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沙尘暴对大连市空气质量影响的判别研究 总被引:2,自引:1,他引:1
利用二次因子分析法对大连市区5个大气自动监测点住所测的四种污染因子(CO、SO2、NOx、PM10)和风速(1997~2004年)资料数据进行分析,分析了当地污染排放累积和外来输送两种主要原因,对大连市空气质量的影响.通过进一步对CO、NOx、PM10因子得分之差(FS2-FS1)的分析,找出了适合确定沙尘暴对大连市空气质量影响的判据,即(FS2-FS1)>0 相似文献
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机动车排气污染对城市道路空气质量的影响 总被引:1,自引:0,他引:1
通过对南京市珠江路道路空气质量的监测,掌握了机动车排气污染对街道空气质量的影响,分析了道路中NOx、NO2、CO的变化规律,以及污染物与车流量和大气扩散条件的关系.并通过与城市大气自动监测国控点监测数据的比较,得出国控点NOx、NO2浓度和道路中NOx、NO2浓度变化趋势一致. 相似文献
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杭州市酸雨污染现状及成因分析 总被引:10,自引:0,他引:10
对杭州市1998年—2002年的降水监测数据进行了统计分析。结果表明,2002年杭州市区酸雨频率为73.6%,降水pH均值为4.68,临安酸雨频率高达97.5%,降水pH均值为4.04,其余几个县(市)降水酸度均<5.60。杭州市有82.1%面积属重酸雨区。指出,杭州市气象条件不利于大气中SO2、NOx的扩散,土壤扬尘不能对酸雨的形成起有效的缓冲作用,因此只有通过调整能源结构,从源头控制煤质(含硫量),严格控制机动车尾气污染,以减少SO2、NOx排放量。 相似文献
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于2003年12月-2004年11月对平顶山市城区大气PM10、PM2.5污染进行了调查.结果表明,2004年大气PM10、PM2.5质量浓度分别为0.031 mg/m3~0.862 mg/m3、0.019 mg/m3~0.438 mg/m3;年均值分别为0.174 mg/m3、0.114 mg/m3,超标0.74倍、6.60倍.PM10、PM2.5污染的季节变化趋势是以冬季、春季高,秋季次之,夏季最低,细颗粒(PM2.5)约占PM10 65%;As、Pb、Cd、S、Zn、Cu、Mn、Ca等元素是颗粒物中主要污染元素,易在PM2.5中富集.平顶山市大气颗粒物污染的主要来源有煤炭燃烧、汽车尾气、城市基础建设和有色金属冶炼行业. 相似文献
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室内外空气污染对学龄儿童呼吸系统影响的研究 总被引:6,自引:0,他引:6
通过对污染区和对照区 2 0 0 0多名学龄儿童呼吸系统症状、疾病患病率比较 ,并运用非条件 Logistic回归分析方法 ,就室内外空气污染对学龄儿童呼吸系统健康的影响 ,进行了研究。结果显示 ,污染区室内外空气污染较严重 ,大气中TSP、SO2 和 NOx 的浓度均超过国家二级标准 ,其儿童呼吸系统症状、疾病患病率明显高于对照区。对儿童呼吸系统发病有显著影响的环境因素是 :大气污染、被动吸烟、家庭燃煤、冬季取暖和室内油烟污染程度。其中咳嗽与以上五个因素有显著的正相关关系 (P<0 .0 5) ;除被动吸烟外 ,支气管炎与其它四个因素呈显著正相关 (P<0 .0 5) ;咳痰与大气污染、被动吸烟、冬季取暖和室内油烟污染程度 ,气喘和呼吸系统疾病住院率与大气污染和室内油烟污染正相关关系显著 (P<0 .0 5)。哮喘与室内外空气污染无显著的统计学联系 相似文献
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为了研究北京大气颗粒物和二■英(PCDD/Fs)的污染状况以及评估交通限行对大气颗粒物和PCDD/Fs的影响。利用同位素稀释高分辨率气相色谱/高分辨率质谱(HRGC/HRMS)联用法和USEPA 1613B标准方法,以中国地质大学(北京)东门为采样点,采集大气PM_(2.5)、PM_(10)、TSP样品,对北京市交通限行期间以及交通限行前后等不同交通状况下颗粒物浓度及大气PM_(2.5)中17种2,3,7,8-PCDD/Fs污染特征进行了监测。结果表明,PM_(2.5)、PM_(10)、TSP的日均质量浓度在交通限行前分别为126、202、304μg/m~3,限行期间分别为39、78、93μg/m~3,限行结束后分别为79、126μg/m~3。PM_(2.5)中17种PCDD/Fs的质量浓度(毒性浓度) 3个时段分别为1 804 fg/m~3(70 fg I-TEQ/m~3)、252 fg/m~3(9 fg I-TEQ/m~3)和1 196 fg/m~3(48 fg I-TEQ/m~3)。北京市交通限行期间颗粒物浓度和二■英浓度显著低于交通限行前后,交通源减排措施的实施是大气颗粒物和二■英污染水平降低的主要原因,从减排效果看,交通源减排措施对大气细颗粒物(PM_(2.5))的控制效果明显好于大气粗颗粒物。 相似文献
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钼矿区周边农田土壤中重金属污染状况的分析与评价 总被引:4,自引:1,他引:3
对钼矿区周边农田土壤重金属污染情况进行了详细研究.选择该矿区受污染农田土壤样本80个,采用HNO3-HF-HClO4混酸对土壤样品进行处理,运用欧共体参比司推荐的BCR三步连续提取法进行化学形态分析;使用等离子体发射光谱仪(ICP-AES)测定土壤样品中Mo、Pb、As、Hg、Cr、Cd、Zn、Cu、Ni的全量及各种化学形态的含量并进行评价,同时对矿区地下水进行分析;采用spas软件进行数据分析.结果表明,矿山周边农田土壤重金属主要污染物为Cd、Hg并伴有Cr污染;Nemerow综合指数6.81,综合评价结果为该区土壤已受严重污染;Cd与As污染来源基本相同,Cu、Ni、Zn污染来源基本相同,Hg有独立的污染来源;重金属中化学形态分布为残余态>有机结合态>氧化结合态>酸可提取态;重金属Cr及Hg的有效态比例较大,可能会影响农作物的正常生长;矿山周边农田土壤重金属污染的原因可能是污染地下水的浇灌,矿石的开采、运输和大气降尘等过程;有机农药及塑料农用制品的施用过程,自然成土、矿物的伴生及其转化等过程. 相似文献
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灰霾期间武汉城市区域大气污染物的理化特征 总被引:2,自引:2,他引:0
