全文获取类型
收费全文 | 1689篇 |
免费 | 274篇 |
国内免费 | 161篇 |
专业分类
化学 | 1172篇 |
晶体学 | 14篇 |
力学 | 92篇 |
综合类 | 11篇 |
数学 | 149篇 |
物理学 | 686篇 |
出版年
2024年 | 2篇 |
2023年 | 46篇 |
2022年 | 32篇 |
2021年 | 51篇 |
2020年 | 92篇 |
2019年 | 79篇 |
2018年 | 54篇 |
2017年 | 47篇 |
2016年 | 67篇 |
2015年 | 79篇 |
2014年 | 70篇 |
2013年 | 99篇 |
2012年 | 118篇 |
2011年 | 149篇 |
2010年 | 115篇 |
2009年 | 117篇 |
2008年 | 129篇 |
2007年 | 105篇 |
2006年 | 112篇 |
2005年 | 91篇 |
2004年 | 63篇 |
2003年 | 48篇 |
2002年 | 41篇 |
2001年 | 50篇 |
2000年 | 35篇 |
1999年 | 42篇 |
1998年 | 25篇 |
1997年 | 22篇 |
1996年 | 32篇 |
1995年 | 21篇 |
1994年 | 29篇 |
1993年 | 16篇 |
1992年 | 12篇 |
1991年 | 9篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1988年 | 7篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有2124条查询结果,搜索用时 29 毫秒
1.
Geng Tianfeng Du Chunyu Cheng Xinqun Xu Xing Jian Jiyuan He Xiaoshu Zuo Pengjian Yin Geping 《Journal of Solid State Electrochemistry》2019,23(1):101-108
Journal of Solid State Electrochemistry - Li-rich layered oxide (LrLO) cathode has attracted much attention for Li-ion batteries in recent years due to its superior capacity of exceeding... 相似文献
2.
Julia Holz Camilla Pfeffer Hualiang Zuo Dennis Beierlein Gunther Richter Elias Klemm Ren Peters 《Angewandte Chemie (International ed. in English)》2019,58(30):10330-10334
Gold nanoparticle catalysts are important in many industrial production processes. Nevertheless, for traditional C ?C cross‐coupling reactions they have been rarely used and Pd catalysts usually give a superior performance. Herein we report that in situ formed gold metal nanoparticles are highly active catalysts for the cross coupling of allylstannanes and activated alkylbromides to form C ?C bonds. Turnover numbers up to 29 000 could be achieved in the presence of active carbon as solid support, which allowed for convenient catalyst recovery and reuse. The present study is a rare case where a gold metal catalyst is superior to Pd catalysts in a cross‐coupling reaction of an organic halide and an organometallic reagent. 相似文献
3.
4.
Wang Hongda Zhang Chunxia Zuo Tiantian Li Weiwei Jia Li Wang Xiaoyan Qian Yuexin Guo Dean Yang Wenzhi 《Analytical and bioanalytical chemistry》2019,411(29):7817-7829
Analytical and Bioanalytical Chemistry - Despite Panax quinquefolius L. serving as a crucial source for food additives, healthcare products, and herbal medicines, unawareness of the metabolome... 相似文献
5.
The present research was to investigate the effects of skimmianine (SK) in four non-small cell lung cancer (NSCLC) cells. We found that SK can significantly inhibit the growth of NSCLC cells and markedly induce apoptosis in NSCLC cells. The effects of growth inhibition and apoptosis induction were in a concentration–response relationship and caspase-dependent manner. 相似文献
6.
7.
A two-dimensional periodic Schrödingier operator is associated with every Lagrangian torus in the complex projective plane \({\mathbb C}P^2\). Using this operator, we introduce an energy functional on the set of Lagrangian tori. It turns out this energy functional coincides with the Willmore functional \(W^{-}\) introduced by Montiel and Urbano. We study the energy functional on a family of Hamiltonian-minimal Lagrangian tori and support the Montiel–Urbano conjecture that the minimum of the functional is achieved by the Clifford torus. We also study deformations of minimal Lagrangian tori and show that if a deformation preserves the conformal type of the torus, then it also preserves the area, i.e., preserves the value of the energy functional. In particular, the deformations generated by Novikov–Veselov equations preserve the area of minimal Lagrangian tori. 相似文献
8.
Yaogang Hu Peng Teng Wenyang Gao Xiaobing Zuo Lukasz Wojtas Randy W. Larsen Shengqian Ma Jianfeng Cai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(6):2501-2507
Foldamers offer an attractive opportunity for the design of novel molecules that mimic the structures and functions of proteins and enzymes including biocatalysis and biomolecular recognition. Herein we report a new class of nonnatural helical sulfono‐γ‐AApeptide foldamers of varying lengths. The crystal structure of the sulfono‐γ‐AApeptide monomer S6 illustrates the intrinsic folding propensity of sulfono‐γ‐AApeptides, which likely originates from the bulkiness of tertiary sulfonamide moiety. The two‐dimensional solution NMR spectroscopy data for the longest sequence S1 demonstrates a 10/16 right‐handed helical structure. Optical analysis using circular dichroism further supports well‐ defined helical conformation of sulfono‐γ‐AApeptides in solution containing as few as five building blocks. Future development of sulfono‐γ‐AApeptides may lead to new foldamers with discrete functions, enabling expanded application in chemical biology and biomedical sciences. 相似文献
9.
10.