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991.
Zaqueu Coelho Anthony N. Quas 《Transactions of the American Mathematical Society》1998,350(8):3257-3268
Bernoullicity is the strongest mixing property that a measure-theoretic dynamical system can have. This is known to be intimately connected to the so-called metric on processes, introduced by Ornstein. In this paper, we consider families of measures arising in a number of contexts and give conditions under which the measures depend -continuously on the parameters. At points where there is -continuity, it is often straightforward to establish that the measures have the Bernoulli property.
992.
Martijn J.J. Mulder Huub Kooijman Anthony L. Spek Jaap. G. Haasnoot Jan Reedijk 《Journal of chemical crystallography》2002,32(9):347-351
The crystal structure of the title compound, tetrabutylammonium bis(2-thioxo-1,3-dithiole-4,5-dithiolato)nickelate(III), [N(C4H9)4][Ni(C3S5)2], is the fourth known phase of this polymorphous compound. It is monoclinic space group P21/c, with a = 20.040(2) Å, b = 13.1151(17) Å, c = 12.1093(15) Å, = 105.456(15)°, and V = 3067.5(6) Å3 with Z = 4, for D
calc = 1.503 g cm–3. The [Ni(dmit)2] anion packing arrangement consists of arrays of side-on touching anions and these arrays are connected via head-to-tail close S S contacts. 相似文献
993.
Arno F. Stassen Huub Kooijman Anthony L. Spek Jaap G. Haasnoot Jan Reedijk 《Journal of chemical crystallography》2001,31(6):307-314
The compounds hexakis(1-(2-chloroethyl)-tetrazole-N4)copper(II) tetrafluoroborate mono(1-(2-chloroethyl)-tetrazole) (1) and hexakis(1-(2-chloroethyl)-tetrazole-N4) copper(II) perchlorate mono(1-(2-chloroethyl)-tetrazole) (2) were obtained from the crystallization of 1-(2-chloroethyl)-tetrazole (teec) with the respective copper salt. The X-ray structures are reported. Both compounds crystallize in the monoclinic space group C2/c for 1: a = 25.754(3) Å, b = 18.162(3) Å, c = 10.298(2) Å = 104.294(7)° and Z = 4 and for 2: a = 25.745(3) Å, b = 18.197(3) Å, c = 10.29355(3) Å = 104.512(10)° and Z = 4. The CuII ions are octahedrally surrounded by six teec ligands. One free teec ligand is present in the structures. The Cu–N distances in the centrosymmetrical units are 2.01, 2.04, and 2.39 Å in both compounds, consistent with a Jahn–Teller elongated octahedron. The ligand field spectra of both compounds show a signal in the visible range at about 15.200 cm–1 and by an EPR spectrum the following values are found: g
| = 2.29 and g = 2.03. The compounds are both paramagnetic and the T value of 0.37 cm–1 K mol–1, which is associated with S = 1/2, is what would be expected for a mononuclear CuII complex. 相似文献
994.
Gerard A. van Albada Wilberth J.J. Smeets Anthony L. Spek Jan Reedijk 《Journal of chemical crystallography》2000,30(7):441-444
The compound [Fe(bipym)33](CF3SO3)2 (in which bipym = 2,2-bipyrimidine) crystallizes in the space group P21/c, with a = 13.7641(11), b = 18.7557(19), c = 12.3627(11) Å, = 103.085(8)° and Z = 4. The low-spin Fe(II) atom is octahedrally surrounded by six nitrogen atoms of three bipyrimidine groups with Fe—N distances that vary from 1.968(4) to 1.975(4) å. In the far-infrared region the Fe—N vibrations are observed at 359 and 372 cm-1. 相似文献
995.
Anghelescu AV DeLisle RK Lowrie JF Klon AE Xie X Diller DJ 《Journal of chemical information and modeling》2008,48(5):1041-1054
We describe and demonstrate a method for the simultaneous, fully flexible alignment of multiple molecules with a common biological activity. The key aspect of the algorithm is that the alignment problem is first solved in a lower dimensional space, in this case using the one-dimensional representations of the molecules. The three-dimensional alignment is then guided by constraints derived from the one-dimensional alignment. We demonstrate using 10 hERG channel blockers, with a total of 72 rotatable bonds, that the one-dimensional alignment is able to effectively isolate key conserved pharmacophoric features and that these conserved features can effectively guide the three-dimensional alignment. Further using 10 estrogen receptor agonists and 5 estrogen receptor antagonists with publicly available cocrystal structures we show that the method is able to produce superpositions comparable to those derived from crystal structures. Finally, we demonstrate, using examples from peptidic CXCR3 agonists, that the method is able to generate reasonable binding hypotheses. 相似文献
996.
Martin Lutz Anthony L. Spek Erwin P. L. van der Geer Gerard van Koten Robertus J. M. Klein Gebbink 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(2):o87-o90
The cation of the title compound, C13H18N3S+·NO3−, consists of two subunits, viz. a planar indole moiety and a nonplanar thiouronium moiety. An isolated intermolecular hydrogen bond connects the cation with the nitrate anion. The crystal packing is additionally characterized by short intermolecular contacts between parallel indole systems. A topological analysis of the electron density revealed C—S single bonds and partial double bonding in the N—C—N group. 相似文献
997.
Harinandini Paramahamsan Anthony J. Pearson Nathalie M. Pinkerton A. Alan Pinkerton 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(4):m147-m148
The tricarbonylchromium unit bound to the arene ring of the chiral title complex, [Cr(C19H26O3)(CO)3], is rotated by ca 25° in agreement with the proposed mechanism for 1,5‐asymmetric induction of nucleophilic attack. 相似文献
998.
Anthony Joseph 《Journal of Algebra》2008,319(12):5060-5100
999.
Wu G Norris C Stewart H Cox H Stace AJ 《Chemical communications (Cambridge, England)》2008,(35):4153-4155
A combined theoretical and experimental study of electronic transitions in the complex [Zn(pyridine)(4)](2+) provides the first example of a state-resolved electronic spectrum to be recorded for a dication complex in the gas phase. 相似文献
1000.