利用湖北省大气复合污染自动监测站2013年的全年监测数据,分析了灰霾期间武汉城市区域大气污染物的理化特征。霾日主要出现在春季、秋季和冬季。霾日与非霾日大气污染物质量浓度和气象参数的对比分析结果显示:高湿度、静风是武汉城市区域霾日的重要气象特征;PM1、PM_(2.5)、PM_(10)、NO_2、CO、NH3的质量浓度,SOR、NOR值以及PM_(2.5)中的二次无机离子(SO2-4、NO-3、NH+4)和部分元素(Pb、Se、Cd、Zn、K)的质量浓度均在霾日明显高于非霾日,而霾日SO2质量浓度仅在冬季略高于非霾日。选取2013年1月的连续灰霾日进行相关性分析,结果表明:污染组分主要来自当地排放(包括直接排放和二次形成),并受当地气象条件影响。此次灰霾过程中PM_(2.5)中的硫酸盐和硝酸盐主要来自气相反应,气态NO_2主要生成了气态HNO_3,而不是HNO_2。 相似文献
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Jing Zhou Jian Cui Jian-ling Fan Jia-ni Liang Ti-jian Wang 《Environmental monitoring and assessment》2010,163(1-4):105-113
Atmospheric dry deposition is an important nitrogen (N) input to farmland ecosystems. The main nitrogen compounds in the atmosphere include gaseous N (NH3, NO2, HNO3) and aerosol N (NH4 +/NO3 ?). With the knowledge of increasing agricultural effects by dry deposition of nitrogen, researchers have paid great attention to this topic. Based on the big-leaf resistance dry deposition model, dry N deposition velocities (V d) in a typical red soil agro-ecosystem, Yingtan, Jiangxi, Southeastern China, were estimated with the data from an Auto-Meteorological Experiment Station during 2004–2007. The results show that hourly deposition velocities (V dh) were in the range of 0.17–0.34, 0.05–0.24, 0.57–1.27, and 0.05–0.41 cm/s for NH3, NO2, HNO3, and aerosol N, respectively, and the V dh were much higher in daytime than in nighttime and had a peak value around noon. Monthly dry deposition velocities (V dm) were in the range of 0.14–0.36, 0.06–0.18, and 0.07–0.25 cm/s for NH3, NO2, and aerosol N, respectively. Their minimum values appeared from June to August, while their maximum values occurred from February to March each year. The maximum value for HNO3 deposition velocities appeared in July each year, and V dm(HNO3) ranged from 0.58 to 1.31 cm/s during the 4 years. As for seasonal deposition velocities (V ds), V ds(NH3), V ds(NO2), and V ds(aerosol N) in winter or spring were significantly higher than those in summer or autumn, while V ds(HNO3) in summer were higher than that in winter. In addition, there is no significant difference among all the annual means for deposition velocities (V da). The average values for NH3, NO2, HNO3, and aerosol N deposition velocities in the 4 years were 0.26, 0.12, 0.81, and 0.16 cm/s, respectively. The model is convenient and feasible to estimate dry deposition velocity of atmospheric nitrogen in the typical red soil agro-ecosystem. 相似文献
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Transformation of nitrogen dioxide into ozone and prediction of ozone concentrations using multiple linear regression techniques 总被引:1,自引:0,他引:1
Nurul Adyani Ghazali Nor Azam Ramli Ahmad Shukri Yahaya Noor Faizah Fitri MD Yusof Nurulilyana Sansuddin Wesam Ahmed Al Madhoun 《Environmental monitoring and assessment》2010,165(1-4):475-489
