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91.
Yu. A. Borisov Yu. A. Zolotarev E. V. Laskatelev N. F. Myasoedov 《Russian Chemical Bulletin》1997,46(3):407-409
The simplest quantum-chemical models of hydrogen spillover over a graphite-like surface as a proton or radical have been considered.
The condensed planar C24H12 molecule was used as a model surface. Theab initio calculations of the interaction of hydrogen with the model surface were carried out by the restricted Hartree-Fock (HF) method
in the STO-3G and 6-31 G* basis sets. The radical hydrogen can not bind to such a surface, whereas the proton binds to it with an energy release of
186 kcal mol−1. The activation energy of the transfer of the proton between two neighboring carbon atoms (10 kcal mol−1) has been determined. The simplest model of the hydrogen migration as a proton over the model surface can be used for describing
the spillover of hydrogen over the graphite surface.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 428–430, March, 1997. 相似文献
92.
A. V. Varlamov D. G. Grudinin A. I. Chernyshev A. N. Levov N. I. Golovtsov R. S. Borisov 《Chemistry of Heterocyclic Compounds》2001,37(3):346-352
4,5-Dihydro-5-methyl-3H-spiro[benz-2-azepine-3-cyclohexane] N-oxide reacted with cyanide ion and isopropyl magnesium bromide to give the corresponding 1-cyano- and 1-isopropyl-4,5-dihydro-5-methyl-3H-spiro[benz-2-azepine-3-cyclohexane], but reaction with phenyl magnesium bromide, benzyl magnesium chloride, and nitromethane gave cyclic hydroxylamines: 1-substituted N-hydroxy-1,2,4,5-tetrahydro-5-methyl-3H-spiro[benz-2-azepine-3-cyclohexanes] which were oxidized to the corresponding nitrones. 相似文献
93.
V. A. Borisov A. N. D’yachenko R. I. Kraidenko 《Russian Journal of Inorganic Chemistry》2012,57(7):923-926
A reaction between cobalt oxide and ammonium chloride was studied. A possible mechanism of this reaction was determined by TGA and DSC. The reaction products were identified by IR spectroscopy, chemical and XRD analyses. A multistage mechanism was established for reaction between cobalt oxide and ammonium chloride. Cobalt chloride was determined to be the final product; the reaction occurs via the formation and decomposition of (NH4)3CoCl5, (NH4)2CoCl4, and NH4CoCl3. 相似文献
94.
Quantum yields () for the generation of singlet oxygen sensitized by Pd(II) complexes of water-soluble porphyrins: meso-tetrakis(4-N-methylpyridyl)porphine [PdTMPyP]4+ ( = 0.9), meso-tetrakis(4-N,N,N-trimethylaminophenyl)porphine [PdTTMAPP]4+ ( = 0.8), meso-tetrakis(4-carboxyphenyl)porphine [PdTCPP]4– ( = 0.7), and meso-tetrakis(4-sulfonatophenyl)porphine [PdTSPP]4– ( = 0.5) were determined using a chemical method. It was found that the dimerization and aggregation of metalloporphyrins greatly influence the value. The quantum yields evaluated for the formation of singlet oxygen sensitized by metalloporphyrin monomeric and dimeric forms are , M 0.9 and , D 0.2, respectively, and do not depend on the porphyrin nature. 相似文献
95.
L. A. Borisov 《Journal of Mathematical Sciences》1999,94(1):1073-1099
This paper proves that there are only finitely many subgroupsH of finite index in Sp(4,Z) such that coresponding quotient
of the Siegel upper half space of rank two is not of general type.
Translated from Itogi Nauki i Tekhniki, Seriya Sovremennaya Matematika i Ee Prilozheniya. Tematicheskie Obzory. vol. 56. Algebraic
Geometry-9, 1998. 相似文献
96.
S. V. Borisov N. A. Bliznyuk N. V. Podberezskaya E. S. Kuklina 《Journal of Structural Chemistry》1995,36(3):439-444
Five fluoride structures differing in the character of linkage of cationic polyhedra and in relative water contents are considered. The cationic sublattice is four-layered (ABAC) in K2Cu(ZrF6)2·6H2O, face-centered (F-type, ABC) in CuZrF6·4H2O primitive cubic (P-type) in Cu3(ZrF7)2·16H2O, hexagonal one-layered (AA) in Cu2ZrF8·12H2O and hexagonal two-layered (AB) in Zr2F8·6H2O. Some structures have considerably distorted symmetries of cationic sublattices compared to anhydrous structures because of the anisotropy of cation surroundings in the first, second, and third spheres, but al characteristic close-packed cation planes of the corresponding structural types are retained. In structures with cation-cation distances of ~3.5 Å, dimeric cations are arranged as single fragments for planes with dhkl>3.5 Å or as separate fragments for planes with smaller dhkl. 相似文献
97.
98.
99.
100.
Condensation of 1-alkyl-2-aminoindoles with malonic ester gives -carbonyl derivatives which, on the basis of the their UV, IR, and NMR spectra, and their chemical properties, are assigned the 2-oxo-4-hydroxy--carboline structure.For Part XVIII, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1207–1211, September, 1970. 相似文献