Thesis (Ph. D.)--Georgia State University, 2007. / Title from file title page. Phang C. Tai, committee chair; John Houghton Parjit Kaur, Chung-Dar Lu, committee members. Electronic text (148 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed Dec. 7, 2007. Includes bibliographical references (p. 125-140).

Poly (vinylidene fluoride) (PVDF-beta) nanoporous membranes Were Made by Chemical Revealing tracks of swift heavy ion induced from irradiation. Pore opening and Varied radiican Be In A Manner controllable with the etching time. Nanopore size in nanometer scale (from 12 nm to 50 nm) appears to be linearly dependent to the etching time. Then It Was Necessary to the characterization tools adapted to thesis membranes. Consequently, we resorted to the use of structural analysis methods (Scanning Electron Microscopy, Small Angle Neutron Scattering) Developed and evaluation methods of the membrane transport properties like ionic gas permeation and di? Usion. Obtenues results conrm the pore opening (break through) and hydrophobicity of the material, Which We Have modi? Ed with hydrophilic molecules. In this precise case, grafting of the acrylic acid Was Initiated by Still Remains the radicals after track-etching (Called radio grafting). This key result by obtenues Was A Study of Electron Paramagnetic Resonance. The labeling of chemical Functionalities Introduced with fluorescent probes Was a very effective mean to visualize very few "Amount of molecules by confocal microscopy. The radiografting autrement specically localized inside etched tracks. The protocol others to create The Possibility Functionality has double, the one localized inside the nanopores and the Other is the surface of membranes. The modication of radiation grafting parameters (the acrylic acid concentration, solvent nature, use of transfer agent) and the chemical properties of the nanopore walls Have a direct impact on the transportation Pure compression. Key Words: beta-PVDF, track-etching, nanopores, radicals, radiografting, selective functionalisation, Small Angle Neutron Scattering, Confocal Laser Scanning Microscopy.

Graduation date: 1995

Graduation date: 1994

Thesis (Ph. D.) -- Virginia Commonwealth University, 2006. / Prepared for: Dept. of Chemistry. Bibliography: leaves 165-175. Also available online via the Internet.

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

Thesis (Ph. D.)--Ohio State University, 2006. / Available online via OhioLINK's ETD Center; full text release delayed at author's request until 2007 Sep 11

Isoelectric focusing is one of the most important techniques in protein separations. Preparative-scale isoelectric separations often use buffering membranes (isoelectric membranes), but there are no good known methods for the characterization of their pI values. Therefore, UV-absorbing carrier ampholyte mixtures (UVCAs) have been synthesized, analytically characterized, and utilized for the characterization of the pI value of a buffering membrane. To synthesize the UVCAs, addition of a UV-absorbing electrophile, 3-phenoxypropyl bromide (PhOPrBr), to a pentaethylenehexamine (PEHA) carrier ampholyte backbone, resulted in an intermediate that was subsequently reacted with increasing amounts of acrylic acid (up to 8 equiv) and itaconic acid (up to 2 equiv) via Michael’s addition. The intermediates and final products were characterized by 1H-NMR and full-column imaging capillary isoelectric focusing techniques. An optimal blended mixture of selected UVCAs was first desalted and purified by isoelectric trapping and its composition verified by full-column imaging isoelectric focusing. The mixture of UVCAs possessed a broad pI distribution from approximately pH 3 – 10. By isoelectric trapping, the mixture was separated into two subfractions with a polyacrylamide-based isoelectric membrane of known pI as the separation membrane and poly(vinyl) alcohol-based buffering membranes as the restriction membranes. The pI of the most basic UV-active carrier ampholyte in the anodic fraction was determined to be 4.4 and the pI of the most acidic UV-active carrier ampholyte in the cathodic fraction was determined to be 4.4, confirming that the pH of the polyacrylamide-based isoelectric membrane was pH 4.4.

No description available.

Produced water and spent drilling fluids from petroleum operations represent a significant expense to companies developing new energy reserves. These spent fluids, seldom recycled, offer a viable source of water resources for oil-field reuse. A major obstacle to reuse is the presence of suspended solid material in the fluids. Such contaminants, if not removed, will not only prevent any reuse but will also impede disposal. The objective of this project was to evaluate membrane filtration as a way to remove suspended and entrained particles to produce re-useable effluents using membranes. Ceramic and Polyvinylidene Flouride (PVDF) hollow fibre membranes were used in laboratory scale experiments in the investigation of the colloidal filtration of field produced spent drilling fluids and produced water. Feed parameter and operational parameter evaluation of ceramic and PVDF hollow fibre membrane filtration of spent drilling fluids and produced water showed that feed concentration, solids in the spent drilling fluid and oil in the produced water, is the most important parameter during membrane filtration. Operational parameter variation showed that high cross flow velocity was beneficial in flux maintenance during spent drilling fluid filtration due to its high solids concentration because of the scouring effect on the cake layer on the membrane surface. Pressure regimens were important in flux decline as relatively high pressures accelerate the consolidation of the concentration polarization layer causing flux decline. High temperatures were generally beneficial for increased flux in the filtration of produced water and spent drilling fluids. Resistance calculations were used to deduce the contribution of individual resistances during the ceramic filtration of produced water and spent drilling fluids and were identified as a real-time tool for monitoring membrane integrity and fouling. Backwashing as a fouling mitigation technique was effective in flux maintenance in ceramic membranes especially in the filtration of produced water; cleaning solutions were effective in flux recovery in ceramic membrane filtration and to a slightly lesser degree in hollow fibre membrane filtration. A methodology in determining the suitability of water based oil field wastes using membranes was developed to help future investigations of this type.