Chemical Engineering Commons^™

On The Mesophase Formation Of 1,3-Dialkylimidazolium Ionic Liquids, Mei Yang, Bert Mallick, Anja V. Mudring

Anja V. Mudring

A series of seven different 1,3-dialkylimidazolium-based ion-pair salts with the same molecular weight and size but different symmetries was synthesized. For all salts, bromide was chosen as the counterion, giving the series ([CnIMCm][Br]), where IM = imidazolium and Cn and Cm are varying N-alkyl substituents with n + m = 13. Thus, the effect of symmetry on the physicochemical properties, such as thermal transitions, densities and viscosities and particularly mesophase formation, is investigated herein. All salts are fully characterized by NMR spectroscopy and mass spectrometry, and their physicochemical properties such as thermal transitions, densities, and viscosities are reported. Single crystal …

Structure, Stability, And Electronic Interactions Of Polyoxometalates On Functionalized Graphene Sheets, Jean-Philippe Tessonnier, Stephanie Goubert-Renaudin, Shaun Alia, Yushan Yan, Mark A. Barteau

Jean-Philippe Tessonnier

Polyoxometalates (H3PMo12O40, H 3PW12O40, H4PMo11VO 40) supported on oxygen- and alkyl-functionalized graphene sheets were investigated. Discrete molecular species were directly observed by electron microscopy at loadings below 20 wt.%. The interaction between the polyoxometalates and the graphene surface was found to significantly impact their vibrational spectra and a linear correlation between the frequency of the M-Oc-M vibration and the dispersion was evidenced by FTIR. While bulk-like electronic properties were observed for small aggregates (2-5 nm), UV-vis spectroscopy and cyclic voltammetry revealed changes in the electronic structure of isolated molecular species as a result of their interaction with graphene. Because of …

Novel Copper (Ii) Mediated Transfection Nano-Systems And Biological Properties Of Pyridinium Surfactants, Sarit Pal

Open Access Theses & Dissertations

Efficacy of gene therapy is relied upon the improvement of gene delivery vectors into mammalian cells. Although viral-based polynucleotide carriers are still considered as the most common method for gene delivery but the cost effectiveness, nonspecific lethal immune response has evoked the renaissance of non-viral synthetic delivery systems. An initial discovery by Felgnar et al showed Cationic Liposomes (CLs) (having an overall positive charge) when mixed with DNA to form CL-DNA complexes can enhance the transfer of polynucleotides into cells followed by its expression. Presently, a flurry of experimental works is taking place for the better understanding of structural characterization …

Characterization And Aerosol Dispersion Performance Of Spray-Dried Chemotherapeutic Pegylated Phospholipid Particles For Dry Powder Inhalation Delivery In Lung Cancer, Samantha A. Meenach, Kimberly W. Anderson, J. Zach Hilt, Ronald J. Mcgarry, Heidi M. Mansour

Chemical Engineering Faculty Publications

Pulmonary inhalation chemotherapeutic drug delivery offers many advantages for lung cancer patients in comparison to conventional systemic chemotherapy. Inhalable particles are advantageous in their ability to deliver drug deep in the lung by utilizing optimally sized particles and higher local drug dose delivery. In this work, spray-dried and co-spray dried inhalable lung surfactant-mimic PEGylated lipopolymers as microparticulate/nanoparticulate dry powders containing paclitaxel were rationally designed via organic solution advanced spray drying (no water) in closed-mode from dilute concentration feed solution. Dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylethanolamine poly(ethylene glycol) (DPPE-PEG) with varying PEG chain length were mixed with varying amounts of paclitaxel in methanol …

S-Stem Scholars, A Second Generation: Support For At-Risk Upper Division And Transfer Students In Ceas, Andrew A. Kline, Betsy M. Aller

Academic Leadership Academy

Begun in 2010, the S-STEM Scholar Program increases opportunities for financially needy but academically talented students. These students:

•Are first-time, first year students •Demonstrate financial need through FAFSA applications

•Will enter a major in the College of Engineering and Applied Sciences

•Have a math ACT of 24 or above

Student awardees receive up to $3,000 per semester, and continue to receive this amount for up to eight semesters with continued academic success and progress to degree.

