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661.
Alexander JS Allis DG Hudson BS Ruhlandt-Senge K 《Journal of the American Chemical Society》2003,125(49):15002-15003
A powerful new synthetic method allows for the exploration of an interesting class of rubidium diphenylmethanides showing different solid-state modifications depending on the crystallization temperatures. Theoretical and structural analysis in the solution and the solid state leads to a broader understanding of metal-ligand binding modes. 相似文献
662.
Burkhart BE Gopalkrishnan PV Hudson SD Jamieson AM Rother MA Davis RH 《Physical review letters》2001,87(9):098304
The evolution of the drop-size distribution in immiscible fluid mixtures following well-specified shear histories is investigated by in situ microscopy, allowing determination of the shear-induced coalescence efficiency epsilon. At small capillary number Ca, epsilon is constant, whereas at larger values of Ca, epsilon decreases, in agreement with theory accounting for slight deformation of the drops in close approach. Coalescence causes the drop-size distribution to broaden in general, but greater deformation of the larger drops at high shear rates causes the drop-size distribution to remain narrow. 相似文献
663.
R. L. Hudson 《Ukrainian Mathematical Journal》1997,49(3):514-522
The classical Hausdorff-Young inequality for the Fourier transformation is generalized to various quantum contexts involving
noncommutative L
p
-spaces based on translation-invariant traces.
University of Nottingham, Great Britain. Published in Ukrainskii Matematicheskii Zhurnal, Vol. 49, No. 3, pp. 465–471, March,
1997. 相似文献
664.
HYPOCRELLIN, FROM HYPOCRELLA BAMBUASE, IS PHOTOTOXIC TO HUMAN IMMUNODEFICIENCY VIRUS 总被引:9,自引:0,他引:9
J. B. Hudson J. Zhou J. Chen L. Harris L. Yip G. H. N. Towers 《Photochemistry and photobiology》1994,60(3):253-255
Abstract Hypocrellin, a photodynamic perylene quinonoid isolated from the Chinese medicinal fungus Hypocrella bambuase , was evaluated for antiviral activity against the human immunodeficiency virus (HIV-1). Hypocrellin was phototoxic to HIV-1, almost as good as the structurally similar plant pigment hypericin, and like hypericin its activity required visible light. In contrast peroxyhypocrellin had little or no effect on the virus. 相似文献
665.
Robert F. Hudson 《Angewandte Chemie (International ed. in English)》1973,12(1):36-56
The perturbation method of treating chemical reactions is discussed in a simple manner, by invoking the general hypothesis that the initial perturbation determines the course of a reaction. This approach is used to develop a general theory, as an alternative to the transition state theory. Such apparently diverse concepts as the symmetry rules for cyclic processes, and hard and soft acids and bases can be derived by this treatment, which is applied to radical reactions and aliphatic and aromatic substitution. 相似文献
666.
A. Alberti M. Benaglia M. A. Della Bona M. Guerra A. Hudson D. Macciantelli 《Research on Chemical Intermediates》1996,22(4):381-392
A number of radicals have been added to 1,3-bis(2,4,6-tri-tert-butylphenyl)diphospha-allene at low temperature in cyclopropane solution. Addition of thiyl and alkoxyl radicals occurs regiospecifically to one of the phosphorus atoms leading to new phosphavinyl radicals, isoelectronic with vinyl radicals, which have been characterised by means of EPR spectroscopy. The results of ab initio calculations are in agreement with the experimentally determined spectral parameters and suggest that these radicals are bent, with a PCP bond angle of ca. 150°. In contrast, silyl and germyl radicals appear to add to the carbon atom of the phosphaallene. 相似文献
667.
Collisionally activated spectra demonstrate that CH3CH2C?O+ rather than \documentclass{article}\pagestyle{empty}\begin{document}${\rm CH}_{\rm 2} = {\rm CHCH = }\mathop {\rm O}\limits^{\rm + } {\rm H}$\end{document} is formed in the metastable losses of hydrogen from [C3H6O]+˙ ions with the oxygen on the first carbon. This provides another example of formation of an acyl ion following ‘ketonization’ prior to metastable decomposition. 相似文献
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