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1.
利用长沙市城区2011年及2012年连续自动监测获得的CO2数据,两年的平均值为412.2×10^-6,高于世界本底站青海瓦里关5.6%,与临安、无锡相当,略高于乌鲁木齐,而低于北京、上海。冬季CO2浓度日小时变化呈现双峰形态,峰值出现在上午9时及晚上19时~21时。夏季日小时变化为单峰形态,峰值出现在上午8时。冬季CO2浓度日均值为420.3×10^-6,比夏季高3.4%。CO2除与O3呈负相关以外,与其它污染物均呈现显著性正相关,特别是与CO、NO、NO2、NOx、SO2的相关性最强,而与颗粒物(PM10、PM25)的相关性稍差。  相似文献   

2.
通过承钢烧结机脱硫出口SO2的比对监测,发现在线及手持监测设备正常但监测数据仍比对不合格。进行CO干扰实验,得出CO对采用"定电位电解法"的手持SO2分析仪有正干扰,并得出了干扰系数。现场实地测试后,利用干扰系数对监测数据进行人工修正,对比结果合格。应用"定点位电解法"监测烧结机烟气中低浓度SO2时,应人工修正或加装剔除CO影响的元件。  相似文献   

3.
《新疆环境保护》1990,12(4):13-18
1989年采暖期对乌鲁木齐市居室内 CO、SO_2、NO_X 和 TSP 浓度,以及吸烟对 CO 浓度影响进行了实际采样分析,并对污染物来源和变化规律作了初步探讨。  相似文献   

4.
使用化学荧光连续监测仪,监测了使用天然气炉具和电炉、电加热器的四户住家室内NO2浓度的24小时变化情况。监测结果表明:燃气炉具的使用可以使厨房中NO2浓度升高,小时均值甚至可达到270ug/m^3,超出《室内空气质量标准》0.24mg/m^3的限值,而电加热器的使用则未发现对室内空气中NO2的浓度有显著贡献。  相似文献   

5.
为研究城市近地面CO浓度变化特征,于2015年1~12月在山东大学开展了CO连续监测试验。结果表明,济南城区CO年均浓度为1.431 mg/m~3。CO表现出明显的双峰型日变化规律,峰值出现在8:00和21:00,谷值出现在15:00。不同季节的CO日变化幅度存在差异,夏季最小,冬季幅度最大。一周之中周末CO浓度要高于工作日时。CO存在明显的季节变化规律,浓度最高值出现在12月,最低值出现在7月份。  相似文献   

6.
本文通过现场实测,获取了在不同行驶工况下深圳市横龙山隧道内CO浓度分布情况.结果表明,在堵车、缓行及正常行驶3种情况下,隧道入口、隧道中及隧道出口的CO浓度均逐渐升高,堵车时隧道内CO浓度最高,正常行驶时的浓度最低.采用环保部机动车排污监控中心关于在用车综合排放因子的研究成果中第3阶段汽车尾气排放标准计算隧道内CO浓度,结果与实测数据相符,CO在纵向全射流通风隧道内扩散规律符合一维纵向空气质量扩散方程.  相似文献   

7.
李亚迅  强建宁 《青海环境》1999,9(3):142-142
根据国标GB13271 —91 规定,在测定锅炉烟尘排放浓度时,过量空气系数α超过18 的,应折算为α等于18 时的烟尘浓度。有时工作中忽视对过量空气系数的测试,使烟尘排放监测值失真。笔者认为应严格按规范操作,监测烟尘排放浓度时,必须测试空气过量系数,再计算锅炉烟尘排放浓度  相似文献   

8.
利用便捷式CO2温度监测仪监测了重庆三峡广场商圈不同地点和时间的大气CO2浓度,采用摄像机记录车流量、人流量及天气状况,采用单因素方差分析和Pearson相关性检验法分析了城市商圈大气CO2浓度时空变化特征及其与各影响因素的相关关系。研究表明,车流量和天气状况是影响城市商圈大气CO2浓度的重要因素,人流量对城市商圈大气CO2浓度的影响不明显。  相似文献   

9.
随着环保观念日益深入人心,人们越来越关心环境污染问题,其中CO在线监测成为主要关注焦点之一。文章基于可调谐半导体激光吸收光谱(TDLAS)技术,利用半导体激光器可调谐性及谐波检测技术原理实现CO气体浓度含量的检测。采用垂直腔面发射激光器(Vertical-Cavity Surface-Emitting Laser,VCSEL)作为可调谐激光光源,使用中心波长位于1565nm附近的半导体激光器,通过波长调制技术对附近的CO吸收谱线扫描,采用多次反射吸收池增加测量光程,从而实现微量CO含量在线测量。通过测试验证表明,该分析仪线性误差≤±1%F.S,重复性1.0%。在环保比对验收中具有较好的准确性,能够有效地对烟气排放的一氧化碳含量进行在线监测。  相似文献   

