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111.
112.
杨明坤 《中国无机分析化学》2015,5(2):73-75
采用Li2B4O7和LiBO2的混合熔剂(67∶33)熔融制样,波长色散X射线荧光光谱法测定金红石中TiO2,TFe,P,SiO2,Al2O3,MnO,CaO,Cr2O3,MgO,ZrO2,HfO2等组分。实验中样品和熔剂的质量比为1∶14,以溴化锂(LiBr)作脱模剂,采用高频熔炉在1 150℃熔融90s进行制样,所得熔片均匀、强度高、成型良好。方法用于金红石实际样品的测定,结果同参考值或化学分析方法的结果相吻合,相对标准偏差(RSD,n=10)P为3.8%、Al2O3为2.8%,其它均小于2%,能够满足实际测定工作的需要。 相似文献
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114.
Dr. Xin‐Yao Yu Hao Bin Wu Le Yu Fei‐Xiang Ma Prof. Xiong Wen Lou 《Angewandte Chemie (International ed. in English)》2015,54(13):4001-4004
Hollow structures of rutile TiO2, and especially with non‐spherical shape, have rarely been reported. Herein, high‐quality rutile TiO2 submicroboxes have been synthesized by a facile templating method using Fe2O3 submicrocubes as removable templates. Compared to other rutile TiO2 nanomaterials, the as‐prepared rutile TiO2 submicroboxes manifest superior lithium storage properties in terms of high specific capacity, long‐term cycling stability, and excellent rate capability. 相似文献
115.
1. Introduction Titania TiO2 is a polymorphic oxide, inclusive of two common polymorphs: anatase (space group I41/amd, a0=0.37852 nm, c0=0.95139 nm) and rutile (space group P42/mnm, a0=0.45933 nm, c0=0.29592 nm) , both with octahedrally coordinated tetragonal structures. Anatase is a metastable structure and readily transforms to the stable morphic rutile upon heating (Gribb & Banfield, 1997). Because of their wide application in ceramics, catalysis, electronics, sensors and electrodes, they… 相似文献
116.
The adsorption of carbon monoxide on a clean and hydroxylated rutile (110) surface has been investigated using a periodic approach at DFT/B3LYP level. The hydroxylated surface was modelled by considering both terminal and bridging OH groups. The variation of the electrophilicity of the Lewis acid site near these groups was evaluated by taking into account the adsorbate–substrate distance, the magnitude of the interaction energy and the blue-shift of the adsorbed CO stretching frequency. The results obtained suggest that the electrophilicity increases in proximity to OH terminal groups, and decreases near the OH bridging groups. 相似文献
117.
The present work reports an investigation of physico-chemical properties and catalytic activity of the pure, sulfated and
iron containing sulfated rutile. The catalysts were characterized by X-ray Diffraction, FT-IR, BET surface area, TG and NH3-TPD measurements. The catalytic activity of the prepared catalysts towards liquid phase Friedel-Crafts alkylation of toluene
with benzyl chloride was tested.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
118.
Spectroscopic study of polycrystalline TiO2 doped with vanadium 总被引:2,自引:0,他引:2
The structure of coordination sites (V4+ ions) and their spatial distribution in the polycrystalline titanium dioxide (rutile) lattice were studied by ESR. It was found that at low degrees of doping, at [V4+] < 0.5 at.%, the vanadium ions are isotropically distributed in the rutile lattice. At [V4+] > 0.5 at.% a new microphase with the mixed composition {TiO2—VO2} is formed. The mixed microphase has a noticeably narrower band gap than the initial TiO2. Comparison of the photocurrent spectra and the plots of the integral photocurrent vs. vanadium content with the structural data obtained using ESR spectroscopy showed that the formation of the {TiO2—VO2} microphases deteriorates the photoelectrochemical properties of the modified photoelectrodes. Synthetic procedures interfering the formation of such microphases in the doped rutile are discussed. 相似文献
119.
Conducting polyaniline-rutile TiO2 nanocomposites for the development of high-k dielectric materials
Inorganic dielectrics encapsulated in an organic matrix are showing excellent promise as novel dielectric materials. In this work, firstly highly organized crystalline nanoparticles of rutile TiO2 were synthesized by acid hydrolysis of titanium isopropoxide at room temperature. Then we developed a novel dielectric material consisting of highly organized rutile TiO2/polyaniline (PAni) nanocomposites by in-situ chemical oxidative polymerization. The structural, morphological, conducting, and dielectric properties of the rutile TiO2/PAni nanoparticles have been evaluated by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution-transmission emission microscopy (HR-TEM), four-point probe technique, CV (Capacitance versus Voltage), and Impedance analyzer. The nanocomposites show 70 times higher permittivity compared to rutile nanoparticles and much higher compared to anatase/PAni (ES) nanocomposites at 10 MHz. Large interfacial polarizations, nanostructure, and dopant levels are the key factors for the large dielectric constant of the nanocomposites. The rutile/PAni (ES) nanocomposites might see potential uses in super-capacitors, gate dielectric in transistors, and capacitive-type gas sensors. 相似文献
120.