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771.
Climate change exposes economic systems to numerous risks, including reduced agricultural production and electric power supply shortages. The interdependent nature of economic systems causes disruptions in any sector to cascade to other sectors via forward and backward linkages. This work develops an optimization model with which allocation of scarce goods or resources can be optimized; the model uses an overall index of satisfaction of fuzzy economic output goals under conditions of scarcity caused by climatic disruptions. The proposed model includes a vulnerability measure that integrates information elicited from expert judgment. A case study based on a scenario of drought-induced electricity shortage in the Philippine economy is examined. Results show that trade, transportation and service-oriented industries suffer losses in gross domestic product in the Philippine case.  相似文献   
772.
A comparative analysis of municipal solid waste management (MSWM) in Singapore and Berlin was carried out in order to identify its current status, and highlight the prevailing conditions of MSWM. An overview of the various aspects of MSWM in these two cities is provided, with emphasis on comparing the legal, technical, and managerial aspects of MSW. Collection systems and recycling practiced with respect to the involvement of the government and the private sector, are also presented.Over last two decades, the city of Berlin has made impressive progress with respect to its waste management. The amounts of waste have declined significantly, and at the same time the proportion that could be recovered and recycled has increased. In contrast, although Singapore’s recycling rate has been increasing over the past few years, rapid economic and population growth as well as change in consumption patterns in this city-state has caused waste generation to continue to increase. Landfilling of MSW plays minor role in both cities, one due to geography (Singapore) and the other due to legislative prohibition (Berlin). Consequently, both in Singapore and Berlin, waste is increasingly being used as a valuable resource and great efforts have been made for the development of incineration technology and energy recovery, as well as climate protection.  相似文献   
773.
A life cycle assessment was conducted to evaluate the environmental and economic effects of sewage sludge co-incineration in a coal-fired power plant. The general approach employed by a coal-fired power plant was also assessed as control. Sewage sludge co-incineration technology causes greater environmental burden than does coal-based energy production technology because of the additional electricity consumption and wastewater treatment required for the pretreatment of sewage sludge, direct emissions from sludge incineration, and incinerated ash disposal processes. However, sewage sludge co-incineration presents higher economic benefits because of electricity subsidies and the income generating potential of sludge. Environmental assessment results indicate that sewage sludge co-incineration is unsuitable for mitigating the increasing pressure brought on by sewage sludge pollution. Reducing the overall environmental effect of sludge co-incineration power stations necessitates increasing net coal consumption efficiency, incinerated ash reuse rate, dedust system efficiency, and sludge water content rate.  相似文献   
774.
选用聚合氯化铝(PAC)与高锰酸钾、羟基氧化铁进行复配,强化混凝处理微污染原水。研究了复合混凝剂投加量、反应时间、进水pH、进水有机物浓度等对混凝效果的影响及絮体的沉淀性能。结果表明,PAC-KMnO4-β-FeOOH三元复合混凝剂具有显著的强化混凝效果,与相同条件下单投PAC及PAC-KMnO4二元复合混凝相比,TOC去除率分别提高了30%与20%。达到相同的浊度去除效果,三元复配混凝剂可缩短27%~50%的反应时间,减少65%~75%的沉淀时间。进水pH、有机物浓度在一定范围内变动时,PAC-KMnO4-β-FeOOH三元复合混凝剂对浊度与TOC的去除率均高于单投PAC的处理效果,三元复合混凝剂具有较强的抗水质变化冲击能力。  相似文献   
775.
Titania nanotubes are gaining prominence in photocatalysis, owing to their excellent physical and chemical properties such as high surface area, excellent photocatalytic activity, and widespread availability. They are easily produced by a simple and effective hydrothermal method under mild temperature and pressure conditions. This paper reviews and analyzes the mechanism of titania nanotube formation by hydrothermal treatment. It further examines the parameters that affect the formation of titania nanotubes, such as starting material, sonication pretreatment, hydrothermal temperature, washing process, and calcination process. Finally, the effects of the presence of dopants on the formation of titania nanotubes are analyzed.  相似文献   
776.
