Kinetic study of permanganate oxidation of tetrachloroethylene at a high pH under acidic conditions

Since carbon compounds are the main component of dense nonaqueous phase liquids (DNAPLs), the end products of all in situ chemical oxidation (ISCO) will include carbon dioxide. If the production rate of carbon dioxide exceeds the capacity of water to remove the carbon dioxide, degassing will occur. The uncontrolled carbon dioxide gas may change the flow patterns, remobilize the pooled DNAPL, transport DNAPL vapor, and reduce the relative permeability to the aqueous phase. Under high pH buffered conditions, most of the carbon dioxide will be dissolved in water. In this study, potassium permanganate oxidation of tetrachloroethylene (PCE) was conducted using a sodium carbonate buffered solution (1 g/L, pH = 10.6 ± 0.1) at three different temperatures (5, 10, and 20°C) and three potassium permanganate concentrations (0.2, 1, and 5 g/L). Extensive kinetic studies suggest that the overall oxidation is a second‐order reaction and pseudo‐first‐order with respect to PCE and potassium permanganate, respectively. The second‐order rate constant and the activation energy were 0.028 ± 0.001 M^?1s^?1 at 20°C and 43.9 ± 2.85 kJ/M, respectively. This study provides a base for further experimental and field studies on potassium permanganate oxidation of PCE under natural or artificial high pH buffered conditions. © 2004 Wiley Periodicals, Inc.     

溶剂萃取法提取废旧碱性电池中的有价成分

为回收利用废旧电池，进行了溶剂萃取法提取碱性废弃电池中锌、锰金属的试验研究。选择南孚（AA）碱性废电池为处理样品，通过粉碎、水浸、酸浸等步骤，获得含锌、锰离子的稀溶液，并利用模拟体系得到的萃取结果进行浸出液的萃取性能试验研究。结果表明，每个废电池填充物中含锌和锰分别为0.25g和0.36g，具有可观的回收价值；采用完全皂化的二（2－乙基己基）磷酸（D2EHPA）／煤油为萃取剂提取含锌锰的酸浸出液，一级萃取就可获得60％以上的提取率。     

生态补偿与生态云南

构建生态云南的基本要素有：明确的责任；心理准备充分；资金充裕；社会动员、组织动员高效便捷；打环境官司容易；完善的约束——激励机制；履行生态伦理的能力。生态补偿能创造和积累构建生态云南所需要素和条件。本文将云南生态补偿划分为伦理型生态补偿和法制型生态补偿，探讨各类生态补偿的发展策略、步骤、方式和手段。     

China’s Classification-Based Forest Management: Procedures,Problems, and Prospects

China’s new Classification-Based Forest Management (CFM) is a two-class system, including Commodity Forest (CoF) and Ecological Welfare Forest (EWF) lands, so named according to differences in their distinct functions and services. The purposes of CFM are to improve forestry economic systems, strengthen resource management in a market economy, ease the conflicts between wood demands and public welfare, and meet the diversified needs for forest services in China. The formative process of China’s CFM has involved a series of trials and revisions. China’s central government accelerated the reform of CFM in the year 2000 and completed the final version in 2003. CFM was implemented at the provincial level with the aid of subsidies from the central government. About a quarter of the forestland in China was approved as National EWF lands by the State Forestry Administration in 2006 and 2007. Logging is prohibited on National EWF lands, and their landowners or managers receive subsidies of about 70 RMB (US$10) per hectare from the central government. CFM represents a new forestry strategy in China and its implementation inevitably faces challenges in promoting the understanding of forest ecological services, generalizing nationwide criteria for identifying EWF and CoF lands, setting up forest-specific compensation mechanisms for ecological benefits, enhancing the knowledge of administrators and the general public about CFM, and sustaining EWF lands under China’s current forestland tenure system. CFM does, however, offer a viable pathway toward sustainable forest management in China.     

