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• n  a high speed centrifuge used to determine the relative molecular masses of large molecules in high polymers and proteins
• v  subject to the action of an ultracentrifuge

• The researchers separated the two kinds in an ultracentrifuge.
• In this ultracentrifuge the molecular weight of the Stanley crystals was found to be about 17,000,000 units (17,000,000 times as heavy as a hydrogen atom).
• The ultracentrifuge, whirling at 50,000 revolutions per minute, separates the ingredients into layers, including one of pure crystalline virus.