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A Study Of The Gelation Of Air-Setting Refractory Mortars, James Irving Mueller

Doctoral Dissertations

"Three basic mortar formulae were used in this investigation, each mix having some different materials present and each having its own gelling characteristics. The study was directed along the theory that the dry materials used play an important part in the hardening. Certain admixtures were tested and several were found to improve the workability after storage. The presence of additional sodium ions in the mortar was found to be helpful in overcoming the gelation but these tended to lower the refractoriness of the mortar.

A study was made of the base exchange capacities of the dry materials and the material …

A Study Of Certain Ferromagnetic Alloys In The Systems Copper-Manganese-Indium And Copper-Manganese-Gallium, Frederick Arthur Hames

Doctoral Dissertations

"In 1898 F. Heusler discovered that certain alloys containing only copper, manganese, and tin are ferromagnetic. Since that time, ferromagnetic alloys have been reported to occur in the ternary systems copper-manganese-aluminum, copper-manganese-arsenic, copper-manganese-boron, copper-manganese-antimony, copper-manganese-zinc, silver-manganese-aluminum, and silver-manganese-tin. Such ferromagnetic alloys containing only non-ferromagnetic elements have come to be called "Heusler alloys."

From the metallographic standpoint, the ferromagnetic copper-manganese-aluminum and copper-manganese-tin alloys have been the most fully investigated of the Heusler alloys. These alloys owe their ferromagnetism to the beta phases in their respective systems. The structure of the beta phase is based on a body-centered cubic lattice.

In view …

A Study Of The Flow Properties Of Concentrated Clay-Water Mixtures, William Joseph Smothers

Doctoral Dissertations

"The study of flow properties of many substances is of prime importance in varied industries. The ceramic industry is mainly concerned with these measurements on a relatively stiff ceramic body, i.e., one which contains only enough water to retain its shape after the deforming force is relieved.

Various types of instruments have been devised to measure flow properties in the so-called "true plastic range." Since the primary measurements were made on instruments of the transpiration type to devise the laws of viscous and plastic flow, it was felt that an instrument employing the flow of the plastic material through an …

Pyrochemical Changes In Missouri Halloysite, Frank Joseph Zvanut

Doctoral Dissertations

"For centuries it has been known that the application of heat to a clay or a clay body produces changes that make it an entirely different substance from the original raw clay. Ever since the earliest civilizations produced crude building brick by baking formed clay bodies in the sun's rays, mankind has been speculating on the nature of the changes that convert soft, friable, plastic clays into hard, strong, non-plastic, rock-like masses. It has been only within the last two decades, however, that progress has been made in the solution of problems dealing with the resultant products in fired clay …