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121.
Environmental management is moving away from the traditional use of specialists to currect end-of-the-pipe problems and instead is moving back in the process to reduce the production of these waste materials. The author shows how integrating environmental responsiblity all the way down the production line might work in a practical application, including a ten-step formula for putting a total quality environmental program in place.  相似文献   
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INTRODUCTION: The purpose of the study reported here was to develop and pilot test a comprehensive battery of assessment instruments for older drivers that would be inexpensive and easy to administer so that it could be used in longitudinal studies. METHOD: The resulting battery was developed by selecting a set of validated assessment instruments and combining them into a package, with a total acquisition cost of less than $900. As part of this battery, three questionnaires were developed utilizing items from established questionnaires with minor modifications. The battery was pilot tested with a convenience sample of 38 drivers aged 65 years or older. RESULTS: Results showed that the entire battery required less than one hour to complete. Data from the assessment outcomes fell within normative ranges. Feedback from subjects indicated that the battery was acceptable, free of problems, presented tasks in a good order, and was not too long. CONCLUSIONS: Based on study findings, the assessment battery appeared to be low-cost, transportable, easy to administer, easy for subjects to complete, provides a comprehensive assessment of a person's physical health, mental health, and driving behaviors, and would serve as a valuable data collection tool for a longitudinal study of older drivers. Such a longitudinal study is needed in order to answer some of the most important questions about older driver safety and mobility.  相似文献   
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Within national greenhouse gas inventories, many countries now use widely-accepted methodologies to track carbon that continues to be stored in wood products and landfills after its removal from the forest. Beyond simply tracking post-harvest wood carbon, expansion of this pool has further been suggested as a potential climate change mitigation strategy. This paper summarizes data on the fate of carbon through the wood processing chain and on greenhouse gas emissions generated by processing, transport, use and disposal of wood. As a result of wood waste and decomposition, the carbon stored long-term in harvested wood products may be a small proportion of that originally stored in the standing trees—across the United States approximately 1% may remain in products in-use and 13% in landfills at 100 years post-harvest. Related processing and transport emissions may in some cases approach the amount of CO2e stored in long-lived solid wood products. Policies that promote wood product carbon storage as a climate mitigation strategy must assess full life-cycle impacts, address accounting uncertainties, and balance multiple public values derived from forests.  相似文献   
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邻苯二甲酸丁基苄酯致神经细胞氧化损伤   总被引:4,自引:3,他引:1  
为探究邻苯二甲酸丁基苄酯(butyl benzyl phthalate,BBP)对小鼠神经的毒性作用,进行了小鼠体外毒理学研究。首先用不同浓度的邻苯二甲酸丁基苄酯染毒神经模型细胞—N2a神经瘤细胞,通过噻唑蓝比色法(MTT),Hoechst 33258染色实验评价邻苯二甲酸丁基苄酯的细胞毒效应;通过对染毒细胞氧自由基(ROS)、丙二醛(MDA)、还原型谷胱甘肽(GSH)含量的检测来探究BBP对小鼠神经瘤细胞的氧化损伤效应。随着BBP浓度的不断增高,细胞的MTT值逐渐变小,当BBP的浓度达到10 g·L-1时,MTT实验结果与对照组出现显著性差异;Hoechst 33258染色结果显示:高浓度的BBP导致细胞核呈现出不规则状态,出现了凋亡小体;随着BBP染毒浓度的升高N2a细胞中的ROS水平和MDA含量逐渐上升,分别在0.16 g·L-1和10 g·L-1开始与对照组相比出现了显著性的差异(p0.05);而GSH系数呈现下降趋势,在0.32 g·L-1时开始出现显著性差异(p0.05)。实验结果表明高浓度的邻苯二甲酸丁基苄酯可以导致神经瘤细胞的凋亡,并产生氧化损伤效应。  相似文献   
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Reversed phase thin layer chromatography (RPTLC) has been investigated for the estimation of octanol/water partition coefficients (P), an important parameter for the prediction of the environmental behaviour of organic chemicals. A strong correlation between P derived from the traditional octanol/water system and RPTLC has been established over five orders of magnitude. RPTLC data are likewise correlated to results obtained by high performance chromatography (HPLC). Due to the low costs, simplicity and separation power RPTLC is especially suited for the investigation and screening of mixtures of compounds before more complicated tests are involved.

Results from a round robin test on the determination of partition coefficients by HPLC, RPTLC and the batch method indicate the simplicity and accuracy of the RPTLC technique. Applications of the RPTLC‐technique on technical products and industrial waste waters are described.  相似文献   
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Preliminary mineral magnetic results from a pilot project investigating the suitability of roadside tree leaves as depositories of vehicular pollution are presented. Tree leaf surfaces (Lime: Tilia europaea; Sycamore: Acer pseudoplatanus) at four roadside and one woodland location in Wolverhampton, UK, have been monitored (July 2003 to November 2003). Mineral magnetic technologies have revealed spatial variations of particulate pollution concentration throughout the conurbation and data analysis indicates that magnetic concentration parameters are suitable proxies for fine particulate pollution, which are particularly hazardous to health. Site-specific traffic management and associated vehicle behaviour appear to be chiefly responsible for the magnetic concentration differences between sites. Magneto-biomonitoring in this way allows the high-resolution spatial mapping of particulate matter (PM) pollution, which may also benefit epidemiology in better assessing exposure to vehicular-derived particulates. Given the speed, measurement sensitivity and non-destructive nature of the technique, it is proposed that this low-cost approach offers some advantages over centralised monitoring stations to monitor urban roadside particulate pollution.  相似文献   
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