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101.
Christian Albrecht Christoph Wagner Kurt Merzweiler Tadeusz Lis Dirk Steinborn 《应用有机金属化学》2005,19(11):1155-1163
The platina‐β‐diketone [Pt2{(COMe)2H}2(µ‐Cl)2] ( 1 ) was found to react with monodentate phosphines to yield acetyl(chloro)platinum(II) complexes trans‐[Pt(COMe)Cl(PR3)2] (PR3 = PPh3, 2a ; P(4‐FC6H4)3, 2b ; PMePh2, 2c ; PMe2Ph, 2d ; P(n‐Bu)3, 2e ; P(o‐tol)3, 2f ; P(m‐tol)3, 2g ; P(p‐tol)3, 2h ). In the reaction with P(o‐tol)3 the methyl(carbonyl)platinum(II) complex [Pt(Me)Cl(CO){P(o‐tol)3}] ( 3a ) was found to be an intermediate. On the other hand, treating 1 with P(C6F5)3 led to the formation of [Pt(Me)Cl(CO){P(C6F5)3}] ( 3b ), even in excess of the phosphine. Phosphine ligands with a lower donor capability in complexes 2 and the arsine ligand in trans‐[Pt(COMe)Cl(AsPh3)2] ( 2i ) proved to be subject to substitution by stronger donating phosphine ligands, thus forming complexes trans‐[Pt(COMe)Cl(L)L′] (L/L′ = AsPh3/PPh3, 4a ; PPh3/P(n‐Bu)3, 4b ) and cis‐[Pt(COMe)Cl(dppe)] ( 4c ). Furthermore, in boiling benzene, complexes 2a – 2c and 2i underwent decarbonylation yielding quantitatively methyl(chloro)platinum(II) complexes trans‐[Pt(Me)Cl(L)2] (L = PPh3, 5a ; P(4‐FC6H4)3, 5b ; PMePh2, 5c ; AsPh3, 5d ). The identities of all complexes were confirmed by 1H, 13C and 31P NMR spectroscopy. Single‐crystal X‐ray diffraction analyses of 2a ·2CHCl3, 2f and 5b showed that the platinum atom is square‐planar coordinated by two phosphine ligands (PPh3, 2a ; P(o‐tol)3, 2f ; P(4F‐C6H4)3, 5b ) in mutual trans position as well as by an acetyl ligand ( 2a, 2f ) and a methyl ligand ( 5b ), respectively, trans to a chloro ligand. Single‐crystal X‐ray diffraction analysis of 3b exhibited a square‐planar platinum complex with the two π‐acceptor ligands CO and P(C6F5)3 in mutual cis position (configuration index: SP‐4‐3). Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
102.
Tadeusz Rzezuchowski 《Set-Valued Analysis》1997,5(2):181-193
The solutions of differential inclusions staying at the boundary of attained sets are investigated using the contingent cones to attained sets. The possibility of recovering the starting point and the time which elapsed since the beginning is shown when some fragments of an attained set are known. 相似文献
103.
An implementation of the p‐version of the finite element method for solving two‐dimensional linear elliptic problems on a shared‐memory parallel computer
is analyzed. The idea is to partition the problem among the available processors and perform computations corresponding to
different elements in parallel. The parallelization is based on a domain decomposition technique using the Lagrange multipliers.
The numerical experiments carried out on the Sequent system indicate very high performance of the mixed finite element algorithm
in terms of attained speedups.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
104.
A general equation for calculating the limit of the ligand interference region with the non-stoichiometric copper sulphide single-crystal electrode is described. The critical ligand concentration can be computed for a preselected maximal error in copper(II) ion determinations. The effect of the composition of the electrode material is discussed. The experimental results for the chloride interference show good agreement with theoretical predictions. 相似文献
105.
Quasiregular mappings in even dimensions 总被引:39,自引:0,他引:39
106.
Dilithium tetrabromonickelate (II) as a source of soft nucleophilic bromide : Reaction with epoxides
Dilithium tetrabromonickelate (II) in THF serves as a source of “soft” nucleophilic bromide and reacts regioselectively with epoxides to give bromohydrins in high yield. 相似文献
107.
An isomorphism is established between eertain compact and noncompact formulations of Abelian gauge theory on a lattice. For weak coupling, the mass gap predicted by the Higgs mechanism is then established. 相似文献
108.
Three types of porous polymers containing different functional groups were synthesized as stationary phases for gas chromatography. The influence of functional groups in the copolymer skeletons on their selectivities was studied. To determine the selectivities of these copolymers, two procedures were applied: the selectivity triangle and the general selectivity. As a reference phase Porapak Q which does not contain any functional groups was used. 相似文献
109.
Tadeusz Bałaban 《Communications in Mathematical Physics》1983,88(3):411-445
This is the third paper of a series, and contains a proof of the bounds on the effective actions needed in the two previous papers. The proof is based on perturbative analysis of renormalization. 相似文献
110.
Tadeusz M. Krygowski Piotr K. Wrona Urszula Zielkowska Christian Reichardt 《Tetrahedron》1985,41(20):4519-4527
Empirical parameters of Lewis acidity, ENT, introduced by Reichardt et al., and Lewis basicity, BKT , introduced by Kamlet and Taft, have been determined for mixtures of water with ten organic solvents. In the case of water/alcohol mixtures a distinct dependence between these acidity and basicity parameters have been found. For the other solvent mixtures the ENT on BKT dependence is more complex even if these parameters are purified from non-specific solute/solvent interactions. 相似文献