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171.
卢旭东  姜承志 《辽宁化工》2002,31(4):139-140
以钛酸四丁酯等为原料,采用简单工艺制得多孔TiO2陶瓷光催化剂;并研究了利用多孔TiO2陶瓷光催化降解糠醛废水。结果表明,在紫外灯下照射60min,糖醛废水的COD去除率可达59.8%,而通入空气有利于污染物的去除。  相似文献   
172.
This study presents a different colloidal silver (Ag)/polymer system where Ag nanoparticles are deposited uniformly onto surface-functional porous poly(ethylene glycol dimethacrylate-co-acrylonitrile) (poly(EGDMA-co-AN)) microspheres. The formation and morphology of the composite microspheres were characterized from electron microscopy and X-ray diffraction analyses. The significance of the present report is that owing to the high affinity between Ag and nitrile group (CN) on the large surface of the microspheres, the Ag nanoparticles having a face-centered cubic phase were incorporated evenly into the deep pores of the microspheres with fine size and size distribution. In the preservation test, the Ag/poly(EGDMA-co-AN) composite microspheres obtained showed an excellent anti-bacterial performance, elucidating a high applicability for a new preservative.  相似文献   
173.
莫来石及多孔莫来石的研究和应用   总被引:7,自引:1,他引:7  
高温性能稳定,抗热震性能好的莫来石是一种重要的工程陶瓷材料。概述了莫来石的结构、性能,以及在工业上的应用,并对多孔莫来石陶瓷的研究进展和应用进行了介绍。针对莫来石室温力学性能较差的缺陷,讨论了氧化锆和颗粒增韧莫来石的方法。最后,对多孔ZTM陶瓷发展前景进行了展望。  相似文献   
174.
拙、粗、土常指物品样式的俗气以及工艺的糙劣,也是民间陶瓷带给观者的视觉感受,而换个角度理解以上的描述还可以转换为另外层面的意思:如拙是巧拙、粗是自然、土为淳朴等,本文正是从此方面来阐释它们所赋有的美以及同当下人们内心感情的关联:它们表现了存留于人们内心的某种愿想:回归自然、返朴归真。  相似文献   
175.
邹东利  郭亚昆  路学成 《陶瓷》2007,(10):11-15
综述了纳米陶瓷和纳米复相陶瓷的的研究现状.探讨了纳米陶瓷的力学性能及其热喷涂纳米陶瓷涂层存在的问题.分析了纳米复相陶瓷的增韧机理,为纳米陶瓷的研究和应用提供了理论依据。  相似文献   
176.
杨萍 《江苏陶瓷》1997,30(1):6-8
研究了几种玻化砖用陶瓷颜料,确定其制备工艺和化学组成,并讨论这些颜料的特点,生产中应注意的问题及颜料用于玻化砖的使用量,并分析呈色的机理和结构特点。  相似文献   
177.
开发出一种新型微孔介质塔板—泡沫镍塔板 ,并在一个 5 0 0× 5 0 0mm2 有机玻璃方塔内用空气—水系统测定了其流体力学性能指标—塔板压降等 ,用二氧化碳解吸实验测定了塔板效率 ,研究了它们随空塔动能因子、堰高和液流强度变化的规律。实验结果表明 ,此种塔板虽然压降稍大 ,但传质效率很高且没有漏液 ,可用于工业生产中。  相似文献   
178.
Sacrificial template technique is widely used in producing porous materials with controlled morphologies and tailored properties. In this paper, unique templates such as filters, carbon nanotube, carbon fiber and silica were used to make porous SiC ceramic with special morphologies. Template derived porous ceramic plates, SiC nano-net, fiber-inverse and bead-inverse porous SiC ceramic were successfully prepared from the preceramic precursor, polymethylsilane (PMS). The synthesis procedures were involved with the infiltration of the templates with appropriate concentration of the preceramic polymer, their curing, pyrolysis and subsequent template removal. The synthesized porous SiC was characterized by SEM, TEM, XRD and BET methods.  相似文献   
179.
Summary In this work we present an experimental study of flow-induced degradation of hydrolyzed polyacrylamide in aqueous solutions flowing through porous media. The degradation is analyzed by passing the solution repeatedly through the medium at a constant flow velocity and the degraded solution is then characterized by porous media and opposed jets flows. When the polyacrylamide is dissolved in deionized water, it exhibits a gradual extension thickening in the flow through porous media and opposed jets. In this case, the polymer degrades as it passes through the porous medium even at relatively low flow rates. When the polyacrylamide is dissolved in an NaCl solution, it exhibits critical extension thickening in porous media flows, and it only degrades at Reynolds numbers that are higher than the onset of the extension thickening behavior. Chain degradation is therefore only encountered when extension thickening is produced. The results also show that the extent of degradation decreases as the pore size decreases.  相似文献   
180.
Fluid flow in coupled free and porous domain, particularly when the porous medium is heterogeneous, is encountered in many hydro-environmental conditions, e.g., leakage from underground pipe, combined groundwater lake-subsurface interactions. One of the most difficult problems in the study of coupled flow behaviour has been the development of a universally applicable modelling scheme for combining the flow regimes. This is because the free/porous interfacial properties (e.g., shear-stress; velocity slip) that govern the coupled flow behaviour are difficult to determine experimentally under hydro-environmental conditions. On the other hand, the implications of various forms of heterogeneity in the porous media properties can be very different on the fluid-flow behaviour. Difficulties may also arise in direct coupling of the model equations that govern the fluid flow in the individual regions (e.g., Navier-Stokes for free-flow region and the Darcy's equation for the porous flow region). Consequently, models of coupled free and porous flow for hydro-environmental conditions are not very well developed at the moment. While there are some indications that fluids in coupled free and porous domains may circulate (i.e., development of flow cells), there is a lack of appropriate 3D analysis on how heterogeneities in porous media may affect such flow patterns. In this paper, we aim to analyse how porous media heterogeneity affects the dynamics of flow circulation in the porous side of a coupled free and porous domain. For this purpose, we analyse flow patterns in several model domains made up of two porous layers with differing permeabilities. The governing model equations are discretised and solved using the standard finite volume method on a staggered cell-centred mesh. The temporal discretisation is done using the explicit method. An in-house graphical user interface (GUI) has been created specifically to aid in the visualisation of otherwise complex flow patterns. The GUI contains many post-processing options and provides a comprehensive tool for the analysis of hydrodynamics and contaminant motion (not discussed in this paper) in coupled free and porous flow domains. This GUI is described in this paper briefly. The effects of altering the aspect ratio (i.e., multi-scale) of the domain on the coupled flow pattern have also been discussed.  相似文献   
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