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Full-Text Articles in Engineering
Nanostructured Metal Thin Films As Components Of Composite Membranes For Separations And Catalysis, Michael J. Detisch
Nanostructured Metal Thin Films As Components Of Composite Membranes For Separations And Catalysis, Michael J. Detisch
Theses and Dissertations--Chemical and Materials Engineering
Novel metallic thin film composite membranes are synthesized and evaluated in this work for improved separations and catalysis capabilities. Advances in technology that allow for improved membrane performance in solvent separations are desirable for low molecular weight organic separation applications such as those in pharmaceutical industries. Additionally, the introduction of catalytic materials into membrane systems allow for optimization of complex processes in a single step. By adding a nanostructured metallic thin film to its surface, a polymer membrane may be modified to exhibit these improved properties. Using magnetron sputtering, thin metal films may be deposited on commercially available membranes to …
Mixed Surfactant Systems: Thermodynamics And Applications In Metal Oxide Imprinting, Suvid Joshi
Mixed Surfactant Systems: Thermodynamics And Applications In Metal Oxide Imprinting, Suvid Joshi
Theses and Dissertations--Chemical and Materials Engineering
In this work we study mixtures of cationic surfactant (CTAB) and sugar based surfactant(s) (octyl beta-D-glucopyranoside (C8G1), dodecyl maltoside (C12G2) and octyl beta-D-xylopyranoside (C8X1)) to understand the non-ideal thermodynamic behavior of the mixtures of cationic and non-ionic surfactants in water and synthesis of imprinted materials. The thermodynamics of micellization, mixing and dilution of these systems are studied using Isothermal Titration Calorimetry (ITC) and the experimental data obtained are modeled with a pseudo-phase separation model with non-ideal mixing described by regular solution theory. It is shown that a model accounting for enthalpy of demicellization and enthalpy of dilution based on McMillan-Mayer …
Structure And Catalytic Properties Of Ultra-Small Ceria Nanoparticles, Xing Huang
Structure And Catalytic Properties Of Ultra-Small Ceria Nanoparticles, Xing Huang
Theses and Dissertations--Chemical and Materials Engineering
Cerium dioxide (ceria) is an excellent catalytic material due to its ability to both facilitate oxidation/reduction reactions as well as store/release oxygen as an oxygen buffer. The traditional approach to assess and improve ceria's catalytic behavior focuses on how efficiently O-vacancies can be generated and/or annihilated within the material, and how to extend established understandings of "bulk" ceria to further explain the greatly enhanced catalytic behavior of ultra-small ceria nanoparticles (uCNPs) with sizes less than 10 nm. Here, using density functional theory (DFT) calculations, we reexamine the atomic and electronic structures of uCNPs, especially their surface configurations. A unique picture …
Precise Control Of Carbon Nanotube Membrane Structure For Enzyme Mimetic Catalysis, Nicholas W. Linck
Precise Control Of Carbon Nanotube Membrane Structure For Enzyme Mimetic Catalysis, Nicholas W. Linck
Theses and Dissertations--Chemical and Materials Engineering
The ability to fabricate a charge-driven water pump is a crucial step toward mimicking the catalytic ability of natural enzyme systems. The first step towards making this water pump a reality is the ability to make a carbon nanotube (CNT) membrane with uniform, 0.8 nm pore diameter. Proposed in this work is a method for synthesizing these carbon nanotubes via VPI-5 zeolite templated, transition metal catalyzed pyrolysis. Using a membrane composed of these CNTs, it is possible to get water molecules to flow single file at a high flow rate, and to orient them in such a way that would …