Chemical Engineering Commons^™

Wear Resistant And Biocompatible Coatings For Medical Devices And Method Of Fabrication, Mary Gilliam, Susan Farhat, Ali Zand

Chemical Engineering Patents

Abstract: A method of forming a biocompatible or biologically inert article for use in an application in which the article will make contact with at least one tissue, organ, or fluid within a human or animal body is provided. The method generally comprises providing an article having an external sur face; selecting chemical precursors; using a means to direct one or more chemical precursors towards or to apply such chemical precursors to the ex ternal surface; activating the chemical precursors by exposing said precursors to atmospheric pressure plasma; and grafting and/or cross-linking the chem ical precursors to form a solid …

Particle Dispersion In Homogeneous Turbulence Using The One-Dimensional Turbulence Model, Guangyuan Sun, David O. Lignell, John C. Hewson, Craig R. Gin

Faculty Publications

Lagrangian particle dispersion is studied using the one-dimensional turbulence (ODT) model in homogeneous decaying turbulence configurations. The ODT model has been widely and successfully applied to a number of reacting and nonreacting flow configurations, but only limited application has been made to multiphase flows. Here, we present a version of the particle implementation and interaction with the stochastic and instantaneous ODT eddy events. The model is characterized by comparison to experimental data of particle dispersion for a range of intrinsic particle time scales and body forces. Particle dispersion, velocity, and integral time scale results are presented. The particle implementation introduces …

Atomic Layer Deposition Of High Quality Hfo2 Using In-Situ Formed Hydrophilic Oxide As An Interfacial Layer, Lei Han, Jie Pan, Qinglin Zhang, Shibin Li, Zhi Chen

Electrical and Computer Engineering Faculty Publications

High-quality HfO₂ cannot be grown directly on Si substrate using atomic layer deposition (ALD), and an interfacial oxide layer is needed. Traditionally, interfacial oxide layer is formed either in SC1 solution (2 NH₄OH: 4 H₂O₂: 200 H₂O) or by ozonated water spraying. A highly hydrophilic SiO₂ interfacial layer was in-situ formed in the ALD chamber using 1 cycle of ozone and water. The HfO₂ deposited on this interfacial layer showed great growth linearity. The gate leakage current is comparable to that formed using chemical oxide as the interfacial layer. …

Investigation And Modeling Of Uranium Polarization For The Electrorefining Of Scrap U-Mo Foils, Melissa Rose

Open Access Dissertations

A uranium molybdenum alloy fuel has been proposed to convert research and test reactors from highly enriched uranium to low enriched uranium to increase the proliferation resistance at such reactors. Pyroprocessing has been selected to recover uranium from the scrap produced in the manufacture of this novel fuel type. Electrorefining, the main separation process of pyroprocessing, is modeled through a novel approach using corrosion theory. To use corrosion theory, knowledge of uranium polarization and kinetic parameters such as Tafel constant, transfer coefficient and exchange current density are required. Uranium polarization was investigated at five temperatures and three scan rates in …

Computational Study Of Sodium Magnesium Hydride For Hydrogen Storage Applications, Fernando Antonio Soto Valle

Doctoral Dissertations

Hydrogen offers considerable potential benefits as an energy carrier. However, safe and convenient storage of hydrogen is one of the biggest challenges to be resolved in the near future. Sodium magnesium hydride (NaMgH 3) has attracted attention as a hydrogen storage material due to its light weight and high volumetric hydrogen density of 88 kg/m3. Despite the advantages, hydrogen release in this material occurs at approximately 670 K, which is well above the operable range for on-board hydrogen storage applications. In this regard, hydrogen release may be facilitated by substitution doping of transition-metals. This dissertation describes first-principles computational methods that …

Identifying Conditions To Optimize Lactic Acid Production From Food Waste, Raymond M. Redcorn

Open Access Theses

There is an increased demand for lactic acid for the production of biopolymers and to aid nutrient removal in wastewater treatment. Food waste offers a source of soluble sugars to produce lactic acid, which does not increase land demand, but digestion conditions have yet to be optimized when co-digested with primary sludge. Food waste was collected from cafeteria waste bins, homogenized and seeded with primary sludge. A Box Behnken Response surface design was used to optimize lactic acid production based on pH, temperature, loading rate, and retention time. Subsequent experiments verified and refined those conditions to optimize for both yield …

Computational Fluid Dynamics Analysis Of Freeze Drying Process And Equipment, Nikhil P. Varma

Open Access Theses

Freeze drying is an important, but expensive, inefficient and time consuming process in the pharmaceutical, chemical and food processing industries. Computational techniques could be a very effective tool in predictive design and analysis of both freeze drying process and equipment. This work is an attempt at using Computational Fluid Dynamics(CFD) and numerical simulations as a tool for freeze drying process and equipment design.

