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11.
Ostroushko A. A. Shubert E. Makarov A. M. Minyaev V. I. Udilov A. E. Elokhina L. V. Aksenova V. I. 《Russian Journal of Applied Chemistry》2003,76(8):1253-1259
The catalytic activity of composites constituted by a porous metallic or ceramic support, intermediate layers of oxide nature, and perovskite coatings, including those doped with silver, was studied in reactions of deep oxidation of CO and organic compounds of various classes. The relationship between the catalytic activity of a composite and its composition and nature of substances being oxidized was analyzed. 相似文献
12.
N. D. Kagramanov A. A. Kutin E. I. Mysov K. N. Makarov L. L. Gervits 《Russian Chemical Bulletin》1990,39(5):925-930
The primary and final products arising from the pyrolysis of perfluoro-2,4-dimethyl-3-ethylpentane, perfluoro-3-isopropyl-4-methyl-2-pentene, perfluoro-2-methyl-3-isopropyl-2-pentene, perfluoro-2,4-dimethyl-3-heptene, and perfluoro-4-methyl-2-pentene have been studied using low-energy mass spectrometry and chromatography-mass spectrometry. Thermal decomposition of hexafluoropropene oligomers, containing perfluoroisopropyl groups attached to a double bond, occurs via loss of a radical pair to form perfluorodienes, as well as via abstraction of a hexafluoropropene molecule from the iso-C3F7 group. A correlation between the principal fragmentation pathway observed under electron impact and the primary process in the main thermolysis pathway was detected only in the case of perfluoro-4-methyl-2-pentene and perfluoro-2,4-dimethyl-3-heptene, which are capable of cleavage of.CF3 and.C2F5 radicals, respectively, to give a single possible allyl radical structure.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1037–1041, May, 1990. 相似文献
13.
V. I. Gol'danskii E. F. Makarov R. A. Stukan 《Theoretical and Experimental Chemistry》1970,3(5):396-400
A formula is obtained which relates the isomer shifts in the Mössbauer spectra to the electronic structure of tin in its compounds. It is shown that these formulas describe the isomer shifts of various kinds of chemical compounds: tetravalent tin with -bonding (tin tetrahalides), tetravalent tin with no -bonding (compounds in which the tin is bound to alkyl, aryl, or metal carbonyl radicals), divalent tin, etc. The formulas are used to analyze the electronic structures of tin in compounds of these classes. It is shown that in tetravalent tin compounds with -bonding the isomer shift in the negative direction (with respect to -Sn) is due to the decreased number of 5s-valence electrons, and in the absence of -bonding, by an increase in the number of 5s-valence electrons. 相似文献
14.
V. A. Makarov A. L. Sedov M. P. Nemeryuk N. P. Solov'ev T. S. Safonova 《Chemistry of Heterocyclic Compounds》1994,30(7):846-850
A method has been developed for the synthesis of some-tetrazolyl--nitroenamines containing various alkoxy or amino substituents in the a position. It is based on the transformation of a pyrimidine ring by sodium azide.Center for Drug Chemistry, All-Union research Institute of Pharmaceutical Chemistry (VNIKhFI), Moscow 119021 Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 976–980, July, 1994 相似文献
15.
V. A. Kiyashko A. K. Popov V. P. Timofeev N. P. Makarov V. Sh. Epstein 《Applied physics. B, Lasers and optics》1985,36(1):53-54
Generation of the second- and fourth-order harmonics of laser radiation is reported in Mg vapor at the forbidden 3s
21
S
o–4s
1
S
o transition. The conversion efficiency for the second-order harmonics has been measured to be 10–2% and for the fourth one 10–8%. 相似文献
16.
17.
N. N. Aleinikov G. K. Vasil'ev S. A. Kashtanov E. F. Makarov Yu. A. Chernyshev 《Russian Chemical Bulletin》1996,45(6):1344-1349
The of photochemical decomposition of XcO4 under the action of UV-radia(ion in the wavelength range of 200–300 nm was investigated. The quantum yield of the formation of oxygen atoms upon XeO4 photodissociation was measured (Ф = 3.6±0.4). The results obtained point to the predominant role of the XeO4 +hv → 4O + Xe photodissociation channel of XeO4. The value of the rate constant of the reaction XeO4 + O → O2 + XeO3 was estimated (<4.5 · 10?16 cm2 s?1). 相似文献
18.
V. A. Petrov V. K. Kunanets K. N. Makarov L. S. German 《Russian Chemical Bulletin》1989,38(3):572-575
Conclusions When perfluorinated tertiary cyclic amines containing a substituent at the nitrogen atom are heated with antimony pentafluoride, they isomerize to the corresponding azomethines.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 646–649, March, 1989. 相似文献
19.
D. A. Makarov N. A. Kuznetsova O. L. Kaliya 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(2):268-274
Acridine dyes were found to exhibit a low light fastness in oxygen-containing aqueous solutions because of photooxidation with the participation of molecular oxygen. The values of the quantum yield for the photooxidation of Acridine Yellow, Acridine Orange, and proflavin acetate at their initial concentration 2 × 10?5 mol/l were determined to be 1.8 × 10?3, 1.5 × 10?3, and 0.8 × 10?3, respectively. It was concluded that the photooxidation of these acridine dyes in dilute solutions results in the formation of primary photoproducts of peroxide nature. For proflav in acetate, as an example, it was demonstrated that the increase of the substrate concentration to 6 × 10?4 mol/l results in a fourfold increase in the quantum yield, a behavior indicative of a change in the photodecomposition mechanism. The rate of the interaction between exited and unexcited proflavin molecules, the process responsible for the photodecomposition of this compound, was found to be ~4 × 107 l/(mol s). The quantum yield for the photooxidation of the proflavin base was estimated to exceed that for the photooxidation of the proflavin monocation by more than an order of magnitude. 相似文献
20.
L. I. Makarov 《Journal of Structural Chemistry》2005,46(4):738-743
Some questions emerged from electronic data processing of molecular structures (graphs) and its fragments have been considered in this work. Quantitative estimations of subgraph positions in molecular graphs are presented and some properties of their maximal common subgraphs are described. 相似文献