Chemical Engineering Commons^™

Structure, Rheology And Optical Properties Of Plasmonic Fluids, Tao Cong

Dissertations - ALL

Fluids with tunable optical and rheological properties are of fundamental and practical interest. They can be easily processed to manufacture thin films and interfaces for applications such as molecular detection and light trapping in photovoltaics. Cationic surfactants such as cetyl-trimethylammonium bromide have the ability to self assemble with metallic nanoparticles to form a corona or a double-layer vesicular structure. These structures upon further interaction with wormlike micelle fragments are hypothesized to form micelle-nanoparticle elastic networks. In this dissertation, solution phase self-assembly is utilized to uniformly distribute various metallic nanoparticles to produce stable multicomponent plasmonic fluids with remarkable color uniformity. The …

Tin Sensitization For Electroless Plating, Xingfei Wei

Graduate Theses and Dissertations

The tin sensitization process has been used in electroless plating since 1940s Brenner and Riddell developed the electroless plating for surface metallization method. It was found to be an interesting topic to study tin sensitization for chemically controlling metal deposition on different substrates, because the tin sensitization process had critical effects on the electroless plated metal thin films. Nowadays electroless plating metal deposition is still an important method for depositing metals. It has a few advantages over the vapor deposition and electrodeposition method, such as work in an ambient condition, on nonconductive substrates, and without extra power input. Applying electroless …

An Experimental And Computational Evaluation Of The Importance Of Molecular Diffusion In Gas Gravity Currents, Jeremy Jac Herman

Graduate Theses and Dissertations

The accidental release of hazardous, denser-than-air gases during their transport or manufacture is a vital area of study for process safety researchers. This project examines the importance of molecular diffusion on the developing concentration field of a gas gravity current released into a calm environment. Questions which arose from the unexpectedly severe explosion in 2005 at Buncefield, England were of particular interest. The accidental overfilling of a large tank with gasoline on a completely calm morning led to a massive open air explosion. Forensic evidence showed that at the time of ignition, a vapor cloud, most of which now appears …

In-Situ Study Of E-Beam Al And Hf Metal Deposition On Native Oxide Inp (100), H. Dong, Santosh Kc, A. Azcatl, W. Cabrera, X. Qin, B. Brennan, D. Zhernokletov, K. Cho, R. Wallace

Faculty Publications

The interfacial chemistry of thin Al (∼3 nm) and Hf (∼2 nm) metal films deposited by electron beam (e-beam) evaporation on native oxide InP (100) samples at room temperature and after annealing has been studied by in situ angle resolved X-ray photoelectron spectroscopy and low energy ion scattering spectroscopy. The In-oxides are completely scavenged forming In-In/In-(Al/Hf) bonding after Al and Hf metal deposition. The P-oxide concentration is significantly decreased, and the P-oxide chemical states have been changed to more P-rich oxides upon metal deposition. Indium diffusion through these metals before and after annealing at 250 °C has also been characterized. …

Binding, Transcytosis And Biodistribution Of Anti-Pecam-1 Iron Oxide Nanoparticles For Brain-Targeted Delivery, Mo Dan, David B. Cochran, Robert A. Yokel, Thomas D. Dziubla

Pharmaceutical Sciences Faculty Publications

OBJECTIVE: Characterize the flux of platelet-endothelial cell adhesion molecule (PECAM-1) antibody-coated superparamagnetic iron oxide nanoparticles (IONPs) across the blood-brain barrier (BBB) and its biodistribution in vitro and in vivo.

METHODS: Anti-PECAM-1 IONPs and IgG IONPs were prepared and characterized in house. The binding affinity of these nanoparticles was investigated using human cortical microvascular endothelial cells (hCMEC/D3). Flux assays were performed using a hCMEC/D3 BBB model. To test their immunospecificity index and biodistribution, nanoparticles were given to Sprague Dawley rats by intra-carotid infusion. The capillary depletion method was used to elucidate their distribution between the BBB and brain parenchyma.

