ICP-MS法测定地下水中痕量元素的条件选择

采用氦气碰撞模式和内标法抑制ICP-MS测试地下水中痕量元素的多原子离子干扰和基体效应。探讨He流量、内标元素、宏量离子等因素对测定的影响,结果表明:187Re、208Pb响应值与He流量呈线性下降模型,其他离子为指数下降模型,He流量为2. 5 m L/min～3. 0 m L/min时满足地下水质量分级测定要求;内标元素的响应因子随质量浓度的增大而降低,16. 0μg/L以上时趋于稳定;酸度显著影响测定误差,选用较大质量数的内标元素和保持样品酸度的一致可提高测定的准确度。     

土壤中14个元素的X射线荧光分析

本文使用日本理学3070型全自动X射线荧光光谱仪,以硼酸镶边垫底的粉末直接压片制样法,用国家级土壤和水系沉积物标样做为标准样品选定测定条件,通过回归方法求取各元素的工作曲线常数,用经验系数法校正元素间效应,对某些痕量元素间的效应用散射线内标法进行校正,估算出各元素的理论检出限。经过试验,本法能成功地确定土壤背景值调查研究中选择项目的Al、Ba、Ca、Fe、Ga、K、Mg、Na、Nb,Rb、Sr、Ti、Y和Zr等元素的含量。     

ICP-MS法测定水稻田表层土壤中重金属元素Zn、Cd、Pb、Cu、Cr、Mn的研究

报道了用ICP-MS法直接测定水稻田表层土壤中的重金属元素Zn、Cd、Pb、Cu、Cr、Mn含量的方法.土壤样品经HNO3-HF-HClO4彻底消化后,加入内标元素45Sc、115In、204Tl,采用内标法进行测定,有效地克服了基体效应、接口效应及仪器波动所产生的影响;通过优化仪器的工作参数,选择待测元素适当地测定同位素,有效克服了因质谱干扰所带来的影响.对污染土壤标准物质(编号GBW08305)进行测定,测定结果与标准值相吻合.该方法的加标回收率是98.0%～102.0%,相对标准偏差是2.2%～3.5%,具有线性范围宽、简单、快速、准确等特点.     

电感耦合等离子体质谱法测定尘土样品中贵金属元素的研究

建立了用电感耦合等离子体质谱法(ICP-MS)测定尘土样品中贵金属元素Au、Pt、Pd、Ir、Ru、Rh的方法.样品用王水微波消解后,试液直接用ICP-MS同时测定上述6种贵金属元素.以Sc、Y、In作为内标物质,补偿了基体效应;选择适当的待测元素同位素克服了质谱干扰;确定了最佳测定条件.结果表明,6种贵金属元素的检出限为0.004～0.006 μg/L,线性关系良好,相关系数r≥0.999 2,回收率为83%～97%,RSD＜3.6%.该法准确、快速、简便,已成功地应用于尘土样品中微量贵金属元素的测定.     

电感耦合等离子体法(ICP-MS)测定地表水12种稀土元素

建立电感耦合等离子体质谱法(ICP-MS)测定地表水中镨、钕、钐、铕、钆、铽、镝、钬、铒、铥、镱、镥12种稀土元素的方法。地表水样品通过0.45μm滤膜过滤后,试液直接用ICP-MS同时测定上述12种重金属元素。以铑和铼作为内标物质,校正响应信号的变化,消除基体效应;选择适当的待测元素同位素克服了质谱干扰;确定了最佳测定条件。结果表明,12种稀土元素的检出限为0.01～0.02μg/L;相关系数r0.999 0;实际样品加标回收率为91.5%～106%;相对标准偏差为0.26%～1.09%。该方法简便、快速、准确,可应用于地表水中微量重金属元素的测定。     

偏振能量色散X-射线荧光光谱法测定土壤中Ni、Cu、Zn、Pb四种重金属元素

以土壤和水系沉积物标准物质为校准样品,采用粉末样品压片制样,建立了偏振能量色散X-射线荧光光谱仪测定土壤中Ni、Cu、Zn、Pb四种重金属元素的方法。该方法分别采用Ge,Zn,Zr等3个不同二次靶对被分析元素进行选择性激发和测定,利用经验系数和康普顿散射线作内标校正基体效应,优化了元素校准曲线方程,实验结果表明,土壤和水系沉积物标准物质准确度实验结果符合定值要求,方法精密度RSD在1.12%~6.09%之间(n=10),Ni、Cu、Zn、Pb四种重金属元素的检出限分别达到2.54、0.93、0.96、0.98 mg/kg。土壤样品测定值与原子吸收法测定结果一致,该方法准确度、精密度、检出限均能满足土壤检测的需要。     