Pressure control is critical in freeze dryers, keeping in view the product stability. In industrial freeze dryers, loss of pressure control can lead to loss of an entire batch. Pressure variation within the chamber could also lead …

Impact Of Nanostructure On Polymer-Based Nonvolatile Memory Devices, Seung Hyun Sung

Open Access Theses

Memory functionality is essential for many high-end electronic applications (e.g. , smart phones, personal computers). Particularly, organic nonvolatile memory devices based on polymer ferroelectric materials are a promising approach toward the development of low-cost memory due to the ease of processing and flexibility associated with the device. Here, we will focus on a memory device with a two-component active layer and a diode structure. This ferroelectric diode (FeD) has a nanostructured active layer, composed of ferroelectric and semiconducting polymers, and it can provide easy access to high-performance polymer-based memory devices. In order to create these nanostructured active layers, we …

Tools For Efficient Design Of Multicomponent Separation Processes, Joshua Lee Huff

Open Access Dissertations

Separations account for as much as 85% of plant operating costs in chemical production; it is therefore important that they be designed with energy efficiency in mind. This can only be achieved if two things are achieved: the complete space of design options is known, and an accurate way is developed to compare all possible design options. For both membrane separation cascades and multicomponent distillation configurations, this dissertation explores methods for designing energy efficient separations.^ The operating cost of membranes used in production of nitrogen gas from air is largely driven by the compressors required to maintain a pressure differential. …

Structure And Activity Relationships Of Bimetallic Catalysts For Aqueous Phase Reforming And The Water-Gas Shift Reaction, Fred Gerald Sollberger

Open Access Dissertations

As the existing deposits of petroleum and non-renewable energy resources are exhausted, become more difficult to extract, and remain in politically unstable regions of the world, the search for long term alternatives for fuels and chemicals from renewable sources such as biomass continues. One promising process for the production of renewable hydrogen to use in conversion of biomass to fuels and chemicals is aqueous phase reforming (APR) of cellulose-derived carbohydrates. In the first study Pt/MWCNT catalysts have been promoted by addition of transition metal promoters Cu, Ni, Co, Fe, Mn, Mo, W, and Re in Pt:M 1:1 atomic ratios to …

Dynamics Of Nanoparticles In Fluids And At Interfaces, Weikang Chen

Dissertations, Theses, and Capstone Projects

In this thesis, we use molecular dynamics simulation to study three basic behaviors or properties of nanoparticles: deposition during droplets evaporation, slip boundary condition and Brownian motion. These three problems address the need for an in-depth understanding of the dynamics of nanoparticles in fluids and at interfaces. In the first problem, evaporation of the droplets dispersed with particles, we investigated the distribution of evaporative flux, inner flow field, density and temperature. And we use these numerical experiments to check on our hydrodynamic theory of the "coffee ring" phenomenon. The simulations reveal the connection between the particle interactions and the deposit …

Development Of Ultrasound Sensitive Eliposomes Containing Doxorubicin For Drug Delivery, Chung-Yin Lin, William G. Pitt, Kuo-Chen Wei

Faculty Publications

Aims: A novel nanocarrier was formulated by remote loading of doxorubicin (Dox) into a dipalmitoylphosphatidylcholine (DPPC) liposome that also contains various perfluorocarbon (PFC) droplets within its aqueous interior. It was shown that Dox can be loaded to a level of up to 67% into these large unilamellar vesicles composed of DPPC and cholesterol by employing a transmembrane pH gradient technique.

Methods: The different encapsulation efficiencies for these eLipoDox constructs of differing PFC composition are 45.5% (PFC5), 31.5% (PFC6) and 66.7% (PFC5/PFC6 mixture, PFCm). At 30 seconds of insonation, the eLipoDox formulation with PFCm droplets appeared to release more Dox than …

Study Of Polyaniline For Use In An Organic Field Effect Transistor, Thomas Martin Sprinkle

Chemistry & Biochemistry Theses & Dissertations

Polyaniline's emeraldine base form was synthesized via chemical polymerization in HCl acidic media utilizing ammonium persulfate as the oxidant. Synthesis was done at room temperature and -30 'C and characterized for differences by X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry. Methanol soxhlet extraction was done to increase number average molecular weight from 77,400 to 81,000 and decrease the poly dispersity index from 3.82 to 2.14. Films were cast using N, N'- Dimethylpropyleneurea and N-Methylpyrrolidone and showed poor mechanical properties upon acidic doping.

