ruopeng; Rosen, Matthew Scott; Candela, Donald; Mair, Ross William; Walsworth, Ronald Lee

    2005-02-01

    We report initial NMR studies of gas dynamics in a particle bed fluidized by laser-polarized xenon (129Xe) gas. We have made preliminary measurements of two important characteristics: gas exchange between the bubble and emulsion phases and the gas velocity distribution in the bed. We used T2* contrast to differentiate the bubble and emulsion phases by choosing solid particles with large magnetic susceptibility. Experimental tests demonstrated that this method was successful in eliminating 129Xe magnetization in the emulsion phase, which enabled us to observe the time dependence of the bubble magnetization. By employing the pulsed field gradient method, we also measured the gas velocity distribution within the bed. These results clearly show the onset of bubbling and can be used to deduce information about gas and particle motion in the fluidized bed.

  5. Resonance-Enhanced Photon Excitation Spectroscopy of the Even-Parity Autoionizing Rydberg States of Xe

    Institute of Scientific and Technical Information of China (English)

    Chun-yan Li; Ting-ting Wang; Jun-feng Zhen; Qun Zhang; Yang Chen

    2008-01-01

    Xenon atoms were produced in their metastable states 5p56s[3/2]2 and 5p56s'[1/2]0 in a pulsed DC discharge in a beam, and subsequently excited to the even-parity autoionizing Rydberg states 5p5np' [3/2] 1 ,[1/2]1, t, and 5p5 nf'[5/2]3 using single photon excitation. The excitation spectra of the even-parity autoionizing resonance series from the metastable 129Xe were obtained by recording the autoionized Xe+ with time-of-flight ion detection in the photon energy range of 28000-42000 cm-1. A wealth of autoionizing resonances were newly observed, from which more precise and systematic spectroscopic data of the level energies and quantum defects were derived.

  6. Shell Model description of the {beta}{beta} decay of {sup 136}Xe

    Energy Technology Data Exchange (ETDEWEB)

    Caurier, E.; Nowacki, F. [IPHC, IN2P3-CNRS/Universite Louis Pasteur BP 28, F-67037 Strasbourg Cedex 2 (France); Poves, A., E-mail: alfredo.poves@uam.es [Departamento de Fisica Teorica, Universidad Autonoma de Madrid and Instituto de Fisica Teorica, UAM/CSIC, E-28049, Madrid (Spain)

    2012-05-01

    We study in this Letter the double beta decay of {sup 136}Xe with emission of two neutrinos which has been recently measured by the EXO-200 Collaboration. We use the same shell model framework, valence space, and effective interaction that we have already employed in our calculation of the nuclear matrix element (NME) of its neutrinoless double beta decay. Using the quenching factor of the Gamow-Teller operator which is needed to reproduce the very recent high resolution {sup 136}Xe ({sup 3}He, t) {sup 136}Cs data, we obtain a nuclear matrix element M{sup 2{nu}}=0.025 MeV{sup -1} compared with the experimental value M{sup 2{nu}}=0.019(2) MeV{sup -1}.

  7. Using the DFT-D method to describe dispersion interactions in systems of weakly-bonded Xe-aromatic molecules

    Science.gov (United States)

    Andriichenko, N. N.; Ermilov, A. Yu.

    2013-08-01

    The optimum version of the DFT-D class of methods (BHHLYP-D2, 6-31G*) is chosen to describe binding in a Xe-phenol system with the aim of subsequent KM/MM calculations for complex Xe-containing protein systems. It is shown that the stability of the Xe-phenol system is due to weak dispersion interactions not described in conventional approaches using the density functional. The MP2 approach using the (aug)-cc-pVTZ basis and Stuttgart pseudopotential, which yield the best reproduction of the characteristics of a Xe2 xenon dimer, is chosen as the reference standard. It is noted that the 2010 DFT-D3 methods underestimate the binding energy by a factor of nearly three, while DFT methods without dispersion corrections do not reproduce the stability of Xe2 and Xe-phenol systems. It is found that in the best version of calculations, BHHLYP-D2, the binding energy in Xe-phenol complex is estimated to be 2.7 kcal/mol versus the 3.1 kcal/mol found using the comparative approach. It is concluded that BHHLYP-D2 adequately reproduces the difference between the two conformers of the Xe-phenol complex and trend toward an increase in binding energy in the series of aromatic amino acids (phenylalanine, tyrosine, and tryptophan). DFT-D can also indicate the existence of excess conformers that are missing in systems according to more precise descriptions (MP2/(aug)-cc-pVTZ).

