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941.
在对广西当前环境形势以及"十二五"时期饮用水水源地保护问题识别的基础上,结合广西全面建设小康环境新要求,提出了"十三五"饮用水水源保护规划体系以及规划目标的设想,并从保护红线、面源治理、点源治理、环境监测、信息公开5个方面给出了基本的策略建议,可为制定广西"十三五"环境保护规划目标和重点任务提供参考。  相似文献   
942.
根据2015年上半年山西省11个地级市PM 2.5、PM 10、NO 2、SO2、CO、O 3的日污染浓度监测数据及AQI值,分析其污染特征。结果表明:全省11市PM 2.5、PM 10超标率较高;NO 2、SO 2、CO、O 3超标率则较低;全省PM2.5/PM1 0的比值范围在0.367 7~0.718 9,且PM 2.5和PM 10之间存在较显著的线性关系;PM 2.5、PM 10、NO 2、SO 2、CO以及AQI监测值在1~6月份逐渐递减,O3则呈总体上升趋势;AQI达标天数比例范围在61.88%~85.08%,平均比例为71.42%,平均超标天数比例为38.58%,其中重度及以上污染天数比例为1.50%。  相似文献   
943.
收集"十二五"期间重金属污染事件网络媒体报道的重要案件,从由重金属引起的人体健康事件、食品安全事件和突发环境事件为切入点,分析媒体报道中反映出的重金属污染防治工作仍存在的问题。在此基础上,从污染源治理、信息公开、环境监管、企业主体责任、协作机制和环境健康管理的角度,提出"十三五"重金属污染防控建议,为"十三五"相关部门推进重金属污染防治管理和决策提供参考。  相似文献   
944.
沈阳市冬季一次典型大气污染过程特征和成因分析   总被引:1,自引:1,他引:0  
2013年11月18日~25日沈阳地区出现一次典型空气污染过程。采用单颗粒气溶胶质谱仪(SPAMS),并结合气象条件分析了该次污染的成因和细颗粒物的污染特征。结果表明,不利于污染物扩散的气象条件是重污染发生的主要原因,低空排放的积累可能是造成这次污染的又一重要原因。从细颗粒物成分上看,污染过程中有机碳颗粒占比明显增加,有机物污染较为严重,颗粒物间混合加剧;从来源上看,机动车尾气、工业排放和燃煤的占比较高。  相似文献   
945.
梳理了铊的特性分布、毒性危害以及我国发生的铊中毒或污染事件,分析了我国现有环境质量标准、排放标准以及监测分析标准与方法,提出了我国铊污染防治的对策建议。  相似文献   
946.
PEM water electrolysis is one of the most efficient methods for the production of hydrogen because of produced high purity of the gases and environmentally friendly. In the present study, Phosphorus-doped Graphene (PG) was synthesized by thermal annealing of triphenylphosphine (TPP) and graphene oxide (GO). The PG supported palladium (Pd/PG) electrocatalysts were synthesized by chemical reduction method and used as the cathode for hydrogen evolution reaction (HER) electrode. Structural properties and electrochemical performances of the synthesized Pd/PG electrocatalyst were studied by FE-SEM, EDS, ICP, FT-IR, XRD, and Cyclic voltammetry (CV) methods, respectively. The membrane electrode assemblies (MEA’s) were fabricated using Pd/PG as cathode for HER electrode and RuO2 as anode for OER electrode. Also, their electrochemical performances along with the corresponding hydrogen yields were evaluated in single cell PEM water electrolyzer at various experimental conditions such as different current densities from 0.1 to 2.0 A cm?2 and temperatures (28–80°C). The synthesized Pd/PG electrocatalyst was observed a current density of 1 A cm?2 with 1.95 V at 80°C. Further, long-term stability studies were carried out continuously up to 2000 h which showed a reasonable stability. Hence, the synthesized Pd/PG can be used as an alternative to Pt-based electrocatalysts for the HER in PEM water electrolysis.  相似文献   
947.
Factors affecting population recovery from depletion are at the focus of wildlife management. Particularly, it has been debated how life‐history characteristics might affect population recovery ability and productivity. Many exploited fish stocks have shown temporal changes towards earlier maturation and reduced adult body size, potentially owing to evolutionary responses to fishing. Whereas such life‐history changes have been widely documented, their potential role on stock's ability to recover from exploitation often remains ignored by traditional fisheries management. We used a marine ecosystem model parameterized for Southeastern Australian ecosystem to explore how changes towards “faster” life histories might affect population per capita growth rate r. We show that for most species changes towards earlier maturation during fishing have a negative effect (3–40% decrease) on r during the recovery phase. Faster juvenile growth and earlier maturation were beneficial early in life, but smaller adult body sizes reduced the lifetime reproductive output and increased adult natural mortality. However, both at intra‐ and inter‐specific level natural mortality and trophic position of the species were as important in determining r as species longevity and age of maturation, suggesting that r cannot be predicted from life‐history traits alone. Our study highlights that factors affecting population recovery ability and productivity should be explored in a multi‐species context, where both age‐specific fecundity and survival schedules are addressed simultaneously. It also suggests that contemporary life‐history changes in harvested species are unlikely to increase their resilience and recovery ability.  相似文献   
948.
