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1.
The effect of a substituent in the triazole ring and of the composition of the solvent on the reaction rate was established as a result of a study of the kinetics of methylation of sodium salts of 3(5)-nitro-1,2,4-triazoles in water and water-dioxane mixtures. The relationships found are due to the different degree of dissociation of intimate ion pairs of anions of nitrotriazoles with sodium and the specific character of the solvation of the anions by water. 相似文献
2.
V. A. Petrosyan M. E. Niyazymbetov M. S. Pevzner B. I. Ugrak 《Russian Chemical Bulletin》1988,37(7):1458-1461
Conclusions The electrolytic oxidation of the 3-nitro-1,2,4-triazole anion is realized through an intermediate radical, which splits out an H atom on reaction with the medium and reacts with benzene to give N-substituted phenyl-3-nitro-1,2,4-triazoles.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1643–1646, July, 1988. 相似文献
3.
Shul'gin V. F. Pevzner N. S. Zub V. Ya. Strizhakova N. G. Maletin Yu. A. 《Russian Journal of Coordination Chemistry》2004,30(10):723-726
X-ray diffraction analysis of the copper(II) chelate complex CuL2 (where L is the deprotonated imid-ol form of N,N-dimethyl-2,4-dichlorophenoxyacetohydrazide (HL)) was performed (3826 reflections, R = 0.039, wR = 0.043). Crystals are monoclinic, a = 8.365(7) Å, b = 23.090(7)Å, c = 12.713(3) Å, = 95.12(6)°, space group P21/c, Z = 4. The slightly distorted square environment of the copper cation is composed of two N atoms of the dimethylamino groups and two O atoms of the deprotonated imidol groups. Both N and O atoms are located in trans-positions relative to each other. Additional coordination of electron-donor atoms is prevented by methyl groups, in which the C atoms are at a distance of 2.837 to 2.918 Å from the central ion. 相似文献
4.
M. A. Pervozvanskaya M. S. Pevzner L. N. Gribanova V. V. Mel'nikov B. V. Gidaspov 《Chemistry of Heterocyclic Compounds》1977,13(12):1335-1337
The dipole moments of indazole and a number of its nitro derivatives in dioxane solution were measured. The directions of the vectors of the dipole moments of indazole in the tautomeric 1-H and 2-H forms were determined to solve the problems associated with the tautomerism and the position of the substituents in the molecules. The experimental values of the dipole moments, of the investigated compounds were compared with the values calculated via a vector additive scheme. As a result it was shown that the mononitro and dinitro derivatives of indazole exist primarily in the 1-H tautomeric form, whereas the trinitro and tetranitroindazoles exist in the 2-H tautomeric form. The ratios of the isomers were calculated for compounds that have dipole moments intermediate between the 1-H and 2-H forms. A deviation between the experimental and calculated dipole moments of compounds containing two nitro groups in the ortho position was established; this may be explained by disruption of the coplanarity of the molecules or by deviation from additivity because of the introduction of strong electron-acceptor substituents.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1669–1671, December, 1977. 相似文献
5.
L. M. Pevzner 《Russian Journal of General Chemistry》2006,76(4):621-625
2-(1-Chloroethyl) and 2-(1-chloro-2-methylpropyl)furans react with sodium diethyl phosphite to give two products, 2-(1-diethoxyphosphorylmethyl)furan and 2-alkyl-5-(diethoxyphosphoryloxy)furan. The fraction of the latter product increases with increasing size of the alkyl radical. 2-Methyl substitution in the substrate completely suppresses phosphate formation. 2-(1-Chloroethyl)-5-(2-methylpropyl)furan under the action of sodium diethyl phosphite eliminates hydrogen chloride to give the corresponding alkene. 相似文献
6.
7.
A synthetic approach to -(chloromethyl)furans with free 2, 5 positions is developed. It isshown that these compounds enter the Michaelis-Becker reaction to form usual phosphorylation products.With 3,4-bis(diethoxyphosphorylmethyl)furan, two conformers with different chemical shifts of phosphorus nuclei and PCH2 protons were detected. 相似文献
8.
T. P. Kofman V. I. Manuilova M. S. Pevzner T. N. Timofeeva 《Chemistry of Heterocyclic Compounds》1975,11(5):612-614
Alkylation of 3,5-dinitro-1,2,4-triazole with -epoxides in aprotic media gave a number of 1-(2-hydroxyalkyl)-3,5-dinitro-1,2,4-triazoles, which readily undergo intramolecular cyclization with elimination of HNO2 to give 5,6-dihydrooxazolo[3,2-b]-1,2,4-triazole derivatives.See [1] for communication I.Translated from Khimiya Geterotsiklicheskih Soedinenii, No. 5, pp. 705–707, May, 1975. 相似文献
9.
1,3-Dihydrooxazino- and 1,3-dihydrooxazolol[3,2-b]-1,2,4-triazoles were obtained instead of the expected 3-nitro-5-cyano-1,2,4-triazole derivatives in the reaction of 1-oxoalkyl-3,5-dinitro-1,2,4-triazoles with potassium cyanide. Their formation is due to the fact that primary attack by the cyanide anion is not directed at the ring C5 atom but rather at the carbonyl group with subsequent intramolecular replacement of the nitro group.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1403–1405, October, 1981. 相似文献
10.
T. P. Kofman N. Yu. Medvedeva T. L. Uspenskaya M. S. Pevzner 《Chemistry of Heterocyclic Compounds》1977,13(9):1026-1029
Ketones of the 3-nitro-5-R-1,2,4-triazole series react with hydrazoic acid in concentrated sulfuric acid to give triazolyl-substituted acetamides. Acid hydrolysis of the latter leads to 1-aminoalkyl-3-nitro-5-R-1,2,4-triazoles. Intramolecular cyclization with the elimination of HNO2 and the formation of 2-nitro-5,6-dihydro-1H-imidazo[2,3-b]-1,2,4-triazole was noted in the case of 1-(2-aminoethyl)-3,5-dinitro-1,2,4-triazole.See [1] for communication XX.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1271–1273, September, 1977. 相似文献