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The 86-electron dicationic octahedral rhodium cluster [Rh6Cp6(μ6-C)]2+(PF6
-)2 containing Cp ligands and the interstitial carbon atom was synthesized by the reaction of Rh3Cp3(μ-CO)3 with RhCp(C2H4)2
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 395–396, February, 1999 相似文献
114.
A. R. Kudinov A. A. Fil'chikov P. V. Petrovskii M. I. Rybinskaya 《Russian Chemical Bulletin》1999,48(7):1352-1355
The parent 30-electron triple-decker iron complex with cyclopentadienyl ligands, [(η-C5H5)Fe(μ-η:η-C5H5)Fe(η-C5H5)]PF6 (1), was prepared for the first time by visible-light irradiation of ferrocene and [(η-C5H5)Fe(η-C6H6)]PF6 in CH2Cl2 at 0 °C. An analogous reaction performed with the use of (η-C5H5)Co(η-C4Me4) (2) instead of ferrocene afforded the thermally labile 30-electron cationic iron-cobalt triple-decker complex [(η-C5H5)Fe(μ-η:η-C5H5)Co(η-C4Me4)]PF6. The latter reacted with compound 2 at 20 °C to form the symmetrical 30-electron cationic dicobalt triple-decker complex
[(η-C4Me4)Co(μ-η:η-C5H5)Co(η-C4Me4)] PF6.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya. No. 7, pp. 1364–1367, July, 1999. 相似文献
115.
A. R. Kudinov P. V. Petrovskii V. I. Meshcheryakov M. I. Rybinskaya 《Russian Chemical Bulletin》1999,48(7):1356-1361
The previously unknown metallacarboranes (η-C5R5)Ru(η-9-Me2S-7,8-C2B9H10) (R=H or Me) and (η-C5H5)Ni(η-9-Me2S-7,8-C2B9H10) were prepared and used in the synthesis of the first metallacarborane triple-decker complexes with a central cyclopentadienyl
ligand, viz., [(η-C5R5)Ru(μ-η:η-C5Me5)Ru(η-9-Me2S-7,8-C2B9H10)]PF6 (R=H or Me), [(η-9-Me2S-7,8-C2B9H10)Ni(μ-η:η-C5H5)Ni(η-9-Me2S-7,8-C2B9H10)]PF6, and [(η-C5H5)Ni(μ-η:η-C5H5)Ni(η-9-Me2S-7,8-C2B9H10)]BF4.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1368–1373, July, 1999. 相似文献
116.
M.K. Islam S. Biswas N.A. Chowdhury A. Mannan M. Salahuddin AA Mamun 《等离子体物理论文集》2022,62(1):e202100073
A theoretical investigation has been carried out on the propagation of non-linear ion-acoustic shock waves (IASHWs) in a magnetized degenerate quantum plasma system composed of inertial non-relativistic positively charged light and heavy ions, inertialess non-relativistically or ultra-relativistically degenerate electrons and positrons. The reductive perturbation method has been employed to derive the Burgers' equation. It has been observed that under consideration, our plasma model supports only positive potential shock structure. It is also found that the amplitude and steepness of the IASHWs have been significantly modified by the variation of ion kinematic viscosity, oblique angle, number density, and charge state of the plasma species. The results of our present investigation will be helpful for understanding the propagation of IASHWs in white dwarfs and neutron stars. 相似文献
117.
Commensurability between inter-vortex distance and crystal lattice constant is investigated by angular dependent magnetization
in very pure twinned and twin-free NdBa2 Cu3 Oy single crystals. With increasing temperature the incommensurate states split up and become finally commensurate with half
the vortex distance. These new commensurate states are related to a substructure of the intrinsic pinning potential within
the unit cell and discussed with respect to temperature, field, anisotropy, and twin structure. 相似文献
118.
MJ Lazaro AA Herod M Domin Y Zhuo CA Islas R Kandiyoti 《Rapid communications in mass spectrometry : RCM》1999,13(14):1401-1412
Three methods for determining a 'safe' estimate for high-mass limits of MALDI spectra of coal derived liquids were explored, using a sample of coal-tar pitch and its pyridine-insoluble fraction. Co-addition of increasing numbers of single-shot spectra (10, 30, 50 and 100 pulses) showed visually observable reductions in noise levels, consistent with robust and statistically meaningful signals. Three separate types of post-acquisition calculation were used to identify high-mass limits of the spectra. (i) A literature method indicated high-mass limits similar to those observed visually-as a shift from baseline at the highest masses, nearly 350 000 u for the coal tar pitch and about 390 000 u for its pyridine insoluble fraction. (ii) Comparing instrument signal with pre-selected multiples of the standard deviation, upper mass estimates of between 40-60 000 u for the coal-tar pitch and about 95 000 u for its pyridine-insoluble fraction were found. (iii) Calculation of the slope was used to identify 'lift-off' of the spectrum from baseline. The angle between the smoothed spectrum and the baseline was matched to a pre-selected value (e.g. 0.5 degrees and 1 degrees ). However, the arbitrary specification of the key parameter did not establish this last method on a firm basis. The choice of a criterion for estimating high-mass limits of MALDI spectra remains a semi-quantitative procedure; a reasonably conservative high-mass limit may be estimated by comparison of signal with five times the standard deviation. However, evaluation of size exclusion chromatograms of the present samples using polystyrene standards suggests that molecular mass distributions of pitch samples arrived at by MALDI mass spectrometry are, at least partly, determined by the limitations of available instruments. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
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