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931.
Liu Yuren Lu Yanxin Xie Yali Wang Yonghai Du Youling Tan Jin Meng Bonian R. S. Seymour 《Journal of Radioanalytical and Nuclear Chemistry》1991,151(1):83-93
This paper introduces the principles, instrumentation, implementation, and industrial applications of an on-line thermal neutron prompt-gamma element analysis system (using a252Cf neutron source, Am–Be neutron source, or neutron generator). The energy resolution of the system at the H prompt-gamma full-energy photopeak (2.22325 MeV) is 3.6 keV. The concentration measurement error of Al2O3, FeO3, CaO, and SiO2 is ±0.3%, ±0.1%, ±0.4%, and ±0.4%, respectively. The system has been tested on-site at both the Shandong and the Zhengzhou Aluminium Works. Our preliminary on-site measurements confirm that the stability, reliability, measurement range, and accuracy of the system can meet the requirements of the aluminium production process. Facilitation of this measurement at aluminium plants is expected to reduce plant costs by over 3 million dollars annually through reduced energy consumption, more rapid qualification of pulps being mixed during the production process, and in reduced labor costs.Other participants of Shandong and Zhenghou Aluminium Works are: Wang Aili, Zengshen, Dei Jianguo and Lu Jinnan, Wang Deyu, Jin Hequan. 相似文献
932.
以二苯腈二氯化钯为催化剂,在固液相转移条件下,芳基磺酰氯能与N,N-双烷基取代丙烯酰胺发生偶联反应,生成柏应的E式不饱和酰胺。 相似文献
933.
934.
Tolerance interval for exponential distribution 总被引:1,自引:0,他引:1
Tolerance interval is a kind of interval that assures the probability of at least a given proportion of population falls into
the interval attains to a fixed level. It is widely needed in various industrial practices and business activities, such as
product design, reliability analysis, and quality inspection. However, comparing to its widely needs, the research on it is
still quite limited. In this paper, we propose a numerical method to compute the tolerance interval for exponential distribution.
As the simulation study illustrates, our method performs consistently well as the sample size varies. In particular, its good
performance for small sample endows itself broadly potential usefulness in practice. 相似文献
935.
Yukun Wang Feng Chen Zhuoxin Liu Zijie Tang Qi Yang Yan Zhao Shanyi Du Qiang Chen Chunyi Zhi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(44):15854-15858
Multiple stretchability has never been demonstrated as supercapacitors because the hydrogel used cannot fully recover after being heavily deformed. Now, a highly reversibly stretchable all‐polymer supercapacitor was fabricated using a developed double network hydrogel (DN hydrogel) as electrolyte and pure polypyrrole (PPy) as electrode. The DN hydrogel provides excellent mechanical properties, which can be stretched up to 500 % many times and then restore almost 100 % of the original length. To fabricate the fully recoverable stretchable supercapacitor, we annealed a free‐standing pure conducting polymer film as electrode so that the electrodes induced retardance is minimized. The as‐fabricated DN hydrogel/pure conducting polymer supercapacitors can be perfectly recovered from 100 % strain with almost no residual deformation left and the electrochemical performance can be maintained even after 1000 stretches (but not bending). 相似文献
936.
