铅锌冶炼厂周边土壤铅源的铅同位素示踪

以某铅锌冶炼厂周边土壤为研究对象,通过对其原料及周边土壤中铅含量的检测,结果显示：该冶炼厂周边土壤铅质量比在22.73mg/kg～126.51mg/kg之间,平均值为42.68mg/kg,是当地土壤铅背景值的1.85倍.采用铅质量比空间分布分析和同位素混合模型计算分析了冶炼厂周边土壤中铅的可能来源,分析表明：土壤铅质量比的空间分布及铅同位素比值与冶炼厂的焦化原料煤相近,焦化原料煤对周边土壤铅污染贡献最大.     

拉鲁湿地芦苇不同部位金属元素富集规律研究

通过在拉鲁湿地布设7个采样点,采集湿地植物芦苇,检测分析K、Na、Ca、Mg、Cu等23种元素在其根、茎、叶、花中的分布特征。结果表明,同一元素在芦苇不同部位及同一部位不同元素的含量、转移能力、富集能力等均差异较大。元素平均质量比范围为0.055 mg/kg(Tl)～2.20×10~4 mg/kg(Na),大部分元素在芦苇不同部位的分布符合根花叶茎这一规律;芦苇对Ca转移能力最强,对Fe的转移能力最弱;芦苇对Fe富集能力最强,特别是根部对Fe的富集系数高达506万倍。     

废弃矿山生态复绿常用17种植物叶绿素含量及SOD和POD活力测定

选用废弃矿山绿化常用的禾本科、豆科、葡萄科和紫葳科共17种为实验材料,测定了其叶绿素各组分含量及超氧岐化酶(SOD)和过氧化物酶(POD)活力,结果表明:叶绿素a、b类胡萝卜素和叶片色素总质量比最高的植物分别是胡枝子、狗牙根、牧草型狗牙根和狗牙根,其质量比分别为2.46 mg/g.FW、1.10 mg/g.FW、0.32 mg/g.FW和3.63 mg/g.FW;4者质量比最低的是紫穗槐、三出叶爬山虎、芒和紫穗槐,为1.10 mg/g.FW、0.48 mg/g.FW、0.08 mg/g.FW和1.70 mg/g.FW。ωa(叶绿素a)/ωb(叶绿素b)最高的是牧草型狗牙根,为3.03 mg/g.FW,最低的是芒,仅为1.65 mg/g.FW。POD和SOD活力最高的是网络崖豆藤和芒,达477.00 U和217.20 U,最低的是牧草型狗牙根和紫穗槐,仅为24 U和39.43 U。     

电感耦合等离子体质谱法测定海产品中铅及其同位素比值

采用微波消解,电感耦合等离子体质谱法测定海产品中铅含量及其同位素比。通过选择本底铅浓度低的硝酸降低背景值,选择合适内标以减少仪器波动带来的误差,使得该方法在0μg/L~100μg/L范围内线性良好,~(204)Pb、~(206)Pb、~(207)Pb和208Pb的方法检出限为0.041μg/L~0.180μg/L。用该方法测定有证标准物质,结果在标准值范围内,海产品样品6次测定结果的RSD为3.1%~8.6%,加标回收率为89.9%~96.3%。26种海产品中总铅质量比为0.018 mg/kg~2.32 mg/kg,铅同位素~(207)Pb/~(206)Pb值为0.783 55~0.881 61。     

霞湾港沉积物铅形态及垂直分布特征

采用Tessier五步浸提法对湘江霞湾港的沉积物垂直样品进行处理,分别提取可交换态、碳酸盐结合态、铁锰氧化物结合态、有机结合态和残渣态5种形态的铅,并采用电感耦合等离子体发射光谱法(ICP-AES)测定其含量。结果表明,位于霞湾港下游的采样点2的铅污染较严重。3个采样点位沉积物中的铅总质量比为116.52 mg/kg~262.85 mg/kg,不同深度沉积物中铅主要以铁锰氧化物态和残渣态存在,其比例为60.5%~87.0%,而可被生物吸收利用的有效态(碳酸盐结合态和可交换态)铅占比相对较低,仅为2.8%~11.1%。     

西安市表层土壤中邻苯二甲酸酯(PAEs)含量与构成

通过在西安市三环内6个功能区布设62个采样点,采样分析其表层土壤中邻苯二甲酸酯(PAEs)质量比及其构成特征。结果表明,西安市表层土壤中DMP、DEP、BBP、DnBP、DEHP和DnOP平均值分别为0.188 mg/kg、0.187 mg/kg、0.091 mg/kg、4.174 mg/kg、6.122 mg/kg和0.188 mg/kg,6种PAEs总质量比(∑6PAEs)范围为1.54 mg/kg^153.17 mg/kg,平均值为10.95 mg/kg。6个功能区∑6PAEs从高到低为交通区>工业区>混合区>公园>文教区>住宅区。与其他城市表层土壤中PAEs值比较发现,DMP处于高水平,DEP、DnBP、DEHP和∑6 PAEs处于较高水平,BBP和DnOP处于中等水平。     

