全文获取类型
收费全文 | 1368篇 |
免费 | 28篇 |
国内免费 | 9篇 |
专业分类
化学 | 721篇 |
晶体学 | 3篇 |
力学 | 34篇 |
数学 | 362篇 |
物理学 | 285篇 |
出版年
2023年 | 7篇 |
2022年 | 18篇 |
2021年 | 13篇 |
2020年 | 19篇 |
2019年 | 26篇 |
2018年 | 28篇 |
2017年 | 26篇 |
2016年 | 37篇 |
2015年 | 37篇 |
2014年 | 35篇 |
2013年 | 97篇 |
2012年 | 106篇 |
2011年 | 75篇 |
2010年 | 44篇 |
2009年 | 46篇 |
2008年 | 84篇 |
2007年 | 72篇 |
2006年 | 68篇 |
2005年 | 66篇 |
2004年 | 70篇 |
2003年 | 51篇 |
2002年 | 31篇 |
2001年 | 32篇 |
2000年 | 31篇 |
1999年 | 29篇 |
1998年 | 9篇 |
1997年 | 11篇 |
1996年 | 9篇 |
1995年 | 16篇 |
1994年 | 13篇 |
1993年 | 13篇 |
1992年 | 14篇 |
1991年 | 9篇 |
1990年 | 8篇 |
1989年 | 5篇 |
1988年 | 6篇 |
1985年 | 11篇 |
1984年 | 10篇 |
1983年 | 6篇 |
1982年 | 13篇 |
1981年 | 12篇 |
1980年 | 5篇 |
1979年 | 8篇 |
1978年 | 9篇 |
1977年 | 10篇 |
1976年 | 10篇 |
1975年 | 9篇 |
1974年 | 13篇 |
1973年 | 6篇 |
1960年 | 3篇 |
排序方式: 共有1405条查询结果,搜索用时 16 毫秒
1.
Kavitha Telikepalli Király Tamás Matuschke Jannik Schlotter Ildikó Schmidt-Kraepelin Ulrike 《Mathematical Programming》2022,192(1-2):567-595
Mathematical Programming - Let G be a digraph where every node has preferences over its incoming edges. The preferences of a node extend naturally to preferences over branchings, i.e., directed... 相似文献
2.
Huan Yang Ying Zhou Pingtian Yu Yaya Yang Zhaoqun Jiao James P. Tam 《Natural product research》2019,33(9):1251-1256
A novel PCR technology was developed to detect short DNA fragments using species-specific primers for rapid and non-sequencing authentication of Bombyx batryticatus based on differences in the mitochondrial genome. Three specifically designed primer reactions were established to target species for the reliable identification of their commercial products. They were confirmed to have a high inter-species specificity and intra-species stability. The limit of detection was estimated as 1 ng of genomes for Beauveria bassiana and 100 pg for Bombyx mori and Metarhizium anisopliae. Furthermore, validation results demonstrated that raw materials and their processed products can be conveniently authenticated with good sensitivity and precision using this newly proposed approach. In particular, when counterfeits were assayed, these primer sets performed well, whereas COI barcoding technology did not. These could also assist in the discrimination and identification of adulterates of other animal-derived medicines in their pulverized and processed forms and even in complexes. 相似文献
3.
The minor relation of functions is generalized to multisorted functions. Pippenger’s Galois theory for minor-closed sets of functions is extended to multisorted functions and multisorted relation pairs. Reflections of minor-closed sets are again minor-closed, and the effect of reflections on the invariant relation pairs of minor-closed sets of multisorted functions is described. 相似文献
4.
Nguyen Van Hung Vo Minh Tam Dumitru Baleanu 《Mathematical Methods in the Applied Sciences》2020,43(7):4614-4626
In this paper, we consider a class of split mixed vector quasivariational inequality problems in real Hilbert spaces and establish new gap functions by using the method of the nonlinear scalarization function. Further, we obtain some error bounds for the underlying split mixed vector quasivariational inequality problems in terms of regularized gap functions. Finally, we give some examples to illustrate our results. The results obtained in this paper are new. 相似文献
5.
Structural Characterization of O‐ and C‐Glycosylating Variants of the Landomycin Glycosyltransferase LanGT2 下载免费PDF全文
Dr. Heng Keat Tam Dr. Johannes Härle Dr. Stefan Gerhardt Prof. Dr. Jürgen Rohr Guojun Wang Prof. Dr. Jon S. Thorson Dr. Aurélien Bigot Monika Lutterbeck Dr. Wolfgang Seiche Prof. Dr. Bernhard Breit Prof. Dr. Andreas Bechthold Prof. Dr. Oliver Einsle 《Angewandte Chemie (International ed. in English)》2015,54(9):2811-2815
The structures of the O‐glycosyltransferase LanGT2 and the engineered, C? C bond‐forming variant LanGT2S8Ac show how the replacement of a single loop can change the functionality of the enzyme. Crystal structures of the enzymes in complex with a nonhydrolyzable nucleotide‐sugar analogue revealed that there is a conformational transition to create the binding sites for the aglycon substrate. This induced‐fit transition was explored by molecular docking experiments with various aglycon substrates. 相似文献
6.
Zsolt Zsótér Tibor Tímár Krisztina Kónya Tamás Patonay József Jekő 《Journal of heterocyclic chemistry》2015,52(6):1677-1683
4,4‐Dimethylchromeno[4,3‐d]selenadiazoles 8 with insecticide activities have been synthesized via oxidative ring closure of the corresponding semicarbazone derivatives 7 by treatment with selenium dioxide. Reaction of various alkoxy‐2,2‐dimethyl‐2H‐benzopyrans with phenylselenyl chloride was utilized to prepare different phenylselenyl‐ and 3‐chloro precocene analogs. 相似文献
7.
8.
9.
10.