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Wegscheider Donald Leyden received a BS in chemistry from Kent State Universi ty and MS and PhD degrees in ana lytical chemistry from Emory Univer sity. He is currently Phillipson Pro fessor of Environmental and Mining Chemistry at the University of Den ver. Ley den's research interests in clude chelating ion-exchange resins, NMR studies of proton exchange re actions, preconcentration of trace ions prior to X-ray fluorescence anal ysis, and the chemical modification of surfaces. Wolfhard Wegscheider received his doctorate in technical sciences from the Technical University of Graz, Austria, and worked later under Ley den as a Fulbright scholar. His re search interests include sample prep aration techniques for multielement analyses and mathematical tech niques in analytical chemistry. He is currently universit&tsdozent for ana lytical chemistry at the Technical University of Graz.
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ANALYTICAL CHEMISTRY, VOL. 53, NO. 9, AUGUST 1981 · 1065 A
