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1.
2.
V. A. Vinokurov Yu. N. Polivin M. A. Silin E. A. Ageev M. A. Zatikyan R. A. Karakhanov 《Russian Chemical Bulletin》1989,38(9):1984-1984
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2154–2155, September, 1989. 相似文献
3.
É. A. Karakhanov S. Kh. Sharipova M. I. Rozhkova E. A. Viktorova 《Chemistry of Heterocyclic Compounds》1978,14(1):15-16
It is shown that the principal pathway in the reaction of benzofuran with a solution of lithium in hexametapol is opening of the furan ring of benzofuran to give a dilithium derivative. Mono- and dialkylation products are formed when the reaction mixture is treated with alkylating agents. It was established by the use of alkylating agents with different degrees of hardness that the oxygen atom is a softer polarizable center than the sp-hybridized carbanion center.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 22–23, January, 1978. 相似文献
4.
Yu. N. Polivin R. A. Karakhanov T. S. Sheveleva E. A. Ageev A. S. Remizov 《Russian Chemical Bulletin》1991,40(12):2518-2520
The reaction of 2-ethyl-3-tetrahydrofuryl thiocyanate (I) and triphenylacetonitrile (VIII) with methylmagnesium iodide in ether was studied using GC/MS, PMR and13C NMR spectroscopy. The reaction of (I) with CH3MgI gives the product of the homolysis of the C-S bond, namely, bis(2-ethyl-3-tetrahydrofuryl) disulfide (II), in 81% yield. This reaction is assumed to be general in nature since triphenylacetonitrile (VIII) is also homolytically cleaved by the action of CH3MgI to give triphenylmethane.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2886–2888, December, 1991. 相似文献
5.
V. A. Slavinskaya R. A. Karakhanov L. Yu. Brezhnev I. I. Geiman L. F. Bulenkova A. K. Strautinya 《Chemistry of Heterocyclic Compounds》1982,18(10):997-1008
Various methods for the preparation of 2,3-dihydrofuran, 2,5-dihydrofuran, 2-methylenetetrahydrofuran, and their alkyl and aryl derivatives are examined. The most promising method for the preparation of 2,3-dihydrofuran is the conversion of 1,4-butanediol on cobalt catalysts. 2,5-Dihydrofuran is obtained by dehydration of 2-butene-1,4-diol on Al2O3, cobalt-containing and other catalysts, while 2-methylenetetrahydrofuran is obtained by dehydrohalogenation of tetrahydrofurfuryl halides. The various methods for the isomerization of 2,5-dihydrofuran to 2,3-dihydrofuran are discussed. Examples of the application of dihydrofurans in organic synthesis are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1299–1311, October, 1982. 相似文献
6.
L. S. Povarov V. I. Grigos R. A. Karakhanov B. M. Mikhailov 《Russian Chemical Bulletin》1965,14(2):344-345
Summary In the presence of BF3 etherate, vinyl ethyl ether and 2-methyl-4,5-dihydrofuran react with halogen-containing Schiff bases to give the corresponding quinoline derivatives.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 365–367, February, 1965 相似文献
7.
V. I. Kelarev V. N. Koshelev N. V. Belov O. V. Malova R. A. Karakhanov 《Chemistry of Heterocyclic Compounds》1994,30(2):218-221
6-Substituted 2,4-bis(trichloromethyl)-sym-triazet:es containing the 2,6-di-tert-butylphenol group are synthesized by simultaneous cyclotrimerization of trichloroacetonitrile with the nitrile or thiocyanate derivative of the sterically hindered phenol in the presence of gaseous HCl. Significant amounts of 2,4,6-tris(trichloromethyl)-sym-triazene are formed as a byproduct.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 240–243, February, 1994. Original article submitted January 19, 1994. 相似文献
8.
Kelarev V. I. Remizov A. S. Karakhanov R. A. Polivin Yu. N. Oietaio D. 《Chemistry of Heterocyclic Compounds》1992,28(10):1189-1193
Condensation of N-(4-hydroxy-3,5-di-tert-butylphenyl)biguanide with esters in the presence of catalytic amounts of sodium ethylate gives 2-amino-4-(4-hydroxy-3,5-di-tert-butylanilino)-6-substituted sym-triazines. When the trichloroacetate ester is used the main product is 2-amino-4-(4-hydroxy-3,5-di-tert-butylanilino)-6-oxo-1(5)H-sym-triazine.For communication 9 see [1]Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1395–1399, October, 1992. 相似文献
9.
Summary Over platinized charcoal at 300° 1-(2-furyl)-3-alkanols, as a result of the hydrogenolysis of the furan ring, and 1-(tetrahydro-2-furyl)-3-alkanols, as a result of the isomerization of the tetrahydrofuran ring, give-diketones in yields of 35–50%. 相似文献
10.
S. S. Shukurov M. A. Kukaniev I. M. Nasyrov K. S. Zakharo R. A. Karakhanov 《Russian Chemical Bulletin》1993,42(11):1874-1878
Reactions of 2-bromo-7-methyl-5-oxo-5H-1,3,4-thiadiazolo[3,2-a]pyrimidine with sodium derivatives of pentane-2,4-dione, malonodinitrile, Meldrum acid, acetoacetic, cyanoacetic and malonic esters have been shown to give the respective substituted derivatives. Azinyl-ylidene tautomerism has been found to be characteristic of these compounds, the latter existing mainly in the ylidene form. The acid hydrolysis of pentane-2, 5-dione and cyanoacetic and malonic esters derivatives has been investigated.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1957–1961, November, 1993 相似文献