Sol—Gel法制备CoO—SiO2膜

用Ｓｏｌ－ｇｅｌ法在浮法玻璃上制备了ＣｏＯ－ＳｉＯ２膜。用红外光谱仪,透射电镜和电子衍射仪等对薄膜的结构及光谱特性进行了研究,分析了影响着色的工艺因素。     

Influence of Protic Liquids on the Formation of Lyotropic Mesophases in Binary Systems with K-Laurate

Comparing the phase diagrams of three binary soap systems (soap: K-laurate = KC₁₂) KC₁₂/glycerol, KC₁₂/ethylene glycol and KC₁₂/butylene glycol we found alterations in the types of phase diagrams that depend on the protic solvents. A different polymorphism in the binary systems were observed which was dependent on the solvent. In the system KC₁₂/glycerol: C ? G ? H ? L ? S (C = crystalline phase, G = gel phase, H = hexagonal phase, L = lamellar phase, S = isotropic solution), in the binary system KC₁₂/E: C ? G ? L ? S, in the binary system KC₁₂/B: C ? G ? L ? S. The differences in number, position, extension and sequence of occurring mesophases are a function of the composition in the binary systems and of the temperatures. We came to the conclusion that the influence, which the solution medium exerts on the formation of structures in the binary systems, is very distinct and pronounced.     

Sol—Gel法制备SiO2—TiO2膜

本文以四氯化钛为原料，采用Ｓｏｌ－Ｇｅｌ法以浸镀方式在浮法玻璃上制备了纯ＴｉＯ２膜和ＳｉＯ２－ＴｉＯ２混合膜。用电子探针、红外光谱仪和电子衍射仪测定了薄膜的成分分布及结构演变。用紫外－可见光光谱仪测定了样品的与反射率曲线。研究了溶液浓度、粘度、提拉速度及热处理温度等因素对镀膜质量的影响。     

Formation of Mullite from Sol-Gel Mixtures and Kaolinite

Critical analyses of published reaction studies on kaolinite, and sol-gel and powder mixtures equivalent to 3Al₂O₃·2SiO₂ mullite, were made. Supplementary experiments on reactions of kaolinite at different rates of heating were analyzed. Complete atomic homogeneity of precursors results in formation of tetragonal mullite. Colloidal precursors initially form spinel which reacts with the remaining silica by a diffusion-nucleation mechanism to form orthorhombic mullite. Precursors with intermediate atomic homogeneity follow both reaction paths. Kaolinite with a layer lattice structure has two-dimensional atomic homogeneity. Both reaction routes are followed and their degree of interaction is dependent on the crystallinity and impurities of the kaolinite.     

Compositional Dependence of Apatite Formation in Sol-Gel Derived Organic-Inorganic Hybrids

In the present study, we report the bioactivity of PDMS-CaO-SiO₂-P₂O₅ hybrid materials prepared by a sol-gel method. The apatite formation on the surface of the specimen, after soaking in the simulated body fluid (SBF), was analyzed by thin-film X-ray diffraction (TF-XRD) and Fourier transform infrared (FT-IR) reflection spectroscopy. The structure and morphology of the surface layer were observed by FT-Raman spectroscopy, BET, and scanning electron microscopy (SEM). It was found that the bioactivity increased with decreasing PDMS content and increasing CaO content. Also, an increase in P₂O₅ concentration from 0 to 3 mol % decreased the induction period for apatite formation. A further increase in P₂O₅ content, however, increased the induction period. It was also noted that an increase in the P₂O₅ concentration from 0 to 3 mol % increased the surface area and micropore area and volume and decreased the pore diameter. On the other hand, the opposite trends were observed with a further increase in the P₂O₅ concentration. Among the various ormosil samples prepared with different compositions, the highest bioactivity was obtained from the ormosil with the composition of 20 wt % PDMS [PDMS/(TEOS + PDMS)], 15 mol % CaO [(Ca(NO₃)₂/TEOS) mole ratio], 3 mol % P₂O₅ [TEP/TEOS mole ratio].Original English Text Copyright © 2005 by Fizika i Khimiya Stekla, Whang, Seo, Oh, Kim.This article was submitted by the authors in English.     

Rigorous Computation of Binary Distillation Systems

Abstract

A computation algorithm for the distillation of binary systems based on the concepts involved in the graphical Ponchon—Savarit method is introduced. Equilibrium and enthalpy data are estimated by the UNIQUAC activity coefficient equation. All the parameters of the system (temperatures, enthalpies, flow rates, and composition of the streams in each stage) are computed with much higher accuracies than those obtained by the graphical method.     

溶胶-凝胶法制备锆/有机硅复合薄膜

以氧氯化锆(ZrOCl2·8H2O)和γ-氨丙基三乙氧基硅烷(KH-550)为先驱体,采用溶胶-凝胶法通过共缩聚反应在聚碳酸酯(PC)板表面制备了锆/有机硅复合薄膜,采用TG/DTA、FTIR、UV-VIS、金相显微镜及铅笔硬度测试方法对复合薄膜的结构及性能进行表征.研究结果表明,通过共缩聚反应,PC板表面形成带有机基团的无机交联网络结构,基本骨架由Si-O-Si,Si-O-Zr,Zr-O-Zr组成;当KH-550与氧氯化锆的物质的量比不低于2∶1时,涂膜PC板的透过率较高,表面较平整;去离子水对薄膜性能的影响较小,水与氧氯化锆的用量在80∶1～20∶1内均可以.PC板镀膜后硬度也由2B提高到H,膜层与基体的结合较好,不易脱落.     

