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151.
Thiocarbonyl ylide was found to be generated by thermolysis of bromo(trimethylsilylmethylthio)methyltrimethylsilane and its 1,3-cyclo-addition provided a new method for synthesis of tetrahydrothiophenes. 相似文献
152.
Yusuke Sasaki Masahiko Imai Jun Tanaka Harumichi Shimizu 《Journal of polymer science. Part A, Polymer chemistry》1988,26(9):2465-2473
Polypropylene films were irradiated with 60Co γ-rays in divinylsulfone (DVS) or butadiene (BD) gases. The variations of the intrinsic viscosities of the samples irradiated in vacuum or in DVS with dose showed usual patterns but the variation of the latter was somewhat more rapid. The intrinsic viscosity of the sample irradiated in BD could not be measured due to the early appearance of gel. The gel fraction of the sample irradiated in DVS appeared at lower dose than that irradiated in vacuum, but the former did not increase as much as the latter. The gel fraction of the sample irradiated in BD increased remarkably. The concentrations of the two kinds of double bonds increased in the sample irradiated in BD but levelled off gradually with dose. ESR study showed that the polypropylene radical reacted with DVS to form anisotropic radicals. The mechanisms of the effects of both reagents on irradiation of polypropylene were discussed. 相似文献
153.
Imai K. und M. Matsumoto 《Colloid and polymer science》1962,184(1):69
Ohne Zusammenfassung 相似文献
154.
Imai T Hiraoka R Kovalenko A Hirata F 《Journal of the American Chemical Society》2005,127(44):15334-15335
Four water molecules confined in a small cavity of hen egg-white lysozyme were detected by means of the three-dimensional (3D) RISM theory, a statistical-mechanical theory of molecular solutions. This is the first theoretical realization of confined molecules in a protein without making nonsense tricks, such as placing the molecules in the space a priori. Possible impacts which the result may have on biochemistry and biophysics, including the molecular recognition, enzymatic reactions, etc., are discussed. 相似文献
155.
Yao K Imai Y Shi L Dong A Adachi Y Nishikubo K Abe E Tateyama H 《Journal of colloid and interface science》2005,285(1):259-266
A novel strategy for the synthesis of layered organosilica is demonstrated. The ionic interaction between the anionic group of a surfactant (sodium dodecyl sulfate) and the cationic organic group of an organosilane (3-aminopropyltrimethoxysilane, ATMS) under acidic conditions was utilized to create a layered organosilica at room temperature. The inorganic part of the organosilica layer was an Si-O hexagonal sheet, and organofunctional groups were alternately arranged on both sides of the sheet. The layered structure of the ATMS organosilica was retained after the removal of the surfactant with chloride anion. The properties of the layered ATMS organosilica were investigated. The layered ATMS-Cl organosilica is stable and possesses a definite layer structure in water or ethanol. Various kinds of anions can be intercalated in the interlayer space of the layered ATMS organosilicas and the layer was expanded dependent on the intercalated anions. The structure of the layered ATMS organosilica was well retained during the intercalation processes. 相似文献
156.
Onoda M Tokuyama H Uchiyama S Mawatari K Santa T Kaneko K Imai K Nakagomi K 《Chemical communications (Cambridge, England)》2005,(14):1848-1850
Strong fluorescence signals were observed after the reaction of novel reagents with hydroperoxides. 相似文献
157.
A hierarchically organized architecture in multiple scales was generated from potassium hydrogen phthalate crystals and poly(acrylic acid) based on our novel biomimetic approach with an exquisite association of polymers on crystallization. 相似文献
158.
159.
160.
Speckle patterns produced by coherent light from a GaA1As double-hetero-structure laser diode that has been transmitted through a multi-mode optical fiber are experimentally studied by analyzing the average contrast. It has been found that the speckle contrast observed in the far-field region is significantly lowered when the spectral width of a laser diode is as broad as a few tens of Angstroms. 相似文献