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131.
Peters AJ Chichak KS Cantrill SJ Stoddart JF 《Chemical communications (Cambridge, England)》2005,(27):3394-3396
Borohydride reduction of a Borromean Ring (BR) complex containing six zinc(II) ions and 12 imine bonds has resulted in its demetallation, producing a neutral BR compound and also its free macrocycle, following cleavage of at least one of the imine bonds in the ethanolic reaction mixture. 相似文献
132.
J. Burgess C.J.W. Fraser R.D. Peacock P. Taylor A. Majid J.M. Winfield 《Journal of fluorine chemistry》1973,3(1):55-61
Enthalpies of formation of the tungsten (VI) compounds WF5Cl, WF4Cl2, WF5(OMe), cis-WF4(OMe)2 and cis-WF2(OMe)4 are reported. Re-distribution and decomposition reactions in the chloride-fluoride and in the methoxide-fluoride series are discussed in the light of the thermochemical results. 相似文献
133.
W.B. Fraser 《Journal of sound and vibration》1980,72(2):151-157
A separable form of the equations of motion for a cylindrical anisotropic elastic waveguide of arbitrary cross-section is derived. From these the orthogonality relation for the modes of harmonic wave propagation in the waveguide is readily derived. 相似文献
134.
Data are presented on the dc conductivity, thermopower and optical absorption of glasses in the CuAs2Se3 system. The electronic properties of the alloys differ markedly from those of As2Se3, but variations in composition do not introduce significant changes in properties, until the atomic percent of copper is greater than 25. The results are interpreted in terms of small polaron transport. 相似文献
135.
136.
137.
Self-assembled multivalent pseudopolyrotaxanes, composed of lactoside-bearing cyclodextrin (CD) rings threaded on linear polyviologen polymers, have been introduced recently as flexible and dynamic neoglycoconjugates. In the course of this research, it was found that polyviologens are responsive to the Bradford assay, which is traditionally highly selective for proteins. The response of the pseudopolyrotaxanes to the Bradford assay was dependant on, and thus indicative of, the degree of threading of the CD rings onto the polyelectrolyte. The assay was then used to report on the threading and dethreading of native and lactoside-bearing alpha-CD rings onto and off of polyviologen chains, a phenomenon which demonstrates the utility of biochemical assays to address problems unique to supramolecular chemistry. 相似文献
138.
[reaction: see text] A new silica-supported zinc-copper matrix dramatically promotes conjugate additions of alkyl iodides to alkenenitriles in water. Acyclic and cyclic nitriles react with functionalized alkyl iodides, overcoming the previous difficulty of performing conjugate additions to disubstituted alkenenitriles with nonstabilized carbon nucleophiles. Conjugate additions with omega-chloroalkyl iodides generate cyclic nitriles primed for cyclization, collectively providing one of the few annulation methods for cyclic alkenenitriles. 相似文献
139.
[Structure: see text] The versatility of supramolecular chemistry has been exploited in constructing nanovalves based on mesoporous silica MCM-41 and the mutual recognition between secondary dialkylammonium ions and dibenzo[24]crown-8 (DB24C8). Naphthalene-containing dialkylammonium threads were tethered to the MCM-41, followed by loading with coumarin 460 and capping with DB24C8. Controlled release of coumarin 460 from the pores of MCM-41 was demonstrated using different bases. The rate of release of coumarin 460 from the nanovalves depends on the size of the base. 相似文献
140.
Vincent KA Cracknell JA Clark JR Ludwig M Lenz O Friedrich B Armstrong FA 《Chemical communications (Cambridge, England)》2006,(48):5033-5035
We demonstrate an extreme test of O(2) tolerance for a biological hydrogen-cycling catalyst: the generation of electricity from just 3% H(2) released into still, ambient air using an open fuel cell comprising an anode modified with the unusual hydrogenase from Ralstonia metallidurans CH34, that oxidizes trace H(2) in atmospheric O(2), connected via a film of electrolyte to a cathode modified with the fungal O(2) reductase, laccase. 相似文献