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111.
黄雪峰  钱坤 《无机化学学报》2005,21(9):1437-1438
Compound [Zn(phen)3][BDA] (1) (BDA=6,6′-dibromo-2,2′-dimethoxy-1,1′-binaphthylene-4,4′-disulfonate, phen= 1,10-phenanthroline) composes of the anion part (racemic-(R,S)-6,6′-dibromo-2,2′-dimethoxy-1,1′-binaphthylene-4,4′-disulfonate ) and the cation part which consists of a racemic octahedrally coordinated zinc center defined six nitrogen atoms from three phen rings to form an inorganic chirality that can be resolution by chiral organic ligand, the 3D framework was formed through the strong H-bonding interaction between sulfonate and water. CCDC: 277924.  相似文献   
112.
The structure and characteristic of carbon nanotubes-ionic liquid gel biosensor were studied by voltammetry, microscopy and spectroscopy. Various biomolecules were electrochemically detected with this gel biosensor such as glucose oxidase and NADH. The excellent electrochemical behavior of this gel biosensor might be due to the following three main factors: (1) the inherently perfect electrochemical characteristic of multi-wall carbon nanotubes (MWNTs); (2) the better solvent effect and conductivity of ionic liquid as well as the proper interactions between MWNTs and ionic liquid; (3) the proper mixing ratio of MWNTs to ionic liquid. Meanwhile, the interactions between MWNTs and ionic liquid were carefully studied as well. It can be concluded that the non-covalent (π–π) interaction between the imidazole loop of ionic liquid and MWNTs side wall should play an important role. This work gives a further understanding of what results in the high sensitivity and selectivity of such a biosensor to some biomolecules, and provides a simple and easy approach to design new biosensors with various nano-particles and versatile ionic liquid.  相似文献   
113.
《Fluid Phase Equilibria》2005,227(2):267-274
A stability analysis of a widely used model of the Gibbs energy of fluid mixtures is presented. In that model, the solutes and the solvent are treated differently (asymmetric normalization). For the solutes, an infinitely dilute reference state is used, the ideal solution is defined using molalities, and a virial expansion in molalities is used for describing the Gibbs excess energy GE. That model is identical with the well-known Pitzer model if only uncharged molecular species are present. An unusual stability behavior of that model is observed. Instability is predicted for a wide range of concentrations in an important range of model parameters. Despite this, for principal reasons, that model does not allow determining the concentrations in coexisting phases in a physically meaningful way. For example, for binary systems it always predicts that only the pure components are globally stable. To illustrate those findings, the system hydrogen sulfide–water is discussed, for which the Pitzer model is often used in practice. For comparison with the Pitzer model the well-known Margules GE-model is used that shows no unexpected stability behavior. Conversion rules are presented that allow finding parameters for the well-behaved Margules model from those of the Pitzer model. The application is again demonstrated using the system hydrogen sulfide–water.  相似文献   
114.
《Fluid Phase Equilibria》2006,239(2):133-137
Vapour–liquid equilibria at atmospheric pressure have been determined for binary mixtures of 1,2-dibromoethane + 1,2-dichloroethane, +trichloromethane, and +1,1,2,2-tetrachloroethane. These have been shown to be thermodynamically consistent.  相似文献   
115.
采用循环伏安(CV)法和原位表面增强拉曼光谱(SERS)技术, 研究了非水体系中反应物异黄樟油和目标产物胡椒醛在粗糙铂电极上的电氧化行为, 发现胡椒醛在电位≥1.50 V时将进一步氧化, 而且从分子水平证实, 在胡椒醛的氧化电位(≥1.50 V) 下, 波长为632.8 nm的激光对胡椒醛的氧化有助催化作用. 由异黄樟油直接电氧化合成胡椒醛的电位(E)应控制在1.20 V相似文献   
116.
用密度泛函(DFT)方法,在B3LYP/6-31G**水平上对2-溴丙酸气相消除反应机理进行了研究.计算表明,反应主要是通过半极化五元环结构过渡态进行的,羧基上的氢原子协助溴原子离去,羧基氧原子帮助稳定过渡态.在B3LYP/6-311++G(3df,3pd)水平上对B3LYP/6-31G**优化的几何构型进行了单点能计算,计算所得反应的速度控制步骤的活化能为189.461 kJ•mol-1,偏离实验值((180.3±3.4) kJ•mol-1)5.08%.  相似文献   
117.
以二茂铁为起始原料,经氯汞化反应、溴代反应、Suzuki偶联反应、水解反应和取代反应等5步反应合成了一种新型的含二茂铁结构单元的有机配合物(7),其结构经1H NMR、13C NMR、IR和HR-MS(ESI-TOF)表征。电化学研究结果表明:化合物6的E1/2小于化合物7,具有较高的氧化还原活性。  相似文献   
118.
A carbon nanotube-supported NiP amorphous catalyst (NiP/CNT) was prepared by induced reduction. Benzene hydrogenation was used as a probe reaction for the study of catalytic activity. The effects of the support on the activity and thermal stability of the supported catalyst were discussed based on various characterizations, including XRD, TEM, ICP, XPS, H2-TPD, and DTA. In comparison with the NiP amorphous alloy, the benzene conversion on NiP/CNT catalyst was lower, but the specific activity of NiP/CNT was higher, which is attributed to the dispersion produced by the support, an electron-donating effect, and the hydrogen-storage ability of CNT. The NiP/CNT thermal stability was improved because of the dispersion and electronic effects and the good heat-conduction ability of the CNT support.  相似文献   
119.
Summary Mesoporous TiO2-CeO2mixed oxides (m-TiO2-CeO2) were synthesized under easy-operating neutral conditions. The structure was characterized by means of FT-IR, XRD, and N2adsorption methods. For methanol decomposition to CO and H2, the catalytic activity of the Ru/ m-TiO2-CeO2 catalyst was higher than that of the Ru/ m-TiO2.</o:p>  相似文献   
120.
利用固相微萃取气相色谱法测定非那雄胺中的溶剂残留,对固相微萃取的萃取温度、萃取时间、解吸时间和溶液的离子强度等分析条件进行了优化.该方法具有较好的线性,相关系数:二氯甲烷为0.997,三氯甲烷为0.998;相对标准偏差:二氯甲烷为2.7%,三氯甲烷为1.8%.  相似文献   
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