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1.
在沈阳市选取7个主要公园,于2017年3月采集土壤样品,采用高效液相色谱法对15种美国环保署优控多环芳烃(Polycyclic Aromatic Hydrocarbons,PAHs)的浓度进行分析。结果表明:2017年沈阳市各公园PAHs的污染特征不同,主要污染成分差别明显,其中万泉公园土壤污染水平最高,土样中PAHs浓度远高于其他采样点。由纵向分析发现,沈阳市各公园PAHs浓度随着土壤深度增加呈下降的趋势。由沈阳市各公园土壤样品中PAHs不同环数所占百分比可知,中、高环数污染物组分含量普遍较高而低环数污染物组分含量均较少,表征各公园土壤污染源主要为燃料燃烧。通过比值法进一步分析可知,沈阳市各公园土壤中PAHs来源主要为燃料的高温燃烧,燃烧源主要为煤、石油类、生物质燃烧的混合源。 相似文献
2.
北京市部分地区土壤和植物中多环芳烃的分布 总被引：3，自引：1，他引：3
研究了北京市区东部、东南部和西南部不同功能区土壤和绿化植物中多环芳烃（PAHs）的分布特征，讨论了土壤和植物叶片中多环芳烃质量分数的相关性。结果表明：车流量较多的路边土壤PAHs质量分数很高，西城区北京杨叶片中PAHs质量分数较高；相同采样点的土壤与植物叶片中多环芳烃的质量分数相关显著。 相似文献
3.
在南京市浦口和大厂的五大主要功能区（工业区、交通干线、居民区、蔬菜生产基地和风景区）分别布置采样点,共采集了75个菜地耕层土壤样品,以Cd、Cu、Pb和Zn等典型污染重金属元素的全量数据为基础,运用经典统计分析、综合污染指数和地统计分析相结合的方法对土壤重金属污染进行评价。结果表明,Cd、Cu和Zn分别超出其南京地区土壤背景值的5．42、1．84和1．14倍,Pb未超出。不同功能区菜地土壤的重金属全量水平存在明显差异,其中工业区菜地土壤的重金属污染较为严重。对于Cd和Cu,单因子污染指数大于1的样点数达100％,Zn为52％,Pb为2．67％。研究区内菜地土壤重金属的综合污染指数为4．12,属于中度污染。Cu的空间相关性很弱,Cd、Pb和Zn具有中等的空间结构性;四种重金属的空间相关尺度较为接近。Cd、Cu和Zn的单因子污染指数具有相似的空间分布,总体呈现出南高北低的带状递减趋势,且高峰值具有空间分布的趋同性,而Pb的单因子污染指数分布呈现西北和东南两端高,中间较低的趋势。综合污染指数的空间分布显示,研究区大部分菜地土壤处于中度重金属污染水平,钢铁生产厂周边的斑块状区域重金属污染更加严重。 相似文献
4.
在辽河的干支流选择12个例行监测断面,分别于2007年8月和11月采集水样,分析16种US EPA（美国环保署）优控多环芳烃（PAHs）的浓度变化。结果表明：辽河丰水期16种PAHs总量的浓度范围为216—848 ng/L,平均值为430 ng/L,枯水期16种PAHs总量的浓度范围为221—1360 ng/L,平均值为660 ng/L。特征指数表明,辽河水中PAHs主要来源于燃料的高温不完全燃烧,燃烧源为机动车、煤和生物质等。 相似文献
5.
