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1.
2.
The zero field μSR-method has been used to study the magnetism in the disordered magnetic alloy Fe82−xNixCr18 near the three-critical, pointx=25. The dynamic and static local field distributions are analyzed. The difference between spin-glass states obtained either from the paramagnetic or after the double transition is discussed.  相似文献   
3.
A scheme for utilization of chloride solutions of complex composition with α-and β-activity of up to 35 and 28 kBq 1?1, respectively, is suggested.  相似文献   
4.
Conclusions Derivatives of trichloromethylmercury RHgCCl3 (R=n-C3H7, cyclo-C6H11, C6H5CH2, and C6H5), which are stable in the absence of air, were obtained in almost quantitative yield by the reaction of the corresponding mercury tert-butoxides RHgOC(CH3)3 with chloroform at room temperature.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2803–2805, December, 1968.  相似文献   
5.
5,6,7,8-Tetrafluoro-4-hydroxycoumarin reacted with benzylamine under mild conditions to give a stable salt, while its refluxing with aniline or benzylamine in xylene afforded 5,6,7,8-tetrafluoro-4-phenyl(benzyl)aminocoumarins. Reactions of 3-acetyl(acetimidoyl)-5,6,7,8-tetrafluoro-4-hydroxycoumarins with benzylamine followed different pathways, depending on the solvent. Condensation at the acyl substituent can be accompanied by replacement of the F atom in position 7. 3-Acetylcoumarin formed a salt, while 3-acetimidoylcoumarin yielded a 7-monosubstituted product. 3-Acetyl(acetimidoyl)-5,6,7,8-tetrafluoro-4-hydroxycoumarins reacted with aniline to give only 5,6,7,8-tetrafluoro-4-hydroxy-3-(N-phenylacetimidoyl)coumarin. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1170–1174, July, 2006.  相似文献   
6.
The giant mobility of the magnetic flux in FrFC and ZFC conditions have been studied in textured sample Bi2Sr2CaCu2O2- bySR. The comparison of results obtained in both cases showed that it is difficult to explain this phenomenon by only thermally activated flux creep and the melting of vortex lattice must be considered. The magnetic field dependence of the melting temperature was obtained for H<90mT. It is shown that the possibility of vortex motion does not affect the results of FC-measurements.  相似文献   
7.
An investigation of the hydration and amphiphilic properties of the piracetam and pramiracetam molecules has been conducted by theoretical conformational analysis and the Monte Carlo method; their localization and orientation at the water-lipophilic medium interface have been determined, which made it possible to explain the characteristics of the pharmacological action of the drugs.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 28, No. 4, pp. 355–358, July–August, 1992.  相似文献   
8.
The initial formation of organotin derivatives with Sn-S-N bonds in heterolytic reactions of hexamethylditin or trimethyltin sulfide withN-(chlorothio)phthalimide is suggested. Subsequent interaction of these compounds with sulfenyl chloride affordsN, N-thioorN, N-dithiobisphthalimide. Homolytic reaction of hexamethylditin withN, N-dithiobisphthalimide also occursvia an organotin intermediate, which, in the absence of a nucleophilic reagent, eliminates sulfur and converts intoN-trimethylstannylphthalimide.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2111–2114, December, 1993.  相似文献   
9.
Novosibirsk Institute for Bioorganic Chemistry, Academy of Sciences of the USSR, Military Section 61469. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 4, pp. 171–173, July–August, 1990.  相似文献   
10.
In the amine-catalyzed reactions of prenal with (Z)-5-methyl-2-(methoxycarbonyl)hexa-2,4-dienoic or (Z)-3-phenyl-2-(ethoxycarbonyl)prop-2-enoic acid chiral β-amino alcohols provide for higher enantiomeric purity of the resulting alkyl 4-methyl-6-(2-methylprop-1-enyl)-and 4-methyl-6-phenylcyclohexa-1,3-dienoates than that provided by related chiral amines without hydroxy group. The values ofee attained in nonpolar solvents are higher than those observed in the polar ones. Substituting stoichiometric amounts of a chiral 1-amino-3-methylbuta-1,3-diene for a combination of prenal with 0.1 equiv. of the corresponding chiral amine results in the products of much lower enantiomeric purity. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 84–92, January, 1998.  相似文献   
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