RESULTS: Anti-PECAM-1 …

Novel Liposomes For Targeted Delivery Of Drugs And Plasmids, Marjan Javadi

Theses and Dissertations

People receiving chemotherapy not only suffer from side effects of therapeutics but also must buy expensive drugs. Targeted drug and gene delivery directed to specific tumor-cells is one way to reduce the side effect of drugs and use less amount of therapeutics. In this research, two novel liposomal nanocarriers were developed. This nanocarrier, called an eLiposome, is basically one or more emulsion droplets inside a liposome. Emulsion droplets are made of perfluorocarbons which usually have a high vapor pressure. Calcein (as a model drug) and Paclitaxel were used to demonstrate drug delivery, and plasmids and siRNA were used to exemplify …

Compounds And Methods For Reducing The Occurrence Of Post-Surgical Adhesions, Thomas Dziubla, Eugene Kaplan, John Mark Medley Jr.

Chemical and Materials Engineering Faculty Patents

Compounds and methods for reducing the occurrence of a post-surgical adhesion are provided. The compounds can include acrylic acid groups and ethylene glycol groups, and can be directed to an area of damaged tissue by the incorporation of a fibrin targeting peptide. The compounds can further include a brush-like portion, capable of creating a steric barrier between a damaged tissue or organ and adjacent tissues or organs, and a targeting portion, capable of directing the compounds to a damaged tissue or organ. Methods of detecting damaged tissue and kits are also provided.

Metallic And Ceramic Thin Film Thermocouples For Gas Turbine Engines, Ian M. Tougas, Martin Amani, Otto J. Gregory

Chemical, Biomolecular, and Materials Engineering Faculty Publications

Temperatures of hot section components in today’s gas turbine engines reach as high as 1,500 °C, making in situ monitoring of the severe temperature gradients within the engine rather difficult. Therefore, there is a need to develop instrumentation (i.e., thermocouples and strain gauges) for these turbine engines that can survive these harsh environments. Refractory metal and ceramic thin film thermocouples are well suited for this task since they have excellent chemical and electrical stability at high temperatures in oxidizing atmospheres, they are compatible with thermal barrier coatings commonly employed in today’s engines, they have greater sensitivity than conventional …

Biocompatibility Of Cao-Na2o-Sio2/Tio2 Glass Ceramic Scaffolds For Orthopaedic Applications, A. W. Wren, A. Coughlan, K. E. Smale, S. T. Misture, B. P. Mahon, O. M. Clarkin, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

This work aims to determine the effect of substituting TiO₂ for SiO₂ in a 0.62SiO₂-Na₂O-0.24CaO based glass-ceramic scaffold. High temperature X-ray Diffraction (HT-XRD) was used to determine the sintering temperature (700oC). Both optical microscopy and x-ray micotomography was used to determine the average pore size (540-680ìm) of each scaffold. Cytocompatibility of each scaffold was conducted using murine mesenchymal stem cells. © 2013 IEEE.

Gallium Containing Glass Polyalkenoate Bone Cements: Ion Release And E. Coli Inhibition, L. Placek, A. W. Wren, A. Coughlan, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Glass Polyalkenoate Cement (GPC) series (LCon., LGa-1 and LGa-2) containing gallium (Ga) and a 50 wt% addition of E11 polyacrylic acid (PAA), previously developed, was evaluated for ion release, specifically Si, Ca, Zn and Ga, and E. coli inhibition. The maximum inhibition was observed in the t = 0 samples and was 0.35 mm for LCon. and 0.65 mm for LGa-1 and LGa-2. © 2013 IEEE.

An Investigation Into The Structure And Properties Of Cao-Zno-Sio 2-Tio2-Na2o Bioactive Glass/Hydroxyapatite Composite, Chokchai Yatongchai, Mark R. Towler, Anthony W. Wren

Chemical and Biochemical Engineering Faculty Research & Creative Works

Effect of the addition of CaO-ZnO-SiO₂-TiO₂-Na₂O glass as a reinforcing phase on properties of hydroxyapatite/glass composites was investigated. The addition of the glass caused the decomposition of HA phase to tricalcium phosphate, inhibiting densification in the HA/glass composites. However, depending on the glass concentration, some of the glass can act as a sintering aid enhancing the densification in the composites. © 2013 IEEE.

