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1.
Duolite GT-73 resin was used for the preconcentration of Hg(II) from hydrochloric acid media as well as separation of the analyte from diversity of the co-existing metal ions (Al, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Zn) in off-line column operation. Due to the high affinity of the resin to the transition metals, Hg was adsorbed alongside with the foreign metals investigated. A complete release of the concomitant metals from the resin without the desorption of Hg was carried out using solutions of HCl and HNO3. A quantitative recovery of Hg was obtained by digestion of the resin using a H2SO4 and H2O2 mixture in an open-vessel system. An enrichment factor of 40 was achieved. The devised procedure was applied for the determination of Hg(II) in tap-water samples. 相似文献
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H. Pohl 《Fresenius' Journal of Analytical Chemistry》1966,223(1):66
Ohne Zusammenfassung 相似文献
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Kimmo Smolander Risto J?rnstr?m Annika Sajalinna 《Fresenius' Journal of Analytical Chemistry》1989,335(4):392-394
Summary The matric effect of boric acid was investigated in the determination of iron in the primary circuit coolant water of nuclear power plants by furnace atomic absorption spectrometry. The effect of boric acid was of particular interest. The method was applied during refuelling and maintenance periods and the results were used to interpret the chemical changes in the water.
Einfluß von Borsäure auf die Bestimmung von Eisen in Reaktorkühlwasser durch GF-AAS相似文献
9.
Ehmke Pohl George M. Sheldrick Johann J. Blsterli Jrg Kallen Ren Traber Malcolm D. Walkinshaw 《Helvetica chimica acta》1996,79(6):1635-1642
The crystal structure of isocyclosporin A ( 1 ), a rearrangement product of the immunosuppressant drug cyclosporin A, has been determined at 193 (2) K. Crystals are orthorhombic with cell dimensions a = 26.684 (7), b = 26.936 (3) Å, c = 28.549 (7) Å, space group C2221. The structure was solved by direct methods and refined by full-matrix least-squares methods to a conventional R value of 0.110. In contrast to the structure of cyclosprin A in solution and in the crystal, isocyclosporin A ( 1 ) has no regular secondary structural elements. The backbone adopts an open, irregular conformation with cis amide bonds between residue 2 and 3, and 3 and 4, respectively. All the other amide bonds and the ester linkage are trans. Contrary to crystal structures of cyclosporin derivatives, this crystal structure is stabilized by two transannular and four intermolecular H-bonds. 相似文献
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S. Pohl 《无机化学与普通化学杂志》1983,498(3):20-24
Crystal Structure of AlI3 · 2 PI3:P2I5+ AlI4? The crystal structure of the title compound was determined from single crystal X-ray data. P2I5+AlI4? crystallizes in the orthorhombic space group Pbca, a = 1 088.3, b = 1 827.3, c = 2 031.6 pm, V = 4040 · 106 pm3, Z = 8. The P2I5+ and AlI4? ions are connected by weak iodine-iodine bonds (I? I distances between 343.5 and 376.3 pm). The mean P? I and Al? I bond lengths were found to be 240.9 and 252.9 pm respectively. 相似文献