在中国经济高增长的背后,环境污染问题愈发凸显,不利于经济的可持续增长。税收竞争是影响环境污染的主要因素之一,但是学术界研究税收竞争对环境污染的影响及其作用机制的较少。本文按照污染物属性将其划分为外溢性污染物和非外溢性污染物,通过构建一个包含生产者、消费者、地方政府及中央政府的一般均衡模型,刻画了在税收竞争的背景下,地方政府的税收征管效率对不同属性污染物的影响及其传导机制。结果发现当污染物具有外溢性属性时,税收征管效率对该地环境污染的影响通过改变本地及周边地区资本存量渠道实现;当污染物具有非外溢性属性时,降低税收征管效率通过增加该地区资本存量而提高了环境污染。文章首先使用随机前沿模型测算了2007—2014年中国28个省份企业所得税的税收征管效率,并将其作为税收竞争的衡量指标,然后运用系统GMM法证实了所提的假说。研究显示:地方政府的税收竞争增加了本地区的资本存量;税收竞争是将本地资本存量作为其推高外溢性污染物(二氧化硫)及非外溢性污染物(固体废弃物)排放量的一个主要渠道,邻近地区资本存量则是推高外溢性污染物(二氧化硫)的次要渠道。这意味着,要想改善环境质量,中央政府应规范地方政府的税收竞争行为,尽快建立一套科学、有效的绿色GDP评价体系;完善地方转移支付制度;应针对各个地区的污染及经济发展情况利用财政激励手段引入环保、绿色的资本项目;地方政府应减少不利于环境改善的地方财政支出,增加环保投入比重。  相似文献   
949.
The Massachusetts’ Toxics Use Reduction Act (TURA) of 1989 set an important milestone in the roadmap to Clean Production. The Act’s focus on a clear definition, methodology, and mandatory planning requirements have proved successful in getting companies in Massachusetts to reduce their use of toxic chemicals in manufacturing processes. Such results are inspirational for government officials and advocacy groups attempting to reduce toxic emissions in their communities and set progressive chemicals use policies. This paper will summarize three initiatives where TURA was a catalyst and continues to impact international chemicals policy: the Sewer Use By-law in Toronto, Canada; the European Union’s REACH chemicals legislation and the international campaign by Greenpeace in Asia and Latin America to achieve zero discharge of hazardous substances into rivers. The example of Toronto and REACH show how one or more essential aspects of TURA were incorporated into legislation. In the case of REACH TURA’s requirement of mandatory planning became an important example and NGO demand during the formation of Europe’s new chemicals regulation and resulted in the first substitution assessment planning requirement in EU wide legislation. Work is now ongoing to promote TURA type legislation in Latin America and Asia. However the ability to transfer the TURA framework to regions with inadequate government oversight and cheap disposal costs is seriously hampered. Although NGO campaigns in Asian and Latin America advocate zero discharge of hazardous emissions through toxics use reduction and elimination, much training and accountability will be needed within government and companies to understand the benefits of toxics use reduction and actually implement all or parts of the TURA framework. The Toxics Use Reduction Act came into force in 1989 with high environmental awareness, an engaged citizenry and a responsive government entity. Perhaps these are the same conditions that must exist for its successful transference to industrializing countries.  相似文献   
950.
Ship breaking or recycling in Bangladesh has been a catalyst for the economy by supporting the steel, shipbuilding, furniture, building construction, machinery and electrical industries since the 1980s. Although it has generated huge employment and provided 80–90% of the total steel consumption in the country, it has faced a host of challenges due to a number of negative environmental and social impacts that hinder the sustainable development of this blooming sector. The objective of this paper is to focus on how ship-breaking activities in Bangladesh affect the adjacent environment and the health and safety of workers, as well as management’s approach to the sustainability of the industry, by conducting a review of the available scientific literature. We found that grave environmental pollution, such as physiochemical properties, heavy metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyl compounds (PCBs), organotins, oil and grease pollution, asbestos and other atmospheric pollutants, and its impact on marine ecosystems, biodiversity, forestry, fisheries and human health are the main obstacles for the development of a sustainable ship-breaking industry. In addition, labour safety and occupational health problems, social unrest and conflicts have resulted from the development of the ship-breaking industry in Bangladesh. Inappropriate management practices and inadequate plans regarding ship-breaking activities and processes are the main reasons for these challenges. Effective management measures to mitigate the adverse environmental impact of the ship-breaking industry and to improve the health and safety of workers have now become an urgent requirement.  相似文献   
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