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91.
On the use of graphical method to determine the targets of single-contaminant regeneration recycling water systems 总被引:2,自引:0,他引:2
Water system integration with regeneration recycling can reduce freshwater consumption and wastewater discharge to the maximum extent. In this paper, by analyzing the limiting composite curve of a single-contaminant water system, a method is proposed to construct the optimal water supply line for regeneration recycling. Accordingly the targets for regeneration recycling water systems are obtained. The targets in sequence are the minimum freshwater consumption (the minimum wastewater discharge), the minimum regenerated water flowrate, and the optimal regeneration concentration. The post-regeneration concentration is taken to be fixed in the sequential targeting procedure. The interactions of these targets are analyzed, and formulas for calculating these targets are proposed. The results show that for a single-contaminant regeneration recycling water system, the minimum freshwater consumption is determined by the shape of the limiting composite curve below the post-regeneration concentration. The optimal regeneration concentration is defined as the minimum regeneration concentration at the minimum freshwater consumption and the corresponding minimum regenerated water flowrate. The minimum regenerated water flowrate and the optimal regeneration concentration are both related to the geometrical features of the limiting composite curve of the water-using system and to the post-regeneration concentration. The optimal regeneration concentration has no direct relationship with the pinch concentration. 相似文献
92.
93.
A novel redox system, potassium diperiodatonickelate (Ni(IV))‐casein is used to initiate graft copolymerization of Styrene onto casein under different conditions in aqueous alkaline solution. Graft copolymers with both high grafting efficiency (>98%) and percentage of grafting(>300%) are obtained, which indicated that (Ni(IV))‐casein redox pair is an efficient initiator for this grafting. The effects of reaction parameters, such as monomer‐to‐casein weight ratio, initiator concentration, pH, time, and temperature, are investigated. A tentative initiation mechanism is proposed. The structures and properties of the graft copolymer are characterized by Fourier transform infrared Spectroscopy, X‐ray diffraction diagrams, and Scanning Electron Microscope. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4247–4251, 2006 相似文献
94.
It has been shown in a previous paper in this series that important dilatation is produced by plastic deformation under tension of neat PP and PP/PA6/POE blends, for which the POE to PA6 concentration ratio equals 1/2. In this work, the detailed mechanisms of this volume change are investigated from electron micrographs (SEM and TEM) obtained in the deformed state. At low alloy content, it is thus observed that dilatation results from decohesion of the PA6 particles from the PP matrix. As the amount of PA6 and POE increases, voids are nucleated preferentially in the thicker POE interphase making a shell around the PA6 particles, and secondarily in isolated POE particles. Unexpectedly, it has been found that the overall volume dilatation decreases with total alloying content. This is interpreted by: (i) the increasing contribution of PA6 that intrinsically deforms with less cavitation than PP, (ii) the post-cavitation rubber-like stretching of POE particles and, (iii) the early formation of a percolating network of shear bands from the diffuse array of voids formed after the yield point. These mechanisms explain the gradual increase of the resistance to impact of the PP/PA6/POE as their alloying content is increased. 相似文献
95.
本文首先介绍了VoIP技术的研究和发展方向,通过分析VoIP的核心协议——SIP协议的安全问题和研究现状,说明VoIP安全性能的研究内容和现实意义,最后给出了本研究的发展方向。 相似文献
96.
Yue-long Bai) Jun Xu) Zhi-feng Zhang) Wei-min Mao) Hong Xu) ) General Research Institute for Non-ferrous Metals Beijing China ) School of Materials Science Engineering University of Science Technology Beijing Beijing China ) Research Center for Foundry Engineering North University of China Taiyuan China 《北京科技大学学报(英文版)》2009,16(4):422-426
The effect of injection pressure, piston velocity, and the forming temperature of semisolid slurry on the filling behavior of the semi-solid A356 aluminum alloy was investigated by simulation methods. The simulation results show that these processing parameters have an important effect on the filling behavior of the semi-solid A356 aluminum alloy. The slurry flows steadily in the cavity when the injection pressure, the piston velocity, and the forming temperature are low, but it is prone to turbulent flow w... 相似文献
97.
针对我国职业危害形势的严峻性及我国现阶段职业危害防治研发基地和支撑条件案件相对落后的实际,提出建设国家职业危害实验基地。通过国内外调研,根据初步规划研究将建立职业危害检测与鉴定、放射卫生防护检测与评价、生物监测、工业通风研究、减振防噪研究、人类工效学研究、劳动防护用品检测与研发等七个研究中心,组成职业危害检测与评价和职业卫生工程两个研究平台,为提高我国职业危害的防治水平打下基础。 相似文献
98.
一种组态式产品设计方法 总被引:1,自引:0,他引:1
为了实现产品的快速定制和设计知识的重用,以进一步提高设计效率,促进产品配置的智能化,在模块化的基础上,文章提出了一种组态式的产品设计方法。对组件、组态概念进行了界定;对组件化方法、组态过程进行了阐述;并给出了组态系统的方程。最后,以某工装夹具的组件化和组态过程为例,详细说明了组态设计的基本原理和方法。 相似文献
99.
Bubble collecting, bubble holding and micro-bubble ejecting characteristics of pit structure and the influence of cavitation
bubble on the development of erosion pit are investigated by means of high-speed photography experiments. Pits tend to collect
and hold wandering cavitation bubbles. The air holding phenomenon of pits can be a destination of the incubation period in
the process of cavitation erosion. The holding bubble tends to eject micro-bubbles from the top of holding cavitation bubble,
making the pit a source of nuclei. With bubbles being held in pits, the diameters of pits increase rapidly. But in the given
experiment condition, there is a specific stable value beyond which the diameter of pits will not increase. This characteristic
will be helpful in understanding and predicting the cavitation erosion process.
Supported by the National Basic Research Program of China (“973” Program) (Grant No. 2007CB714105) and the National Natural
Science Foundation of China (Grant No. 50539060) 相似文献
100.
环形橡胶径向刚度特性仿真分析 总被引:1,自引:0,他引:1
利用ANSYS软件建立了环形橡胶的有限元参数化模型,将对模型仿真所得结果与已有数据进行对比,验证了仿真模型的正确性,实现了环形橡胶径向刚度的快速计算.在此基础上,分析了内外圆柱面半径与轴向长度对环形橡胶简化径向刚度值的影响,研究了环形橡胶的径向刚度特性,确立了在环形橡胶实际设计中需要考虑的要点,为环形橡胶的设计提供了依据. 相似文献