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981.
研究了非甾体抗炎药双氯芬酸的吸附去除过程与机制。对吸附处理效果较好的活性炭与纳米羟基氧化铁(α-FeOOH)进行了比表面积、Zeta电位等表面特性的表征,研究比较了双氯芬酸在活性炭与α—FeOOH2种材料上的吸附去除效果与吸附机制。结果表明,在相同的实验条件下,活性炭与α-FeOOH对双氯芬酸吸附去除率可分别达到97.9%和84.3%;双氯芬酸在活性炭上的吸附主要是由于活性炭较大的比表面积与疏水分配作用,在α-FeOOH上的吸附主要是由于静电引力作用;活性炭与α-FeOOH对双氯芬酸的吸附去除效果均随pH的升高而降低;在pH=6时,活性炭与α-FeOOH对双氯芬酸钠的吸附等温线均符合Langmuir方程,单位饱和吸附量分别为109.98mg/g和58.96mg/g;活性炭对双氯芬酸具有更强的吸附能力。  相似文献   
982.
The effect of the general growth of CO vehicular emissions in urban areas on the CAMP station measurements in downtown areas, where vehicular traffic is saturated is considered. With the assumption that the street-level CO concentration is derived from the sum of an urban background term and a local street-effect term, the urban background CO concentration is computed with a diffusion model by introducing a simple area source distribution. The local street-effect term is taken to be constant at a saturation emission level corresponding to a saturation traffic density when the emission per vehicle-mile and meteorological conditions are fixed. The present analysis indicates that the local street-effect term, AC, has a major role in determining street-level concentrations for pollutants, such as CO, whose air quality standard is based on maximum concentrations with averaging times of 1 hour and 8 hours. The relevance of this analysis to the abatement requirements of the Clean Air Amendments and to the driving cycle adopted is discussed.  相似文献   
983.
984.
985.
Fate and transport of engineered nanomaterials in the environment   总被引:1,自引:0,他引:1  
With the fast development of nanotechnology, engineered nanomaterials (ENMs) will inevitably be introduced into the various environment. Increasing studies showed the toxiccity of various ENMs, which raises concerns over their fate and transport in the environment. This review focuses on advances in the research on environmental transport and fate of ENMs. Aggregation and suspension behaviors of ENMs determining their fate and transport in aqueous environment are discussed, with emphasis on the influencing factors, including natural colloids, natural organic matter, pH, and ionic strength. Studies on the transport of ENMs in porous media and its influencing factors are reviewed, and transformation and organismcleansing, as two fate routes of ENMs in the environment, are addressed. Future research directions and outlook in the environmental transport and fate of ENMs are also presented.  相似文献   
986.
Municipal solid waste management (MSWM) is an important environmental challenge and subject in urban planning. For sustainable MSWM strategies, the critical management factors to be considered include not only economic efficiency of MSW treatment but also life-cycle assessment of the environmental impact. This paper employed linear programming technique to establish optimal MSWM strategies considering economic efficiency and the air pollutant emissions during the life cycle of a MSWM system, and investigated the correlations between the economical optimization and pollutant emissions. A case study based on real-world MSW operating parameters in Taichung City is also presented. The results showed that the costs, benefits, streams of MSW, and throughputs of incinerators and landfills will be affected if pollution emission reductions are implemented in the MSWM strategies. In addition, the quantity of particulate matter is the best pollutant indicator for the MSWM system performance of emission reduction. In particular, this model will assist the decision maker in drawing up a friendly MSWM strategy for Taichung City in Taiwan.

Implications: Recently, life-cycle assessments of municipal solid waste management (MSWM) strategies have been given more considerations. However, what seems to be lacking is the consideration of economic factors and environmental impacts simultaneously. This work analyzed real-world data to establish optimal MSWM strategies considering economic efficiency and the air pollutant emissions during the life cycle of the MSWM system. The results indicated that the consideration of environmental impacts will affect the costs, benefits, streams of MSW, and throughputs of incinerators and landfills. This work is relevant to public discussion and may establish useful guidelines for the MSWM policies.  相似文献   
987.
膜生物反应器内流场动力学特性的PIV实验研究   总被引:2,自引:0,他引:2  
浸没式膜生物反应器系统内膜面附近的气液两相流动力学特性对控制浓差极化和膜污染具有重要影响。应用粒子图像测速(PIV)技术对浸没式膜生物反应器内近膜面的液相流场动力学特性进行了研究。采用相分离技术灰度分辨法将通过PIV技术得到的气液两相流场图像中的液相速度场进行辨别,得到膜面附近的液相流场数据,并应用Tecplot软件计算得出液相流的涡量特性。在3 mm曝气孔径,2.5、3.0、3.5、4.5、5.5和6.5 m3/h 6种曝气强度下分析了膜面附近的液相速度场和涡量场。结果表明,曝气强度对液相流场和涡量场的影响较大,在一定范围内增加曝气强度可以使得液相速度和涡量增加,同时,分析了3 mm孔径下圆帽状气泡的动力学特性。研究结果为膜生物反应器系统的优化设计提供了研究经验和实验数据。  相似文献   
988.
含二甲胺工业废水的回收及再利用技术研究   总被引:1,自引:0,他引:1  
为了消除工业二甲胺废水带来的巨大污染,使其达到回收利用的目的,利用精馏技术,采用BH型高效填料作为分离介质,连续从废水中脱除二甲胺,并将塔顶二甲胺提浓。结果表明,采用本技术可使塔顶二甲胺提浓至47%(质量百分含量),达到满足40%二甲胺水溶液质量要求的目的;塔釜二甲胺含量降低至≤50 mg/L,此水可作皮革工业生产回用水。由于含二甲胺废水经处理后可以全部回收利用,表明该高效精馏技术用于清洁生产中具有可靠性和实用性。  相似文献   
989.
Abstract

This study introduces the principles of KMG's (Kaoshiung Municipal Government) dealing with the non-poisonous urban and industrial waste through reclamation of shore land in reinforcing a sense of coastal protection and land development in Tai-Lin-Pu coastal area, southern Taiwan.

Through a series of experimental studies, we found that substitutes of coarse aggregate with a broad spectrum of integrating slag powder, fly ash, and cementitious material can be obtained with a benefit up to 80% saving of cement. the integrated aggregates from the non-poisonous industrial wastes were subsequently made into armour units and used in the field tests at Tai-Lin-Pu coastal area, where the shorelines are seriously eroded. After being subjected to several severe typhoon advents, the results showed that the waste-made units used as the protection breakwater, together with construction wastes and excavated soil as the filling material, prove to be an effective practice in utilizing recycled urban waste to reclaim erosive shore lands. Moreover, this study also demonstrates that through detailed analysis of the waste characteristics, scrap material could be turned into valuable construction aggregates, and highlights the value of non-poisonous urban and industrial waste as a alternative resource for the shore protection engineering.  相似文献   
990.
粉煤灰基混凝剂制备及处理印钞废水研究   总被引:4,自引:1,他引:3  
将粉煤灰经过超细球磨后再采用微波处理,用于制备粉煤灰基混凝剂。结果表明,超细和微波处理能明显增加混凝剂的产率和性能。通过正交实验确定了去除印钞废水中浊度的粉煤灰基混凝剂的最佳制备工艺条件:粉煤灰/酸比为1∶4(w/v),粉煤灰/碱比为1∶3(w/v),熟化温度为40℃。当投加量为5 mL/100 mL时,粉煤灰基混凝剂对印钞废水处理的浊度去除率为98.37%。对粉煤灰基混凝剂的混凝机理进行了分析。  相似文献   
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