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181.
Isao Saito Shigeru Muramatsu Hiroshi Sugiyama Akihiro Yamamoto Teruo Matsuura 《Tetrahedron letters》1985,26(48):5891-5894
Photochemical hydrogen-deuterium exchange reaction of biologically important indoles is reported. The regioselectivity of the photodeuteration was found to be controlled by the ammonium group of the side chain. 相似文献
182.
The early stage of hydrolysis and polycondensation of tetraalkoxysilanes (TAOS) in the closed TAOS-C2H5OH-H2O-HCl system at 40°C was studied by the trimethylsilylation technique combined with the gas-liquid and gel permeation chromatographies. Tetramethoxy, tetraethoxy, tetra (n-propoxy) and tetra (n-butoxy) silanes were used as TAOS. The tendencies of variation with time in the distribution and molecular weight of silicate species in the solutions were almost the same in all the TAOS solutions, suggesting that the differences in the alkyl group of the TAOS had little effect on the hydrolysis and polycondensation. 相似文献
183.
184.
Eiichi Takahashi Isao Matsushima Yuji Matsumoto Isao Okuda Yoshiro Owadano 《Optics Communications》1998,150(1-6):56-60
Initial movement of laser irradiated foil targets has been measured by face-on interferometry with two-dimensional resolution. This interferometric method provides direct and precise information about the initial movement of the rear surface of the target compared with conventional diagnostics. Target movement of 20–500 nm from the original position has been observed. 相似文献
185.
186.
Takeshi Yamanobe Isao Ando Hazime Saitô Ryoko Tabeta Akira Shoji Takuo Ozaki 《Chemical physics》1985,99(2):259-264
An attempt was made to calculate 13C NMR chemical shifts of poly(β-benzyl L-aspartate) having the right-handed α-helix (αR-helix) and left-handed α-helix (αL-helix) forms by a tight-binding MO sum-over-states theory within the extended Hückel framework, in order to examine whether or not the conformation-dependent 13C chemical shifts previously determined by the cross polarization-magic angle spinning technique are reproduced by a change of electronic structure of the polymer. It is found that the relative displacements of the observed Cα, Cβ and carbonyl 13C chemical shifts between the αR- and αL-helices are reproduced qualitatively by the calculation. 相似文献
187.
The growth of cells on polymers prepared by the radiation polymerization of monomethacrylate and dimethacrylate was investigated. Cell growth was affected greatly by such properties of the polymers as water content, wettability, and porosity. Growth was promoted remarkably by rinsing the polymers with warm water at 60-70 degrees C and by irradiation of polymers with an electron beam. Cell growth decreased with increasing oxyethylene length (n) in the polymerized dimethacrylate of same series, CH2C(CH3)CO(OCH2CH2)nOCOC(CH3)CH2. A decrease in the hydrophilicity of the polymer increased cell growth rate. Formation of pore structures in the polymer films also increased the cell growth. 相似文献
188.
Nickel(II) complexes of N3O2 donor macrocycles incorporating 17- to 19-membered macrocyclic rings have been prepared. Physical measurements ind 相似文献
189.
190.
On the basis of chemical and physicochemical evidence, the structure of holothurin A, a biologically active major obligoglycoside o lanostane-type triterpene holothurigenol (), has been elucidated to be . 相似文献