10.
介绍了置换通风的原理、特性及其发展,分析了数值模拟技术在置换通风的应用。以Fluent软件在暖通空调领域中的应用为例,综述了其对工作区域和非工作区域气流的数值模拟,分析室内污染物浓度分布的变化情况的基本流程。得出利用数值模拟的结果合理安排置换通风对有害物浓度进行控制,使工作区空气质量达到设计要求,而工作区上部区域可以适当超过工作区域的容许浓度,可达到既节能又能保证空气质量的目的。  相似文献   

11.
住宅装修室内环境污染状况调查   总被引:3,自引:0,他引:3  
随着国家经济发展和人民生活水平、生活质量的不断提高,人们更加注重在住房装饰装修上的金钱投入以圆梦中家居。但是,由于现实生活环境的多方因素制约,伴随住宅装修过程形成的室内环境污染也给人们希望获得健康环保的高质量生活带来严重影响。通过对新装修住宅(客厅、主卧室、次卧室)进行室内环境污染检测,获得了非常有益的实测数据。通过统计分析该数据,发现新装修住宅室内空气中的甲醛、苯及TVOC存在普遍超标,且有的情况非常严重,应当引起人们的高度关注。为此建议:装修时要明确目的,树立环保理念,综合规划设计;注意材料质量优选控制污染源头,加强施工监督和检测验收;对污染超标住宅采取必要的治理措施,加强室内通风换气,室内空气质量检测达标后才居住使用,确保居室环境的健康环保。  相似文献   

12.
The potential atmospheric impact of constructed wetlands (CWs) should be examined as there is a worldwide increase in the development of these systems. Fluxes of N(2)O, CH(4), and CO(2) have been measured from CWs in Estonia, Finland, Norway, and Poland during winter and summer in horizontal and vertical subsurface flow (HSSF and VSSF), free surface water (FSW), and overland and groundwater flow (OGF) wetlands. The fluxes of N(2)O-N, CH(4)-C, and CO(2)-C ranged from -2.1 to 1000, -32 to 38 000, and -840 to 93 000 mg m(-2) d(-1), respectively. Emissions of N(2)O and CH(4) were significantly higher during summer than during winter. The VSSF wetlands had the highest fluxes of N(2)O during both summer and winter. Methane emissions were highest from the FSW wetlands during wintertime. In the HSSF wetlands, the emissions of N(2)O and CH(4) were in general highest in the inlet section. The vegetated ponds in the FSW wetlands released more N(2)O than the nonvegetated ponds. The global warming potential (GWP), summarizing the mean N(2)O and CH(4) emissions, ranged from 5700 to 26000 and 830 to 5100 mg CO(2) equivalents m(-2) d(-1) for the four CW types in summer and winter, respectively. The wintertime GWP was 8.5 to 89.5% of the corresponding summertime GWP, which highlights the importance of the cold season in the annual greenhouse gas release from north temperate and boreal CWs. However, due to their generally small area North European CWs were suggested to represent only a minor source for atmospheric N(2)O and CH(4).  相似文献   

13.
Prediction of odor from pig production based on chemical odorants   总被引:1,自引:0,他引:1  
The present work was performed to investigate the use of odorant measurements for prediction of odor concentration in facilities with growing-finishing pigs and to analyze the odorant composition in facilities with different floor and ventilation systems. Air was sampled in Nalophan bags, odor concentrations were measured by dilution-to-threshold olfactometry, and concentrations of odorants were measured by proton-transfer-reaction mass spectrometry (PTR-MS). Olfactometry and chemical analyses were synchronized to take place at identical time intervals after sampling. A principal component analysis revealed that different facilities for growing-finishing pigs can be distinguished based on the odorants. Pit ventilation comprising a small amount of the total ventilation air (10-20%) in facilities with both room and pit ventilation can be used to concentrate odorants, whereas the room ventilation contains lower concentrations of most odorants. A partial least squares regression model demonstrated that prediction of the odor concentration based on odorants measured by PTR-MS is feasible. Hydrogen sulfide, methanethiol, trimethylamine, and 4-methylphenol were identified as the compounds having the largest influence on the prediction of odor concentration, whereas carboxylic acids had no significant influence. In conclusion, chemical measurement of odorants by PTR-MS is an alternative for expressing the odor concentration in facilities with growing-finishing pigs that can be used to increase the understanding of odor from different types of facilities and improve the development of odor reduction technologies.  相似文献   

14.
Since the majority of schools are housed in buildings dating from the 1960s and 1970s, a comprehensive construction and renovation program of school buildings has been carried out to improve the educational conditions in Korea. However, classrooms and computer rooms, with pressed wood desks, chairs and furnishings, as well as construction materials, might have negative effects on the indoor air quality. Furthermore, most schools have naturally ventilated classrooms. The purpose of this study was to characterize the concentrations of different indoor air pollutants within Korean schools and to compare their indoor levels within schools according to the age of school buildings. Indoor and outdoor air samples of carbon monoxide (CO), carbon dioxide (CO(2)), particulate matter (PM(10)), total microbial count (TBC), total volatile organic compounds (TVOCs) and formaldehyde (HCHO) were obtained during summer, autumn and winter from three sites; a classroom, a laboratory and a computer classroom at 55 different schools. The selection of the schools was based on the number of years since the schools had been constructed. The problems causing indoor air pollution at the schools were chemicals emitted by building materials or furnishings, and insufficient ventilation rates. The I/O ratio for HCHO was 6.32 during the autumn, and the indoor HCHO concentrations (mean = 0.16 ppm) in schools constructed within 1 year were significantly higher than the Korean Indoor Air Standard, indicating that schools have indoor sources of HCHO. Therefore, increasing the ventilation rate by means of a mechanical system and the use of low-emission furnishings can play key roles in improving the indoor air quality within schools.  相似文献   