银川市大气颗粒物物理化学特征研究Ⅰ:大气颗粒物浓度特征 总被引：3，自引：3，他引：3
根据大量的大气环境监测资料,系统分析了银川市市区、郊区以及市中各功能区(居民区、商业区、文教区、工业区、交通区、娱乐区)大气颗粒物的TSP(TotalSuspendedParticles)、PM10(粒径小于等于10μm的粒子)和PM2.5(粒径小于等于2.5μm的粒子)质量浓度的季节分布、日变化以及随高度的分布特征。结果表明:银川市背景大气TSP平均值为0.126～0.248mg·m-3,低于国家三级污染标准;银川市区TSP日平均浓度的年平均值为0.47～0.78mg·m-3,超过国家二级标准0.57～1.6倍,超标率高达61.3%～92.5%,日均最大值超标7.9倍;春夏秋冬4季中,以冬春两季日平均浓度最高,其原因是燃煤取暖和沙尘暴多发。各功能区中商业区、交通区、居民区的TSP较高,这显然与人为活动、机动车辆排放密切相关,TSP日变化均呈现出与人为活动相一致的规律性;TSP的空间分布表明城市高于郊区,规模大、人口密度高、商业网点密集的城区TSP较高。各粒径粒子的质量浓度随高度递减,PM10占TSP的比例却随高度增加,说明PM10随高度增加。地面呼吸带高度上PM10和PM2.5均较高,可能与低空排放源有关。春季风沙期是大气污染最为严重的季节。 相似文献
6.
2006—2008年上海地区臭氧污染特征与评价指标研究 总被引：11，自引：0，他引：11
利用2006—2008年上海市的徐汇、浦东、宝山、金山、崇明5个监测站的臭氧观测资料,分析了上海地区的臭氧污染现状。从空间分布上来看,基本呈现中心城区低、郊区高的特征,宝山钢铁工业区较低而金山化工区较高;从时间分布上来看,3—11月均会出现臭氧浓度超标,7月臭氧超标天数最多,5月和8月的超标天数也较多。一天内小时平均浓度超标(100 ppbv;国家环境空气质量标准)最多的时段为13—15时,而8小时平均浓度超标(75 ppbv;美国EPA标准)最多的时段是9—10时;根据WHO、欧盟、美国和我国环境空气质量标准(简称我国标准)及上海市气象局气象灾害臭氧预警信号(简称上海市标准)所统计的上海地区各监测站点超标天数可知,WHO标准统计的超标天数最多,其次为欧盟,按我国标准和上海市标准所统计出的臭氧超标天数最少。8小时滑动平均统计的臭氧超标天数比按小时平均浓度统计的超标天数要多一倍左右。从保护人体健康的角度来看,用臭氧8小时平均来评价臭氧污染程度更为科学,采用小时平均浓度设定臭氧评价阈值进行污染预警和管理更具可操作性。 相似文献
7.
8.
了解涂装行业挥发性有机物（VOCs）的排放特征是制定山东地区臭氧（O3）和PM2.5防控策略的重要环节.本研究在山东地区测定了两家典型食品金属包装企业喷涂过程中VOCs的排放组成,企业产品以饮料罐和罐头为主.结果表明：两家企业排放的总VOCs质量浓度水平相当,质量浓度变化范围在50~1 500 μg/m3;但两家企业喷涂过程中VOCs的排放组成具有一定的差异,以生产铝罐和马口铁罐为主的企业中的含氧挥发性有机物（OVOCs）含量最多,占比89.71%（质量分数,下同）;而生产铝罐的企业芳香烃（56.15%）是首要的排放种类,其次是OVOCs （32.32%）.通过分析两家企业内外喷涂工艺的VOCs源成分谱,发现同一企业不同工艺之间有一定差异,多种罐生产企业的内、外喷涂中乙醇占比最高,分别为94.28%、84.46%;单铝罐生产企业的内喷涂2-丁酮（24.33%）是重要组分,外喷涂中甲苯（36.40%）含量较高. 相似文献
9.
通用陆面模式对土壤质地和亮度的敏感性分析 总被引：6，自引：2，他引：4
使用前苏联Valdai 1966～1971年的气象观测资料,研究了通用陆面模式(Common Land Model,CoLM)模拟的水分循环和地表通量在12种土壤质地和8种土壤亮度条件下的差异。结果表明,在相同的气象条件下,模拟的热通量对土壤质地和亮度都比较敏感,而地表水文过程只对土壤质地敏感。土壤亮度相同时,相对砂性土壤,粘土含量高的土壤保水性强,土壤湿度、地表蒸发和径流量都比较大（月均最大差值：土壤湿度约为5 kg·m-2,地表蒸发和径流量约为年降水量的7%和1.2 %）,相应地在热通量分配上存在明显差异（月均最大差值为8 W·m-2）;土壤质地相同,亮度由亮变暗时,潜热通量变化很小,地表温度略有升高,而感热通量和净辐射增加显著（月均最大差值为7 W·m-2）。土壤质地和亮度对模拟的影响主要存在于降水少、植被覆盖度低的3～5月。 相似文献
10.
