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301.
水污染预警DSS系统框架下的白河水质预警模型研究 总被引:3,自引:3,他引:3
为了应对频发的水环境污染事故,在污染事故发生后快速有效地制定应急响应措施,保护水环境,有必要在水源保护区建立水污染预警DSS系统,重点对系统建立的核心与难点——水质预警模型进行研究.密云水库是北京市最重要的地表水源地,以密云水库上游的白河为研究区域建立水污染预警DSS系统,设计水污染预警DSS系统的三层结构框架,将控制端、核心预警模型、GIS空间数据库紧密联合起来;在此基础上对核心预警模型的建模过程、参数取值等进行研究;最后以典型污染物氰化钠为例,设置水污染事故情景以及应急措施预案情景,进行了情景模拟分析.实例研究表明,此水质预警模型能够较准确地对污染发展趋势进行分析预测,并对不同的应急处理方案的实施效果进行模拟分析,模拟结果能够支持应急方案的制定与优选决策,达到了DSS系统的功能需求. 相似文献
302.
Ahmed Elsayed Raya K. AL-Dadah Saad Mahmoud Waseem Kaialy 《International Journal of Green Energy》2018,15(5):277-285
Commercially available adsorption cooling systems use water/silica gel, water/zeolite and ammonia/ chloride salts working pairs. The water-based pairs are limited to work above 0°C due to the water high freezing temperature, while ammonia has the disadvantage of being toxic. Ethanol is a promising refrigerant due to its low freezing point (161 K), nontoxicity, zero ozone depletion, and low global warming potential. Activated carbon (AC) is a porous material with high degree of porosity (500–3000 m2/g) that has been used in wide range of applications. Using Dynamic Vapour Sorption (DVS) test facility, this work characterizes the ethanol adsorption of eleven commercially available activated carbon materials for cooling at low temperature of ?15°C. DVS adsorption results show that Maxsorb has the best performance in terms of ethanol uptake and adsorption kinetics compared to the other tested materials. The Maxsorb/ethanol adsorption process has been numerically modeled using computational fluid dynamics (CFD) and simulation results are validated using the DVS experimental measurements. The validated CFD simulation of the adsorption process is used to predict the effects of adsorbent layer thickness and packing density on cycle uptake for evaporating temperature of ?15°C. Simulation results show that as the thickness of the Maxsorb adsorbent layer increases, its uptake decreases. As for the packing density, the amount of ethanol adsorbed per plate increases with the packing density reaching maximum at 750 kg/m3. This work shows the potential of using Maxsorb/ethanol in producing low temperature cooling down to ?15°C with specific cooling energy reaching 400 kJ/kg. 相似文献
303.
二氧化硫对大鼠肺泡细胞和肺泡灌洗液的生化效应 总被引:4,自引:1,他引:4
研究了二氧化硫(SO2)对大鼠支气管肺泡灌洗细胞和肺泡灌洗液(BALF)的生化指标的影响。结果表明,吸入SO2后大鼠BALF中肺泡巨噬细胞数量增加、但比例减少,中性粒细胞和淋巴细胞数量和比例均增加,并存在剂量一效应关系;熏气后BALF的pH下降、蛋白质含量和肺通透指数升高,BALF中酸性磷酸酶、碱性磷酸酶和乳酸脱氢酶活性升高,脂质过氧化水平提高:这些细胞和生物化学指标的改变从不同的方面反映了SO2可引起大鼠肺组织和肺泡细胞的结构和功能的损伤。 相似文献
304.
概述与分析了液膜分离技术,重点介绍了液膜法处理含酚废水、含(NH4)2S废水、含氰废水的工艺和方法. 相似文献
305.
Janusz A. Pudykiewicz Anna S. Koziol 《Atmospheric environment (Oxford, England : 1994)》1998,32(24):5541
The most common technique used for numerical simulations of tracer mixing is that of the numerical solution of the advection–diffusion equation with the unresolved fluxes parameterized using the similarity theory. Despite correct predictions of the overall directions of transport, models based on a numerical solution of the advection–diffusion equation lack sufficient accuracy to correctly reproduce the coupling of mixing with small scale processes which are sensitive to the microstructure of the tracer distribution. The objective of this paper is to revisit the basic formalism employed in numerical models used to investigate atmospheric tracers. The main mathematical method proposed here is the theory of kinematics of mixing which could be applied effectively for simulations of atmospheric transport processes. At the beginning of the paper, we introduce simple mathematical transformations in order to demonstrate how complex topological structures are created by mixing processes. These idealistic flow systems are essential to explain transport properties of much more complex three-dimensional geophysical flows. An example of the application of the kinematics of mixing to the analysis of tracer transport on a planetary scale is presented in the following sections. The complex filamentary structures simulated in the numerical experiment are evaluated using some commonly applied statistical measures in order to compare the results with the data published in the literature. The results of the experiment are also analysed with the help of simple conceptual models of fluid filaments. The microstructure of the tracer distribution introduced in the paper is essential to increase our understanding of atmospheric transport and to develop more realistic parameterizations of small-scale mixing. The presented results could also be used to improve calculations of the coupling between microphysical processes and tracer mixing. 相似文献
306.
Amniotic fluid from 72 pregnancies at risk for mucopolysaccharidosis have been analysed for glycosaminoglycans (GAG) by means of two-dimensional electrophoresis. Definite results were obtained in all cases and required only 3 days to report. Of the 66 cases for which GAG analysis was accompanied by enzyme assays on cultured amniotic fluid cells, there was agreement of results in 65. In the one case of disagreement the result of GAG analysis proved to be correct. Fourteen pregnancies were predicted to be affected and the predictions were confirmed by studies on fetal tissues and/or cultured cells, or in one case the birth of an affected infant. Of the 58 pregnancies predicted to be unaffected, 48 have so far gone to term and produced healthy infants. There have been no false negative predictions. The analytical method is simple, rapid, and, in this study, has been found completely reliable for prenatal diagnosis. 相似文献
307.
308.
钻屑、钻井液固化处理及对环境的影响分析 总被引:10,自引:3,他引:10
钻屑和废钻井液的固化处理是现阶段钻井废物无害化处理的主要研究方向,研究利用固化剂对钻屑和废泥浆进行固化处理,优选配方(水泥+粉煤灰+添加剂)进行固化处理;同时考查了钻屑、钻井液固化填埋后对周围环境的影响。结果表明,固化物浸出液的分析结果符合国家危险废物鉴别标准(GB5085.3-1996)和国家污水综合排放标准(GB8978-1996),对周围环境水质调查监测,环境水质未受到污染,与填埋前的监测指标变化不大。 相似文献
309.
磁流体在印染废水处理中的应用研究 总被引:1,自引:0,他引:1
随着工业的迅速发展,大量工业废水的排放给人类生存造成了严重的威胁,尤其是印染废水,因此寻求有效的处理方法是亟待解决的问题。一种新的印染废水处理技术——应用磁流体来处理印染废水,分别研究了Fe3O4磁流体在不同条件(如pH值、表面活性剂的投加量、搅拌时间、温度等)下,对降低印染废水的COD和色度两个方面的影响。实验表明当pH=11,表面活性剂量是亚铁量的0.16倍,磁流体与废水的比大于1:10时COD降低最多,脱色效果最好。 相似文献
310.