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101.
102.
氨基树脂透明防火涂料的发展概况 总被引:1,自引:0,他引:1
介绍了透明防火涂料的基本组成、类型、特点及其应用 ,概述了透明防火涂料的发展现状。 相似文献
103.
Rigid, microporous silica rods, prepared previously by the sol-gel process, were infiltrated with three triacrylate monomers to give sequential interpenetrating networks (IPNs). The three commercially available triacrylate monomers are glycerol propoxy triacrylate (GPTA), trimethylolpropane triacrylate (TMPTA) and pentaerythritol triacrylate (PETA). Each solution containing a photoinitiator was allowed to infiltrate the silica rod, after which the sample was UV irradiated to polymerize the triacrylate monomer. Emphasis was placed on establishing the infiltration and polymerization conditions leading to optically transparent composites. For comparison, one of the triacrylates (GPTA) was introduced into a hydrolyzing sol-gel formulation containing TEOS, ethanol, water and acid catalyst, to effect a simultaneous IPN. The sequential IPN and the simultaneous IPN samples gave similar transmission curves, despite differences in skeletal density.1992 Fulbright Visiting Scholar, on leave from Marie Curie Sklodowska University, Lublin, Poland. 相似文献
104.
利用薄层光谱电化学技术研究了辣根过氧化物酶(HRP)及其化合物的氧化还原过程。指出HRP可在固体电极上进行直接电子传递,该电极反应不是酶中二硫键的还原,而是血红素辅基中心金属离子的氧化态转变。测定了HRP(Fe~(3+)/Fe~(2+))电对的标准氧化还原电位和电化学动力学参数,讨论了HRP氧化性中间物的电化学性质。 相似文献
105.
Recently, low temperature synthesis of ITO thin film of low resistivity is desired in the field of LCD (Liquid Crystalline
Display) production. This paper describes the results of experiment to produce ITO thin film from a sol containing crystalline
ITO particles and alkoxides of In and Sn. Crystallization temperature of ITO thin film obtained from the sol mixed with ITO
powder was lower than that of ITO from the sol without ITO powder. Furthermore, the resistivity of the former ITO thin film
was lower than that of the latter. It was assumed that these results were attributed to the promotion effect of ITO crystalline
particles to crystalize the amorphous ITO gel at lower temperature. This low temperature crystallization effect plays an important
role in enhancing the crystallinity and electric conductivity of ITO thin film from sol-gel process. 相似文献
106.
共沉淀法制备掺钕钇铝石榴石透明激光陶瓷的研究 总被引:4,自引:2,他引:4
掺钕钇铝石榴石(Nd∶YAG)多晶透明陶瓷具有良好的化学稳定性、光学性能和耐高温性能,是一种很有前途的激光工作物质。以Al(NO3).9H2O,Y2O3,Nd2O3和NH4HCO3为原料,(NH4)2SO4为静电稳定剂,正硅酸乙酯为添加剂,采用共沉淀法和反滴定方式于1100℃合成出分散均匀、团聚程度轻、YAG立方晶相的Nd∶YAG纳米前驱体粉末,经1700℃真空烧结5 h制备出Nd∶YAG透明陶瓷材料。采用TG-DTA,XRD,TEM,FT-PL和FEG-ESEM等测试手段对Nd∶YAG陶瓷材料进行了表征。研究结果表明:前驱体粉末在800℃时为无定型态,当温度达到890℃时析出大量的YAlO3(YAP)和少量的Y3Al5O12(YAG)晶体,当温度达到1012℃时就全部转化为YAG立方晶相;前驱体纳米粉末中存在团聚。Nd∶YAG陶瓷材料的激光工作波长为1.065μm,和相同组分的单晶相比存在轻微的红移现象;随着透射光波长的增加,透光率逐渐增加,在可见光区透光率约为45%,在近红外光区透光率约为58%。 相似文献
107.
Shannon Haymond Jerzy K. Zak Yoshiyuki Show James E. Butler Gerald T. Babcock Greg M. Swain 《Analytica chimica acta》2003,500(1-2):137-144
The spectroelectrochemical responsiveness of an optically transparent diamond electrode (OTE) toward ferrocene was investigated. A freestanding, mechanically polished, boron-doped diamond disk (0.38 mm thick and 8 mm in diameter) served as the OTE for UV-Vis transmission spectroelectrochemical measurements. A specially designed, thin-layer spectroelectrochemical cell was constructed for the measurements in which ferrocene was electrooxidized to ferricinium ion via a one-electron redox reaction. The oxidation reaction product was spectroscopically monitored in the ultraviolet (λ=252, 285 nm) region of the electromagnetic spectrum. Well-defined and highly stable spectroelectrochemical responses were observed for this type of diamond OTE. The results indicate that diamond is a useful OTE material for spectroelectrochemically studying nonaqueous redox reactions. 相似文献
108.
Flexible transparent fluorinated nanohybrid with innovative heat‐resistance property—new technology proposal for fabrication of transparent materials using “crystalline” polymer 下载免费PDF全文
Muhammad Abdullah Al Mamun Youichi Soutome Qi Meng Atsuhiro Fujimori 《Journal of Polymer Science.Polymer Physics》2015,53(23):1674-1690
A new technology for the production of transparent material, using a “crystalline” polymer, is proposed in this study. In addition, a heat‐resistant transparent flexible plastic film with a high hydrophobic surface and a thermal decomposition temperature near 400 °C was created. Partially fluorinated crystalline polymer with switchboard‐type lamellae results high transparency as a consequence of the formation of a high‐density amorphous structure based on high‐temperature drawing just below the melting point at 250 °C. Melt‐compounding with montmorillonite modified by the long‐chain quaternary phosphonium with high coverage induces formation of a nanohybrid that retains transparency and also results in an increase in the thermal degradation temperature by over 50 °C. Through this technology, which results in heat‐resistance, transparency, and flexibility, the nano‐micro‐millimeter structures of solid‐state polymers are hierarchically controlled, which enables the creation of new materials. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1674–1690 相似文献
109.
110.
Daniel Ruprecht Achim Schädle Frank Schmidt 《Numerical Methods for Partial Differential Equations》2013,29(4):1367-1390
The pole condition approach for deriving transparent boundary conditions is extended to the time‐dependent, two‐dimensional case. Nonphysical modes of the solution are identified by the position of poles of the solution's spatial Laplace transform in the complex plane. By requiring the Laplace transform to be analytic on some problem‐dependent complex half‐plane, these modes can be suppressed. The resulting algorithm computes a finite number of coefficients of a series expansion of the Laplace transform, thereby providing an approximation to the exact boundary condition. The resulting error decays super‐algebraically with the number of coefficients, so relatively few additional degrees of freedom are sufficient to reduce the error to the level of the discretization error in the interior of the computational domain. The approach shows good results for the Schrödinger and the drift‐diffusion equation but, in contrast to the one‐dimensional case, exhibits instabilities for the wave and Klein–Gordon equation. Numerical examples are shown that demonstrate the good performance in the former and the instabilities in the latter case. © 2012 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013 相似文献