... Eng. Sci., 1994, 34, 390 . 23, MD Petit-Domínguez, H. Shon, WR Heineman and CJ Sellskar, Anal... more ... Eng. Sci., 1994, 34, 390 . 23, MD Petit-Domínguez, H. Shon, WR Heineman and CJ Sellskar, Anal. Chem., 1997, 69, 703 Article ChemPort . 24, A. Jiménez-Morales, Ph.D. Thesis, Universidad Carlos III de Madrid, Spain, 1999 . 25, S. Feliu, JC Galván and M. Morcillo, Prog. Org. ...
A toposequence of limestone-developed soils was studied at a piedmont nearby Itaetê town, in the ... more A toposequence of limestone-developed soils was studied at a piedmont nearby Itaetê town, in the region so-called Chapada Diamantina of the State of Bahia. The study area involves 3,646 hectares where has recently been settled down 200 families. This settlement area, denominated Baixão, is located in a semi-arid stretch with an annual precipitation rate of 715.8 mm. Its relief presents
A simultaneous microdetermination of iron and copper at sub-mg/L level by solid phase derivative ... more A simultaneous microdetermination of iron and copper at sub-mg/L level by solid phase derivative spectrophotometry has been developed. The compounds TPTZ (2,4,6-tripyridyl-1,3,5-triazine) and Neocuproine (2,9-dimethyl-1,10-phenanthroline hydrochloride), were used as chromogenic reagents to form a blue iron complex and an orange copper complex, respectively (pH ¼ 5.0), which are fixed and concentrated on a cation-exchange resin sephadex sp C-25. The influence of experimental variables on the retention of the complexes on the resin are discussed. The signals in derivative units were measured directly on the solid, packed in a 1 mm spectrophotometric cell. The characteristic amplitude of the signals at 622.0 and 477.0 nm in third-derivative spectra are useful for quantitative determination of iron (0.195-120 ng mL À1 ; RSD ¼ 1.8%) and copper (0.451-300 ng mL À1 ; RSD 1.3%). The method was applied to the iron and copper determination in different types of water, respectively.
... M. INÉS TORAL (1) , NELSON LARA (1) , A. EUGENIA TAPIA (2) , CLAUDIO TORRES (2) , y PABLO RIC... more ... M. INÉS TORAL (1) , NELSON LARA (1) , A. EUGENIA TAPIA (2) , CLAUDIO TORRES (2) , y PABLO RICHTER (3) . ... [ Links ]. 8. R. Canals, JM Caldero, Afinidad, 37 (369), 435-438 (1980). [ Links ]. 9. A. Avgerinos , G. Athanasiou, S. Malamataris, J. Pharm. Biomed. ...
A microdetermination of iron at sub-mug/L level by derivative spectrophotometry has been develope... more A microdetermination of iron at sub-mug/L level by derivative spectrophotometry has been developed. The compound TPTZ (2, 4, 6-tripyridyl-1, 3, 5-triazine) was used as chromogenic reagent to form a blue complex (pH= 5.0), which is fixed and concentrated on a cation-...
A second derivative spectrophotometric method has been developed for the determination of palladi... more A second derivative spectrophotometric method has been developed for the determination of palladium and platinum in mixtures. The method is based on the formation of the platinum and palladium complexes with 3-(2-thiazolylazo)-2, 6-diaminopyridine,(2, 6-TADAP), in ...
... Eng. Sci., 1994, 34, 390 . 23, MD Petit-Domínguez, H. Shon, WR Heineman and CJ Sellskar, Anal... more ... Eng. Sci., 1994, 34, 390 . 23, MD Petit-Domínguez, H. Shon, WR Heineman and CJ Sellskar, Anal. Chem., 1997, 69, 703 Article ChemPort . 24, A. Jiménez-Morales, Ph.D. Thesis, Universidad Carlos III de Madrid, Spain, 1999 . 25, S. Feliu, JC Galván and M. Morcillo, Prog. Org. ...
A toposequence of limestone-developed soils was studied at a piedmont nearby Itaetê town, in the ... more A toposequence of limestone-developed soils was studied at a piedmont nearby Itaetê town, in the region so-called Chapada Diamantina of the State of Bahia. The study area involves 3,646 hectares where has recently been settled down 200 families. This settlement area, denominated Baixão, is located in a semi-arid stretch with an annual precipitation rate of 715.8 mm. Its relief presents
A simultaneous microdetermination of iron and copper at sub-mg/L level by solid phase derivative ... more A simultaneous microdetermination of iron and copper at sub-mg/L level by solid phase derivative spectrophotometry has been developed. The compounds TPTZ (2,4,6-tripyridyl-1,3,5-triazine) and Neocuproine (2,9-dimethyl-1,10-phenanthroline hydrochloride), were used as chromogenic reagents to form a blue iron complex and an orange copper complex, respectively (pH ¼ 5.0), which are fixed and concentrated on a cation-exchange resin sephadex sp C-25. The influence of experimental variables on the retention of the complexes on the resin are discussed. The signals in derivative units were measured directly on the solid, packed in a 1 mm spectrophotometric cell. The characteristic amplitude of the signals at 622.0 and 477.0 nm in third-derivative spectra are useful for quantitative determination of iron (0.195-120 ng mL À1 ; RSD ¼ 1.8%) and copper (0.451-300 ng mL À1 ; RSD 1.3%). The method was applied to the iron and copper determination in different types of water, respectively.
... M. INÉS TORAL (1) , NELSON LARA (1) , A. EUGENIA TAPIA (2) , CLAUDIO TORRES (2) , y PABLO RIC... more ... M. INÉS TORAL (1) , NELSON LARA (1) , A. EUGENIA TAPIA (2) , CLAUDIO TORRES (2) , y PABLO RICHTER (3) . ... [ Links ]. 8. R. Canals, JM Caldero, Afinidad, 37 (369), 435-438 (1980). [ Links ]. 9. A. Avgerinos , G. Athanasiou, S. Malamataris, J. Pharm. Biomed. ...
A microdetermination of iron at sub-mug/L level by derivative spectrophotometry has been develope... more A microdetermination of iron at sub-mug/L level by derivative spectrophotometry has been developed. The compound TPTZ (2, 4, 6-tripyridyl-1, 3, 5-triazine) was used as chromogenic reagent to form a blue complex (pH= 5.0), which is fixed and concentrated on a cation-...
A second derivative spectrophotometric method has been developed for the determination of palladi... more A second derivative spectrophotometric method has been developed for the determination of palladium and platinum in mixtures. The method is based on the formation of the platinum and palladium complexes with 3-(2-thiazolylazo)-2, 6-diaminopyridine,(2, 6-TADAP), in ...
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