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31.
A new method for heat exchange between dispersed flows and a unit for continuous selective heating, comprising a heater and a mass-exchange apparatus, was proposed. A mathematical model of the unit was developed for the cases of direct-flow and counterflow heaters. Analytical solutions to the model equations were obtained. The parameters affecting the result of continuous selective heating of the dispersion medium in the unit were determined. 相似文献
32.
E. L. Gaidarova K. Rosher A. É. Aliev G. V. Grishina 《Chemistry of Heterocyclic Compounds》1992,28(10):1175-1178
Enantiomericalfy pure (–)-(10S)-6,10-dimethyl-6-am-1,9-octahydroquinoline, which has been obtained from optically pure (3S)-1,3-dimethyl-3-(2-cyanoethyl)piperid-4-one, is a chiral intermediate for the preparation of novel biologically active compounds and an analog of piperidine and decahydroquinoline alkaloids. The chiroptical properties of the synthesized 6-azaoctahydroquinoline are examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1379–1383, October, 1992. 相似文献
33.
R. G. Aflyatunova N. A. Aliev Ch. Sh. Kadyrov M. R. Yagudaev 《Chemistry of Natural Compounds》1984,19(4):478-482
The reactions of benzoxazolinone and benzoxazolinethione with alkyl -chlorovinyl ketones have been studied. The reaction products are N-(-acylvinyl)benzoxazolinones and N-(-acylvinyl)benzoxazolinethiones. The reaction of alkali-metal salts of benzoxazolinone with alkyl -chlorovinyl ketones leads to the opening of the oxazolinone ring. The structures of the compounds synthesized have been studied by IR, mass, and PMR spectroscopy.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 507–511, July–August, 1983. 相似文献
34.
A. é. Aliev V. V. Kuznetsov L. A. Gaivoronskaya N. S. Prostakov 《Chemistry of Heterocyclic Compounds》1989,25(10):1176-1179
The product of condensing 1,2,5-trimethylpiperidin-4-one with aniline has been investigated by NMR spectroscopy. Three isomers of N-(1,2,5-trimethyl-4-piperidylidene)aniline have been identified differing in the configuration of the methyl groups at C2 and C5 of the piperidine ring and the Z,E isomerism about the C=N bond. Traces of the enamine tautomeric form of the imine were also detected.
,
, and
spin-spin couplings were used to determine the structural configuration of the isomers.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1405–1408, October, 1989. 相似文献
35.
A method has been developed for obtaining 3-vinylbenzoxazolinones and 3-vinylbenzoxazolinethione. It has been shown that it is also possible to obtain 3-methylbenzoxazolinethione by this method in good yield (76%). 相似文献
36.
Allakhverdiev SI Feyziev YM Ahmed A Hayashi H Aliev JA Klimov VV Murata N Carpentier R 《Journal of photochemistry and photobiology. B, Biology》1996,34(2-3):149-157
The protective action of co-solutes, such as sucrose and glycinebetaine, against the thermal inactivation of photosystem II function was studied in untreated and Mn-depleted photosystem II preparations. It was shown that, in addition to the reactions that depend on the oxygen evolving activity of the photosystem, those that implicate more intimately the reaction center itself are protected by high concentrations of osmolytes. However, the temperature required to inhibit oxygen evolution totally in the presence of osmolytes is lower than that required to eliminate reactions, such as P680 (primary electron donor in photosystem II) photo-oxidation and pheophytin photo reduetion, which only involve charge separation and primary electron transport processes. The energy storage measured from the thermal dissipation yield during photoacoustic experiments and the yield of variable fluorescence are also protected to a significant degree (up to 30%) at temperatures at which oxygen evolution is totally inhibited. It is suggested that a cyclic electron transport reaction around photosystem II may be preserved under these conditions and may be responsible for the energy storage measured at relatively high temperatures. This interpretation is also supported by thermoluminescence data involving the recombination between reduced electron acceptors and oxidized electron donors at - 30 and - 55 °C. The data also imply that a high concentration of osmolyte allows the stabilization of the photosystem core complex together with the oxygen-evolving complex. The stabilization effect is understood in terms of the minimization of protein-water interactions as proposed by the theory of Arakawa and Timasheff (Biophys. J., 47 (1985) 411--414). 相似文献
37.
38.
Z. G. Aliev L. O. Atovmyan A. M. Sipyagin V. G. Kartsev O. V. Dobrokhotova 《Chemistry of Heterocyclic Compounds》1987,23(4):390-395
A one-step synthesis of azetidin-3-ones by intramolecular cyclization of 1-diazo-3-arenesulfamoylalkan-2-ones was developed. The yield of cyclic product increases to 70% in the presence of an alkyl or benzyl substituent in the hydrocarbon chain of the diazoketone. The structure of N-tosyl-2-ethylazetidin-3-one was studied by x-ray diffraction analysis and it was shown that the four-membered ring has 15 inflection.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 468–473, April, 1987. 相似文献
39.
Z. G. Aliev A. M. Sipyagin V. G. Kartsev L. O. Atovmyan 《Russian Chemical Bulletin》1986,35(1):120-124
Conclusions Under the conditions of the acidic cyclization reaction of homologous 3- and 4-[(4-chlorophenyl)sulfamoyl]-1-diazoalkan-2-ones, the formation of the five-membered heterocycle, a pyrrolidin-3-one derivative, is more convenient than the formation of the four-membered heterocycle- an azetidin-3-one derivative. These results are in agreement with the differences in conformations of diazoalkane molecules in the crystalline state.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 134–138, January, 1986. 相似文献
40.