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991.
The electrochemical formation of Mg-Li alloys was investigated in a molten LiCl-KCl(58-42 mol%)eutectic melt at 723 K. The cyclic voltammogram for a Mo electrode showed that the electroreduction of Li~ proceeds in a single step and the deposition potential of Li metal was -2.40 V(vs.Ag/AgCl).For Mg electrode,the electroreduction of Li~ takes place at less cathodic potential than that at the Mo electrode which was caused by the formation of Mg-Li alloys.Phase of the deposited Mg-Li alloys could be controlled by the electrolysis potential,and the samples were characterized by X-ray diffraction and scanning electron microscopy. The results showed thatα-Mg andβ-Li phases were obtained at -2.35 and -2.55 V,respectively.  相似文献   
992.
笼状烃金刚烷的新合成方法   总被引:4,自引:0,他引:4  
笼状烃金刚烷的新合成方法米镇涛郭建维邱立勤(天津大学化工学院天津300072)关键词金刚烷,沸石,催化异构金刚烷(三环[3.3.1.1[3,7]癸烷)是一种周正对称、非常稳定的笼状烃,是由10个碳原子和16个氢原子构成的环状四面体碳氢化合物,基本骨...  相似文献   
993.
We generalize the result of Hamhalter and Pták showing that an inner product space whose dimension is either a nonmeasurable cardinal or an arbitrary cardinal is complete iff its lattice of strongly closed subspaces possesses at least one state or one completely additive state, respectively. Moreover, we show that this lattice of any separable space possesses many-finite measures, and we give the Gleason analogue for them.  相似文献   
994.
乳化液膜法粗萘精制机理的研究   总被引:2,自引:0,他引:2  
本文采用水和表面活性剂组成的乳化液膜对粗萘精制机理进行了研究,通过考察表面活性剂类型浓度以及内外相比例对液膜选择性和渗透速率的影响,建立了粗萘在液膜精制中的热力学模型。实验结果表明,粗萘中硫茚,甲基萘在液膜中具有较大的分离系数;表面活性剂类型是影响液膜选择性的主要因素;表面活性剂浓度和内外相比例则影响液膜的渗透能力。  相似文献   
995.
采用水热法以HF作为结构调控剂合成了主要暴露(001)面的锐钛矿TiO2纳米片,通过光沉积方法分别合成了负载Ru和RuO2物种的光催化剂。利用X射线衍射、透射电镜和氢气程序升温还原等分析表征了催化剂的结构性质。通过光解水产氧反应来研究催化剂的催化性能,详细考察了Ru含量、负载方式以及氧化和还原处理等因素的影响,光解水产氧速率的差异证明了Ru物种在不同晶面的电荷-空穴分离效应。与负载单一助催化剂的Ru/TiO2和RuO2/TiO2样品相比,活性最优的0.5%Ru-1.0%RuO2/TiO2样品由于负载了双助催化剂,其催化活性得到更大的提高,证实了在锐钛矿TiO2上的晶面电荷-空穴分离效应.  相似文献   
996.
Syngas, the mixture of CO and H2, is a key feedstock to produce methanol and liquid fuels in industry, yet limited success has been made to develop clean syngas production using renewable solar energy. We demonstrated that syngas with a benchmark turnover number of 1330 and a desirable CO/H2 ratio of 1:2 could be attained from photoelectrochemical CO2 and H2O reduction in an aqueous medium by exploiting the synergistic co‐catalytic effect between Cu and ZnO. The CO/H2 ratio in the syngas products was tuned in a large range between 2:1 and 1:4 with a total unity Faradaic efficiency. Moreover, a high Faradaic efficiency of 70 % for CO was acheived at underpotential of 180 mV, which is the lowest potential ever reported in an aqueous photoelectrochemical cell. It was found that the combination of Cu and ZnO offered complementary chemical properties that lead to special reaction channels not seen in Cu, or ZnO alone.  相似文献   
997.
