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61.
62.
Sorption and diffusion of Sr were examined using a typical Japanese bentonite. The experimental results showed that Sr sorption
on the bentonite had linear relationship between the equilibrium Sr concentration and Sr sorption amount, i.e., Henry’s type
of sorption, in wide initial Sr concentration from 1.1×10−9 to 1.1×10−4 mol L−1 at pH 10. The Sr sorption also indicated pH dependence in pH range between 2 and 12. Sorption modelling calculation indicated
that cation-exchange reactions contributed to Sr sorption in the pH range studied and a surface complexation reaction was
predominant above pH 8. Diffusion of Sr in loosely compacted bentonite bed was described by pore and surface diffusion and
surface complexation of Sr. Chemical-transport calculations reproduce the diffusion data at pH 5 using the cation-exchange
parameters obtained in the analysis of the batch sorption experiment. 相似文献
63.
Michinori Karikomi Mari Yamada Hirohiko Houjou Kazuhisa Hiratani Tadao Uyehara 《Tetrahedron letters》2005,46(35):5867-5869
Oxidative coupling reaction of both 3-hydroxychrysene and 2-hydroxybenzo[c]phenanthrene by using Cu(NO3)2-3H2O under atmospheric air is described. The former gave the aimed coupled biaryl derivative. However, the latter gave a further oxidized helical quinone derivative. The unique helical structure was characterized by X-ray and NMR analysis. 相似文献
64.
Novel stereospecific isomerization of 2-(1-bromoalkyl)-1-sulfonylaziridines into 2-(bromomethyl)-3-alkyl-1-sulfonylaziridines using magnesium bromide is described. The suitable choice of solvent led to good yields and diastereoselectivites. 相似文献
65.
66.
Miscibilities of methanol and ethanol with dodecylammonium chloride in the adsorbed film and micelle
N. Ikeda A. Tsukamoto C. Murakado M. Villeneuve T. Takiue M. Aratono K. Motomura 《Colloid and polymer science》1998,276(3):267-273
The surface tension of the aqueous solutions of methanol– dodecylammonium chloride (DAC) and ethanol–DAC mixtures has been measured as a function of the total molality of the mixture m^ and the mole fraction of DAC X^2 in the mixture at 298.15?K under atmospheric pressure. The compositions of the adsorbed film at 50, 40, and 30?mN?m-1, and that of the micelle at the critical micelle concentration (CMC) have been evaluated by applying the thermodynamic equations derived previously and shown in the form of phase diagrams of adsorption and micelle formation. It has been found that (i) methanol is hardly miscible in M28.8nthe adsorbed film and micelle, and (ii) ethanol molecules are very slightly incorporated into adsorbed film of DAC at high-surface tension and into the micelle, although hardly miscible in the adsorbed film at low-surface tension. By comparing the corresponding phase diagrams of ethanol-2- (octylsulfinyl)ethanol (OSE) mixture, furthermore, it has been shown that there exists a difference in the miscibility of ethanol between DAC and OSE. 相似文献
67.
Satoshi Fukui Osami Tsukamoto Kazuaki Negishi 《Physica C: Superconductivity and its Applications》1998,310(1-4):142-146
We investigated the AC loss characteristics of a low temperature NbTi AC wire by measuring the AC transport current losses in the external AC magnetic field whose components are the longitudinal and transverse ones. The measurement results showed that the AC losses were significantly dependent on the directions and magnitudes of the external longitudinal field component. The AC losses caused by the longitudinal and azimuthal field components were estimated by our previously derived model. The theoretical results well explained the dependence of the AC losses on the longitudinal field components. It was also shown that the AC losses can be substantially reduced by the proper choice of the twisting way. 相似文献
68.
Lignans from bark of the Olea plants. I 总被引:1,自引:0,他引:1
69.
70.