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41.
3,5-二氟苄基氯和邻氯基苄基氯在适当的溶剂中与锡粉反应,合成了三(3,5-二氟苄基)氯化锡(1)和四(邻氯苄基)锡(2),经X射线衍射方法测定了新化合物的晶体结构。化合物1属单斜晶系,空间群为C2/c,晶体学参数:a=1.858 33(11)nm,b=1.140 98(7)nm,c=2.690 06(16)nm,β=109.288(10)°,V=5.383 6(6)nm3,Z=8,Dc=1.532 g·cm~(-3),μ(Mo Kα)=13.61 cm~(-1),F(000)=2 480,R1=0.085 1,wR~2=0.168 1。化合物2属单斜晶系,空间群为P21/m,晶体学参数:a=0.585 54(5)nm,b=1.969 74(18)nm,c=0.857 86(8)nm,β=95.204 0(10)°,V=0.985 34(15)nm3,Z=2,Dc=1.805 g·cm~(-3),μ(Mo Kα)=14.91 cm-1,F(000)=524,R1=0.054 0,wR_2=0.163 9;中心锡原子为畸变四面体构型。对其结构进行量子化学从头计算,探讨了化合物的稳定性、分子轨道能量以及部分前沿分子轨道的组成特征。测定了化合物的热稳定性。  相似文献   
42.
吡啶-4-甲酸与(n-Bu)2SnO反应合成二(μ-氧)二(μ-羟基氧)桥联四[二(正丁基)锡]二(吡啶-4-甲酸酯),经元素分析、1H NMR、IR和X-射线衍射表征分子结构,该配合物晶体属单斜晶系,空间群P21/n,晶胞参数:a=1.306 5(3)nm,b=1.314 5(2)nm,c=1.660 8(3)nm,β=96.180(5)°,V=2.835 7(9)nm3,Z=4,Dc=1.454 g.cm-3,μ(Mo Kα)=1.784 mm-1,F(000)=1 248,R1=0.044 9,wR2=0.124 1(I2σ(I))和R1=0.088 7,wR2=0.175 6(对所有的衍射)。共收集15 802个衍射点,其中独立衍射点4 885个,可观察衍射(I2σ(I))点2 733个用于结构精修。中心Sn原子形成五配位畸变三角双锥构型,分子间通过N…H-O氢键作用形成二维网络结构。利用量子化学G98W软件,在Lanl2dz基组对配合物的稳定性、前沿分子轨道组成及能量进行研究。  相似文献   
43.
The dibutyltin 3,4-dimethoxybenzotate compound {[(3,4-(CH3O)2C6H3COO) Sn(Bu-n)2]2O}2 has been synthesized by the reaction of dibutyltin oxide with 3,4-dimethoxybenzoic acid. Its structure was determined by X-ray single-crystal diffraction. The crystal belongs to the triclinic system,space group P1 with a = 1.2003(2),b = 1.2821(3),c = 1.3666(3) nm,α = 80.50(3),β = 65.56(3),γ = 73.36(3)°,Z = 2,V = 1.8318(6) nm3,Dc = 1.530 Mg·m-3,μ(MoKa) = 1.413 mm-1,F(000) = 860,R = 0.0554 and wR = 0.1092. In the complex,each tin atom adopts a distorted tigonal bipyramidal structure,and the dimer structure is shaped by one Sn2O2 planar four-membered ring. The stabilities of the title complex,along with its orbital energies and composition characteristics of some frontier molecular orbitals have been investigated by means of quantum chemistry calculation methods.  相似文献   
44.
邻香草醛缩2-氨基4-硝基苯酚(H2L)分别与二丁基氧化锡、二苄基二氯化锡反应, 合成了二丁基锡Schiff碱配合物(1)和单苄基Schiff碱配合物(2)。配合物经元素分析、1H NMR、13C NMR、IR、UV-Vis表征, 并用X-射线单晶衍射测定了分子结构。研究了配体H2L及配合物1、2对癌细胞Hela、MCF7、HepG2、Colo205、NCI-H460的抑制活性, 结果表明配合物1对这5种癌细胞的抑制效果优于现有抗癌药物卡铂, 可作为抗癌药物的候选化合物。在Tris缓冲溶液中, 以EB做为荧光探针, 用荧光光谱法研究了配体H2L及配合物2与鲱鱼精DNA的相互作用, 结果表明配合物与DNA作用主要是由于Schiff碱配体协同效应所致。  相似文献   
45.
