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81.
We theoretically discuss X-ray absorption intensity in high-energy region far from the deepest core threshold to explain the morphology-dependent mass attenuation coefficient of some carbon systems, carbon nanotubes (CNTs), highly oriented pyrolytic graphite (HOPG) and fullerenes (C60). The present theoretical approach is based on the many-body X-ray absorption theory including the intrinsic losses (shake-up losses). In the high-energy region the absorption coefficient has correction term dependent on the solid state effects given in terms of the polarization part of the screened Coulomb interaction Wp. We also discuss the tail of the valence band X-ray absorption intensity. In the carbon systems C 2s contribution has some influence on the attenuation coefficient even in the high energy region at 20 keV. 相似文献
82.
Misato Kazama Hiroshi Shinotsuka Takashi Fujikawa Mauro Stener Piero Decleva Jun-ichi Adachi Tomoya Mizuno Akira Yagishita 《Journal of Electron Spectroscopy and Related Phenomena》2012
1s photoelectron angular distributions from fixed-in-space CO2, NO2, BF3 and CH3F molecules have been calculated by X-ray photoelectron diffraction (XPD) theory with muffin-tin-type molecular potential. For all the molecules, the calculated results show good agreements with those by density functional theory in the energy region ?100 eV. Furthermore, for all the molecules experimental data on the angular distributions in such energy region are well reproduced by the XPD theory. These intensive studies lead to a rather general rule that the XPD theory is an adequate tool to describe high-energy photoelectron angular distributions for any single oriented molecules. 相似文献
83.
84.
K. Uchida T. Ota K. Harii S. Takahashi S. Maekawa Y. Fujikawa E. Saitoh 《Solid State Communications》2010,150(11-12):524-528
The spin-Seebeck effect (SSE) converts a heat current into a spin current, a flow of spin angular momentum, and spin voltage, the driving force for nonequilibrium spin currents, in a ferromagnetic metal. In this study, the SSE in a ferromagnetic Ni81Fe19 film has been investigated by means of the inverse spin-Hall effect (ISHE) in a Pt film at room temperature. The experimental results measured in the Ni81Fe19/Pt system show that the sign of the thermally induced spin voltage is reversed between the higher- and lower-temperature ends of the Ni81Fe19 film. The ISHE in the Pt film allows us to detect the SSE signal with high sensitivity and to separate it from extrinsic thermoelectric effects. 相似文献
85.
We present low energy electron microscope (LEEM) spectromicroscopy studies of surface plasmons, localized on micro- and nanoscale epitaxial Ag islands. Excellent agreement is found in a direct comparison of wave vector dependent plasmon intensity with theory, demonstrating that high quality quantitative data can be obtained with a large improvement in both spatial and temporal resolution over traditional electron scattering experiments. The plasmon signal from Ag islands is successfully imaged with a spatial resolution of less than 35 nm. LEEM based plasmon spectromicroscopy promises to be a powerful tool for furthering our understanding of nanoplasmonics. 相似文献
86.
Filmwise non-equilibrium condensation of methanol vapour is investigated on a shock-tube endwall behind a reflected shock wave. The theoretical prediction of a transition phenomenon during the growth of a liquid film is experimentally demonstrated: the film grows approximately in proportion to the time at the early stages after the reflection of the shock wave and, after a transition period, it grows in proportion to the square root of the time. The condensation parameter of the vapour is obtained from the conformity between experiment and theory. It is found that the condensation parameter of the methanol vapour is of the magnitude of one tenth of the value for the complete capture of the molecules on the liquid surface. 相似文献
87.
Takashi Fujikawa 《Journal of Electron Spectroscopy and Related Phenomena》1981,22(3):353-364
Angle-resolved photoemission from deep core orbitals on irradiation with soft X-rays is theoretically considered and compared with EXAFS results. Numerical calculations are carried out for ionization from the 1s orbital of O adsorbed on an Al (110) surface, and the results show that the variations of the differential photoionization cross-section in special directions are rapid in comparison with that given by EXAFS with respect to final kinetic-energy variation. 相似文献
88.
Determination of trace amounts of heavy metals in arctic ice core samples using inductively coupled plasma mass spectrometry 总被引:2,自引:0,他引:2
Trace amounts of heavy metals in the ice cores from Canadian Arctic were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). A custom made plastic device and ceramic knives were used to remove the contamination on the ice core surface. Ice cores could be broken into small sections (2-3 cm thick) after decontamination with the plastic device and ceramic knives. High-resolution depth profiles of various elements, i.e. As, Cd, Co, Cu, Ni, Pb, Zn and U, were thus attained. Concentrations in 518 ice core samples range from 0.1 (U) to 673.3 (Zn) pg g(-1). 相似文献
89.
Ho Sik Kim Yoshihisa Kurasawa Chiemi Yoshii Minako Masuyama Atsushi Takada Yoshihisa Okamoto 《Journal of heterocyclic chemistry》1990,27(4):1115-1117
The reaction of the 2-substituted 6-chloroquinoxaline 4-oxides 1a or 1b with 2-fold molar amount of methyl propiolate resulted in the 1,3-dipolar cycloaddition reaction to give 8-chloro-1,3-bismethoxycarbonyl-4-(piperidin-1-yl)pyrrolo[1,2-a]quinoxaline 4a or 8-chloro-1,3-bismethoxycarbonyl-4-(morpholin-4-yl)pyrrolo-[1,2-a]quinoxaline 4b , respectively. Compound 4a or 4b was transformed into 8-chloro-3-methoxycarbonyl-4-(piperidin-1-yl)pyrrolo[1,2-a]quinoxaline 5a or 8-chloro-3-methoxycarbonyl-4-(morpholin-4-yl)pyrrolo[1,2-a]-quinoxaline 5b , respectively. The structure of 4a,b was confirmed by the NOE measurement among the C1 -H , C 2-H and C 9-H proton signals of 5a,b . An additional reaction mechanism was proposed for the ring transformation of isoxazolo[2,3-a]quinoxalines into pyrrolo[1,2-a]quinoxalines. 相似文献
90.