Shukun Wei Xiaoyou Hu Lingyu Du Linlin Zhao Hongjuan Xue Chaolun Liu James J. Chou Jin Zhong Yimin Tong Shuqing Wang Bo OuYang 《Molecules (Basel, Switzerland)》2021,26(5)
Hepatitis C Virus (HCV) is the key cause of chronic and severe liver diseases. The recent direct-acting antiviral agents have shown the clinical success on HCV-related diseases, but the rapid HCV mutations of the virus highlight the sustaining necessity to develop new drugs. p7, the viroporin protein from HCV, has been sought after as a potential anti-HCV drug target. Several classes of compounds, such as amantadine and rimantadine have been testified for p7 inhibition. However, the efficacies of these compounds are not high. Here, we screened some novel p7 inhibitors with amantadine scaffold for the inhibitor development. The dissociation constant (Kd) of 42 ARD-series compounds were determined by nuclear magnetic resonance (NMR) titrations. The efficacies of the two best inhibitors, ARD87 and ARD112, were further confirmed using viral production assay. The binding mode analysis and binding stability for the strongest inhibitor were deciphered by molecular dynamics (MD) simulation. These ARD-series compounds together with 49 previously published compounds were further analyzed by molecular docking. Key pharmacophores were identified among the structure-similar compounds. Our studies suggest that different functional groups are highly correlated with the efficacy for inhibiting p7 of HCV, in which hydrophobic interactions are the dominant forces for the inhibition potency. Our findings provide guiding principles for designing higher affinity inhibitors of p7 as potential anti-HCV drug candidates. 相似文献
937.
Veličković Jelena Đ. Andrić Deana Roglić Goran Tešic Živoslav Lj. Milojković-Opsenica Dušanka M. 《平面色谱法杂志一现代薄层色谱法》2004,17(4):255-260
JPC – Journal of Planar Chromatography – Modern TLC - The chromatographic behavior of fourteen 1-arylpiperazine derivatives has been studied by thin-layer chromatography on both silica... 相似文献
938.
The aim of this study was to investigate whether ginsenoside Rg1 could be transported into rat pulmonary epithelial cells and its transport behavior and efflux through the cells. A high-performance liquid chromatography coupled with 2487 UV-vis detector at 203 nm was applied. The mobile phase was 0.05% phosphate-acetonitrile (75:25, v/v). Cells were incubated with Rg1 (100 microg/mL) for a specific time, then lysed and sonicated in methanol to extract intracellular Rg1. Cells incubated with Rg1 and verapamil or KCN were processed by the same method. A 20 microL aliquot of sample was injected into the HPLC system to determine Rg1 concentration. The results showed that Rg1 could be transported into the epithelial cells with peak concentration of 1.28 microg/10(5) cells at 0.5 h. Metabolic inhibitor KCN and P-glycoprotein inhibitor verapamil could increase Rg1 concentration within the cells, indicating that efflux of Rg1 was energy-dependent and P-gp was likely to be involved. This is the first time that the transport behavior and efflux of Rg1 through rat pulmonary epithelial cells has been demonstrated. The phenomenon that Rg1 concentration in the cells decreased whereas that in the medium remained high indicated that a more effective means of drug administration should be found. 相似文献
939.
Hongmei Zhang Weiqiang Zhou Yukou Du Ping Yang Chuanyi Wang 《Electrochemistry communications》2010,12(7):882-885
A facile, one-step and template-free electrodeposition method has been developed for the first time to prepare porous Pt nanoflowers. The flowerlike architectures were confirmed by SEM, and further structurally characterized by XRD and electrochemical analyses. Compared to conventional nanosized Pt catalysts, as-prepared Pt nanoflowers exhibit remarkably higher catalytic activity and stronger poisoning-tolerance for the methanol electro-oxidation, and thus they are anticipated to find interesting applications in many important fields such as energy and catalysis. 相似文献
940.
Dengtai Chen Prof. Dr. Xijiang Han Prof. Dr. Yunchen Du Dr. Hsing‐Lin Wang Prof. Dr. Ping Xu 《Chemphyschem》2016,17(1):46-50
The cyclobutane cleavage reaction is an important process and has received continuous interest. Herein, we demonstrate the visible laser‐driven cleavage reaction of cyclobutane in crystal form by using in situ Raman spectroscopy. Silver(I) coordination‐induced strain and thermal effects from the laser irradiation are the two main driving forces for the cleavage of cyclobutane crystals. This work may open up a new avenue for studying cyclobutane cleavage reactions, as compared to the conventional routes using ex situ techniques. 相似文献