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61.
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The complexes [MHCl(CO)(PPh3)3] (M = Ru or Os) readily undergo substitution at the site trans to the hydride ligand to afford phosphinite-, phosphonite-, or phosphite-containing products [MHCI(CO)(PPh3)2L] [L = P(OR)Ph2, P(OR)2Ph or P(OR)3 respectively; R = Me or Et]. The ruthenium complexes alone undergo further substitution to afford complex cations [RuH(CO)(PPh3)nL4?n]+ [n = 2, L = P(OMe)3; n = 1, L = P(OR)3; n = 0, L = P(OR)2Ph or P(OR)Ph2] which were isolated and characterised as their tetraphenylborate salts. Synthesis of the cationic complexes [IrHL5][BPh4]2 [L = P(OR)3, R = Me or Et] is also reported. Stereochemical assignments based on NMR data are given, and second order 31P and high field 1H NMR patterns are analysed. 相似文献
63.
We present a phenomenological analysis of backward photoproduction in terms of the recently proposed kinematic cut model. The cut fills in the dip at u ≈ −0.15 without having to invoke the Nγ trajectory. Good agreement with the data is obtained in the scattering region; the extrapolation to the nucleon pole is unsatisfactory. 相似文献
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The PL/PK method of determining the ?-capture decay energy fails badly in the case of 113Sn. We suggest that the discrepancies in the measured values may be due to variable amounts of 250 d 119Snm present in the 115 d 113Sn samples. 相似文献
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A new stable product from the reaction of nitrosobenzene and N-ethoxycarbonylazepine is shown to be a 1,4-cycloadduct. 相似文献
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Arvind Kumar V. P. Mohandas V. R. K. S. Susarla P. K. Ghosh 《Journal of solution chemistry》2004,33(8):995-1003
Different physicochemical properties such as solubilities, densities, viscosities, and electrical conductivities of calcium sulfate dihydrate in aqueous calcium chloride solutions have been measured at 30°C to examine the ionic interactions in the system. Density values have been used to calculate the mean apparent molar volumes of ternary mixtures. Viscosity values have been analyzed using different empirical equations and the experimental values of viscosity were combined with conductivity values to get the Walden product. The experimental data have been fitted by a polynomial equation for least-squares analysis to obtain the coefficients and the standard errors. Results have been examined in the light of the structure making or structure breaking effect of the various ions present in the solution. 相似文献