Effect of soil solids concentration in batch tests on the partition coefficients of organic pollutants in landfill liner-soil materials

 The effect of the soil solids concentration in batch tests on the measured values of the partition coefficient (K _p) of organic pollutants in landfill liner-soil material was investigated. Since this study was based on the results of batch and column tests conducted independently, there were limitations to the conclusions derived. The organic compounds tested were benzene, methylene chloride, toluene, trichloroethylene, and p-xylene. The results of this study showed that as soil solids concentrations increased, the measured K _p values of these organic compounds strongly decreased. The observed values of K _p stabilized when the soil solids concentration was above a certain value. Typical K _p values obtained from batch tests conducted under high soil solids concentrations were close to those obtained from column tests. It was concluded that the K _p values of organic compounds measured under low soil solids concentrations, i.e., less than 100 g/l, may not correctly simulate the field situation. Consequently, the values of K _p obtained with low soil solids concentrations can result in an overestimation of the retardation factor of the landfill liner material. Received: March 14, 2002 / Accepted: August 25, 2002     

The Relation Between Sandstorms and Strong Winds in Xinjiang,China

With observational data spanning 1961–1999 from 90 meteorological stations in Xinjiang, China, the spatial and temporal characteristics of sandstorms and strong winds, and the contribution of strong winds to the occurrence of sandstormsare analyzed. Moreover, the dominant wind direction and minimumwind speeds during sandstorm periods are discussed. The research shows that although possessing similar climatic trends, sandstorms and strong winds in Xinjiang have opposite geographical distributions, i.e. places with more sandstorms show fewer strong winds. The contribution of strongwinds to sandstorms in northern Xinjiang is larger than that insouthern Xinjiang. The dominant wind directions clearly indicatethe paths of the weather systems that introduced the sandstorms.The minimum wind speeds in the sandstorms were over 10 ms^-1in northern and eastern Xinjiang and in the Turpan and Yanqi Basins of southern Xinjiang. In Tarim Basin of southern Xinjiang,however, the minimum wind speed was about 6–8 ms^-1, and even 6 ms^-1 at its southern edge.     

SPATIO-TEMPORAL CHANGE OF DROUGHT DISASTER IN CHINA IN RECENT FIFTY YEARS

Foreword　Inglobalview ,droughtdisasterisregardedasthemostserioustypeofnaturaldisasterintheworld ,whichhascausedthewidestrangeofeffectsandthebiggesteconomiclosses .Se veredroughtsmainlyoccurinAfrica ,India ,China ,formerSovietUnion ,NorthAmerica ,andAustralia,accountingforalmosthalfofcountriesintheworld .Droughtdisasteroccursfre quentlyinChina ,withwiderangeofinfluence ,whichisthemostseriousmeteorologicaldisas ter ,causingeconomiclossesinagriculture .Fromthe 50’stothe 80’sinthe 2 0thcent…     

师范高等专科学校开展环境教育的实践与研究

本文论述了在师专开展环境教育的意义和多维功能作用。总结了乐山师专长期肾开展环境教育的经验和特点，对全面提高学生素质，培养中学教改急需的环境教育师资具有重要的现实意义。     

洗涤法处理含油土壤的研究

研究了用洗涤法处理含油土壤，考察了洗涤剂种类与浓度、洗涤温度、液固比、洗涤时间、表面活性剂、洗涤液直接循环使用次数对洗涤效果的影响，结果表明：当混合减浓度为10000mg／L、洗涤温度为70℃、液固比2：1、洗涤时间20min时，可将含油量为30％的土壤洗至残油率仅为0．3％左右。OP、EL型表面活性剂的加入对洗涤效果没有改善，特别有意义的是洗涤液能够直接循环使用而对洗涤效果基本无影响，这不仅能够减少用水量，还可以大大减少废水的排放量，降低操作费用及废水处理费用。该洗涤法不涉及物质的相变过程，混合碱由廉价的无机碱和无机盐组成，故能量消耗低，处理费用也低，且洗脱下来的原油可回收。     

填料式浮选柱操作参数的研究

在实验室装置上研究了不锈钢波纹板填料柱的主要操作参数对除油率的影响。研究结果表明：填料可以明显改善气体在柱内的径向分布，可以明显提高浮选柱的操作稳定性。实验确定了波纹板填料式浮选柱的主要操作参数是：最低气体表现线速度3．8cm／s，污水停留时间为5min，浮选剂投加量为5～10mg／L。     

大庆地区水体环境的水生生物调查结果与评价

结合区域工业污染源的构成特点，对分布在油田的13个湖库进行了浮游生物和底栖动物的调查，从生物学角度，科学地评价了各类水体的污染程度，为保护和合理开发利用地表水资源，污染源的优化管理，实现污染物的总量控制提供了科学依据。     

东部油田采出污水处理的长远对策

从综合治理，合理利用采出污水的长远利益出发，针对东部油田高含水阶段的新特点，提出地面高效处理，地下控水稳油相结合的治理策略，探讨了相关的技术和方法，并讨论了采出污水回注利用中应加强研究的几个问题。     

环境医学：人类生存发展战略的大课题

文章用大量翔实数据，分析论证：人类由于淡化环境意识，坚持急功近利的片面发展观，造成整个地球环境质量正在全面下降和恶化，全球已有１／５的人口受到环境污染之害的基点上，作者提出了只有跳出以自我生存为中心的狭隘圈，确立发展环境医学为主体的预防医学战略，并提示要遵循中国古代强调的“天人合一”论概念和钱学森提出的“开放的巨系统方法论”在当代科技领域进行“天地生人巨系统的综合集成研究”，树立“天地与我并生，万物与我同运”的自然生态观，为创建“生物心理社会自然”为模式的全科新医学，这是实现２１世纪“人类健康工程”的开拓性目标。     

城市垃圾甲烷气体排放及减排对策

本文讲述了城市垃圾的现状以及影响垃圾甲烷排放的各种因素，并根据ＩＰＣＣＧｕｉｄｅｌｉｎｅｓ（１９９５）提供的方法对１９９０～２０１０年江浙沪地区城市垃圾甲烷排放量的变化趋势进行了预测统计计算，１９９０年江浙沪地区城市垃圾甲烷排放量为７１２３万吨，２０１０年预测的甲烷排放量为２６６７６万吨，本文就垃圾中甲烷的排放提出了切实可行的减排方案。