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321.
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Under visible light irradiation (lambda = 420-500 nm), a tantalum oxynitride, TaON, functions as a stable and very efficient photocatalyst for oxidation of water into O2 with a sacrificial electron acceptor (Ag+).  相似文献   
323.
We present a novel strategy for connection of phenotype and genotype in vitro that can be used for the selection of functional proteins even at room temperature. The strategy involves generation of a stable complex between a ribosome, an mRNA, and its translated protein, without removal of the termination codon, as a result of the action of the ricin A chain during translation. We demonstrate the potential selection capacity of this novel strategy by isolating such complexes that contain newly synthesized streptavidin and glutathione-S-transferase (GST) using appropriate ligands. The technique requires no transfection, no chemical synthesis, no ligation, and no removal of the termination codon. Thus our novel "Ribosome-Inactivation Display System (RIDS)" should provide, without loss of the pool population, a reliable, simple, and robust selection system for in vitro evolution of the properties of proteins in a predictable direction by a combination of randomization and appropriate selection strategies.  相似文献   
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Conformational isomerizations of radical-ions are studied both experimentally and theoretically- The representative systems of stilbenes, polyenes, and non-planar alicyclic compounds will be reviewed first. Then, the result of the study on the radical-cations of 1,4-dithiacyclohexane and ethane-1,4-dithiol will be presented. It is found that the former cation suffers a change from a chair fore to a boat form and the latter from an anti- or a gauche-form to a cis form even in a rigid matrix. The conformational changes are manifested by drastic changes in the electronic absorption and ESR spectra- The strong “through-space” interaction between the lone pair orbitals of the sulfur atoms is responsible for the conformational changes. Ab initio óó'O calculations lend support to the analysis of the experimental results.  相似文献   
326.
Nucleic acids possess several metal cation recognition sites, including phosphates, nucleobases and possibly riboses. This article focuses on the detection of nucleobase-metal interactions by NMR spectroscopy.  相似文献   
327.
Isothermal vapor-liquid equilibrium data for the ethane—carbon dioxide system at high pressures were obtained at 10, 15, 18, 20, and 25°C.The gas-liquid critical data (pressure—temperature—composition) for the system were also measured at several temperatures, and the azeotropic points were obtained at 10, 15, and 18°C. This system exhibits two critical points and one azeotropic point in the temperature range from 17.5°C to 18.5°C.  相似文献   
328.
Newly designed and prepared vanadium complexes bearing anionic pyrrole‐based PNP‐type pincer and aryloxy ligands were found to work as effective catalysts for the direct conversion of molecular dinitrogen into ammonia and hydrazine under mild reaction conditions. This is the first successful example of vanadium‐catalyzed dinitrogen reduction under mild reaction conditions.  相似文献   
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The graft polymerization of acrolein (AL) on poly-4(5)-vinylimidazole or the copolymers of 4(5)-vinylimidazole(VIm) and acrylamide of varying composition were carried out kinetically in an ethanol–water mixture at 0°C. The graft polymerization rate Rp increased with an increasing concentration of water in the solvent. On the other hand, the Rp of the copolymer which incorporated 50 mol % VIm showed the highest value. These results were discussed by assuming interaction between amide and imidazole groups in copolymer.  相似文献   
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