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Sodium-Initiated Polymerization Of Alpha-Methylstyrene In The Vicinity Of Its Reported Ceiling Temperature, Shuenn-Long Ou

Dissertations

No abstract provided.

Distributed Parameter Sensitivity Theory To Solve Certain Reliability Problems, Moses Nee Buernor Ayiku

Dissertations

It is well known that in actual control systems there are uncontrolled parameter changes caused by aging of elements, temperature, pressure and effects of externalmedium, among others, which may impair the performance ofthe system. Hence, there is the need to develop systems that weakly react to these parameter fluctuations. Sensitivity theory has been developed to study some of these problems. Most of the investigations in this area, however, deal with problems in continuous systems modeled by ordinary differential equations. Even the recent publications on sensitivity problems in distributed parameter control systems are largely concerned with systems modeled by first order …

Preparation And Magnetic Properties Of Rare Earth Garnets And Apatites, Rostam Mondegarian

Dissertations

It has been found possible to prepare garnets with magnetic trivalent rare earth ions filling all or most dodecahedral sites while nonmagnetic Sc³⁺ ions fill all octahedral sites and magnetic Fe³⁺ ions fill all or most tetrahedral sites. Phase-pure garnets found include {RE_3-ySc_y}[Sc₂](Fe₃)O₁₂, where RE is Sm, Eu, Gd, Tb or Dy and y can be zero with Sm and Eu; {Nd₃}[Sc₂](Fe_zGa_3-z)O₁₂; and other Nd-Sc-Fe garnets of the type {Nd_3-(w+y)M_wS_cy}[Sc₂](Fe …

Separations Of Multicomponent Mixtures Via Thermal Parametric Pumping, John Daniel Stokes

Dissertations

This dissertation covers the separation of solutes from multicomponent solutions via direct mode thermal parametric pumping.

Dilute solution separations were predicted from existing binary equations by assuming the existence of pseudo binary systems, each system consisting of one solute and the common solvent. Two systems, toluene-aniline-n-heptane and toluene-acetophenone-n-heptane with a silica gel adsorbent were used to experimentally demonstrate the separation. Experimental results were in good agreement with the mathematical predictions.

For concentrated multicomponent solutions, the separation was demonstrated by the system, toluene-acetophenone-n-heptane on silica gel. The effects of mass transfer and nonlinear adsorption isotherms became significant and a numerical solution …