利用ＷＰＳ（宽范围颗粒粒径谱仪）、Ａｎｄｅｒｓｏｎ Ⅱ型９级撞击采样器测量了２００８年夏季典型日南京钟山风景区、鼓楼商业区与江北工业区大气气溶胶数浓度谱分布和质量浓度,分析了城市不同功能区气溶胶粒子的分布特征．结果表明：各功能区大气颗粒物浓度均比较高,达到１０４ｃｍ－３,数浓度谱均为单峰型,峰值集中在００１～００４μｍ;其中气溶胶粒子数浓度主要集中在００１～０２μｍ粒径范围内,其日变化受汽车尾气排放、混合层高度变化的影响较大,且呈现明显的双峰型;粒径为００１～０１μｍ的超细粒子对总数粒子贡献较大,鼓楼为９３２８％,江北为８１６６％,钟山为６６５２％;细粒子（粒径＜１１μｍ）与ＴＳＰ质量浓度的比值钟山为９２％,鼓楼３３７７％,
江北２４９８％;质量浓度主要为粗粒子（粒径≥１１μｍ）贡献,但是鼓楼与江北的细粒子的贡献也非常大,说明这两个功能区的细粒子的污染值得关注;数浓度和相对湿度（ＲＨ）有密切联系,当ＲＨ＜７５％时其峰值随着相对湿度的增大而增大,当ＲＨ＞７５％时其峰值随着相对湿度的增大而减少,并且相对湿度对细粒子的影响要大于对大粒子的影响． 相似文献
11.
多环芳烃来源与分布及迁移规律研究概述 总被引：14，自引：0，他引：14
概述了多环芳烃的来源,就近年来多环芳烃(PAHs)在大气、土壤、植被和水体沉积物中分布与迁移规律的研究成果进行了综述,并展望了未来PAHs研究方向。 相似文献
12.
为了研究青海瓦里关和西宁PM10中多环芳烃污染特征及其来源,于2007年5月24日～6月1日在青藏高原东北部的瓦里关大气本底站和青海气象台进行了观测并各采集7组气溶胶样品,分析了PM10质量浓度、粒径分布和多环芳烃谱分布特征。结果表明,瓦里关PM10日均浓度为24.85μg.m-3,粒径分布呈三模态;西宁PM10日均浓度为65.25μg.m-3,呈明显双模态。瓦里关积聚态颗粒物质量百分比大于西宁观测点。瓦里关PM10中多环芳烃含量远低于同季节西宁地区,浓度值为8.38ng.m-3;高分子量的PAHs主要集中在细颗粒上,而粗颗粒上低分子量PAHs相对较多。两地区高分子量多环芳烃均为单峰分布。后向轨迹分析表明,瓦里关PM10中PAHs污染与西宁市以及黄河河谷工业带方向的输送密切相关。 相似文献
13.
利用自行组装的烟气采集装置,研究了TiO2对香烟烟气中多环芳烃(PAHs)光催化降解的效果.运用气质联用仪,对烟气中的多环芳烃进行分析,结果表明TiO2和光对多环芳烃光降解效果随环数变化有不同的变化趋势,TiO2的量是决定低环多环芳烃降解效率的主要因素;紫外辐射强度是决定高环多环芳烃降解效果的主要因素.在弱紫外辐射条件下,TiO2的量由3g增加到6g时,低环多环芳烃降解效率提高38.7%;在固定TiO2为3g时,紫外辐射强度增强1倍使高环多环芳烃降解效率提高87.2%;在强紫外辐射条件下,TiO2的使用会降低低环多环芳烃的光催化降解效率,TiO2分别为3g和6g时,低环多环芳烃降解效率分别下降76.9%和72.4%;在3gTiO2条件下,苯并[a]芘的催化降解效果最好,效率提高83.5%. 相似文献
14.
