动态反应池-电感耦合等离子体质谱法测定大气降水中的钠、镁、钾、钙离子研究

应用电感耦合等离子体质谱法测定大气降水中的钠、镁、钾、钙离子,通过优化质谱仪工作参数和动态反应池参数等方式,提高检测方法灵敏度,降低质谱干扰,以获得更低的背景等值浓度与检出限,通过国家标准样品的分析与实际样品加标回收试验,证实了方法的线性、精密度、准确度等均符合测定要求,对比原子吸收光度法、离子色谱法具有多元素同时分析,速度快,空白低,干扰小,操作简单等优点,适合大批样品的分析.     

海水管系中异种金属管道耦接腐蚀模拟研究

目的 研究船舶海水管系中常见异种金属管道之间的电偶腐蚀问题。方法 使用COMSOL Multiphysics软件,模拟研究紫铜（TP2Y）/#20钢、B10铜合金/921A钢、921A钢/锡青铜（XQT）耦接管道在3.5%NaCl溶液中管道内表面的电位、电流密度分布规律及耦接60 d后的电偶腐蚀状况。结果 异种金属管道耦接情况时,紫铜、B10铜以及锡青铜管道作为电偶腐蚀偶对中的阴极而受到保护,20号钢和921A钢管道为阳极,发生电偶腐蚀。当紫铜/20号钢管道耦接时,紫铜管道受保护长度距离耦接处约425 mm,而20号钢管道的电偶腐蚀长度距法兰耦接处约500mm;当B10铜合金/921A钢耦接时,B10铜合金管道受保护长度约500 mm,921A钢管道受到电偶腐蚀的长度约780 mm;当921A钢/锡青铜管道耦接时,锡青铜管道受保护长度约620 mm,而921A钢管道电偶腐蚀长度约820 mm。模拟结果还表明,当耦接时间达60 d后,紫铜与20号钢管道耦接时,20号钢管道内壁靠近处的腐蚀深度最大约为5.57μm;B10与921A钢管道耦接时,921A钢管道内壁的腐蚀深度达到8.31μm;...     

沉淀分离富集-电感耦合等离子原子发射光谱测定土壤中可溶态稀土元素

研究电感耦合等离子体原子发射光谱测定土壤中微量可溶态稀土元素的方法。在适宜的ｐＨ＝１０－１１条件下,以ＭｇＣｌ２为载体沉淀分离除去浸提液中的大部分基体杂质如Ｎａ＾＋,Ａｃ＾－,Ｃａ＾２＋,Ｍｇ＾２＋等,有效地消除了这些杂质的干扰,提高了测定方法的准确度;同时,待测可溶态稀土元素被沉淀集,样品中总稀土及单一稀土加标回收率为８８％－１１０％,样品测定结果满意,方法简便快速。     

高效液相色谱-电感耦合等离子体质谱联用测水中有机汞

建立了高效液相色谱-电感耦合等离子体质谱联用技术(HPLC-ICP-MS)测定水样中甲基汞、乙基汞、苯基汞等3种有机汞的分析方法。采用醋酸铵-L-半胱氨酸缓冲盐及甲醇体系组成的流动相按一定比例进行梯度洗脱,Agilent Zorbax Plus C18柱分离,经前处理的水样在液相色谱中分离后,进入电感耦合等离子体质谱检测其甲基汞、乙基汞、苯基汞的浓度。3种有机汞化合物均在0.50~50.0μg/L范围内呈良好的线性关系,线性相关系数均大于0.999 5。仪器检出限为0.09~0.12μg/L,方法检出限为0.4×10-6~0.6×10-6mg/L,3种有机汞样品加标的RSD均小于11.3%,2个水平的加标回收率为74.4%~83.2%。     

液液萃取-HPLC-ICPMS联用技术测定水体中甲基汞

建立了二氯甲烷萃取,半胱氨酸-乙酸铵溶液反萃取,液相色谱-电感耦合等离子体质谱法测定水中甲基汞的方法。取样量为1 L时,方法检出限为0.1 ng/L,相对标准偏差为6.6%~13%,地表水、生活污水和工业废水3种实际水样的加标回收率分别为45.6%~70.5%、37.0%~65.6%、18.4%~61.8%。与5种甲基汞测定方法的前处理过程、分析仪器和检出限进行了比较,并讨论了无机汞的干扰情况及如何降低体系空白和消除无机汞干扰的质量控制手段。     

高分辨电感耦合等离子体质谱法测定地下水中稀土元素

采用高分辨电感耦合等离子体质谱法测定地下水中14种稀土元素,并选择Rh作内标,可消除测定中的质谱干扰和非质谱干扰,使方法在0μg/L~100μg/L范围内线性良好。方法检出限为0.002μg/L~0.005μg/L,实际水样的加标回收率为80.0%~117%,RSD为2.1%~3.8%。     

