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111.
用区域烧结在1 d内可完成高温气体清洁用1.5 m陶瓷过滤管的制备过程,区域烧结的优势是缩短研究和开发周期.目前,经过认真设计,已经完成区域烧结设备.多孔陶瓷件比致密陶瓷件更容易烧结成型,原因是多孔陶瓷在区域烧结期间可免除其收缩和变形.  相似文献   
112.
微孔陶瓷材料在水处理中的应用   总被引:2,自引:0,他引:2  
马晓雁  戴长虹  吴会中 《中国陶瓷》2003,39(6):46-48,51
本文从微孔陶瓷的结构特性出发,分析了微孔陶瓷作为过滤介质在水处理除杂净化过程中的过滤机理,论述了微孔陶瓷在饮用水净化处理和某些工业废水、生活污水处理中的应用。  相似文献   
113.
The paper deals with state estimation of the nonlinear stochastic systems by means of the unscented Kalman filter with a focus on specification of the σσ-points. Their position is influenced by two design parameters—the scaling parameter determining the spread of the σσ-points and a covariance matrix decomposition determining rotation of the σσ-points. In this paper, a choice of the scaling parameter is analyzed. It is shown that considering other values than the standard choice may lead to increased quality of the estimate, especially if the scaling parameter is adapted. Several different criteria for the adaptation are proposed and techniques to reduce computational costs of the adaptation are developed. The proposed algorithm of the unscented Kalman filter with advanced adaptation of the scaling parameter is illustrated in a numerical example.  相似文献   
114.
115.
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   
116.
Schaefer-Sindlinger  A.  Lappas  I.  Vogt  C. D.  Ito  T.  Kurachi  H.  Makino  M.  Takahashi  A. 《Topics in Catalysis》2007,42(1-4):307-317
This paper will give an overview about the filter development for diesel particulate emission control in automotive applications. The material development for passenger car diesel particulate filters led to new materials like silicon carbide while for heavy duty applications still Cordierite plays a major role. But in the future other materials might also be used for passenger cars. This paper will show the basic difference between both applications and describe the material design in terms of filter properties (base material, back pressure aspects, filtration efficiency, coating impact). Current application on vehicles with catalysed soot filters (CSF) with and without oxidation catalyst will be presented. Furthermore an outlook will be given on materials for catalysed soot filters for the future.  相似文献   
117.
珍珠岩助滤剂在天然卤水精制中的应用   总被引:2,自引:0,他引:2  
通过实验 ,得出在天然卤水制小苏打的生产过程中 ,使用珍珠岩助滤剂对天然卤水精制是可行的。  相似文献   
118.
工业污水深度处理回用技术研究   总被引:2,自引:0,他引:2  
刘振龙 《乙烯工业》2005,17(2):60-62
通过对石化企业工业污水进行曝气生物滤池、连续微滤、反渗透等深度处理,使出水满足工业化用水的水质要求,从而得以回用。  相似文献   
119.
The applicability of a newly developed radiotracer technique as a reliable laboratory procedure for the evaluation of scale inhibitors performance to prevent mineral precipitation is demonstrated. The performance of two new environmentally friendly inhibitors to prevent calcite and barite scale was evaluated experimentally in connection with a standard phosphonate-type scale inhibitor using the radioactive tracer technology. The radiotracers 47Ca and 131Ba were employed in order to monitor at real-time calcite and barite scale formation, respectively. The results show that the developed radiotracer technique can be established as a novel method for the determination of the minimum inhibitor concentration (MIC) under dynamic, reservoir conditions. In addition, the radioactive tritiated water (HTO) was used as a reference water tracer to identify the inhibitors’ properties, such as adsorption/desorption characteristics, in sandpack-flooding tests. Further issues regarding the implementation of the radiotracer technology for the laboratory evaluation of scale inhibitors performance are also discussed.  相似文献   
120.
A new explicit numerical simulation (ENS) method based on lattice-gas automata (LGA) is introduced here for the flow of solid/fluid suspensions with deposition in porous media. The ENS method explicitly resolves the dynamics of the individual solid particles and the suspending fluid in the domain defined by the pore walls and solid particle surfaces. After describing the new method, it is applied to the study of solid/fluid suspension flow with deposition in a constriction and in a model random porous solid. This study clearly demonstrates that the deposits strongly influence the local flow fields, which in turn affect the deposition process indicating that this interplay should be modelled if accurate results are desired from trajectory methods.  相似文献   
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