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991.
Disinfection of water for human use is essential to protect against microbial disease; however, disinfection also leads to formation of disinfection by-products (DBPs), some of which are of health concern. From a chemical perspective, swimming pools are a complex matrix, with continual addition of a wide range of natural and anthropogenic chemicals via filling waters, disinfectant addition, pharmaceuticals and personal care products and human body excretions. Natural organic matter, trace amounts of DBPs and chlorine or chloramines may be introduced by the filling water, which is commonly disinfected distributed drinking water. Chlorine and/or bromine is continually introduced via the addition of chemical disinfectants to the pool. Human body excretions (sweat, urine and saliva) and pharmaceuticals and personal care products (sunscreens, cosmetics, hair products and lotions) are introduced by swimmers. High addition of disinfectant leads to a high formation of DBPs from reaction of some of the chemicals with the disinfectant. Swimming pool air is also of concern as volatile DBPs partition into the air above the pool. The presence of bromine leads to the formation of a wide range of bromo- and bromo/chloro-DBPs, and Br-DBPs are more toxic than their chlorinated analogues. This is particularly important for seawater-filled pools or pools using a bromine-based disinfectant. This review summarises chemical contaminants and DBPs in swimming pool waters, as well as in the air above pools. Factors that have been found to affect DBP formation in pools are discussed. The impact of the swimming pool environment on human health is reviewed.  相似文献   
992.
征税,还是补贴--对当前环境经济政策的反思   总被引:10,自引:0,他引:10  
现行环境经济政策的目标在于纠正经济主体的外部不经济性,具体是通过税收或产权交易使外部成本内部化,本文称其为环境经济政策的“不对称性”。因为外部效应除了外部不经济以外,还有外部经济,现行的环境经济政策只考虑了前者却完全忽视了后者,只强调了外部成本的内部化却忽视了外部收益也应该内部化。以此为出发点,文章从现行政策的对立面出发,探讨了围绕外部收益内部化制定环境经济政策的必要性和可行性。最后作者分析了目前排污权交易存在的严重问题,并给出了解决问题的方法。  相似文献   
993.
China is experiencing a process of rapid industrialization and urbanization at the cost of agricultural land and environment,particularly in the costal areas. This study takes Jinan as a case presenting a time-series analysis of urban land expansion from 313 to 2003. The results show that the urban expansion of Jinan city mainly took place in the last 100 years, especially after the economic reform in 1978. Social development and economic growth,urban population growth and migration policies were factors driving the urban land expansion. Urban sprawl resulted in a disappearance of wetlands and a great loss of agricultural land, and over-pumping of ground water that led to disappearance of the city‘s feature,namely “the city of springs“.  相似文献   
994.
选取沪深两市2011年-2014年化学原料和化学制品制造业88家上市公司为研究样本,采用实证分析方法研究两者之间的关系.环境绩效用单位营业收入排污费来衡量,财务绩效用总资产净利率来衡量.考虑到财务绩效的影响因素不仅有环境绩效,所以加入了公司规模等控制变量.分析结果显示,环境绩效与财务绩效并不是相互矛盾的关系,环境绩效的改善可以帮助公司获得更多的经济利润,企业可以在生产经营的同时主动地去履行环境保护的责任,实现环境与经济绩效的共赢.  相似文献   
995.
IntroductionIn an aging society that is more and more information-oriented, being able to replace human passengers’ protective effects on vehicle drivers with those of social robots is both essential and promising. However, the effects of a social robot’s presence on drivers have not yet been fully explored. Thus, using a driving simulator and a conversation robot, this experimental study had two main goals: (a) to find out whether social robots’ anthropomorphic qualities (i.e., not the practical information the robot provides drivers) have protective effects by promoting attentive driving and alleviating crash risks; and (b) by what psychological processes such effects emerge. Method: Participants were recruited from young (n = 38), the middle-aged (n = 39), and the elderly (n = 49) age groups. They were assigned to either the treatment group (simulated driving in a conversation robot’s presence) or the control group (simulated driving alone), and their driving performance was measured. Mental states (peaceful, concentrating, and reflective) also were assessed in a post-driving questionnaire using our original scales. Results: Although the group of older participants did not experience protective effects (perhaps due to motion sickness), the young participants drove attentively, with the robot enhancing peace of mind. The protective effect was also observed among the middle-aged participants, and the verbal data analysis ascribed this to the robot’s role of expressing sympathy, especially when the middle-aged drivers nearly had not-at-fault crashes, which caused them to be stressed. In conclusion, we discuss the practical implications of the results.  相似文献   
996.