溴化衍生-三重四极杆气质联用法测定地表水中丙烯酰胺

采用溴化衍生-液液萃取法处理地表水,用三重四极杆气相色谱质谱联用仪测定样品中α,β-二溴丙烯酰胺,再换算成丙烯酰胺的质量浓度,该方法在20.0μg/L~500μg/L范围内线性良好,相关系数r为0.998,方法检出限为0.08μg/L。实际水样2个质量浓度水平的平均加标回收率分别为87.5%和92.2%,7次测定结果的RSD分别为9.1%和6.1%。用该方法测定黄河兰州段的黄河水和实验室自来水,结果均未检出。     

Distribution of heavy metals in surface water of Ranipet industrial area in Tamil Nadu, India

Ranipet industrial area is about 120 km from Chennai on Chennai-Bangalore highway and is a chronic polluted area identified by Central Pollution Control Board of India. It is one of the biggest exporting centers of tanned leather in India. The total number of industries located in and around Ranipet town are 240 tanneries along with ceramic, refractory, boiler auxiliaries plant, and chromium chemicals. Studies were carried out to find out the contamination of surface water bodies due to industrial effluents. The results reveal that the surface water in the area is highly contaminated showing very high concentrations of some of the heavy/toxic metals like Cadmium ranging from 0.2 to 401.4 μg/l (average of 51.1 μg/l), Chromium 2.4–1,308.6 (average of 247.2 μg/l), Copper 2.1–535.5 μg/l (average of 95.5 μg/l), Nickel 1.6–147.0 μg/l (average of 36.7 μg/l), Lead 6.4–2,034.4 μg/l (average of 467.8 μg/l) and Zinc 20.8–12,718.0 μg/l (average of 3,760.4 μg/l). The concentration levels of these metals are much above the permissible limits in surface water and are health hazards especially for the people working in the tannery industries. It was observed that the people in the area are seriously affected and suffering from occupational diseases such as asthma, chromium ulcers and skin diseases. Distribution of metals, their contents at different locations, and their effects on human health are discussed in this paper.     

In vivo and in vitro metabolism of tobacco-specific nitrosamine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), by the freshwater planarian, Dugesia japonica

Cigarette smoke is a risk factor for human health, and many studies were conducted to investigate its adverse effects on humans and other mammals. However, since large amounts of cigarette products are produced and consumed, it is possible that tobacco chemicals can end up in aquatic environments through several routes, thus influencing aquatic organisms. In this study, the presence of tobacco-specific nitrosamine (TSNA), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), in aquatic environment was demonstrated. Since toxic effects on and distribution patterns of tobacco chemicals in aquatic organisms were rarely studied, after results of an acute toxicity pretest were obtained, experiment was conducted to investigate the bioaccumulation pattern of NNK and distribution patterns of its metabolites, mainly 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), in NNK-treated freshwater planarians, Dugesia japonica. Results from in vivo and in vitro studies showed that NNK was readily converted to NNAL through the carbonyl reduction in bodies of NNK-treated planarians. Tissue concentrations of both chemicals increased in time- and dose-dependent manners. Furthermore, we examined the end products of NNK/NNAL α-hydroxylation in NNK-treated planarians, but only 1-(3-pyridyl)-1,4-butanediol was detected, suggesting that NNK metabolism in planarians partially differs from that in mammalian systems. This is the first report on NNK metabolism in an aquatic organism and can be used as a foundation for developing freshwater planarians as a new in vivo model for the study of NNK toxicology in the future.     

Polymer coating of copper oxide nanoparticles increases nanoparticles uptake and toxicity in the green alga Chlamydomonas reinhardtii

Copper oxide nanoparticles (CuO NPs) are frequently used in a polymer-coated form, to be included in paints or fabrics for antimicrobial properties. Their application in antifouling paints may lead to the contamination of aquatic ecosystems. However, the toxicological risk of NPs in the environment is hard to evaluate due to a lack of knowledge on the mechanisms of NP interaction with biological systems. In this study, we investigated the effect of polymer coating on CuO NP toxicity in the green alga Chlamydomonas reinhardtii by comparing bare and polymer-coated CuO NPs prepared from the same CuO nanopowder. Both CuO NP suspensions were toxic to C. reinhardtii after 6 h treatment to concentrations of 0.005-0.04 g L⁻¹. Bare and polymer-coated CuO NPs induced a decrease of Photosystem II activity and the formation of reactive oxygen species. Polymer-coated CuO NP was found to be more toxic than the uncoated CuO NP. The higher toxicity of CS-CuO NP was mainly associated with the increased capacity of polymer-coated CuO NP to penetrate the cell compared to bare CuO NPs. These results indicates that the high toxicity of polymer-coated CuO NPs in algal cells results of intracellular interactions between NPs and the cellular system.