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61.
以R-联萘酚、氯氰胺、间苯二胺、1,2二苯基乙二胺、乙二胺为原料合成了3个水溶性手性大环荧光传感器;利用核磁共振(1 H NMR和13 C NMR)、质谱、红外光谱验证了合成产物的结构,利用元素分析仪测定了其组成,并利用X射线衍射分析确定了单晶R-3的晶体结构.结果表明,R-3属于单斜晶系,P2(1)/n空间群,晶胞参数为:a=1.128 6nm,b=1.566 1nm,c=2.293 9nm,β=90°,Z=4,Dc=1.328g.cm-3,F(000)=1 684.  相似文献   
62.
Abstract

Four polyammonium macrocycles were synthesized and characterized: two with 21-membered rings and differing numbers of oxygen and nitrogen heteroatoms, [21]N6O (1) and [21]N5O2 (2), and two with bipyridine incorporated into the ring, [24]N4O2bipy (3) and [27]N3O2bipy (4). Their ability to catalyze the dephosphorylation of adenosine triphosphate was examined. It was found that ring size plays a crucial role in the catalytic ability of the macrocycles, with the 21-membered rings being superior to larger macrocycles. Also, rates of dephosphorylation were found to increase with increasing number of nitrogen atoms in the ring. For two of the macrocycles, crystal structures were determined. Macrocycle 2 crystallizes in the tricliriic space group PI, a = 10.692(1), b = 17.037(2), c = 8.1952(8)Å, a = 92.550(9), β = 100.816(9), γ = 106.77(1)°, V = 1396.1(3) Å3; the structure was solved to R = 0.089 and R w = 0.098. Macrocycle 4 crystallizes in the monoclinic space group P21/n, a = 14.589(1), b = 15.427(1), c = 16.382(1) Å, b = 90.137(6)°, V = 3687.0(9) Å3; the structure was solved to R = 0.056 and R w = 0.085.  相似文献   
63.
The syntheses of mixed oxygen-nitrogen donor macrocycles incorporating two or three pendant carboxylic acid groups are described. Potentiometric titrations in water (I = 0.1; KNO3) at 25°C have been used to determine the stability constants for the 1: 1 (metal:ligand) complexes of Co(II). Ni(II), Cu(II), Zn(II), and Cd(II). The constants obtained are compared with the previously determined values for the corresponding complexes of the unsubstituted macrocyclic precursors. The results of these studies indicate that each carboxylate function participates in binding to the central metal. For some metal-ion/ligand systems there is evidence that ring size effects influence the overall stability patterns and that, in such cases, both the ether oxygens as well as the tertiary amines of the macrocyclic rings appear to bind to the metal.  相似文献   
64.
Two new polyoxometalate-templated supramolecular compounds, [CuI4(bpmb)4][PMoVI11MoVO40] (1) and [CuI4(bpmb)4SiW12O40] (2) (bpmb = 1,4-bis(pyrazol-1-ylmethyl)benzene), have been synthesized under hydrothermal conditions and characterized by routine methods. Structural analysis shows that in 1, there exist crown-like [CuI4(bpmb)4] coordination macrocycles, and the Keggin polyanions [PMo VI11MoVO40]4? (abbr. as PMo12), which direct the crown-like macrocycle to form a 3-D supramolecular framework. In 2, there exist unusual meso-helix chains, and these chains are mutually interlaced in a wave–trough pattern, but without intersection resulting in a multi-cavity layer, in which the [SiW12O40]4? (abbr. as SiW12) clusters as guest molecules occupy the cavities of the layers. The distinct structural features of the two compounds suggest that Keggin polyanions should play a significant role in the process of assembly. Electrocatalytic properties of 1 and 2 were investigated.  相似文献   
65.
Inclusion studies for metal-organic open-frameworks, [Ni(C10}H24N4)(H2O)2]3[BTC]2·24H2O (1) and [Ni(C10H26N6)]3 [BTC]2·18H2O(2) (BTC3- = 1,3,5-benzenetricarboxylate) with various organic andinorganic guest molecules have been carried out. 1 is the previously reportedmolecular floral lace with 1-D channels, where positively charged macrocyclic layersand negatively charged BTC3- layers are alternately packed by hydrogen bondinginteractions. 2 is assembled in this study from nickel(II) hexaazamacrocyclic complexcontaining methyl pendant arms and BTC3-. The X-ray structure of 2 shows thatthe nickel(II) complex and BTC3- form a 2-D coordination polymer. The XRPD patternsof 2 indicate that framework of 2 is slightly deformed upon removal of waterguest molecules but restored upon rebinding of water. The host solid 1 binds MeOHin toluene, and 1,3,5-trihydroxybenzene (THB) and 4-hydroxyacetophenone (HAP) in EtOH/toluene (v/v = 1/4) solutions. The binding constants (Kf) of 1 forMeOH, THB, and HAP are 66.4 M-1, 259 M-1, and 13.9 M-1,respectively. In the range of high concentration of the guest, however, the host showsvarious binding curves depending upon the types of guest. It binds PhOH in toluene,showing a sigmoid curve. It also binds transition metal complexes such as[Cu(NH3)4](ClO4)2, [Cu(ethylenediamine)2](ClO4)2,[Cu(histamine)2](ClO4)2, and[Cu(N,N'-bis(3-aminopropyl)ethylenediamine)](ClO4)2 in MeCN, with Kf values of 645 M-1, 9.52 M-1, 37.2 M-1, and 6.00 M-1,respectively. The host solid 2 binds selectively PhOH over PhCl and PhBr, showing that hydrogen bonding interaction between the host and guest plays an important role in the selectivity.  相似文献   
66.
