| Project/Area Number |
15550066
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Analytical chemistry
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| Research Institution | University of Yamanashi |
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Principal Investigator |
KAWAKUBO Susumu University of Yamanashi, Department of Research Interdisciplinary Graduate School of Medicine and Engineering, Associate Professor, 大学院・医学工学総合研究部, 助教授 (90143958)
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| Project Period (FY) |
2003 – 2004
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| Project Status |
Completed (Fiscal Year 2004)
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| Budget Amount *help |
¥2,700,000 (Direct Cost: ¥2,700,000)
Fiscal Year 2004: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2003: ¥1,800,000 (Direct Cost: ¥1,800,000)
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| Keywords | Copper ion / Catalytic reaction / Catalytic determination / Humic acid / Fluorometric determination / Speciation analysis / Flow analysis |
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| Research Abstract |
1.Determinable reactive species
A catalytic spectrophotometric determination method for speciation of copper was developed using a copper-catalyzed oxidation of ascorbic acid in the presence of o-phenylenediamine. Reactive species of copper were characterized by a complexation study of oxalato-copper species. The study revealed that the reactive copper species were Cu^<2+> and Cu^<II>L_n (n≦2 for an unidentate and n=1 for bidentate ligand (L)).
2.Instrumentation of flow system for speciation analysis
For determination of reactive copper, PTFE tube used for the flow system adsorbs copper on its inner wall and seriously interfered with the determination. A manifold with individual flow lines for each reagent and sample solutions and a carrier solution with aluminum effectively inhibited the adsorption of copper. Copper was determined with an error of 1 ng/ml and a sampling frequency of 6 samples/h. A flow line for fluorometric determination of humic substances was incorporated with the flow system for copper. As humic acid, humic substances were simultaneously determined up to 200 ng/ml with an error of 10 ng/ml.
3.Application
The proposed analytical system was applied to the speciation of copper and humic acid in the presence of aluminum in an artificial river water sample containing copper(II), humic acid, iron(III) and silicate. Decrease of concentrations of reactive copper and humic acid suggested the formation of humic aggregates containing copper. The effect of fluoride ions in the presence of aluminum was also studied for the same artificial sample.
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