大气总悬浮微粒中某些元素的火焰原子吸收分光光度测定法

采用外加百叶箱的国产KB-250空气采样泵,用直径12.5cm国产过氯乙烯滤膜收集20小时大气总悬浮微粒样品,样品滤膜在450℃灰化后用氢氟酸和硝酸硝化、溶解,并用火焰原子吸收法测定其中的K、Na、Ca、Mg、Fe、Zn、Mn、Co、Cu、Ni、Cd、Cr、Pb13种元素。结果表明,该法采集的样品滤膜均匀,前处理方法简便,回收率、精密度均符合要求。     

上海浦东新区环境空气重金属污染特征及来源解析

于2012年3月—2013年2月在浦东新区城区点和郊区点采集TSP样品,利用双酸消解原子荧光法、ICP法分析了样品中的13种元素。结果表明,除As略超标外其他元素均达标,城区点和郊区点环境空气重金属年均值排在前3位的元素是:Fe、Sn、Zn,占样品金属总量的83%~87%;排在末4位的元素是:Ni、Cr、As、Cd,占金属总量的1%~2%。通过EPA PMF 5.0模型运算结果,在城区中6个因子贡献比最高的31.5%为Sn+Fe+Mn,贡献比最低的2.1%为Hg;在郊区中6个因子贡献比最高的36.4%为Pb+Cu,贡献比最低的9.2%为Fe+Sn+Mn。浦东新区富集因子E≤10的元素有Cr、V、Ba、Mn、Ni、Fe、Hg城、Cu郊、As;富集因子E10的元素有Hg郊、Cu城、Zn、Pb、Cd、Sn。     

在线ICP-MS检测地表水中19种元素

建立了基于电感耦合等离子体质谱法(ICP-MS)在线检测地表水中19种元素(Be、B、Ti、V、Cr、Mn、Co、Ni、Cu、Zn、As、Se、Mo、Ag、Cd、Sb、Ba、Tl和Pb)的分析方法,并对吴江某河流水中这些元素的含量进行实时在线检测。结果表明,19种元素检出限为0.001~0.410μg/L,加标回收率为92.0%~106%,精密度为1.0%~4.70%;该法与实验室检测结果的相对偏差为1.2%~5.6%,检测结果一致性良好;连续20 d在线检测水中Sb含量与实验室检测结果和浓度变化趋势基本一致。该方法可用于地表水中19种元素含量的实时、快速、连续监测。     

南京市大气PM2.5中重金属分布特征及化学形态分析

于2017年1、4、7、10月在南京市主城区采集了大气PM2.5样品,用BCR法对PM_(2.5)中重金属进行连续提取,采用电感耦合等离子体-质谱法进行测定,分析重金属在颗粒物中不同形态和分布特征。结果表明,PM_(2.5)中9种重金属质量比排序为:Fe Zn Pb Mn Cu Cr As Ni Cd。Zn、Pb、Cd、Cu、Mn、As主要分布在弱酸提取态; Ni在弱酸提取态、可氧化态和残渣态中分布较均匀,占比26%～37%;而Fe、Cr主要以残渣态存在,分布比例分别为71%和54%。PM_(2.5)中Zn的生物有效性系数 0.8,属生物可利用性元素,表明其在环境中迁移能力最强,其余8种重金属生物有效性系数为0.2～0.8。     

抚顺市PM10中元素分布特征及来源分析

为了确定抚顺市PM10中元素的浓度特征及其来源,于2006—2007年的采暖季、风沙季和非采暖季在抚顺市的6个采样点采集PM10样品,并用等离子体原子发射光谱法(ICP-AES)测定样品中Ti、Al、Mn、Mg、Ca、Na、K、Cu、Zn、As、Pb、Cr、Ni、Co、Cd、Fe、V等17种元素的含量。结果表明,Al、Mg、Ca、Na、K、Mn、Fe等地壳元素在17种元素中占有较大比重,全年平均达到97.0%。富集因子分析结果表明,Cu、Zn、Pb、Cr、Co、Cd等元素在各季和各采样点明显受到人为活动影响,是典型的污染元素。主因子分析结果显示,土壤风沙尘、建筑尘、燃煤尘、道路扬尘、机动车尾气排放、金属冶炼、锰、铜、钛工业源是抚顺市PM10中元素的主要来源。     

