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991.
I. S. Berezovska V. V. Yanishpolskii V. A. Tertykh M. V. Burmistr K. M. Sukhyy 《Journal of Thermal Analysis and Calorimetry》2006,86(1):93-96
Effect of the presence
of I-4 Me-Ph ionene in the supramolecular template (cetyltrimethylammonium
bromide) on formation of porous structure of silicas has been studied. As-synthesized
nanocomposites were characterized by using thermal analysis. Nitrogen adsorption–desorption
measurements, X-ray diffraction and scanning electronic microscopy were applied
to determine adsorption-structural characteristics and morphology of particles
of the mesoporous templated silicas prepared in basic media. 相似文献
992.
Chao Guo Guo‐Xin Jin Fusong Wang 《Journal of polymer science. Part A, Polymer chemistry》2004,42(19):4830-4837
2,6‐Diacetylpyridinebis (2,6‐diisopropylani) iron dichloride, a late‐transition metal catalyst for olefin polymerization, was supported on SBA‐15 successfully and the property of the supported catalyst was carefully studied. Ethylene polymerization was systematically investigated in the presence of MAO under various conditions employing this type of catalyst system. In general, after support, a decrease in the catalytic activity was observed and higher molecular weight and fibrous morphology of polyethylene were obtained. The “extrusion polymerization” phenomenon was observed in ethylene polymerization by using the supported catalyst system. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4830–4837, 2004 相似文献
993.
采用溶胶-凝胶方法,在不同的实验条件下获得平均粒径从15到25nm左右的纳米TiO22颗粒.利用这些颗粒制备出的纳米多孔薄膜,应用于染料敏化纳米薄膜太阳电池. 通过x射线 衍射仪分析,得到TiO22颗粒的晶相以及晶粒度大小,用透射电子显微镜观察 了纳米TiO22颗粒的形貌和尺寸.应用于太阳电池的纳米TiO22多 孔膜,经基于布朗诺尔-埃米特-泰 勒(BET)的多层吸附理论的比表面积测试和孔径分布测试,获得了多孔膜的微
关键词:
溶胶-凝胶法
2')" href="#">纳米TiO22
染料敏化
太阳电池 相似文献
994.
995.
The new nanocomposites, by means of an in situ sol–gel process consisting of metallocene polyethylene–octene elastomer (POE) and titanium tetraisopropylate (TTIP), were investigated. In addition, the acrylic acid grafted POE (POE‐g‐AA) was studied as an alternative to POE. Fourier transform infrared (FTIR) spectroscopy, a dynamic mechanical analyzer (DMA) spectrometer, an X‐ray diffractometer (XRD), differential scanning calorimetry (DSC), a thermogravimetric analyzer (TGA), an Instron mechanical tester, and a scanning electron microscope (SEM) were used to characterize and examine the samples. The results indicate that the POE‐g‐AA/TiO2 hybrid could have a positive effect on the properties of the POE/TiO2 hybrid because the carboxylic acid groups of acrylic acid should act as coordination sites for the titania phase to form a Ti? O? C chemical bond. The strength of interfacial bonding between the polymer chains and the ceramic phase depended on the amount of TiO2, as shown by the change in glass‐transition temperature (Tg) with TiO2 content. The result of mechanical and thermal tests showed that both the tensile strength and the Tg increased to a maximum value and then decreased with an increasing of TiO2 because excess particles (e.g., greater than 10 wt % TiO2) might cause separation or segregation between the organic and inorganic phases. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 4272–4280, 2004 相似文献
996.
A NEW METHOD FOR DEOXIDIZATION AND CHLORINATION OF REFINED ILMENITE WITH HIGH MAGNESIA AND CALCIA CONTENTS 总被引:3,自引:0,他引:3
BinLi ZhangfuYuan WenbingLi CongXu 《中国颗粒学报》2004,2(2):84-88
A new process is proposed to utilize refined ilmenite with high magnesia and calcia contents, which is the main secondary resource from vanadium-bearing titaniferous magnetite in Panzhihua, covering about 40% of the world‘s titanium. The refined ilmenite was first deoxidized to separate the iron in the ore in order to enrich the titanium. The mechanism of chlorination of the titanium-rich slag was analyzed using the HSC chemistry software, Following deoxidation, a tandem fluidized bed was applied to chlorinating the titanium-rich slag. Modeling of the tandem fluidized bed explains how this serial operation can effectively improve the convention ratio of TiO2 to TiCl4. 相似文献
997.
Petr Kluson Hana Luskova Libor Cerveny Tomas Cajthaml 《Reaction Kinetics and Catalysis Letters》2005,86(2):281-289
Summary Unexpected photocatalytic properties of templated precursors of nanostructured TiO2(titania) were observed in the development of a generally applicable method for the synthesis of a truly nanocrystalline titania
at temperatures compatible with plastic catalytic supports. It specifically comprised the “self-activation”feature of the
TiO2nanostructured precursor (produced within the non-ionic surfactant template) likely induced by the preparation method “imprinted”photoactivity.
Such behavior complied with the principal aim to develop the photocatalytic material without recourse to any significant thermal
step. 相似文献
998.
Marchetti S. G. Cagnoli M. V. Alvarez A. M. Bengoa J. F. Gallegos N. G. Yeramián A. A. Mercader R. C. 《Hyperfine Interactions》2002,139(1-4):33-40
We have synthesized mesoporous MCM-41 and have used it as a support for iron particles to be employed as a catalyst in the Fischer–Tropsch reaction. The solids were characterized by Mössbauer spectroscopy, X-ray diffraction, BET, TGA, CO chemisorption and volumetric oxidation. Although the catalyst showed a high CO conversion when it was used in the hydrocarbon synthesis from CO and H2 (14.3% at 1 h of reaction time) mainly methane was formed. The high methane production is likely related to the very small size of the metal particles obtained. We suggest some ways to improve the selectivity. 相似文献
999.
Mingna Xiong Shuxue Zhou Bo You Limin Wu 《Journal of Polymer Science.Polymer Physics》2005,43(6):637-649
Homogeneous organic–inorganic hybrid materials with excellent thermal and optical performance were successfully prepared via the mixing of (3‐methacryloxypropyl)trimethoxysilane‐capped acrylic resin with titania synthesized by sol–gel approaches. The effects of the titania content, amount of water, and pH in the sol–gel and the ratio of the solvents (butyl acetate and ethanol) on the structures and properties of the hybrid materials were studied. More titania, more water, and base catalysis in the sol–gel process and a higher ratio of butyl acetate to ethanol for the hybrids led to a larger size and a more compact structure of the titania phase. Increasing the titania content dramatically improved the glass‐transition temperature, UV‐shielding properties, and refractive index for the hybrid materials, and it did not reduce their optical transparency. In general, better thermal stability and optical properties were achieved for the hybrid materials prepared with less water, lower pH values (e.g., acidic or neutral conditions), and a lower ratio of butyl acetate to ethanol. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 637–649, 2005 相似文献
1000.
Chun Hui ZHOU? Xiao Nian LI Dong Sheng TONG Yi Fen ZHU Zhong Hua GE College of Chemical Engineering Materials Science Zhejiang University of Technology Hangzhou 《中国化学快报》2005,(2)
The intercalation of polynuclear hydroxy metal cations in smectites affords porouspillared clays which show great potential applications involving separations,adsorptionand catalysis.Though the range of pillared agents has been considerably enlarged1since its invention,aluminum Keggion ions[Al13O4(OH)]7+24and silicon cations arestill often used as pillaring species.Pinnavaia reported that introduction of silica intointerlayers by ion exchange of swollen clays with silicon acetylacetonate cat… 相似文献