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1.
Environmental Science and Pollution Research - A novel composite (nZVI/Pd-AC) was prepared by loading nanoscale zero-valent iron (nZVI) and Pd on activated carbon (AC) electrode under...  相似文献   
2.
Journal of Material Cycles and Waste Management - The traditional Chinese medicinal plant Magnolia officinalis has a wide range of applications; including more than 200 kinds of patented Chinese...  相似文献   
3.
The article puts forward the process and means of regional water and land balance research, and then from two scenarios which are the balances under natural regulation and human intervention, calculated and analysed the balance between water and land on Ningxia Plain. For the balance under natural regulation named farmland water balance, using farmland water resource balance equation, the research estimated the monthly farmland" water balance of 8 major crops for all of the 12 counties on Ningxia Plain in the period of 1960-2001; for the balance under human intervention, the research estimated land-use water balance equation of the counties in 2000, and calculated the balance between land use and water resources including irrigating water of all the 12 counties on Ningxia Plain. Results showed that ①precipitation can not meet the water demand of the crops for growth and development on Ningxia Plain, and water shortage is the primary character of farmland water balance under natural regulation. ②the diversity of water and land balance of different counties is distinctly influenced by the crop structure, water quantity for irrigation and irrigation level. ③Irrigation water could meet the crop water demand on Ningxia Plain in 2000, but there was not much space to expand irrigating cultivated land.  相似文献   
4.
本文运用系统科学原理阐释了社会和谐的内涵,指出社会和谐须以人与自然和谐为基础,以人与人之间的平等、友爱和同合作为表征,其构建与实现应遵从人类社会的演化规律,依赖予在把握人类社会需求演绎、协同人与自然关系的基础上推动生产力的高效有序发展和自然资源、生态环境的可持续支持.进而从可持续发展角度,提出了人与自然和谐的"双剩余理论",以揭示其间的供瓣枧理和协同准则;推导出了社会收益分配的相对公平系数,以衡量人与人公平要求下的社会和谐.针对国情和战略目标要求,提出了以加强小城镇建设为轴心的城市、小城镇与农村人流、物流、财流和信息流合理聚散的"三元结构"发展模式,以促进我国和谐社会的建设和可持续发展战略的有序实践.  相似文献   
5.
搞好生态建设,转移农村剩余劳动力   总被引:1,自引:0,他引:1  
大量闲置劳动力会造成巨大生态压力,加剧生态退化,但只要转移消化得当,便能化为强大的力量和优势。本文从区域→行业→企业→家庭→生态建设联合体五个层次和角度,对各种有效的和有可能的转移消化闲置劳动力生态建设途径进行了探索。  相似文献   
6.
/ Why are some environmental risks distributed disproportionately in the neighborhoods of the minorities and the poor? A hypothesis was proposed in a recent study that market dynamics contributed to the current environmental inequity. That is, locally unwanted land uses (LULUs) make the host communities home to more poor people and people of color. This hypothesis was allegedly supported by a Houston case study, whereby its author analyzed the postsiting changes of the socioeconomic characteristics of the neighborhoods surrounding solid waste facilities. I argue that such an analysis of postsiting changes alone is insufficient to test the causation hypothesis. Instead, I propose a conceptual framework for analysis of environmental equity dynamics and causation. I suggest that the presiting neighborhood dynamics and the characteristics of control neighborhoods be analyzed as the first test for the causation hypothesis. Furthermore, I present theories of neighborhood change and then examine alternative hypotheses that these theories offer for explaining neighborhood changes and for the roles of LULUs in neighborhood changes. These alternative hypotheses should be examined when analyzing the relationship between LULUs and neighborhood changes in a metropolitan area. Using this framework of analysis, I revisited the Houston case. First, I found no evidence that provided support for the hypothesis that the presence of LULUs made the neighborhoods home to more blacks and poor people, contrary to the conclusion made by the previous study. Second, I examined alternative hypotheses for explaining neighborhood changes-invasion-succession, other push forces, and neighborhood life-cycle; the former two might offer better explanation.KEY WORDS: Environmental equity and justice; Locally unwanted lane uses; Siting; Market dynamics; Invasion-succession; Neighborhood changes  相似文献   
7.