鞍山市大气尘和金属元素沉降通量及污染特征

通过采集鞍山市11个点位的降尘样品以及土壤样品,用ICP-MS分析了Cu、Mn、Zn、Pb等元素含量,并计算其沉降通量。结果表明,鞍山地区大气降尘的沉降通量为2.92～59.8g/(m2.month),其中鞍钢厂区沉降通量均值为31.6g/(m2.month),分别是周边地区和对照地区的4.72倍和10.5倍。重金属As、Cr、Pb和Cd的沉降通量分别为3.78、45.5、42.8、0.457g/(hm2.month)。降尘中各元素的富集系数为0.29～190,其中Cu、Fe、Zn、Mo、Cd、Pb和Se的富集系数大于10,说明这些元素主要来自于人为源。鞍钢厂区土壤中Cu、Pb、Mn、Zn、Mo、Cd、Ca、Fe和Se的含量较辽宁省土壤背景值高,说明其土壤环境已经受到了人类活动的影响。     

典型金属冶炼城市降尘中重金属污染特征及风险评价

2021年1-3月,采集湖南省某典型金属冶炼城市不同功能区的降尘样品,分析测定了17种重金属元素含量,其中15种重金属元素含量超出了湖南背景值,分别为Ag、Fe、Cd、Ti、Sb、Tl、Pb、As、Zn、Cu、Mo、Ni、Cr、Ba、Mn。采用地累积指数法、潜在生态危害指数法和健康风险评价模型对大气降尘中重金属可能造成的生态风险和健康风险进行评价。结果表明:受长期的有色金属冶炼影响,Ag、Cd、Fe、Sb、Ti、Tl 6种重金属达到了极重度污染,Pb、As、Zn、Cu、Mo在中度污染程度以上。工业区的综合生态危害指数远高于工业居民混合区、工业农业混合区、居民区和交通区,达到了极强生态危害级别。健康风险评价结果显示:大气降尘中As和Pb存在非致癌风险,As、Cd和Ni存在致癌风险,且经口摄入是最主要的暴露途径。与青少年和儿童相比,大气降尘中重金属对成人造成的风险较高,且成年女性面临的风险高于成年男性。     

新疆焉耆县耕地土壤重金属的空间分布及来源解析

在新疆焉耆县采集53个耕地土壤样品,测定其中As、Cd、Cr、Cu、Mn、Ni、Pb和Zn的质量比,基于GIS技术研究其空间分布格局,运用多元统计分析法区分其主要来源。结果表明:焉耆县耕地土壤中Cd、Cr、Ni、Pb和Zn的质量比平均值分别超过新疆灌耕土背景值的0.50、0.40、0.33、1.63和3.92倍;在研究区内As、Cd、Pb质量比呈现由北向南逐渐升高趋势,Cr、Cu、Zn质量比呈现由北向南降低趋势,Mn和Ni质量比出现西部高值区;耕地土壤中As、Cd、Ni和Pb的来源主要受人类活动的影响,Cu和Mn的来源主要受土壤地球化学作用的控制,Cr和Zn的来源可能受人为污染与自然因素共同控制。     

北京灰霾天气PM10中微量元素的分布特征

采用电感耦合等离子体质谱法(ICP-MS)对北京市2008年4月和5月不同采样点采集的灰霾天PM₁₀样品中的15种微量元素进行了分析,得出了Ti、Fe、Zn、Sn、Pb为全样样品中相对含量较高元素;Ti、Mn、Ni、Cu、Zn、Pb是水溶样样品中相对含量较高元素。与晴天相比,灰霾天样品中微量元素可溶性增强,对人体危害更严重。与2002年分析数据进行对比,因2002年缺少Cr、Cd元素的测试值,全样样品中除了Co、Ni、Cu、Mo元素外,其余测试元素的浓度均有不同程度的升高,Fe和Sn元素的增幅最大。水溶样品中,参与对比元素的含量均下降。文中对含量相对较高的Cr、Mn、Fe、Cu、Zn、Cd、Sn和Pb元素进行了源解析,分析得出采样点附近的交通源及地面扬尘是这些元素的主要来源。     

