PESTICIDES IN GROUND WATER: DO ATRAZINE METABOLITES MATTER?1

ABSTRACT: Atrazine and atrazine-residue (atrazine + two metabolites - deethylatrazine and deisopropylatrazine) concentrations were examined to determine if consideration of these atrazine metabolites substantially adds to our understanding of the distribution of this pesticide in groundwater of the midcontinental United States. The mean of atrazine.residue concentrations was 53 percent greater than that of atrazine alone for those observations above the detection limit (> 0.05 μg/l). Furthermore, a censored regression analysis using atrazine-residue concentrations revealed significant factors not identified when only atrazine concentrations were used. Thus, knowledge of concentrations of these atrazine metabolites is required to obtain a true estimation of risk of using these aquifers as sources for drinking water, and such knowledge also provides information that ultimately may be important for future management policies designed to reduce atrazine concentrations in ground water.     

地震序列的h值快速震型判别与强余震预测

用数值拟合的方法对１９６６年以来７６个ＭＬ≥５．５地震序列的衰减特性进行了较详细的研究，提出从ｈ值的逐日时间扫描和逐日累积时间扫描两个方面去把握地震序列的衰减过程并将其用于强余震（含双震）的预测和震型的快速判定。     

灾害地图几个问题的初步研究

运用地图学的理论和方法，阐述了灾害地图的性质、内容、功能和作用，介绍了灾害地图的主要类型，探讨了灾害信息图形显示的过程、方法和手段，并提出了开展灾害地图研究的几点建议。     

土氡测量在地质灾害勘测中的干扰实验研究

对土氡勘测中来自测量过程、勘测场地条件、气象因素方面的常见干扰进行了实验研究，探讨了干扰机理，指出了定性及部分定量排除干扰的方法。     

危险货物铁路罐车安全运输中存在的若干问题及其对策

针对近年来危险货物铁路罐车在运输中屡屡发生重大事故的情况，通过现场调研和事故案例的分析，找出影响罐车运输安全的若干问题及其产生的原因、可能导致的严重后果等等，并提出解决问题的对策。     

喷射溶气回流浮选工艺处理含油废水

采用喷射溶气回流浮选工艺处理含油废水，替代原来的全加压溶气浮选工艺，提高了浮选过程的处理效果，增强了系统的抗负荷冲击能力，浮选出水油含量由原来的〈４０ｍｇ／Ｌ降至〈２０ｍｇ／Ｌ，ＣＯＤ由原来的〈１５０ｍｇ／Ｌ降至〈１１０ｍｇ／Ｌ。     

Thermal and mechanical properties of poly(lactic Acid) and poly(ethylene/butylene Succinate) blends

In this study, blends of poly (lactic acid) (PLA) with poly(ethylene/butylene succinate) (Bionolle) have been investigated for their thermal and mechanical properties as a function of the concentration of Bionolle. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and tensile tests were used to characterize the blends. From the results of the DMA and DSC, it was found that this blend system was not miscible within the compositions studied. DSC results showed that adding Bionolle aids in crystallization of PLA. It was observed that increasing the Bionolle concentration led to a slight increase in the strain-at-break of the blends but a decrease in the Young’s modulus and ultimate tensile strength. Biaxially oriented films showed an increase in tensile strength, modulus, and strain-at-break.     

煤矿人为事故发生可能性预测数学模型研究

研究发现，煤矿工人的冒险行为主要可以由生产条件、个人表现、工作状况及用工方式等影响因素预测，煤矿人为事故的发生可能性主要由煤矿工人的冒险行为表现预测。据此，便可建立预测煤矿人为事故发生可能性的数学模型     

地质勘探巷道的通风新方法探讨

探讨了巷道通风的新方法，其中包括用间断风筒的通风、半循环通风、封闭式通风、高压通风机通风等，并就通风研究的发展方向提出了几点建议     

防辐射有机玻璃板材的抗辐射性能

系统研究了含铅有机玻璃、含钡有机玻璃、含硼有机玻璃和普通有机玻璃的ｘ、γ射线和中子射线防护性能及其耐６０Ｃγ射线辐照稳定性。结果表明，含铅有机玻璃板材具有良好的ｘ射线、反应堆热柱γ射线屏蔽性能；合硼有机玻璃板材具有良好的热中子屏蔽性能；含钡有机玻璃板材的褪化裂变谱中子辐射屏蔽性能良好；含钡有机玻璃和普通有机玻璃可耐１０５～１０６Ｇｙ的６０Ｃｏｙ射线辐照；含铅有机玻璃板材耐６０Ｃｏｙ射线照射能力小于１０５Ｇｙ。