Seven coal samples with carbon contents ranging from 69.95% to 94.17% on a dry mineral matter-free (dmmf) basis were extracted with pyridine at reflw temperature for two weeks. The liquids obtained (coal extracts) were analyzed for molecular weight distribution by gel permeation chromatography at 35 "C using a solution of 10% pyridine and 90% tetrahydrofuran as the mobile phase. Calibration was done by use of anionically-prepared monodisperse polystyrene and by a series of polynuclear a Present address: Eastman Kodak, Rochester, NY, 14618.
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