Relating Ph And Ion Release From Ga2o3-Na 2o-Cao-Zno-Sio2 Bioactive Glasses, T. J. Keenan, A. W. Wren, A. Coughlan, Mark R. Towler, M. M. Hall

Chemical and Biochemical Engineering Faculty Research & Creative Works

Three glasses were designed for this study, including one Ga-free glass (Control), and two Ga-containing glasses (TGa-1, TGa-2). In the Ga-containing glasses, Ga₂O₃ is included at the expense of ZnO. This study focuses on the relation between pH and ion concentration present in solution in which these bioactive glasses have been submerged for periods of 1, 7, and 14 days. © 2013 IEEE.

Physiological Fluid Specific Agglomeration Patterns Diminish Gold Nanorod Photothermal Characteristics, Kristen K. Comfort, Jared W. Speltz, Bradley M. Stacy, Larry R. Dosser, Saber M. Hussain

Chemical and Materials Engineering Faculty Publications

Investigations into the use of gold nanorods (Au-NRs) for biological applications are growing exponentially due to their distinctive physicochemical properties, which make them advantageous over other nanomaterials. Au-NRs are particularly renowned for their plasmonic characteristics, which generate a robust photothermal response when stimulated with light at a wavelength matching their surface plasmon resonance. Numerous reports have explored this nanophotonic phenomenon for temperature driven therapies; however, to date there is a significant knowledge gap pertaining to the kinetic heating profile of Au-NRs within a controlled physiological setting. In the present study, the impact of environmental composition on Au-NR behavior and degree …

Synthesis Of Pani/Nihcf Nanocomposite Particles And Eqcm Measurement Of Ion Exchange Properties In Solutions Containing Cd2+, Yu-Jiao Yang, Xiao-Gang Hao, Xu-Li Ma, Zhong-De Wang, Zhong-Lin Zhang, Nian-Chen Han

Journal of Electrochemistry

The PANI/NiHCF nanocomposite particles were synthesized on the CNTs-modified Pt substrate by one-step co-polymerization using cyclic voltammetry. Electrochemical quartz crystal microbalance (EQCM) technique was adopted to investigate the polymerization process of the nanocomposite particles and the mechanism of ion exchange in aqueous solution containing Cd²⁺． The morphology and structure of the as-prepared composite particles were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FT-IR). Combined with cyclic voltammetry (CV) and energy dispersive spectroscopy (EDS), the electrochemical behavior and the mechanism of ion exchange were also investigated in electrolytes of Cd^{2+ …}

A Comparative Study In Pretreatments Of Acid Chemical Wastewater By Electrochemical Oxidation And Ozonation, Han-Shui Liu, Su Yu, Shao-Ping Tong, Chun-An Ma

Journal of Electrochemistry

Under the condition of keeping certain acidity, the pretreatment efficiency of an acid chemical wastewater (pH 0.85) by electrochemical oxidation was compared with that by ozonation. The results showed that the electrochemical oxidation pretreatment could obtain a better result than the ozonation at pH 0.85. After the addition of 2 g·L^-1 NaCl and with the electrochemical oxidation pretreatment at 30 mA·cm^-2, the removal rate of chemical oxygen demand (CODCr) reached 43.4%, and the value of biochemical oxygen demand/chemical oxygen demand (BOD₅/COD_Cr) also increased from 0.034 to 0.14 in 20 minutes, indicating significantly improvement …

Preparation Of Benzoquinone From Phenol By Electrooxidation, Dong-Fang Niu, Cheng-Kai Yu, Xin-Sheng Zhang

