全文获取类型
收费全文 | 2027篇 |
免费 | 11篇 |
国内免费 | 2篇 |
专业分类
化学 | 1046篇 |
晶体学 | 23篇 |
力学 | 52篇 |
数学 | 182篇 |
物理学 | 737篇 |
出版年
2021年 | 40篇 |
2020年 | 26篇 |
2019年 | 39篇 |
2018年 | 43篇 |
2017年 | 51篇 |
2016年 | 70篇 |
2015年 | 28篇 |
2014年 | 48篇 |
2013年 | 82篇 |
2012年 | 68篇 |
2011年 | 91篇 |
2010年 | 80篇 |
2009年 | 74篇 |
2008年 | 86篇 |
2007年 | 78篇 |
2006年 | 64篇 |
2005年 | 61篇 |
2004年 | 55篇 |
2003年 | 48篇 |
2002年 | 56篇 |
2001年 | 43篇 |
2000年 | 40篇 |
1999年 | 38篇 |
1998年 | 20篇 |
1997年 | 27篇 |
1996年 | 22篇 |
1995年 | 19篇 |
1994年 | 26篇 |
1993年 | 20篇 |
1992年 | 31篇 |
1991年 | 21篇 |
1990年 | 26篇 |
1989年 | 22篇 |
1988年 | 23篇 |
1987年 | 29篇 |
1986年 | 21篇 |
1983年 | 20篇 |
1982年 | 21篇 |
1980年 | 21篇 |
1979年 | 18篇 |
1978年 | 36篇 |
1977年 | 22篇 |
1976年 | 18篇 |
1975年 | 24篇 |
1974年 | 26篇 |
1973年 | 21篇 |
1972年 | 18篇 |
1971年 | 18篇 |
1968年 | 20篇 |
1967年 | 18篇 |
排序方式: 共有2040条查询结果,搜索用时 15 毫秒
41.
G.Z. Suleimanov V.V. Bashilov A.A. Musaev V.I. Sokolov O.A. Reutov 《Journal of organometallic chemistry》1980,202(2):C61-C63
The molecular structures of the L-menthyl ester of S-α-bromomercuriphenyl-acetic acid, diastereomer II, [α]20D ?18°, and of the related L-menthyl ester of α-bromobis(triphenylphosphine)platinummeruriphenylacetic acid, VI, have been investigated by the X-ray method. Insertion of L2Pt carbenoid appears to occur into the HgBr bond in II and two phosphine ligands in the product VI occupy cis positions in a planar square around the platinum atom. The HgPt distance is 2.50 Å; there is intermolecular HgBr coordination in II, the distance being 3.23 Å. 相似文献
42.
Summary A study of the isotope exchange of the ethyl esters of -brommercuryarylacetic acids with203Hg Br2 and 70% aqueous dioxane at 60°, made it possible to arrange the substituents in the following series in order of decreasing reaction rate: p-I, Br, Cl > p-F >H > o-CH3 > p-CH3> p-typet. C4H9. 相似文献
43.
44.
Elena V Chubarova Denis G. Samsonenko Maxim N. Sokolov Olga A. Gerasko Vladimir P. Fedin Javier G. Platas 《Journal of inclusion phenomena and macrocyclic chemistry》2004,48(1-2):31-35
A new inclusion compound which is a supramolecular adduct of cucurbit[8]uril with two guest molecules of phenylphosphonic acid, PhP(O)(OH)2, included into the cavity as ``two guests in host'' is reported. The guests match both size and hydrophilicity/hydrophobicity requirements. Two phenyl groups of molecules of PhP(O)(OH)2 are directed toward the center of the large hydrophobic cavity whereas the PO(OH)2 groups are outward-looking and bound with each hydrophilic portal of cucurbit[8]uril by a short hydrogen bond. 相似文献
45.
O. N. Chechina S. V. Sokolov A. P. Tomilov 《Russian Journal of General Chemistry》2004,74(11):1714-1718
Carboxylic acids prepared from hexafluoropropene oxide CF3CF2CF2O[CF(CF3)CF2O]nCF (CF3)COOH [n = 0, 2,5-bis(trifluoromethyl)-3,6-dioxaperfluorononanoic acid; n = 1, 2,5,8- tris(trifluoromethyl)-3,6,9-trioxaperfluorododecanoic acid], according to voltammetric data, enter the Kolbe reaction both at the Pt anode and at anodes from carbon materials in H2O-CH3CN and CH3OH-CH3CN solutions. The critical potential appreciably depends both on the anode material and on the solvent composition. Favorable effect of pyridine additions in H2O-CH3CN solutions is due to replacement of water molecules from the electrical double layer. The sodium ions exert a negative effect on the Kolbe synthesis.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 11, 2004, pp. 1842–1846.Original Russian Text Copyright © 2004 by Chechina, Sokolov, Tomilov.This revised version was published online in April 2005 with a corrected cover date. 相似文献
46.
A. V. Sokolov A. A. Nikanorov E. M. Pliss E. T. Denisov 《Russian Chemical Bulletin》1985,34(4):705-708
Conclusions The rate constant of the reaction of peroxide radicals of acrylic and methacrylic esters of polyols with nonpolar cumene is not dependent on the number of ester groups, and with polar 2,4,6-tri-tert-butylphenol decreases with an increase in the number of ester groups in the peroxide radical. Both findings are in agreement with the model of a dipole-dipole interaction in reactions of polyfunctional compounds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 778–781, April, 1985. 相似文献
47.
48.
49.
50.