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111.
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Masaaki Yamagishi 《Journal of Quantitative Spectroscopy & Radiative Transfer》1976,16(6):543-548
Measurements of relative intensities of spectral lines and of plasma parameters have been carried out in an Ar-O2 d.c. glow discharge under the following conditions: gas pressures of 1, 2 and 3 torr and partial pressures for O2 of 0, 0.01, 0.02, 0.05 and 0.1 torr. Many of the Ar line intensities decreased when O2 was added, while some were enhanced. Enhancement of the 6677A and 7504A lines has been most notable. The number density of metastable Ar atoms is decreased when O2 is added. Upon addition of O2, the electron temperature is decreased and the electron density increased, except at a gas pressure of 1 torr; the electric field strength in the positive column is also increased. 相似文献
114.
The degeneracy in the Heisenberg model of the three chromium clusters having D3 symmetry is split by the antisymmetric exchange interaction. Based on this new energy level scheme, the low temperature behavior of the specific heat and magnetic susceptibility are reexamined. 相似文献
115.
Masaaki Ito 《Physics letters. A》1984,104(5):248-250
A recursion operator for the classical Boussinesq equation is given, which yields infinitely many symmetries and conservation laws. It is also shown that these symmetries define a hierarchy of the classical Boussinesq equation each of which is a hamiltonian system. 相似文献
116.
Hamao Watanabe Kazuaki Higuchi Tomoko Goto Tsutomu Muraoka Jun Inose Masaaki Kageyama Yasuko Iizuka Masakatsu Nozaki Yoichiro Nagai 《Journal of organometallic chemistry》1981,218(1):27-39
In the presence of a catalytic amount of sodium methoxide, sym-dimethoxytetramethyldisilane was converted into α,ω-dimethoxypermethylpolysilanes, MeO(SiMe2)nOMe where n ? 3, at room temperature. On the other hand, similar treatment of the disilane in THF solution gave cyclic polysilanes, (Me2Si)n where n = 5–7. Decomposition of the disilane in the presence of diphenylacetylene afforded a trisilacyclopentene derivative under similar conditions. This compound was obtained also by the reaction between α,ω-dimethoxypermethylpolysilanes and diphenylacetylene in the presence of sodium methoxide. These cyclic products most likely were formed via permethyl polysilyl anion intermediates derived from α,ω-dimethoxypermethylpolysilanes. Also, the formation of α,ω-dimethoxypermethylpolysilanes could be elucidated in terms of the mechanism involving the base-assisted, concerted nucleophilic substitution or stepwise substitution by silyl anions, rather than the successive dimethylsilylene (Me2Si:) insertion reaction. 相似文献
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Sekiguchi A Inoue S Ichinohe M Arai Y 《Journal of the American Chemical Society》2004,126(31):9626-9629
The highly twisted tetrakis(di-tert-butylmethylsilyl)disilene 4 was prepared and reacted with (t)BuLi in THF, producing disilene anion radical 5 upon one-electron reduction. The anion radical 5 was isolated in the form of its lithium salt as extremely air- and moisture-sensitive red crystals. The molecular structure of 5 was established by X-ray crystallography, which showed a nearly orthogonal structure (twisting angle of 88 degrees ) along the central Si-Si bond, with a length of 2.341(5) A, which is 3.6% elongated relative to that of 4. The interesting feature of 5 is that one of the central Si atoms has radical character, whereas the other Si atom has silyl anion character. An electron spin resonance (ESR) study of the hyperfine coupling constants of the (29)Si nuclei indicates that rapid spin exchange occurs between these central Si atoms on the ESR time scale. 相似文献
120.
A series of trinuclear Cu(II)Ln(III)Cu(II) complexes with the bridging ligand 2,6-di(acetoacetyl)pyridine have been prepared by one-pot reaction with Cu(NO(3))(2).3H(2)O and Ln(NO(3))(3).nH(2)O in methanol. X-ray crystallographic studies for all the complexes indicate that two L(2)(-) ligands selectively sandwich two Cu(II) ions with the 1,3-diketonate entities and one Ln(III) ion with the 2,6-acetylpyridine entity to form a trinuclear CuLnCu core bridged by the enolate oxygen atoms. Cryomagnetic properties of the complexes are studied with respect to the electronic structure of the Ln ion. 相似文献