无水溶胶-凝胶法制备有机-无机杂化光波导薄膜

以二苯基二羟基硅烷(diphenylsilanediol,DPSD)和γ-甲基丙烯酰氧基丙基三甲氧摹硅烷(γ-Methacryloxypropyl trimethoxy silane,MAPTMS)为前驱体,用无水溶胶-凝胶法合成出有机-无机杂化材料,将其旋涂在硅基片和石英玻璃片上得到杂化光波导薄膜.利用Abbe折射仪...     

Dielectric Bodies in Metal Stannate-Barium Titanate Binary Systems

Ceramic and dielectric properties of bodies in the binary systems of barium titanate plus the stannates of magnesium, lead, bismuth, zinc, nickel, copper, cadmium, cobalt, manganese, and iron have been investigated. Bodies in the system tin oxide-barium titanate also have been evaluated. Additions of tin oxide, lead stannate, cadmium stannate, zinc stannate, and copper stannate progressively decrease the Curie temperature of the body. Lead stannate bodies exhibit somewhat flatter peaks than the others and show much less variation of dielectric constant with temperature than do similar bodies prepared with the stannates of barium, calcium, or strontium. Additions of magnesium stannate, bismuth stannate, and nickel stannate greatly depress the Curie peak of barium titanate bodies. Bismuth stannate is particularly effective in producing bodies with very low temperature coefficient of dielectric constant. Bodies having dielectric constants of 4000 to 5000 (+25%, −50% from −60° to 85°C.) may be obtained from compositions containing about 15 mole % PbSnO₃. Bodies having dielectric constants of 2000 to 2300 (+ 10%, −40% from −60° to 85°C.) may be obtained from compositions containing about 4 or 5 mole% of either MgSnO₃or NiSnO₃. Bodies having dielectric constants of 1000 to 1200 (−4% from −60° to 85°C.) may be obtained from compositions containing about 5 mole % Bi₂(SnO₃)₃. Limited data indicate that the aging of various compositions apparently increases with level of dielectric constant. Non-linearity with d.-c. bias is greatest for high peak-K bodies. Up to the limits investigated, additions of CaSnO₃, PbSnO₃, MgSn0₃, and Bi₂ (SnO₃)₃ are absorbed in BaTiO₃ bodies as solid-solution-type simple cubic structures with slightly expanded lattices.     

Analyses of Multiple Film Cracking in Film/Substrate Systems

Multiple film cracking in a film/substrate system is analyzed in the present study. The system is subjected to residual stresses before loading. A constant displacement rate is applied unidirectionally to stretch the system. An analytical model is developed to derive the stress distribution in the system, and the film-cracking problem is analyzed using both the strength and the energy criteria. The predicted crack spacing as a function of the applied strain is compared with experimental measurements of multiple cracking of SiO _x films with various thicknesses on poly(ethylene terephthalate) substrates. Comparison is also made between the present and other predictions.     

水性漆的成膜

讨论了水乳型单组分水性漆成膜过程的特殊性及各种因素对漆膜性能的影响。     

溶胶──凝胶陶瓷薄膜制备工艺技术的研究

从溶胶制备和薄膜涂覆工艺两方面对溶胶──凝胶法制备陶瓷薄膜中的工艺技术进行了研究,并指出了溶胶──凝胶技术中存在的一些问题。     

溶胶-凝胶法制备锐钛矿型TiO2薄膜

本文以钛酸异丙酯为原料,采用溶胶凝胶法制备TiO2薄膜,通过DTA－TG、XRD、SEM探讨了材料的制备过程,相组成及显微结构,结果表明薄膜表面无微开裂现象,膜内部比表面积大,TiO2颗粒分布均匀,用溶胶－凝胶法可制得相组成为锐钛矿的均匀的TiO2薄膜。     

溶胶—凝胶陶瓷薄膜制备工艺技术的研究

本文从溶胶制备和薄膜涂覆工艺两方面对溶胶－凝胶法制备陶瓷薄膜中的工艺技术进行了研究,并指出了溶胶－凝胶技术中存在的一些问题。     

Solvent Extraction of Weak Acids in Binary Extractant Systems

The interphase distribution of weak acids in systems involving salts of quaternary ammonium bases with organic acids (binary extractants) has been analyzed. Significant differences in the extraction depending on the composition of the aqueous and organic phases for weak acids compared with that for strong acids in binary extractant systems have been shown. The difference in the extraction of weak acids with binary extractants compared with neutral extractants has been also revealed. The experimental data were interpreted by two variants of distribution processes, when two extracted species are formed (R₄NX and HA) and for the case of forming extracted species with strong H-bonds (R₄NX · HA). The least square regression method showed that the proposed mechanisms well describe the extraction of monocarboxylic acids with the binary extractant (the smallest sum of squares of relative deviations was 0.025) at their low initial concentrations (<0.05 mol · L^?1). It was shown that the most effective extraction of monocarboxylic acids takes place from acidic solutions (at pH < 2) that indicates the possibility of their effective stripping from organic solutions with water.