Lead and Zinc Ores: Flotation

of isotopically labelled vitamin D metabolites by HPLC. Journal of Chromatography 303: 229}233. Kaspersen FM, van Acquoy J, van de Laar GLM, Wagenaars GN and Funke CW (1984) Deuterium isotope effects in mianserin. Recueil Travaux Chimique de Pay-Bas 103: 32}36. Klein PD (1966) Occurence and signiRcance of isotope fractionation during analytical separation of large molecules. Advances in Chromatography 3: 3}65. Les\ etickyH L (1985) Isotope separation by chromatographic methods [in Czech]. Radioisotopy 26: 113}126. Lockley WJS (1989) Regiochemical differences in the isotopic fractionation of deuterated benzoic acid isotopomers by reversed phase HPLC. Journal of Chromatography 483: 413}418. Simon H and Palm D (1966) Isotope effects in organic chemistry and biochemistry [in German]. Angewandte Chemie 78: 993}1007. Tanaka N, Araki M and Kimata K (1986) Separation of oxygen isotopic compounds by reversed-phase liquid chromatography. Journal of Chromatography 352: 307}314. Tanaka N and Thornton ER (1977) Structural and isotopic effects in hydrophobic binding measured by HPLC. A stable and highly precise model for hydrophobic interaction in biomembranes. Journal of American Chemical Society 99: 7300}7306. Willi AV (1983) Isotope Effects in Chemical Reactions [in German]. Stuttgart: G. Thieme. Worth GK and Retallack RW (1988) Tritium isotope effect in high-pressure liquid chromatography. Analytical Biochemistry 174: 137}141. Yeung PKF, Hubbard JW, Baker BW, Looker MR and Midha KK (1984) Isotopic fractionation of N([H]methyl)chlorpromazine and N-([H]methyl)-7hydroxychloropromazine by reversed-phase high performance liquid chromatography. Journal of Chromatography 303: 412}416.