Ultrasound For Improved Crystallisation In Food Processing, N. Misra, Navneet Deora, Brijesh Tiwari, Patrick Cullen

Articles

Within the food industry, controlling crystallisation is a key factor governing food structure, texture and consumer appeal, with some foods requiring the promotion of crystallisation in a controlled manner (e.g. chocolate) and others a check (e.g. in honey). Sonocrystallisation is the application of ultrasound energy to control the nucleation of a crystallisation process. The use of power ultrasound provides a non-invasive approach to producing crystals with desired properties. Sonocrystallisation facilitates process control, primarily by modulating crystal size distribution and morphology. This paper details the governing mechanisms of sonocrystallisation. Proven and potential applications of the process in foods, including chocolates, honey, …

The Critical Role Of Mechanism-Based Models For Understanding And Predicting Liposomal Drug Loading, Binding And Release Kinetics, Sweta Modi

Theses and Dissertations--Pharmacy

Liposomal delivery systems hold considerable promise for improvement of cancer therapy provided that critical formulation design criteria can be met. The main objective of the current project was to enable quality by design in the formulation of liposomal delivery systems by developing comprehensive, mechanism-based mathematical models of drug loading, binding and release kinetics that take into account not only the therapeutic requirement but the physicochemical properties of the drug, the bilayer membrane, and the intraliposomal microenvironment.

Membrane binding of the drug affects both drug loading and release from liposomes. The influence of bilayer composition and phase structure on the partitioning …

Cross-Plane Thermal Properties Of Transition Metal Dichalcogenides, Christopher Muratore, Vikas Varshney, Jaime J. Gengler, Jianjun Hu, John E. Bultman, Timothy M. Smith, Patrick J. Shamberger, Bo Qiu, Xiulin Ruan, Ajit K. Roy, Andrey A. Voevodin

Chemical and Materials Engineering Faculty Publications

In this work, we explore the thermal properties of hexagonal transition metal dichalcogenide compounds with different average atomic masses but equivalent microstructures. Thermal conductivity values of sputtered thin films were compared to bulk crystals. The comparison revealed a >10 fold reduction in thin film thermal conductivity. Structural analysis of the films revealed a turbostratic structure with domain sizes on the order of 5–10 nm. Estimates of phonon scattering lengths at domain boundaries based on computationally derived group velocities were consistent with the observed film microstructure, and accounted for the reduction in thermal conductivity compared to values for bulk crystals.

Characterization Of And Controlling Morphology Of Ultra-Thin Nanocomposites, Guy C. Laine

Theses and Dissertations--Chemical and Materials Engineering

Ultrathin film nanocomposites are becoming increasingly important for specialized performance of commercial coatings. Critical challenges for ultrathin film nanocomposites include their synthesis and characterization as well as their performance properties, including surface roughness, optical properties (haze, refractive index as examples), and mechanical properties. The objective of this work is to control the surface roughness of ultrathin film nanocomposites by changing the average particle size and the particle volume fraction (loading) of monomodal particle size distributions. This work evaluated one-layer and two-layer films for their surface properties. Monodispersed colloidal silica nanoparticles were incorporated into an acrylate-based monomer system as the model …

Drug Treatment Of Kidney Clip-Induced Hypertension In Rats; Peroxidase Tracer Spot Frequency In Rat Aorta After Chemically Induced Apoptosis, Simon Kleinbart

Dissertations and Theses

No abstract provided.

Photocrosslinked Methylcellulose Hydrogels For Controlled Protein Release, Das Dritiman

Dissertations and Theses

No abstract provided.

Doping Of Metal Organic Framework (Uio) And For N02 Adsorption At Ambient Conditions, Amani M. Ebrahim

Dissertations and Theses

Pollution issues and environmental concerns have led to the development of various air purification technologies. Nitrogen dioxide NO2 is one of the toxic gases in the atmosphere that is corrosive; it causes severe damage to materials, even at low concentrations. Research on the adsorption of this gas at atmospheric pressure and ambient temperatures is uncommon because of limited industrial applications. The thermal stability and microporous nature of Zirconium-based Metal Organic Framework (Zr-MOF) UiO-66 and UiO-67 make them good candidates for metal or amine decoration. The objective of this work was to investigate the effect of metal or amine doping (direct …

Potential For Electrical Power Generation Using Forest Wood Biomass In Rural Areas Of Catalonia, Arnau Gonzalez

Open Access Theses

Biomass is a renewable energy source that has been used for many years. However, its usage as an electricity source in Spain is not well developed due to many causes, among which highlights the lack of knowledge about the available technical potential. This research sought to close this gap assessing the technical potential for electricity generation using forest wood biomass in rural areas of Catalonia. The study characterizes the amount and type of biomass available in Catalonian forests that can be used to produce electricity without going beyond the capacity of regeneration of the forest, as well as the state-of-the-art …

Solution Combustion Synthesis Of Cobalt Oxide For Use As A Catalyst Precursor In The Hydrolysis Of Sodium Borohydride, Teandra Leigh Pfeil

Open Access Theses

Solution combustion synthesized (SCS) cobalt oxide (Co₃O₄) powder has been studied as a catalyst precursor for the hydrolysis of sodium borohydride (NaBH₄). Synthesis is completed in less than two minutes and results indicate SCS is capable of reproducibly synthesizing 98.5-99.5% pure Co₃O₄ nano-foam materials. SCS materials demonstrate an as-synthesized specific surface area of 24 m²/g, a crystallite size of 15.5 nm, and fine surface structures on the order of 4 nm. Despite having similar initial surface areas and sample purities, SCS-Co₃O₄ outperforms commercially available Co_{3 …}

