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1.
石家庄市春节期间大气颗粒物有机碳和元素碳的变化特征   总被引:3,自引:2,他引:1  
为研究石家庄市大气颗粒物的污染特征及其来源,于2013年2月6—19日春节期间在石家庄市采集大气颗粒物TSP、PM10、PM2.5样品,对其有机碳、元素碳进行分析测定。结果表明,石家庄TSP、PM10、PM2.5日平均质量浓度分别为389、330、245μg/m3,颗粒物污染严重;碳组分在颗粒物中占有较大比重,且随着粒径的减少,碳组分比重逐渐增加;存在不严重的次生有机碳污染;OC与EC的相关系数较高,说明两者有较为相似的污染源,主要为燃煤、机动车排放源。各种气象条件对PM2.5、OC、EC浓度和OC/EC的变化都有不同程度的影响。  相似文献   

2.
贵州农村地区室内空气质量及细颗粒物污染特征   总被引:1,自引:0,他引:1  
对贵州农村地区燃煤和燃柴典型村进行了室内外空气质量的监测,并对其中细颗粒物PM2.5的特征进行了研究。结果表明:燃煤家庭厨房和卧室PM2.5分别超过《环境空气质量标准》GB 3095—2012中标准限值(75μg/m3)的1.97、1.41倍,燃柴家庭分别超标0.74、0.06倍,而SO2、CO、NOx均低于标准限值。PAHs以燃煤村厨房最高,为53.92 ng/m3,燃柴村厨房为10.34 ng/m3,2种燃料所致PAHs均以中高环组分为主,对人体健康产生较大风险。PM2.5中氟和砷含量较低,低于参考浓度限值。燃煤村和燃柴村厨房内氟均值分别为0.14、0.11μg/m3,砷平均值分别为0.020、0.014μg/m3。需采取炉灶/燃料改良干预措施来降低农村室内空气污染物浓度,保障居民身体健康。  相似文献   

3.
平顶山市大气PM10、PM2.5 污染调查   总被引:1,自引:4,他引:1       下载免费PDF全文
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   

4.
南京2013年12月初持续重污染天气特征及成因分析   总被引:1,自引:0,他引:1  
利用空气质量监测及气象观测数据,对2013年12月初南京市持续重污染天气特征及成因进行分析,结果表明:此次过程表现出污染程度重、持续时间长及细颗粒物占比大等特征,其中PM2.5日均质量浓度最高达327μg/m3,超标3.36倍;各化学组分中二次无机盐(SNA)占比高达53.8%,且随着污染加重呈增大趋势;有机碳(OC)/无机碳(EC)比值平均为3.7,二次污染特征显著。分析此次污染成因,一方面是冷空气强度弱及大气静稳等气象条件不利于污染扩散;另一方面本地污染排放叠加区域输送影响,造成细颗粒物积聚增多,形成持续重污染天气。  相似文献   

5.
对"十三五"期间哈尔滨市空气质量状况、变化特征及影响因素进行分析,为哈尔滨市打赢蓝天保卫战提供科学参考。以哈尔滨市为研究区域,基于哈尔滨市12个国控监测点位监测结果,对"十三五"期间哈尔滨市环境空气质量优良天数及6项污染物进行分析,总结了环境空气质量变化特征及影响因素。结果表明:"十三五"期间,哈尔滨市环境空气质量呈现波动向好趋势,较"十二五"期间大幅改善,除细颗粒物外,其他指标已稳定达二级标准,臭氧成为仅次于细颗粒物的首要污染物,冬季燃煤污染是环境空气最主要的污染来源,秋季秸秆焚烧及春季清除秸秆根茬也会产生一定影响。  相似文献   

6.
GC-MS检测济南市东部空气中气相与颗粒物上有机污染物   总被引:2,自引:0,他引:2  
用GDX-101吸附剂和玻璃纤维滤膜(GF)同时采集气相和颗粒物上有机污染物,样品经提取分离后用GC-MS进行定性分析.结果表明,颗粒物上有机污染物的种类和含量都高于气相,工业区空气中有机污染较生活区严重,仍以燃煤、燃油污染为主.  相似文献   

7.
2015年10月15日—24日南宁市出现了一次典型的大气细颗粒物(PM2.5)污染过程,利用单颗粒气溶胶质谱仪和大气颗粒物激光雷达仪器进行监测,结合气象、后向轨迹及卫星遥感影像等资料分析大气污染成因及远距离传输对该次污染过程的影响。研究表明:此次南宁市大气污染以PM2.5超标为主,PM2.5日均质量浓度最高为85.2 μg/m3,超过标准值13.6%,其中PM1占PM2.5的66.3%。此次污染过程是由本地污染源与外来源影响互相叠加,在静稳、高温、强光等天气情况下发生协同作用引起的,污染物主要来源为燃煤源、机动车尾气源和生物质燃烧源,占全部来源的75.0%~80.0%。  相似文献   

