全文获取类型
收费全文 | 849篇 |
免费 | 35篇 |
国内免费 | 7篇 |
专业分类
化学 | 635篇 |
晶体学 | 11篇 |
力学 | 29篇 |
数学 | 30篇 |
物理学 | 186篇 |
出版年
2023年 | 11篇 |
2022年 | 15篇 |
2021年 | 14篇 |
2020年 | 20篇 |
2019年 | 33篇 |
2018年 | 31篇 |
2017年 | 18篇 |
2016年 | 29篇 |
2015年 | 25篇 |
2014年 | 39篇 |
2013年 | 79篇 |
2012年 | 62篇 |
2011年 | 57篇 |
2010年 | 38篇 |
2009年 | 32篇 |
2008年 | 52篇 |
2007年 | 28篇 |
2006年 | 37篇 |
2005年 | 30篇 |
2004年 | 31篇 |
2003年 | 19篇 |
2002年 | 16篇 |
2001年 | 4篇 |
2000年 | 11篇 |
1999年 | 4篇 |
1997年 | 5篇 |
1996年 | 6篇 |
1995年 | 4篇 |
1994年 | 10篇 |
1993年 | 3篇 |
1992年 | 6篇 |
1991年 | 9篇 |
1990年 | 3篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 7篇 |
1985年 | 3篇 |
1984年 | 8篇 |
1982年 | 6篇 |
1981年 | 9篇 |
1980年 | 7篇 |
1979年 | 7篇 |
1978年 | 4篇 |
1977年 | 9篇 |
1976年 | 7篇 |
1975年 | 8篇 |
1974年 | 5篇 |
1973年 | 3篇 |
1969年 | 3篇 |
1962年 | 2篇 |
排序方式: 共有891条查询结果,搜索用时 15 毫秒
1.
Nonlinear Dynamics - In this paper, a novel robust tracking control strategy for nonlinear unmatched uncertain systems is formulated using the event-based adaptive dynamic programming (ADP)... 相似文献
2.
A new third‐order WENO scheme is proposed to achieve the desired order of convergence at the critical points for scalar hyperbolic equations. A new reference smoothness indicator is introduced, which satisfies the sufficient condition on the weights for the third‐order convergence. Following the truncation error analysis, we have shown that the proposed scheme achieves the desired order accurate for smooth solutions with arbitrary number of vanishing derivatives if the parameter ε satisfies certain conditions. We have made a comparative study of the proposed scheme with the existing schemes such as WENO‐JS, WENO‐Z, and WENO‐N3 through different numerical examples. The result shows that the proposed scheme (WENO‐MN3) achieves better performance than these schemes. 相似文献
3.
Surapuraju Pavan Kumar Raju Mallikarjun Narayanam Banothu Kranthi Kumar Sreeram Tejaswee Saranjit Singh 《Chromatographia》2015,78(19-20):1245-1250
4.
5.
6.
7.
Nagu A. Vasikerappa K. Gidyonu P. Prathap Ch. Venkata Rao M. Rama Rao K. S. David Raju B. 《Research on Chemical Intermediates》2020,46(5):2669-2681
Research on Chemical Intermediates - MgO-supported Ni catalysts were selectively catalysed by the hydrogenation of benzonitrile to benzylamine in continuous flow at atmospheric pressure without any... 相似文献
8.
Arulraj Ruba A. Gajjela Raju Chauthe Siddheshwar Kisan Bagadi Muralidhararao Mathur Arvind 《Chromatographia》2022,85(6):497-506
Chromatographia - In drug discovery environment, determination of residual solvents is indispensable and requires rapid analysis covering a maximum number of commonly used solvents especially with... 相似文献
9.
Electrospinning is a well-known technique since 1544 to fabricate nanofibers using different materials like polymers, metals oxides, proteins, and many more. In recent years, electrospinning has become the most popular technique for manufacturing nanofibers due to its ease of use and economic viability. Nanofibers have remarkable properties like high surface-to-volume ratio, variable pore size distribution (10–100 nm), high porosity, low density, and are suitable for surface functionalization. Therefore, electrospun nanofibers have been utilized for numerous applications in the pharmaceutical and biomedical field like tissue engineering, scaffolds, grafts, drug delivery, and so on. In this review article, we will be focusing on the versatility, current scenario, and future endeavors of electrospun nanofibers for various biomedical applications. This review discusses the properties of nanofibers, the background of the electrospinning technique, and its emergence in chronological order. It also covers the various types of electrospinning methods and their mechanism, further elaborating the factors affecting the properties of nanofibers, and applications in tissue engineering, drug delivery, nanofibers as biosensor, skin cancer treatment, and magnetic nanofibers. 相似文献
10.
Dr. Pengfei Wu Prof. Dr. Adriana Pietropaolo Dr. Mariagrazia Fortino Dr. Masayoshi Bando Prof. Dr. Katsuhiro Maeda Dr. Tatsuya Nishimura Shuhei Shimoda Dr. Hiroyasu Sato Prof. Dr. Naofumi Naga Prof. Dr. Tamaki Nakano 《Angewandte Chemie (International ed. in English)》2023,62(29):e202305747
Optically active, hyperbranched, poly(fluorene-2,4,7-triylethene-1,2-diyl) [poly(fluorenevinylene)] derivatives bearing a neomenthyl group and a pentyl group at the 9-position of the fluorene backbone at various ratios acted as a chirality donor (host polymers) efficiently included naphthalene, anthracene, pyrene, 9-phenylanthracene, and 9,10-diphenyanthracene as a chirality acceptor (guest molecules) in their interior space in film as well as in solution, with the guest molecules exhibiting intense circular dichroism through chirality transfer with chirality amplification. The efficiency of the chirality transfer was much higher with higher-molar-mass polymers than lower-molar-mass ones as well as with hyperbranched polymers compared to the analogous linear ones. The hyperbranched polymers include the small molecules in their complex structure without any specific interactions at various stoichiometries. The included molecules may have ordered intermolecular arrangement that may be somewhat similar to those of liquid crystals. Naphthalene, anthracene, and pyrene included in the polymer exhibited efficient circularly polarized luminescence, where the chirality was remarkably amplified in excited states, and anthracene exhibited especially high anisotropies in the emission on the order of 10−2. 相似文献