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Rapid procedures were investigated for the analysis of commercial sugars for potassium, sodium, calcium, magnesium, chloride, sulfate, phosphate, and silicate without ashing of the sugar. The metallic constituents, particularly the alkali metals, are conveniently determined in a 5°Brix solution by flame photometry. The hydrogen flame was better than the acetylene because of lower radiation interferences.The flame photometric determinations for calcium and magnesium agreed well with the values obtained by titration with ethylenediaminetetraacetic acid, but the advantage is with the latter in many instances.Chloride was satisfactorily determined by conductometric titration and sulfate by turbidimetric measurements on barium sulfate. Soluble silicate and inorganic phosphate were measured by the intensities of the molybdenum blue formed under two different sets of conditions.

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Fine Ce‐Y oxide powders were prepared by coprecipitation of the carbonate, followed by calcination at 620°C. Hydrolysis of trichloroacetic acid was used to precipitate most of the material from a homogeneous solution; addition of ammonium bicarbonate and ripening of the precipitate were used to increase the yield to 68 to 70%. The precipitate apparently consisted of more than one phase and had an overall composition which suggested that it was a possible mixture of hydrated carbonate, hydroxycarbonate, and hydroxide. The calcined oxide powder was used to prepare an yttria‐doped ceria ceramic by hot‐pressing. The ceramic had the fluorite structure phase with a lattice constant of 0.541088 nm and a composition of Ce0.914Y0.086O1.957. The bulk density of the material was 6.96 g/cm3, or 99.4% of theoretical density. The ceramic had equiaxed grains, with an average dimension of 1 to 4 μm and with residual porosity mainly along the grain boundaries. Ac impedance properties of the chemically prepared oxide are compared with those of mechanically mixed and fired Y‐doped CeOZ.

The thermal decomposition of the ammonium sulfate, carbonate, nitrate, oxalate, and sulfate salts of praseodymium, neodymium, and samarium was investigated thermogravimetrically in the temperature range 25" to 1400°C. Each salt was decomposed at a heating rate of 2.5OC per minute. The pyrolytic sequences have been identified, and the temperatures of formation of intermediates and of the sesquioxides have been determined. The sesquioxide formation temperatures increased in the order samarium, neodymium, and praseodymium irrespective of the anion. The nonstoichiometric ranges between Pr6OI1 and Pr203 and the extent of these ranges have been determined for oxides derived from the carbonate, nitrate, and oxalate salts of praseodymium. The nonstoichiometric oxides of praseodymium were not observed in the decomposition of the alum and sulfate salts.