王丽芬  邓辅唐  孙珮石  卿小燕 《环境工程》2012,(Z2):396-399,457
以白菜为试材,研究了水葫芦渣有机肥在高量、中量、低量3个施用水平下的施用效果。结果表明,水葫芦渣有机肥对白菜的生长发育具有明显的促进作用,从株高的指标看,以施有机肥高量效果为佳;从最大功能叶面积指标看,以施有机肥高量效果为佳;从开展度指标看,以施有机肥中量效果为佳。从白菜产量上看,有机肥化肥配施低用量、有机肥高用量、中用量差异不显著,均比空白增产370%、364%、297%。从白菜对养分吸收的含量上看,全氮以施有机肥高用量最好;全钾以施有机肥低用量最好。将水葫芦渣有机肥与其它常见的有机肥比较,其肥效与其它有机肥相当。  相似文献   
997.
分析了航天器环境工程研发项目档案管理的现状及存在的问题,阐述了档案管理对航天器环境工程研发工作的作用和意义。总结了对国家重点基础研究项目"空间环境下卫星长寿命评估、验证与保障技术研究"档案的管理情况,并对我国航天器环境工程研发项目档案管理工作提出了建议。  相似文献   
998.
Introduction: Safety is a critical factor in promoting sustainable urban non-motorized travel modes like bicycles. Helmets have shown to be effective in reducing injury severity in bicycle crashes, however, their effects on bicyclists’ behaviors still requires deeper understanding, especially amid the emerging trend of using shared bicycles. Risk compensation effects suggest that bicyclists may offset perceived gains in safety from wearing a helmet by increasing risk-taking behaviors. A better understanding of these compensation effects can be useful in assessing various bicycle safety related programs. Method: Using a sample of 131 bicyclists from the San Francisco Bay area, this research studies how bicyclists respond with respect to risk-taking behaviors under various urban-street conditions, as a function of helmet use. Study participants were each shown 12 videos, shot in Berkeley, California, from the perspective of a bicyclist riding behind another bicyclist. A fractional factorial experiment design was used to systematically vary contextual attributes (e.g., speed, bike lane facilities, on-street parking, passing vehicles) across the videos. After each video, participants were asked to indicate if they would overtake the bicyclist in the video. With the help of data adaptive estimation techniques, targeted maximum likelihood estimation (TMLE) was applied to estimate the average risk difference between helmeted users and non-users, controlling for self-selection effects. Individual-based nonparametric bootstrap was performed to assess the uncertainty associated with the estimator. Results: Our findings suggest, on average, individuals more likely to wear a helmet are 15.6% more likely to undertake a risky overtaking maneuver. Practical Applications: This study doesn’t try to oppose mandatory helmet laws, but rather serves as a cautionary warning that road safety programs may need to consider strategies in which unintended impact of bicycle helmet use can be mitigated. Moreover, our findings also provide additional evaluation component when it comes to the cost-benefit assessment of helmet-related laws.  相似文献   
999.
Standardized test protocols are used in the regulatory context for identifying the hazardous properties of chemicals, wastes, and contaminated materials. This paper compares the relevance of two guidelines measuring effects on terrestrial plants, the OECD TG 208 and the ISO TG 22030 and presents the scientific basis for a recent decision of the European Chemicals Agency (ECHA) under the European chemicals regulation REACH. If there are no specific phytotoxicity alerts, both guidelines are considered suitable for assessing long-term hazards, providing that a sufficient number of species is included in the OECD protocol, the recommended minimum number is six, which offer a reasonably broad selection of species to account for interspecies sensitivity. The proposed methodology, based on a combination of probabilistic assessments using Monte Carlo analysis, can be adapted for supporting similar decisions under specific regulatory processes; for example, for assessing contaminated soils or pesticides’ applications.  相似文献   
1000.
Abstract:  Despite the growing concern over reptile population declines, the effects of modern industrial silviculture on reptiles have been understudied, particularly for diminutive and often overlooked species such as small-bodied snakes. We created 4 replicated forest-management landscapes to determine the response of small snakes to forest harvesting in the Coastal Plain of the southeastern United States. We divided the replicated landscapes into 4 treatments that represented a range of disturbed habitats: clearcut with coarse woody debris removed; clearcut with coarse woody debris retained; thinned pine stand; and control (unharvested second-growth planted pines). Canopy cover and ground litter were significantly reduced in clearcuts, intermediate in thinned forests, and highest in unharvested controls. Bare soil, maximum air temperatures, and understory vegetation all increased with increasing habitat disturbance. Concomitantly, we observed significantly reduced relative abundance of all 6 study species (scarletsnake [Cemophora coccinea] , ring-neck snake [Diadophis punctatus] , scarlet kingsnake [Lampropeltis triangulum] , red-bellied snake [Storeria occipitomaculata] , southeastern crowned snake [Tantilla coronata] , and smooth earthsnake [Virginia valeriae] ) in clearcuts compared with unharvested or thinned pine stands. In contrast, the greatest relative snake abundance occurred in thinned forest stands. Our results demonstrate that at least one form of forest harvesting is compatible with maintaining snake populations. Our results also highlight the importance of open-canopy structure and ground litter to small snakes in southeastern forests and the negative consequences of forest clearcutting for small snakes.  相似文献   
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