单N-乙酸取代O2N2大环配体及其稀土配合物的合成与表征   总被引:2,自引:0,他引:2  
Aseries of new rare earth complexes LnL(NO3)2·2H2O(Ln=La,Pr,Nd,Sm,Eu,Gd,Dy,Yb;L=1,2-diaza-3,4: 9,10-dibenzo-5,8-dioxyacyclopentadecane-N-acetic ion) were prepared. The complexes were characterized by elemental analysis, ICPmethod, IRspectra, 1H NMRand Molar conductance. It was found that the ether oxygen, carboxy oxygen and nitrogen atoms of the ligand are coordinated to the metal ion, as well as a free nitrate and coordianted nitrate ion in the complex.  相似文献   
67.
Abstract The novel ionic compound [H2bdtd][CoCl4] · 2H2O (1) was prepared by the reaction between CoCl2 and 2,13-bis(acetamido)-3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.18,07.12]docosane (bdtd) in adjusted to pH 3.0 by 1.0 M HCl and structurally characterized. The crystals are monoclinic C2/c with a = 18.7777(9), b = 9.7356(4), c = 20.0884(9) ?, β = 109.6340(10)°, V = 3458.9(3) ?3, Z = 4. The dication H2bdtd occupies a special position about an inversion center. The cobalt(II) atom in the anion is in a distorted tetrahedral environment with four chloride ligands. The crystal structure is stabilized by a variety of hydrogen-bonding contacts involving the dication, chloride anions and solvent water molecules. Cyclic voltammetry of [CoCl4]2− anion in 1 undergoes irreversible one-electron reduction to the CoII/CoI. Graphical abstract The crystal structure of the ionic compound [H2bdtd][CoCl4] · 2H2O (1) consists of [H2bdtd]2+ cation, [CoCl4]2− anion and water molecules joined together by ionic interaction and hydrogen bonds. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
68.
1 INTRODUCTION Polyaza-macrocyclic compounds with functional substituents have been extensively investigated recen- tly because of their potential applications in radioac- tive therapy, recovery of metal ions, biomimetic che- mistry, and catalysis[1, 2]. With various structures and distinctive properties, they have become significant building blocks for further chemical studies[3~6]. As far as the preparation method is concerned, metal template condensation reactions are shown to be effec…  相似文献   
69.
大环分子如环糊精、冠醚等因具备独特的空腔结构, 能够通过主-客体相互作用实现对分子、离子的特异性识别, 因此常被应用于人工跨膜离子传输系统的研究和开发. 与天然的通道蛋白相比, 大环分子具有价格低廉、性质稳定、结构易于修饰和功能化等诸多优点, 因而备受科研工作者们的关注. 本综述详细介绍了大环分子在人工离子通道领域中的研究进展, 按照不同的大环分子进行分类, 系统归纳了基于大环结构的人工跨膜通道的制备方法、结构调控以及其在生物医药领域中的潜在应用. 最后对大环类人工离子通道做了简要的总结和展望, 该综述对于发展新型人工离子通道以及发掘其潜在的应用价值具有重要意义.  相似文献   
70.
The photoreduction behavior of p-nitroaniline (pNA) in the presence of N,N-dimethylaniline (DMA) induced by both steady-state (365 nm) and laser (337 nm) irradiation has been analyzed. The stoichiometry of the photoreduction reaction revealed that several amino radicals derived from DMA were generated by each photoreduced pNA molecule. The polymerization kinetics of the lauryl acrylate monomer (LA) photoinitiated by the pNA/DMA system has been studied by differential scanning photocalorimetry (Photo-DSC). The rate of polymerization was found to be proportional to the square root of both the incident light and the coinitiator DMA concentration. The order of the polymerization reaction with respect to monomer and initiator concentration was determined, as well as the polymerization behavior under aerobic conditions. The polymerization efficiency of this photoinitiated system was much higher than that obtained with conventional aromatic ketone photoinitiators. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3801–3812, 1997  相似文献   
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