Dechlorination of carbon tetrachloride by the catalyzed Fe-Cu process

The electrochemical reduction characteristics of carbon tetrachloride (CT) were investigated using cyclic voltammetry in this study. In addition, the difference in reduction mechanisms of CT between Master Builders' iron and the catalyzed Fe-Cu process was discussed. The results showed that CT was reduced directly on the surface of copper rather than by atomic hydrogen produced at the cathode in the catalyzed Fe-Cu process. The reduction was realized largely by atomic hydrogen in Master Builders' iron. The entire CT in 350 ml aqueous solution with 320 mgL was reduced to trichloromethane and dichloromethane in 2.25 h when 100 g of scrap iron with FeCu ratio of 10:1 (ww) were used. Moreover, the reduction rate slowed with time. CT could be reduced at acidic, neutral and alkaline pH from solution by Fe-Cu bimetallic media, but the mechanisms were di?erent. The degradation rate was not significantly in?uenced by pH in the catalyzed Fe-Cu process; in Master Builders' iron it clearly increased with decreasing pH. The kinetics of the reductions followed pseudo-first order in both cases. Furthermore, the reductions under acidic conditions proceeded faster than that under the neutral and alkaline conditions. The catalyzed Fe-Cu process was superior to Master Builders' iron in treating CT-containing water and this advantage was particularly noticeable under alkaline conditions. The reduction was investigated in the cathode (Cu) and anode (Fe) compartments respectively, the results showed that the direct reduction pathway played an important role in the reduction by the catalyzed Fe-Cu process. The catalyzed Fe-Cu process is of practical value.     

石首天鹅洲六合垸扩大麋鹿栖息地初析

自石首麋鹿国家级自然保护区设立以来,麋鹿种群得到了有效发展。因各种因素综合作用,现有保护区已呈现容纳量不足的趋势。相较其它湿地,依据岛屿生物地理学“平衡理论,”与麋鹿保护区相连通的六合垸似乎在扩大麋鹿栖息地方面具有地理优势。文章侧重从景观学(形状、连接度、廊道构建)及社会(移民)两个角度对其优势度状况作尝试性分析,进而得出六合垸并不具有明显优势的初步结论。     

青藏高原产业发展的交通运输门槛研究

利用比较优势发展地区经济是促进地区经济增长的有效途径 ,运输条件的优劣和运输费用的高低是关键因素。众所周知 ,交通运输对青藏高原地区经济发展的影响非常突出 ,处理好产业发展与交通运输间的关系 ,有利于高原地区经济的健康发展。论文利用交通运输门槛理论 ,分析了高原地区资源开发的优势、产业发展方向以及合理的地区布局 ;提出了集中开发优势矿产 ,发展占领本地市场和开拓外部市场的优势轻工业 ,大力降低运输成本以提高产品竞争能力等观点。地域发展上 ,应采取非均衡发展的战略 ,集中发展河湟谷地、柴达木盆地和“一江两河”地区。     

城市污水处理厂污泥特性及资源化利用的发展对策

分析了中国部分污水处理厂污泥的特性。借鉴部分城市污泥处置利用的先进手段和经验，提出了中国污泥资源化利用应遵照“实事求是、因地制宜”的原则。政府提供优惠的产业政策。同时以示范工程为依托。污泥利用形成产业化．成为污水处理企业除污水处理费征收、中水回用之外的第三个经济增长点。弥补污水处理费用的不足，解决污水处理从业人员过多的问题，而且还可以充分发挥污水处理厂社会效益和生态环境效益的发展对策。     

Environmental management and firm performance: a case study

This study has as its aim to help to clarify the relationship between environmental management and economic performance by integrating it into a wider framework that includes the relationship between environmental strategy and firm performance, the latter being understood as the combination of environmental performance, competitive advantage and economic performance. A case study of the COATO farming cooperative showed us that its environmental management, focused on prevention logic, has had a positive net effect on its environmental performance. Besides, the order in which these practices were adopted favoured the development of new organisational capabilities that have contributed to the appearance of advantages derived from the greater accumulated experience of employees in creating new projects that are designed to reduce residues and pollution. COATO has also obtained a competitive advantage in differentiation thanks to an improved brand image and to its increased credibility in business relationships. Finally, a positive correlation exists between the pioneering proactive strategy adopted by this cooperative and the improvement of its firm performance with respect to the other firms in its sector.     

