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951.
钒是一种重要的生命冗索,同时也是环境污染物之一,因此环境样品及生命有机体中微量钒的测定具有重要的实际意义,是预测和评估其对人体健康、环境发全影响的重要前提之一。环境中钒主要以Ⅳ价和V价存在,因而对钒的测定方法研究主要集中在Ⅳ和Ⅴ价化合物的分离分析上,对Ⅴ(Ⅴ)和Ⅴ(Ⅳ)的分离方法,和光谱法、催化动力法、极谱法、酶学反应法等测定Ⅴ(Ⅴ)、Ⅴ(Ⅳ)和Ⅴ的方法进行了综述。  相似文献   
952.
冯强  胡聃  段宝玲  韩晓丽  边俊 《生态环境》2010,26(6):1312-1317
选取北京城区与郊区典型样点,针对栽植多年的大叶黄杨(Euonymus japonicus)和小叶黄杨(Buxus sinica subsp.sinica var.parvifolia)成龄植株,分别于春、夏、秋3季取样测定叶片的各项生理生化指标,研究了城区与郊区环境下2种灌木的生理生化特性的差异。结果表明:生长前期(春季)城区车公庄2种灌木的叶绿素总量高于郊区植物园,经过一段时期之后低于植物园(夏秋)。Chlb的城郊变化幅度大于Chla。Chla的变化趋势与Chlb相反造成了Chla/b的大幅度变化。大叶黄杨的叶绿素总量和Chla/b比小叶黄杨受城区环境影响更大。城区环境下2种灌木自由水/束缚水降低,脯氨酸质量分数、丙二醛质量摩尔浓度升高,说明城区环境下2种灌木生理代谢水平降低,膜脂过氧化。城区环境下大叶黄杨的自由水/束缚水、脯氨酸质量分数的变化率较小叶黄杨高,2种灌木丙二醛的变化率相近。综合来看,城区环境下大叶黄杨的生理生化反应比小叶黄杨更敏感。  相似文献   
953.
环境基准研究与环境标准制定进展及展望   总被引:4,自引:0,他引:4  
环境基准是一个非常棘手且具有挑战性的科学难题,环境标准制定与修订是一项长期的、艰巨的任务。根据国际上该方向近年来的发展,对环境基准和环境标准的概念与内涵进行了论述,对过去的认识进行了纠正,指出:环境基准不等于环境质量基准,环境基准应该包括环境质量基准和污染环境修复基准2个方面;相应地,环境标准则应包括环境质量标准和污染环境修复标准2个部分。在此基础上,概述了国际和国内有关环境质量基准研究方面取得的显著成绩,列举了法国(作为西欧的代表)、加拿大(作为美洲的代表)和意大利(作为中欧的代表)在环境质量标准制定过程中的先进做法,介绍了美国、英国和俄罗斯等国家在污染环境修复基准研究与污染环境修复标准制定等方面的进展。最后,对我国今后环境基准的研究进行了展望。  相似文献   
954.
A visual-visual dual computer task was designed to test the effect of the thermal environment on dual task performance. The temperatures selected for testing were 20 and 35 °C Wet Bulb Globe Temperature (WBGT). 34 volunteers were randomly assigned to 1 of the 2 temperature conditions. Individual differences in single task performance were controlled by equating the baselines of single task performance. Once individual differences in single task capacity were controlled, statistically significant differences in performance were demonstrated. Mean accuracy was computed over a 1-hr testing period in each temperature condition. Participants’ mean accuracy in the 35° condition (38.18%) was substantially lower than in the 20° condition (50.88%).  相似文献   
955.
本文对信息获取过程中的信息来源分析方法、信息采集方法、信息检索方法、信息加工方法进行了简要介绍,并将上述信息获取方法用于宏观环境督察信息获取过程中,研究了宏观环境督察信息获取机制,并对宏观环境督察信息获取过程进行了详细地分析,为后续的宏观环境督察信息发布提供了基础。  相似文献   
956.
我国室内环境治理的发展状况及趋势   总被引:1,自引:0,他引:1  
综述了我国室内环境治理行业的发展状况;分析了“十二五”期间,我国室内环境治理行业面临的机遇与问题;重点阐述了室内环境治理行业的发展趋势及目标。  相似文献   
957.
This paper reflects on two controversial resource projects – the Bellanaboy gas refinery (Ireland) and the Barvas Moor wind farm (Scotland) – and critical arguments made by key local actors. Although risk, health, environment and development dominated the official decision-making processes, these actors articulated views which cut across or existed beyond such orthodox ideas and framings. Focusing on these, I show that the Gaelic concepts of dùthchas and deoraíocht, summarised as place and exile, help to explain why some residents decided to protest. This paper illustrates the role that history, culture and language can play in conflicts, emphasises the need for greater sensitivity to these and suggests that place and exile can inform alternative visions of sustainability.  相似文献   
958.
This paper explores how residents of Overtown, a low-income neighbourhood in Miami, Florida, view the positive and negative aspects of their neighbourhood “invironment” through photographs taken by residents. The “invironment” [Bell, M., 2004. An invitation to environmental sociology. Thousand Oaks, CA: Pine Forge Press] alludes to the interactions between environment/surroundings and the human body. Residents involved with a community social justice organisation were provided with a photographic workshop and cameras to visually document the positive and negative aspects of their neighbourhood. These participant photographers provided narratives paired with their photographs which were then exhibited at local community events. During the exhibits, community members’ comments on the photographs were recorded. This paper analyses community issues through both photographs and neighbourhood comments inspired by the photographs. The following themes of importance to residents were derived from the photographs and discussion with residents: Housing, Public Space, Neighbourhood Economy, History, Environmental/Invironmental Issues, Human Capital and Power. These themes were all connected by residents’ concerns about inequality in Overtown compared to other neighbourhoods in Miami.  相似文献   
959.
Little is known about the legislative process and in particular how this relates to environment in Latin America. This article attemps to partially close this gap by discussing the dynamics of congressional environmental politics in Chile under former President Lagos (2000–2006). At first, this article discusses the role of the executive branch in the legislative process, congressional authority and environmental policy. This sometimes uneasy relationship is explored, and its consequences over environmental politics are discussed. The second part of the article attempts to explain legislator's choices in the area of environmental policy, developing and testing four main hypotheses that eventually help to explain why legislators support/reject laws of positive/negative environmental relevance. Finally, this article draws general conclusions on Chilean congressional politics and environmental policy, to then propose some recommendations on how to improve the process of creating environmental policy in Congress.  相似文献   
960.
Boston's Chinatown is an urban community surrounded by businesses, a university, a large medical centre, and an area zoned for “adult entertainment” called the Combat Zone. The overall goal of this exploratory study was to examine the temporal and geographic distribution of street crime in Boston's Chinatown using police crime reports from the years 1988 to 2004. Crime patterns were most notably associated with the presence of the adult entertainment area, known as the Combat Zone. However, despite the decline of adult businesses over the study period, we saw small limited reduction in property and violent crimes, suggesting that the decline of these businesses did not lead to large-scale short-term (<5 years) reductions in crime.  相似文献   
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