Characterization and Electrophoretic Deposition of Poly(Phenylsilsesquioxane)–Titania Hybrid Particles Prepared by the Sol–Gel Method

Poly(phenylsilsesquioxane)–titania (PhSiO_3/2–TiO₂) hybrid particles were prepared from phenyltriethoxysilane and titanium tetra- n -butoxide by the sol–gel method. Fourier transform infrared spectra showed that PhSiO_3/2 and the TiO₂ components were hybridized through Si–O–Ti bonds. The refractive index of the particles was monotonically increased from 1.57 to 1.62 with an increase in the TiO₂ content. The PhSiO_3/2–TiO₂ particles were electrophoretically deposited on indium tin oxide (ITO)-coated glass substrates to form opaque, thick films about 3 μm in thickness. When the mole ratio x in (1− x )PhSiO_3/2· x TiO₂ was equal to or less than 0.05, the deposited PhSiO_3/2–TiO₂ films became transparent with a heat treatment at 400°C because of the thermal sintering of the particles.     

片状模板对电泳沉积制备织构化氧化铝的影响

本文研究不同片状氧化铝模板含量和形态对电泳沉积方法制备织构化氧化铝陶瓷的影响.结果表明,不同形态片状模板的加入都会使氧化铝的密度下降,并且模板含量增加越多,密度下降也越大.在加入量超过6％后能制备出具有一定取向的氧化铝陶瓷,但加入量进一步提高时,由于堆积密度的下降,晶粒尺寸也有所下降.不同形态的片状模板对织构化形成的影响较大,径厚比越低的模板越有利于致密化的提高,但是径厚比较大的模板更有利于织构化结构的形成.     

Preparation of Tubular Silicalite Membranes by Hydrothermal Synthesis with Electrophoretic Deposition as a Seeding Technique

Preparation of tubular silicalite membranes by hydrothermal synthesis with electrophoretic deposition (EPD) as a seeding technique was investigated. Two micrometers of small silicalite seeds were produced by an open-system hydrothermal synthesis at 100°C. These seeds were dispersed in 1-propanol and seeded on porous tubular stainless-steel supports by EPD; it had a high productivity and uniformity. The seeded support was then hydrothermally treated, and a tubular silicalite membrane was obtained. The pervaporation performance of this membrane showed a separation factor α of 70 with a total flux of 0.35 kg·(m²·h)⁻¹ for a 5 vol% EtOH aqueous solution at 30°C.     

用溶剂萃取法从ITO膜蚀刻废液中回收金属铟的实验研究

文章对ITO膜蚀刻废液中锱的回收进行了研究。首先采用TBP萃取蚀刻废液,在实验的最优条件下经两次萃取,钢的萃取率可达到96.2％。然后用水反萃TBP有机相,不仅反萃了金属铟,并实现了铟、锡分离。使用P2O4对反萃液萃取及盐酸反萃富集,所得的富钢溶液由NaOH调节pH,用铝片置换,成功回收海绵钢。     

Preparation of a Superhydrophobic ZnO Film on ITO Glass via Electrodeposition Followed by Oxidation. Effect of the Deposition Time

This study investigates the fabrication of a stable superhydrophobic surface with low contact angle (CA) hysteresis using ZnO thin films prepared by cathodic electrodeposition and subsequent gaseous oxidation. The deposition time is a crucial factor in nanostructuring and producing surface roughness of the films. Cathodic electrodeposition for 60 s created a number of nanopillars, which exhibited the highest CA value, i.e., 167.9°. The rough ZnO surface displayed not only enhanced water repellency with low CA hysteresis but also excellent superhydrophobic stability. The application of the Cassie–Baxter model demonstrated that the ZnO nanostructure contributed to increasing the area of a water droplet in contact with air, leading to superhydrophobicity. Such a unique textured surface showed a great potential for the engineering of strong superhydrophobic coatings.     

Microstructure and Anisotropic Properties of Textured ZrB2 and ZrB2–MoSi2 Ceramics Prepared by Strong Magnetic Field Alignment

Dense, highly textured ZrB₂ and ZrB₂–MoSi₂ ceramics were fabricated via a strong magnetic field alignment method followed by spark plasma sintering. Unlike with the previous studies, which only focused on the alignment of single‐phase particles, both ZrB₂ and MoSi₂, which exhibited a magnetic anisotropy, have been aligned in this study. The alignment of MoSi₂ in the same direction of ZrB₂ enhanced the degree of orientation of ZrB₂, decreased the grain size, but increased the aspect ratio of the platelet ZrB₂ grains. The microstructure and anisotropic mechanical properties as well as the oxidation resistance in different directions were discussed.     