长江上游陡坡耕地退耕的难点与对策

长江上游属于 2 5°以上的陡坡退耕还林地面积达 170万hm2 ,是长江上游水土流失的重要策源地 ,严重制约了该区域社会经济的可持续发展。因此 ,实行陡坡耕地退耕还林是建设长江上游生态屏障的重要组成部分 ,也是生态建设的主要内容之一。本文较为系统地论述了陡坡耕地的形成原因与危害 ,以及退耕的难点与有利时机 ,并探讨了详细分析了主要对策     

区域耕地总量比较优势研究——以江苏省为例

本文将比较优势理论运用到指导耕地保护和耕地总量动态平衡的工作中 ,探索了一种较为简单、可行的计量方法 ,对江苏省三大地区 (苏南、苏中和苏北 )的耕地总量比较优势进行了测算 ,并在此基础上分析了江苏省的耕地总量区域差异 ,得到了一些政策启示。     

江苏省农业比较优势格局及与周边省市比较分析

:将江苏省置于长江中下游种植区内 ,运用国内资源成本系数DRCC(DomesticResourcesCostCoefficient)和RDRCC(RatioDomesticResourcescostCoefficients)指标考察了江苏省与周边省市 (包括上海、安徽、浙江、江西、湖北和湖南 )农业生产比较优势的差异 ,从而全面地认识了相对于长江中下游种植区六省市江苏省农业生产的比较优势格局。根据分析 ,与周边地区相比 ,江苏省秋收作物粳稻、大豆 ,夏收作物油菜籽、棉花和早籼稻 ,常年生作物茶叶生产都具有不同程度的相对比较优势 ,可考虑通过适当的政策将资源导向这些产品的生产上 ;同时重点压缩小麦、中籼稻、玉米、花生、烤烟等不具相对比较优势产品的生产。此外 ,江苏桑蚕茧可考虑稳定现有的生产 ,而苹果生产可适当调减。主要饲养业产品中 ,蛋鸡、肉鸡和淡水鱼具有相对比较优势 ,其饲养总量可以考虑进一步扩大 ,相反 ,生猪和菜羊不具相对比较优势 ,饲养规模应适当压缩。而江苏奶牛饲养总规模可考虑稳定 ,并适当扩大国营集体饲养的规模     

中国在国际贸易中的两大相对比较优势

可持续发展要求丰富与发展传统的国际贸易理论，尤其需要将环境要素纳入到现有的相对比较优势分析框架体系内。本文运用相对比较优势分析方法研究了劳动力、资本与环境要素之间的关系。结果表明近年来中国持续增长的国际贸易除了依赖中国劳动力的相对比较优势外，也依赖于中国环境的相对比较“优势”，劳动力与环境资源是中国对外贸易的两大相对比较优势。然而,随着中国劳动力成本的上升与环境污染压力的增加，这两大“优势资源”将面临严峻的挑战。     

湖北贫困地区旅游开发优势及现实意义——以鄂西北地区为例

以鄂西北地区的襄樊市、十堰市和神农架林区为例,分析了该区的区位条件和社会、经济发展态势,旅游资源特征,旅游环境现状及其开发优势,阐述了贫困地区旅游开发规划对扶贫工作的促进作用和扶贫旅游的现实意义。本区的多数县市处于山地环境,地形崎岖,交通受到限制,经济发展相对滞后,扶盆任务依然艰巨,本区旅游资源丰富多彩,有些资源的品位也很高,可以总括为“531优势”。即人文旅游资源的五大文化特点-楚国发祥地（楚文化）,三国之源（三国文化）,流放文化,道教文化,郧阳猿人（古人类文化）,形成明显的锁定效应;自然旅游资源的三大品牌－纳入“世界自然保护区网”的神农架,在国内外有一定声誉的郧县恐龙蛋化石基地,正在规划的武当山国家级地质公园,一处国家级风景名胜区－自然与人文景观相得益彰的“隆中风景名胜区”,其资源环境优势在于,自然生态优美,环境污染轻,空气质量好,气候适宜,土特产品丰富,对这些旅游资源进行科学合理的开发利用,并按照“PPT”战略实施扶贫计划,将有力促进本地区经济发展。