8.
石家庄市大气颗粒物元素组分特征分析   总被引:2,自引:1,他引:1       下载免费PDF全文
为研究石家庄市大气颗粒物的污染特征及其来源,于2013年4—5月在主城6区分别采集TSP、PM10和PM2.5颗粒物样品,利用ICP-MS分析其中的22种元素浓度。结果表明,石家庄市城区Ca、Fe元素在各粒径颗粒物中含量都较高,PM2.5中的S、K含量较高,PM10和TSP中Mg、Al的浓度相对较高。颗粒物的主要来源为燃煤尘、道路尘和建筑尘,TSP、PM10和PM2.5具有较好的统计相关性和同源性。  相似文献   

9.
上海市浦东城区冬季颗粒物数浓度及其谱分布特征   总被引:6,自引:1,他引:5  
采用APS-3321空气动力学粒径谱仪对上海市浦东城区2012年12月至2013年2月0.5~20μm大气颗粒物浓度及其谱分布进行了实时监测。结果发现,上海市浦东城区冬季大气颗粒物数浓度为360个/cm3,其中0.5~1.0μm颗粒物数为345个/cm3,占总颗粒物的95.7%;1.0~2.5μm颗粒物数为15个/cm3,占颗粒物总数的4.1%;2.5~20.0μm颗粒物数为0.6个/cm3,占颗粒物总数的0.2%。当空气质量为AQI≤50、50AQI≤100、100AQI≤200、AQI200时,颗粒物数浓度分别为77.5、243.2、522.6、868.5个/m3。随着空气污染的加重,小于PM2.5颗粒物数浓度增加显著且对总的颗粒物数浓度的贡献也有所增加,且AQI200时,PM2.5中1.0~2.5μm颗粒物数浓度贡献增幅最大;此外,不同空气质量条件下,颗粒物数浓度的日变化存在一定差异,这对于空气污染防治具有重要意义。  相似文献   

10.
重庆城区不同粒径颗粒物元素组分研究及来源识别   总被引:2,自引:2,他引:0  
为研究重庆市大气颗粒物的污染特征及其来源,于2010年3—10月在主城区分别采集PM1.0、PM2.5和PM103种粒径的颗粒物样品,利用XRF分析其中的26种元素浓度。结果表明,重庆市主城区S元素在各粒径中含量都较高,细粒子中K的含量较高,粗粒子中Si、Ca和Fe的浓度较大。富集因子分析表明,主城区Cd、S、Se等污染元素的富集系数较大,且粒径越小,富集现象越明显。利用因子分析得出土壤风沙、扬尘、燃煤的燃烧、机动车燃油产生的尾气排放、生物质燃烧排放是重庆市颗粒物污染的主要来源。  相似文献   

11.
微波消解-原子吸收光度法测定土壤中铜锌铅镉镍铬   总被引:24,自引:5,他引:24       下载免费PDF全文
用微波消解-原子吸收光度法测定土壤中铜,锌,铅,镉,镍和铬。通过硝酸-氢氟酸-过氧化氢体系消解液对土壤样品消解,选择出微波最佳消解条件。对硝酸-盐酸-过氧化氢体系消解液和硝酸-氢氟酸-过氧化氢体系消解液进行消解对比试验,发现前者不能将土壤样品完全消解,后者能将样品消解完全,但需将消解液中剩余的酸赶尽,否则测定结果将明显偏低。微波消解土壤与传统电热消解相比,操作简便快速,可提高工作效率。  相似文献   

12.
The aim of the study was to determine the extent of heavy metal pollution in the vicinity of a lead battery manufacturing plant in the Czech Republic, both in the general environment and within homes. Topsoils (0–5 cm) were sampled from 100 sites along 4 transects which crossed the battery factory, the town centre and outlying rural areas. Housedust samples were collected from 15 plant-workers' homes and 15 non plant-workers' homes located at various distances from the factory. Samples were analysed for levels of Pb, Zn, Cd, Cu, As and Sb, using ICP-AES. Soil concentrations of Pb, Cd, As and Sb peaked at the perimeter fence of the battery factory with Pb levels of up to 12 650 g g> -1. Concentrations of these metals decreased exponentially within 500 m of the plant. Whilst the battery factory does appear to be a source of all the metals with the exception of Zn, emissions do not appear to be transported to any great extent over distances of more than 0.5 km. Topsoil and housedust concentrations of Pb, Zn, Cd, Cu, As and Sb in the general Mlada Boleslav area do not appear to be significantly different from those recorded in a large scale survey of urban soils in the United Kingdom. A comparison of housedust Pb concentrations in homes of plant workers and non-plant workers suggests that there may be a small input of Pb into the home environment by battery plant employees.  相似文献   

