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981.
旋流板塔内石灰湿法烟气脱硫的试验研究   总被引:14,自引:3,他引:14       下载免费PDF全文
试验研究了在旋流板塔内以石灰湿法进行烟气脱硫率的影响,并对试验结果进行了分析讨论,得出了回归关联式。本研究为工业装置的设计、操作和运行提供了所必需的基础数据。  相似文献   
982.
珠江三角洲表层土壤中的多环芳烃   总被引:4,自引:0,他引:4  
余莉莉  李军  刘国卿  刘向  祁士华  张干 《生态环境》2007,16(6):1683-1687
多环芳烃是一类主要由人类活动排放的有毒有机污染化合物,对人和生物体具有致癌、致畸和致突变效应,是评价土壤生态污染的重要内容之一。文章利用螺旋钻采样、索氏抽提、硅胶氧化铝净化和GC-MS分析,研究了珠江三角洲不同功能区(城市点、郊区点、乡村点)的76个表层土壤样品(耕作土、非耕作土)中多环芳烃(PAHs)的含量、分布特征及其影响因素。结果表明,16种优控PAHs的总质量分数范围为31.5~791.6ng·g-1(平均279.1ng·g-1,以干质量计),以萘(44.4%)、菲(13.7%)、荧蒽(8.4%)、芘(4.9%)、■(6.6%)等化合物为主。与国内外其它地区的城市相比较,珠江三角洲地区土壤PAHs的污染程度较低,在组成上也表现出亚热带地区独特的中、低环化合物为主的特征。受人类经济活动的影响,地处珠江三角洲中部的经济工业中心地带,土壤中PAHs含量相对较高。珠三角表层土壤PAHs含量和组成分布主要受大气沉降控制,而与土壤有机碳、pH的相关性较小。高温潮湿的亚热带季风气候是影响珠三角土壤PAHs的降解和迁移的重要环境因素。  相似文献   
983.
针对目前应急响应方案存在无法适应区域特征的问题,从柔性的角度出发,提出具有区域针对性的应急响应方案生成方法。通过分析区域应急需求,总结方案中的柔性要素;采用层次网络的方式对应急响应方案进行建模,提出要素和要素之间关系的确定方法,并分共性和个性2部分表示应急响应方案柔性生成框架;模拟地震灾害情景,实现柔性应急响应方案生成方法的案例验证,结果表明:该方法可以反映区域特点,高效有序并有针对性地完成有关突发事件的应对工作。  相似文献   
984.
韩忠明  潘勇延 《化工环保》2016,36(2):193-199
采用“混凝沉淀-微滤-组合反渗透”工艺对某煤化工企业的高盐废水进行浓缩处理,浓水通过蒸发结晶进行脱水,产水采用常规反渗透进行水回收。运行结果表明,经30 d运行,水回收率保持在85%以上,脱盐率稳定在95%以上,常规反渗透产水水质稳定,产水电导率、浊度、Cl-质量浓度和COD的平均值分别为12.5 μs/cm,0.1 NTU,7.8 mg/L,1.8 mg/L,满足《炼化企业节水减排考核指标与回用水质控制指标》(Q/SH0104-2007)中污水回用于循环冷却水的水质指标和设计产水水质要求,实现了废水的近“零排放”。  相似文献   
985.
To develop a depth filter based on the electrostatic adsorption principle, positively charged microporous ceramic membrane was prepared from a diatomaceous earth ceramic membrane.The internal surface of the highly porous ceramic membrane was coated with uniformly distributed electropositive nano-Y_2O_3 coating. The dye removal performance was evaluated through pressurized filtration tests using Titan Yellow aqueous solution. It showed that positively charged microporous ceramic membrane exhibited a flow rate of 421 L/(m~2·hr) under the trans-membrane pressure of 0.03 bar. Moreover it could effectively remove Titan Yellow with feed concentration of 10 mg/L between pH 3 to 8. The removal rate increased with the enhancement of the surface charge properties with a maximum rejection of 99.6%. This study provides a new and feasible method of removing organic dyes in wastewater. It is convinced that there will be a broad market for the application of charged ceramic membrane in the field of dye removal or recovery from industry wastewater.  相似文献   
986.
