Sentence:  Abelson and Rawson , using a stepwise <WSD>elution</WSD> scheme , fractionated whole sera containing ABO and Rh antibodies on diethylaminoethyl DEAE cellulose and carboxymethyl cellulose . 
Meaning of the word marked with <WSD> tags:  the process of extracting one material from another by washing with a solvent to remove adsorbed material from an adsorbent (as in washing of loaded ion-exchange resins to remove captured ions); used to obtain uranium ions