13.
Material Disposal Area G is the primary low-levelradioactive waste disposal site at Los Alamos NationalLaboratory, New Mexico, and is adjacent to Pueblo of SanIldefonso lands. Pueblo residents and Los Alamos scientists areconcerned about radiological doses resulting from uptake of AreaG radionuclides by mule deer (Odocoileus hemionus) andRocky Mountain elk (Cervus elaphus), then consumption ofdeer and elk meat by humans. Tissue samples were collected fromdeer and elk accidentally killed near Area G and were analyzedfor 3H, 90Sr, total U, 238Pu, 239, 240Pu,241Am, and 137Cs. These data were used to estimatehuman doses based on meat consumption of 23 kg y-1. Humandoses were also modeled using RESRAD, and dose rates to deer andelk were estimated with a screening model. Dose estimates tohumans from tissue consumption were 2.9 × 10-3 mSv y-1and 1.6 × 10-3 mSv y-1 from deer and elk, respectively,and RESRAD dose estimates were of the same order of magnitude. Estimated dose rates to deer and elk were 2.1 × 10-4 mGyd-1 and 4.7 × 10-4 mGy d-1, respectively. Allestimated doses were significantly less than established exposurelimits or guidelines.  相似文献   

14.
The San Francisco Estuary Regional Monitoring Program for Trace Substances (RMP) began in 1993 and is sponsored by 74 local, state, and federal agencies and companies through their discharge or Bay use permits. The RMP monitors water, sediment, toxicity, and bivalve bioaccumulation at 25 sites in the Bay that are considered to represent "background" conditions. Several major environmental issues have been identified by the RMP. Polychlorinated biphenyls and mercury were often above water quality guidelines, and often occurred in fish tissues above U.S. Environmental Protection Agency (U.S. EPA) screening values. Concentrations do not appear to be decreasing, suggesting continuing inputs. Episodes of aquatic toxicity often occurred following runoff events that transport contaminants into the Bay from urbanized and agricultural portions of the watershed. Sediment toxicity occurred throughout the Bay, and has been correlated with concentrations of specific contaminants (chlordanes, polynuclear aromatic hydrocarbons) at some locations; mixtures of contaminants were probably also important. Since the RMP does not monitor all ecosystem components, assessments of the overall condition of the Bay cannot be made. However, in terms of contamination, the RMP samples suggest that the South Bay, and North Bay sites are moderately contaminated.  相似文献   

15.
An important research area in life sciences is devoted to modeling, prediction, and dynamics of gene-expression patterns. As clearly understood in these days, this enterprise cannot become satisfactory without acknowledging the role of the environment. To a representation of past, present, and most likely future states, we also encounter measurement errors and uncertainties. This paper surveys and improves recent advances in understanding the foundations and interdisciplinary implications of the newly introduced gene–environment networks, and it integrates the important theme of carbon dioxide emission reduction into the networks and dynamics. We also introduce some operational and managerial issues of practical working and decision making, expressed in terms of sliding windows, quadrants (modules) of parametric effects, and navigating (controlling) between such effects and directing them. Given data from DNA microarray experiments and environmental records, we extract nonlinear ordinary differential equations that contain parameters that have to be determined. For this, we employ modern (Chebychevian) approximation and (generalized semi-infinite) optimization. After this is provided, time- discretized dynamical systems are studied. A combinatorial algorithm with polyhedra sequences allows to detect the region of parametric stability. Finally, we analyze the topological landscape of gene–environment networks with its structural (in)stability. By embedding as a module and investigating CO2 emission control and figuring out game theoretical aspects, we conclude. This pioneering work is theoretically elaborated, practically devoted to health care, medicine, education, living conditions, and environmental protection, and it invites the readers to future research.   相似文献   

