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101.
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Akon Higuchi Masatomo Abe Jiro Komiyama Toshiro Iijima 《Journal of membrane science》1984,21(2):113-121
Permeabilities and diffusion coefficients of various gases, Ar, N2, O2, CO2, CH4, C2H4, C3H8 and C4H10, were measured for Water-swollen gel cellophane membranes. No dependence of permeabilities on gas pressure below 1 atm was found. It was observed that the permeability coefficients were not related linearly to the coefficients in bulk water. For the two states of water in the membrane, an analytical method is presented to estimate the diffusion coefficients and the solubilities in free water and non-freezing water. It was found that the diffusion coefficients in non-freezing water were lower than those in free water, and the solubilities in non-freezing water were higher than in free water for all gases studied except CO2 and C2H4, which gave reverse results. 相似文献
104.
2-(2-Dithianyl)benzhydrols ( a-c) undergo facile cycloaddition reaction with maleic anhydride under thermal conditions to give 1-phenyl-naphthalenes ( a-c) in one step. The naphthalenes ( a-c) have been converted into the naphthalene lignan lactones, ( a-c) and ( a-c). 相似文献
105.
The Ag electrode surface of a solid electrolyte in its working state has been studied by X-ray photoelectron spectroscopy. The nature of the AgO system on the electrode is dependent on the temperature. There are three types of AgO systems at 400°C. Type 1 with an O is binding energy of 532.6 eV only appeared at 325°C. However, when the temperature was raised to 400°C, types II and III (with BEs 531.1 and 529.2 eV) appeared. These O is signals are discussed in detail. 相似文献
106.
Annals of the Institute of Statistical Mathematics - In Part I the Khintchine’s uniqueness theorem for the class convergence of probability distributions is proved in a natural way by making... 相似文献
107.
Palladium-catalyzed carbonylation of 3,5-dimethoxybenzyl chloride (13) with benzyl 7-hydroxyoctanoate (12) afforded benzyl 7-(3,5-dimethoxyphenylacetoxy)octanoate (6) in 70% yield, which is the precursor of Curvularin (4). The ester (12) was easily prepared from the butadiene telomer obtained by the palladium-catalyzed reaction of butadiene with acetic acid. 相似文献
108.
Diethyl 9-octadecene-1,18-dioate was obtained in 87% yield based on 50% theoretical conversion by the olefin metathesis reaction catalyzed by WOCl4-Cp2TiMe2. The Dieckmann condensation of this diester using potassium hydride afforded 2-ethoxycarbonylcyclo-9-heptadecenone, which was converted by hydrolysis and decarboxylation to cyclo-9-heptadecenone (civetone) as a mixture of cis and trans isomers (1.3 : 1) in 54% yield. Also 9-octadecen-18-olide was obtained in 17.9% by the metathesis of oleyl oleate. 相似文献
109.
Yuji Yaegashi Seiji Adachi Takahiro Wada Satoshi Takano H. Yamauchi 《Physica C: Superconductivity and its Applications》1992,190(4):433-436
Yb(Ba1−xSrx)2Cu4O8 (0.1x0.3) superconductors of the YBa2Cu4O8(“124”) structure were successfully synthesized using an O2-hot-isostaticc-pressing (HIP) technique. The samples were characterized with respect to the crystal structure and superconducting properties. The lattice parameters of the samples decreased as the substitution of Sr for Ba proceeded. The superconducting transition temperatures of all the Yb-“124” samples were more or less the same, being around 80 K. 相似文献
110.
The signal quality of a fiber-optic distributed temperature sensor based on optical time domain reflectometry (OTDR) is improved using a pre-filtering technique in the iterative deconvolution method. Investigation of the performance is proposed using iteration conditions in which recovery rate of the signal-component is equal to that of the unfiltering technique. The recovered signal in the pre-filtering technique gives a good signal-to-noise ratio (SNR), 3 times of the unfiltered signal. Consequently, improvements in the OTDR signal with SNR of from 10 to 100 are obtained under the iterations for both distance and temperature resolutions. 相似文献