Journal of Electrochemistry

The benzoquinone was prepared from phenol by electrooxidation in an H-type cell with cation exchange membrane, in which lead plates were used both as an anode and a cathode, while H₂SO₄ was used as a supporting electrolyte. The effects of current density, concentration of sulphuric acid, concentrations of benzoquinone in electrolyte and extractant on the yields and efficiencies of electrolysis were investigated. Under the optimized conditions of current density being 4 A·dm^-2, concentration of sulphuric acid 1 mol·L^-1, passed charge 3.2 A·h, the yield and current efficiency of benzoquinone could reach 68% and …

Experimental Design Methodology Applied To The Oxidation Of Quinolines In Aqueous Medium By Electro-Fenton Process, Souhaila Trabelsi Souissi, Nihal Oturan, Nizar Bellakhal, Mehmet A. Oturan

Journal of Electrochemistry

The degradation behavior of 8-hydroxyquinoleine sulfate (8-HQS), a model molecule of quinolines, was studied in an aqueous medium by electro-Fenton process using a carbon felt cathode and a platinum anode. The great oxidation ability of this process is due to a large production of hydroxyl radical (OH) by electrochemically induced Fenton’s reagent (H₂O₂, Fe²⁺). Hydroxyl radicals are very powerful oxidizing agents which react on organics up to complete mineralization. A factorial experimental design was used for determining the operating parameters on the degradation of 8-HQS in an aqueous medium. The results showed that the …

Engineered Nanotopography On Electrospun Plla Microfibers Modifies Raw 264.7 Cell Response, Nicholas J. Schaub, Tara Britton, Rupak Rajachar, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this study, we created a new method of electrospinning capable of controlling the surface structure of individual fibers (fiber nano topography). The nano topographical features were created by a phase separation in the fibers as they formed. To control the phase separation, a nonsolvent (a chemical insoluble with the polymer) was added to an electrospinning solution containing poly-l-lactic acid (PLLA) and chloroform. The nano topography of electro spun fibers in the PLLA/chloroform solution was smooth. However, adding a small weight (< 2% of total solution) of a single nonsolvent (water, ethanol, or dimethyl sulfoxide) generated nanoscale depressions on the surface of the fibers unique to the nonsolvent added. Additionally, nanoscale depressions on electro spun fibers were observed to change with dimethyl sulfoxide (DMSO) concentration in the PLLA/chloroform solution. A nonlinear relationship was found between the concentration of DMSO and the number and size of nano topographical features. The surface depressions did not alter the hydrophobicity of the scaffold or degradation of the scaffold over a two-day period. To determine if fiber nano topography altered cell behavior, macrophages (RAW 264.7 cells) were cultured on fibers with a smooth nano topography or fibers with nanoscale depressions. RAW 264.7 cells spread less on fibers with nanoscale depressions than fibers with a smooth topography (p < 0.05), but there were no differences between groups with regard to cell metabolism or the number of adherent cells. The results of this study demonstrate the necessity to consider the nano topography of individual fibers as these features may affect cellular behavior. More importantly, we demonstrate a versatile method of controlling electro spun fiber nano topography. © 2013 American Chemical Society.

Modeling The Relaxation Time Of Dna Confined In A Nanochannel, Douglas R. Tree, Yanwei Wang, Kevin D. Dorfman

Faculty Publications

Using a mapping between a Rouse dumbbell model and fine-grained Monte Carlo simulations, we have computed the relaxation time of λ-DNA in a high ionic strength buffer confined in a nanochannel. The relaxation time thus obtained agrees quantitatively with experimental data [Reisner et al., Phys. Rev. Lett. 94, 196101 (2005)] using only a single O(1) fitting parameter to account for the uncertainty in model parameters. In addition to validating our mapping, this agreement supports our previous estimates of the friction coefficient of DNA confined in a nanochannel [Tree et al., Phys. Rev. Lett. 108, 228105 …

The Use Of Near Infrared And Microwave Sensing For On-Line Real Time Monitoring Of Moisture Content And Composition Of Powder Blend, Ryan V. Mcdonnell, Anshu Gupta, John Austin, Michael T. Harris, Gintaras V. Reklaitis

