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101.
聚双环戊二烯反应注射成型 总被引:3,自引:0,他引:3
本文介绍了国外有关聚双环戊二烯反应注射成型的研究进展,讨论了国内进行聚双环戊二烯反应注射成型开发研究的现实意义,并对这一领域的发展进行了展望 相似文献
102.
SYNTHESIS OF MESOPOROUS POLY(STYRENE-co-MALEIC ANHYDRIDE)/SILICA HYBRID MATERIALS VIA A NONSURFACTANT-TEMPLATED SOL-GEL PROCESS* 总被引:1,自引:0,他引:1
Jie-bin Pang Kun-yuan Qiu Yen Wei Department of Polymer Science Engineering College of Chemistry Molecular Engineering Peking University Beijing China. Department of Chemistry Drexel University Philadelphia Pennsylvania USA. 《高分子科学》2000,(5):469-472
Mesoporous poly (styrene-co-maleic anhydride)/silica hybrid materials have been prepared. The synthesis wasachieved by the HCl-catalyzed sol-gel reactions of tetraethyl orthosilicate (TEOS) and styrene-maleic anhydride copolymerin the presence of 3-aminopropyl triethoxysilane (APTES) as a coupling agent and citric acid as a nonsurfactant template orpore-forming agent, followed by ethanol extraction. Characterization results from nitrogen sorption isotherms and powder X-ray diffraction indicate that polymer-modified mesoporous materials with large specific surface areas (e.g. 900 m~2/g) andpore volumes (e.g. 0.6 cm~3/g) could be prepared. As the citric acid concentration is increased, the specific surface areas, porevolumes and pore diameters of the hybrid materials increase. 相似文献
103.
Zhiming Liu Jiming Hao Lixin Fu Tianle Zhu Junhua Li Xiangyu Cui 《Reaction Kinetics and Catalysis Letters》2003,80(1):45-52
SnO2/Al2O3 catalyst prepared by sol-gel method showed higher activity than those prepared by impregnation method, and their activity
was significantly improved by pre-treatment in the reaction gas. The increased activity is closely related to the agglomeration
of SnO2 species and the re-exposure of Al2O3, which was previously covered by dispersed SnO2 species.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
104.
Jijun Qiu Weidong Yu Xiangdong Gao Xiaomin Li 《Journal of Sol-Gel Science and Technology》2007,44(3):235-239
Ordered porous TiO2 films, including TiO2 nanotube arrays, are fabricated by a sol-gel dip-coating approach via ZnO nanorod templates obtained from aqueous solution
approach. The results indicate that the morphologies of ordered porous TiO2 films have been great affected by the sol-gel dip-coating cycle number. Open-ended TiO2 nanotube arrays can be obtained in optimum dip-coating cycle numbers. The TiO2 nanotubes with the inner diameter matching well with the diameters of ZnO nanorods, are well assembled and separate each
other. When the cycle number is less than this optimum value, no intact porous TiO2 film can be obtained. As the cycle number is larger than this optimum value, an ordered porous TiO2 film with many throughout holes is formed. The evolutive mechanism of ordered porous TiO2 films is proposed. 相似文献
105.
106.
Wei Luo Xiang Kai Fu Li Hua Ma 《中国化学快报》2007,18(7):883-886
The high quality TiO2, MoO3-doped WO3 electrochromic film was prepared by the sol–gel method for the first time. The sol, which has hydrogen peroxide (H2O2) and oxalic acid (H2C2O4), was very stable at room temperature and quite suitable for the deposition of films. The WO3 electrochromic film prepared from this doped sol had excellent performance, such as short response time, no cracks, good adhesion to the substrate, high coloring efficiency and longevity of service. 相似文献
107.
Masahiro Toyoda Yukio Hamaji Kunisaburo Tomono 《Journal of Sol-Gel Science and Technology》1997,9(1):71-84
The sol-gel processing was applied to the fabrication of PbTiO3 fibers. Pb(CH3COO)2·3H2O and Ti(OC3H
7
i
)4 were refluxed with stirring in 2-methoxyethanol to form Pb-methoxyethoxide and Ti-methoxyethoxide, respectively, followed
by mixing with stirring in 2-methoxyethanol to form Pb−Ti double alkoxide. The hydrolysis and polycondensation reaction of
this double alkoxide gave polymerized products, and as a result the viscosity of the solution increased, suggesting that linear
polymers were produced through the hydrolysis and polycondensation reaction. Homogeneous PbTiO3 gel fibers were drawn from the spinnable viscous solutions, which were wellcrystallized into perovskite type PbTiO3 at 650°C. The heat-treated fibers were a few centimeters long and from 10 to 100 μm in diameter. The fiber was made up of
extremely uniform grains. Electron diffraction revealed a preferred growth of (101) planes along the fiber axis, which might
be due to the linear molecular characteristics of the alkoxide. 相似文献
108.
利用Sol-gel法结合氧化铝模板技术制备了La0.8Ca0.2MnO3纳米线, 并研究了两种热处理方法对 La0.8Ca0.2MnO3纳米线结构和形貌的影响. 快速升温到800 ℃得到的La0.8Ca0.2MnO3纳米线较粗, 其直径大于氧化铝模板的孔径, 而经过缓慢升温到400 ℃预处理再升温到800 ℃得到的La0.8Ca0.2MnO3纳米线, 其直径和氧化铝模板的孔径相当, 都约为35 nm. X射线衍射和透射电镜分析结果表明, 两种方法得到的 La0.8Ca0.2MnO3纳米线都是具有钙钛矿结构的属于单斜晶系的多晶材料. 相似文献
109.
110.
提出了一种铁矿粉热加工生产工艺中亚铁含量测定的新方法。在氮气保护下,用盐酸溶出样中的亚铁,在硫磷混酸介质中以重铬酸钾标准溶液滴定,并对溶样条件进行了研究。该方法简单、快速、准确,已成功地应用于氧化催化法生产氧化铁中亚铁的控制分析和成品鉴定。 相似文献