  8. SMALL VOLUME LONG PULSE X RAY PREIONISED XeCl LASER WITH DOUBLE DISCHARGE AND FAST FERRITE MAGNETIC SWITCH

    OpenAIRE

    J. Hueber; Kobhio, M.; Fontaine, B.; Delaporte, Ph.; Sentis, M.; Forestier, B.

    1991-01-01

    Experimental results obtained with a high efficiency small volume long pulse X-Ray preionised XeCl laser with double discharge and very fast ferrite magnetic switch are presented and compared with the results given by a new XeCl laser numerical self consistant model. The model takes into account most recent kinetic data and time variation of discharge impedence and switch inductance. There is a good agreement between experiment and model on electrical and laser parameters for typical conditions.

  9. 78 FR 76405 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel SALISH SEA-KR; Invitation for...

    Science.gov (United States)

    2013-12-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Maritime Administration Requested Administrative Waiver of the Coastwise Trade Laws: Vessel SALISH SEA-KR... of the vessel SALISH SEA-KR is: Intended Commercial Use Of Vessel: ``Passenger Vessel,...

  10. The Effectiveness of Local Culture-Based Mathematical Heuristic-KR Learning towards Enhancing Student's Creative Thinking Skill

    Science.gov (United States)

    Tandiseru, Selvi Rajuaty

    2015-01-01

    The problem in this research is the lack of creative thinking skills of students. One of the learning models that is expected to enhance student's creative thinking skill is the local culture-based mathematical heuristic-KR learning model (LC-BMHLM). Heuristic-KR is a learning model which was introduced by Krulik and Rudnick (1995) that is the…

  11. Activation of BmGSTd1 promoter and regulation by transcription factor Krüppel (Kr) in silkworm, Bombyx mori.

    Science.gov (United States)

    Zhao, Guodong; Wang, Binbin; Liu, Yunlei; Du, Jie; Li, Bing; Chen, Yuhua; Xu, Yaxiang; Shen, Weide; Xia, Qingyou; Wei, Zhengguo

    2014-11-10

    The Glutathione S-transferases (GSTs) are a large family of multifunctional enzymes, many of which play an important role in the detoxification of endogenous and exogenous toxic substances. In this research, firstly, we measured the rutin-induced transcriptional level of BmGSTd1 gene by using real-time quantitative RT-PCR method and dual spike-in strategy. The activities of the BmGSTd1 promoter in various tissues of silkworm were measured by firefly luciferase activity and normalized by the Renilla luciferase activity. Results showed that the activity of the BmGSTd1 promoter were highest in Malpighian tubule, followed by fat body, silk gland, hemocyte, epidermis, and midgut. The essential region for basal and rutin-induced transcriptional activity was -1573 to -931bp in Malpighian tubule and fat body of silkworm. Promoter truncation analysis using a dual-luciferase reporter assay in BmN cells showed that the region -1288 to -1202bp for BmGSTd1 gene was essential for basal and rutin-induced transcriptional activity. Sequence analysis of this region revealed several potential transcriptional regulatory elements such as Bcd and Kr. The mutation of core base of Kr site demonstrated that Kr functioned positively in rutin-mediated BmGSTd1 transcription.

  12. The Effect of Xe Underlayers on the Surface Enhanced Raman Scattering of Pyridine on Cold Silver.

    Science.gov (United States)

    1984-11-01

    enhancement effect on deposited pyridine can be dramatically reduced. ~Present address: INIFTA, Division Fisicoquimica de Superficies, CC 16, * Suc...is increased beyond 70K we see dramatic increases in peaks for all four - quadrant. See Figure 3. Certain structural changes begin to take place at...this stage. One such changes is the beginning of appreciable sublimation of the physisorbed Xe, even out of the pores. 18 Another change might involve

  13. Experimental evidence of Xe incorporation in Schottky defects in UO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Bès, René, E-mail: rene.bes@cea.fr [CEA, DEN, DEC, F-13108 Saint Paul Lez Durance Cedex (France); Synchrotron SOLEIL, Ligne de Lumière MARS, L' Ormes des Merisiers, Saint Aubin, BP48, F-91192 Gif-sur-Yvette Cedex (France); Martin, Philippe, E-mail: philippe-m.martin@cea.fr; Vathonne, Emerson; Delorme, Rémy; Sabathier, Catherine; Freyss, Michel; Bertolus, Marjorie [CEA, DEN, DEC, F-13108 Saint Paul Lez Durance Cedex (France); Glatzel, Pieter [European Synchrotron Radiation Facility (ESRF), 6 Rue Jules Horowitz, BP 220, 38043 Grenoble Cedex 9 (France)

    2015-03-16

    We report here the direct experimental observation of the preferential xenon incorporation site in uranium dioxide and analyse how its incorporation evolves with the annealing temperature. We show that High Energy Resolution Fluorescence Detection X-ray Absorption Near Edge Structure in combination with first-principles calculations enable a precise determination of the Xe incorporation site. Our finding provides important insight for the understanding and modeling of noble gases behavior in nuclear oxide fuel.