高频电感耦合等离子体发射光谱法测定污水中10种元素

试验了高频电感耦合等离子体发射光谱法同时测定污水中Fe、Zn、Cu、Mn、Pb、Cd、As、Ca、Cr和Al等10种低含量元素的方法。方法的检测限能满足污水的测定要求,并具有较好的稳定性。10种元素的相对标准差均<5%,回收率在93%～101%之间。     

锅炉烟尘测试中锅炉负荷率的计算方法探讨

GB5468 -91规定 ,锅炉烟尘测试时 ,必须对锅炉的运行负荷进行测试 ,而实际监测过程中 ,许多锅炉房不具备测试的计量条件 ,为了解决这一问题 ,文章提出利用烟气量和空气过剩系数计算锅炉负荷率。在实际监测工作中 ,该方法方便、易于操作 ,所得结果和标准规定方法所得结果有很好的一致性     

城市空气质量周报效用分析

介绍了世界上一些发达国家的空气污染预报的做法和采取的措施,阐述了我国开展空气质量预报的方针和方法,指出了周报是预报的基础工作。叙述了我国空气质量周报的污染参数的选取、污染指数的分级及其浓度限值和污染指数计算及确定,分析并总结了开展城市空气质量周报所发挥的效用是提高公众的环保意识,加大了治理污染的力度,转变了环境监测的职能,促进了环境监测事业的发展     

水中总硬度测量不确定度的评定

采用EDTA滴定法测定水质总硬度的测量不确定度评定。充分考虑测量重复性、标准溶液的配制、滴定等过程对测量的影响,计算水中总硬度的测量相对合成标准不确定度为1·81×10-3。     

贵州黔东南州三板溪水库春季拟多甲藻水华特征

2011年3月13日对贵州省黔东南州三板溪水库进行春季浮游植物调查的结果表明,三板溪水库Ⅱ号采样点(下革东)发生以佩纳形拟多甲藻为优势种的拟多甲藻水华,细胞密度高达1.15×10⁷cell/L;板溪水库总氮的最低值为2.09 mg/L,总磷的最低值为0.95 mg/L,三板溪水库的总氮、总磷含量较丰富,不存在总氮或总磷是限制性因子;通过SPSS16.0统计软件分别进行Pearson 积距相关系数分析表明,氮磷比是三板溪水库发生拟多甲藻水华的主要影响原因。     

Fractionation of heavy metals and assessment of contamination of the sediments of Lake Titicaca

Chemical weathering is one of the major geochemical processes that control the mobilization of heavy metals. The present study provides the first report on heavy metal fractionation in sediments (8–156 m) of Lake Titicaca (3,820 m a.s.l.), which is shared by the Republic of Peru and the Plurinational State of Bolivia. Both contents of total Cu, Fe, Ni, Co, Mn, Cd, Pb, and Zn and also the fractionation of these heavy metals associated with four different fractions have been determined following the BCR scheme. The principal component analysis suggests that Co, Ni, and Cd can be attributed to natural sources related to the mineralized geological formations. Moreover, the sources of Cu, Fe, and Mn are effluents and wastes generated from mining activities, while Pb and Zn also suggest that their common source is associated to mining activities. According to the Risk Assessment Code, there is a moderate to high risk related to Zn, Pb, Cd, Mn, Co, and Ni mobilization and/or remobilization from the bottom sediment to the water column. Furthermore, the Geoaccumulation Index and the Enrichment Factor reveal that Zn, Pb, and Cd are enriched in the sediments. The results suggest that the effluents from various traditional mining waste sites in both countries are the main source of heavy metal contamination in the sediments of Lake Titicaca.     

