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111.
112.
We construct four new infinite families of ovoids in the 8-dimensional orthogonal geometry O inf8 sup+ . We determine the automorphism groups of these ovoids and we show that the two sporadic ovoids recently found by Cooperstein [2] and Shult [11] are members of our families.  相似文献   
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114.
Capsaicin has elicited great interest for many centuries due to its noticeable culinary and medical properties. The discovery of its receptor, TRPV1, sparked an explosion of interest in TRPV1 and the development of TRPV1 agonists and antagonists. This tutorial review provides an introduction to the history of both capsaicin and TRPV1. Two TRPV1 antagonists that are undergoing clinical trials are highlighted, as are some light-activated molecular tools that are enabling the intracellular study of this protein. This article will be of interest to chemists and biologists with an interest in TRPV1, cell signalling, or medicinal and biological chemistry.  相似文献   
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A modified method is reported for the conversion of unsaturated sulfonamides into their cyclic saturated counterparts. This method utilises a single palladium catalyst for an intramolecular Heck reaction and subsequent transfer hydrogenation, which is achieved in one-pot following the addition of ammonium formate. Accordingly, a range of fourteen structural variations are reported and under optimal conditions the adducts were generated in typically good to excellent yields. Notably, discrimination of differentially substituted dienes can be accomplished in the case of compounds 28 and 29 and the process was only observed to fail with the more sterically hindered precursor 32.  相似文献   
117.
A two-dimensional cross-sectional poly-lattice kinetic Monte Carlo (2DCSP-KMC) model has been developed for simulation of the electrodeposition of polycrystalline copper on a copper and gold substrate. The mis-orientation and higher energetic state of grain boundaries are taken into account by introducing a ‘strange’ coordination number and a correction coefficient while determining the diffusion rate. The evolution of the microstructure, the average grain size, the variance of grain size and the distribution of grain-boundary mis-orientation of the deposit are also considered in simulations. The model has proven capable of capturing some key aspects of nucleation and growth mechanism including the nucleation type (e.g. homogeneous or heterogeneous), texture development, the growth of grains and higher energetic state of grain boundaries. The simulated microstructure qualitatively agrees with our experimental observation on the copper deposition on gold.  相似文献   
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119.
Reductive substitution, the process whereby a hydrocarbon ligand, usually a cyclopentadienyl group, in a transition metal complex is replaced by another unsaturated hydrocarbon with concomitant metal reduction has been utilized to prepare novel complexes of Cr°, CrI, MnI, CoI and Ni°. Similarly, ligand substitution, defined more generally as replacement of ligand(s) of a metal complex by an unsaturated hydrocarbon but with no change in the oxidation state of the metal, has resulted in the synthesis of a series of tetraphenylborate and substituted tetraphenylborate complexes of FeII, MoI, CrI, WI, and CoI. These procedures and the complexes derived therefrom are considered models for polymers incorporating a variety of novel features.  相似文献   
120.
A simple aqueous method for the conversion of alkyl and aryl azides into the corresponding amines using trisodium thiophosphate is presented. Thiophosphate is converted into phosphate during these formal reduction processes.  相似文献   
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