磁场下电沉积制备Co-W合金镀层

在磁场下电沉积制备Co-W合金镀层,研究了磁场强度对镀层沉积速率、微观形貌、成分以及磁性能等的影响.结果表明:沉积速率随着磁场强度的增大而显著提高;洛伦兹力可以降低电极表面的浓差极化,避免氢气的析出,使镀层均匀、致密;随着磁场强度的增大,镀层的比饱和磁化强度逐渐增大,而矫顽力呈先增大后减小的趋势,当磁场强度为0.5T时,矫顽力最大.     

Preparation of Bi-Sr-Ca-Cu-O Thin Films by Sputtering under a Variable Magnetic Field

Bi-Sr-Ca-Cu-O thin films were deposited on MgO(100) substrates by a new sputtering method which controls the film composition with magnetic fields over the target. Films having compositions close to Bi₂Sr₂Ca₂Cu₃O_x were annealed at 880°C to show superconductivity at moderately high T_c's. Auger electron spectroscopy indicated a chemical interaction between the film and the substrate during the annealing, and this information was utilized to improve the annealing conditions.     

Triaxial Crystalline Orientation of MgTi2O5 Achieved Using a Strong Magnetic Field and Geometric Effect

Tailoring the crystallographic orientation in ceramics is very useful for improving their properties. We reported that the colloidal processing in a strong magnetic field was able to control the crystallographic orientation even in diamagnetic ceramics. In this process, a strong magnetic field is applied to the particles in a stable suspension. The orientation of the crystal depends on the axis having easy magnetization and one‐dimensional orientation can be controlled. In this study, our concept is that control of multiaxial crystalline orientation in ceramics by using both anisometric particles and a magnetic field. The control of the triaxial orientation was achieved by tape casting of rod‐like MgTi₂O₅ particle in a magnetic field. The b‐axis was aligned by the magnetic field, and the a‐axis was aligned by the geometric effect and shear stress during tape casting.     

磁场作用下冷冻铸造法制备仿生材料研究进展

随着科技的迅速发展,对材料的性能提出了更高的要求,迫切需要开发新型轻质高性能结构材料,即低密度、高刚度、高强度和高韧性等特点集于一身.生物材料经过数亿年的进化,形成了与环境和功能需求相适应的精细复杂结构,如贝壳珍珠层的砖-泥结构和螃蟹角质层的螺旋结构,它们均表现出非凡的机械性能和独特的功能特性,这启发了人们对于高性...     

催化氨氧化制备丁酮肟催化剂循环利用

以钛硅分子筛(TS-1)作催化剂,丁酮为原料,经催化氨氧化一步合成了丁酮肟.小试实验考察了影响反应结果的因素,特别是对催化剂循环利用及溶剂选择问题进行了探讨.试验表明:在不接触空气或尽量不接触空气的情况下,催化剂循环利用4次,丁酮肟转化率及选择性未有明显下降;催化剂经焙烧后再循环使用,经试验3次,未发现明显失活.考虑到工业化应用的优势,试验以过量丁酮为溶剂代替叔丁醇,结果表明与叔丁醇作溶剂时相比,丁酮肟选择性有较明显降低.     

催化氨氧化制备丁酮肟催化剂循环利用及溶剂选择的探讨

以钛硅分子筛（TS-1）作催化剂,丁酮为原料,经催化氨氧化一步合成了丁酮肟。小试实验考察了影响反应结果的因素,特别是对催化剂循环利用及溶剂选择问题进行了探讨。试验表明：在不接触空气或尽量不接触空气的情况下,催化剂循环利用4次,丁酮肟转化率及选择性未有明显下降;催化剂经焙烧后再循环使用,经试验3次,未发现明显失活。考虑到工业化应用的优势,试验以过量丁酮为溶剂代替叔丁醇,结果表明与叔丁醇作溶剂时相比,丁酮肟选择性有较明显降低。     

Nucleation and Growth of Titania Nanoparticles Prepared by Pulsed Injection Metal Organic Chemical Vapor Deposition from a Single Molecular Precursor

Nanometer-sized titania particles were deposited by the pulsed liquid injection chemical vapor deposition technique from a single molecular metal-organic precursor. A liquid solution of titanium (IV) isopropoxide was used, Ar was the carrier gas, and titania nanoparticles were deposited on the hot wall of the reactor fused quartz tube, under supersaturated conditions. Energy-dispersive spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy studies reveal the formation of amorphous titania-agglomerated nanoparticles (40–50 nm). XRD patterns after different post-annealing processes reveal a high anatase–rutile transformation temperature, comparable to that of micrometer-sized titania, attributed to lattice strains in the nanoparticle structure, as calculated from the X-ray data. The growth dynamics involved in the nucleation and formation of titania nanoparticles is discussed in terms of the so-called chemical vapor synthesis or chemical vapor condensation.     

