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71.
The reaction of triphenyl phosphite ozonide with various types of diazo compounds results in their oxidation, which is accomplished by singlet oxygen (1O2) evolved during thermal decomposition of the ozonide. A decrease in the ionization potential of the substrate results in an increase in the overall rate constant of quenching of1O2. In the case of 9-diazofluorene, the main channel of1O2 quenching is physical quenching.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1567–1571, September, 1994.The work was carried out with the financial support of the Russian Foundation for Basic Research (Project No. 93-03-5231).  相似文献   
72.
Abstract

A three-component reaction between barbituric/thiobarbituric acid, phosphines, and dialkyl acetylenedicarboxylates in dry acetonitrile led to the formation of barbiturate/thiobarbiturate-functionalized stable zwitterionic salts in a one-pot process. When trialkyl phosphites were used instead of phosphines, barbiturate/thiobarbiturate-functionalized phosphonates were obtained in good yields.  相似文献   
73.
A new vanadium(III) phosphite, (C4H8N2H4)0.5(C4H8N2H3)[V4(HPO3)7(H2O)3]1.5H2O, has been synthesized hydrothermally by using V2O5, H3PO3 as reactants, piperazine as the structure-directing agent. The as-synthesized product was characterized by powder X-ray diffraction, IR spectroscopy, inductively coupled plasma analysis, thermogravimetric analysis, and SQUID magnetometer. Single-crystal X-ray diffraction analysis shows that the title compound crystallized in the trigonal space group (No. 165) with the parameters: , , and Z=4. Its structure is built up by alternation of octahedral VO6 or VO5(H2O) and pseudo-pyramidal HPO3 units to form infinite 2D layers, and these layers are interconnected by sharing vertex-oxygen with octahedral VO6 units to generate a 3D open-framework structure with 12-membered ring channels in a and b directions, respectively, where there exist entrapped diprotonated and mono-protonated piperazine cations, and water molecules. Magnetic measurement indicates that paramagnetic behavior is observed down to 4 K.  相似文献   
74.
气相色谱法测定农药中间体亚磷酸三甲酯及邻二氯苯的含量李来生(南昌大学应用化学研究所南昌330047)关键词亚磷酸三甲酯农药中间体气相色谱法合成中图分类号O657.71亚磷酸三甲酯作为一种重要的有机合成中间体,被广泛用于合成敌敌畏等多种农药和难燃剂[1...  相似文献   
75.
迄今,在中温水热条件下已合成了大量具有空旷骨架结构的过渡金属磷酸盐微孔材料[1],这类材料在非线性光学材料、磁性材料、超导材料及催化等诸多方面具有潜在的应用前景[2~5].自从第一个以有机胺为模板的磷钒氧化合物[(CH3)2NH2]K4[V10O10(H2O)2(OH)4(PO4)7]·4H2O[6]的合成以来,又有几十种结构的磷钒氧化合物被报道.但以亚磷酸为结构基元构筑的磷钒氧化合物的报道较少.1995年,Zubieta等[7]报道了以哌嗪为模板剂的两个亚磷酸钒化合物[HN(Me)(CH2CH2)2N·(Me)H][(VO)4(OH)2(HPO3)4]和[H2N(CH2CH2)2NH2][(VO)3(HPO3)4(H2O…  相似文献   
76.
首次合成了标题化合物C2 0 H2 3 N14 O7PS ,并通过元素分析、IR和1HNMR对化合物进行了表征 ,用X射线单晶衍射法测定了该化合物的晶体结构。晶体中一个不对称单元内有四个结晶学上独立的分子 ,这四个分子的构型基本相同。每两个分子之间以一对N—H…O氢键连接 ,生成一个非中心对称的二聚体 ,组成二聚体的两个分子侧链局部构象存在明显的差异。整个晶体则是由这些二聚体以vanderWaals作用力堆积而成。  相似文献   
77.
