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11.
V. L. Rusinonv A. Yu. Petrov G. G. Aleksandrov O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》1994,30(1):47-51
Stable anionic -adducts of azolo-ring condensed 1, 2, 4-traizines with water were synthesized, and their x-ray structural analysis was carried out.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 52–57, January, 1994. 相似文献
12.
I. E. Filatov G. L. Rusinov O. N. Chupakhin X. Solans M. Font-Bardia M. Font-Altaba 《Russian Chemical Bulletin》1994,43(7):1214-1219
The reaction of 2-chloro-3,5-dinitropyridine with two equivalents of KN3 in the presence of ROH results in stable Meisenheimer-type -adducts of 4,6-dinitrotetra-zolo[1,5-a]pyridine with RO– anions (R = H, Alk, Ph). The mechanism of -complex formation was suggested. The structure of the -adduct with R = Me was established by IR and NMR spectroscopy and by X-ray diffraction analysis.For the preliminary communication, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1278–1283, July, 1994.This work was supported by the Russian Foundation for Basic Research (project code 93-03-5329). 相似文献
13.
V. L. Rusinov E. N. Ulomskii N. A. Klyuev V. M. Orlov S. V. Shorshnev O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》1992,28(11):1331-1334
Prototropic reactions of 6-nitro-7-oxo-4,7-dihydro-1,2,4-triazolo[5,1-c][1,2,4]triazines is tautomeric as established from photoionization results. The ratios of the tautomers in the gas phase and in solution have been determined by mass and 13C NMR spectroscopy.For Communication 18 see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1555–1559, November, 1992. 相似文献
14.
15.
The kinetics of the reaction of acridine hydrochloride with the alkiodides of 2- and 4-picolines, 2- and 4-methylquinolines, 2-methylbenzothiazole, and 1,2-dimethylbenzimidazole in the presence of air oxygen were investigated. It is shown that the reaction is second order overall and first order in each of the components at a constant oxygen concentration. The reaction rate constants were calculated, and a mechanism is proposed for the reaction. 相似文献
16.
G. L. Rusinov N. I. Latosh I. I. Ganebnykh R. I. Ishmetova N. K. Ignatenko O. N. Chupakhin 《Russian Journal of Organic Chemistry》2006,42(5):757-765
6-R-3-(3,5-Dimethylpyrazol-1-yl)-1,2,4,5-tetrazines with aliphatic, cycloaliphatic, and aromatic amines, and also with NH-heterocycles undergo a nucleophilic substitution of the dimethylpyrazole moiety yielding symmetrically and unsymmetrically substituted 1,2,4,5-tetrazines. In the 3,6-diimidazolyl-and 3,6-dibenzotriazolyl derivatives reactions of nucleophilic substitution of the heterocyclic moiety also occur. In some cases an ipsosubstitution of amino, hydrazino, and azido groups is observed. 相似文献
17.
Kozhevnikov I. S. Kovalev V. L. Rusinov O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》2001,37(9):1136-1140
3-R-6-Phenyl-1,2,4-triazine 4-oxides react with cyclic -diketones (dimethylbarbituric acid, dimedone, and indan) in both acidic (substrate activation) and basic conditions (nucleophile activation) with formation of H-adducts, intermediates in the nucleophilic substitution of hydrogen (SN
H) in 3-R-5-Nu-4-hydroxy-6-phenyl-4,5-dihydro-1,2,4-triazines. Oxidative aromatisation of these intermediates or auto-aromatisation of acylated (benzoyl chloride) at the NOH -adducts with elimination of benzoic acid gave the corresponding substituted 1,2,4-triazine 4-oxides or 1,2,4-triazines. 相似文献
18.
Reaction of N-methylquinoxalinium iodide with nitroethane results in either the 1:2 diadduct at C-2 and C-3 or the formation of substituted 1,3,6,10-tetraazatetracyclo[7.3.1.0.2,706,13] tridecane derivative. 相似文献
19.
Khabibulina I. V. Trifonov R. E. Volovodenko A. P. Eremenkova M. S. Chupakhin O. N. Rusinov V. L. Zyryanov G. V. Ostrovskii V. A. 《Russian Journal of Organic Chemistry》2004,40(3):426-430
The acidity and basicity constants of isomeric phenyl(aryl)-1,2,4-triazin-3- and -5-ones in aqueous solution were determined by spectrophotometry: pK
a = 7.3–6.2; pK
BH+= 0.1 to –2.2. 1,2,4-Triazin-3-ones are weaker bases than the corresponding 1,2,4-triazin-5-ones. According to the AM1 calculations, the most thermodynamically favorable tautomer in the gas phase is the oxo form: namely, 2H-tautomers of the neutral bases and 2,4-H,H
+-tautomers of the conjugate acids. 相似文献
20.
V. I. Saloutin Z. E. Skryabina Y. V. Burgart O. N. Chupakhin M. Font-Altaba X. Solans M. Font-Bardia 《Russian Chemical Bulletin》1993,42(10):1697-1700
The transamination of 2-amino-4-imino-2-perfluoropentene with ethylenediamine gives the corresponding 6-fluoro-5,7-bis(trifluoromethyl)-2,3-dihydro-1H-1,4-diazepine. The transamination of 2-amino-4-imino-2-perfluoropentene by diethylenetriamine is accompanied by intramolecular
nucleophilic substitution of the α-fluorine atom to form 1,9-bis(trifluoromethyl)-3,4,6,7-tetrahydro-2H-pyrazino[1,2-a]pyrazine whose structure was established by an X-ray structural investigation. Several salts of this bicyclic compound and
its complex with BF3 have been described.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1773–1776, October, 1993. 相似文献