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561.
The key stocks and flows of phosphorus (P) through food consumption in Beijing and Tianjin, two megacities in northern China, were explored using a material flow analysis (MFA) approach to construct a static model of P metabolism. A total of 4498 t P has accumulated with 72% of P flow imported through food consumption eventually remaining in Beijing in 2008. Around 64% of the total inflow of P (2670 t) remained in Tianjin in 2008. P in the uncollected sewage from both urban and rural residents and the effluents from sewage treatment plants has significant negative effects on water quality. An average of 55% the P flow remained in the sewage sludge through urban food consumption. The key problems in P metabolism and management in megacities are identified based on the quantitative analysis of P cycling through food consumption. Relevant solutions for improving P recycling efficiency are also discussed. It is important to link P flows with environmental regulations and to establish a strong coordination between urban and rural areas for nutrient recycling to attain sustainable development of megacities. 相似文献
562.
株洲高新区以长株潭(长沙市、株洲市、湘潭市)两型社会示范建设为契机,规划建设以低碳经济为主体产业的国家生态工业示范园区。株洲高新区在有色金属深加工、先进制造等行业的科研创新体系日趋完善,且产业集群初具规模,已具备了创建国家生态工业示范园区的有利条件。通过国家生态工业示范园区创建工作,将进一步优化区域产业结构,推动产业联动发展。园区建设总体上分为产业循环体系、污染控制体系和保障体系三部分。 相似文献
563.
生态文明理念与循环经济新发展方式,都是人类在反思生态危机的过程中提出的,具有共同的历史背景和时代意义.阐述了生态文明是发展循环经济的指导思想和价值追求,剖析了发展循环经济是落实科学发展观、实现生态文明的基本途径.从本质上看,生态文明与循环经济是一致的,都追求环境保护、经济发展与社会进步的协调统一和可持续发展. 相似文献
564.
Kinetics of oxidative decolorization and mineralization of Acid Orange 7 by dark and photoassisted Co2+-catalyzed peroxymonosulfate system 总被引:1,自引:0,他引:1
A kinetic model was proposed and used to interpret the experimental data for degradation of Acid Orange 7 (AO7) in aqueous solution induced by Co(2+)/peroxymonosulfate (Co/PMS) reagent in terms of both decolorization and mineralization. The pseudo first-order decolorization rate constants are related to [Co(2+)], [PMS], reciprocal of [H(+)] and [AO7](0). Activation energy of the AO7 decolorization process was determined to be 75.7 kJ mol(-1). UV and visible light can accelerate the decolorization and mineralization process due to different mechanisms. In the combined UV/Co/PMS system, UV light can decompose PMS to generate hydroxyl ((*)OH) and sulfate radicals (SO(4)(*-)), while in the Vis/Co/PMS system, excited AO7 molecules can transfer electrons to PMS or Co(3+) and thus accelerate the decomposition of PMS and catalytic cycle of Co(3+)/Co(2+). 相似文献
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567.
环境一号卫星环境应用系统工程及其关键技术研究进展 总被引:3,自引:1,他引:2
简介长达11年的国家重点项目“环境一号卫星环境应用系统工程及其关键技术研究”的核心内容及其重要研究成果,对环境一号卫星系统需求分析、设计理论、研制发射和运行应用全过程进行了完整的研究与实践,为环境一号卫星系统的建设、应用和业务运行奠定了重要基础。 相似文献
568.
Fangkun Zhu Xuejing Wang Wenxiu Fan Li Qu Meiying Qiao Shuwen Yao 《Environmental monitoring and assessment》2013,185(5):3909-3916
Herbal tea is consumed widely in China due to their therapeutic efficacy, mild features, and relatively low cost. To assess the health risk associated with drinking herbal tea, arsenic and seven heavy metals, namely Cu, Zn, Fe, Mn, Cd, Ni, and Pb in eight different types of herbal flowers and their infusions were determined by inductively coupled–mass spectrometry after microwave digestion. The accuracy and precision of the analytical method were confirmed by the certified reference material (GBW 07605). The results suggested that significant differences existed in all metal concentrations determined among different varieties of herbal flowers and their infusions. In general, the concentration of iron was higher than those of seven other metals in the investigated herbal flowers and their infusions. The hazard quotient (HQ) and hazard index (HI) were calculated to evaluate the noncarcinogenic health risk from individual metal and combined metals due to the dietary intakes via consumption of herbal infusions. Both the HQ and HI levels were far below one, suggesting that the dietary intakes of the eight metals determined from daily consumption 4.5 g of the investigated herbal flowers for a normal adult should pose no potential risk to human health. 相似文献
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