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71.
72.
合成并通过单晶衍射表征了3个稀土配合物[LnL(NO3)3(H2O)][LnL(NO3)3(CH3CN)]·2CH3CN(Ln=Ce (1),Pr (2),Nd (3),L=3,4-二甲基吡咯-2-甲酰肼缩PMBP)。3个配合物同构,属于单斜晶系,P21/n空间群,晶胞参数分别为:1:a=1.758 83(9) nm,b= 1.460 61(8) nm,c=2.626 28(14) nm,β=97.800 0(10)°;2:a=1.756 39(15) nm,b=1.459 97(11) nm,c=2.623 1(2) nm,β=97.771(2)°;3:a=1.758 7(2) nm,b=1.463 87(17) nm,c=2.626 3(3) nm,β=97.760(2)°。每个配合物包含2个不同的中性配合物分子。配合物中每个十配位的Ln(Ⅲ)离子与来自酰腙配体L的2个氧原子和1个氮原子,3个双齿配位硝酸根及1个溶剂分子配位,采取双帽四方反棱柱配位构型。乙腈溶液中,配合物1~3具有与配体完全不同的荧光发射,可能由配位荧光增强效应导致。 相似文献
73.
74.
《Journal of Coordination Chemistry》2012,65(1-3):159-169
The synthesis and characterization of a new series of iron(II) clathrochelate complexes, including the first example of a binuclear covalently linked c1athrochelate complex, is reported. The ligand system is based on the bifunctional chelate 2,3-butanedione oxime hydrazone which forms a tris-complex with iron(II). The c1athrochelate is completed by capping the complex with both a boronic acid/oxime capping reaction and a formaldehyde/hydrazone capping reaction. Electrochemical and spectroscopic characterizations of the complexes are discussed. 相似文献
75.
《Journal of Coordination Chemistry》2012,65(10):1743-1757
Reaction between [Re(CO)5Cl] and di-2-pyridyl ketone 2-furoic acid hydrazone (dpkfah) (1) in refluxing toluene gave fac-[Re(CO)3(κ2-N,N-dpkfah)Cl] (2). Spectroscopic and electrochemical measurements disclosed sensitivity of 2 to its surroundings. 1H-NMR measurements showed that the amide proton exchanged with solvent protons, and its chemical shift is solvent and temperature dependent, while the chemical shifts of aromatic protons are solvent and temperature independent. Electronic absorption spectra of 2 divulged two intra-ligand charge transfer transitions (ILCT) in protophilic solvents and a single ILCT transition in non-protophilic solvents. Optical measurements on protophilic solutions of 2 established an equilibrium between 2 and its conjugate base, fac-[Re(CO)3(κ2-N,N-dpkfah-H)Cl]? (3). Thermo-optical measurements confirmed that the interconversion between 2 and 3 and gave ΔG ø values of ?26.48 and 22.99?kJ?mol?1, respectively, for the protonation of DMF and DMSO by 2. Optosensing measurements showed that [MCl2] (M?=?Zn, Cd, or Hg) in concentrations as low as 1.00?×?10?7?mol?L?1 can be detected and determined using protophilic solutions of 2. Electrochemical measurements showed 2 to be more stable in CH3CN than DMF. Single-crystal X-ray structural analysis on fac-[Re(CO)3(κ2-N,N-dpkfah)Cl]?·?acetone (4) obtained from an acetone solution of 2 confirmed the solvent–complex interaction and revealed two symmetry-independent molecules in the asymmetric unit. The extended structure of 4 disclosed parallel stacks connected via a network of classic and non-classic hydrogen bonds. 相似文献
76.
