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991.
A. A. Akhrem L. I. Ukhova G. V. Bludova T. M. Tsvetkova G. I. Trus N. I. Garbuz L. P. Solovei 《Chemistry of Heterocyclic Compounds》1976,12(1):90-95
Isomeric 1-alkyl-2-methyl-4- (haloethynyl) decahydro-4-quinolols were synthesized by reaction of the individual stereoisomers of 1-alkyl-2-methyl-4-ethynyl-decahydro-4-quinolols with alkali solutions of potassium hypochlorite and hypobromite. 1-Chloro-2-methyl-4-ethynyl decahydro-4-quinolols are formed by the action of an alkaline solution of potassium hypochlorite on isomeric 2-methyl-4-ethynyldecahydro-4-quinolols. Hydrogenolysis of the carbon-halogen bond accompanied by hydrogenation of the CC bond was observed under conditions of catalytic hydrogenation of 1,2-dimethy1-4-(haloethynyl) decahydro-4-quinolols. Primarily hydrogenolysis of the nitrogen-halogen bond and subsequent reduction of the acetylenic bond occur in the hydrogenation of 1-chloro-2-methyl-4-ethynyldecahydro-4-quinolols. Replacement of chlorine by hydrogen and subsequent alkylation of the resulting secondary amine and formation of the hydrochlorides of the corresponding N-methyl-substituted acetylenic alcohols occur in the reaction of the chloramines with a mixture of formaldehyde and formic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 98–103, January, 1976. 相似文献
992.
E. Silina J. Ashaks S. Belyakov L. Pech Yu. Bankovsky 《Chemistry of Heterocyclic Compounds》2006,42(3):352-357
The molecular and crystal structure of palladium quinoline-8-selenolate Pd(C9H6NSe)2 has been determined by X-ray structural analysis. The structures of the five-membered metallocycles of palladium 8-hydroxy-,
8-mercapto-, and 8-hydroselenoquinolinates of one type are compared.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 396–402, March, 2006. 相似文献
993.
P. V. Klevtsov L. A. Glinskaya R. F. Klevtsova K. S. Aleksandrov 《Journal of Structural Chemistry》1997,38(4):615-619
Single crystals of CsNaMoO4 · 2H2O were synthesized, and the crystal structure of this compound was determined from X- ray diffraction data (SYNTEX P21 automatic diffractometer, MoKα radiation, 2252 reflections, R =0.037). Crystals are orthorhombic, space group P212121 with unit cell dimensions a =6.379(1), b =8.625(1), c =13.671(2) å, Z =4. The structure of the binary molybdate consists of continuous columns of face- sharing Na octahedra with attached MoO4 tetrahedra. The neighboring columns are linked by the Cs cations and the hydrogen bonds of the water molecules entering into the coordination polyhedra of the Na and Cs atoms. 相似文献
994.
A mathematical framework for translational Brownian motion on hypersurfaces is presented, using an imbedding of the surface and Ito diffusions in the ambient space. This includes a survey of Ito calculus and differential geometry. Computational methods for time correlation functions relevant to spin relaxation studies on curved interfaces are given, and explicit calculations of time correlation functions and order parameters for a Rippled surface are presented. 相似文献
995.
The crystal structure of HLiTa3O8 has been reexamined by electron and neutron diffraction techniques. Neutron Weissenberg and electron diffraction photographs show that the space group of the compound isPmmn and notPmma as determined previously by X-ray diffraction techniques. There are eight molecules in the unit cell of lattice parametersa = 16.718(2)A?,b = 7.696(1)A?,c = 8.931(1)A?. These values show that thebaxis of the new cell is doubled with respect to the parameter measured by X-rays. The structural refinement was based on 1074 independent reflections measured on a single crystal with a four-circle neutron diffractometer. The positions of all atoms, including the lithium atoms have been determined. The finalR andwRfactors were 0.036 and 0.035, respectively. The eight lithium cations occupy two sets of4fpositions(x,¼, z)of thePmmn space group. The ordering of four lithium ions over two sets of possible positions (4j) of space groupPmma is responsible for the doubling of theb axis. The other four Li+ occupy two sets of positions (2d) of space groupPmma. All lithium ions are surrounded by 12 oxygen atoms arranged as cuboctahedra. The large thermal vibrations found for the lithium atoms and the ionic conductivity of HLiTa3O8 at high temperatures are consistent with weak LiO bonding. 相似文献
996.
997.
L. V. Mikheiskaya R. G. Ovodova E. L. Golynskaya T. V. Yurchishina Yu. S. Ovodov 《Chemistry of Natural Compounds》1977,12(3):251-254
Summary It has been shown that the phytohemagglutinins of maize stigmata consist of carbohydrate-protein compounds and that the carbohydrate and protein components have a fairly strong bond. The nature of this bond remains unknown.The phytohemagglutins isolated possess a well-defined agglutinating and mitotic activity.Pacific-Ocean Institute of Bioorganic Chemistry, Far-Eastern Scientific Center of the Academy of Sciences of the USSR, Vladivostok. A. V. Fomin Botanical Gardens, T. G. Shevchenko Kiev State University. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 281–285, May–June, 1976. 相似文献
998.
The IR and Raman spectra of a number of anions of the nitro derivatives of 1,2,4-triazole were investigated. On the basis of the position of the absorption maxima of the asymmetric and symmetric t vibrations of the nitro group, it is assumed that the nitro groups in the 3 and 5 positions of the triazole ring are coplanar, which should lead to an increase in the participation of the nitro group in the de localization of the negative charge of the anion. Shifts of the frequencies as a function of the nature of the cation (NH4, Na, K, Cs) were not detected in the IR spectra of the crystalline salts. In addition, the IR spectra of the crystalline salts are similar (with respect to the frequencies) to the spectra of aqueous solutions of the salts, which may serve as proof of the identical structure of the anions in crystals and aqueous solutions.See [1] for communication XII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 120–123, January, 1972. 相似文献
999.
1000.