Synthesis of new aminomethylphosphonic acids containing benzo-15-crown-5 ether, is described. These compounds were obtained from the 4′-formylbenzo-15-crown-5 by a sequence of reactions, which afforded 4′-(aminomethylphosphono)-benzo-15-crown-5 and its N-benzyl derivative in high yields.  相似文献   
78.
Six organophosphine/phosphite stabilized silver(I) complexes of 2-acetyl-1,3-indandione (2-AID) of type Ln·AgC11H7O3 (L = PPh3; n = 1, 2a; n = 2, 2b; L = P(OMe)3; n = 1, 2c; n = 2, 2d; L = P(OEt)3; n = 1, 2e; n = 2, 2f) have been prepared by reacting of [AgC11H7O3], which could be obtained by reacting of 2-AID with AgNO3, with triphenylphosphine, trimethylphosphite, or triethylphosphite in 1:1–2 M ratio. These complexes were obtained in high yields and characterized by elemental analysis, 1H, 13C{H} NMR, IR spectroscopy, and thermal analysis (TG and DSC), respectively. The molecular structure of 2a has been determined by X-ray single crystal analysis in which the silver atom is in a distorted trigonal geometry.  相似文献   
79.
A new three-dimensional (3-D) zinc phosphite with Zn/P ratio of 4/5, [Ni(C6N2H14)2][Zn4(H2O)(HPO3)5] (1), has been prepared by using self-assembled nickel complexes as the structure-directing agents. Its structure is built up from strict alternation of ZnO4 tetrahedra and HPO3 pseudo-pyramids, resulting in an open framework with multi-directional intersecting 8-, 12- and 16-ring channels. The unique nickel complexes Ni(DACH)2 (DACH=1,2-diaminocyclohexane) only involving the cis-DACH acting as ligands are self-assembled under hydrothermal conditions, and act as the structure-directing agents (SDAs) to direct the formation of compound 1. Nickel complexes reside in the channels in a manner that the hydrophobic ends of the cis-DACH molecules exclusively protrude into the 16-ring pores and the amino groups closely interact with the charged inorganic framework through weak H-bonds. The interesting arrangements of nickel complexes imply a feasible approach to the design and synthesis of extra-large pore materials.  相似文献   
80.
To better understand the effects of ligand configuration on hydroformylation reactions carried out in the presence of LiBPh4·3dme (dme = 1,2-dimethoxyethane), a conformationally restrained bis(phosphite) ligand derived from 1,2-bis-(2-hydroxyethoxy)benzene, {[(2,2′-O2C12H8)P(C2H4O2)]2C6H4}, 1, has been prepared and its Rh(I) metallacrown ether complex has been evaluated as a catalyst for the hydroformylation of styrene. Both the activity and regioselectivity of the catalyst are sensitive to the amount of the LiBPh4·3dme added with the activity decreasing by 16% and the regioselectivity for the iso increasing by 9% at a 8:1 LiBPh4:Rh ratio.Model complexes for the octahedral, cis-Mo(CO)4(1), 2, and square planar, cis-PtCl2(1), 3, and cis-PdCl2(1), 4, complexes in the catalytic cycle has been have been studied using multinuclear NMR spectroscopy and X-ray crystallography. Although the X-ray crystal structure of 2 suggests that the metallacrown ether ring could adopt a configuration capable of binding alkali metal cations, this does not appear to occur in a dichloromethane-d2 solution of 2 because no shift in the 31P NMR resonance 2 is observed upon the addition of an excess of LiBPh4·3dme. The 31P{1H} NMR spectra of chloroform-d solutions of 2 (in the presence of a catalytic amount of HgCl2) and of 4 and the X-ray crystal structures of the complexes indicate that the bis(phosphite) ligands are cis coordinated in these complexes in both the solution and in the solid state. This is particularly surprising for 4 because related PdCl2{Ph2P(CH2CH2O)nCH2CH2PPh2} (n = 3-5) complexes exhibit both cis-trans and monomer-oligomer equilibria in solution.  相似文献   
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