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941.
气体检测器及其在环境污染事故应急监测中的应用   总被引:6,自引:0,他引:6  
介绍了常用挥发性有机污染物(VOC)检测器的特性,并阐述了光离子化检测器(PID)的原理,特点及其在环境污染事故应急监测中的应用。  相似文献   
942.
本文通过对河西走廊人口和耕地面积的重建和经济史相关研究成果,利用人类活动对环境影响公式I=PAT,定量重建了河西走廊地区历史时期人类活动对环境影响强度。重建结果显示,可将近2000年以来河西走廊地区的人类活动划分为三个主要阶段,即清代中期以前、清代中期至民国、新中国成立以来。标准化后的环境影响值2千年来平均为6.20,清代中期以前平均为2.79,清代中期以来达到22.50,而近50年来为69.70。  相似文献   
943.
Introduction: Crashes involving roadway objects and animals can cause severe injuries and property damages and are a major concern for the traveling public, state transportation agencies, and the automotive industry. This project involved an in-depth investigation of such crashes based on the second Strategic Highway Research Program (SHRP 2) Naturalistic Driving Study (NDS) data including detailed information and videos about 2,689 events. Methods: The research team conducted a variety of logistic regression analyses, complemented by Support Vector Machine (SVM) analyses and detailed case studies. Results: The logistic regression results indicated that driver behavior/errors, involvement of secondary tasks, roadway characteristics, lighting condition, and pavement surface condition are among the factors that contributed significantly to the occurrence and/or increased severity outcomes of crashes involving roadway objects and animals. Among these factors, improper turning movements (odds ratio = 88), avoiding animal or other vehicle (odds ratio = 38), and reaching/moving object in vehicle (odds ratio = 29) particularly increased the odds of crash occurrence. Factors such as open country roadways, sign/signal violation, unfamiliar with roadway, fatigue/drowsiness, and speeding significantly increased the severity outcomes when such crashes occurred. The sensitivity analysis of the three SVM classifiers confirmed that driver behavior/errors, critical speed, struck object type, and reaction time were major factors affecting the occurrence and severity outcomes of events involving roadway objects and animals. Practical Applications: The study provides insights on risk factors influencing safety events involving roadway objects, including their occurrence and the severity outcomes. The findings allow researchers and traffic engineers to better understand the causes of such crashes and therefore develop more effective roadway- and vehicle- based countermeasures.  相似文献   
944.
为研究高海拔矿井风机气动噪声规律,建立小型轴流风机三维物理模型,利用CFD软件对环境气压分别为1,0.9,0.8,0.7,0.6及0.5 atm时的风机模型进行定常模拟、非定常模拟及噪声计算,并通过自主设计的压变实验装置对上述不同环境气压条件下风机转数分别为500,1 000,1 500和2 000 rpm时的风机噪声进行测试,分析风机叶片附近监测点噪声频谱曲线及压变环境风机噪声实验数据,结果表明:风机转数和环境气压是影响风机气动噪声的2个重要因素;环境气压P一定时,风机转数n越大,各频率下的风机气动噪声声压级SPL越大,且风机噪声总声压级Lp和平均声压级Lavg均随风机转数n的增大呈对数函数增加;风机转数n不变时,随着海拔高度的升高,环境气压P降低,各频段下风机气动噪声声压级SPL均将减小,且风机噪声总声压级Lp和平均声压级Lavg随环境气压值P的降低呈线性函数减小,环境气压每降低0.1 atm,二者分别降低1.47和1.29 dB。  相似文献   
945.
孙朔 《环境与发展》2020,(2):143-144
随着我国对于环境保护工作越来越重视,社会公众也越来越关注企业造成的环境污染问题,企业与政府有关部门的环境执法矛盾逐渐凸显出来。与政府有关部门的工作人员数量相比,存在废水、废气、固废排放现象的企业数量是庞大的,仅靠政府的环境执法明显力量不足,不能有效提高环境污染治理和资源保护的效果。企业自行监测是企业自觉遵守环境相关法律的重要行为,自行监测所得的信息也是政府环境执法的重要基础,本文从企业自行监测入手,分析企业自行监测工作存在的主要问题,探讨企业自行监测信息在环境执法中的应用方式和问题的主要对策,希望可以推动企业在环境执法中的参与度。  相似文献   
946.