Analysis and forecasting of air quality parameters are important topics of atmospheric and environmental research today due to the health impact caused by air pollution. This study examines transformation of nitrogen dioxide (NO2) into ozone (O3) at urban environment using time series plot. Data on the concentration of environmental pollutants and meteorological variables were employed to predict the concentration of O3 in the atmosphere. Possibility of employing multiple linear regression models as a tool for prediction of O3 concentration was tested. Results indicated that the presence of NO2 and sunshine influence the concentration of O3 in Malaysia. The influence of the previous hour ozone on the next hour concentrations was also demonstrated. 相似文献
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中国城市臭氧的形成机理及污染影响因素研究进展 总被引:1,自引:0,他引:1
中国城市臭氧(O_3)污染问题日趋严重。O_3主要来源于汽车尾气及工业排放氮氧化合物(NO_x)和挥发性有机物(VOCs)光化学反应生成,少部分来自于平流层的向下传输。文章介绍了城市O3形成机理研究情况,概述了中国城市臭氧污染浓度特征及气象因子、气候变化、前体物等影响因素研究进展情况,并对未来研究方向进行了展望。 相似文献
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Sixty five samples were taken with a Transition Flow Reactor (TFR) for the measurement of nitric acid (HNO3) and nitrate particulates (NO
3
−
), in a central Athens street having a heavy traffic density, between February 1989 and February 1990. It was established
that the TFR theory overestimated HNO3 and underestimated NO
3
−
. This is caused by the retention of a fraction of the NO2 and a fraction of the HNO2 as NO
2
−
on the sampler's nylon linear. NO
2
−
is in turn oxidized to NO
3
−
and this is determined as HNO3. Two modifications of the TFR theory are proposed for a better estimation of the HNO3 and NO
3
−
. With the first modification HNO3 is estimated as being equal to the smaller of two values: HNO3 TFR and the value calculated if it is considered that 91% of HNO3 is retained by the nylon filter. The second modification was based on the quantification of the effect of NO2 on the concentrations of HNO3 and NO
3
−
. This modification is an improvement on the first one and enables the calculation of a lower limit for the concentration
of HNO2. Both modifications improve the accuracy of the TFR sampler in measuring HNO3 and NO
3
−
, without altering it structurally. It was also found that the nylon filter partially retains some NH3, causing a negative error in the measurement of NH
4
+
with the TFR. The extent of NH3 retention on the nylon filter is proportional to the HNO3 concentration. This error must be taken into account whenever NH
4
+
is being determined. 相似文献
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Reich S Magallanes J Dawidowski L Gómez D Groselj N Zupan J 《Environmental monitoring and assessment》2006,119(1-3):441-457
Air pollutant concentrations from a monitoring campaign in Buenos Aires City, Argentina, are used to investigate the relationships between ambient levels of ozone (O3), nitric oxide (NO) and nitrogen dioxide (NO2) as a function of NO
x
(=NO + NO2). This campaign undertaken by the electricity sector was aimed at elucidating the apportionment of thermal power plants to air quality deterioration. Concentrations of carbon monoxide (CO) and sulphur dioxide (SO2) were also registered. Photo stationary state (PSS) of the NO, NO2, O3 and peroxy radicals species has been analysed. The ‘oxidant’ level concept has been introduced, OX (=O3 + NO2), which varies with the level of NO