  14. Effective dynamic moment of inertia of /sup 118/Xe and /sup 130/Ba

    Energy Technology Data Exchange (ETDEWEB)

    El-Samman, H.; Barci, V.; Gizon, A.; Gizon, J.; Kossakowski, R.; Lindblad, T.; Bengtsson, T.

    1985-09-05

    The effective moment of inertia Jsub(eff)sup((2)) of /sup 118/Xe and /sup 130/Ba has been measured using sum-spectrometer techniques. The data are discussed using arguments based on particle alignments and results of cranking calculations. Jsub(band)sup((2)) and Jsub(eff)sup((2)) are compared in order to estimate the contribution of particle alignments to the total increase in angular momentum.

  15. /sup 133/Xe clearance of the knee joint of patients suffering from arthritis and osteoarthrosis

    Energy Technology Data Exchange (ETDEWEB)

    Balint, G.; Reviczky, L.A.; Lendvay, J.; Boehm, U.; Kucsera, K.; Genti, Gy. (Orszagos Reuma es Fizioterapias Intezet, Budapest (Hungary))

    1982-01-01

    65 inflammed and 13 non-inflammed knee joints of patients suffering from osteoarthrosis were examined by the Xe/sup 133/ clearance method. The control group consisted of 27 patients with exsudative arthritis of the knee. The counts of 80 ..mu..C /sup 133/Xe given intraarticcularly were measured above the knee joint by NK 350 energy selective counter. The time needed to halve the count rate measured in the 4th minute after administration (biological half life (T1/2)) was significantly different in the three groups. It was the longest in the non-inflammed arthrosis, the shortest in the exsudative arthritis group. Significant differences were apparent regarding joint pain and tenderness in all the three groups. Though the synovial protein level and the C/sub 3/ complement level were significantly different, in the three groups no relationship was found between the T1/2 and synovial/serum protein ratio or between the synovial/serum C/sub 3/ ratio. The authors concluded that /sup 133/Xe clearance, which measures the perfusion of the synovial membrane, can be used for measuring the inflammatory activity of knee joint synovitis.

  16. A 3 He-129 Xe co-magnetometer with 87 Rb magnetometry

    Science.gov (United States)

    Limes, Mark; Sheng, Dong; Romalis, Mike

    2016-05-01

    We report progress on a 3 He-129 Xe co-magnetometer detected with a 87 Rb magnetometer. The noble-gas co-magnetometer is insensitive to any long-term bias field drifts, but the presence of hot Rb can cause instability in the ratio of 3 He-129 Xe precession frequencies. We use a sequence of Rb π pulses to suppress the instability due to Rb-noble gas interactions by a factor of 104 along all three spatial axes. For detection, our 87 Rb magnetometer operates using single-axis 87 Rb π pulses with σ+ /σ- pumping-this technique decouples the 87 Rb magnetometer from bias fields, and allows for SERF operation. We are presently investigating systematic effects due to combinations of several imperfections, such as longitudinal noble gas polarization, imperfect 87 Rb π pulses, and 87 Rb pump light shifts. Thus far, our 87 Rb magnetometer has a sensitivity of 40 fT/√{Hz}, and our 3 He-129 Xe co-magnetometer has achieved a single-shot precession frequency ratio error of 20 nHz and a long-term bias drift of 8 nHz at 7 h. We are developing the co-magnetometer for use as an NMR gyro, and to search for possible spin-gravity interactions. Supported by DARPA and NSF.

  17. UV Laser Development for Dual Species Co-Magnetometer using 129Xe and 199Hg

    Science.gov (United States)

    Altiere, Emily; Hayamizu, Tomohiro; Miller, Eric; Wienands, Joshua; Madison, Kirk; Momose, Takamasa; Jones, David

    2016-09-01

    The new ultracold neutron (UCN) facility under development at TRIUMF will introduce a dual co-magnetometer with cohabiting 129Xe and 199Hg for measuring the neutrons electric dipole moment (nEDM). By simultaneously incorporating two atomic species we can characterize both the magnitude and gradient of the magnetic field, thereby lowering the systematic uncertainties in the nEDM measurement. Toward this end, the spin precession of polarized 129Xe is detected by measuring the fluorescence decay following the spin-selective two-photon transition at 252-nm 5p6(1S0) -> 5p5(2P3 / 2) 6p. As there is no suitable commercial high power laser at 252 nm, we have built an optically pumped semiconductor laser with two stages of resonant frequency doubling to produce 320 mW at 252 nm. Further increase in the power, up to 7.5 W, is achieved via a 252 nm enhancement cavity. The precession of the second atomic source, 199Hg, is detected by absorption of 253-nm from the 6s2(1S0) -> 6s6p(3P1). We have constructed an analogous laser system as the 129Xe laser but at 253-nm. In this talk I will present the construction and characterization of these two laser systems.