16.
A migratory population of 78 pairs of Osprey (Pandion haliaetus) nesting along the Willamette River in westernOregon was studied in 1993. The study was designed to determinecontaminant concentrations in eggs, contaminant concentrationsin fish species predominant in the Ospreys diet, andBiomagnification Factors (BMFs) of contaminants from fish specieseaten to Osprey eggs. Ten Osprey eggs and 25 composite samplesof fish (3 species) were used to evaluate organochlorine (OC)pesticides, polychlorinated biphenyls (PCBs), polychlorinateddibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans(PCDFs). Mercury was also analyzed in fish. Geometric meanresidues in Osprey eggs were judged low, e.g., DDE 2.3 g g-1 wet weight (ww), PCBs 0.69 g g-1, 2,3,7,8-TCDD 2.3 ng kg-1, and generally well below known threshold values for adverse effects on productivity, and the population was increasing. Osprey egg residue data presentedby River Mile (RM) are discussed, e.g., higher PCDDs were generally found immediately downstream of paper mills and eggsfrom the Willamette River had significantly elevated PCBs and PCDDs compared to reference eggs collected nearby in the CascadeMountains. Prey remains at nest sites indicated that the Largescale Sucker (Catostomus macrocheilus) and NorthernPikeminnow (Ptychocheilus oregonensis) accounted for an estimated 90.1% of the biomass in the Osprey diet, and composite samples of these two species were collected from different sampling sites throughout the study area for contaminant analyses. With the large percentage of the fishbiomass in the Osprey diet sampled for contaminants (and fisheaten by Ospreys similar in size to those chemically analyzed),and fish contaminant concentrations weighted by biomass intake, a mean BMF was estimated from fish to Osprey eggs for the largeseries of contaminants. BMFs ranged from no biomagnification(0.42) for 2,3,7,8-TCDF to 174 for OCDD. Our findings for themigratory Osprey were compared to BMFs for the resident HerringGull (Larus argentatus), and differences are discussed. Webelieve a BMF approach provides some basic understanding ofrelationships between contaminant burdens in prey species offish-eating birds and contaminants incorporated into their eggs,and may prove useful in understanding sources of contaminants inmigratory species although additional studies are needed.  相似文献   

17.
The draft of the German guideline to calculate automobile exhaust dispersion is explained. It contains a two-stage-system: For first quick estimates the guideline contains the simple models MLuS and STREET. In case these models are not applicable or their results shows concentration levels close to the air quality standards, the more complex models PROKAS_V and MISKAM are recommended. PROKAS_V is a Gaussian plume model, MISKAM is a 3-dimensional microscale non hydrostatic flow model for built-up areas with an Eulerian dispersion model. The guideline comprises cases in rural areas without or with few adjacent buildings as well as urban areas with buildings near the roads. The contribution gives information about the models, typical results and some of the problems showing up presently.  相似文献   

18.
This paper gives mathematical details and sample applications of SWAGMAN Farm (SWAGMAN, Salt Water and Groundwater Management), a farm-scale hydrologic economic model that integrates agronomic, climatic, irrigation, hydrogeological and economic aspects of irrigated agriculture. The model is capable of determining optimum mix of land use to keep watertable and soil salinity within acceptable limits while maximising the economic returns. Alternatively, the model can simulate water and salt balance and economics of a given cropping preference. Web-based and Geographic Information Systems versions of the model are available for integration with the environmental reporting systems of the irrigation areas.  相似文献   

19.
The population counts of hydrocarbon-utilising yeasts weremonitored at six sampling stations in the Benin City municipalarea over a four-week period. Although the population countswere relatively constant in each locality, the highest countsoccurred in areas heavily polluted by domestic and industrialeffluents. A total of thirty-five hydrocarbon-degrading yeastswere isolated from soil at the sampling stations usingn-hexadecane as sole carbon source. The isolates were identifiedas belonging to the genera Candida (27 strains), Endomycopsis (4 strains). All the organisms grew on long-chainn-alkane, kerosene, diesel oil and crude oil but failed to growon short-chain n-alkane, aromatic and alicyclic hydrocarbons.Measurement of growth attributes of the isolates usingn-hexadecane, diesel oil and crude oil as substrates showed thatthe Candida species were better utilizers of hydrocarbonsubstrates relative to Endomycopsis and Schizosaccharomyces species.  相似文献   

20.
用火焰原子吸收光谱法测定了苏州开发区26种蔬菜中的铜、锌、铁、锰和镍的含量。蔬菜样品用硝酸高氯酸混合酸进行消解。4次测定值的相对标准差<5%,加标回收率在92%~107%之间。26种蔬菜中铜、锌、铁、锰、镍的含量基本均在世贸组织规定的范围内。  相似文献   

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