三峡库区柑橘对土壤重金属吸收富集特征研究

研究区域柑橘果实重金属含量符合NY/T 426-2000<绿色食品柑橘>标准,果实品质达到一级产品.土壤中重金属的含量越高,柑橘叶片、果皮、果肉的重金属含量也越高.柑橘叶片对土壤重金属铜、锌、铅、镉、镍、汞、砷、铬的吸收富集能力显著大于果皮与果肉,果皮对土壤重金属铜、锌、铅、镉、汞的吸收富集能力显著大于果肉,果肉对土壤重金属铬的吸收富集能力显著大于果皮.柑橘同一部位对土壤中不同重金属元素的吸收富集能力也存在很大的差异,柑橘叶片对土壤中不同重金属元素的富集系数大小顺序为Hg＞Pb＞Cd＞Cu＞Zn＞Cr＞As＞Ni,柑橘果皮对土壤中不同重金属元素的富集系数大小顺序为Cd＞Hg＞Cu＞Zn＞Pb＞Cr＞Ni＞As,柑橘果肉对土壤中不同重金属元素的富集系数大小顺序为Hg＞Cu＞Cr＞Zn＞Cd＞Ni＞Pb＞As.     

道路绿化带影响大气颗粒物分布实测研究

以福州市西三环快速路某路段为实验靶区，利用微型环境检测仪采集路边细颗粒物(PM_2.5)、亚微米颗粒物(PM_1.0)和黑碳(BC)的空间分布样本，解析其在道路绿化带前后(绿化带前是指干道和辅道外边缘线位置，其他位置均视为绿化带后)的变化特征及原因。结果表明：(1)颗粒物浓度随着采样点远离干道而整体趋于递减，呈现BC>PM_2.5>PM_1.0的衰减率变化特征，且植被稠密的路边环境对应更大的颗粒物浓度降幅。(2)夏季绿化带后的颗粒物浓度降幅高于冬季，冬季绿化带后部分采样点的PM_1.0和PM_2.5浓度甚至有所抬升。在植被茂密的路边环境下，风自干道吹向绿化带情景的路边空气质量介于风自绿化带吹向干道情景和风平行于干道情景之间。(3)BC对交通变化的敏感性高于PM_2.5和PM_1.0,植被茂密的绿化带后的颗粒物浓度降幅会因交通强度的上升而增大。风自干道吹向绿化带时，绿化带对颗粒物的调节作用会随交通源强和季节的变化而不同...     

羊八井地热区典型植物对氟的吸附富集特征探究

采用水浴提取法处理羊八井地热区土壤和植物样品中可溶性氟，并用离子选择性电极法测定提取液及地热水中的氟。结果表明，地热水中氟离子最高为162 mg/L，土壤和植物中水溶性氟分别为347 mg/kg~937 mg/kg和189 mg/kg~164 mg/kg。氟离子在不同植物中的分布差异较大，嵩草属植物富集氟离子的能力最强，故可利用植物修复技术对高氟地热水、土壤净化处理，以降低氟污染。     

兰州西固区土壤中有机氯农药污染特征及风险评价

采集兰州西固区土壤样品,采用GC/μECD方法检测样品中有机氯农药(OCPs)污染残留,并分析调查区土壤中OCPs污染特征、来源及潜在生态风险。结果表明,8种OCPs异构体在兰州西固区土壤中的检出率均为100%,总质量比范围在18.34μg/kg~125.34μg/kg之间,平均值为54.84μg/kg;土壤中BCHs和DDTs残留质量比分别为0.742μg/kg~29.3μg/kg和10.9μg/kg~98.6μg/kg。OCPs残留以p,p'-DDT和β-BCH为主。不同采样点土壤样品中OCPs的残留量从高到低依次为路边样绿化带样树根土样菜地样。对DDTs与BCHs异构体残留组分分析发现,调查区土壤中残留的BCHs主要源于历史应用,而DDTs源于近期污染。     

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。     

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.     

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.     

实验室质量管理体系内部审核的实施

在实施GB/T15481-2000 idt ISO/IEC17025:1999标准《检测和校准实验室能力的通用要求》的过程中,通过实验室质量管理体系内部审核的实践与系统分析,识别出内部审核实施阶段的关键环节,提出召开首次会议、收集审核证据、确定审核发现和召开末次会议的技术方法,对提高内部审核的质量和有效性、获得可靠的审核结论具有重要意义。     

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.