全文获取类型
收费全文 | 8636篇 |
免费 | 21篇 |
国内免费 | 3篇 |
专业分类
化学 | 5403篇 |
晶体学 | 116篇 |
力学 | 282篇 |
数学 | 1135篇 |
物理学 | 1724篇 |
出版年
2019年 | 98篇 |
2018年 | 163篇 |
2017年 | 162篇 |
2016年 | 194篇 |
2015年 | 80篇 |
2014年 | 195篇 |
2013年 | 233篇 |
2012年 | 238篇 |
2011年 | 242篇 |
2010年 | 242篇 |
2009年 | 223篇 |
2008年 | 221篇 |
2007年 | 219篇 |
2006年 | 166篇 |
2005年 | 147篇 |
2004年 | 145篇 |
2003年 | 145篇 |
2002年 | 153篇 |
2001年 | 116篇 |
2000年 | 83篇 |
1998年 | 110篇 |
1997年 | 108篇 |
1995年 | 112篇 |
1994年 | 105篇 |
1993年 | 105篇 |
1992年 | 118篇 |
1991年 | 132篇 |
1990年 | 122篇 |
1989年 | 123篇 |
1988年 | 118篇 |
1987年 | 147篇 |
1986年 | 154篇 |
1985年 | 135篇 |
1984年 | 129篇 |
1983年 | 142篇 |
1982年 | 137篇 |
1981年 | 136篇 |
1980年 | 129篇 |
1979年 | 160篇 |
1978年 | 192篇 |
1977年 | 247篇 |
1976年 | 273篇 |
1975年 | 192篇 |
1974年 | 188篇 |
1973年 | 193篇 |
1972年 | 189篇 |
1971年 | 150篇 |
1970年 | 129篇 |
1969年 | 110篇 |
1968年 | 119篇 |
排序方式: 共有8660条查询结果,搜索用时 15 毫秒
1.
2.
V. A. Samsonov L. B. Volodarskii V. L. Korolev G. Kh. Khisamutdinov 《Chemistry of Heterocyclic Compounds》1994,30(10):1243-1249
The reaction of 4-aminobenzofurazan with aryldiazonium salts leads to the formation of 4-amino-5-aryl-azobenzofurazans and 5-amino-2-aryl-4-nitroso-2H-benzotriazoles, products of the rearrangement of the initially formed 4-amino-7-(arylazo)benzofurazans. Oxidation of the benzofurazan as well as of the triazole derivatives gives 7-aryl-1,2,3-triazol[4,5-e]benzofurazans. The chemical properties of some of the compounds obtained have been investigated.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1432–1438, October, 1994. Original article submitted July 25, 1994. 相似文献
3.
By changing the conditions of the electrohydraulic treatment of aqueous plant heterodisperse systems comparatively high degradation
of the lignin component of plant tissue has been achieved. In addition to free monosaccharides, their reduced forms have been
detected in the aqueous phase.
Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89
14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 795–798, November–December, 1994. 相似文献
4.
D. Kh. Khalikov M. G. Mukhiddinov M. G. Asoev V. A. Degtyarev 《Chemistry of Natural Compounds》1994,30(6):734-738
Some features of the kinetics of the hydrolysis of apple protopectin have been studied on the basis of an analysis of monosaccharide residues of the pectin substances and determinations of characteristic viscosity. It has been shown that the fine regulation of the physicochemical parameters of the hydrolysis of protopectin leads to the formation of pectin substances with different properties. 相似文献
5.
Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 891475.
Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 679–680, September–October, 1994. 相似文献
6.
7.
The present paper analyzes the properties of structural phase transitions under the extremal conditions of high pressures. In the context of the theory of density functional (TDF), the pressures of the B1–B2 transitions are calculated for small alkali-halide crystals as functions of the crystal size. The size effect of the B1–B2 transition – an increase in the transition pressure with the decreasing crystal grain radius – has been established for all investigated halides except lithium fluoride for which the dependence is reverse. 相似文献
8.
M. Kh. Azamkhuzhaev 《Computational Mathematics and Modeling》1991,2(4):406-411
Translated from Programmnoe Oborudovanie i Voprosy Prinyatiya Reshenii, pp. 210–219, 1989. 相似文献
9.
10.
L. Ya. Yukel'son I. I. Parilis G. L. Bussel' D. Kh. Khamidov 《Chemistry of Natural Compounds》1989,25(6):698-704
On the basis of a computer analysis of four classes of toxic polypeptides, generalized primary structures of each class have been obtained which can be used for planning the synthesis of biologically active compounds. 相似文献