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1.
2.
For bounded normal operators in Krein spaces we give a necessary and sufficient condition for strong stability. The same result for unitary operators was obtained by M.G.Krein [1] (see also [2]). For selfadjoint operators we refer to the papers of P.Jonas, H.Langer [3] and H.Langer [4].  相似文献   
3.
On the basis of a comparison of the experimental dipole moments with the calculated values, as well as data from the UV, IR, and PMR spectra, it is shown that 3-acylindoles exist in the form of equilibrium mixtures of the planar S-cis and S-trans conformers with preponderance of the latter.DeceasedTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1647–1652, December, 1982.  相似文献   
4.
1.  Ethylbenzene in acetonitrile is slowly oxidized by atmospheric oxygen to acetophenone in the presence of a catalytic amount of CrO3.
2.  Ethylbenzene is oxidized to acetophenone by iodosobenzene in acetonitrile in the air in the presence of catalytic amounts of CrO3 and -picolinic acid.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1185–1188, May, 1989.  相似文献   
5.
6,7-Dimethylbenzimidazo[2,1-b]thiazolid-3-one was synthesized, and its reactions with aldehydes, isatin, nitroso compounds, and arene diazonium salts were studied. As a result, ylidene and imino derivatives and azo coupling products were obtained. According to the IR spectra, the azo coupling products have 6,7-dimethylbenzimidazo[2,1-b]thiazolidine-2,3-dione 2-arylhydrazone structures.See [1] for communication LVI.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 822–825, June, 1971.  相似文献   
6.
The borling temperatures of perfluoro-2,4,6,9,11,13-hexaoxy-n-tetradecane, perfluoro-2,4,6,8,11,13,15,17-octaoxy-n-octadecane, and perfluoro-2,4,6,8,11,13,15,17,19,21-decaoxy-n-docosane were determined by comparative ebulliometry over the saturated vapor pressure range 6.2–101.6 kPa. The heat capacity of perfluoro-2,4,6,8,11,13,15,17-octaoxy-n-octadecane was studied by adiabatic calorimetry over the temperature range 5.3–371.2 K. The densities of the substances at 296–338 K were measured in quartz pycnometers. The data obtained were used to calculate the normal boiling points, enthalpies of vaporization, critical parameters, and thermodynamic functions (entropy, enthalpy, and Gibbs energy) of the polyethers studied.  相似文献   
7.
>CrO3, (NBu4)2CrO4, (NBu4)2Cr2O7, and (NBu4)Cr4O13 catalyze the hydrogen peroxide oxidation of cyclohexane, ethylbenzene, and styrene in acetonitrile. The active species is apparently a Cr(VI) peroxo complex.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 210–211, January, 1990.  相似文献   
8.
1-Ethoxycarbonyl-3-phenyl- and 3-phenylpyrazino[1,2-a]benzimidazoles were synthesized by reaction of 2-ethoxalyl- and 2-diethoxymethyl-N-phenacylbenzimidazoles, obtained from the corresponding sodium derivatives of benzimidazole and phenacyl bromide, with ammonium acetate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1266–1267, September, 1976.  相似文献   
9.
Irradiation by light with >520 nm of solutions of cyclohexane, n-hexane, and ethylbenzene in CH2Cl2 in air in the presence of the complexes (Bu4N)2. Cr2O7, (Bu4N)2Cr3O10, or (Bu4N)2Cr4O13 results in formation (after GLC) of the corresponding alcohols and ketones. Under these conditions, styrene epoxide, benzaldehyde, and acetophenone are produced from styrene; alcohols are oxidized to carbonyl compounds; and triphenylphosphine forms triphenylphosphine oxide.For previous communication, see [1]. Preliminary reports have been published [2, 3].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2463–2468, November, 1991.  相似文献   
10.
The objective of the study is themass spectrometry analysis of the protein composition in blood plasma samples of large intestine cancer patients. Protein profiles of 58 blood plasma samples of large intestine cancer patients and healthy volunteers are analyzed using ultrahigh-resolution panoramic mass spectrometry. It is shown that the coincidence of identifications in the protein composition samples of intestine cancer patients and healthy men is 60–80%. Samples of intestines cancer patients contain proteins involved in the interaction with ribonucleic acid, proteins, and lowmolecular substrata.  相似文献   
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