Environmental Assessment of the Impact of Ozone to the Neuston of the Sea-Surface Microlayer of the Gulf of Mexico

Substantial amounts of NOx (146 000 t/y) and total hydrocarbons (294 000 t/y) are released to the marine atmosphere by the large number of oil and gas operations over Federal waters of the Gulf of Mexico (GOM). Under appropriate meteorological conditions these emissions react to form ozone (0–54 g/m3 over-water) which can affect the marine environment. Using a dry deposition model, this work examines the amount of ozone derived from oil and gas offshore operations and deposited in the sea surface of the Gulf of Mexico, and assesses its impact on the neuston of the sea-surface microlayer. Surface integrated estimates of ozone deposited from oil and gas operations over the sea surface ranges from 400 kg to 1800 kg which results in sea surface concentrations of 15 g/m3. This estimate and the actual toxic ozone levels suggest no acute, toxic impacts to the neuston. However, indirect effects may occur through changes to the pelagic foodwebs and organic carbon pathways. Another potential pathway for ozone impacting the environment is through the production of bromate. Based on the concentrations and time scales (11–139 days) only sublethal effects appear to occur, but uncertainties associated with this assessment need to be further studied. From an ecological perspective, the environmental impacts and risks of NOx and VOC discharges from offshore platforms need to be assessed for neuston and other components of the marine ecosystem.     

二乙氨基二硫代甲酸银试剂质量对测砷的影响

用简单合成了二乙氨基二硫代甲酸银试剂，并比较了自制和市售的二乙氨基二硫人 银对测砷的影响。结果表明，采用自制的二乙氨基二硫代甲酸银能大大降低试剂空白，提高方法的灵敏度和降低检出限，试剂质量明显优于市售产品。     

氨氮测量不确定度的评定

采用纳氏试剂光度法测定水质氨氮的测量不确定度评定,应该考虑工作曲线、测量重复性、标准溶液、仪器读数分辨率等对测量的影响.     

Evaluation of method of preparation of passive diffusion tubes for measurement of ambient nitrogen dioxide

This study was carried out in response to suggestions that the measurement of NO(2) by Palmes-type passive diffusion tubes (PDT) is affected by the method of preparation of the triethanolamine (TEA) absorbent coating on the grids. The following combinations of factors were investigated: TEA solvent (acetone or water), volume composition of TEA in solvent (50% or 20%), and grid coating method (dipping in solution prior to assembly or pipetting solution on after assembly). Duplicate PDTs prepared by each of the 8 methods were exposed in parallel, in urban air, for a total of 80 separate 1 week exposures. NO(2) concentrations derived from PDTs prepared by pipetting methods were significantly less precise than concentrations from dipping methods, with mean RSDs for duplicate measurements of 13.8% and 8.5%, respectively (n= 316 each category). Pipetting methods using solutions of 50% TEA composition were particularly imprecise (mean RSD 17.2%). Data from PDTs prepared by pipetting methods were systematically more poorly correlated with each other and with data from co-located chemiluminescence analysers, than corresponding data from PDTs prepared by dipping methods, indicating that more consistent accuracy was also obtained by the latter PDTs. The statistical evidence suggested that PDTs prepared by pipetting 50% TEA in water generally gave lower NO(2) concentrations. Although this is in agreement with a previous study, it is also possible that such an observation here may be a statistical artefact given the demonstrably poorer precision of this method. The general tendency of PDTs to show positive bias in NO(2) measurement in urban air in 1 week exposures was again evident in this study (mean biases at roadside and urban centre locations of +35% (n= 475) and +18% (n= 112), respectively) consistent with augmentation of within-tube NO(2) flux by chemical reaction between co-diffusing NO and O(3). Overall, it is recommended that the pipetting method of PDT grid preparation is avoided, or at least investigated further, because of the apparent degradation in precision and accuracy of NO(2) measurement. Potential reasons for the effect are discussed.     

污染物总量控制中载体水流量的测定

示踪剂法测定河水流量是较为准确的办法 ,利用河流动力模型计算出示踪剂投放点 ,利用示踪剂投放量与测定浓度之间的关系可方便地获得河水流量结果