多中心治理下公众参与大气污染防治路径探析

动员全社会力量保护环境,积极推动公众参与环保工作,是解决环境保护问题的根本途径。运用多中心治理理论分析,发现政府治污理念陈旧、制度不健全、公众责任意识淡漠、环保社会组织弱小等,是我国大气污染治理中公众参与度低的主要原因,因此提出转变观念、完善机制、加强教育、支持和引导环保社会组织,促进公众参与的多元治理模式的形成,真正推动大气环境质量的改善。     

长三角区域环境污染根源剖析及协同治理对策

当前的长三角区域环境治理尽管取得了一定成效,但其治理成本过高且难以达到持久改善的效果。长三角环境污染的根源在于投资驱动型增长导致的结构性污染锁定,以及低端经济导致的能源升级障碍。因此,环境治理应着眼于区域增长方式转型和环境与发展关系的优化,关键问题在于如何改变经济增长的推动方式与路径依赖,如何在新常态经济格局下寻求新的经济增长点,以及如何协调好不同行政区划之间的利益冲突。当前长三角区域需建立区域一体化的环境协同治理机制,推进能源升级与产业去重化进程,促进地区间错位发展与联动发展,以新型城镇化调动新的增长潜力,结合智慧城市建设转变公共服务供给方式,优化城市布局。     

An Optimization Method Based on Scenario Analysis for Watershed Management Under Uncertainty

In conjunction with socioeconomic development in watersheds, increasingly challenging problems, such as scarcity of water resources and environmental deterioration, have arisen. Watershed management is a useful tool for dealing with these issues and maintaining sustainable development at the watershed scale. The complex and uncertain characteristics of watershed systems have a great impact on decisions about countermeasures and other techniques that will be applied in the future. An optimization method based on scenario analysis is proposed in this paper as a means of handling watershed management under uncertainty. This method integrates system analysis, forecast methods, and scenario analysis, as well as the contributions of stakeholders and experts, into a comprehensive framework. The proposed method comprises four steps: system analyses, a listing of potential engineering techniques and countermeasures, scenario analyses, and the optimal selection of countermeasures and engineering techniques. The proposed method was applied to the case of the Lake Qionghai watershed in southwestern China, and the results are reported in this paper. This case study demonstrates that the proposed method can be used to deal efficiently with uncertainties at the watershed level. Moreover, this method takes into consideration the interests of different groups, which is crucial for successful watershed management. In particular, social, economic, environmental, and resource systems are all considered in order to improve the applicability of the method. In short, the optimization method based on scenario analysis proposed here is a valuable tool for watershed management.     

层次分析法与向量模法在水环境承载力评价中的应用——以胶州市为例

从社会经济、资源利用、与环境管理等角度分析了胶州市水环境承载力的主要影响因素,综合构建了胶州市水环境承载力评价指标体系。采用层次分析法和向量模法对胶州市2007~2011年水环境承载力进行了评价。结果表明,胶州市水环境承载力评价值范围为0.061~0.080,胶州市水环境承载力水平较低,总体上呈先下降后上升的趋势,其中,水资源短缺为制约胶州市水环境承载力的主要因素。     

金城造纸厂综合污水处理工程调试运行

总结了采用好氧工艺处理造纸工业废水中各个不同调试阶段及对应的工艺运行参数。该废水难生化降解,其ρ(BOD5)/ρ(COD)值在23.3%左右,而且废水中N、P等营养元素含量不足。通过投加尿素和磷酸氢二氨,使均质池TN、TP含量满足微生物生长;同时降低进水ρ(COD)值至1500mg/L,提高曝气池溶解氧量至3.0mg/L,污泥浓度至4500mg/L,将COD污泥负荷从最初0.45～0.55kg/(kg·d)逐渐下降到0.30～0.35kg/(kg·d),经过2个月的调试运行,出水各参数达到设计排放标准:COD为450mg/L、BOD5为25mg/L、pH为6.8。     

太湖沉积物中重金属污染状况及分布特征探讨

依据沉积学原理和水体沉积物重金属的环境地球化学特性，用地积累指数法和改进的多变量Chernoff脸谱图，对太湖沉积物中重金属的污染状况及不同重金属的地积累程度进行了综合性的评价。结果表明：（1）太湖沉积物中重金属的污染可划分为3个区域：湖心相对清洁区、湖岸轻度污染区和内湖综合污染区。（2）太湖沉积物中重金属存在轻度污染。其中铜污染极别高于其它金属，且集中的太湖北部地区。铬污染属于轻度污染，具有分布空间广且均衡的特点。