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991.
Farsighted stability is examined in an n-person prisoner’s dilemma. It is shown that any individually rational and Pareto efficient outcome is a farsighted stable set and no other farsighted stable set exists; it is further shown that the largest consistent set consists of all individually rational outcomes. 相似文献
992.
An ion cyclotron drift instability is excited by a cross field current due to Er × B drift of electrons and ion heating is observed in a plasma column in a magnetic field when a dc radial electric field Er is applied. 相似文献
993.
Kiyoshi Bannai Takeshi Toru Takeo Ba Toshio Tanaka Noriaki Okamura Kenzo Watanabe Seizi Kurozumi 《Tetrahedron letters》1981,22(15):1417-1420
Stable analogues of PGI2, 7-hydroxy- and 7-acetoxy-PGI2, were synthesized from protected PGI2 methyl ester via sulfoxides , through stereocontrolled sulfoxide-sulfenate rearrangement. 相似文献
994.
995.
Tetrathiafulvalen (TTF) and tetraselenafulvalen (TSF) salts with diorganochloro-stannate anions, [TTF][SnEt2Cl3] (1), [TTF]2[SnPh2Cl4] (2), [TTF]3[SnEt2Cl4] (3), [TTF]3.3[SnPh2Cl4] (4), [TSF]2[SnPh2Cl4] (5) and [TSF]3.3[SnPh2Cl4] (6), were prepared by the reactions of [TTF or TSF]3[BF4]2 with SnR2Cl2 (R = Et or Ph) in the presence of [Ph3PCH2Ph]Cl and by electrocrystallization of TTF or TSF in acetonitrile containing SnR2Cl2 and [Ph3PCH2Ph]Cl. All the salts behave as semiconductors with electrical resistivities of the order of 10–108 Ω cm as compacted samples at 25°C. Electronic reflectance spectra of the simple salts 1, 2 and 5, show a band due to the dimeric(TTF+)2 or (TSF+)2 unit in the 12,200–12,800-cm?1 region. The complex salt 3 exhibits a TTF+/TTF° charge-transfer (CT) band at 8700 cm?1, and the remaining complex salts, 4 and 6, both display CT bands between the radical cations and between the radical cation and the neutral donor molecule. The crystal structure of 3 was determined by a single-crystal X-ray diffraction. The tetragonal crystal, space group I4cm, has cell dimensions a = 11.710(3) Å, c = 25.242(7) Å, and Z = 4. The structure was solved by the heavy-atom method and refined to a final R value of 0.082 for 479 independent reflections with >F° > 3σ(F). TTF molecules exist as trimers, in which a slight lateral shift from the eclipsed TTF overlap occurs, although TTF molecules are arranged with equal spacing between them. The trimer units are located perpendicularly to each other, forming a two-dimensional layer. The [SnEt2Cl4]2? anion is disordered with respect to the two SnEt and two SnCl bonds. 相似文献
996.
Raman spectra are presented in the high and low temperature phases of 2H-TaS2. In the normal phase at 380 K one A1g- and two E2g-modes have been observed at 400, 27 and 286 cm-1, respectively. In the charge density wave state two extra peaks appear with strong scattering intensity in E2g- symmetry and weak in A1g-symmetry. The E2g peak grows and hardens toward 50 cm-1 with decreasing temperature. The temperature dependence is very similar to the E2g-mode in 2H-TaSe2 of similar 3a0 × 3a0 superstructure. Other peaks observed in 2H-TaSe2 in the commensurate phase are not observed. This suggests the incommensurability of the charge density wave state in 2H-TaS2. 相似文献
997.
Displacement measurements by laser-homodyne or laser-heterodyne methods are dicussed analytically with respect to the relevant surface roughness. Expressions of the output signal and its signal-to-noise ratio are derived on the basis of gaussian statistics of the roughness. The roughness does not impose restrictions on the measurable minimum displacement but degrades the signal-to-noise ratio of the output signal. 相似文献
998.
999.
1000.
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