环境样品中铅、锑、汞、硒形态分析研究进展

综述了环境样品中铅、锑、汞、硒形态分析的研究进展,以及光谱法、色谱法、毛细管电泳及其联用技术在形态分析中的应用,展望了环境样品痕量元素形态分析的发展前景。     

环境介质中硒的检测方法研究进展

结合国内外的研究进展,综述了环境介质中硒的各种检测方法。其中重点介绍了比较常用的测定方法,如原子吸收光谱法(AAS)、原子荧光光谱法(AFS)和电感耦合等离子体原子发射光谱法(ICP-AES)等,并展望了硒在检测方法上的发展趋势。     

异丙醇增感电感耦合等离子体质谱法直接测定土壤和沉积物中硒

提出了沸水浴混合酸法消解,以异丙醇为增感剂,电感耦合等离子体质谱直接测定土壤和沉积物中硒的方法。实验表明2mol/L硝酸-4mol/L盐酸混酸能有效溶出土壤和沉积物中各种形态的硒。相对于1%硝酸基体,4%(V/V)异丙醇基体中硒的ICP-MS响应值提高了12.1倍;而且4%(V/V)异丙醇基体可有效抑制硒的质谱干扰。ICP发射功率和雾化气流速是影响异丙醇在ICP-MS测定过程增敏效应的主要因素。以78硒为测定同位素,方法检出限为0.005mg/kg,实际样品测定精密度均小于5%。用于测定土壤和沉积物国家标准样品并对其消解液进行加标回收实验,结果令人满意。     

酸性土壤有效态硒浸提方法的研究

本文提出了酸性土壤有效硒的0.1MKH_2PO_4浸提法.土壤和植物的分析结果表明:0.1MKH_2PO_4浸提有效态硒能反映土壤对植物的供硒状况.黑麦幼苗试验进一步证明KH_2PO_4浸提有效态硒可以作为酸性土壤有效硒的指标.     

氢化物发生—原子荧光法测定河水中硒(Ⅳ)硒(Ⅵ)

在河水样品４ｍｏｌ／ＬＨＣｌ介质中硒生成氢化物，用氢化物发生法测定硒（Ⅳ）含量。将样品的４ｍｏｌ／ＬＨＣｌ溶液在沸水中加热还原硒（Ⅵ）至硒（Ⅳ）测定总量。总硒量减去硒（Ⅳ）量，分别求得硒（Ⅳ）和硒（Ⅵ）含量     

溴酸钾—酸性铬红—CTMAB动力学光度法测定硒的研究

根据痕量硒（Ⅳ）对溴酸钾氧化酸性铬红的褪色催化作用,建立了一种测定硒的新方法。检出限为4μg／L,硒的含量在20～240μg／L内符合比耳定律。方法用于食品中硒的测定,结果满意。     

石墨炉原子吸收法测定茶水中低含量硒

微量硒是人体必须的营养元素 ,有一定的防癌作用 ,但摄入量过多 ,则会引起硒中毒。喝茶是人们的习惯 ,因而对茶水中硒含量的监测甚为必要。今应用石墨炉原子吸收法直接测定茶水中的硒 ,取得了较为满意的结果。1　试验1 1　主要仪器与试剂岛津ＡＡ 680 0原子吸收光谱仪 ;ＧＦＡ -ＥＸ7石墨炉 ;ＡＳＣ - 61 0 0自动进样器 ;热解石墨管 ;硒空心阴极灯。ｌｇ/Ｌ硒标准储备液 :称取氧化硒 (ＳｅＯ2 ) 1 40 5 3ｇ移入 1Ｌ容量瓶中 ,加入氢氧化钠 2ｇ ,用少量水溶解后 ,稀释至刻度 ,摇匀 ;0 1 0 0ｍｇ/Ｌ硒标准工作液 :用时将 1 ｇ/Ｌ硒标准储备…     

