摘要:

AbstractPart I of this investigation covers the development of reliable laboratory tests to indicate the relative properties of different clays with the primary consideration of their casting behavior. Methods are given for the determination of casting rate, permeability, water retention, fluidity, thixotropy, organic content, shrinkage, and dry strength. By determining the effect of varying increments of electrolyte on the foregoing properties, it is possible to select clays which have desirable casting characteristics for commercial use. Samples of fast‐ and slow‐casting kaolins and ball clays were used to indicate the utility of the methods employed; results are also given for two composite bodies. In developing the test procedures using the Büchner funnel (vacuum), the effect of the following factors was determined: mixing procedure, ratio of clay to flint, feldspar vs. flint as the nonplastic, electrolyte content, quantity of slip used, specific gravity of slip, slip temperature, aging, and vacuum pressure; The optimum procedure for testing clays was then evolved. Part II and Part III of this series of studies are in preparation for publica

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1944.tb14876.x

出版商:Blackwell Publishing Ltd    

年代:1944

数据来源: WILEY

摘要:

AbstractThe various methods for determining the degree of resistance of porcelain enameled cookingware to acid solubility are discussed. A method that overcomes many of the difficulties encountered in such a test and offers greater accuracy and reproducibility is described in detail.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1944.tb14877.x

出版商:Blackwell Publishing Ltd    

年代:1944

数据来源: WILEY

摘要:

AbstractThe cataphoretic velocity of three purified, monodisperse fractions of Florida kaolin was determined by the ultramicroscope method. The effect of particle size, kaolinite concentration, and electrolyte concentration on the migration velocity of the particles was observed. Calculations of zeta potential, charge density, and total charge were made for the various systems. It is shown that the zeta potential decreases with increasing particle size and increasing clay concentration. The plots of migration velocity versus electrolyte concentration follow the usual form for such curves, rising rapidly with the first electrolyte additions and flattening out as equilibrium is reached.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1944.tb14878.x

出版商:Blackwell Publishing Ltd    

年代:1944

数据来源: WILEY

摘要:

AbstractThe effect of variations in composition on optical properties was studied. The index of refraction is lowered by the substitution of fluorine and alumina for silica; the reciprocal dispersion, however, is increased by fluorine and lowered by alumina so that fluorine and alumina can be balanced against each other to give almost any desired optical properties within the field investigated, that is, in the range of 1.46 to 1.50 for index of refraction and 63 to 70 for the reciprocal dispersion.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1944.tb14879.x

出版商:Blackwell Publishing Ltd    

年代:1944

数据来源: WILEY