x
. It is shown that this level is made up of NO
x
-independent and NO
x
-dependent contributions. The former is a regional contribution that equates the background O3 level, whereas the latter is a local contribution that correlates with the level of primary pollution. Furthermore, the anticorrelation between NO2 and O3 levels, which is a characteristic of the atmospheric photo stationary cycle has been verified.The analysis of the concentration of the primary pollutants CO and NO strongly suggests that the vehicle traffic is the principal source of them. Levels of continuous measurements of SO2 for Buenos Aires City are reported in this work as a complement of previously published results. 相似文献
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Hatzianastassiou N Katsoulis BD Antakis B 《Environmental monitoring and assessment》2007,128(1-3):447-464
In the present study, we investigate the variation of NO
x
(NO + NO2) and O3 concentrations and the relation between the extreme events (episodes) of NO
x
and O3 concentrations and the relevant meteorological conditions in the urban atmosphere of the Athens basin. Hourly data of NO,
NO2 and O3 concentrations from 10 representative monitoring sites located in the Athens basin were used, covering the 10-year time period
from 1994 to 2003. The results of our analysis show that the concentrations of air pollutants differ significantly from one
monitoring site to another, due to the location and proximity of each station to the emission sources. For each site, there
are also significant differences in NO
x
and O3 concentrations from day to day, as well as from month to month and/or from season to season. The annual and seasonal variations
show higher NO values in winter and lower in summer. On the contrary, NO2 and O3 values are higher in summer (photochemical production of O3) and lower in winter. These differences are attributed, to a large extent, to the prevailing synoptic and meteorological
conditions, the most important between them being the wind direction and speed as well as the atmospheric pressure. Our analysis
of the identified 179 extreme NO
x
air pollution events shows that most of them took place under anticyclonic conditions, associated with calm or weak winds
(speed <2.5 ms−1) of mostly southern to southwestern directions, as well as with low air temperatures and intense stable surface atmospheric
conditions. There exists a significant decreasing tendency in NO
x
air pollution episodic events over the 10-year study period, resulting in very few to none events in the period from 2000
to 2003. As far as it concerns the extreme O3 concentrations, 34 air pollution events were identified, occurring under high air temperatures, variable weak winds and intense
solar irradiation. The trends of O3 concentrations are stronger in suburban sites than in urban ones. 相似文献