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The results of studies of the reactions of ruthenium and osmium cluster carbonyls with metal alkynes, silylalkynes, propargyl alcohols and their derivatives, diynes, enynes, and ferrocenylacetylene are summarized. Intramolecular rearrangements in the cluster complexes including migrations of carbonyl, hydride, and hydrocarbon ligands as well as the metal core reorganization are considered. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 1–17, January, 2000.  相似文献   
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AK Banerjee  MN Alam  AA Mamun 《Pramana》2001,56(5):643-656
Obliquely propagating altra-low-frequency dust-electromagnetic waves in a self-gravitating, warm, magnetized, two fluid dusty plasma system have been investigated. Two special cases, namely, dust-Alfvén mode propagating parallel to the external magnetic field and dustmagnetosonic mode propagating perpendicular to the external magnetic field have also been considered. It has been shown that effects of self-gravitational field, dust fluid temperature, and obliqueness significantly modify the dispersion properties of these ultra-low-frequency dust-electromagnetic modes. It is also found that in parallel propagating dust-Alfvén mode these effects play no role, but in obliquely propagating dust-Alfvén mode or perpendicular propagating dust-magnetosonic mode the effect of self-gravitational field plays destabilizing role whereas the effect of dust/ion fluid temperature plays stabilizing role.  相似文献   
64.
Rhodium and iridium complexes of a new ferrocene-derived bis(N-heterocyclic carbene) ligand, [M(cod){1,2-(MeNCHCHNCCH(2))(2)C(5)H(3)}Fe(C(5)H(5))]BF(4) (M = Rh, 8a; M = Ir, 8b; cod = 1,5-cyclooctadiene), were synthesized from the corresponding bis(imidazolium) salt 6. The molecular structure of 8a was determined by single-crystal X-ray diffraction. Complexes 8a and 8b smoothly react with CO with displacement of the chelating cod ligand to give the corresponding dicarbonyl derivatives 9a and 9b.  相似文献   
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The reaction of [CpRu(CH3CN)3][PF6], [Cp*RuCl] n , and [CpFRuCl]n with 1,3-diformylindene results in the predominant formation of zwitter-ionic arene-cyclopentadienyl complexes {η6-1,3-(CHO)2C9H5}RuCp (Cp = C5H5), {η6-1,3-(CHO)2C9H5}RuCp* (Cp* = C5Me5), and {η6-1,3-(CHO)2C9H5}RuCpF (CpF = C5Me4CF3), respectively. The ruthenocenes {η5-1,3-(CHO)2C9H5}RuCp, {η5-1,3-(CHO)2C9H5}RuCp*, and {η5-1,3-(CHO)2C9H5}RuCpF were synthesized by the reaction of 1,3-diformylindenyl potassium with [CpRu(CH3CN)3][PF6], [Cp*RuCl] n , and [CpFRuCl] n .  相似文献   
66.
Modes of formation, structural features, reactivities, and stereochemical nonrigidity of cluster carbonyl complexes with acetylide ligands are considered. Published inIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 7, pp. 1141–1167, July, 2000.  相似文献   
67.
It is shown how one can transform scalar first-order ordinarydifferential equations which admit non-local symmetries of theexponential type to integrable equations admitting canonicalexponential non-local symmetries. As examples we invoke theAbel equation of the second kind, the Riccati equation and naturalgeneralizations of these. Moreover, our method describes howa double reduction of order for a second-order ordinary differentialequation which admits a two-dimensional Lie algebra of generatorsof point symmetries can be affected if the second-order equationis first reduced in order once by a symmetry which does notspan an ideal of the two-dimensional Lie algebra.  相似文献   
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Piezoelectricity is usually expressed as an interaction between mechanical and electrical variables. The physics involved is hence governed by a coupling between Maxwell's equations of electromagnetism and the equations of elasticity. Such a coupling takes us through the piezoelectric constitutive relations. In this work, the second order anisotropic constitutive equations are treated, and in particular, the number of independent material constants is computed for all the 32 crystallographic classes.Paper presented, in reduced version, at the 12th Italian National Congress of Theoretical and Applied Mechanics (AIMETA '95), October 1995, Naples, Italy.  相似文献   
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