Polycyclic aromatic hydrocarbons and their molecular diagnostic ratios in urban atmospheric respirable particulate matter 总被引：2，自引：5，他引：2
María del Rosario Sienra Nelson G. Rosazza Margarita Prndez 《Atmospheric Research》2005,75(4):267-281
Atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs) in Santiago de Chile city were evaluated to study particulate PAHs profiles during cold and spring weather periods. Urban atmospheric particulate matter PM10 was collected using High Volume PM10 samplers. Fifteen samples of 24 h during austral winter and 20 samples of 24 h during spring, 2000 were collected at two sampling sites (North–East and Central areas of the city) whose characteristics were representative of the prevailing conditions. Seventeen PAHs were quantified and total PAHs concentration ranged from 1.39 to 59.98 ng m−3, with a seasonal variation (winter vs. spring ratio) from 0.5 to 12.6 ng m−3. Molecular diagnostic ratios were used to characterize and identify PAHs emission sources such as combustion and biogenic emissions. Results showed that the major sources of respirable organic aerosol PM10 in Santiago are mobile and stationary ones. 相似文献
15.
The differences of the size distribution of polycyclic aromatic hydrocarbons (PAHs) between urban and rural sites of Guangzhou, China 总被引：11，自引：1，他引：11
Size distribution aerosol samples collected at two urban locations (Liwan and Wushan) and a suburban location (Xinken) in Guangzhou (South China) in autumn using a MOUDI (Micro-orifice Uniform Deposit Impactor) have been analyzed for 13 polycyclic aromatic hydrocarbons (PAHs) by gas chromatography with mass selective detection (GC-MS). Different PAH size distribution models were found for urban locations and a suburban location. The particle size distributions of PAHs tend to shift toward a larger size in a suburban location than in an urban location caused by aerosol aging processes. The ratios of total-PAH/TSP changed greatly during different sampling periods, even though the samplings were conducted consecutively. This can be the result of reactions between PAHs and atmospheric photooxidants, and the formation of SOAs (secondary organic aerosols) during the aging process. Adsorption behavior on available aerosol surface area, absorption behavior in available aerosol organic mass and multilayer adsorptive accumulation in coarse mode aerosols were the three mechanisms which control the size distribution of PAHs. 相似文献
16.
The concentrations of n-alkanes and polycyclic aromatic hydrocarbons (PAHs) are determined in atmospheric aerosol samples collected at a rural sampling site in Hungary. For the n-alkanes the chromatographic profiles are established and the average carbon number and carbon preference index (CPI) are calculated. An attempt is made to obtain the origin of n-alkanes found in atmospheric aerosol samples. Based on the results of the measurements the probable importance of a round-the-year biogenic source for the n-alkanes with CPIs close to unity is emphasized. 相似文献
17.
The sources and seasonal variations of organic compounds in PM<Subscript>2.5</Subscript> in Beijing and Shanghai 总被引：1，自引：0，他引：1
Yilun Jiang Ximei Hou Guoshun Zhuang Juan Li Qiongzhen Wang Rong Zhang Yanfen Lin 《Journal of Atmospheric Chemistry》2009,62(3):175-192
Fine aerosol samples were collected throughout spring, summer, and winter in 2004∼2005 at a major urban traffic junction (BNU)
and a suburban location (MY) in Beijing and at a downtown site (SH) in Shanghai, China. Ten of the 16 EPA priority polycyclic
aromatic hydrocarbons (PAHs), seven fatty acids, levoglucosan, and cholesterol were identified and quantified. PAHs detected
in Beijing and Shanghai were up to one order of magnitude higher than those reported in the developed countries either in
urban or suburban areas, while levoglucosan was one order of magnitude lower than that in other countries for no biomass combustion
in domestic heating in the mega-cities in China. PAHs showed the same seasonal trend in all sampling sites as the highest
in winter and the lowest in summer, while fatty acids no pronounced seasonal variation. A significant fraction of levoglucosan
from cooking with higher concentrations in urban than in suburban area contributed to the ambient atmosphere, indicating that
the main source of levoglucosan in urban environment would be cooking rather than biomass burning. The relative contributions
of coal combustion and vehicle exhaust sources to PAHs in fine aerosols were preliminarily estimated to be 1:2 in Beijing
and 1:1 in Shanghai, revealing that the air pollution in these mega-cities in China was mainly the mixing of coal combustion
with vehicle exhaust. Cooking was one of the major sources of organic aerosols in both Beijing and Shanghai. 相似文献
18.
