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121.
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
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Two pathways for the protolysis of 1-(alkythio)-1-buten-3-ynes and the effect of cis-trans isomerism
A. N. Volkov A. N. Khuryakova R. N. Khudyakova V. V. Keiko B. A. Trofimov 《Russian Chemical Bulletin》1978,27(1):133-138
Conclusions We have used a spectrophotometric method to examine the kinetics of the hydrolysis of 1-(alkylthio)-1-buten-3-ynes to (alkylthio)butenones and acetoacetaldehyde; the rate of reaction depends markedly on the reactant configuration.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 153–159, January, 1978. 相似文献
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128.
N. A. Keiko L. G. Stepanova I. D. Kalikhman G. I. Kirillova M. G. Voronkov 《Chemistry of Heterocyclic Compounds》1975,11(5):526-528
It is shown that polarization of the endocyclic double bond in the electrophilic addition of alcohols and water to 2-formyl-2,5-dialkoxy-2,3-dihydro-γ-pyrans is directed toward the carbon atom in the 6 position. 相似文献
129.
Chen Y Pai A Somiya K Kawamura S Sato S Kokeyama K Ward RL Goda K Mikhailov EE 《Physical review letters》2006,97(15):151103
We propose a class of displacement- and laser-noise-free gravitational-wave-interferometer configurations, which does not sense nongeodesic mirror motion and laser noise, but provides a nonvanishing gravitational-wave signal. Our interferometers consist of four mirrors and two beam splitters, which form four Mach-Zehnder interferometers. By contrast to previous works, no composite mirrors with multiple reflective surfaces are required. Each mirror in our configuration is sensed redundantly, by at least two pairs of incident and reflected beams. Displacement- and laser-noise-free detection is achieved when output signals from these four interferometers are combined appropriately. Our 3-dimensional interferometer configuration has a low-frequency response proportional to f2, which is better than the f3 achievable by previous 2-dimensional configurations. 相似文献
130.
We investigated the effects of NaF, NaCl, NaBr, and NaI on the molecular organization of H2O by a calorimetric methodology developed by us earlier. We use the third derivative quantities of G pertaining to 1-propanol (1P) in ternary 1P-a salt-H2O as a probe to elucidate the effects of a salt on H2O. We found that NaF and NaCl worked as hydration centers. The hydration numbers were 19 +/- 2 for NaF and 7.5 +/- 0.6 for NaCl. Furthermore, the bulk H2O away from the hydration shell was found unaffected by the presence of Na+, F-, and Cl-. For NaBr and NaI, in addition to the hydration to Na+, Br- and I- acted like a hydrophilic moiety such as urea. Namely, they formed a hydrogen bond to the existing H2O network and retarded the fluctuation nature of H2O. These findings were discussed with respect to the Hofmeister ranking. We suggested that more chaotropic anions Br- and I- are characterized as hydrophiles, whereas kosmotropes, F- and Cl-, are hydration centers. 相似文献