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991.
高含硫天然气净化厂工程的运营将不可避免地引起一系列的生态环境负效应.本文在借鉴国内外生态评价相关研究成果的基础上,提出了高含硫天然气净化厂工程运营期生态环境负效应评价指标体系,并采用德尔菲法与层次分析法确定了各指标的权重.经用于川渝地区某高含硫天然气净化厂实例研究,通过模糊综合评价法得出该净化厂运营初期产生的环境负效应为Ⅲ级(中等)的结论,这与工程影响区实际调查结果较为一致,表明文中建立的评价指标体系和采用的评价方法较合理,可为类似净化厂工程生态环境负效应研究与评价提供实用参考.  相似文献   
992.
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   
993.
Three cruises were carried out in Jiaozhou Bay (JZB) in the neap tide in October 2002 (fall) and in both neap and spring tides in May 2003 (spring) to understand the relative importance of external nutrient inputs versus physical transport and internal biogeochemical processes. Nutrients (, , , , silicic acid, total dissolved nitrogen (TDN) and phosphorus (TDP), dissolved organic nitrogen (DON) and phosphorus (DOP)) were measured. The concentrations of nutrients were higher in the northern part than in the southern part. High concentrations of and DON in JZB demonstrated the anthropogenic input. Ambient nutrient ratios indicated that the potential limiting nutrients for phytoplankton growth were silicon, and then phosphorus. Nutrients showed an obvious tidal effect with low values at flood tide and high values at ebb tide. Nutrient elements were transported into JZB in the north and output in the south (i.e., into the Yellow Sea), which varied with season, tidal cycle and investigation sites. Water exchange between JZB and the Yellow Sea exports , and DON out of JZB, while it inputs , silicic acid and DOP into JZB. Nutrient budgets demonstrate that riverine input and wastewater discharge are major sources of nutrients, while residual flow is of minor importance in JZB ecosystem. JZB is a sink for the nutrient elements we studied except for DON. Stoichiometric calculations demonstrate that JZB is a net autotrophic system.  相似文献   
994.
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   
995.
稀土离子对超氧阴离子自由基生成的抑制作用   总被引:9,自引:0,他引:9  
庞欣  王东红  彭安 《环境化学》2001,20(6):557-560
利用肾上腺素在碱性条件下自氧化产生超氧阴离子自由基(O^.-2)的性质,研究了稀土硝酸盐对生成O^.-2的抑制作用。稀土硝酸盐与超氧化物歧化酶(SOD)具有相似的性质,对肾上腺素自氧化生成的O^.-2有明显的抑制作用。抑制率在16.3%-78.4%之间,而且体系中稀土硝酸盐的浓度与其对O^.-2的抑制率之间有明显的剂量效应关系。  相似文献   
996.
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   
997.
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   
998.
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   
999.
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   
1000.
以互花米草幼苗为受体植物,选用无瓣海桑凋落叶、根、果的5个质量浓度梯度(0.1、0.2、0.3、0.4、0.5 g/mL)水浸液为处理液,研究无瓣海桑对互花米草幼苗的化感效应。结果表明:不同浓度的无瓣海桑凋落叶、根和果的水浸液对互花米草幼苗具有不同程度的化感作用,且存在"高抑低促"的浓度效应。所有水浸液均表现出高浓度下(高于0.3 g/mL)明显抑制互花米草的生长,随着浓度降低其抑制作用逐渐减弱,甚至转为轻微促进作用(即0.1 g/mL时)的规律。无瓣海桑不同器官的水浸液对互花米草幼苗生长的综合化感抑制强度为:果>根>凋落叶。  相似文献   
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