电除尘器电源交流分量对PM_(2.5)等细微颗粒物除尘效率的影响

除尘器对颗粒物的除尘效率与颗粒物的荷电量密切相关,PM2.5等细小颗粒物由于其荷电量不足而导致其吸收效率较低,对环境造成危害。为了增加粒子的荷电量,以粒子荷电原理为理论依据,从离子电流密度和通过电凝并扩大尘粒中位径2个方面研究了电除尘电源中交流电压分量对PM2.5等细小颗粒物荷电特性的影响,得出了电除尘器电源中交流电压分量可从以上2个方面提高装置对PM2.5等微小颗粒物的荷电量,且频率越高,幅值越大,荷电效果越好,从而可以提高装置对细小颗粒物的除尘效率。     

Effects of Fireplace Use on Forest Vegetation and Amount of Woody Debris in Suburban Forests in Northwestern Switzerland

Urban forests are popular recreation areas in Europe. Several of these temperate broad-leaved forests also have a high conservation value due to sustainable management over many centuries. Recreational activities, particularly the use of fireplaces, can cause extensive damage to soil, ground vegetation, shrubs, and trees. Firewood collection depletes woody debris, leading to a loss of habitat for specialized organisms. We examined the effects of fireplace use on forest vegetation and the amount of woody debris by comparing disturbed and control plots in suburban forests in northwestern Switzerland. At frequently used fireplaces, we found reduced species densities in the ground vegetation and shrub layer and changes in plant species composition due to human trampling within an area of 150–200 m². Picnicking and grilling also reduced the height and changed the age structure of shrubs and young trees. The amount of woody debris was lower in disturbed plots than in control plots. Pieces of wood with a diameter of 0.6–7.6 cm were preferentially collected by fireplace users. The reduction in woody debris volume extended up to a distance of 16 m from the fire ring, covering an area of 800 m² at each picnic site. In order to preserve the ecological integrity of urban forests and to maintain their attractiveness as important recreation areas, we suggest depositing logging residues to be used as firewood and to restrict visitor movements near picnic sites.     

Public participation in municipal solid waste source-separated collection in Guilin,China: status and influencing factors

Currently, China is facing critical problems regarding the management of municipal solid waste (MSW). The failure of existing pilot programs in implementing MSW source-separated collection highlights the need to analyze the factors significantly influencing public participation in this activity. To this end, a comprehensive analysis of MSW source-separated collection in Guilin, which is representative of wider areas located in inland China and with a GDP around the national average, was conducted. The research consisted of in-person interviews involving a questionnaire and theoretical analyses in terms of public perception, public awareness, public attitude, and willingness to pay. The analytical results identify the status of waste source-separated collection and influencing factors in implementation, and provides exercisable suggestions for decision makers in both China and more generally in industrializing countries to design promotion programs and education campaigns.     

基于Monte-Carlo方法的静电除尘器除尘效率

针对经典除尘效率未考虑诸多随机因素影响的问题,提出了基于Monte-Carlo方法的效率分析模型,并通过实验数据验证其可靠性。通过该模型分析了粒径大小、电场气流速度、电晕电压、两极间距、粒子浓度等因素对收尘效率的影响规律,结果表明:基于Monte-Carlo方法的仿真结果精度更高,能有效预测静电除尘器的收尘效率,对于改进静电除尘器设计具有一定的理论意义和实用价值。     

再生资源产业发展的战略思考与对策建议

再生资源产业对于破解我国资源环境约束、推动新型城镇化建设和促进产业结构调整具有重要的支撑作用.但是我国再生资源产业处于发展初期,面临管理体系不善、技宋鬟备落后、产业规 缺位和产业政策不清等突出问题.对此,提出六点具体建议,包括：加强立法和产业发展的顶层设计,构建再生资源高效回收体系,推动技术装备升级和推广,完善配套财税政策,强化产业规划统筹和部门政策衔接,加强与新型城镇化建设的融合等.     