以兰州某石化公司化工污水处理厂恶臭治理项目为例,在确定恶臭气体的污染源源强的基础上,采用AERMOD模式预测污染物扩散情况。结果表明,添置除臭装置后,NH3的臭气浓度减少了90%,VOCs的臭气浓度减少了88%。同时,当恶臭污染物浓度达到环境质量浓度标准时,NH3的臭气强度为1.40级,VOCs的臭气强度为0.82级,人们仍能感觉到气味。因此石化企业在进行恶臭治理过程中需综合考虑污染物的环境空气质量浓度标准和臭气强度,以期改善环境空气质量。  相似文献   
987.
To evaluate the toxicity of two fluoroquinolones (FQs), ciprofloxacin (CPFX), and enrofloxacin (ENFX), at the protein level, their binding modes with bovine serum albumin (BSA) were characterized by multiple spectroscopic and molecular docking methods under simulated physiological conditions. On the basis of fluorescence spectra, we concluded that both FQs greatly quenched the fluorescence intensity of BSA, which was attributed to the formation of a moderately strong complex mainly through electrostatic interactions. Besides, CPFX posed more of an affinity threat than ENFX. The molecular docking methods further illustrated that both CPFX and ENFX could bind into the subdomain IIIA of BSA and interact with Arg 508 and Lys 437, the positively charged residues in protein. Furthermore, as shown by the synchronous fluorescence, UV-Visible absorption and circular dichroism data, both CPFX and ENFX could lead to the conformational and microenvironmental changes of BSA, which may affect its physiological function.  相似文献   
988.
Alternating flooding and drainage conditions have a strong influence on redox chemistry and the solubility of trace metals in paddy soils. However, current knowledge of how the effects of water management on trace metal solubility are linked to trace metal uptake by rice plants over time is still limited. Here, a field-contaminated paddy soil was subjected to two flooding and drainage cycles in a pot experiment with two rice plant cultivars, exhibiting either high or low Cd accumulation characteristics. Flooding led to a strong vertical gradient in the redox potential (Eh). The pH and Mn, Fe, and dissolved organic carbon concentrations increased with decreasing Eh and vice versa. During flooding, trace metal solubility decreased markedly, probably due to sulfide mineral precipitation. Despite its low solubility, the Cd content in rice grains exceeded the food quality standards for both cultivars. Trace metal contents in different rice plant tissues (roots, stem, and leaves) increased at a constant rate during the first flooding and drainage cycle but decreased after reaching a maximum during the second cycle. As such, the high temporal variability in trace metal solubility was not reflected in trace metal uptake by rice plants over time. This might be due to the presence of aerobic conditions and a consequent higher trace metal solubility near the root surface, even during flooding. Trace metal solubility in the rhizosphere should be considered when linking water management to trace metal uptake by rice over time.  相似文献   
989.
A field investigation, field experiment, and hydroponic experiment were conducted to evaluate feasibility of using Oenothera glazioviana for phytostabilization of copper-contaminated soil. In semiarid mine tailings in Tongling, Anhui, China, O. glazioviana, a copper excluder, was a dominant species in the community, with a low bioaccumulation factor, the lowest copper translocation factor, and the lowest copper content in seed (8 mg kg?1). When O. glazioviana was planted in copper-polluted farmland soil in Nanjing, Jiangsu, China, its growth and development improved and the level of γ-linolenic acid in seeds reached 17.1 %, compared with 8.73 % in mine tailings. A hydroponic study showed that O. glazioviana had high tolerance to copper, low upward transportation capacity of copper, and a high γ-linolenic acid content. Therefore, it has great potential for the phytostabilization of copper-contaminated soils and a high commercial value without risk to human health.  相似文献   
990.
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