微波消解-ICP-MS测定土壤和底泥中的12种金属元素

以20.0μg/L铟作内标,采用硝酸-氢氟酸-过氧化氢体系微波消解,ICP-MS(电感耦合等离子体质谱法)同时测定土壤和底泥中的12种金属元素,各元素方法检出限为0.003～0.2μg/g,相对标准偏差小于6.1%,土壤标准样品的测定值与标准值吻合。方法简便快捷,灵敏度高,重现性好,是分析大批量土壤和底泥样品中多元素的可靠、高效方法。     

微波消解ICP-MS法测定宣威和富源土壤中的微量元素

建立了微波消解-ICP-MS法测定土壤中32种微量元素的方法。采用氢氟酸-硝酸-过氧化氢体系微波消解,稀释定容后用ICP-MS对溶液进行元素的测定,在优化仪器工作参数后,以双内标铑(Rh)和铼(Re)进行校正。元素检出限为0.01～0.45ng/ml,测定国家标准物质西藏土壤成分分析标准物质GBW 08302中的元素,测定值与标准值或参考值基本一致,用该法测定云南宣威和富源两地24份土壤样品结果表明,该方法快速、简便、准确,适于土壤中多种微量元素的测定。     

高盐榨菜生产废水中化学需氧量的测定方法探讨

针对高盐榨菜生产废水中氯离子对CODcr测定的干扰问题,研究了完全氧化—差减法,运用该法对高盐标样和实际样品进行测定,准确度高、精密度好,适合于高盐榨菜生产废水CODcr的测定。     

水中苯胺类化合物分析的难点

结合实验研究了水中苯胺类化合物的测定难点和影响因素，包括样品保存和水样中悬浮物的影响。苯胺类化合物易被氧化，样品不易保存且受悬浮物的影响。研究结果表明：样品中未加入抗氧化剂进行保存时，部分苯胺类化合物迅速降解；当样品中加入80 mg/L硫代硫酸钠进行保存时，部分苯胺类化合物的保存时间可以延迟2~3 d后降解。样品中悬浮物对联苯胺萃取影响较大，回收率偏低，可以通过调节样品pH至酸性后过滤，再将滤液调至中性后进行萃取，回收率明显提高。笔者同时讨论了消除与补偿基质干扰的方法，包括色谱分离条件和检测器条件的选择、优化，内标法、空白基质匹配标准校正法和工作曲线法等定量方法的选择。     

滤膜在颗粒物无机元素监测中的适用性研究

筛选国内外12个制造商的玻璃纤维、石英、特氟龙、聚丙烯、乙酸纤维、硝酸纤维和混合纤维等7类材质34种滤膜,测定滤膜中的铍、铬、锰、钴、镍、铜、锌、砷、钼、镉、锡、锑、铊和铅等14种元素含量,探讨不同材质滤膜中各元素的质量分数分布,采用大气固定源污染物排放标准中项目限值和分析方法标准中质量控制要求,对铜、锌之外的12种元素进行适用性评价。结果表明:玻璃纤维滤膜比其他材质滤膜中无机元素的质量分数高1～5个数量级,进口玻璃纤维滤膜中铬、镍、砷、镉等4种元素质量分数高于多数国产玻璃纤维滤膜,国产A、H玻璃纤维滤膜中14种元素质量分数相对较低;仅混合纤维滤膜中镉、铅的测定值浓度低于最严标准限值的10%,玻璃纤维滤膜之外的其他材质滤膜均能满足监测其余10种元素的本底需求。     

土壤重金属分析方法间检测结果一致性判断方法——数据对t值检验法的改进与完善

不同分析方法测定结果间的比较,或者说如何判断两种分析方法测定结果的一致性,是检测实验室经常遇到的实际问题。其应用场景包括方法标准验证实验、新方法与经典方法间的比对,特别是在缺少标准样品、测试数据不满足t值检验的条件下,选用合适的判据尤其重要。以采用单波长激发型能量色散X射线荧光光谱法、电感耦合等离子体质谱法、波长色散X射线荧光光谱法测定土壤和水系沉积物样品中Cd、As、Pb、Cu、Zn、Ni、Cr、Co、V、Mn、Mo、Sb等重金属含量所得数据为例,探讨了《环境监测分析方法标准制订技术导则》(HJ 168—2020)附录B中规定的"数据对t值检验法"的不足及改进办法,即用数据对相对偏差和再现性限合格率作为判据,判断分析方法测定结果的一致性。对一组验证样品分别用两种分析方法进行了测定,在数据对t值检验的基础上,取各元素测定结果的相对偏差与相关限值进行比较,或者取两者的差值与基准分析方法标准规定的再现性限进行比较,利用合格率大小协助判断了两分析方法测定结果的一致性。研究结果表明,此方法符合日常质控技术规范中关于精密度的规定,实用性强,是一条将数理统计原理与专业知识相结合的合理技术路线。     

Ko method of quantification in neutron activation analysis as applied to environmental samples

The _Ko factor method in neutron activation analysis adopts all the principles of comparator method and can be used for the rapid determination of elemental comcentrations during routine monitoring of environmental samples. The method necessiates the use of same in-pile conditions, such as irradiation time, irradiation position and the type of neutron spectrum, for which the factors have been generated. The _{K_o} factors were estimated for various elements of environmental importance for three irradiation positions of Apsara Reactor at Bhabha Atomic Research Centre. Standard reference materials of soil and coal were used for all the elements except for Hg for which HgCl₂ was used. The concentration of the elements determined using these factors in a flyash standard reference material revealed good agreement within 10% of the certified values. The efficacy of the method compared well with that of specific element comparator method as revealed by the elemental concentrations obtained by both the techniques.     