The Summer Undergraduate Research Fellowship (SURF) Symposium

Online process analytics has been a topic of interest by pharmaceutical companies as a method of determining how operating parameters affect the final quality of their products. One form of online process analytics that has been found to be effective is microwave sensing. While it has been found that microwave resonance sensing can be used to measure parameters such as moisture content and density, it has yet to be discovered if such sensors have the ability to measure changes in content uniformity of raw materials pharmaceutical companies use. Data was collected using a spin riffler fitted with a microwave sensor …

Optimization Of Polymer Separation By Gradient Polymer Elution Chromatography, Gideon R. Liem, Linda Nien-Hwa Wang

The Summer Undergraduate Research Fellowship (SURF) Symposium

High Performance Liquid Chromatography (HPLC) has been a versatile separation method for polymers for many years. Analysis of different polymers by HPLC is typically done by utilizing the differential solubility of the polymers by mixing a good solvent and an anti-solvent in various compositions. This method is called Gradient Polymer Elution Chromatography (GPEC). While GPEC has been used extensively, it commonly uses a linear gradient to separate components. Linear solvent gradients consume a lot of solvent and take a relatively long time (> 30 minutes) to complete. The goal of this study is to develop a step gradient from a …

Advanced Visualization Techniques Of Hot-Jet Combustion Of Lean And Ultra-Lean Substances, Timothy I. Machin, Li Qiao

The Summer Undergraduate Research Fellowship (SURF) Symposium

Research has been conducted on ignition of natural gas as a potential replacement for fossil fuels. A reason natural gas is not widely used and adapted is because of the harmful emissions created when combusted in rich mixtures, but if the gas can be burned at a lean or ultra-lean equivalence ratio, these emissions can be reduced or even eliminated. One method of burning lean and ultra-lean substances is by use of hot-jet ignition. This method ignites the substance near its combustion temperature, reducing the harmful emissions. This method is not yet fully understood, and so research must be done …

Dna Based Carbon Nanotube Porphyrin Nanohybrids Molecular Recognization And Regeneration, Molly M. Riccitelli, Hanyu Zhang, Jong Hyun Choi

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the search to improve solar cells, scientists are exploring new materials that will provide better current transfer. One material that has emerged as a strong contender is the single walled carbon nanotube (SWNT). Current DNA-SWNT based films combined with chromophores have poor operational lifetimes compared to commercial solar cells. Once exposed to light the chromophore begins to degrade, eventually rendering the solar cell unusable. To solve this problem, we used a method involving multiple steps. First we found which DNA sequences formed structures around the SWNT that could hold the most chromophores by using a spectrophotometer to test the …

A Generalized Design For Affinity Chromatography Columns, Lee-Wei Kao, Nien-Hwa Linda Wang

The Summer Undergraduate Research Fellowship (SURF) Symposium

In affinity chromatography, an adsorbent with a high selectivity for a target solute is used to isolate the target molecule from other impurities. With sufficient selectivity, the target molecule can be isolated in a highly purified and concentrated state. Common applications of affinity chromatography include Protein A chromatography for antibody purification and Immobilized Metal Affinity Chromatography (IMAC) for protein purification. The well-known design method based on constant-pattern mass transfer zone analysis does not apply to small feed batches, which are insufficient to form constant-pattern frontal waves. Other literature design methods rely on simulation or experimental trials that can be time-consuming …

Non-Mass Transfer Limited Crystal Growth, Ryan J. Smyth, Caitlin Schram, Stephen P. Beaudoin

The Summer Undergraduate Research Fellowship (SURF) Symposium

There are many different active pharmaceutical ingredients (APIs) that have been discovered in research labs all around the world that can be used to treat and cure patients with a variety of different ailments. The challenge with these APIs in treatments is that they are not soluble in water, thus they low absorption into the blood stream (bio-availability). The key to making these APIs more bio-available is to understand how they grow as crystals and drop out of the aqueous solutions. One of the ways these APIs were made more bio-available is to render them amorphous and suspend them in …

