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991.
Furutachi H Hashimoto K Nagatomo S Endo T Fujinami S Watanabe Y Kitagawa T Suzuki M 《Journal of the American Chemical Society》2005,127(13):4550-4551
A mononuclear iron(III) complex containing a peroxocarbonate ligand, [Fe(qn)2(O2C(O)O)]- (qn = quinaldinate), underwent the reversible O-O bond cleavage and reformation of the peroxo group via the formation of FeIV=O or FeV=O species, which was confirmed by the resonance Raman and ESI-TOF/MS measurements. 相似文献
992.
Stereoselective hydrothiolation of alkynes catalyzed by cesium base: facile access to (Z)-1-alkenyl sulfides 总被引:2,自引:0,他引:2
Treatment of alkyne with alkanethiol in the presence of a catalytic amount of cesium carbonate and a radical inhibitor in DMSO provides the corresponding adduct, (Z)-1-alkenyl alkyl sulfide, in good yield with high selectivity. 相似文献
993.
Kowalczyk P Tanaka H Kaneko K Terzyk AP Do DD 《Langmuir : the ACS journal of surfaces and colloids》2005,21(12):5639-5646
Grand canonical Monte Carlo (GCMC) simulation was used for the systematic investigation of the supercritical methane adsorption at 273 K on an open graphite surface and in slit-like micropores of different sizes. For both considered adsorption systems the calculated excess adsorption isotherms exhibit a maximum. The effect of the pore size on the maximum surface excess and isosteric enthalpy of adsorption for methane storage at 273 K is discussed. The microscopic detailed picture of methane densification near the homogeneous graphite wall and in slit-like pores at 273 K is presented with selected local density profiles and snapshots. Finally, the reliable pore size distributions, obtained in the range of the microporosity, for two pitch-based microporous activated carbon fibers are calculated from the local excess adsorption isotherms obtained via the GCMC simulation. The current systematic study of supercritical methane adsorption both on an open graphite surface and in slit-like micropores performed by the GCMC summarizes recent investigations performed at slightly different temperatures and usually a lower pressure range by advanced methods based on the statistical thermodynamics. 相似文献
994.
[reaction: see text] Nickel-catalyzed alkylation of aldehydes with trialkylboranes proceeds smoothly in the presence of a catalytic amount of 5-allyl-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene or an excess of cesium carbonate to afford the corresponding secondary alcohols. 相似文献
995.
S. Garcia-Ferreira A. H. Tomita S. Watson 《Proceedings of the American Mathematical Society》2005,133(3):937-943
We prove that the existence of a selective ultrafilter on implies the existence of a countably compact group without non-trivial convergent sequences all of whose powers are countably compact. Hence, by using a selective ultrafilter on , it is possible to construct two countably compact groups without non-trivial convergent sequences whose product is not countably compact.
996.
Han Z Fujioka T Usugi S Yorimitsu H Shinokubo H Oshima K 《Organic & biomolecular chemistry》2005,3(9):1622-1623
Treatment of alpha, beta-unsaturated carbonyl compounds or methyl propargyl ether with acylchlorobis(cyclopentadienyl)titanium in the presence of triethylamine and a copper salt in aqueous THF resulted in acylation of the carbon-carbon multiple bond, yielding the corresponding 1,4-diketones in good yields. 相似文献
997.
998.
999.
Yatsuyanagi Y Kiwamoto Y Tomita H Sano MM Yoshida T Ebisuzaki T 《Physical review letters》2005,94(5):054502
Dynamics of two-sign point vortices in two-dimensional circular boundary is examined by numerical simulations with MDGRAPE-2. The vortex system is characterized by the inverse temperature beta as determined from the density of states of the microcanonical ensemble of numerically generated 10(7) states. The massive simulation shows that different configurations appear in the time-asymptotic state depending on the sign of beta. Condensation of the same-sign vortices is observed when beta<0, while the both-sign vortices tend to be uniformly neutralized when beta>0. During the condensation, a part of the vortices gains energy to form clumps (patches), and the other part of the vortices loses energy to keep the total energy constant and mixes with vortices of the other sign. This observation demonstrates a characteristic feature of negative beta states that the system energy concentrates into the clumps of the same-sign vortices. 相似文献
1000.
Effects of pu-erh tea on lipid metabolism in rats 总被引:2,自引:0,他引:2
M Sano Y Takenaka R Kojima S Saito I Tomita M Katou S Shibuya 《Chemical & pharmaceutical bulletin》1986,34(1):221-228