全文获取类型
收费全文 | 1085篇 |
免费 | 46篇 |
国内免费 | 4篇 |
专业分类
化学 | 773篇 |
晶体学 | 20篇 |
力学 | 32篇 |
数学 | 76篇 |
物理学 | 234篇 |
出版年
2024年 | 7篇 |
2023年 | 15篇 |
2022年 | 20篇 |
2021年 | 26篇 |
2020年 | 36篇 |
2019年 | 28篇 |
2018年 | 23篇 |
2017年 | 27篇 |
2016年 | 45篇 |
2015年 | 22篇 |
2014年 | 50篇 |
2013年 | 59篇 |
2012年 | 79篇 |
2011年 | 99篇 |
2010年 | 41篇 |
2009年 | 42篇 |
2008年 | 60篇 |
2007年 | 56篇 |
2006年 | 53篇 |
2005年 | 16篇 |
2004年 | 35篇 |
2003年 | 41篇 |
2002年 | 25篇 |
2001年 | 12篇 |
2000年 | 12篇 |
1999年 | 9篇 |
1998年 | 4篇 |
1997年 | 8篇 |
1996年 | 9篇 |
1995年 | 9篇 |
1994年 | 12篇 |
1993年 | 7篇 |
1992年 | 14篇 |
1990年 | 5篇 |
1989年 | 8篇 |
1988年 | 4篇 |
1987年 | 10篇 |
1986年 | 6篇 |
1985年 | 10篇 |
1984年 | 10篇 |
1983年 | 5篇 |
1982年 | 11篇 |
1981年 | 10篇 |
1980年 | 10篇 |
1977年 | 4篇 |
1976年 | 5篇 |
1975年 | 3篇 |
1974年 | 4篇 |
1973年 | 4篇 |
1972年 | 4篇 |
排序方式: 共有1135条查询结果,搜索用时 0 毫秒
61.
Phase pure AlPO4 with the AlPO4-18 (AEI) structure was synthesised using N,N-diisopropylethyla-mine as a template. Using a combination of X-ray powder diffraction and computational methods, the location and orientation of the N,N-diisopropylethylamine molecules inside the cages of the AEI structure were determined. Thermogravimetric analysis confirmed that the number of template molecules per unit cell was consistent with the diffraction study. We unequivocally show that only one template molecule is present in each cage of the crystalline AEI material. Our work demon-strates that a combined approach enables accurate structure resolution of such complex materials. 相似文献
62.
63.
Dr. Aloysius Siriwardena Kiran Kumar Pulukuri Pancham S. Kandiyal Dr. Saumya Roy Dr. Omprakash Bande Dr. Subhash Ghosh Dr. José Manuel Garcia Fernández Dr. Fernando Ariel Martin Dr. Jean‐Marc Ghigo Dr. Christophe Beloin Dr. Keigo Ito Dr. Robert J. Woods Dr. Ravi Sankar Ampapathi Dr. Tushar Kanti Chakraborty 《Angewandte Chemie (International ed. in English)》2013,52(39):10221-10226
64.
Arunabhiram Chutia Riadh SahnounRamesh C. Deka Zhigang ZhuHideyuki Tsuboi Hiromitsu TakabaAkira Miyamoto 《Physica B: Condensed Matter》2011,406(9):1665-1672
Based on experimental findings models of amorphous graphene related carbon materials were generated using graphene nano flakes. On the optimized structures detailed local electronic properties were investigated using density functional theory. The electrical conductivities of all these models were also estimated using an in-house program based on tight-binding method. The calculated electrical conductivity values of all the models agreed well with the trend of calculated energy gap and graphitic character. 相似文献
65.
66.
Bipin Singh Koranga Mohan Narayan S. Uma Sankar 《International Journal of Theoretical Physics》2011,50(3):760-766
The neutrino parameters determined from the solar neutrino data and the anti-neutrino parameters determined from KamLAND reactor
experiment are in good agreement with each other. However, the best fit points of the two sets differ from each other by about
10−5 eV2 in mass-square difference and by about 2° in the mixing angle. Future solar neutrino and reactor anti-neutrino experiments
are likely to reduce the uncertainties in these measurements. This, in turn, can lead to a signal for CPT violation in terms
a non-zero difference between neutrino and anti-neutrino parameters. In this paper, we propose a CPT violating mass matrix
which can give rise to the above differences in both mass-squared difference and mixing angle and study the constraints imposed
by the data on the parameters of the mass matrix. 相似文献
67.
68.
N-Cinnamoyl-L-proline can be used as a template on which beta-substituted phenylalanine and beta-phenylisoserine residues can be synthesized leading to tripeptide derivatives as structural analogues of HIV protease inhibitors. 相似文献
69.
70.
Venkatraman S Anand VG PrabhuRaja V Rath H Sankar J Chandrashekar TK Teng W Senge KR 《Chemical communications (Cambridge, England)》2002,(16):1660-1661
First successful syntheses and structural characterization of new core modified meso aryl azuliporphyrins by a simple [3 + 1] methodology are reported. 相似文献