A selective and sensitive ultra‐high performance liquid chromatography with tandem mass spectrometry method was developed and validated for the determination and pharmacokinetic study of (+)‐8‐hydroxypinoresinol‐4’‐O‐β ‐D‐glucopyranoside, prinsepiol‐4‐O‐β‐D‐glucopyranoside, (+)‐pinoresinol‐4,4’‐di‐O‐β‐D‐glucopyranoside, and (−)‐massoniresinol 3α‐O‐β‐D‐glucopyranoside in rat plasma after the oral administration of a Valeriana amurensis extract. The analytes and ethyl 4‐hydroxybenzoate (internal standard) were separated on a Waters ACQUITY UPLC HSS T3 chromatographic column. The detection was performed on a triple quadrupole tandem mass spectrometer in multiple reaction monitoring mode using an electrospray ionization source operating in negative ionization mode. The linear ranges (ng/mL) of the standard curves were 0.39–154.00, 0.62–244.70, 0.50–198.60, and 0.34–134.50 for (+)‐8‐hydroxypinoresinol‐4’‐O‐β‐D‐glucopyranoside, prinsepiol‐4‐O‐β‐D‐glucopyranoside, (+)‐pinoresinol‐4,4’‐di‐O‐β‐D‐glucopyranoside, and (−)‐massoniresinol 3α‐O‐β‐D‐glucopyranoside, respectively. The inter‐ and intra‐day precisions were less than 11.0%, the accuracies were between −5.9 and 7.7%, and the extraction recoveries of the four analytes were > 81.2% from rat plasma. The method was successfully applied to a pharmacokinetic study of the four analytes after oral administration of a Valeriana amurensis extract to rats. The developed method has the potential for pharmacokinetic analysis and to provide additional information in the clinical application of Valeriana amurensis.  相似文献   
998.
V. N. Ryadovikov  A. N. Aleev  E. N. Ardashev  A. G. Afonin  V. P. Balandin  S. G. Basiladze  S. F. Berezhnev  G. A. Bogdanova  M. Yu. Bogolyubsky  A. M. Vischnevskaya  V. Yu. Volkov  A. P. Vorobiev  A. G. Voronin  V. F. Golovkin  S. N. Golovnia  S. A. Gorokhov  N. I. Grishin  Ya. V. Grishkevich  G. G. Ermakov  P. F. Ermolov  I. N. Erofeeva  V. N. Zapolsky  E. G. Zverev  D. E. Karmanov  V. I. Kireev  A. A. Kiriakov  V. N. Kramarenko  A. V. Kubarovsky  N. A. Kouzmine  L. L. Kurchaninov  G. I. Lanshikov  A. K. Leflat  M. M. Merkin  G. Ya. Mitrofanov  V. S. Petrov  Yu. P. Petukhov  A. V. Pleskach  V. V. Popov  V. M. Ronjin  V. N. Ryadovikov  V. A. Senko  M. M. Soldatov  L. L. Tikhonova  N. F. Furmanec  A. G. Kholodenko  Yu. P. Tsyupa  N. A. Shalanda  A. I. Yukaev  V. I. Yakimchuk 《Physics of Atomic Nuclei》2016,79(2):144-154
The results of an analysis of data from the SERP-Е-184 experiment devoted to studying mechanisms of the production of charmed particles in proton–nucleus interactions at 70 GeV and their decays are presented. The data in question were obtained upon irradiating the SVD-2 active target consisting of carbon, silicon, and lead plates with a beam of 70-GeV protons. A detailed simulation on the basis of the FRITIOF7.02 and GEANT3.21 code packages made it possible to optimize event-selection criteria and to calculate the detection efficiency for Λc+ baryons. After selecting a signal from the threebody decay of a Λc+ baryon, the inclusive cross section for its production at near-threshold energies, its lifetime, and the parameter of the A dependence of the cross section were found. The Λc+ -baryon yields are tabulated along with data from other experiments and theoretical predictions.  相似文献   
999.
W. Sprößig In this paper, we propose a new adaptive method for frequency‐domain identification problem of discrete LTI systems. It is based on a dictionary that is consisting of normalized reproducing kernels. We prove that the singular values of the matrix generated by this dictionary converge to zero rapidly; this makes it quite efficient in representing the original systems with only a few elements. For different systems, it results in different selected sequences from the dictionary, that is, its adaptivity. Meanwhile, the stability of results is automatically guaranteed according to the structure of the dictionary. Two examples are presented to illustrate the idea. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
1000.
A double-helical octanuclear Cu(II) wheel 1 with 2.88 nm diameter was prepared through the reaction of a clinical medicine, telmisartan, with copper sulfate. Central copper ions can be partially replaced by bivalent zinc and cobalt ions and fully exchanged by trivalent iron ions. The properties of central metal ion-exchanged variants are much different from those of 1. Central metal ion exchange might be regarded as a powerful and effective method to modify properties from one crystalline material to another only by varying central metal ions under moderate conditions.  相似文献   
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