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71.
Shi-Kuo Li Chuan-Hao Li Fang-Zhi Huang Yang Wang Yu-Hua Shen An-Jian Xie Qiong Wu 《Journal of nanoparticle research》2011,13(7):2865-2874
Uniform Cu2O hollow spheres fabricated by single-crystalline particles (smaller than 20 nm) are facile synthesized in ethylene glycol
(EG) solution by a simple solvothermal route without using pre-fabricated templates and reductive agents. EG in this protocol
is not only used as a solvent, complexing agent, and reducing agent, but also served as a structure-directing agent for the
formation of hollow structure. By control of reaction conditions, such as reaction time, temperature, and the anions, the
morphology and structure of the hollow spheres can be tuned. A coordination adsorption and oriented attachment and Ostwald
ripening mechanism is proposed for explaining the formation process of hollow Cu2O spheres in EG solution; and importantly, the hollow Cu2O spheres exhibit an excellent property for the electro-catalytic oxidization of ascorbic acid in acetic acid buffer solution.
Moreover, the hollow spherical Cu2O particles could be potentially applied in catalysis, sensor, and as model for fundamental research. 相似文献
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77.
Zhihong Liu Minghao Zheng Xin Yan Qiong Gu Johann Gasteiger Johan Tijhuis Peter Maas Jiabo Li Jun Xu 《Journal of computer-aided molecular design》2014,28(9):941-950
Predicting compound chemical stability is important because unstable compounds can lead to either false positive or to false negative conclusions in bioassays. Experimental data (COMDECOM) measured from DMSO/H2O solutions stored at 50 °C for 105 days were used to predicted stability by applying rule-embedded naïve Bayesian learning, based upon atom center fragment (ACF) features. To build the naïve Bayesian classifier, we derived ACF features from 9,746 compounds in the COMDECOM dataset. By recursively applying naïve Bayesian learning from the data set, each ACF is assigned with an expected stable probability (p s ) and an unstable probability (p uns ). 13,340 ACFs, together with their p s and p uns data, were stored in a knowledge base for use by the Bayesian classifier. For a given compound, its ACFs were derived from its structure connection table with the same protocol used to drive ACFs from the training data. Then, the Bayesian classifier assigned p s and p uns values to the compound ACFs by a structural pattern recognition algorithm, which was implemented in-house. Compound instability is calculated, with Bayes’ theorem, based upon the p s and p uns values of the compound ACFs. We were able to achieve performance with an AUC value of 84 % and a tenfold cross validation accuracy of 76.5 %. To reduce false negatives, a rule-based approach has been embedded in the classifier. The rule-based module allows the program to improve its predictivity by expanding its compound instability knowledge base, thus further reducing the possibility of false negatives. To our knowledge, this is the first in silico prediction service for the prediction of the stabilities of organic compounds. 相似文献
78.
采用CCSD(T)/aug-cc-pVTZ//B3LYP/6-311+G(2df,2p)方法对HO2+H2S反应及单分子水参与其主通道的微观机理和速率常数进行了研究.结果表明,HO2+H2S反应主通道为生成产物为H2O2+HS的通道,其表观活化能为14.94 kJ/mol.考虑单分子水对主产物通道的影响发现,所得的势能面比无水参与的反应复杂得多,经历了H2O…HO2+H2S(RW1),HO2…H2O+H2S(RW2)和H2O…H2S+HO2(RW3)3个通道,RW1~RW6共6个路径.其中通道RW1是水分子参与HO2+H2S反应主通道的优势通道.在216.7~298.2K温度范围内通道RW1的有效速率常数呈现出正温度系数效应,在298 K时,k’RW 1/ktotal达到54.2%,表明在实际大气环境中水分子对HO2+H2S反应的主通道具有明显影响. 相似文献
79.
Tong Shen Rong Xiao Qiong Wang Lijuan Yang Nong Wang 《Journal of Dispersion Science and Technology》2014,35(3):435-440
The absorption spectrum of Sudan red III (SR) in oil solutions and a series of O/W microemulsion with surfactant sodium dodecyl sulfate (SDS) has been determined by the UV-Vis spectrophotometer. We found that an association interaction existed between the stain SR and anionic surfactant SDS in water/mixed oil/SDS microemulsions. By measuring the absorbance of Sudan red in a series of microemulsions which has different R values and using the appropriate association models to analyze the experimental data, we obtain the association constants of SR and SDS, and the values of thermodynamics functions of associationΔr G m has also been calculated from the association constants. 相似文献
80.
Jinlong Jiang Hao Huang Qiong Wang Weijun Zhu Junying Hao Weimin Liu 《Surface and interface analysis : SIA》2014,46(3):139-144
The titanium/silicon mono‐ and co‐doped amorphous carbon films were deposited by mid‐frequency magnetron sputtering Ti target, Si target, and Ti80S20 alloy target, respectively. The effects of doped elements on the composition, surface morphology, microstructure, and mechanical and tribological properties of the films were investigated. The results reveal that the ratio of sp3 and sp2 carbon bonds of the films is regulated between 0.28 and 0.62 by a combination of Ti and Si dopant. The addition of small amounts of silicon leads to an increase in sp3 bonds and disorder degree of the sp2 carbon. The co‐doped film exhibits significantly superior friction performance than the mono‐doped films. The ultra‐low friction (μ < 0.01) was achieved under a load of 2 N in ambient air with 40% RH. By comparing to the mono‐and co‐doped films, it is thought that the sp3/sp2 ratio of the films may play a key role for the superlow friction. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献