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排序方式: 共有1291条查询结果,搜索用时 203 毫秒
991.
根据珠江三角洲地区16个典型站点2006年监测的PM10浓度数据,以珠江三角洲地区人群2006年PM10暴露浓度作为基准,采用泊松回归模型和寿命表方法,评价PM10浓度对人群健康影响.该区2006年PM10年均浓度达到73μg/m3,若所有监测城市PM10浓度达到国家二级标准(100μg/m3),成人(≥30岁)可避免死亡人数为2300人,人群平均期望寿命延长0.13a.当PM10年均浓度达到WHO推荐过渡指标值(70,50,30μg/m3)及指导值(20μg/m3)后,成人可避免死亡人数分别为8700,19700,32600,38500人;人群平均期望寿命分别延长0.47,1.1,1.9,2.3a.  相似文献   
992.
包气带土层中石油污染物生物降解的温度效应   总被引:7,自引:2,他引:7  
张旭  李广贺  黄巍 《环境科学》2001,22(4):108-110
温度是影响包气带土层中石油污染物自然衰减的重要因素.通过室内模拟实验对油污土层微生物降解的温度效应进行研究,并预测不同温度下石油污染物的半衰期.结果表明,温度对生物反应速率常数的影响符合关系式K=3145exp(-5233/T).根据该式对石油污染物的半衰期进行预测,得出5℃、10℃、20℃和30℃时包气带土层中石油污染物的半衰期分别为1499 d、1075 d、572 d和317 d.  相似文献   
993.
Ceyhan E  Ceyhan AA 《Disasters》2007,31(4):516-529
This study investigates the quality of life (QOL) and academic achievement of earthquake survivors six years after the earthquakes in Marmara, Turkey. Data were collected from 407 Turkish university students. Of these, 201 were earthquake survivors and 206 had not been exposed to an earthquake. The Turkish adaptation of the brief version of the World Health Organisation's QOL instrument (WHOQOL-BREF, TR) was used to measure QOL. The results reveal that the earthquake survivors' psychological and environmental domains of QOL and academic achievement were significantly lower than those of individuals not exposed to an earthquake. The results also highlight the risk factors that affect the QOL of the earthquake survivors significantly. These are their gender, their age at the time of earthquake and the continued existence of financial difficulties linked to the earthquakes.  相似文献   
994.
为验证《疫情期间豁免机组成员值勤期、飞行时间限制的实施办法》的可行性,以及为其提供科学依据。以飞行机组成员在驾驶舱内的警觉性变化为验证指标,基于警觉能理论,建立量化评估驾驶舱内飞行机组警觉性的数学模型,以飞行过程中的轮换安排为例进行舱内机组警觉性的数值模拟仿真,并对比分析"CCAR-121部"规章与"豁免办法"中不同飞行时间限制下的舱内机组警觉性预测仿真结果。结果表明:以文中排班和轮换安排的情况下,以"豁免办法"进行运行时,驾驶舱内飞行机组的警觉性整体上不低于"CCAR-121部"规定,因此,"豁免办法"的实施具有可行性和科学性。  相似文献   
995.
为探究和定量分析疲劳驾驶交通事故严重程度的影响因素,以广东省1 370条疲劳驾驶事故数据为基础,对比分析不同年份、时间段以及年龄段的疲劳驾驶交通事故特征;以交通事故严重程度为因变量,将其分为严重事故和非严重事故,从驾驶员年龄、驾龄、车辆类型等17个初步选择的自变量中筛选对疲劳驾驶交通事故严重程度具有显著影响的因素;采用二元Logistic回归模型分别对全体数据和不同道路类型下的数据建立疲劳驾驶交通事故严重程度预测模型,并对模型进行参数估计和检验。研究结果表明:模型拟合度良好,准确性高;对疲劳驾驶交通事故严重程度具有显著影响的因素有年龄、人员类型、车辆类型、道路类型、道路线形和能见度;车辆类型和道路线形是影响城市道路交通事故严重程度的重要因素,能见度是影响1,2级及其他更低级道路交通事故严重程度的重要因素。  相似文献   
996.