  18. Detection of (133)Xe from the Fukushima nuclear power plant in the upper troposphere above Germany.

    Science.gov (United States)

    Simgen, Hardy; Arnold, Frank; Aufmhoff, Heinfried; Baumann, Robert; Kaether, Florian; Lindemann, Sebastian; Rauch, Ludwig; Schlager, Hans; Schlosser, Clemens; Schumann, Ulrich

    2014-06-01

    After the accident in the Japanese Fukushima Dai-ichi nuclear power plant in March 2011 large amounts of radioactivity were released and distributed in the atmosphere. Among them were also radioactive noble gas isotopes which can be used as tracers to test global atmospheric circulation models. This work presents unique measurements of the radionuclide (133)Xe from Fukushima in the upper troposphere above Germany. The measurements involve air sampling in a research jet aircraft followed by chromatographic xenon extraction and ultra-low background gas counting with miniaturized proportional counters. With this technique a detection limit of the order of 100 (133)Xe atoms in liter-scale air samples (corresponding to about 100 mBq/m(3)) is achievable. Our results provide proof that the (133)Xe-rich ground level air layer from Fukushima was lifted up to the tropopause and distributed hemispherically. Moreover, comparisons with ground level air measurements indicate that the arrival of the radioactive plume at high altitude over Germany occurred several days before the ground level plume.

  19. Crystal structure of XeF/sup +/AsF/sub 6//sup -1/

    Energy Technology Data Exchange (ETDEWEB)

    Zalkin, A.; Ward, D.L.; Biagioni, R.N.; Templeton, D.H.; Bartlett, N.

    1978-05-01

    Crystals of XeF/sup +/AsF/sub 6//sup -/ are monoclinic, space group P2/sub 1//n, a = 6.308 (3) A, b = 6.275 (3) A, c = 16.023 (5) A, ..beta.. = 99.97 (5)/sup 0/, V = 624.66 A/sup 3/, Z = 4, and d/sub x/ = 3.61 g cm/sup -3/, at 24/sup 0/C. X-ray diffraction data were measured with counter methods and Mo K..cap alpha.. radiation. With anisotropic temperature factors for all atoms, R = 0.033 for 777 independent reflections (I greater than 3 sigma). The structure consists of ion pairs connected by a bridging fluorine atom into FXeFAsF/sub 5/ units. The FXeF portion of the molecule is linear (angle = 178.9 (7)/sup 0/) with Xe--F = 1.873 (6) A (terminal) and 2.212 (5) A (bridging). The FAsF/sub 5/ portion of the molecule is roughly octahedral with cis F--As--F angles ranging from 85.3 (3) to 94.6 (5)/sup 0/; the five terminal As--F distances range from 1.676 (5) to 1.690 (8) A and the bridging As--F distance is 1.813 (6) A. The bridge Xe--F--As angle is 134.8 (2)/sup 0/. 6 tables, 4 figures, 24 references.

  20. Total spectral radiant flux measurements on Xe excimer lamps from 115 nm to 1000 nm

    Science.gov (United States)

    Trampert, Klaus E.; Paravia, Mark; Daub, Rüdiger; Heering, Wolfgang

    2007-06-01

    Xe excimer lamps are used as VUV source for industrial application like surface cleaning. To determine the VUV efficiency of the lamp the radiant flux need to be known. Due to the difficulties of VUV measurements, it is often determined by interpolation from a value of a fixed angle, which results in large uncertainties. Here a goniometric setup is presented to measure the radiant flux of VUV sources like Xe excimer lamps which emit a narrow spectral band in the VUV range between λ = 147 nm and 200 nm with a peak at 172 nm and spectral lines in NIR. By the use of two monochromators, we measure the spectral resolved radiant flux from 120 nm to 1000 nm. The measurement uncertainty of 9.7 % is rather low for the VUV spectral range and depends mainly on the uncertainty of the used deuterium calibration standard from PTB (7%). Due to the strong temperature dependence of the transmission edge of silica used for the lamp vessel, the measurements are done in nitrogen atmosphere to ensure the convection cooling of the lamp. We measured the radiance distribution curve and radiant flux of Xe excimer lamps and could show the angle dependence of the spectrum. The measured correlation between the VUV band and the NIR lines gives us a better understanding of the plasma kinetics, which is used to optimize the pulsed excitation of the lamp.