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51.
H. Sato A. Tani A. J. Fielding S. S. Eaton G. R. Eaton N. E. Whitehead M. Ikeya 《Applied magnetic resonance》2004,26(4):601-616
Nitrate radical NO32− in calcitic evaporate was discovered in Antarctica. The distribution and formation of nitrate radical NO32− in the calcite have been studied by pulse and continuous-wave electron spin resonance. In samples that had been annealed
to destroy the NO32−, regeneration of the radical by γ-rays or UV light indicated that the radical was formed by UV light (with wavelengths less
than 340 nm) from solar rays, not by environmental radiation. The nonuniform spatial distribution of the nitrate radical,
which was deduced from high ratios of local spin density to total spin density, suggests that the nitrate impurity was introduced
into the calcium carbonate after carbonate grain formation. Formation of the carbonate-containing nitrate requires the presence
of high amounts of nitrate and a dry climate. Formation of the nitrate radical requires sample exposure to UV light. These
conditions are satisfied in the environment of Antarctica. 相似文献
52.
53.
The motion of a moored floating body under the action of wave forces, which is influenced by fluid forces, shape of the floating body and mooring forces, should be analysed as a complex coupled motion system. Especially under severe storm conditions or resonant motion of the floating body it is necessary to consider finite amplitude motions of the waves, the floating body and the mooring lines as well as non-linear interactions of these finite amplitude motions. The problem of a floating body has been studied on the basis of linear wave theory by many researchers. However, the finite amplitude motion under a correlated motion system has rarely been taken into account. This paper presents a numerical method for calculating the finite amplitude motion when a floating body is moored by non-linear mooring lines such as chains and cables under severe storm conditions. 相似文献
54.
M. Sato 《等离子体物理论文集》1991,31(3):331-335
The Saha equation for a plasma in thermodynamic equilibrium (TE) is approximately solved to give the temperature as an explicit function of population densities. It is shown that the derived expressions for the Saha temperature are valid approximations to the exact solution. An application of the approximate temperature to the calculation of TE plasma parameters is also described. 相似文献
55.
This paper proposes a two step algorithm for solving a large scale semi-definite logit model, which is appreciated as a powerful
model in failure discriminant analysis. This problem has been successfully solved by a cutting plane (outer approximation)
algorithm. However, it requires much more computation time than the corresponding linear logit model. A two step algorithm
to be proposed in this paper is intended to reduce the amount of computation time by eliminating a certain portion of the
data based on the information obtained by solving an associated linear logit model. It will be shown that this algorithm can
generate a solution with almost the same quality as the solution obtained by solving the original large scale semi-definite
model within a fraction of computation time. 相似文献
56.
Takuji Sato 《Proceedings of the American Mathematical Society》2003,131(9):2903-2909
We obtain a non-Kähler almost Hermitian manifold of constant holomorphic sectional curvature by changing the almost complex structure in a Kähler manifold of constant holomorphic sectional curvature.
57.
H. Sato A. Bensalah N. Solovieva A. Beitlerova A. Vedda M. Martini M. Nikl T. Fukuda 《Radiation measurements》2004,38(4-6):463-466
Two-inch sized KMgF3,BaLiF3 and LiCaAlF6 (LiCAF) single crystals were grown by the Czochralski method under a CF4 atmosphere. X-ray irradiation was used to carry out a comparative study of induced optical absorption phenomena and colour centre creation in the ultra-violet and visible spectral regions. The integral of the induced absorption spectra is significantly lower in LiCAF with respect to the other studied materials. It is found that the amplitude of the F-absorption band is suppressed more than a factor of 3 by Mg-doping. For Mg-doped crystals, the optimum doping concentration is about 0.2 mol% of Mg2+. 相似文献
58.
Recently, a remarkable technique to overcome the problem of light-induced degradation in amorphous silicon (a-Si) solar cells using a cyanide (CN) treatment has been developed. Structural and bonding characteristics of CN in a-Si has been studied using ab initio molecular dynamics simulations. It was found that CN incorporation results in more than just the termination of dangling bonds. The connectivity of the covalent random network increases because the CN changes from triply bonded, which is a common form in molecular CN, to the singly bonded form. This may be the mechanism by which CN incorporation produces significant reductions in light-induced degradation. 相似文献
59.
A. Ikegami Y. Kimura H. Suzuki T. Sato T. Tanigaki O. Kido M. Kurumada Y. Saito C. Kaito 《Surface science》2003,540(2-3):395-400
Titanium carbide formation by the solid–solid reaction on the surface of Ti nanoparticles was studied in situ using a high-resolution transmission electron microscope with a heating stage. The cross-sectional image of the Ti surface was clearly observed. Vacuum-deposited carbon covered the whole the surface of Ti nanoparticles in spite of the partly evaporation on the nanoparticle surface. The diffusion of the carbon atoms inside the Ti nanoparticles depended on the size of the nanoparticles. When the Ti nanoparticle diameter was less than 30 nm, carbon atoms diffused into the Ti nanoparticle and formed TiC. The superstructure of the Ti nanoparticles was observed, which revealed the growth process of TiC to be the diffusion of carbon atoms. For Ti nanoparticles with diameter larger than 30 nm it was observed that diffusion of Ti atoms into the carbon layer was dominant, which resulted in formation of TiC in the carbon layer at the surface of Ti nanoparticles. 相似文献
60.
Hiroshi Sugimoto Hiromitsu Ohshima Shohei Inoue 《Journal of polymer science. Part A, Polymer chemistry》2003,41(22):3549-3555
The first successful example of the formation of polycarbonate from 1-atm carbon dioxide and epoxide was demonstrated by the alternating copolymerization of carbon dioxide and epoxide with manganese porphyrin as a catalyst. The copolymerization of carbon dioxide and cyclohexene oxide with (porphinato)manganese acetate proceeded under the 1-atm pressure of carbon dioxide to give a copolymer with an alternating sequence. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3549–3555, 2003 相似文献