全文获取类型
收费全文 | 28367篇 |
免费 | 4489篇 |
国内免费 | 4153篇 |
专业分类
化学 | 21264篇 |
晶体学 | 424篇 |
力学 | 1518篇 |
综合类 | 359篇 |
数学 | 3180篇 |
物理学 | 10264篇 |
出版年
2024年 | 10篇 |
2023年 | 415篇 |
2022年 | 546篇 |
2021年 | 818篇 |
2020年 | 941篇 |
2019年 | 1017篇 |
2018年 | 838篇 |
2017年 | 769篇 |
2016年 | 1277篇 |
2015年 | 1289篇 |
2014年 | 1553篇 |
2013年 | 2078篇 |
2012年 | 2485篇 |
2011年 | 2518篇 |
2010年 | 1940篇 |
2009年 | 1845篇 |
2008年 | 2081篇 |
2007年 | 1891篇 |
2006年 | 1783篇 |
2005年 | 1521篇 |
2004年 | 1271篇 |
2003年 | 1109篇 |
2002年 | 1156篇 |
2001年 | 936篇 |
2000年 | 719篇 |
1999年 | 615篇 |
1998年 | 427篇 |
1997年 | 466篇 |
1996年 | 396篇 |
1995年 | 364篇 |
1994年 | 317篇 |
1993年 | 266篇 |
1992年 | 241篇 |
1991年 | 189篇 |
1990年 | 176篇 |
1989年 | 154篇 |
1988年 | 100篇 |
1987年 | 81篇 |
1986年 | 84篇 |
1985年 | 68篇 |
1984年 | 44篇 |
1983年 | 30篇 |
1982年 | 27篇 |
1981年 | 21篇 |
1980年 | 18篇 |
1978年 | 14篇 |
1976年 | 9篇 |
1975年 | 12篇 |
1973年 | 11篇 |
1972年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 215 毫秒
1.
Liu Zhu Sun Wen-Yang Fan Xiao-Gang Wang Dong Ye Liu 《International Journal of Theoretical Physics》2021,60(7):2412-2422
International Journal of Theoretical Physics - In this paper, we investigate Einstein-Podolsky-Rosen steering, Bell non-locality, first-order coherence and concurrence in the spin- $\frac {1}{2}$... 相似文献
2.
Nonlinear Dynamics - Epilepsy is the second largest neurological disease which seriously threatens human life and health. The one important reason of inducing epileptic seizures is ischemic stroke... 相似文献
3.
4.
Sicheng Yang Dr. Jiaoyu Ren Prof. Hong Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(7):e202103867
The drug delivery system based on nano/micromotors has become a research hot spot in recent years. However, naked micromotors may be ruptured or passivated under the complex biological environment, which will result in the leakage of drugs in advance or limited self-propulsion performance. Herein, an injectable micromotor@hydrogel drug delivery system to protect micromotors from the external environment is proposed. The micromotors were prepared through layer-by-layer assembly technology. The asymmetric decomposition of hydrogen peroxide catalyzed by the locally distributed platinum nanoparticles enabled efficient propulsion of the micromotors in low concentration of hydrogen peroxide. In order to protect micromotors, they were loaded into the Schiff base hydrogel. The micromotor@hydrogel system can be injected directly into the lesion to release micromotors in response to the environment, reducing external influence on micromotors and improving the sustained-release effect. Erythromycin (Ery) loaded into the micromotors and the micromotor@hydrogel system demonstrated excellent antibacterial effect. Micromotors released from the hydrogel underwent enhanced diffusion in the surroundings of bacteria without addition of exogenous hydrogen peroxide, which was manifested by their appearance in edge of the inhibition zone. The proposed micromotor@hydrogel drug delivery system offers a new strategy for the treatment of bacterial infections. 相似文献
5.
Hanghang Zhou Dr. Ying Luo Dr. Jun Xu Dr. Lidan Deng Prof. Dr. Zheng Wang Prof. Dr. Hong He 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(68):e202202044
Cubic-like CaTaO2N photocatalysts with high crystallinity and uniform particle size were successfully prepared by the flux-assisted nitridation method. The growth of CaTaO2N single crystals under different synthesis conditions was systematically investigated to understand the effects of the crystallinity and optical property on photocatalytic performance of CO2 reduction. Moreover, the modification of CaTaO2N single crystals with core-shell Ni−Ag bicomponent cocatalyst by two-step decoration process gave a 2.4 times higher amount of CO evolution than the deposition of sole Ag cocatalyst, because of the synergistic effects of bicomponent cocatalyst on the interfacial electron transfer and surface catalytic process. This study provides a valuable way to construct high-crystalline photocatalysts with effective bicomponent cocatalyst for visible-light-driven CO2 reduction with H2O. 相似文献
6.
Ye Jingyao Al-Jobory Alaa Zhang Qian-Chong Cao Wenqiang Alshehab Abdullah Qu Kai Alotaibi Turki Chen Hang Liu Junyang Ismael Ali K. Chen Zhong-Ning Lambert Colin J. Hong Wenjing 《中国科学:化学(英文版)》2022,65(9):1822-1828
Science China Chemistry - Destructive quantum interference (DQI) provides a unique approach to controlling the leakage current in the OFF state of molecular devices. However, the DQI in... 相似文献
7.
8.
Liu Wenbin Huang Yiwei Huang Guolin Fan Lijiao Xie Yuming Shi Jeffery 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(5):2055-2068
Journal of Radioanalytical and Nuclear Chemistry - Eco-friendly and low-cost composite, amidoxime-functionalized microcrystalline cellulose/mesoporous silica (MCC/MS-AO), were synthesized by... 相似文献
9.
Zhongxian Fan Jiaen Xie Dr. Tumpa Sadhukhan Chao Liang Can Huang Wenqing Li Tingxuan Li Dr. Pingyu Zhang Dr. Samya Banerjee Dr. Krishnan Raghavachari Dr. Huaiyi Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(3):e202103346
Four photo-catalysts of the general formula [Ir(CO6/ppy)2(L)]Cl where CO6=coumarin 6 ( Ir1 – Ir3 ), ppy=2-phenylpyridine ( Ir4 ), L=4′-(3,5-di-tert-butylphenyl)-2,2′ : 6′,2′′-terpyridine ( Ir1 ), 4′-(3,5-bis(trifluoromethyl)phenyl)-2,2′ : 6′,2′′-terpyridine ( Ir2 and Ir4 ), and 4-([2,2′ : 6′,2′′-terpyridin]-4′-yl)-N,N-dimethylaniline ( Ir3 ) were synthesized and characterized. These photostable photo-catalysts ( Ir1 – Ir3 ) showed strong visible light absorption between 400–550 nm. Upon light irradiation (465 and 525 nm), Ir1 – Ir3 generated singlet oxygen and induced rapidly photo-catalytic oxidation of cellular coenzymes NAD(P)H. Ir1 – Ir3 showed time-dependent cellular uptake with excellent intracellular retention efficiency. Upon green light irradiation (525 nm), Ir2 provided a much higher photo-index (PI=793) than the clinically used photosensitizer, 5-aminolevulinicacid (5-ALA, PI>30) against HeLa cancer cells. The observed necro-apoptotic anticancer activity of Ir2 was due to the Ir2 triggered photo-induced intracellular redox imbalance (by NAD(P)H oxidation and ROS generation) and change in the mitochondrial membrane potential. Remarkably, Ir2 showed in vivo photo-induced catalytic anticancer activity in mouse models. 相似文献
10.
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