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1.
Fe3+-TiO2/SiO2薄膜催化剂的结构对其光催化性能影响   总被引:23,自引:0,他引:23  
以硅胶为载体,采用溶胶-凝胶法制备了掺杂不同量Fe3 的TiO2光催化剂(Fe3 -TiO2/SiO2)。以氙灯为光源,罗丹明B为目标降解物,对其光催化活性进行了研究.结果表明,Fe3 -TiO2/SiO2比TiO2纳米粉有更好的催化活性,Fe3 的最佳掺入量为0.03%.罗丹明B在粉体和膜催化剂的作用下遵循不同的光催化反应机理.根据XRD,SEM,Raman,XPS和FTIR的表征结果可认为,TiO2在SiO2表面薄膜化和Ti-O-Si键的形成是催化活性提高和降解机理不同的主要原因.  相似文献   
2.
采用射频等离子增强化学气相沉积(RF-PECVD)工艺制备非晶硅(a-Si:H)薄膜,KBr衬底在175-275℃范围内变化,用傅立叶红外光谱仪(FTIR)测试KBr衬底上的薄膜红外光谱峰随衬底温度的变化情况,结合红外光谱峰的理论分析确定薄膜中氢含量随衬底温度的变化规律.光谱式椭圆偏振仪中用ForouhiBloomer(FB)模型拟合得到薄膜的折射率(n),消光系数(k),膜厚及光学禁带宽度(Eg),并用扫描电镜(SEM)断面分析对椭偏仪测试结果的准确性进行验证.根据Tauc公式推出薄膜的Eg和截止波长,并和FB模型得到的结果进行了比较,Eg(FB)和Eg(Tauc)的差值在0.015eV内.  相似文献   
3.
碳薄膜电极材料在电分析化学中的应用   总被引:1,自引:0,他引:1  
郏建波 《化学进展》2007,19(11):1800-1805
由于具有一系列的优点,碳材料被广泛应用于电分析化学.新型碳电极材料的开发及其性质研究对电分析化学的发展起着重要的推动作用.最近报道了一些制备新型碳薄膜电极材料的方法,因为制备方法不同,这些碳薄膜材料的电化学性质如电位窗、稳定性、导电性也存在显著的差异.目前电位窗宽、背景电流低、稳定性高、表面不易被电极产物钝化的碳薄膜电极材料的研究非常活跃.本文综述了采用不同方法制备的一些碳薄膜电极材料如硼掺杂的金刚石薄膜、无定形碳和纳米晶体碳薄膜材料等在电分析化学中应用.  相似文献   
4.
A polypiperazine amide (PA)/polysulfone (PSF) thin film composite (TFC) was prepared by interfacial polymerization (IP) using a trimesoyl chloride hexane solution as the oil phase and a piperazine aqueous solution as the water phase on a porous polysulfone hollow fiber substrate. Its separating behaviors were investigated systematically to various salts such as NaCl, KCI, Na2SO4,MgCl2, CaCl2 and MgSO4, showing the highest rejection rate to Na2SO4, the second to MgSO4, the third to MgCl2 and CaCl2, and the lowest to KCI, NaCl, being 99%, 98%, 70%, 60%, 15% and 10% respectively. Under an increasing pressure or with time, the rejection rate of the TFC rises to a plateau. To various concentration of the feed, the rejection rate reduced gradually with the higher concentration.  相似文献   
5.
Cu(SCN)2-水系电沉积制备CuSCN薄膜   总被引:4,自引:0,他引:4       下载免费PDF全文
用电化学沉积法,以水作溶剂,在ITO透明导电玻璃上制得p-CuSCN薄膜。探讨了Cu(SCN)2-在水溶 液中的不稳定性及EDTA络合对提高CuSO4和KSCN水溶液稳定性的作用。研究结果表明,未加EDTA络合 剂时,CuSO4和KSCN在水溶液中将分解成CuSCN和(SCN)x;加入EDTA可以制得稳定的CuSO4和KSCN的 水溶液;在-400mV恒电位下,在EDTA与Cu2 的摩尔比为1∶1的水溶液中可以制备出在可见光区透光性好 的CuSCN薄膜,薄膜的平均粒径约为50nm,是p型的β- CuSCN半导体,光学带隙为3.8eV,测得的表面电导 率为0.8×10-3S/cm。  相似文献   
6.
A nano-Au modified TiO2 electrode was prepared via the oxidation of Ti sheet in flame and subsequent modification with gold nanoparticles. The results of SEM and TEM measurements show that the Au nanoparticles are well dispersed on TiO2 surface. A near 2-fold enhancement in photocurrent was achieved upon the modification with Au nanoparticles. From the results of photocurrent and electrochemical impedance experiments it was found that the flatband potential of nano-Au/TiO2 electrode negatively shifted about 100 mV in 0.5 mol/L Na2SO4 solutions compared with that of bare TiO2 electrode. The improvement of photoelectrochemical performance was explained by the inhibition for charge recombination of photo-induced electrons and holes, and the promotion for interracial charge-transfer kinetics at nano-Au/TiO2 composite film. Such nanometal-semiconductor composite films have the potential application in improving the performance of photoelectrochemical solar cells.  相似文献   
7.
Metal nanowire array films were prepared by electrodepositing Cu, Ag, Ni, Co and Cu-Ag on porous anodic alumina film. Optical transmittance of both the porous anodic alumina film and metal nanowire array film was measured in the wavelength range of 400---2600 nm under an obliquely incident light. The experimental results show that metal nanowire array films exhibit a prominent polarization function. It was found that optical polarization properties can be improved by choosing suitable kinds of electrodepositing metal, controlling the shape and length of nanowire, and changing the incident angle.  相似文献   
8.
Viscosity is one of the most important properties of colloids in mixing, transportation, stabilization, energy consumption, and so on. According to Einstein‘s viscosity equation, the viscosity of a colloidal dispersion increases with the increase of particle concentration. And the equation can be applicable to all micro-particle dispersions, because the effect of solvation films coated on particles can be neglectable in that case. But with the decrease of particle size to nano-scale, the formation of solvation films on nano-particles can greatly affect the viscosity of a dispersion, and Einstein‘s equation may not be applicable to this case. In this work, one kind of micro-size silica particle and two kinds of nano-size silica particles were used to investigate the effect of solvation films on dispersion viscosity, dispersed in water and ethyl alcohol solvents, respectively. The results of theoretical calculation and experimental investigation show that the increase of viscosity is contributed from solvation films by more than 95 percent for nano-particle dispersions, while less than 10 percent for micro-particle dispersions.  相似文献   
9.
BrФnsted acid ionic liquids were successfully applied to the electrochemical synthesis of polyaniline films on platinum electrode surfaces by using cyclic voltammetry. The scanning electron micrographs showed distinct changes in morphological structures. The films exhibited quite dense packing and good ordering of polymer dendrite as compared with those prepared using conventional hydrochloric acid, indicating that Bronsting acid ionic liquids might be promising alternatives to dual medium-dopants in the synthesis of conducting polymers.  相似文献   
10.
佘平平  汪正浩 《中国化学》2005,23(7):806-810
In this paper, the chronoamperometry was used to study the charging processes of polyethylenedioxythiophene (PEDOT) modified electrodes in the potential range where PEDOT was in the oxidized state. The results show that the charging behaviors of the PEDOT films are well agreed with the exhausted finite diffusion model. The dependence of the capacitance values of the films on potential and concentration of solution was also studied in this potential range.  相似文献   
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