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31.
Thin-film technique is becoming an industry standard for the preparation of TiO2-based photocatalyst for organic destruction. The catalyst provides several advantages over the conventional powder TiO2 in the treatment of wastewater and groundwater. In this study, a continuous stir flow reactor model is developed capable of describing the photocatalytic process. The model incorporates the following fundamental mechanisms: adsorption, diffusion, liquid-film transfer, UV attenuation, and photocatalytic reaction. All of the simulation results indicate that there exists a highly nonlinear relation between each of these parameters and the destruction rate. Various incident light intensities also are incorporated to simulate the energy efficiency. The simulations illustrate that the photocatalytic model can be used to elucidate the effect of process variables. It is also possible to “custom-design” a catalyst for the treatment of a particular waste stream. 相似文献
32.
博斯腾湖水质矿化度模型及预测研究 总被引:6,自引:0,他引:6
根据博斯腾湖1985~1995年水质监测数据和出入湖水量等水文数据观测值,采用水质扩散模型和盐量平衡关系推导出博斯腾湖大湖区(简称博湖)水质矿化度模型,并预测了几种情况下博湖水质矿化度及近几年变化趋势,分析了影响博湖水质矿化度的主要因素,为博湖的近期和远期环境保护规划、环境管理等提供科学依据. 相似文献
33.
研究了乌鲁木剂铁路局系统污水治理污染控制方法及途径,提出了主要污染物为石油类,其最佳治理对策是:确定重点污染单位、污染源、用最低的治理投入,选择斜板隔油气浮工艺治理重点污染和次重点污染部门,得到较好的治理效果,否定盲目追求“零排放”的高投入方案。 相似文献
34.
我国海洋环境污染监测质量保证的回顾与展望 总被引:1,自引:0,他引:1
我国海洋环境污染监测质量保证的发展历史可大致分为三个阶段:孕育阶段(1972~1977年)起步阶段(1978~1983年)和发展阶段(1984~)。各个阶段有不同的特色和侧重点,1978年前主要探索与污染物质的分析方法,1984年后是监测质量保证工作进入管理时期。 相似文献
35.
介绍了多级活性生化处理 (MSABP)这项新的废水处理技术的原理、技术特点及两个实例运用。这是此项技术在国内的首次运用 ,其最大的优点是无剩余污泥产生 ,不需要沉淀池 相似文献
36.
Specific PCR amplification and probe hybridization techniques were applied to examine the compositions of airborne fungi in samples from three different environments. The results from microscopic and CFU counting were compared to those of the molecular-based detections. The detection sensitivity for PCR amplifications was 9 to 73 spores and 1.3 to 19.3 CFUs per PCR reaction. The hybridization detection limit was 2 to 4 spores and 0.2 to 1.2 CFU. The hybridization method was more sensitive than PCR amplification and showed less variation among samples. Using specific PCR primers and probes we identified the presence of several fungal groups and species in the air samples. Specific detections through probe hybridization to PCR products amplified with universal or group-specific fungal primers have promising applications in the examination of air samples for environmental monitoring. 相似文献
37.
In this work a comparison is made between the different approaches that can be taken to evaluate the mobility of elements in compost. The practical consequences of the results obtained are also discussed in terms of methods for cleaning up compost and using compost in environmental remediation. The mobility of potentially toxic elements in compost is evaluated by leaching with four selected eluents, i.e. diluted sulfuric acid, oxalate, citrate and EDTA. In contrast to the chelating agents, diluted sulfuric acid was found to generally have a low leaching capability for removal of heavy metals from compost. This implies that the risk of heavy metal leaching caused by natural rainfall is likely to be low. The results obtained in the leaching experiment were compared with previous results obtained from sequential fractionation. This comparison confirmed that both methods gave similar results for predicting the lability of elements in compost. A non-linear regression analysis of the leaching curves was also conducted. The leaching curves for elements with high lability could be fitted with a two components model. The labile components identified by the kinetic model are approximately in accordance with the fractions obtained from the first step of the sequential extraction method. The kinetic speciation method is shown to be a relatively rapid and simple procedure for compost which gives more information about element lability than simple leaching experiments. The leaching reagents used in this work were not effective enough to be used for cleaning up compost with a high metal content. Compost was however shown to have a high affinity for heavy metals, with the order of affinity of metal for the compost being very similar to that seen for humic acid. Compost may therefore prove to be a good remediation material for metal contaminated waste. 相似文献
38.
汽车尾气污染及其净化处理技术 总被引:1,自引:0,他引:1
本文详细阐述了汽车尾气的有害成份及其对人类健康的危害。为此 ,应该采取净化处理措施 ,减少或者消除有害气体的产生 ,为大气环境洁净而创造条件。 相似文献
39.
福建省森林固定CO2价值评估 总被引:10,自引:0,他引:10
借鉴国内外研究成果,引入“市场逼近系数”,构造森林固定CO2效益经济结构模型,评估福建省森林固定CO2价值,为福建省森林资源的科学管理和资产评估提供了借鉴和参考。 相似文献
40.
对多环芳烃(PAHS)4种理化参数(K;W、Sw。X Vv。)与 LCO的相关关系进行了研究,建立了 4种一元线性回归方程。结果表明,4种参数的相关系数分别为:0.刀66、08083、09488、0.9570,经r检验,后两种属高度显著相关.用所建立的一元线性回归方程对7种PAHS的LC。进行估算,估算值与实测值相比,平均相对误差分别为58.84%、32.23%、1761%、198%,用l和V*.H对LClj进行估算的估算精度也较高。经比较,提出用(。估算P*比对麦穗鱼*CO的新方法。 相似文献