Synthesis And Characterization Of Bismuth Telluride Nanoparticles For Use In Flexible Polymer-Nanoparticle Hybrid Thermoelectric Devices, Alexander R. Muller, Bryan Boudouris, Edward P. Tomlinson

The Summer Undergraduate Research Fellowship (SURF) Symposium

Polymer-based thermoelectric materials, which can have readily-tuned properties through simple control of their chemistry, offer the promise of providing flexible, lightweight, and low-cost modules for the environmentally-friendly conversion of waste heat to electricity without the need for moving parts. As such, they have started to be explored in applications ranging from improved building efficiency to increased mileage in automobiles. However, widespread implementation of these materials is limited due to their low performance relative to their mechanically-rigid, heavy inorganic material-based counterparts. Therefore, a critical need exists to design polymer-nanoparticle composite materials to increase the energy conversion of thin film thermoelectric devices. …

Multi-Factorial Stability Study Of Metabolites, Ruijun Zheng, John A. Morgan

The Summer Undergraduate Research Fellowship (SURF) Symposium

Previous research done on metabolites has found that high energy compounds like adenosine triphosphate(ATP), nicotinamide adenine dinucleotide phosphate reduced (NADPH) or nicotinamide adenine dinucleotide reduced (NADH) are unstable in cell extracts at relatively high temperature and acidic condition. The multifactorial stability study of metabolites enables us to verify the best condition of storage for these energy compounds and sugar phosphates, as well as to strengthen the understanding of metabolism in biological study. As the most solvents for high performance liquid chromatography (HPLC) are acidic and unfavorable for these energy compounds, it is necessary to perform a detailed study about …

Tobacco Mosaic Virus Implemented As An Interfacial Layer In Organic Photovoltaic Cells, Monica D. Del Real, Bryan Boudouris

The Summer Undergraduate Research Fellowship (SURF) Symposium

Organic photovoltaics (OPVs) are flexible, light weight, and economical to produce due to low processing temperatures, solution processing, and print fabrication. This makes them optimal for a wide range of applications. However, the efficiencies of OPVs are currently not high enough for them to be viable in the market or to be able to compete with inorganic photovoltaics. Therefore the integration of new materials and methods into OPVs in order to increase their efficiency is a vital field. One way to increase the efficiency of OPVs is to increase the surface area in-between layers to allow for enhanced electron transport. …

Experimental Study Of Co2 Recycling Using Metal-Oxide Enhanced Coconut Char Gasification: Catalytic Effect Of Potassium Carbonate On Gasification, Mengqi Gao, Indraneel Sircar, Jay P. Gore

The Summer Undergraduate Research Fellowship (SURF) Symposium

Biomass gasification is an important process in the production of bio-derived fuels and renewable energy. Biomass gasification with CO₂ is an endothermic process requiring high temperatures, resulting in low process-efficiency. Metals found in the ash in biomass feedstock have shown rate-promoting effects on the C-CO₂ reaction and have motivated the study of low-temperature catalytic gasification. The present study investigates the catalytic effects of potassium (K) on the biomass gasification reactivity of a coconut-derived char (>99.9% carbon) within the temperature range of 600 – 1000 ^oC. A wet-impregnation technique is used to prepare K-treated chars. Gasification of …

Database For Solar Energy Group, Lei Zhong, Rakesh Agrawal

The Summer Undergraduate Research Fellowship (SURF) Symposium

Copper zinc tin sulfide (CZTS) is the abundant quaternary semiconducting compound which could be used to make solar thin film. Even though its efficiency is lower than the silicon based film, the cost of CZTS solar film will be lower compared to the current silicon based film. Therefore it is really worth to do research and make improvement on its efficiency. So far, the solar energy group already collected a great bunch of data, which could be employed to guide the future experiment. Hence, it is really necessary to build a database to arrange the information we got. Our project …