氢化物发生原子荧光法在测定土壤中浸出硒、总硒的应用

应用氢化物发生原子荧光光谱法研究了测定基地土壤中的浸出硒、总硒的技术。称取一定量土样置于烧杯中,加蒸馏水间歇手动搅拌2小时后放置过夜,取上清液测有效硒;用HNO3-HF-HClO4分解法全量消解样品,同时做全程空白实验,样品处理后加入10%硫脲-10%抗坏血酸混合改进剂以消除Cu、Ag、Ni、Pd等金属离子的干扰,并以1%硼氢化钠为还原剂,在25%的盐酸介质中测定总硒。其浸出态硒测定的检出限为1.5×10-3mg/kg,总硒测定的检出限为0.032mg/kg。     

荧光法测定生物材料中微量硒

硒是动物和人类必须的微量元素,某些地区水、土壤、植物中硒含量很高而导致家畜发生地方性疾病,硒含量缺乏会使人类诱发心血管疾病和癌症,已引起国内外许多科学家的特别关注。生物样品中痕量硒的荧光法测定,具有灵敏度高,选择性好,操做简便等优点,但样品的消解方法十分关键。 K.Wmiehacl等,比较研究了HNO_3-Mg(NO_3)_2及     

玻碳金膜电极线性扫描微分阳极溶出伏安法分析测定水样中痕量硒（Ⅳ）及硒（Ⅵ）

本文采用玻碳预镀金膜电极为工作电极，研究了痕量硒（Ⅳ）在０．５ＭＨＮＯ３底液中的阳极格出行为。于－０．４Ｖ处电沉积，在＋０．８Ｖ（ｖｓ．ＳＣＥ）左右得到一灵敏的二次导数溶出峰。硒（Ⅳ）浓度在０．１５—１．６ｎｇ／ｍｌ和１．６－１２ｎｇ／ｍｌ范围内溶出峰电流与硒（Ⅳ）浓度之间呈良好的线性关系，相关系数分别为０．９９８３和０．９９８８，检出下限为０．０４ｎｇ／ｍｌ。用水浴加热盐酸还原法将水样中硒（Ⅵ）还原为硒（Ⅳ），从而用差减法测得样品中硒（Ⅳ）和硒（Ⅵ）的分别含量。     

Selenium in the Blackfoot, Salt, and Bear River Watersheds

Nine stream sites in the Blackfoot River, Salt River, and Bear River watersheds in southeast Idaho, USA were sampled in May 2001 for water, surficial sediment, aquatic plants, aquatic invertebrates, and fish. Selenium was measured in these aquatic ecosystem components, and a hazard assessment was performed on the data. Water quality characteristics such as pH, hardness, and specific conductance were relatively uniform among the nine sites. Of the aquatic components assessed, water was the least contaminated with selenium because measured concentrations were below the national water quality criterion of 5 g/L at eight of the nine sites. In contrast, selenium was elevated in sediment, aquatic plants, aquatic invertebrates, and fish from several sites, suggesting deposition in sediments and food web cycling through plants and invertebrates. Selenium was elevated to concentrations of concern in fish at eight sites (> 4 g/g in whole body). A hazard assessment of selenium in the aquatic environment suggested a moderate hazard at upper Angus Creek (UAC) and Smoky Creek (SC), and high hazard at Little Blackfoot River (LiB), Blackfoot River gaging station (BGS), State Land Creek (SLC), upper (UGC) and lower Georgetown Creek (LGC), Deer Creek (DC), and Crow Creek (CC). The results of this study indicate that selenium concentrations from the phosphate mining area of southeast Idaho were sufficiently elevated in several ecosystem components to cause adverse effects to aquatic resources in southeastern Idaho.     

Mercury, Methylmercury, and Selenium Concentrations in Eggs of Common Loons (Gavia immer) from Canada

