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1.
Reaction of benzothiazole-2-thione and benzothiazole-2-one with acetylene in the presence of potassium hydroxide or cadmium acetate gives 2-vinylthiobenzothiazole and 3-vinylbenzothiazol-2-one, respectively. Benzothiazole-2-thione is partially convened to benzothiazol-2-one by the action of Cd(OAc)2. Under vinylation conditions the latter also forms 2-vinylthioaniline.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 270–271, February, 1991. 相似文献
2.
L. I. Svyatkina N. D. Abramova L. L. Dmitrieva B. V. Trzhtsinskaya G. G. Skvortsova 《Chemistry of Heterocyclic Compounds》1982,18(11):1190-1193
The kinetics of the acidic hydrolysis of seven vinyl derivatives of benzimidazole-2-thione and benzoxazol-2-one and -2-thione were studied by means of polarography. The rate constants and energies of activation of the reaction were determined. The hydrolytic stabilities of the compounds depend on the nature of the heteroring and the site to which the vinyl group is attached.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1532–1535, November, 1982. 相似文献
3.
A. A. Dulov L. A. Abramova E. M. Stasenko V. N. Efremov G. M. Tesakova E. Z. Golosman V. I. Yakerson 《Russian Chemical Bulletin》1994,43(9):1471-1474
The surface phase composition of alumocalcium cement-supported CuO and CuO-NiO catalysts prepared by chemical mixing has been studied using the method of thermo-vacuum curves of electric conductivity. The deactivation of these catalysts due to overheating to 800 °C under conditions of hydrogenation of oxygen is rationalized by the partial extraction of CuO (and NiO) from the stabilizing structure of the support solid solutions and by sintering of the extracted oxides and the reduced metallic phase. Complete regeneration of the CuO-NiO-talum catalysts can be achieved if a considerable amount (20%) of copper hydroxocarbonate is added.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1559–1562, September, 1994. 相似文献
4.
E. A. Chernyshev T. L. Krasnova E. S. Abramova E. A. Abronin A. B. Petrunin A. P. Sergeev 《Russian Chemical Bulletin》1997,46(9):1582-1585
Pyrolysis of trichlorosilane (TCS) and copyrolysis of TCS with 1,3-butadiene were studied. The enthalpies and activation energies
for the reactions of the products of TCS pyrolysis were found by quantum-chemical calculations. A direct study of the pyrolysis
of TCS by mass spectrometry was carried out. Based on the thermochemical parameters found by quantum-chemical calculations
and on the results of GLC and mass spectrometry concerning the composition of the pyrolysis products, it was concluded that
the pyrolysis of TCS follows a scheme that includes formation of radicals and silylenes.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1659–1662, September, 1997. 相似文献
5.
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7.
V. V. Natarov L. N. Volovel'skii N. I. Pilipenko T. V. Zvyagintseva E. A. Bodrykh L. I. Simonova L. P. Abramova 《Chemistry of Natural Compounds》1990,26(1):70-71
A comparative study has been made of the radioprotector activity of cystamine and the synthesized cobalt and copper salts of N-succinylmethionine. Activity falls in the sequence cystamine-copper salt-cobalt salt.Khar'kov Scientific-Research Institute of Endocrinology and Hormone Chemistry. Khar'kov Medical Institute. Khar'kov Scientific-Research Institute of Medical Radiology. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 86–88, January–February, 1990. 相似文献
8.
Abramova N Borisov Y Bratov A Gavrilenko P Domínguez C Spiridonov V Suglobova E 《Talanta》2000,52(3):533-538
Application of a potassium ion sensor based on an ion sensitive field effect transistor (ISFET) for ion control of a dialysis solution in an artificial kidney and in blood plasma of patients treated by hemodialysis is presented. Sensors and their long-term stability were characterised in constant contact with test solutions. Test results are compared to those obtained with conventional ion-selective electrodes and commercial blood ion analyser. Tested ISFET sensors showed high reliability in potassium ion measurements in the physiologically significant concentration range which, along with low cost of their production, makes them promising for cited application. 相似文献
9.
H. N. Altshuler L. P. Abramova N. V. Malyshenko G. Yu. Shkurenko E. V. Ostapova 《Russian Chemical Bulletin》2005,54(8):1978-1981
The ion-exchange equilibrium in network polymers obtained from cis-2,8,14,20-tetraphenyl-4,6,10,12,16,18,22,24-octahydroxycalix[4]arene by template synthesis on cations Na+, K+, and Ba2+ as matrices was studied. The selectivity coefficients of ion exchanges Ba2+-H+, Na+-H+, K+-H+, Na+-K+, and Na+-NH4
+ were determined. The template synthesis enhanced the affinity of the polymers to matrix-forming cations by 6–8 kJ mol−1.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1919–1922, August, 2005. 相似文献
10.
V. N. Elokhina A. S. Nakhmanovich E. V. Abramova L. I. Larina 《Russian Journal of Organic Chemistry》2006,42(10):1426-1428
1,1,4,4-Tetramethylsemicarbazide readily undergoes alkylation with prop-2-ynyl bromide and allyl bromide at the tertiary nitrogen atom of the hydrazine fragment to give 1-(prop-2-yn-1-yl)-and 1-(prop-2-en-1-yl)-1,1-dimethyl-2-(dimethylaminocarbonyl)hydrazinium bromides, respectively. A new procedure was proposed for the synthesis of 6-bromomethylidene-2-dimethylamino-4,4-dimethyl-5,6-dihydro-4H-1,3,4-oxadiazin-4-ium bromide by reaction of 1,1,4,4-tetramethylsemicarbazide with 1,3-dibromoprop-1-yne in acetonitrile. 相似文献