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《Analytical letters》2012,45(16):1431-1439
Abstract Crown ether-potassium ion complex extracts selectively copper-zincon anion complex as ion-pairs into chloroform phase in the presence of copper-zincon and zinc-zincon chelate anion, whereas quarternary ammonium ion extracts both anions. By measuring the absorbance of the chloroform phase at 615 nm, copper in the presence of zinc has been determined spectrophotometrically. The composition of extracted species was estimated to be Cu2+-zincon4?-(KL+)2. 相似文献
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聚乙二醇双水相萃取光度法测定锌 总被引:2,自引:0,他引:2
A novel method of extraction spectrophotometric determination of Zn~(2+) in aqueous two-phase system formed by polyethylene glycol-2000,sodium sulfate and zincon has been established.Amounts of PEG solution,zincon solution,sodium sulfate added and the acidity of the system were optimized.The interference effects of various coexistent ions and the method to remove the interference were investigated.The Zn-zincon complex that had been formed in the presence of H_2BO_3-Na_2B_4O_7 buffer solution at pH 7.4 was extracted into the upper PEG-rich phase,and the absorbance of the extracted complex in the upper PEG-rich phase was measured at 630 nm.The apparent molar absorptivity was 7.3 × 10~4 L / (mol·cm).Beer's law was obeyed over the range of 0~2.0 μg / mL Zn~(2+).The analytical results obtained for Zn~(2+) in water samples were in good agreement with values measured by atomic absorption spectrometry. 相似文献
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《Analytical letters》2012,45(6):355-358
Abstract Two methods are described for the determination of sulphate in the range of 200 μg to 100 mg by dissolving precipitated barium sulphate in excess of EDTA at pH 12.5. A titrimetric procedure involves back titration of excess EDTA with a standard zinc solution, while a complementary spectrophotometric method makes use of the stability of the barium EDTA complex in the presence of an excess of zinc ions; the latter are reacted with zincon and are equivalent to the amount of sulphate present. 相似文献
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Lei Chen Yeonju Park Hyeongkuyn Seo Wonjin Hong Young Mee Jung Bing Zhao 《Journal of Raman spectroscopy : JRS》2011,42(11):1963-1966
This paper demonstrates the potential of using a resonance Raman (RR) based method for the quantitative evaluation of protein concentrations. This method was applied to determine the concentration of bovine serum albumin (BSA) protein using zincon. In the protein–zincon liquid mixture, the number of unbound zincon molecules decreased markedly as the protein concentration increased because of the high affinity of zincon for proteins. We successfully detected very low concentrations of BSA (∼1 ng/ml) using this method, which demonstrates its great potential for the detection of proteins over a much wider range of concentrations in proteomic studies. This new RR‐based method allows the detection of proteins in lower concentration than with the UV–vis‐based and other protein assays commonly used in biochemical laboratories. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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将锌试剂用简单搅拌的方法负载在D-290型大孔阴离子交换树脂上制成锌试剂负载树脂.考察了该树脂在酸碱溶液中的稳定性,吸附金属离子的选择性,对Cu~(2+)的吸附速率和吸附容量等特性;试验了柱上定量吸附和洗脱Cu~(2+)的实验条件;建立了用该负载树脂经柱法分离富集后原子吸收测定自来水中及ZuSO_4、CdCl_2等盐类中微量铜的分析方法. 相似文献
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硫酸铵-锌试剂-Tween-80体系萃取分离铜(Ⅱ)、钴(Ⅱ)、镍(Ⅱ)、锌(Ⅱ)、镉(Ⅱ)、锰(Ⅱ) 总被引:5,自引:0,他引:5
研究了(NH4)2SO4-Zincon(锌试剂)-Tween-80体系萃取分离金属离子Cu(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)、Zn(Ⅱ)、Cd(Ⅱ)、Mn(Ⅱ)的行为。试验表明,Cu(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)在pH6~9范围内,与Zincon形成的螯合物可被Tween-80相完全萃取,而Zn(Ⅱ)、Cd(Ⅱ)、Mn(Ⅱ)基本不被萃取,进而实现了Cu(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)与Zn(Ⅱ)、Cd(Ⅱ)、Mn(Ⅱ)混合离子的定量萃取分离。 相似文献
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