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401.
The rapid growth of China’s economy has led to severe air pollution characterized by acid rain, severe pollution in cities, and regional air pollution. High concentrations are found for various pollutants such as sulfur dioxides (SO2), nitrogen oxides (NOx), and fine particulates. Great efforts have thus been undertaken for the control of air pollution in the country. This paper discusses the development and application of appropriate technologies for reducing the major pollutants produced by coal and vehicles, and investigates air quality modeling as an important support for policy-making.  相似文献   
402.
Recent increases in ivory poaching have depressed African elephant populations. Successful enforcement has led to ivory stockpiling. Stockpile destruction is becoming increasingly popular, and most destruction has occurred in the last 5 years. Ivory destruction is intended to send a strong message against ivory consumption, both in promoting a taboo on ivory use and catalyzing policy change. However, there has been no effort to establish the distribution and extent of media reporting on ivory destruction events globally. We analyzed media coverage of the largest ivory destruction event in history (Kenya, 30 April 2016) across 11 nation states connected to ivory trade. We used an online‐media crawling tool to search online media outlets and subjected 5 of the largest print newspapers (by circulation) in 5 nations of interest to content analysis. Most online news on the ivory burn came from the United States (81% of 1944 articles), whereas most of the print news articles came from Kenya (61% of 157 articles). Eighty‐six to 97% of all online articles reported the burn as a positive conservation action, whereas 4–50% discussed ivory burning as having a negative impact on elephant conservation. Most articles discussed law enforcement and trade bans as effective for elephant conservation. There was more relative search interest globally in the 2016 Kenyan ivory burn than any other burn in 5 years. Ours is the first attempt to track the reach of media coverage relative to an ivory burn and provides a case study in tracking the effects of a conservation‐marketing event.  相似文献   
403.
Environmental Science and Pollution Research - Beijing and its surrounding areas implemented a series of stringent measures to ensure good air quality during the Asia-Pacific Economic Cooperation...  相似文献   
404.
Environmental Science and Pollution Research - As China and other developing countries continue to urbanize over the next decades, construction and demolition waste (CDW) management has been...  相似文献   
405.
百年工业文明发展范式对自然环境的持续作用,使人类面临环境与发展的双重危机。生态文明具有内在统一性,环境法制是生态文明的应有之义。环境基本法是环境法制的基石,目的条款是环境基本法的元点。旧的目的条款沿袭工业文明发展范式,将发展经济奉为圭臬,始终无法调和人与自然的内在矛盾。修改环境基本法目的条款,融入生态文明因子具有自内而外、自外而内、自上而下以及自下而上四个方面的动力因素。  相似文献   
406.
407.
Difusive carbon dioxide(CO2) emissions from the water surface of the Three Gorges Reservoir, currently the largest hydroelectric reservoir in the world, were measured using floating static chambers over the course of a yearlong survey. The results showed that the average annual CO2 flux was(163.3 ± 117.4) mg CO2/(m2·hr) at the reservoir surface, which was larger than the CO2 flux in most boreal and temperate reservoirs but lower than that in tropical reservoirs. Significant spatial variations in CO2 flux were observed at four measured sites, with the largest flux measured at Wushan(221.9 mg CO2/(m2·hr)) and the smallest flux measured at Zigui(88.6 mg CO2/(m2·hr)); these diferences were probably related to the average water velocities at diferent sites. Seasonal variations in CO2 flux were also observed at four sites, starting to increase in January, continuously rising until peaking in the summer(June-August) and gradually decreasing thereafter. Seasonal variations in CO2 flux could reflect seasonal dynamics in pH, water velocity,and temperature. Since the spatial and temporal variations in CO2 flux were significant and dependent on multiple physical, chemical,and hydrological factors, it is suggested that long-term measurements should be made on a large spatial scale to assess the climatic influence of hydropower in China, as well as the rest of the world.  相似文献   
408.
针对北京建工环境发展有限责任公司旗下的24家污水处理厂,重点研究确定污水处理厂运营管理信息系统的基本要求与组织架构,开发完成污水处理厂运营管理信息系统软件,并通过系统软件在北京建工环境旗下污水处理厂的推广应用,达到提高运营管理水平、节本增效的目的.  相似文献   
409.
水情自动测报系统在唐徕渠水量调度中的应用问题,是由于水资源的日益紧缺,为推进节水型灌域建设,解决灌区的用水矛盾,文中介绍了唐徕渠灌区的基本概况,探讨了水情自动测报系统建设,从对唐徕渠水量调度情况的分析,提出建立水情自动测报系统后对水量调度工作的影响,探讨了水情自动测报系统与科学调度水量、水情自动测报系统与干渠险情、水情自动测报系统与管理效率、水情自动测报系统与农民利益、水情自动测报系统与城镇化建设和水情自动测报系统与监管统计,指出水情自动测报系统存在的问题,并提出改进拱赫  相似文献   
410.
Tetramethylarsonium has for the first time been identified in a commercially grown food product, rice, constituting up to 5.8% of the total arsenic in the rice.  相似文献   
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