交变磁场下脉冲电沉积镍-钴纳米合金镀层

在脉冲电沉积镍-钴纳米合金镀层的过程中引入与电场方向垂直的外加交变磁场。采用扫描电镜和X射线衍射仪观察并分析镀层的表面形貌和微观结构,并用显微硬度计测试镀层的显微硬度。结果表明:外加交变磁场的引入可使镀层晶粒细化,镀层表面平整、致密,镀层的显微硬度呈先增大后减小的趋势。     

直流电场诱导下TeO2-Nb2O5-BaO-AgCl 系统玻璃的纳米晶析出研究

非线性光学玻璃材料在光电领域中具有广泛的应用前景,而纳米晶掺杂的非线性光学玻璃材料因其较高的三阶非线性效应已成为目前研究的热点。本文主要研究了直流电场诱导下TeO_2-Nb_2O_5-BaO-AgCl系统玻璃的纳米晶析出研究。研究结果表明,因BaO对铌碲酸盐玻璃系统链状网络结构的完善作用,能够较好地抑制TeO2、铌碲酸盐等与玻璃基体相关晶体的析出,使得TeO_2-Nb_2O_5-BaO-AgCl系统玻璃在适当的热处理条件下能够析出单一完整的AgCl晶体。同时,外加辅助电场能够促进铌碲酸盐系统玻璃的成核和晶化,并且能够较好地控制纳米晶体的析出,为今后制备高性能的纳米晶掺杂铌碲酸盐玻璃打下了良好的基础。     

Solvent effects in the hydrodechlorination of 2,4‐dichlorophenol over Pd/Al2O3

Solvent effects in the liquid phase (0.1 MPa; 303 K) hydrodechlorination (HDC) of 2,4‐dichlorophenol have been established over Pd/Al₂O₃. In the absence of secondary reactions, catalyst deactivation, and transport limitations, a stepwise HDC yields 2‐chlorophenol and phenol, where product selectivity was insensitive to the nature of the solvent. In contrast, the initial HDC rates exhibited a marked dependence on the reaction medium and increased in the order: benzene < THF < n‐hexane < cyclohexane < alcohols < water. Higher rates result from the concomitant effect of an increase in the dielectric constant (ε) and a decrease in the molar volume ( $\overline {\nu}$ ) of the solvent, where the major (ca. 80%) contribution is due to ε. We attribute this response to the increased solvent capacity to stabilize the arenium intermediate at higher/lower ε/$\overline {\nu}$ , an effect that extends to reaction in water + organic combinations. We provide, for the first time, a reliable quantification of solvent effects that can be potentially applied to other catalytic hydrogenolysis systems. © 2009 American Institute of Chemical Engineers AIChE J, 2010     

撞击流反应-沉淀法制取纳米二氧化钛影响因素的实验研究

采用浸没循环撞击流反应(SCISR),通过四氯化钛快速水解沉淀法制备了纳米二氧化钛,研究了浓度、温度、转速、中和时间、煅烧温度以及煅烧时间等因素对纳米二氧化钛粒径的影响。     

Micropatterning of Transparent Poly(Benzylsilsesquioxane) Thick Films Prepared by the Electrophoretic Sol–Gel Deposition Process Using a Hydrophobic–Hydrophilic-Patterned Surface

Poly(benzylsilsesquioxane) (BnSiO_3/2) particles show glass transition behavior, and the particles become a supercooled liquid when they are heated at temperatures above the glass transition temperature. Contact angles of BnSiO_3/2 molten liquid on the hydrophobic surface with fluoroalkylsilane and hydrophilic surface with silica were found to be around 77° and 12°, respectively. Using the difference in wettability for BnSiO_3/2 molten liquid between the hydrophobic and hydrophilic surfaces, micropatterns of transparent BnSiO_3/2-thick films were formed by the electrophoretic deposition of BnSiO_3/2 particles on indium tin oxide substrates with hydrophobic–hydrophilic patterns and subsequent heating above the glass transition temperature.