陈颖  黄昌付 《环境与发展》2020,(4):162-162,165
大气污染作为环境污染的关键部分,一直困扰着人们的生活,而传统监测设备由于技术具有一定的滞后性,无法满足当前环境监测的需要。而网格化监测有着传统监测设备不具备的优势,在大气污染防治方面发挥着重要的作用,为环境污染治理提供重要的数据保障。基于此,本文主要对大气污染防治网格化监测含义及优势进行了总结概括,并重点对网格化监测的应用展开分析。  相似文献   
947.
以长株潭城市群公共安全规划为研究对象,本着"资源节约、环境友好"两型社会建设的要求,从保护人的安全出发,以实现城乡统筹的风险控制和风险减缓设施建设。长株潭城乡公共安全,规划包括:重大危险源安全规划编制、开敞空间及综合避灾场地规划以及区域综合防灾规划3个方面,强调对城乡统筹的安全内容;该安全规划既是政治经济发展的战略要求,也是政府职能部门的管理要害,还是城乡居民基本的生存保障,具有前瞻性,以完善技术设计来降低风险,同时在管理上加强协调性和拓展性。  相似文献   
948.
为防止气矿开采及运行发生天然气泄漏事故对社会公众造成影响,确保突发情况下快速有序有效地将受到影响的社会公众转移或疏散至安全地带,最大限度保护群众的安全,通过对山区井场周边人群疏散的现场实验,获取山区环境下人群疏散的行为特征、疏散时间、运动速度等数据,为山区地形条件下大规模人群疏散模拟计算提供基础性实验数据,并为井喷事故发生时人员应急疏散组织和管理提供参考。本文及后续文章将报道气矿井场周边人群疏散演练的实验研究。这里,主要对实验方案包括疏散人群、疏散路径及测试方案等进行介绍。  相似文献   
949.
Determinants of outdoor, indoor and personal concentrations of nitrogen dioxide (NO2) were assessed in a subset of pregnant women of the Spanish INMA (Environment and Childhood) Study. Home indoor and outdoor NO2 concentrations were measured during 48 h with passive samplers for 50 and 58 women from the INMA cohorts of Valencia and Sabadell, respectively. Women from Sabadell also carried personal NO2 samplers during the same period. Data on time–activity patterns, socio-economic characteristics, and environmental exposures were obtained through questionnaires. Multiple linear regression models were developed to predict NO2 levels.In Valencia, median outdoor NO2 levels (42 µg/m3) were higher than median indoor levels (36 µg/m3). In Sabadell, personal NO2 showed the highest median levels (40 µg/m3), followed by indoor (32 µg/m3) and outdoor (29 µg/m3) levels. Personal exposure to NO2 correlated best with the indoor NO2 levels. Temporal and traffic-related variables were significant predictors for outdoor NO2 levels. Thirty-two percent of the indoor NO2 variability in the two cohorts was explained by outdoor NO2 levels and the use of the gas appliances. The model for personal exposure accounted for 59% of the variance in NO2 levels in Sabadell with four predictor variables (outdoor and indoor NO2 levels, time spent in outdoor environments and time exposed to a gas cooker). No significant association was found between personal or indoor NO2 levels and exposure to environmental tobacco smoke (ETS) at home.Personal NO2 levels were found to be strongly influenced by indoor NO2 concentrations. The study supports the use of time–activity patterns along with indoor measurements to predict personal exposure to traffic-related air pollution.  相似文献   
950.
Strategic environmental assessment (SEA) in China has developed rapidly since it was introduced into China in the 1990s. Chinese government promulgated the Environmental Impact Assessment Law of China (hereinafter referred to as the EIA Law) in 2002. In this law, it is stipulated clearly that regional and sector plans should be assessed. Through investigating materials and analyzing literatures, this article analyses the practical and academic study achievements of SEA in China that have been achieved since the EIA Law was implemented, probes into the current situation of the main level of SEA in China-plan EIA, then summarizes the development characteristics, and eventually, puts forward the development trends of SEA in China. The research conclusions can offer the foundations for comprehending systematically the progress of SEA in China.  相似文献   
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