美洲斑潜蝇在中国山西的生活史及其主要习性   总被引:4,自引:0,他引:4  
在山西省自然条件下,美洲斑潜蝇一年通常发生9代,个别年份发生8代或10代.深秋至翌年春季,该虫可在当地的日光温室内连续为害,发生约3~4代(11月至下年3月间).通过试验证明,美洲斑潜蝇在35°N以北的地区不能自然越冬,蔬菜储藏室是其越冬的主要场所.本文还对此蝇的主要习性进行了报道.图3表7参14  相似文献   
997.
将时间因素和生物碳通量纳入林产品生命周期碳足迹评估,通过动态生命周期分析法(Dynamic Life Cycle Assessment,DLCA),确定林产品生产、使用和废弃阶段替代化石能源的净温室气体减排和对森林碳损失的净弥补时间。首先,建立温室气体排放和封存的动态生命周期清单,评估刨花板全生命周期的碳动态和碳足迹;其次,根据ISO 14040和PAS 2050标准提供的静态生命周期分析法分别核算包含与不包含碳储计算的碳足迹,量化时间因素和生物碳通量对于碳足迹结果差异的影响程度;最后,对比自然生长状态的森林碳汇情境,评估刨花板使用和废弃阶段替代化石燃料实现净气候减排所需的时间。研究表明:①时间因素和生物碳通量核算对碳足迹结果影响较大(223.34%),忽视时间因素会低估刨花板的减排贡献(18.98%)。②动态生命周期分析法可准确评估生物碳和温室气体排放的时间问题,但对时间范围非常敏感(75.19%和113.25%)。③生产、使用林产品以及林产品对化石能源的替代是实现长期气候减排的有效方式,在100a的时间范围能够弥补因森林砍伐造成的碳损失,从而实现碳中性。  相似文献   
998.
This article studies environmental information as it circulates in social media, specifically in personal blogs and microblogs. It rests on a thematic analysis of a selection of Swedish language, personal, everyday life environment blogs active during 2011 and 2012 and the social media applications connected to these blogs. Gibson's concept of affordances and Foucault's notion of governmentality are brought together to examine how material and technological affordances of social media and the structures of governmentality work together to engender a type of information on environmentally friendly living that is rooted in the conditions of the Web, together with a view of society which is structured around choice and individual responsibility. The article argues that information is woven into the texture of the social on every level, including everyday life practices, and hence social media, as tools in such practices, contribute to shaping the way in which information on environmentally friendly living is articulated, shaped, and filled with meaning.  相似文献   
999.
Abstract

Metolachlor [2‐chloro‐N‐(2‐methoxy‐1‐methylethyl)‐2'‐ethyl‐6'‐methyl acetanilide] dissipation under both field and laboratory conditions were studied during summer season in an Indian soil. Metolachlor was found to have moderate persistence with a half‐life of 27 days in field. The herbicide got leached down to 15–30 cm soil layer and residues were found up to harvest day of the sunflower crop in both 0–15 cm and 15–30 cm soil layers. Metolachlor was found to be more persistent in laboratory studies conducted for 190 days. The rate of degradation was faster in soil under flooded partial anaerobic conditions as compared to aerobic soil with a half‐life of 44.3 days. In aerobic soil, metolachlor was very stable with only 49% dissipation in 130 days. Residues remained in both the soils up to the end of the experimental period of 190 days.  相似文献   
1000.
Frequent business travel can be a burden for travelers' work and private life. We tested whether preventive coping (the proactive accumulation of resources in advance of potential stressors) makes such trips beneficial despite their potential to be stressful. In a longitudinal three‐wave study, we investigated whether frequent travel relates to an increase or decrease in work–life balance, emotional exhaustion, work engagement, and relationship satisfaction depending on preventive coping. Findings from a sample of 133 frequent business travelers revealed significant indirect effects for emotional exhaustion, work engagement, and relationship satisfaction through work–life balance. Among employees who engaged less in preventive coping, a higher number of business trips was related to a decrease in work–life balance, which, in turn, was related to more emotional exhaustion, less work engagement, and lower relationship satisfaction. Among those who reported higher preventive coping, we found opposing indirect effects: Frequent travel was related to an increase in work–life balance and, in turn, to less emotional exhaustion, more work engagement, and higher relationship satisfaction. These findings advance our knowledge in the field of business travel, future‐oriented coping, and work–life balance. They highlight that travelers and their organizations should resort to preventive coping to make frequent travel more beneficial.  相似文献   
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