全文获取类型
收费全文 | 43314篇 |
免费 | 1923篇 |
国内免费 | 1064篇 |
专业分类
化学 | 23060篇 |
晶体学 | 674篇 |
力学 | 2022篇 |
综合类 | 91篇 |
数学 | 4413篇 |
物理学 | 16041篇 |
出版年
2022年 | 481篇 |
2021年 | 637篇 |
2020年 | 749篇 |
2019年 | 720篇 |
2018年 | 843篇 |
2017年 | 753篇 |
2016年 | 1112篇 |
2015年 | 815篇 |
2014年 | 1147篇 |
2013年 | 2178篇 |
2012年 | 2162篇 |
2011年 | 2517篇 |
2010年 | 1822篇 |
2009年 | 1788篇 |
2008年 | 1955篇 |
2007年 | 1888篇 |
2006年 | 1698篇 |
2005年 | 1484篇 |
2004年 | 1364篇 |
2003年 | 1173篇 |
2002年 | 1106篇 |
2001年 | 1490篇 |
2000年 | 1075篇 |
1999年 | 933篇 |
1998年 | 708篇 |
1997年 | 669篇 |
1996年 | 596篇 |
1995年 | 541篇 |
1994年 | 492篇 |
1993年 | 424篇 |
1992年 | 489篇 |
1991年 | 505篇 |
1990年 | 487篇 |
1989年 | 437篇 |
1988年 | 453篇 |
1987年 | 438篇 |
1986年 | 380篇 |
1985年 | 443篇 |
1984年 | 462篇 |
1983年 | 340篇 |
1982年 | 388篇 |
1981年 | 376篇 |
1980年 | 315篇 |
1979年 | 394篇 |
1978年 | 377篇 |
1977年 | 392篇 |
1976年 | 390篇 |
1975年 | 339篇 |
1974年 | 317篇 |
1973年 | 334篇 |
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
1.
Chuprin A. S. Belova S. A. Bugaenko M. G. Vologzhanina A. V. Loktev A. S. Voloshin Ya. Z. Buznik V. M. Dedov A. G. 《Kinetics and Catalysis》2022,63(1):108-116
Kinetics and Catalysis - A new ruthenium(II) cage complex with polar terminal groups in the apical substituents has been synthesized; the molecular design of the complex contributes to the... 相似文献
2.
High Energy Chemistry - Modification of Polyvinylidene fluoride (PVDF) by radiation grafting is a research hotspot in recent years. In this study, the monomer 2-Hydroxyethyl methacrylate (HEMA) was... 相似文献
3.
Alawainati F. A. Manaa H. Henari F. Z. Biyiklioglu Z. Arslan T. Jaafar A. 《Journal of Applied Spectroscopy》2021,88(5):951-957
Journal of Applied Spectroscopy - Detailed measurements of nonlinear optical properties and optical limiting for four phthalocyanine (Pc) derivatives (PcCo, PcCu, PcMn, and PcSi) are reported. The... 相似文献
4.
Siberian Mathematical Journal - A lattice homomorphism between quasi-Banach lattices is known to be compact if and only if it is a sum of a series of rank one lattice... 相似文献
5.
Hongjin Wang Tengfei Long Hao Zhang Meng Li Qi Sun Xin Zhai Lixin Sun 《Biomedical chromatography : BMC》2022,36(4):e5301
3,4-Difluorobenzyl(1-ethyl-5-(4-((4-hydroxypiperidin-1-yl)-methyl)thiazol-2-yl)-1H-indol-3-yl)carbamate (NAI59), a small molecule with outstanding therapeutic effectiveness to anti-pulmonary fibrosis, was developed as an autotaxin inhibitor candidate compound. To evaluate the pharmacokinetics and plasma protein binding of NAI59, a UPLC–MS/MS method was developed to quantify NAI59 in plasma and phosphate-buffered saline. The calibration curve linearity ranged from 9.95 to 1990.00 ng/mL in plasma. The accuracy was −6.8 to 5.9%, and the intra- and inter-day precision was within 15%. The matrix effect and recovery, as well as dilution integrity, were within the criteria. The chromatographic and mass spectrometric conditions were also feasible to determine phosphate-buffered saline samples, and it has been proved that this method exhibits good precision and accuracy in the range of 9.95–497.50 ng/mL in phosphate-buffered saline. This study is the first to determine the pharmacokinetics, absolute bioavailability, and plasma protein binding of NAI59 in rats using this established method. Therefore, the pharmacokinetic profiles of NAI59 showed a dose-dependent relationship after oral administration, and the absolute bioavailability in rats was 6.3%. In addition, the results of protein binding showed that the combining capacity of NAI59 with plasma protein attained 90% and increased with the increase in drug concentration. 相似文献
6.
7.
Bingjie Chen Dr. Lianhai Zu Dr. Yao Liu Dr. Ruijing Meng Yutong Feng Prof. Chengxin Peng Feng Zhu Tianzi Hao Jiajia Ru Prof. Yonggang Wang Prof. Jinhu Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(8):3161-3166
Incorporating nanoscale Si into a carbon matrix with high dispersity is desirable for the preparation of lithium-ion batteries (LIBs) but remains challenging. A space-confined catalytic strategy is proposed for direct superassembly of Si nanodots within a carbon (Si NDs⊂C) framework by copyrolysis of triphenyltin hydride (TPT) and diphenylsilane (DPS), where Sn atomic clusters created from TPT pyrolysis serve as the catalyst for DPS pyrolysis and Si catalytic growth. The use of Sn atomic cluster catalysts alters the reaction pathway to avoid SiC generation and enable formation of Si NDs with reduced dimensions. A typical Si NDs⊂C framework demonstrates a remarkable comprehensive performance comparable to other Si-based high-performance half LIBs, and higher energy densities compared to commercial full LIBs, as a consequence of the high dispersity of Si NDs with low lithiation stress. Supported by mechanic simulations, this study paves the way for construction of Si/C composites suitable for applications in future energy technologies. 相似文献
8.
9.
We study the full counting statistics of transport electrons through a semiconductor two-level quantum dot with Rashba spin–orbit (SO) coupling, which acts as a nonabelian gauge field and thus induces the electron transition between two levels along with the spin flip. By means of the quantum master equation approach, shot noise and skewness are obtained at finite temperature with two-body Coulomb interaction. We particularly demonstrate the crucial effect of SO coupling on the super-Poissonian fluctuation of transport electrons, in terms of which the SO coupling can be probed by the zero-frequency cumulants. While the charge currents are not sensitive to the SO coupling. 相似文献
10.
JPC – Journal of Planar Chromatography – Modern TLC - A new high-performance thin-layer chromatographic (HPTLC) method has been developed for the simultaneous estimation of... 相似文献