15.
Concentrations of dissolved methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O) were measured in the water columns of non-oxygenated and artificially oxygenated, ice-covered eutrophied lakes in the mid-boreal zone in Finland during late winter 1997 and 1999. Sampling was conducted during winter stratification, the critical period for oxygen (O2) deficiency in seasonally ice-covered, thermally stratified lakes. Oxygen concentrations were maintained at least at a moderate level throughout the oxygenated water columns, whereas the non-oxygenated columns suffered anoxic hypolimnia. The mean concentrations of dissolved CH4 exceeding the atmospheric equilibrium were greater in the non-oxygenated water columns (20.6-154 microM) than in the oxygenated ones (0.01-1.41 microM). In contrast, the mean excess CO2 concentrations varied less between the non-oxygenated and oxygenated sites (0.28-0.47 and 0.25-0.31 mM, respectively). Oxygenated water columns had greater mean excess concentrations of N2O (0.018-0.032 microM) than the non-oxygenated ones (0.005-0.024 microM). If the accumulated greenhouse gas stores in the water columns during winter are assumed to be released to the atmosphere during the spring overturn, the global warming potentials (GWP, time horizon 100 yr) of these potential emissions at the non-oxygenated, eutrophic study sites ranged from 177 to 654 g CO2 equivalent (CO2-e) m-2 compared with 144 to 173 g CO2-e m-2 at the oxygenated sites. The increase in the accumulation of CH4 was the main reason for the higher GWP of the non-oxygenated sites. Anthropogenic eutrophication of lake ecosystems can generate increased CH4 emissions due to associated O2 depletion of their sediment and water column.  相似文献   

16.
成都市城区春节期间燃放烟花爆竹对空气质量的影响   总被引:3,自引:0,他引:3  
利用空气质量自动监测系统分析了2013年春节期间成都市城区的SO2、NO2、CO、O3、PM10及PM2.5的浓度值,发现烟花爆竹的燃放对SO2、NO2、PM10及PM2.5的浓度有较大影响。  相似文献   

17.
为了掌握南充市近年来城市空气质量变化及其达标情况,对南充市城区2008~2012年SO2、NO2和PM10的质量浓度数据进行统计分析,并计算各个站点的空气污染指数和空气质量指数。结果表明,3种污染物浓度值都有明显的下降趋势,S02浓度在0.002~0.052mg/m^3之间变化;N02浓度值从0.042mg/m^3下降到0.029mg/m^3;PM10浓度在0.060~0.063mg/m^3之间波动。南充市空气质量冬季较差,夏季较好。在5个监测点中,炼油厂空气质量最差,优良率为92.9%(85.1%);高坪空气质量最好,优良率为99.1%(98.3%)。相关性分析表明,南充市空气污染源主要是工业燃煤和机动车尾气。  相似文献   

18.
四川省城市环境空气质量及变化趋势   总被引:1,自引:0,他引:1  
邹军  杨柳 《四川环境》2010,29(4):50-53
本文根据2000~2009年四川省24个地级城市例行空气监测数据,按照《环境空气质量标准》(GB3095-1996)中的二级标准,采用综合污染指数法分析了四川省近10年环境空气质量的现状、变化趋势及影响因素。结果表明:从年际变化看,可吸入颗粒物浓度呈下降趋势,二氧化硫、二氧化氮浓度变化较平稳;年内变化显示,各污染物浓度季节变化明显,冬季污染最严重,污染程度由高到低的顺序为冬季、春季、秋季、夏季。全省综合污染指数呈下降趋势,空气污染程度得到了明显缓解,空气质量逐渐变好。  相似文献   

19.
Arsenic, cadmium, chromium, and copper concentrations of the Pacific oyster,Crassostrea gigas, purchased from four different markets were determined in this project. In general, gill tissue had the highest proportion of metal contents (34%–67%) when compared with other tissue parts (mantle, viscera, and adductor muscle), except for arsenic, which showed the highest level in adductor muscle (44%). Smaller oysters (longitudinal length of soft body part less than 6 cm) had higher metal levels than larger ones (longitudinal length of soft body part more than 6 cm), except copper. None of the four metals examined showed an obvious seasonal trend, although cadmium levels seemed to be higher in autumn and winter months. Arsenic, cadmium, and copper levels in oysters purchased from different markets and different months obtained in the present study were higher when compared with past reports. Cadmium levels, as high as 10.98 mg/kg (dry weight basis) have been obtained. This approaches the safety limit that may be hazardous to human health. Continual monitoring of cadmium and other trace metals of toxicological significance to man in Hong Kong seafood is recommended.  相似文献   

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