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101.
Zhaoyang Zhang Xinxin Xue Chuangshe Li Sijing Cheng Lei Han Haixia Chen Huaibin Zheng Yanpeng Zhang 《Optics Communications》2012,285(17):3627-3630
We demonstrate the coexisting four-wave mixing (FWM) signal and six-wave mixing (SWM) signal which can be enhanced both by electromagnetically induced transparency (EIT) and optical pumping effect in a common three-level and open four-level inverted-Y type systems of 85Rb. We also analyze the effect of optical pumping in different energy level systems by arranging laser beams and comparing the strength of the increased and reduced absorption caused by optical pumping. 相似文献
102.
GAO Lei ZHANG Jing HE Chang SHEN SuLing ZHANG Yi LIU HongTao SUN QingJiang LI YongFang 《中国科学:化学(英文版)》2013,56(7):997-1003
A new star-shaped donor-acceptor molecule has been synthesized for application as the donor material in solution-processed bulk-heterojunction organic solar cells (OSCs). The molecule consists of a triphenylamine (TPA) unit as the core and a donor unit with three arms containing benzo[1,2,5]thiadiazole (BT) acceptor units and 5,5’’-dihexyl-2,2′:3′,2″-terthiophene (tTh) end groups. The molecule, denoted S(TPA-BT-tTh), exhibits a broad absorption band in the wavelength range 300-650 nm and high hole mobility of 1.1×10 -4 cm2 V -1 s 1 . An OSC device based on S(TPA-BT-tTh) as donor and [6,6]-phenyl C71 -butyric acid methyl ester (PC 70 BM) as the acceptor (1:3, w/w) exhibited a power conversion efficiency of 2.28% with a short circuit current density of 6.39 mA/cm2 under illumination of AM.1.5, 100 mW/cm2 . 相似文献
103.
In this study, a series of coumarin derivatives were designed and synthesized, their structures were characterized using nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS) testing methods. In the pharmacological experiment, two behavior-monitoring methods, the forced swim test (FST) and the tail suspension test (TST), were used to determine the antidepressant activity of coumarin derivatives. Compounds that showed potential activity were analyzed for their effects on 5-hydroxytryptamine (5-HT) levels in the brains of mice. Molecular docking experiments to simulate the possible interaction of these compounds with the 5-HT1A receptor was also be predicted. The results of the pharmacological experiments showed that most coumarin derivatives exhibited significant antidepressant activity. Among these compounds, 7-(2-(4-(4-fluorobenzyl)piperazin-1-yl)-2-oxoethoxy)-2H-chromen-2-one (6i) showed the highest antidepressant activity. The results of the measurement of 5-HT levels in the brains of mice indicate that the antidepressant activity of coumarin derivatives may be mediated by elevated 5-HT levels. The results of molecular docking demonstrated that compound 6i had a significant interaction with amino acids around the active site of the 5-HT1A receptor in the homology model. The physicochemical and pharmacokinetic properties of the target compounds were also predicted using Discovery Studio (DS) 2020 and Chemdraw 14.0. 相似文献
104.
105.
106.
Yue Zhao Lei Chang Wei Yuan Yu-xin Liu 《The European Physical Journal C - Particles and Fields》2008,56(4):483-492
We give a general relation between the chiral susceptibility and the thermodynamical potential and a relation between the
chiral susceptibility and the condition for furcations to appear in the Wigner solution(s) in the Nambu–Jona-Lasinio (NJL)
model. We find that the chiral susceptibility is a quantity able to represent the appearance of furcation in the solution(s)
of the gap equation and the concavo–convexity of the thermodynamical potential in the NJL model. It indicates that the chiral
susceptibility can identify the stability of the states and the chiral phase transition in NJL model. We propose that analyzing
the chiral susceptibility may play an important role in studying the chiral phase transition in approaches superior to the
NJL model. 相似文献
107.
Zhihao Geng 《Physics letters. A》2010,375(2):214-219
The doping and temperature dependence of the electronic Raman response in cuprate superconductors is studied within the kinetic energy driven superconducting mechanism. It is shown that the temperature dependent depletion at low-energy shifts is faster in the B1g symmetry than in the B2g symmetry. In analogy to the domelike shape of the doping dependent superconducting transition temperature, the maximal peak energy in the B2g channel occurs around the optimal doping, and then decreases in both underdoped and overdoped regimes. Moreover, the overall density of Cooper pairs increases with increasing doping in the underdoped regime. 相似文献
108.
109.
本文研究了开链及环状硅氢化合物中硅原子上取代基的电子效应和立体效应对Si-H键伸缩振动频率的影响。 相似文献
110.
H. -H. Lei P. P. T. Sah und Ch. Shih 《Fresenius' Journal of Analytical Chemistry》1937,109(3-4):135-136
Ohne Zusammenfassung 相似文献