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101.
水环境中的邻苯二甲酸酯类污染物及其环境行为研究   总被引:3,自引:0,他引:3  
邻苯二甲酸酯是一类普遍使用的有机化合物质,主要用于聚氯乙烯的增塑剂,目前在水环境中已经大量存在,由于其具有致癌、致畸和致突变性,引起广泛的关注。已有研究表明,邻苯二甲酸酯环境内分泌于扰物,对人类和自然环境有非常大的危害。文章主要对邻苯二甲酸酯类污染物在水环境中的污染现状以及水环境行为的研究现状进行了综述,进入水环境的邻苯二甲酸酯主要是在水体中发生相应的迁移转化,邻苯二甲酸酯能够在水环境中发生生物降解、吸附、水解和光解等环境行为。最后对邻苯二甲酸酯类污染物今后的研究方向进行了展望。  相似文献   
102.
流变相法制备包覆型CMC-Fe0及降解水中TCE的研究   总被引:1,自引:0,他引:1  
樊文井  成岳  余淑贞  范小丰 《环境科学》2015,36(6):2161-2167
以廉价环保的羧甲基纤维素钠(CMC)为表面修饰剂,采用流变相反应法制备包覆型纳米零价铁(CMC-Fe0),用XRD、SEM和TEM、氮气吸附-脱附手段对样品进行表征,并利用合成的零价铁粒子对三氯乙烯(TCE)进行还原脱氯反应.结果表明,当CMC-Fe0投加量为6 g·L-1,TCE初始浓度为5 mg·L-1时,反应40 h去除率达100%.包覆型CMC-Fe0对TCE的还原反应符合准一级反应动力学.最后,对反应产物进行了简单易行的回收.  相似文献   
103.
本文首次从岩石组合、橄榄石与辉石组构、宏观流变、微观流变及波速和各向异性特征等方面详细阐述了东巧地区地幔岩塑性流变学特征,从微观与宏观角度进一步探讨了班公错—怒江结合带东巧地幔岩形成的地质环境及构造演化过程,认为东巧地幔岩具有超高压成因特点,形成于小洋盆环境,在印度板块向欧亚板块推移过程中就位,最终在喜马拉雅整体隆升阶段完成了近地表的构造调整。  相似文献   
104.
According to mate choice models, a female should prefer males with traits that are reliable indicators of genetic quality which the sire can pass on to their progeny. However, good genes may depend on the social environment, and female choice for good genes should be context dependent. The side-blotched lizard, Uta stansburiana, exhibits genetically based throat colors (orange, blue, or yellow) that could be used as a sexually selected signal since they reliably predict the genetic quality of mates. The frequencies of male and female morphs cycle between years, and both male and female morphs have an advantage when rare; thus genetic quality will depend on morph frequency. A female should choose a sire that maximizes the reproductive success of both male and female progeny. We examine a game theoretical model that predicts female mate choice as a function of morph frequency and population density. The model predicts the following flexible mate choice rule: both female morphs should prefer rare males in ’boom years’ of the female cycle (e.g., ’rarest-of-N rule’), but prefer orange males in ’crash years’ of the female cycle (’orange-male rule’). Cues from the current social environment should be used by females to choose a mate that maximizes the future reproductive success of progeny, given the social environment of the next generation. We predict that the cue is the density of aggressive orange females. In the side-blotched lizard, cycling mate choice games and context-dependent mate choice are predicted to maintain genetic variation in the presence of choice for good genes. Received: 8 March 2000 / Revised: 26 August 2000 / Accepted: 4 September 2000  相似文献   
105.
