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71.
The structures of the metallacarborane cations [(-9-Me2S-7,8-C2B9H10)Ni(-Cp)Ni(-9-Me2S-7,8-C2B9H10)]+ (2) and [Cp*Ru(Me2S-C2B9H10)RuCp*]+ (4b) were established by X-ray diffraction analysis. These results confirmed the triple-decker structure proposed for complex 2 earlier, whereas complex 4b proved to be 13-vertex dimetallacarborane rather than the triple-decker complex, as has been suggested earlier.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1879–1883, September, 2004.  相似文献   
72.
Compounds (η-C5R5)Fe[η-9-(Me2S)-7,8-C2B9H10] (R=H, Me) and (η-C4Me4)Co[η-9-(Me2S)-7,8-C2B9H10] were synthesized by the reactions of Na[9-(Me2S)-7,8-C2B9H10] with complexes [(η-C5H5)Fe(MeCN)3]PF6, [(η-C5Me5)Fe(MeCN)3]BF4, and [(η-C4Me4)Co(MeCN)3]PF6, respectively. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 177–179, January, 1999.  相似文献   
73.
The possibility of investigating high-temperature superconductors (HTSC) by the μSR method with negative muons is discussed in the paper. The results of measurement of the probability of negative muon capture by oxygen and residual polarization of muons in the 1s-state of oxygen in some HTSC at room temperature are reported.  相似文献   
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In this paper the relation betweenEP--matrices andE k P--matrices over an arbitrary filedF is studied. Further, conditions for the product ofE k P--matrices to be anE k P--matrix and for the reverse order law to hold for the polynomial Moore-Penrose inverse of the product ofE k P--matrices are determined  相似文献   
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The affinity of acetonitrile to different adsorbents used as modifiers of quartz crystal microbalance electrodes was estimated from quantitative sorption parameters. A piezoelectric quartz crystal microbalance with electrodes modified with a squalane solution in hexane was proposed for determining acetonitrile in air at a level of 0.5 MPC. The conditions of the formation of sensitive films (modifier weight and solvent) were optimized, and the interfering effect of alkyl acetates was studied.  相似文献   
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Many factors may affect the heavy metals sorption on natural zeolites among them the temperature, for this reason in this paper the cadmium retention behavior on Mexican zeolitic rich tuff as a function of temperature is considered. The kinetic and the isotherms were determined at 303, 318, and 333 K, the remaining cadmium in the solution samples was analyzed by atomic absorption spectrometry. The pseudo-second order rate constant, k, as well as the apparent diffusion coefficients were calculated from the cadmium uptake by the zeolitic rock as a function of the contact time and temperature, the highest amounts were found for the experiments done at 333 K. The maximum cadmium adsorption capacity by the zeolitic material was 12.2 mg Cd2+/g at 318 K corresponding to 20% of the effective ion exchange capacity of the Chihuahua zeolitic rock. In order to explain the cadmium sorption behavior different kinetics and isotherm models were considered.  相似文献   
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