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91.
A new method of mixing sample and reagent due to the difference in their electrophoretic mobilities is introduced. Unlike electrophoretically-mediated microanalysis, sample and reagent are injected from the opposite ends of a capillary tube. This method is compared with electrophoretically-mediated microanalysis. Experiments are performed showing the possibilities of this new method. 相似文献
92.
V. A. Popov 《Journal of Elasticity》1993,30(2):107-121
An asympototic method developed by V.V. Kucherenko and the author is applied to the problem of free vibrations of a thin plate strip in a state of a plane strain. The first few terms of an asymptotic expansion of the natural frequencies are calculated. The results are compared with those obtained by using the classical and refined theories. 相似文献
93.
94.
Alexander I. Titkov Alexey N. Salanov Segrey V. Koscheev Andrey I. Boronin 《Reaction Kinetics and Catalysis Letters》2005,86(2):371-379
Summary The interaction of O2with Pd(110) has been studied by TDS and XPS at T = 400 K and at pressures PO2 from 2.6x10-6to 10 Pa. At low exposures in O2(e£1-5 L), an adsorption layer withqof ca.0.5 and with the O1s peak at BE = 529.3 eV has been found to form on the surface. Whenegrows from 5 to 108L, the position and intensity of the oxygen O1s peak remain practically constant. At the same time, as much as 5 mL of oxygen
is absorbed according to the TDS data. The results obtained by TDS and XPS indicate that oxygen penetrates deep into the subsurface
layers of palladium (315-20 ?) and is distributed in its bulk in a low concentration. 相似文献
95.
Valentine G Nenajdenko Georgy N Varseev Alexey V Shastin 《Journal of fluorine chemistry》2003,124(1):115-118
A novel catalytic approach to (2,2-difluorovinyl)benzenes has been developed. It was found that hydrazones of aromatic aldehydes generated in situ could be converted to the corresponding (2,2-difluorovinyl)benzenes by catalytic olefination reaction (COR) with dibromodifluoromethane in the presence of CuCl. 相似文献
96.
It has been shown that under conditions of phase-transfer catalysis under UV-irradiation perfluoroalkyl iodides react with aliphatic and aromatic thiols in the water-organic solvent media to form alkyl or aryl perfluoroalkyl sulfides in 60–80% yield. 相似文献
97.
V. A. Kiyashko A. K. Popov V. P. Timofeev N. P. Makarov V. Sh. Epstein 《Applied physics. B, Lasers and optics》1985,36(1):53-54
Generation of the second- and fourth-order harmonics of laser radiation is reported in Mg vapor at the forbidden 3s
21
S
o–4s
1
S
o transition. The conversion efficiency for the second-order harmonics has been measured to be 10–2% and for the fourth one 10–8%. 相似文献
98.
99.
The triplet-triplet absorption spectra of a number of aromatic molecules were shown to be broadened in low temperature matrices formed by aromatic solvents (toluene, 4-isopropylbiphenyl) as compared with those in aliphatic solvents (ethanol, methylcyclohexane, triethylamine). The effect is exponentially dependent on the energy of the upper triplet state of the solute molecule. The phenomenon is discussed in terms of a strong exchange-resonance interaction between the triplet states of solute and solvent. 相似文献
100.