This work studied the influence of meteorological conditions on particulate polycyclic aromatic hydrocarbons (PAHs) in the atmosphere of Higashi Hiroshima, Japan. The seasonal variation of particulate PAHs was also covered. It was found that ambient temperature, solar intensity and weekly rainfall had significant influence on the particulate PAH concentration based on correlation studies. Correlation of particulate PAHs with ambient temperature, solar intensity, weekly rainfall, wind speed and humidity was studied by using Pearson correlation analysis. Particulate PAHs had a strong negative correlation with ambient temperature and solar intensity. A moderate negative correlation with weekly rainfall was also observed. There was no significant correlation between particulate PAHs with wind speed as well as humidity. Besides, particulate PAHs were found to have significant positive correlation with sulfur dioxide and nitrogen dioxide while having a moderate negative correlation with ozone. The particulate PAHs in Higashi Hiroshima exerted distinct seasonal variation with a higher concentration in winter and lower concentration in summer. When compared among PAHs with different numbers of aromatic rings; 5-ring PAHs was found to exert the most distinct seasonal variation. The contribution of carcinogenic PAHs to total particulate PAH concentration was fairly constant at about 50% throughout the year. 相似文献
19.
S. A. Reznikov O. V. Yakunina A. A. Matveev N. N. Luk’yanova I. V. Bogush R. A. Adzhiev 《Russian Meteorology and Hydrology》2018,43(5):332-339
The results of long-term biogeochemical monitoring of Lake Baikal are presented. The accumulation is studied of polycyclic aromatic hydrocarbons (PAHs) in bottom sediments and macrozoobenthos that were synchronously sampled at the same stations. The stations are located in the areas where anthropogenic impact on the lake is high: in the area of the former Baikal Pulp and Paper Mill (BPPM), in the footprint of the BAM railway in the north of the lake and in the Selenga River delta front as well as in the zones of coastal fouling in the area of BPPM. It is found that variations in the concentration of PAHs in macrozoobenthos do not directly depend on those in the sediments. It is revealed that the maximum concentration of benzo[a]pyrene in the area of the former BPPM is almost by eight times higher than in the other areas of the lake; shallow-water macrophytes accumulate more polyarenes than deep-water macrozoobenthos. 相似文献
20.
Influence of UV-B Radiation and Temperature on Photodegradation of PAHs: Preliminary Results 总被引：2，自引：0，他引：2
Martí Nadal Jason J. Wargent Kevin C. Jones Nigel D. Paul Marta Schuhmacher José L. Domingo 《Journal of Atmospheric Chemistry》2006,55(3):241-252
The joint impact of UV-B radiation and temperature on photodegradation of polycyclic aromatic hydrocarbons (PAHs) sorbed to an organic solvent was assessed in this study. This approach was experimentally performed in a laboratory investigation by means of comparison of two different environments: Atlantic (Lancaster, UK) and Mediterranean (Tarragona, Catalonia, Spain) climatic conditions. The concentration of 10 PAHs contained in a tetradecane solution was compared under two different temperatures (10 and 20°C) and UV-B doses (6.5 and 22.5 kJ m−2 day−1). No photodegradation was observed for the heaviest hydrocarbons (benzo(a)anthracene, chrysene, benzo(a)pyrene, dibenzo(g,h,i)perylene and coronene). In general terms, the half-life of PAHs was highly dependent on their molecular weight. Significant faster photodegradation rates were detected specially for light PAHs. It indicates that a synergistic effect occurred when both temperature and UV-B dose increased. This synergism might have a great implication on the long-range transport of environmental organic pollutants taking into account that low-latitude areas are the hottest and most irradiated of the planet. 相似文献