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101.
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103.
Koval IA Gamez P Roubeau O Driessen WL Lutz M Spek AL Reedijk J 《Inorganic chemistry》2003,42(3):868-872
The structure, spectroscopy, and magnetism of a century-old copper salt, Cu(OAc)(OMe), is reported. The crystal structure contains two independent Cu(II) ions, which are both five-coordinated and which are bridged by methoxo and acetate anions to form an infinite 2D network. Thereby the methoxo groups connect Cu1 and Cu2 with their symmetry-generated counterparts Cu1(i) and Cu2(i), respectively, resulting in Cu.Cu distances of 2.9803(10) and 2.9874(10) A. Cu1 and Cu2 themselves are bridged via the carboxylate groups of two acetates leading to a Cu1.Cu2 distance of 2.9473(7) A. The tetranuclear units thus generated are cross-linked via acetate oxygens to form a 2D sheet structure. One of the two independent acetate ligands has a rare binding mode, whereby it acts as a tetradentate syn-anti, syn-anti bridging ligand. The temperature dependence of the magnetic susceptibility was assigned to be dominated by the very strong antiferromagnetic exchange coupling via bis(mu-methoxo) bridges (J(1) = -409(1) cm(-)(1)). 相似文献
104.
Koolhaas GJ Driessen WL Reedijk J van Der Plas JL de Graaff RA Gatteschi D Kooijman H Spek AL 《Inorganic chemistry》1996,35(6):1509-1517
The synthesis and characterization of three dinuclear copper(II) complexes and one mixed-valence tetranuclear cluster with the asymmetric imidazole-containing ligand bis(1,1'-imidazole-2-yl)(4-imidazole-4(5)-yl)-2-azabutane (biib) are described. X-ray crystallographic parameters for the copper complexes are as follows. [Cu(2)(biib)(2)(BF(4))(2)](BF(4))(2)(H(2)O)(4): triclinic, space group P&onemacr;, a = 10.178(1) ?, b = 9.4881(9) ?, c = 11.037(1) ?, alpha = 95.130(10) degrees, beta = 112.20(1) degrees, gamma = 92.142(9) degrees, and Z = 1. [Cu(2)(biib)(2)(NO(3))(2)](NO(3))(2)(H(2)O)(4): monoclinic, space group &Pmacr;2(1)/n, a = 9.207(6) ?, b = 17.0516(6) ?, c = 12.6107(7) ?, beta = 109.82(1) degrees, and Z = 2. [Cu(2)(biib)(2)(CuBr(3))(2)]: monoclinic, space group P2(1)/c, a = 11.583(2) ?, b = 11.864(2) ?, c = 16.070(2) ?, beta = 112.459(12) degrees, and Z = 2. The two Cu(II) ions in all four complexes are coordinated in a square-pyramidal geometry by three imidazole nitrogens and one amine nitrogen donor in the equatorial plane, and each copper ion is weakly coordinated at the axial position by respectively a tetrafluoroborate, a perchlorate, a nitrate, or a tribromocuprate(I) anion. By comparison of the structural data of the four complexes a relationship has been established between the donor strength of the anion and some structural features, like the Cu(II)-Cu(II) distance, of the dinuclear Cu(II)-Cu(II) unit in the four complexes. Single-crystal EPR spectra of [Cu(2)(biib)(2)(BF(4))(2)](BF(4))(2)(H(2)O)(4) were recorded at room temperature at X-band frequencies. The triplet spectra have been fit with nonparallel g and D tensors, whose principle values are as follows: g(xx)() = 2.022(8), g(yy)() = 2.060(7), g(zz)() = 2.211(8), D(x)()(')(x)()(') = -0.0182(9) cm(-)(1), D(y)()(')(y)()(') = -0.081(6) cm(-)(1), D(z)()(')(z)()(') = 0.0264(7) cm(-)(1). The compounds were further characterized and studied by ligand field and by frozen-solution and polycrystalline powder EPR spectroscopy. EPR spectra recorded at 77 K of frozen solutions of the perchlorate complex show that upon dilution in methanol the dinuclear complex reacts to form a mononuclear species. 相似文献
105.
