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排序方式: 共有1212条查询结果,搜索用时 312 毫秒
781.
Restoration processes of pollution zones in Hanjiang River   总被引:1,自引:1,他引:1  
RestorationprocessesofpollutionzonesinHanjiangRiver¥ShenYunfen;TanYuyun;FengWeisong;GuManru(InstituteofHydrobiology,ChineseAc...  相似文献   
782.
Fungi exposure has been linked to asthma and allergies among children. To determine the association between fungal exposure and wheeze and rhinitis symptoms, we examined concentrations of culturable indoor and outdoor fungi of various aerodynamic sizes in low and high allergic prevalence child care centers (CCCs) in Singapore. Environmental parameters were also performed for air temperature, relative humidity and ventilation rates, while information on CCC characteristics was collected via an inspection. Most commonly recovered fungi were Penicillium, Aspergillus, Geotrichum, Cladosporium and sterile mycelia with Geotrichum and sterile mycelia amounting to an average of 71.5% of the total airborne culturable fungi studied. Indoor and outdoor total culturable fungi concentrations and those in the size range of 1.1–3.3 μm were significantly higher in high allergic prevalence CCCs. When fungal types/genera were compared, indoor and outdoor Geotrichum and sterile mycelia of aerodynamic sizes 1.1–3.3 μm were found to be significantly elevated in high allergic prevalence CCCs. Indeed, average geometric mean diameters (Dg, ave) of indoor and outdoor culturable fungi were consistently smaller in CCCs with high prevalence of allergies than those with low prevalence. We found significant associations of higher fungal concentrations, especially those with smaller aerodynamic sizes in CCCs situated near parks. There were no differences in fungal levels between CCCs with respect to their dampness profile mainly due to high CCC ventilation rates. Since particle size is a factor that determines where a fungi particle deposits in the respiratory tract, this study provides useful information in the etiology of wheeze and rhinitis symptoms among the CCC attending children.  相似文献   
783.
The study examined the effects of situational (store busyness and customer demand) and dispositional (extraversion, neuroticism, and psychoticism) factors on the display of positive emotions. We found that for situational factors, customer demand was positively related to displayed positive emotions. For personality factors, extraversion was positively related to displayed positive emotions and neuroticism was negatively related to displayed positive emotions. Usefulness analysis showed that both situational and personality factors contributed significantly to explain the level of positive displayed emotion. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
784.
结合河北省桃园农药厂开发的百草枯新工艺(低温钠法),对百草枯生产过程中的环境风险进行评价。首先介绍了百草枯生产的工艺流程,然后系统分析了金属钠、吡啶、氯甲烷以及百草枯等危险物的性质及其危害性,并在上述分析的基础上,采用相应的评价模型对钠化釜及合成釜中吡啶可能造成的爆炸与扩散进行了评价。最后,就百草枯生产的环境风险提出了相应的对策和防范措施。  相似文献   
785.
电化学法消毒处理医院污水的试验研究   总被引:1,自引:0,他引:1  
采用电化学法消毒处理医院污水,通过选用不同阳极材料构建的电化学体系,探讨电化学法的消毒机理。试验表明,以涂有贵金属(钌、铂和铱)氧化物的钛板作阳极,不锈钢板作阴极,在电流密度为8mA/cm^2、水力停留时间为15min、空气流量为40L/h、极水比为1.0的试验条件下,消毒后污水中总大肠菌群数(500cfu/L,达到国家一级排放标准(GB8978-1996)。  相似文献   
786.
采用Fenton法对垃圾渗滤液膜滤浓缩液进行预处理,探讨了pH值、FeSO4/H2O2用量及比例、以及反应时间对CODcr及色度去除率的影响.研究结果表明:当pH =4.0,FeSO4/H2O2用量0.75/7.5 (g/ml),反应时间2.5h,垃圾渗滤液膜滤浓缩液的CODcr浓度从4 416 mg/L降低至630.7 ml/L,CODcr去除率达85.7%;色度从1 250倍降低至200倍以下,色度去除率达84%.因此,本工艺对垃圾渗滤液膜滤浓缩液的CODcr及色度具有较好的去除效果,作为垃圾渗滤液膜滤浓缩液的预处理工艺具有可行性.  相似文献   
787.
The impending form and extent of climate change and its direct impacts present disproportionate challenges for the most socially and economically disadvantaged groups within populations. Evaluating the vulnerability of disadvantaged groups in the context of climate change has presented tremendous theoretical, methodological and policy challenges especially where vulnerability assessment research is focused at the local community level. This study addresses the challenges by developing an interdisciplinary methodology, based on expert knowledge, and uses the state of South Australia as a case study. It focuses on key indicators that measure the exposure of local communities to climate change and socio-economic vulnerabilities of local populations. A main contribution in this study is the novel incorporation of physical, environmental and socio-demographic data sets and extensive use of spatial modelling and estimation methods to spatially define climate change and social vulnerability “hot spots”. This paper assesses vulnerability under moderate and high Intergovernmental Panel on Climate Change CO2 emission scenarios in order to generate an assessment model to be used before planning is done. The result is the creation of a practical tool through which decision-makers can better understand how the complexity of one's local spatial context influences the unique exposure, which different vulnerable communities have, to the impacts of climate change. This paper presents a useful tool that can be used in the initial assessment phase by planners and policy-makers to better assist those who are limited in their ability to adapt to climate change.  相似文献   
788.
环境库兹涅茨曲线(Environmental Kuznets Curve,简称EKC),常用来描述经济增长与环境质量之间的关系,传统的环境库兹涅茨曲线一般具有倒"U"形特征。通过对1990年-2010年台州市环境数据和经济数据的计量模型研究,发现台州市排放的污染物环境库兹涅茨曲线不完全符合传统的环境库兹涅茨曲线特征,并对这一结果进行了深入分析。环境质量的改善并不是随着人均GDP的增长而自动发生。除了经济收入这个因素外,影响环境质量的因素还有很多,如种族构成、公民受教育程度、集体行动的倾向性、人口密度等等。经过研究得出结论:台州市总体环境状况有着进一步恶化的趋势,应该加大环保力度,提倡清洁生产和"三废"循环利用,使经济增长与环境状况同时向着有利于人类的方向发展,实现可持续发展。  相似文献   
789.
随着重金属污染的越来越重,重金属对土壤环境的危害引起人们广泛的关注,土壤酶作为土壤生态系统中生化反应的催化剂,对各种土壤代谢过程起驱动作用.为研究单因素重金属Cu、Cd对于土壤脲酶活性的影响,以至于对环境保护和环境评价工作提供意见.本文采用靛酚蓝比色法测定脲酶活性,以氨氮浓度表征土壤脲酶活性.实验结果表明,随着Cu2+、Cd2+浓度的增加,土壤脲酶活性显著降低,即重金属对土壤脲酶具有抑制作用.  相似文献   
790.
环境影响评价既是技术,也是正确处理环境保护与经济增长关系的重要手段,是强化环境管理的积极措施,可为经济发展和环境保护决策提供参考依据。本文梳理总结了近年来红桥区污染物排放情况、环境影响评价预测污染物排放情况以及环境影响评价消减污染物排放情况,分析了红桥区环境影响评价的执行情况,通过对红桥区实践环境影响评价出现的问题分析,针对性地提出建议。  相似文献   
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