Using LCA to evaluate impacts and resources conservation potential of composting: A case study of the Asti District in Italy

Separate collection of municipal solid waste has overcome the 50% threshold in the Asti District in northern Italy, nearly one-third being composed of household and green organic waste. In order to address present and future solutions, it becomes therefore fundamental to assess the environmental performances of the current management of organic waste from separate collection. A from-gate-to-cradle life cycle assessment (LCA) model has been developed by expanding system boundaries, in order to carry out the assessment in the context of the whole waste management streamline. The environmental performances of an existing aerobic plant were made available, based on field measured data, by paying attention to the role and contribution of waste management subsystems. The need for actual and reliable data on materials and energy input, as well as gross and net gains from materials recovery, including benefits arising from use of compost in farming activities, was probably the major drawback that had to be faced. The study integrated the findings of different investigations from the literature with field measured data in order to obtain a more comprehensive framework representative of the area under study. The results may help public administrators to better understand the suitability of using LCA tools when dealing with solid waste management strategies.     

Determination of Water-soluble Atmospheric Aerosols Using Ion Chromatography

A field study was established to investigate the chemical composition of atmospheric aerosols in Chicago, IL. One goal of this study was to determine the influence of precursor trace gases and local meteorology on concentrations of secondary aerosol ionic species. This paper describes the method details, shows the method is analytically valid, and reports overall as well as some specific results found during the field study. Two particulate air samples were collected per day onto quartz fiber filters at the Loyola University Chicago Air Station during the summer months in 2002–2004. In parallel, mixing ratios of ozone and nitrogen oxides were monitored and weather parameters were recorded. Particulates were extracted from the filter substrates and the subsequent solutions were analyzed by ion chromatography for anions, including low molecular weight organic acids, and cations. A washing procedure was implemented to reduce the high background values of the quartz fiber filters. Method validation showed that the collection method was efficient for all ions with exception of nitrate, whose efficiency of 70% indicated losses caused by volatilization. The extraction method also proved efficient for both field and laboratory samples, and the repeatability of the method was high with relative standard deviations less than 10% for all ions. Reproducibility of the results was determined by comparison of sulfate to sulfur analyzed by total reflection X-ray fluorescence spectrometry and proved to be high as well. Concentrations differed significantly between the three summer studies due to varying levels of precursor species as a consequence of distinct temperatures and wind direction profiles.     

大气监测仪器维护检修能力的评价

一直以来,环境大气监测的数据精度与维护成本,始终是数据应用部门和数据提供部门的难题之一.作者谷学先生根据多年的实档践,首次提出,运用数据对大气监测仪器维护管理进行评价的可行性,并试图建立仪器维护管理作业量化的评价系统.在仪器维护管理中,任何时候,都很难完全排除技术水平比较低的仪器维护检修人员,为了回避这种实际情况,作者通过对数字的分析指出,急需构建环境大气监测仪器维护管理业务能力的评价系统,并期待地方自制体通过评价手段,来选择和指导监测仪器维护管理人员.从而提高数据的精度和减低运转经费的开支.     

对“十五”地震重点项目档案工作的探讨

“十五”期间，重点项目档案管理工作成为地震档案管理工作的重要组成部分，重点项目档案形成周期长，数量大，知识密集、覆盖面广，科技含量高，给档案的收集、归档造成一定的难度。为了加强重点项目档案的管理工作，提高归档质量，要采取切实可行的措施，保证重点项目档案的完整、准确、系统，为防震减灾事业服务。     

戴明循环理论在规划环评工作程序中的应用初探

通过分析现阶段我国规划环评的现状和存在的问题，结合国内外规划环评及其工作程序的研究成果．提出使用戴明循环理论对现阶段的规划环评工作程序进行改进，使程序层次化、工作细分化，增强整个规划环评工作的可操作性．使规划环评工作落实到单位和人，明确责任，减少部门间冲突。戴明循环理论的引入．提高规划环评的评价效果和效率．为规划环评提供了一个有效科学的评价方法，有助于规划环评的顺利开展，使环境问题从源头上得到控制．适应建设和谐社会的需要。