Jos Terheijden Willem L. Driessen Willem L. Groeneveld 《Transition Metal Chemistry》1980,5(1):346-350
Summary Several new coordination compounds are reported withN-carbamoylpyrazole (Hcpz) as the ligand;viz. M(cpz)2 where M = CuII and NiII; M(Hcpz)Cl2 where M = MnII, CoII, CuII, ZnII and CdII; M(Hcpz)2Cl2 Where M = FeII, CoII and NiII: M(Hcpz)3(BF4)2 where M = FeII, CoII, NiII, ZnII and CdII; and Cu(Hcpz)2(BF4)2. In the salts, Hcpz is coordinated through the nitrogen atoms of the pyrazole ring and the nitrogen atom of the carbamoyl group. In the Hcpz complexes, coordination takes place through the nitrogen atom of the pyrazole ring and the oxygen atom of the carbamoyl group. 相似文献
106.
The useful reactivity of AlCl3 and AlBr3 σ-complexes of cyclobutadienes towards various reagents is demonstrated. In reactions with acetylenic derivatives (affording dewarbenzenes), nitriles (affording pyridines in the case of ethylcyanoformate) and sulfur dioxide, cycloadditions to liberated cyclobutadienes are possibly involved; in reactions with isocyanides a nucleophilic attack at the allylic moiety of the σ-complexes appears to take place. The reactivity differences between the tetramethyl- and the 3,4-dimethyl-1,2-tetramethylene-substituted complexes are pointed out. A novel route to dibromocyclobutene derivatives employing AlBr3 σ-compIexes of cyclobutadienes is presented. 相似文献
107.
108.
Stolwijk D Driessen EF Verschuuren MA 't Hooft GW van Exter MP de Dood MJ 《Optics letters》2008,33(4):363-365
We compare the angle-dependent transmission spectra of a metal hole array with dielectric pillars in each hole with that of a conventional metal hole array. The pillars enhance the optical transmission as well as the interaction between surface plasmon modes. This results in an observed splitting Delta omega/omega as large as 6%, at normal incidence, for the modes on the pillar side of the array. 相似文献
109.
Willem L. Driessen Marinus den Heijer Nico van Gils Willem L. Groeneveld 《Transition Metal Chemistry》1981,6(5):296-297
Summary Eighteen new coordination compounds are reported with diglyme (dgm) and pentaglyme (pgm) as ligands:viz. [M(dgm)2](SbCl6)2 with M=MgII, CaII, SrII, MnII, FeII, CoII, NiII, CuII, and ZnII; [M(pgm)](SbCl6)2 with M=MnII, FeII,CoII, NiII, CuII, and ZnII; and [M(pgm)](SbCl6)2 · H2O with M=MgII, CaII, and SrII. The metal(II) ions are hexacoordinated by the ether-oxygens of two diglyme molecules or of one pentaglyme molecule. The coordinated diglyme molecules are in the TGTT¯GT conformation. 相似文献
110.
Patrick J. Baesjou Willem L. Driessen Ger Challa Jan Reedijk 《Journal of molecular catalysis. A, Chemical》1999,140(3):102-253
The kinetics of the copper/N-methylimidazole catalysed oxidative coupling reaction with the C–O coupled dimer of 2,6-dimethylphenol (DMP or monomer), viz. 4-(2′,6′-dimethylphenoxy)-2,6-dimethylphenol (dimer), as the substrate have been studied. The reaction was found to obey Michaelis–Menten kinetics. The dimer is more easily oxidised than the monomer, but the formation of a copper–substrate complex is more difficult. The reaction rates are higher than in the case of the monomer, and the amounts of diphenoquinone (DPQ) formed are much lower. With the dimer as the substrate, the order of the reaction in copper is 2, confirming that the formation of a dinuclear copper complex is an important step in the reaction mechanism. The amount of DPQ formed is proportional to the initial amount of the dimer. A slight, but clear preference for the dimer over the monomer as the substrate has been observed from experiments with mixtures of monomer and dimer. The amount of DPQ formed decreases exponentially with an increase in the fraction of dimer in the mixture, which can be ascribed mainly to a statistical effect. 相似文献