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The coprecipitation method is widely used for the preconcentration of trace metal ions prior to their determination by flame atomic absorption spectrometry (FAAS). A simple and sensitive method based on coprecipitation of Fe(III) and Ni(II) ions with Cu(II)‐4‐(2‐pyridylazo)‐resorcinol was developed. The analytical parameters including pH, amount of copper (II), amount of reagent, sample volume, etc., were examined. It was found that the metal ions studied were quantitatively coprecipitated in the pH range of 5.0–6.5. The detection limits (DL) (n = 10, 3s/b) were found to be 0.68 µg L?1 for Fe(III) and 0.43 µg L?1 for Ni(II) and the relative standard deviations (RSD) were ≤4.0%. The proposed method was validated by the analysis of three certified reference materials (TMDA 54.4 fortified lake water, SRM 1568a rice flour, and GBW07605 tea) and recovery tests. The method was successfully applied to sea water, lake water, and various food samples. 相似文献
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Valfredo A. Lemos Emanuel V. dos Santos Vieira Eldevan dos Santos Silva Liz O. dos Santos 《洁净——土壤、空气、水》2012,40(3):268-271
A method for the determination of nickel in water was developed. The procedure involves preconcentration of nickel by using dispersive liquid–liquid microextraction. The Ni(II) ions were extracted in chloroform in the form of complex with the reagent 2‐(2′‐benzothiazolylazo)‐p‐cresol. Ethanol was used as the disperser solvent. After injection of the extracting mixture in a solution of nickel, a cloudy mixture was observed. A quick centrifugation induces phase separation and thus the settling of rich phase. The nickel content in the rich phase is measured by flame atomic absorption spectrometry. Under optimal conditions, the limit of detection and quantification obtained were 1.4 and 4.7 µg L?1, respectively. Some parameters used to characterize preconcentration systems, such as enrichment factor and consumption index were calculated and resulted in 29 and 0.34 mL, respectively. After optimization of variables and determination of analytical characteristics, the method was used for the analysis of certified reference materials (BCR‐713: wastewater, effluent and BCR‐414: plankton) and real water samples. 相似文献
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李芳清 《华东地质学院学报》2006,29(4):387-389
采用火焰原子吸收光谱法对南丰蜜桔叶片中的Cu,Zn,Mn,Fe,Co等5种元素的含量进行了测定,其方法简便、精密度高和灵敏度高。详细的研究了消解酸的种类、HNO3和HF的比例、消解酸的体积及消解时间对测定结果的影响。测定结果表明,南丰蜜桔叶片中铁和锌的含量较高。 相似文献
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介绍了应用编结反应器为吸附介质,流动注射在线置换吸附预富集消除Fe、Ca、Mn、Pb等共存金属离子的影响,与火焰原子吸收联用分析痕量银的方法,Ag(Ⅰ)吸收信号峰高比直喷时增感26倍,检出限为0.60μg/g。方法用于国家一级地质标准物质中Ag的测定,结果与标准值相符,5次测定的RSD≤4.8%。 相似文献
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含油岩石的荧光特征研究 总被引:1,自引:0,他引:1
在紫外光照射下,很多有机物质和部分无机物质能够发出不同颜色和亮度的荧光。本文研究了含油岩芯中岩石矿物的荧光特征,指出采用氯仿(或乙烷)试剂浸泡岩样是区别岩石矿物荧光的有效方法。本文着重对含油岩芯中有机质组成以及有机组分与荧光颜色的关系进行了深入的探讨,指出依据含油岩芯的荧光颜色可以进行油气水层的荧光解释。 相似文献
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C18键合硅胶柱在线富集/FIA-FAAS系统测定海水中痕量重金属 总被引:2,自引:0,他引:2
基于8-羟基喹啉金属螯合物在C_(18)键合硅胶上的吸附原理,在海水样品中加入少量8-羟基喹啉溶液,建立在线C_(18)键合硅胶柱富集,甲醇洗脱,洗脱液直接进入火焰的流动注射-火焰原子吸收光谱系统(FIA-FAAS)测定海水中痕量Cu,Ni,Cd和Zn的方法。富集倍数达80,进样频率为每小时30次。对Cu Ni,Cd和Zn测定的特征浓度分别为0.30,0.26,0.12和0.07μg/L;检出限(2σ)分别为0.07,0.05,0.02和0.01μg/L;相对标准偏差分别为2.7,2.1,2.8和2.5%;回收率分别为102,98,96和102%。本法快速简便,污染少,灵敏度高。 相似文献