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101.
102.
具有纳米孔洞的金属-有机超分子聚合物与功能材料 总被引:5,自引:0,他引:5
本文介绍了近几年来一个热门的研究领域-纳米超分子笼和具有纳米孔洞的金属-有机聚合物的研究现状和发展趋势。目前该领域的研究主要集中在:设计合成有机桥联配体并与金属离子自组装成各类具有纳米孔洞的超分子化合物和一维、二维或三维的金属-有机聚合物,应用结构化学研究手段,研究它们的自组装规律、空间结构、电子结构及其物理化学性能,寻找这两类化合物在生物工程与功能材料等领域中的应用。 相似文献
103.
本文介绍了近几年来一个热门的研究领域-纳米超分子笼和具有纳米孔洞的金属-有机聚合物的研究现状和发展趋势。目前该领域的研究主要集中在:设计合成有机桥联配体并与金属离子自组装成各类具有纳米孔洞的超分子化合物和一维、二维或三维的金属-有机聚合物,应用结构化学研究手段,研究它们的自组装规律、空间结构、电子结构及其物理化学性能,寻找这两类化合物在生物工程与功能材料等领域中的应用。 相似文献
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105.
A new asymmetric oligobipyridine ligand, 1-(5'-methyl-2, 2'-bipyridin-5-yl)-2-(6'-methyl-2, 2'-bipyridin-6-yl)ethane (L), in which the bipyridine units are bridged by CH_2CH_2 at 5, 6'-position has been synthesized. The ligand L reacts with Cu(Ⅰ) and Cu(Ⅱ) ions giving double-stranded helical complexes [Cu_2~ⅠL_2] (ClO_4)_2·Et_2O (1) and [Cu_2~ⅡL_2 (OH) (H_2O)][ClO_4]_3(2), respectively. Complexes 1 and 2 were characterized by X-ray diffraction analyses, ES-MS, ESR and cyclic voltammetry, etc. Differing from the oligobipyridine ligands bridged by CH_2CH_2 at 6,6'-or 5,5'-position, the ligand L not only forms a double-stranded helicate with Cu(Ⅰ) ion, but also gives a double-stranded helicate with Cu(Ⅱ) ion. The results show that the linkage mode of the spacer group to the bipyridine units exerts a great impact on the formation of helix. 相似文献
106.
107.
Keiji Hirose 《Journal of inclusion phenomena and macrocyclic chemistry》2001,39(3-4):193-209
When working in the field ofhost–guest chemistry, the binding constants have to bedetermined on many occasions. Here is a detaileddocument of how to determine the binding constantswhich covers both the basic principle and thepractical issue: a practical experimental guideline,a representative method for the determination ofstoichiometry and for the evaluation of a complexconcentration, precautions to be taken on setting upconcentration conditions of the titration experiment,practical data-treatment methods and estimation ofstatistical errors. This document is described indetail using the basic level of mathematics,statistics, and programs of spreadsheet software.Especially, the titration experiments by means ofUV-visible and NMR spectroscopy are carried out anddescribed. 相似文献
108.
Sanjeev Goswami Vivek K. Gupta D. I. Brahmbhatt U. R. Pandya 《Journal of chemical crystallography》2007,37(3):213-217
3-(2,4-Dimethylphenyloxymethyl)-3,4-dihydroisocoumarin (C18H18O3) was prepared by the alkylation of o-lithio N-methyl benzamide with 2-(2,4-dimethylphenoxy)methyl oxirane, followed by alkaline hydrolysis. The compound crystallizes in the orthorhombic space group Pbca with unit cell parameters : a = 8.239(2) Å, b = 14.918(5) Å, c = 24.831(9) Å, Z = 8. The crystal structure was solved by direct methods and refined to R = 0.0514 for 1564 observed reflections. The heterocyclic ring adopts a distorted half-chair conformation. Molecules are connected by π–π interactions between phenyl rings of the isocoumarin nucleus forming dimers. Dimers are connected via C–H...O hydrogen bonds forming chains. Further intermolecular C–H...π hydrogen bonds link the dimer chains to form supramolecular structure. 相似文献
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110.
A new dinuclear centrosymmetric complex [LaL(HL)(H2O)3]2(2H2O (H2L = 3-nitrophthalic acid, NPA) was synthesized in water/ethanol solution and characterized by X-ray diffraction, IR spectrum and TGA-DTA. The complex crystallizes in triclinic system, space group P-1 with a = 8.1549(16), b = 8.8856(18), c = 15.277(3)(A),α= 100.93(3),α= 90.81(3), γ= 104.56(3)°, V = 1049.8(4)(A)3, Z = 1,μ= 2.125 mm-1, Dc=1.994 g/cm3, R = 0.0259 and wR = 0.0679. Two 3-nitrophthalates(2-) coordinate with the La3 ions in a bridging mode, and two monohydrogen- 3-nitrophthates(1-) and three waters in terminal ways, respectively. Each La3 ion is nine-coordinated to exhibit a distorted tricapped trigonal prism coordination polyhedron. Both the coordinated and crystal waters are involved in the inter- and intramolecular hydrogen bonds. The dinuclear units are linked into a 2D network structure in the ab plane via intermolecular hydrogen bonds along the axes a and b. Two crystal waters fill each rhombic pore of the network. The networks are further packed along the c axis forming a layered supramolecular structure through the C-H…O weak forces between the adjacent sheets. TGA analysis shows the complex undergoes the loss of waters of crystallization and coordination and the decomposition of ligands sequentially. 相似文献