饶河入鄱阳湖口处沉积物中重金属分布特征及形态研究

为了解饶河入鄱阳湖湖口重金属污染状况,在鄱阳湖饶河入湖段设置了3个采样点,用原子吸收分光光度计对沉积物进行了重金属Cu、Pb、Zn的测定,分析了这3种元素在各采样点的形态分布特征.结果表明:饶河人鄱阳湖口处沉积物中Cu、Pb、Zn的污染较为严重,呈现出复合污染的趋势.该区域沉积物中3种元素的分布受水流的影响较大,其形态...     

Ligustrum lucidum Ait. f. Leaves as a Bioindicator of the Air-Quality in a Mediterranean City

The concentration of 11 elements, Ba, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Zn and V, have been determined in leaves of Ligistrum lucidum Ait. f. growing in Palermo, by simultaneous inductively coupled plasma mass spectrometry. A total of 72 samples from six different sites were investigated to deduce the bioindicator ability of this species. Differences were found in the element concentrations in the leaves from the different sites and, in general, anthropogenic pollutant patterns match traffic levels. This paper describes and discusses the spatio-variations of the different elements. Cluster analyses established three different groups giving an idea about the origins of the elements. Results demonstrate that this species is useful as a bioindicator in a Mediterranean climate, especially as it has the added advantage of being an evergreen tree.     

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。     

Evaluation of the methyl ester O-methyl acetate derivative of muramic acid for the determination of peptidoglycan in environmental samples by ion-trap GC-MS-MS

Muramic acid (MA) is a unique amino sugar that is a constituent of the peptidoglycan (PG) present in prokaryotic cell walls. MA can serve as a marker for quantifying bacterial load, e.g. in indoor environments, by using gas chromatography-tandem mass spectrometry (GC-MS-MS). We demonstrated recently that the methyl ester O-methyl acetate (MMA) derivative can be used to detect MA in house dust by ion-trap GC-MS-MS. However, since the MMA derivative is not formed from free MA quantification was not optimal. Here we report 1) significant improvements in sample preparation of the MMA derivative and 2) an evaluation of the performance of derivative, using for comparison the alditol acetate derivative, the gold standard in quantitative trace analysis of MA in complex matrices. The MMA derivative was analysed using an MS instrument with internal ionization and the alditol acetate derivative was analysed using an instrument with external ionization. 13C-labelled cyanobacteria, containing MA in their PG, were used as the internal standard. A linear relationship was found between the two methods in studies on 27 parallel samples of airborne dust from school classes collected on filters. Although the analytical sensitivity of the MMA derivatives was somewhat slightly lower than of the alditol acetate derivative, this may be due to differences in yield of derivative, sample clean-up efficiency, or different performance of the GC columns or MS instruments. However preparation of the MMA derivative is quick and compatible with preparation of methyl esters of 3-hydroxy fatty acids (used as markers of Gram negative endotoxin) allowing the levels of both markers to be determined in the same dust sample. In conclusion, the MMA procedure can be used to determine MA in environmental samples with good reproducibility provided the concentration of the 13C-labelled MA internal standard in the cyanobacteria is first determined with an alternative method.     

不同滤筒中无机元素含量探讨

选择国内10家制造商的玻璃纤维滤筒和国外2家制造商的石英滤筒,分别测定空白滤筒中的铍、铬、铅等17种元素,探讨不同滤筒中各元素的含量分布,同时结合相关分析方法标准的质控要求,评价各制造商玻璃纤维滤筒在废气监测中的适用性。     

Risk assessment of trace elements in cultured freshwater fishes from Jiangxi province,China

The levels of trace elements (As, Cd, Cr, Cu, Fe, Ni, Pb, Se, and Zn) in eight species of cultured freshwater fishes from Jiangxi province were determined by inductively coupled plasma-mass spectroscopy. All the studied trace element levels in fish muscles from Jiangxi province did not exceed Chinese national standard and European Union standard, and they were often lower than previous studies. The calculated target hazard quotient values for all the studied trace elements in fish samples were much less than 1, suggesting that the studied trace elements in fish muscles from Jiangxi province had not pose obvious health hazards to consumers. As and Cd concentrations in northern snakehead were much higher than that in other fishes, demonstrating that this fish species could be valuable as a bioindicator of As and Cd in environmental surveys. In addition, the highest concentrations of Fe, Zn, and moderate contents of other essential trace elements in crucian carp indicated that crucian carp could be a good nutrient source of essential trace elements for human health.