以顾桥煤矿坚硬顶板综采工作面工程地质条件为背景,运用理论分析、数值模拟和现场实测手段,分析了开采速度对工作面覆岩运动、围岩破坏、应力分布和液压支架承载特性的影响。研究结果表明:1个周期来压内工作面落煤引起的岩梁刚性回转下沉量是一定的,工作面作业循环时间引起的岩梁蠕变下沉量与岩梁刚性回转下沉量呈正比,加快工作面推进速度仅减少围岩体蠕变引起的岩梁下沉部分。工作面开采速度增加,覆岩塑性区发育范围减小,煤壁应力集中位置变浅、应力集中系数变小。工作面快速推进时,液压支架承载多为2次増阻和3次増阻,支架工作阻力较小;缓慢推进时,液压支架承载多为1次急增阻,载荷近似呈线性增长,支架工作阻力较大。  相似文献   
106.
107.
随着纳米技术迅猛发展,纳米颗粒的环境行为和生态效应越来越受到关注.纳米氧化物作为环境中的重要组成,广泛存在于水体、大气、土壤以及沉积物中,其大比表面积和高表面活性,控制和影响着环境中一些污染物和营养元素的形态、迁移、转化和生物有效性.纳米尺寸是纳米颗粒特有属性,颗粒尺寸大小调控和决定纳米氧化物的结构及物理化学特性,从而在较大程度上影响其与相关元素的界面反应性和环境地球化学行为.综述了纳米氧化物的尺寸对吸附、(还原)溶解、(催化)氧化、聚集和迁移等环境行为的影响,讨论了尺寸效应的作用机制,最后展望了环境中纳米金属氧化物尺寸效应有关的研究热点和方向.  相似文献   
108.
The present study examined the consequences of a dispersion‐based conceptualization of unit‐level abusive supervision or abusive supervision variability. Abusive supervision variability was proposed to negatively affect a number of employee attitudes and behaviors through the mediating effects of interpersonal justice climate strength. The results revealed significant cross‐level effects such that abusive supervision variability was negatively related to individual perceptions of leader ethicality, organizational ethicality, leader satisfaction, and affective organizational commitment. These effects remained robust after controlling for individual‐level abusive supervision. Abusive supervision variability was also positively related to the frequency with which unit members as a whole engaged in counterproductive work behaviors. Last, the results revealed partial support for the mediating effects of interpersonal justice climate strength. In sum, the findings highlight the importance of examining abusive supervision at both the individual and unit levels of analyses. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
109.
Images of animals, particularly polar bears, harmed by climate change are often used in environmental campaigns, despite warnings of potential reactance and resultant perceived distance from the issue. As an alternative to these emotional appeals, environmental campaigns could encourage an objective (i.e., emotionally detached) perspective on climate change impacts. The present research tests the effects of a message that encourage empathic vs. objective perspectives toward polar bears harmed by climate change on emotions and subsequent support for climate change activism among 241 American adults through an online survey. Contrary to popular warnings, the present research found no reactance toward portraying harm to polar bears from climate change and no benefits of taking an objective perspective toward the polar bears. Instead, portrayals of polar bears harmed by climate change motivated both environmentalists and non-environmentalists to donate money to environmental activist groups when they took an empathic perspective toward the animals. Empathy and hope explain effects for environmentalists and empathy, hope, worry, personal guilt, and boredom explain effects for non-environmentalists.  相似文献   
110.
Pro-environmental behaviors are an important avenue for mitigating environmental impacts. Technological improvements are also a vital tool for reducing environmental damage from consumption. However, their benefits are partially offset by the direct rebound effect, whereby a consumer rationally responds to an increase in resource use efficiency by consuming more. This paper investigates whether technological improvement might also reduce behaviorally motivated mitigation of environmental damage. A behavioral rebound effect operates through two channels. First, pro-environmental effort is reduced after a decrease in marginal environmental damage. Second, moral licensing reduces pro-environmental effort further when technological change is endogenous. I develop a novel real effort laboratory experiment to identify these behaviors. I find a positive behavioral rebound effect. I also find evidence consistent with moral licensing, which is strongest among subjects with a higher degree of pro-environmental attitudes and beliefs. Subjects’ baseline level of pro-environmental effort is driven by beliefs about social norms.  相似文献   
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