One Dimensional Stochastic Coating Growth Kinetics Of Peg 3400 Onto Ammonium Nitrate In A Fluidized Bed, Brandon Smeltzer

USF Tampa Graduate Theses and Dissertations

Fluidized beds represent a cost effective, scalable technology invaluable to the chemical processing community as part of the global scheme of particle design. However, despite wide spread use and multiple approaches (empirical and mechanistic) to modeling a fluidized bed coating process, operations must be done at different scales due to changes within the balance of phenomenological forces (e.g. gravity, buoyancy, drag, surface tension, viscosity, kinetic energy).

Ammonium nitrate is synthetic compound that has multiple applications such as fertilizer, rocket fuel, and self-cooling applications. Ammonium nitrate has five temperature dependent crystal structures that are accompanied by a change in density. The …

Structured Materials For Catalytic And Sensing Applications, Selma Hokenek

USF Tampa Graduate Theses and Dissertations

The optical and chemical properties of the materials used in catalytic and sensing applications directly determine the characteristics of the resultant catalyst or sensor. It is well known that a catalyst needs to have high activity, selectivity, and stability to be viable in an industrial setting. The hydrogenation activity of palladium catalysts is known to be excellent, but the industrial applications are limited by the cost of obtaining catalyst in amounts large enough to make their use economical. As a result, alloying palladium with a cheaper, more widely available metal while maintaining the high catalytic activity seen in monometallic catalysts …

Theoretical Studies Of Co Based Catalysts On Co Hydrogenation And Oxidation, Nianthrini Balakrishnan

USF Tampa Graduate Theses and Dissertations

CO hydrogenation and CO oxidation are two important processes addressing the energy and environmental issues of great interest. Both processes are carried out using metallic catalysts. The objective of this dissertation is to study the catalytic processes that govern these two reactions from a molecular perspective using quantum mechanical calculations. Density Functional Theory (DFT) has proven to be a valuable tool to study adsorption, dissociation, chain growth, reaction pathways etc., on well-defined surfaces. DFT was used to study the CO reduction reactions on promoted cobalt catalyst surfaces and CO oxidation mechanisms on cobalt surfaces.

CO hydrogenation via Fischer-Tropsch Synthesis (FTS) …

Comparison Of Class Ii Injection Well Area Of Review Requirements With Area Of Evaluation For Hydraulically Fractured Wells, Yashesh Jitendra Panchal

Masters Theses

"Since 2010 the US Environmental Protection Agency (EPA) has been proposing plans to study, and has now initiated research regarding the potential impact of hydraulic fracturing processes on drinking water sources. Their work refers to an 'Area of Evaluation' around a hydraulically fractured well, inferring that the wells immediately around hydraulic fractured wells should be studied, to evaluate the conditions of these wells and their potential to contaminate overlying USDWs. Class II injection wells must have a minimum 1/4 mile radius area of review to determine the condition of wells surrounding the proposed injection well. All wells within this AOR …

Peg-Phosphorylcholine Hydrogels As Tunable And Versatile Platforms For Mechanobiology, William G. Herrick, Thuy V. Nguyen, Marianne Sleiman, Samantha Mcrae, Todd Emrick, Shelly Peyton

Chemical Engineering Faculty Publication Series

We report here the synthesis of a new class of hydrogels with an extremely wide range of mechanical properties suitable for cell studies. Mechanobiology has emerged as an important field in bioengineering, in part due to the development of synthetic polymer gels and fibrous protein biomaterials to control and quantify how cells sense and respond to mechanical forces in their microenvironment. To address the problem of limited availability of biomaterials, in terms of both mechanical range and optical clarity, we have prepared hydrogels that combine poly(ethylene glycol) (PEG) and phosphorylcholine (PC) zwitterions. Our goal was to create a hydrogel platform …

Multi-Scale Characterization Of Nanostructured Sodium Aluminum Hydride, Shathabish Narasegowda

Doctoral Dissertations

Complex metal hydrides are the most promising candidate materials for onboard hydrogen storage. The practicality of this class of materials is counter-poised on three critical attributes: reversible hydrogen storage capacity, high hydrogen uptake/release kinetics, and favorable hydrogen uptake/release thermodynamics. While a majority of modern metallic hydrides that are being considered are those that meet the criteria of high theoretical storage capacity, the challenges lie in addressing poor kinetics, thermodynamics, and reversibility. One emerging strategy to resolve these issues is via nanostructuring or nano-confinement of complex hydrides. By down-sizing and scaffolding them to retain their nano-dimensions, these materials are expected to …