Environment, Development and Sustainability - The PPP mode of rural water environment governance was conducive to attracting social capital for giving full play to the decisive role of the market...  相似文献   
8.
通过对24个飞灰样品的重金属全量消解和高精度X射线荧光光谱法(HDXRF)快速检测结果进行线性回归分析,发现HDXRF法可较准确测定飞灰中Cu、Pb、Zn、Ni和Cd含量(线性回归决定系数R230.90).采用HDXRF法对某焚烧厂飞灰重金属含量6个月快速检测及浸出毒性测定数据统计分析发现:飞灰重金属月均含量较稳定(变异系数CV<0.14)但日均含量波动较大(CV>2.54);飞灰中Pb、Cu和Zn含量呈正相关(相关系数r>0.78);金属浸出浓度受浸出液终点pH值影响显著,超标频率依次为Pb(68.9%)、Cd(66.1%)、Ni(24.0%)、Cu(14.2%)和Zn(1.6%).短期飞灰金属含量和浸出毒性数据受焚烧工况,烟气处理工况和垃圾组分等多种因素共同影响,不具有代表性.为评估垃圾分类源头削减重金属效果,建议采用快速检测方法对焚烧飞灰重金属含量进行长期监测.  相似文献   
9.
土壤淋洗废液中污染物的选择性去除是实现淋洗液回收的关键.本文以硫化钠(Na2S)、乙基黄原酸钾(PEX)、二甲基二硫代氨基甲酸钠(DTC)作为重金属沉淀剂处理电子垃圾污染土壤模拟淋洗废液,在筛选出Na2S作为理想重金属沉淀剂的基础上,研究初始pH值、反应温度、沉淀剂浓度等因素对Na2S分离络合态重金属的影响,并通过软件模拟和产物表征等方式推测反应机理.结果表明:Na2S对柠檬酸络合态重金属的分离顺序依次为Cu、Pb、Cd,符合硫化物溶度积原则;反应温度、初始pH值对Na2S处理络合态重金属无显著影响,重金属去除率均保持在90%以上,柠檬酸的回收率约为95%;Visual MINTEQ模拟结果显示,S2-投加前液相中重金属主要以H2CA-、HCA2-和CA3-结合形式存在,S2-投加后液相中重金属则以HS-和S2-结合形式存在;扫描电镜及能谱(SEM-EDS)表明,S2-与金属阳离子按物质的量比1:1生成硫化物沉淀物,沉淀主要呈团聚、成簇和圆片状存在;X射线衍射(XRD)分析结果表明,沉淀产物中存在CuS、CdS、PbS和CuPbS2.本研究结果可为化学沉淀法处理重金属污染土壤淋洗废液提供技术参考.  相似文献   
10.
Plants constitute a major element of constructed wetlands(CWs).In this study,a coupled system comprising an integrated vertical flow CW(IVCW) and a microbial fuel cell(MFC) for swine wastewater tre atment was developed to research the effects of macrophytes commonly employed in CWs,Canna indica,Acorus calamus,and Ipomoea aquatica,on decontamination and electricity production in the system.Because of the different root types and amounts of oxygen released by the roots,the rates of chemical oxygen demand(COD) and ammonium nitrogen(NH_4~+-N) removal from the swine wastewater differed as well.In the unplanted,Canna indica,Acorus calamus,and Ipomoea aquatica systems,the COD removal rates were 80.20%,88.07%,84.70%,and 82.20%,respectively,and the NH_4~+-N removal rates were 49.96%,75.02%,70.25%,and 68.47%,respectively.The decontamination capability of the Canna indica system was better than those of the other systems.The average output voltages were 520±42,715±20,660±27,and 752±26 mV for the unplanted,Canna indica,Acorus calamus,and Ipomoea aquatica systems,respectively,and the maximum power densities were 0.2230,0.4136,0.3614,and0.4964 W/m~3,respectively.Ipomoea aquatica had the largest effect on bioelectricity generation promotion.In addition,electrochemically active bacteria,Geobacter and Desulfuromonas,were detected in the anodic biofilm by high-throughput sequencing analysis,and Comamonas(Proteobacteria),which is widely found in MFCs,was also detected in the anodic biofilm.These results confirmed the important role of plants in IVCW-MFCs.  相似文献   
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