Concentrations of Hg and Se were determined for a total of 125Common Loon (Gavia immer) eggs collected from lakes in Alberta, Saskatchewan, Ontario, Quebec, New Brunswick and NovaScotia, Canada between 1972 and 1997. Resulting data were compared to Hg and/or Se concentrations known or suspected tocause reproductive impairment in birds. Organic (methyl) Hg analyses were also performed on a subset of 24 loon eggs. Thirty-nine of 125 eggs had total Hg levels exceeding those (0.6 g g^-1 ww, or 2.5 g g^-1 dw)previously reported to be associated with reproductive impairment in common loons (Barr, 1986), and 9 of 125 eggshad Hg concentrations higher than the level associated withreproductive impairment in birds generally 1 g g^-1 ww; (Thompson, 1996). Selenium concentrations in loon egg samples were less than levels known to cause reproductiveimpairment in birds. A weak but significant positive correlation was observed between egg-Hg and -Se concentrations(r = 0.511, p < 0.05). On average, methylmercury accounted for about 87% of total Hg in 24 eggs analysed for both total and organic Hg. In this subset of eggs, the relationship between organic (methyl) Hg and Se was significant (r = 0.538, p = 0.007) while that found between inorganic Hg and Se in the same eggs was not significant (r = 0.353, p = 0.091). This relationship was unexpected and was contrary to relationships established for organic and inorganic Hg vs. Se in adult loon liver and kidney tissue (Scheuhammer et al., 1998b).     

氢化物发生原子荧光法测定饮用水中的微量硒

氢化物发生原子荧光法测定饮用水中的微量硒时。仪器条件和试剂的浓度选择很重要。本文对条件的最佳化进行了实验。并对方法的精密度、准确度和检出限进行了讨论。     

The American Dipper as a Bioindicator of Selenium Contamination in a Coal Mine-Affected Stream in West-Central Alberta, Canada

Elevated levels of selenium have been found in water and aquatic biota downstream from two open-pit coal mines in the Rocky Mountain foothills of Alberta. Birds are particularly sensitive to excessive dietary selenium. However, there is relatively little information on selenium accumulation in birds' eggs on fast-flowing mountain streams. We determined levels of selenium in water samples, caddisfly larvae and eggs of American dippers (Cinclus mexicanus) nesting on the Gregg River, downstream from the mines, and on reference streams in the same general vicinity. Selenium levels (mean, 95% confidence limits) in water samples and caddisflies collected from sites near dipper nests on the Gregg River (water: 4.26, 1.90–9.56 μg L⁻¹; caddisflies: 8.43, 7.51–9.46 μg g dry wt⁻¹) were greater than those collected from sites near nests on reference rivers (water: 0.38, 0.21–0.71 μg L⁻¹; caddisflies: 4.65, 4.35–4.97 μg g dry wt⁻¹). The mean (± 1SE) selenium level in dipper eggs from the Gregg River (6.3 ± 0.2 μg g⁻¹ dry wt) was significantly higher than it was in eggs from reference streams (4.9 ± 0.2 μg g⁻¹ dry wt). Concentrations of selenium in eggs were significantly correlated with those in water samples (r = 0.45). The maximum selenium level in eggs from the Gregg River (9.0 μg g⁻¹) may have been high enough to warrant concern from an ecotoxicological perspective. The American dipper can serve as a useful bioindicator of selenium contamination in mountainous, lotic ecosystems.     

二氨基联苯胺分光光度法测定水质中硒的方法改进

采用3.3＇-二氨基联苯胺分光光度法对测定水质中硒的方法进行改进,主要研究了样品中硒的测定条件,通过对不同显色波长、酸碱度显色条件、显色剂用量、酸碱度比色条件的研究,得出比较理想的定量分析条件。采用该方法测定硒,显色稳定,准确度、精密度均能达到要求。     

石墨炉原子吸收分光光度法测定地表水中硒的研究

研究了石墨炉原子吸收分光光度法测定地表水中硒过程中灰化电流的选择和加入基体改进剂减少干扰并提高灵敏度的方法。     

Microtrace Metalloids Speciation in Lakes Water Samples (Poland)

This paper presents the results of the determination of arsenic, antimony and selenium concentrations of inorganic speciation in surface water samples from Gniezno city (western Poland) and its neighborhood. The concentration of elements were up to 1.85 ng/ml for arsenic, 1.61 ng/ml for antimony and 0.45 ng/ml for selenium (detection limits: 0.04 ng/ml for As and Sb and 0.03 ng/ml for Se). A variety of concentrations for the determined elements has been obtained in waters from Gniezno city’s neighborhood and in water from down-town reservoirs which are under strong anthropogenic pressure.