全站仪圆弧参考线测量在南水北调工程中的应用探讨

随着我国各项基础建设的快速推进以及全站仪的普及,如何充分发挥仪器内固有程序的作用,是每个使用者所关心的问题。文章以南水北调中线漕河段界河倒虹吸延长工程数据为依托,结合多年的实际工作经验,详细探讨了圆弧参考线测量在南水北调工程中的使用方法,并且在精度上给予评定,结果显示完全符合工程规范要求。     

USING LEGISLATION TO REDUCE ONE‐TIME PLASTIC BAG USAGE

Plastic bag litter generates serious environmental concerns and poses a risk to wildlife. As this does not seem to be a problem which can be resolved by the private sector alone, or by ‘Coasean’ negotiation, legislation is proposed, particularly focusing on ‘one‐use’ bags. This article surveys legislation worldwide, while concentrating on lessons from the United States and the United Kingdom. The issues are more complex than is often assumed. While environmentalists argue for restriction and ultimate elimination of one‐use bags, manufacturers, especially those that have reformulated the composition of their bags, see legislation as an overreaction to a problem that is already being addressed within the industry. They cite evidence that, when used within a comprehensive recycling programme, plastic bags are not only cost‐effective but a sound use of our limited resources. Bans or restrictions can have knock‐on effects which can create new problems.     

基于水权交易和面源污染控制的农户灌溉施肥行为模型

将水权交易和面源污染控制有机结合,以种植面积、农业用水定额、污染物浓度为约束条件,运用边际分析方法建立农户灌溉施肥行为模型,分析水权交易和排污控制对农户行为的影响。结果表明:灌溉用水量与农作物价格成正相关,与交易水价和边际灌溉成本成负相关;一定范围内肥料施用量与农作物价格成正相关,与边际施肥成本或边际环境成本成负相关。模型证明,当农业用水定额内水权可交易时,水市场的存在和水价政策将激励农户减少灌水量,节约用水。     

基于污染物通量超标排放的生态补偿方法

针对污染物通量核算生态补偿量方法中单位污染物削减成本忽略了污染物来源差异性以及污染物通量核算未考虑年内实际水文、水质特征的问题,从污染物削减成本和污染物通量两个方面对该方法进行改进。污染物削减成本按照污染物来源分为点源污水(主要为工业废水、城市生活污水)和农村非点源污水(主要为农村生活污水、农业生产污水)削减成本两部分,根据不同废水来源的处理成本,按污染物排放量比重加权平均得到削减成本;同时,对年内划分水期,分别核算污染物通量。选取沱江支流上的濑溪河渝川缓冲区进行实例验证。结果表明:核算结果基本能够反映区域污染特征,核算金额也更加真实可信。     

Politics of The Ring: Limits to Public Participation in Engineering Practice

How engineering in the context of urban socio‐environmental challenges is practically and effectively mobilized has been the subject of some debate. Numerous professional bodies have encouraged engineers to approach socio‐environmental issues through increased engagement with, and accountability to, the public through effective participatory practices. This article presents a close empirical analysis of a major engineering project in London to argue that engineering has a more complex relationship with social, political and environmental conditions than the idealistic participatory conception supposes. In fact, the spatial, technical and economic arrangements of engineering practice may limit the potential for public participation. Through a detailed analysis of the example of the London Water Ring Main (from around 1988 to 1994), this article shows how myriad sometimes conflicting engineering issues and responsibilities interfered with key elements of effective participation. Therefore, although increased public engagement in engineering may be desirable in theory, substantial professional, institutional and political change may have to occur before this is possible in practice .     

高校化学实验室几种废液的处理方法探索

高校化学实验室产生的废液不经处理便直接排入下水道,势必给环境和人类健康带来较大危害。针对这些问题,文章探索了几种方法对废液进行简单有效的处理和回收。     

城市供水的二次污染原因及治理

自来水经过一定的处理工艺,然后经过配送管网输送至各户。水在配送管网中流动的过程中,往往会受到管网、供水管道及附属设备的影响,造成二次污染。因此,要切实做好城市供水二次污染的防治工作,提高人们的生活质量。基于此,本文提出了城市供水二次污染的几点原因和一般性的治理对策。     

浅议建筑给排水实验教学的研究意义

文章通过跟踪调查实际教学中的《建筑给排水》课程,研究和寻找建筑专业课程在探究型教学模式下的应用和效果,对教学中的问题进行分析,提出适合专业教学的方法,并就如何更加完善《建筑给排水》的教学模式进行讨论。     

机动车尾气污染危害的生成机理与治理发展

本文介绍了汽车尾气对人类健康和生态环境的危害,及其生成机理和影响因素并简述汽车尾气治理与发展。     

土壤污染防治法背景下的城乡绿地系统建设：趋势与对策

《中华人民共和国土壤污染防治法》的颁布标志着中国将形成完善的土壤污染防治法律体系，建立从污染土壤调查、修复、风险防控、监测到场地再利用，从环境标准到规划管理的全方位制度。生态文明制度建设的宏观背景，再加上中国土壤污染严重、规模大、修复难、成本高、周期长等特征，将导致大量污染场地转变为绿地或生态用地，最终对绿地系统的数量与规模、布局与功能、规划与管理、环境质量标准等多个维度产生实质性影响。分析这一趋势，对其影响提出预判，最终提出对策建议。