| Project/Area Number |
02640444
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
分析・地球化学
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| Research Institution | Nagoya Institute of Technology |
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Principal Investigator |
YUCHI Akio Nagoya Institute of Technology Faculty of Engineering, Lecturer, 工学部, 講師 (60144193)
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| Project Period (FY) |
1990 – 1991
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| Project Status |
Completed (Fiscal Year 1991)
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| Budget Amount *help |
¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1991: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1990: ¥1,000,000 (Direct Cost: ¥1,000,000)
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| Keywords | Fluoride Ion / Spectrophotometry / Mixed Ligand Complex / Chelating Reagent / Zirconium / Flow Injection Analysis / 吸光光度分析 |
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| Research Abstract |
Semi-xylenol Orange was, as its zirconium(IV) complex, a promising reagent for spectrophotometric determination of fluoride. Experimental conditions were optimized for practical use. The sensitivity is almost the same as La-Alizarin Complexon method, but a reagent blank is low and the reaction concludes within a minute. Flow injection analysis was successfully applied to this reaction system.
The equilibrium relevant to this color change was studied using a fluoride ion-selective electrode. A partly hydrolyzed parent complex reacts with fluoride to form mixed ligand complexes. The phenolic oxygen atom made free by the partial hydrolysis again coordinates to zirconium upon mixed ligand complex formation. This finding helps the design of new organic reagents.
Effect of a side-arm on formation of the mixed ligand complex was studied using simpler ligands (L) ; aminopolycarboxylates. DTPA and DPTA complexes do not react with fluoride. In the case of potentially decadentate TTHA, a protonated complex ZrHL has fairly high affinity to fluoride, whereas a complex ZrL does not. In the case of HEDTA, a complex ZrL has a higher stability constant for fluoride than EDTA or CDTA complex. The complex ZrH-_1L formed by deprotonation from alcoholic OH group, on the other hand, has much lower affinity to fluoride.
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