多孔材料气体流量的简便计算

采用简便方法计算气体通过多孔材料的流量。当层流时，流量与压差按线性关系计算；紊流时，应按幂函数关系计算。本文提出了计算公式。     

Application of Acoustic Wave Propagation Analysis Methods for Monitoring a Miscible Mixing Zone in Porous Media

The Biot's acoustics theory, which describes acoustic wave propagation in a porous medium, and computer simulation techniques were utilized to model the behavior of acoustic waves entering and leaving a mixing zone in a miscible displacement in porous media. The results indicate that the angles of waves produced by a mixing zone are equal to angles of waves produced by an abrupt fluid-fluid interface. Therefore, acoustic methods and a relationship between the incident, reflection, and transmission angles can be used to determine the location and thickness of the mixing zone during a miscible displacement process in porous media.     

Gasification reactivity of charcoal with CO2. Part I: Conversion and structural phenomena

The gasification reaction of fir charcoal with CO₂ was studied by isothermal thermogravimetric analysis under kinetic control. The derived reaction rate (r=dX/dt) as a function of the converted carbon mass (X) was compared with random pore model predictions and found to be much higher at elevated conversion levels than predicted by theory. Similar enhanced reaction rate behaviour was evidenced after removing the natural alkali catalyst from the charcoal by acid washing, suggesting that with untreated charcoal the late reaction rate contribution stems from both, catalytic and additional structure effects. Literature attributes the unpredicted late reaction rate behaviour to the disintegration of the porous char particle into small fragments, which, in line with percolation theory predictions, seems to occur only after a critical conversion level has been reached. However, our gasification data reveal a gradual rise in the charcoal reactivity thereafter, suggesting a breaking up (embrittlement) of the solid phase accompanied by the exposure of fresh surface area from fracturing. The original random pore model derivation given by Bhatia and Perlmutter is extended to account also for these peculiarities and the resulting kinetic relation described our reaction rate data well over the entire conversion range.     

Optimized Schwarz methods without overlap for highly heterogeneous media

In this paper an original variant of the Schwarz domain decomposition method is introduced for heterogeneous media. This method uses new optimized interface conditions specially designed to take into account the heterogeneity between the sub-domains on each sides of the interfaces. Numerical experiments illustrate the dependency of the proposed method with respect to several parameters, and confirm the robustness and efficiency of this method based on such optimized interface conditions. Several mesh partitions taking into account multiple cross points are considered in these experiments.     

Mortar finite element discretization for the flow in a nonhomogeneous porous medium

Darcy’s equations model the flow of a viscous incompressible fluid in a rigid porous medium. One of the parameters of the system depends on the permeability of the medium and, when this medium is not homogeneous, the variations of the parameter could be very high. To handle this phenomenon, we propose a discretization of the model that relies on the mortar finite element method. Indeed, the idea is to construct a decomposition of the domain such that the permeability is constant on each element of the partition and to use independent meshes on the different subdomains. We perform the a priori and a posteriori analysis of this discretization and present some numerical experiments which are in good coherency with the results of the analysis.     

植物油、脂肪酸和植物油甲酯在塔河稠油掺稀降黏中的应用评价

稠油由于富含沥青质、胶质等重质组分而具有很高的黏度，给稠油的开采和运输带来了很大的困难。降低稠油黏度进而改善其流动性成为一项十分重要的工作。以植物油、脂肪酸及植物油甲酯为掺稀介质，以塔河油田稠油为研究对象，考察对比了3种不同的掺稀介质对稠油的掺稀降黏效果。研究结果表明，3种掺稀介质对稠油具有良好的掺稀降黏效果，在同一掺稀比下，植物油甲酯对稠油的降黏效果最显著，其次是脂肪酸，再次是植物油。通过斑点试验考察了掺稀介质和稠油的相容性和体系稳定性。结果显示，植物油甲酯与稠油相容性和稳定性最好，脂肪酸和植物油与稠油的相容性和稳定性相对较差。     

鼠笼式搅拌磨的流体场建模及计算机仿真

搅拌磨机在工业与研究领域是一种效率高的超细粉磨设备。为了优化设计参数，提高鼠笼式搅拌磨机的粉碎效果，需要对磨机研磨室内的流体场作深入的研究。利用Ansys有限元软件对鼠 式搅拌磨机研磨室的圆截面内的流体场进行仿真分析。通过对仿真结果的分析可知，在该流体场内存在着2个速度梯度较高的区域。在这2个区域中，粉碎作用明显。为了得到最佳的粉碎效果，应该使磨球尽可能地通过这2个区域。     

供水水源及管线分布式微机网络系统

本文介绍了一种由ＡＴ３８６为主机，６台ＱＡＴ２８６和最多可增加到２５６台ＭＣＳ－５１单片机系统为从机，采用两种通讯介质（２０ｍＡ电流环和无线电）所组成的分布式微机网络系统。并介绍了该系统的结构设计和软件研制。     

Solid-state NMR as a probe of porous catalysts and catalytic processes

The power of solid-state NMR for the interrogation of porous catalytic materials is illustrated using three examples. First, for the investigation of catalytic processes occurring within the confines of a microporous catalyst NMR is shown to reveal both the details of shape-selectivity and the nature of internal surface species. Second, NMR is shown to be a powerful short-range tool to reveal precise structural information on highly disordered microporous titanosilicates. Despite long-range disorder the short-range order is maintained and can be easily studied. Finally, the same utility of probing short-range chemical phenomena is shown to be crucial for the investigation of novel-ordered-amorphous-mesoporous materials known generically as M41S. This class of material is currently one of the most important with potential catalytic application.     

IPTV及相关技术

IPTV是基于IP协议的新一代技术,介绍了IPTV的主要业务功能和系统组成,并阐述了IPTV系统的关键技术。