Engineering Commons^™

A Study Of Relative Ionic Mobility Of Alkali Ions In Dilute Alkali-Boron Trioxide Glasses As Deduced From Space Charge Considerations, Theodore J. Planje

Doctoral Dissertations

"The extensive investigations in the past have conclusively established that the alkali ions are responsible for the electrical conductivity of glass in both the brittle and viscous states; however, with the exception of one investigation in the brittle state, little consideration has been given to determination of the mobility of the alkali ion in such glassy systems. A review of the literature pertaining to the electrical conductivity of glass is presented.

A method, based on the rate of development of the ionic space charge responsible for polarization of conductivity cell employing direct current voltages, is proposed as a means for …

The Volatility Of Metallic Sulfides And Their Treatment By Vacuum Metallurgy, Chi-Mei Hsiao

Doctoral Dissertations

"The purpose of this investigation is to determine the vapor pressure or volatility of the sulfides of the following metals by Langmuir's method: a) Zinc b) Cadmium c) Mercury d) Manganese e) Tin f) Lead g) Arsenic h) Antimony i) Molybdenum J) Iron k) Cobalt l) Nickel m) Copper n) Silver o) Calcium p) Aluminum.

The relation of this property to the position of the metals in the periodic table will be discussed, thus the vapor pressure or volatility of the remaining metals can be predicted as to the order of magnitude if the law of periodicity holds.

The possible …

A Study Of The Dissolution Of Titanium In Acids With Emphasis On Hydrofluoric Acid, Ping-Chao Chen

Doctoral Dissertations

"Titanium is practically a new metal. Although it was discovered by W. Gregor in 1791, the pure metal was not prepared until 1910 by M. A. Hunter, and it is only very recently that tremendous interest has been focused on this new metal, as evidenced by the activities of numerous leading laboratories and pilot plants.

The reasons that Ti is gaining increasing attention may be attributed to the natural abundance of Ti ores in reasonable concentration and, what is more important, to its unusual combination of physical and chemical properties. According to F. W. Clark’s classical geochemical data, Ti amounts …

Measurement Of Flotation Rate As A Function Of Particle Size, Thomas Martin Morris

Doctoral Dissertations

“The Problem. The rate of flotation of solid particles determines the percentage recovery of these particles which can be obtained during a given time interval. An examination of operating data from a flotation plant shows that percentage recovery varies with the size of particle.

Many investigators have explored the problem of measuring flotation rate. In most cases the results obtained were expressed qualitatively. The results obtained by one worker were often at variance with results reported by another worker.

This investigation was undertaken with the object of (1) quantitatively measuring the rate of flotation of various sizes of particles and …