Cyclic voltammetry was done with HC1 as the acidic media and an ITO coated slide as the …

Investigating The Stability Of Eliposomes At Elevated Temperatures, Ghaleb A. Husseini, William G. Pitt, Marjan Javadi

Faculty Publications

eLiposomes encapsulate a perfluorocarbon nanoemulsion droplet inside a liposome. Ultrasound is then used as a trigger mechanism to vaporize the perfluorocarbon, break the liposome, and release the desired drug to the tumor tissue. The purpose of this research is to show that eLiposomes synthesized using perfluoropentane are stable above the normal boiling point of the perfluoropentane and at body temperature and thus has potential for use in vivo. Experiments involving the release of fluorescent calcein molecules were performed on eLiposomes to measure the release of calcein at various temperatures in the absence of ultrasound. Results showed that eLiposomes are stable …

Investigating The Stability Of Eliposomes At Elevated Temperatures, Ghaleb A. Husseini, William G. Pitt, Marjan Javadi

Faculty Publications

eLiposomes encapsulate a perfluorocarbon nanoemulsion droplet inside a liposome. Ultrasound is then used as a trigger mechanism to vaporize the perfluorocarbon, break the liposome, and release the desired drug to the tumor tissue. The purpose of this research is to show that eLiposomes synthesized using perfluoropentane are stable above the normal boiling point of the perfluoropentane and at body temperature and thus has potential for use in vivo. Experiments involving the release of fluorescent calcein molecules were performed on eLiposomes to measure the release of calcein at various temperatures in the absence of ultrasound. Results showed that eLiposomes are stable …

Liquid Metal Electrodes For Rechargeable Batteries, Rutooj Deshpande, Juchuan Li, Yang-Tse Cheng

Chemical and Materials Engineering Faculty Patents

An electrode for a lithium ion battery includes a liquid metal having a melting point that is below the operating temperature of the battery, which transforms from a liquid to a solid during lithiation, and wherein the liquid metal transforms from a solid to a liquid during delithiation.

Use Of Blood Oxygenator Membrane Units In Teaching Mass Balances, Friction Factor And Mass Transfer Analysis, Keith Mciver

Theses and Dissertations

Many applications of chemical engineering principles are biomedical but traditional chemical engineering education does not focus on these applications. New laboratory experiments with hollow fiber blood oxygenators allow integration of concepts into already full programs. This work describes three new educational experiments that have been developed to introduce students to concepts of mass balances, mass transfer and momentum transfer as applied to a hollow fiber blood oxygenator. In addition, a new mass transfer correlation is presented for the Medtronic Affinity NT blood oxygenator, which has not been reported previously in the literature. Mass transfer of oxygen through the hollow fiber …

Method And Apparatus For Surface Chemical Functionalization Of Powders And Nanoparticles, Mary Gilliam, Susan Farhat, Graham Garner, Michael Magyar

Chemical Engineering Patents

A method and apparatus is provided for the modification of the surface chemistry of solid nano- and micro-particles in order to tailor the properties and functions of these particles. The method generally involves the generation of an atmospheric plasma glow discharge and energetic species that undergo chemical reaction with the surface of the primary particles. The process includes the generation of energetic species to initiate reaction, optional delivery of a precursor fluid, optional delivery of chemical species for grafting, and delivery of separated and de-agglomerated particles into the plasma discharge exiting the plasma generation chamber.

Development Of Experiments Involving Pharmaceutical Manufacturing Principles, Alexander Struck Jannini

Theses and Dissertations

Laboratory experiments were developed to incorporate pharmaceutical engineering concepts into Freshman-level engineering courses. The goal is to increase the interest of pharmaceutical engineering in students and provide the necessary background for more advanced courses in the field. The experiments can be used on an individual basis, or to be grouped into themes for more focused learning objectives. The laboratory experiments are available at the pharmaceutical knowledge and training website www.PharmaHUB.org under the Teaching Resources tab.

Spatial Stochastic Modeling Of The Erbb Receptor Family, Meghan Pryor

Chemical and Biological Engineering ETDs

ErbB transmembrane receptors are a family of 4 receptor tyrosine kinases that interact with one another through homo and heterodimer interactions. When these dimers form, the kinase domains on the receptor tails interact with one another, transphosphorylating one another, initiating a signal cascade. The signaling pathways these receptors participate in are responsible for many different cell functions including apoptosis, growth, and proliferation. The overexpression of these receptors has been linked to various forms of cancer, emphasizing the importance of understanding how these receptors interact with one another to trigger these cascades. Single Particle Tracking experiments have provided more precise and …