In densely populated urban areas, in the event of the toxic gases leak, how to accurately determine the risky zone and take effective measures to evacuate inhabitants quickly out of dangerous areas and minimize the unexpected losses is a tropical topic in China. First, the ALOHA code defined any interested accidents scenarios. For any different exposure times and concentrations, the distances down wind direction could be determined, which eventually generated the dead zone, wounded zone, injured zone and evacuation zone. Then, it presented the procedure of an emergency evacuation routes selection, the choice of the principle of refuges and shelters for evacuated inhabitants, as well as evacuation traffic organizations, vehicle assignments, real-time communications and other traffic evacuation strategies. Finally, the OREMS code was proposed to study the sudden leak accident and design emergency response policies (ERP). A sudden gaseous leakage incident in Tianjin Olympic stadium was chosen as an example to verify the raw ERP including the evacuation road network design, the evacuation time for vehicles, vehicle running conditions and the possible road congestions. Results showed that when the radium of the emergency evacuation scope is about 3 km, the time for evacuation of 50% vehicles is proper.  相似文献   
777.
随着重金属污染的越来越重,重金属对土壤环境的危害引起人们广泛的关注,土壤酶作为土壤生态系统中生化反应的催化剂,对各种土壤代谢过程起驱动作用.为研究单因素重金属Cu、Cd对于土壤脲酶活性的影响,以至于对环境保护和环境评价工作提供意见.本文采用靛酚蓝比色法测定脲酶活性,以氨氮浓度表征土壤脲酶活性.实验结果表明,随着Cu2+、Cd2+浓度的增加,土壤脲酶活性显著降低,即重金属对土壤脲酶具有抑制作用.  相似文献   
778.
环境库兹涅茨曲线(Environmental Kuznets Curve,简称EKC),常用来描述经济增长与环境质量之间的关系,传统的环境库兹涅茨曲线一般具有倒"U"形特征。通过对1990年-2010年台州市环境数据和经济数据的计量模型研究,发现台州市排放的污染物环境库兹涅茨曲线不完全符合传统的环境库兹涅茨曲线特征,并对这一结果进行了深入分析。环境质量的改善并不是随着人均GDP的增长而自动发生。除了经济收入这个因素外,影响环境质量的因素还有很多,如种族构成、公民受教育程度、集体行动的倾向性、人口密度等等。经过研究得出结论:台州市总体环境状况有着进一步恶化的趋势,应该加大环保力度,提倡清洁生产和"三废"循环利用,使经济增长与环境状况同时向着有利于人类的方向发展,实现可持续发展。  相似文献   
779.
环境影响评价既是技术,也是正确处理环境保护与经济增长关系的重要手段,是强化环境管理的积极措施,可为经济发展和环境保护决策提供参考依据。本文梳理总结了近年来红桥区污染物排放情况、环境影响评价预测污染物排放情况以及环境影响评价消减污染物排放情况,分析了红桥区环境影响评价的执行情况,通过对红桥区实践环境影响评价出现的问题分析,针对性地提出建议。  相似文献   
780.
大气颗粒物对水芹和白菜可食部位铅镉砷累积的影响   总被引:4,自引:0,他引:4  
近年来京津冀地区雾霾天气频发,大气颗粒物聚集为其主要原因之一.细颗粒物负载的重金属一定程度上会影响叶菜类蔬菜可食部位重金属的积累.本研究以水生和旱生叶菜类蔬菜水芹、白菜为主要对象,采用营养液培养和土壤培养试验,探索了不同生长环境下(生活区和工业区,以室内培养箱作为对照)蔬菜可食部位铅(Pb)、镉(Cd)、砷(As)的累积特征及大气颗粒物的贡献程度.结果表明,水芹、白菜可食部位Pb、Cd、As含量呈现工业区生活区对照的趋势(p0.05),其中工业区生长的水芹、白菜中Pb含量分别为对照的49.1倍和20.0倍,均超出我国食品安全标准中叶菜蔬菜铅的安全限值(GB 2762-2012).经分析工业区大气颗粒物对水芹、白菜Pb累积贡献率分别高达98%和93%,工业区大气PM_(2.5)中Pb质量浓度显著高出生活区24.3倍(p0.01),且土培白菜与大气PM_(2.5)中Pb含量呈极显著的正相关关系,这些均表明大气颗粒物对叶菜类蔬菜中铅富集的直接影响.此外,尽管大气颗粒物对水芹和白菜中Cd、As的累积贡献高达78.3%~99.3%,但工业区大气PM_(2.5)中Cd、As的质量浓度相对较低,因此,所有水芹、白菜样品中Cd、As含量均符合我国食品安全标准.综上所述,大气颗粒物直接影响着露地叶菜类蔬菜可食部位重金属的富集.  相似文献   
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