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A selective Spectrophotometric method has been developed for the trace determination of copper after adsorption of its 1-phenyl-4,4,6-trimethyl(1H, 4H)-pyrimidine-2-thiol (PTPT) complex onto microcrystalline naphthalene. The complex is quantitatively adsorbed on naphthalene in the pH range 7.5–11.5, separated by filtration, dissolved in dimethylformamide (DMF) and determined spectrophotometrically at 400 nm. Beer's law is obeyed in the concentration range 2.5–37.5 g of copper in 10 ml of DMF. The molar absorptivity and Sandell's sensitivity are 1.30 × 1041 · mol–1 · cm–1 and 0.0048g cm–2, respectively. Ten replicate analyses of a solution containing 20.0 g of copper gave a mean absorbance of 0.410 with a relative standard deviation of 0.91 %. The interferences of various ions have been studied and the method has been validated by the determination of copper in various standard reference materials, beers, wines, human hair, goat liver and environmental samples.On leave from St. Stephen's College, Delhi 110 007, India 相似文献
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M. F. Hussain M. Katyal B. K. Puri Y. Takagi 《International journal of environmental analytical chemistry》2013,93(4):525-531
Abstract A sensitive method has been developed for the direct atomic absorption spectrometric determination of zinc, antimony and lead after coprecipitation of their trifluoroethylxanthates onto microcrystalline naphthalene. The metal xanthates are quantitatively coprecipitated over the pH ranges: Zn, 5.9–8.4; Sb, 4.0–6.0 and Pb, 4.0–11.0. The solid mass consisting of the metal complex and naphthalene is dissolved in DMF. This solution is aspirated into an air-acetylene flame at 213.9, 217.6 and 217.0nm for Zn, Sb and Pb, respectively. Beer's law is obeyed in the concentration range 2–50, 3–90 and 5–60 μg of Zn, Sb and Pb, respectively in 10ml of the final DMF solution. RSDs are at the ± (0.5–0.6)% level (n=10). The concentration for 1% absorption is 0.019, 0.035 and 0.060μg/ml for Zn, Sb and Pb, respectively. The method is suitable for the preconcentration of the metals from a larger volume of the aqueous phase, and has been employed for their determination in standard reference materials. It may be employed for the simultaneous determination of Zn, Pb and Sb in a solution by pH control. 相似文献
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Metal complexation with 2-hydroxy-6-methylpyridine-3-carboxylic acid has been studied. The ligand finds use in detection and determination of iron (III). The order of stability constants of the bivalent transition metal complexes is Cu > Zn > Fe > Ni > Co > Mn. b]¦de¦Die Komplexbildung von Metallen mit 2-Hydroxy-6-methylpyridin-3-carbonsäure wurde untersucht. Der Ligand findet Verwendung beim Nachweis und bei der Bestimmung von Eisen(III). Die Reihenfolge der Stabilitätskonstanten der Komplexe mit zweiwertigen Überg angsmetallen ist Cu > Zn > Fe > Ni > Co > Mn. 相似文献
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Prashant Singh Pradeep Kumar Anju Katyal Rashmi Kalra Sujata K. Dass Satya Prakash Ramesh Chandra 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(3):983-991
In the present work, we report the synthesis and characterization of novel charge-transfer complexes of thiazolidine-2,4-dione (TZD) with sigma acceptor (iodine) and pi acceptors (chloranil, dichlorodicyanoquinone, picric acid and duraquinone). We also evaluated their thermal and electrochemical properties and we conclude that these complexes are frequency dependent. Charge-transfer complex between thiazolidine-2,4-dione and iodine give best conductivity. In conclusion, complex with sigma acceptors are more conducting than with pi acceptors. 相似文献
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Lead sulfide has been found to form stable glasses with GeS2 in the presence of GeS. Far-infrared transmission spectra of the glassy compositions x = 0.46, 0.23 and 0.115 in the pseudoternary (PbS)x (GeS2)0.70?x (GeS)0.30 and of the stoichiometric crystalline composition Pb2GeS4 have been observed for the first time. The results indicate a two optical mode behaviour of the compounds. The presence of the heavy lead atom in the GeS network seems to appreciably affect the bond bending modes of the GeS4 molecular unit without significantly disturbing its bond stretching vibrations. The presence of S3GeGeS3 molecular units in the amorphous compositions and their absence in Pb2GeS4 are indicated. 相似文献