全文获取类型
收费全文 | 7831篇 |
免费 | 189篇 |
国内免费 | 17篇 |
专业分类
化学 | 5140篇 |
晶体学 | 105篇 |
力学 | 177篇 |
数学 | 1143篇 |
物理学 | 1472篇 |
出版年
2020年 | 82篇 |
2019年 | 65篇 |
2016年 | 130篇 |
2015年 | 134篇 |
2014年 | 129篇 |
2013年 | 277篇 |
2012年 | 252篇 |
2011年 | 344篇 |
2010年 | 206篇 |
2009年 | 210篇 |
2008年 | 260篇 |
2007年 | 251篇 |
2006年 | 288篇 |
2005年 | 253篇 |
2004年 | 278篇 |
2003年 | 221篇 |
2002年 | 215篇 |
2001年 | 141篇 |
2000年 | 157篇 |
1999年 | 122篇 |
1998年 | 98篇 |
1997年 | 112篇 |
1996年 | 128篇 |
1995年 | 116篇 |
1994年 | 111篇 |
1993年 | 115篇 |
1992年 | 124篇 |
1991年 | 97篇 |
1990年 | 90篇 |
1989年 | 100篇 |
1988年 | 112篇 |
1987年 | 96篇 |
1986年 | 110篇 |
1985年 | 107篇 |
1984年 | 111篇 |
1983年 | 109篇 |
1982年 | 98篇 |
1981年 | 140篇 |
1980年 | 125篇 |
1979年 | 123篇 |
1978年 | 146篇 |
1977年 | 103篇 |
1976年 | 115篇 |
1975年 | 85篇 |
1974年 | 86篇 |
1973年 | 98篇 |
1972年 | 63篇 |
1971年 | 63篇 |
1970年 | 62篇 |
1968年 | 51篇 |
排序方式: 共有8037条查询结果,搜索用时 31 毫秒
981.
982.
Brian E. Broderick Wim P. Cofino Rita Cornelis Kaj Heydorn William Horwitz David T. E. Hunt Robert C. Hutton Howard M. Kingston Herbert Muntau Renato Baudo Daria Rossi Jacobus G. van Raaphorst Tjip T. Lub Peter Schramel Frank T. Smyth David E. Wells Allan G. Kelly 《Mikrochimica acta》1991,104(1-6):523-542
The Euroanalysis VII conference in Vienna included a two-day session: Quality Assurance in Analytical Chemistry. The contributions comprised 15 lectures devoted to: intra-laboratory quality measures, inter-laboratory control, formal aspects and accreditation and implementation. The paper presents an overview of the main items developed by the contributors.A survey on the session on Quality Assurance in Analytical Chemistry of Euroanalysis VIIThe authors thank the organizers of EUROANALYSIS VII and in particular Dr. B. Griepink and Dr. E. Maier of the Community Bureau of Reference (BCR) of the CEC for their support and considerable contributions. 相似文献
983.
984.
985.
986.
The outer automorphism group of a nest algebra is canonically isomorphic to the (spatial) automorphism group of the nest itself. The outer automorphism group of the associated quasitriangular algebra is canonically isomorphic to a group of “approximate” automorphisms of the nest. A simple proof that every derivation of a quasitriangular algebra is inner is obtained as a corollary. 相似文献
987.
The steady propagation of a thin smouldering front in a half-spacehas been considered. A suitable coordinate transformation hasallowed the region near the leading edge of the front to beexamined for both a maintained planar surface and with surfacecollapse due to material shrinkage. The change in the oxidizerconcentration for a small increment in the propagation speedfor large time and surface collapse has been determined. Theinfluence of two types of nonlinear diffusion on the shape ofthe smouldering front has been found; other cases can be dealtwith in a similar manner. 相似文献
988.
Herbert Schneckenburger Michael H. Gschwend Wolfgang S. L. Strauss Reinhard Sailer Rudolf Steiner 《Journal of fluorescence》1997,7(1):3-10
Spectroscopic and microscopic methods for probing mitochondrial malfunction were established using cultivated endothelial
cells from the calf aorta and various inhibitors of the respiratory chain, which is located at the inner mitochondrial membrane.
Time-gated fluorescence spectroscopy was used to measure autofluorescence of the coenzyme NADH as well as “energy transfer
efficacy” from excited NADH molecules (energy donor) to the mitochondrial marker rhodamine-123 (energy acceptor). Autofluorescence
usually exhibited a weak increase after specific inhibition of enzyme complexes of the respiratory chain. In contrast, a pronounced
increase in energy transfer efficacy was observed after inhibition of the same enzyme complexes. The detection of donor (NADH)
and acceptor (R123) fluorescence in different nanosecond time gates following the exciting laser pulses enhances selectivity
and improves quantification of energy transfer measurements. Therefore, timegated energy transfer spectroscopy is suggested
to be an appropriate tool for probing mitochondrial malfunction. 相似文献
989.
Herbert Tausend und Willy Niclaus 《Fresenius' Journal of Analytical Chemistry》1969,245(5):293-295
Zusammenfassung Tyramin wurde mit 4-Nitro-azobenzolcarbonsäure-(4)-chlorid umgesetzt. Es entstehen in Abhängigkeit von den Versuchsbedingungen das N-Acylbzw. das N,O-Diacylderivat. Die N-Acylierung verläuft praktisch quantitativ und kann zur photometrischen Bestimmung der Base herangezogen werden.
On the reaction of tyramine with 4-nitroazobenzene-(4)-carboxylic acid chloride and its photometric determination
Tyramine was allowed to react with the reagent under different conditions. N-acyl- and N,O-diacyl derivatives were formed respectively. A quantitative determination of the base could be achieved by photometric measurement of the N-acyl compound.相似文献
990.