Sentence Examples

  • Marggraf demonstrated that alumina was another constituent.
  • The oxide is a black or brown powder according as it is prepared from the exalate or sulphate, and when pure it is non-fluorescent, but mixed with gadolinia or alumina it possesses this property.
  • The raw materials used in the manufacture are: (I) iron-free kaolin, or some other kind of pure clay, which should contain its silica and alumina as nearly as possible in the proportion of 2SiO 2: Al203 demanded by the formula assigned to ideal kaolin (a deficit of silica, however, it appears can be made up for by addition of the calculated weight of finely divided silica); (2) anhydrous sulphate of soda; (3) anhydrous carbonate of soda; (4) sulphur (in the state of powder); and (5) powdered charcoal or relatively ash-free coal, or colophony in lumps.
  • The precipitated alumina is filtered off, the filtrate evaporated and the ammonium salt of the acid purified by recrystallization.
  • Marggraf showed that alumina is one of the constituents of alum, but that this earth possesses peculiar properties, and is one of the ingredients in common clay (Experiences faites sur la terre de l'alun, Marggraf's Opusc. ii.