排序方式: 共有117条查询结果,搜索用时 15 毫秒
21.
A. Laricchiuta D. Bruno M. Capitelli C. Catalfamo R. Celiberto G. Colonna P. Diomede D. Giordano C. Gorse S. Longo D. Pagano F. Pirani 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(3):607-612
In the perspective of higher approximations of the Chapman-Enskog theory for transport property calculations, existing transport
cross sections databases for interactions involving Earth atmosphere species have been updated and extended to Mars atmosphere
components, proposing a phenomenological approach for the derivation of the relevant elastic collision integrals in neutral-neutral
and neutral-ion interactions. Inelastic collision integrals terms, due to resonant charge exchange channels, have been considered
and the asymptotic approach extended to the estimation of charge transfer cross section of multiple resonant processes.
Electronic supplementary material Supplementary Online Material 相似文献
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C. Catalfamo D. Bruno G. Colonna A. Laricchiuta M. Capitelli 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(3):613-621
Transport coefficients of equilibrium Martian atmosphere have been calculated in the second non-vanishing Chapman-Enskog approximation
and compared with existing literature results. The present work improves previous calculations by considering a very detailed
chemistry model of Martian atmosphere that includes 53 species and by extending the temperature range up to 50 000 K. 相似文献
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Defect configurations of Ge-S binary glasses have been studied systemically by Raman scattering technique and positron annihilation lifetime spectra (PALS). The correlations between the positron lifetime data, structural features, and chemical compositions of Ge-S binary glasses have been established, and also the identification of open volume originated from coordination defects has been carried out. The cognizance of defect configuration will be very helpful to further understand the unique photosensitivity of chalcogenide glasses. 相似文献
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D. Cortina-Gil T. Baumann H. Geissel H. Lenske K. Sümmerer L. Axelsson U. Bergmann M.J.G. Borge L.M. Fraile M. Hellström M. Ivanov N. Iwasa R. Janik B. Jonson K. Markenroth G. Münzenberg F. Nickel T. Nilsson A. Ozawa K. Riisager G. Schrieder W. Schwab H. Simon C. Scheidenberger B. Sitar T. Suzuki M. Winkler 《The European Physical Journal A - Hadrons and Nuclei》2001,10(1):49-56
One-neutron removal cross-sections ( ) of 17, 19C in various targets at about 900 MeV/nucleon, and one-proton removal cross-sections ( ) of 8, 10B at about 1400 MeV/nucleon were measured using the fragment separator FRS at GSI. A significant increase of for 19C compared to its neighbors was observed. The same behavior was found for for the neutron-deficient nucleus 8B compared to the stable isotope 10B. These results support a one-neutron halo structure in 19C and a one-proton halo in 8B.
Received: 26 July 2000 / Accepted: 11 January 2001 相似文献
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Characterization of hydrogenated amorphous silicon thin films prepared by magnetron sputtering 总被引:1,自引:0,他引:1
Magnetron sputtered hydrogenated amorphous silicon (a-Si:H) thin films have been characterized. Hydrogen (H2) with argon (Ar) was introduced into the sputtering chamber to create the plasma. A sudden increase in the deposition rate occurred when the hydrogen was added. The maximum hydrogen content of 16 atomic percent (at.%) was achieved and a bandgap of about 2.07 eV was determined from the spectral investigations of the hydrogenated films. The effect of radio frequency (RF) power on the deposition rate, as well as on the hydrogen content was investigated. To change the hydrogen content in the films, the hydrogen flow rate was varied while keeping the argon flow rate constant. The hydrogen content in the films increased with increasing hydrogen flow rate up to the maximum content of 16 at.% and then decreased for further increases in hydrogen flow. 相似文献
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A systematic study of the chemical bonding in hydrogenated amorphous germanium–carbon (a-Ge1-xCx:H)alloys using X-ray photoelectron spectroscopy (XPS) is presented. The films, with carbon content ranging from 0 at. % to
100 at. %, were prepared by the rf co-sputtering technique. Raman spectroscopy was used to investigate the carbon hybridization.
Rutherford backscattering spectroscopy (RBS) and XPS were used to determine the film stoichiometry. The Ge 3d and C 1s core
levels were used for investigating the bonding properties of germanium and carbon atoms, respectively. The relative concentrations
of C–Ge, C–C, and C–H bonds were calculated using the intensities of the chemically shifted C 1s components. It was observed
that the carbon atoms enter the germanium network with different hybridization, which depends on the carbon concentration.
For concentrations lower than 20 at. %, the carbon atoms are preferentially sp3 hybridized, and approximately randomly distributed. As the carbon content increases the concentration of sp2 sites also increases and the films are more graphitic-like.
Received: 4 May 1999 / Accepted: 24 November 1999 / Published online: 24 March 2000 相似文献
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A. Dirner V. V. Glagolev J. Hlaváčová N. B. Ladygina G. Martinská J. Urbán 《The European Physical Journal A - Hadrons and Nuclei》2000,8(4):493-499
Angular distributions of spectator particles in dp and 4Hep reactions in the region of a few GeV have been studied. Significant asymmetries of the spectator particle distributions
have been observed for reactions where π-mesons are produced in the final state. Results of calculations in the framework
of a spectator model taking into account the nuclear wave function, flux factor and the energy dependence of the NN elementary
cross-sections, have been compared to experimental data. A good agreement has been observed for the fragments momenta, where
the one-pole mechanism dominates.
Received: 11 February 2000 / Accepted: 29 June 2000 相似文献