《Journal of Coordination Chemistry》2012,65(16):2811-2819
The synthesis and structure of two Cu(II) complexes, {[Cu2(L1)2]?·?DMF} n (1) and [CuL2(phen)] (2), are described. The dinegative hydrazones are obtained by deprotonation of both phenolic and amide moieties of N′-(5-bromo-2-hydroxybenzylidene)-3,5-dimethoxybenzohydrazide (H2L1) and N′-(2-hydroxybenzylidene)pyrazine-2-carbohydrazide (H2L2). In each complex the planar ligand binds the metal ion via phenolate-O, imine-N, and amide-O. Complex 1 is a polymer in which phenoxo-bridged binuclear Cu(II) units are further joined by equatorial–apical amide-O bridges. The Cu···Cu separations are 3.0306 and 3.8217?Å for the phenolate-O bridged pair and the amide-O bridged pair, respectively. Complex 2 is a monomer where chelating phen displays axial–equatorial bonding, with square-pyramidal Cu(II). 相似文献
77.
《Analytical letters》2012,45(5):293-304
Abstract A number of nitrosamines have been reduced to hydrazines and condensed with 9-anthraldehyde and 9-phenanthraldehyde to give highly fluorescent hydrazones which can be separated by thin layer chromatography and identified using Rf, ultroviolet and mass spectra. 相似文献
78.
Divanadium(Ⅴ) complex [VO(aptch)(μ-OCH3)]2(1) and two monovanadium(Ⅴ) complexes [VO(apfah))(OEt)](2a and 2b,H2aptch = 2-hydroxyacetophenone thiophene-2-car-boxylic hydrazone,H2apfah = 2-hydroxyacetophenone 2-furoic acid hydrazone) have been synthesized and characterized.Single-crystal X-ray diffraction studies reveal that 1 is a cen-trosymmetric dimer bridged by two methoxido O-atoms.Complex 1 crystallizes in the monoclinic crystal system,space groups P21/c with a = 7.4825(4),b = 17.0928(11),c = 11.6961(7) ,β = 98.172(4)o,Z = 2,F(000) = 728,μ = 0.829 mm-1,the final R = 0.0457 and wR = 0.1137 for 2654 observed reflections with I > 2(I).The vanadium(V) is coordinated to the tridentate ligand,ethanol molecule to form a distorted square-pyramidal geometry,complexes 2a and 2b.Although 2a and 2b have the same asymmetric unit,they belong to different space groups.Complex 2a crystallizes in the monoclinic crystal system,space groups P21/n with a = 10.2293(2),b = 15.6660(3),c = 10.6298(2) ,β = 116.259(1)o,Z = 4,μ = 0.676 mm-1;complex 2b crystallizes in the triclinic crystal system,space groups P with a = 8.2808(4),b = 9.4704(5),c = 10.0819(5) ,α = 86.133(3),= 81.956(3),γ = 80.248(3)o,Z = 2 and μ = 0.670 mm-1.The hydrogen bonds are found to exist in 2b only.The crystal structure is stabilized by intermolecular hydrogen bonds of C-H···O. 相似文献
79.
Andjelković K. Šumar M. Ivanović-Burmazović I. 《Journal of Thermal Analysis and Calorimetry》2001,66(3):759-778
Results of our research on synthesis and characterization of complexes with acylhydrazone derivatives are described in this
review paper. Structural characterization of newly synthesized complexes by thermal analysis (TG, DTA, DSC) is particularly
emphasized in this paper. Thermal analysis enabled us to study not only structural changes of substances during thermal treatment,
but also the mode of coordination and degree of deprotonation of acylhydrazones, as well as geometry of the coordination sphere
of complexes, the structure of which had not been determined by X-ray analysis. Topics in this paper are as follows: complexes
of dioxomolybdenum(VI) with tridentate hydrazones, usnic acid derivatives and their Cu(II) complexes, as well as transition
metal complexes with 2,6-diacetylpyridine bis(hydrazones).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
80.
合成了一种新的吡咯腙探针1,用于Hg2+的比色和荧光开启检测。探针1对Hg2+的检测限为45 nmol·L-1,缔合常数为5.78×108 L·mol-1。值得注意的是,工作pH范围为4.0~10.0。Job曲线和MS数据证实探针与Hg2+形成1:1的配合物。通过1H NMR、时间分辨荧光光谱和密度泛函理论(DFT)计算系统研究了探针与Hg2+的配位模式。此外,由于吗啉基团的存在,探针可以检测HeLa细胞溶酶体中的Hg2+。 相似文献