在乙醇-苯溶剂中,对碘苯甲酸分别与三苯基氢氧化锡、二丁基氧化锡反应,合成了2个有机锡对碘苯甲酸酯,Ph3Sn(p-IC6H4O2)(1)和{[n-Bu2Sn(p-I-C6H4O2)]2O}2(2)。经IR、1H NMR、元素分析和X射线单晶衍射对配合物进行了表征。配合物1属三斜晶系,空间群为P1,中心锡原子与苯基碳原子、羧基氧原子构成畸型四面体,并且分子间通过氢键和C-I…π共同作用形成二聚体结构;配合物2属单斜晶系,空间群为C2/c,配合物是以Sn2O2构成的平面四元环为中心的二聚体结构,并且分子间通过I…I共同作用形成了一维链状结构。热重分析表明,配合物1和2在230℃以下具有良好的热稳定性。配合物1、2对杂草刺苋(Amaranthus spinosus)、马齿苋(Portulaca oleracea)的抑制活性大于对农作物绿豆的影响,且配合物1的抑制活性高于配合物2的抑制活性,为刺苋、马齿苋除草剂研究提供了一种方法。  相似文献   
46.
Alternate conjugated copolymers consisting of phenylene or biphenylylene unit and linear carbons unit such as cumulene and polyyne were synthesized. The optical property of these polymers was investigated by UV–Vis and fluorescence spectroscopies. Among cumulene-type polymers, the polymer having allene moiety showed a unique hypsochromic shift and intense blue fluorescence in solution, while poly(phenylenebutadiynylene)s, typical of polyyne-type linear conjugated polymers, showed fluorescence in the region from blue-green to green in high efficiency besides thermotropic liquid crystalline property. Substituent effects of the polymers on optical property as well as the band structure were evaluated on the basis of Hammet parameters, which was utilized for designing of the polymers. The poly(arylenebutadiynylenes)s were applied in polymer LED. The devices consisting of ITO/PEDOT-PSS/emitting polymer/Ca/Al realized EL emissions in the region covering RGB colors.  相似文献   
47.
48.
《结构化学》2020,39(8):1483-1488
Two Cd(II) and Co(II)-based complexes formulated as [Cd(bimh)(L)]·2H_2O(1) and [Co(bimh)-(L)]·2H_2O(2)(bimh = 1,6-bis(imidazole-1-yl)hexane, H_2L = 4,4?-(methylenebis(oxy))dibenzoic acid) have been successfully prepared under hydrothermal conditions. Single-crystal X-ray diffraction analysis indicates that the two complexes are isostructural and crystallize in Pbca space group. The whole three-dimensional(3D) architecture is based on three-fold interpenetrated layers containing double helical chains. In addition, the IR, TG and photoluminescence properties were also investigated.  相似文献   
49.
Creating cavities in varying levels, from molecular containers to macroscopic materials of porosity, have long been motivated for biomimetic or practical applications. Herein, we report an assembly approach to multiresponsive supramolecular gels by integrating photochromic metal–organic cages as predefined building units into the supramolecular gel skeleton, providing a new approach to create cavities in gels. Formation of discrete O‐Pd2L4 cages is driven by coordination between Pd2+ and a photochromic dithienylethene bispyridine ligand (O‐PyFDTE). In the presence of suitable solvents (DMSO or MeCN/DMSO), the O‐Pd2L4 cage molecules aggregate to form nanoparticles, which are further interconnected through supramolecular interactions to form a three‐dimensional (3D) gel matrix to trap a large amount of solvent molecules. Light‐induced phase and structural transformations readily occur owing to the reversible photochromic open‐ring/closed‐ring isomeric conversion of the cage units upon UV/visible light radiation. Furthermore, such Pd2L4 cage‐based gels show multiple reversible gel–solution transitions when thermal‐, photo‐, or mechanical stimuli are applied. Such supramolecular gels consisting of porous molecules may be developed as a new type of porous materials with different features from porous solids.  相似文献   
50.
《中国化学快报》2023,34(6):107935
A facile and elegant method for synthesis of novel N–aryl phenothiazine derivatives from 2-phenylindolizines and phenothiazines through direct electrochemical oxidation has been developed. This approach was performed smoothly at room temperature without external oxidant and catalyst. Cyclic voltammetry and in situ FTIR techniques were applied to analyze the cross-coupling process of phenothiazines and 2-phenylindolizines, which helped to select the appropriate reaction potential. Under the optimized conditions, a broad range of substrates were well tolerated, affording the desired products in moderate to excellent isolated yields (up to 91%) with high regioselectivity. Meanwhile, a plausible mechanism involving a radical pathway has been proposed.  相似文献   
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