Chemical Engineering Commons^™

Photocrosslinked Methylcellulose Hydrogels For Controlled Protein Release, Das Dritiman

Dissertations and Theses

No abstract provided.

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.

Synthesis Of 4-Azidocoumarins And Their Use In Copper-Catalyzed Azide-Alkyne Cycloaddition Reactions, Anthony J. Netsuri

Dissertations and Theses

Triazole-containing compounds have shown great biological activity ranging from antiviral, antibacterial, to anticancer, to name a few. Coumarin derivatives have also shown interesting biological activities. The combination of these bioactive compounds appears to have great promise for new and future medicines. In this work, various 4-azido-coumarins were synthesized via the transformation of the 4-hydroxy derivatives to 4-benzotriazolyloxy coumarins by reaction with the peptide coupling agent (benzotriazol-1-yloxy)tris-(dimethylamino)phosphonium hexafluorophosphate (BOP), and 1,8-diazabicycloundec-7-ene (DBU) as the base, in tetrahydrofuran (THF) solvent. The 4-benzotriazolyloxy coumarins were converted to the 4-azidocoumarins by reaction with sodium azide (NaN3), and the overall process was simplified to a …

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, Biomolecular, and Materials 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 …

Induction Of Microalgal Lipids For Biodiesel Production In Tandem With Sequestration Of High Carbon Dioxide Concentration, Wilbel J. Brewer

Dissertations, Master's Theses and Master's Reports - Open

There is no doubt that sufficient energy supply is indispensable for the fulfillment of our fossil fuel crises in a stainable fashion. There have been many attempts in deriving biodiesel fuel from different bioenergy crops including corn, canola, soybean, palm, sugar cane and vegetable oil. However, there are some significant challenges, including depleting feedstock supplies, land use change impacts and food use competition, which lead to high prices and inability to completely displace fossil fuel ^[1-2]. In recent years, use of microalgae as an alternative biodiesel feedstock has gained renewed interest as these fuels are becoming increasingly economically viable, …

Selective Mercury Sequestration From A Silver/Mercury Cyanide Solution, Kristen L. Gabby

Dissertations, Master's Theses and Master's Reports - Open

Silver and mercury are both dissolved in cyanide leaching and the mercury co-precipitates with silver during metal recovery. Mercury must then be removed from the silver/mercury amalgam by vaporizing the mercury in a retort, leading to environmental and health hazards. The need for retorting silver can be greatly reduced if mercury is selectively removed from leaching solutions.

Theoretical calculations were carried out based on the thermodynamics of the Ag/Hg/CN- system in order to determine possible approaches to either preventing mercury dissolution, or selectively precipitating it without silver loss. Preliminary experiments were then carried out based on these calculations to determine …

Electrospun Quaternized Chitosan Fibers For Virus Removal From Drinking Water, Xue Mi

Dissertations, Master's Theses and Master's Reports - Open

Membrane filtration has become an accepted technology for the removal of pathogens from drinking water. Viruses, known to contaminate water supplies, are too small to be removed by a size-exclusion mechanism without a large energy penalty. Thus, functionalized electrospun membranes that can adsorb viruses have drawn our interest. We chose a quaternized chitosan derivative (HTCC) which carries a positively-charged quaternary amine, known to bind negatively-charged virus particles, as a functionalized membrane material. The technique of electrospinning was utilized to produce nanofiber mats with large pore diameters to increase water flux and decrease membrane fouling. In this study, stable, functionalized, electrospun …

Sustainable Energy Production In The United States: Life Cycle Assessment Of Biofuels And Bioenergy, Jiqing Fan

Dissertations, Master's Theses and Master's Reports - Open

The United States of America is making great efforts to transform the renewable and abundant biomass resources into cost-competitive, high-performance biofuels, bioproducts, and biopower. This is the key to increase domestic production of transportation fuels and renewable energy, and reduce greenhouse gas and other pollutant emissions.

This dissertation focuses specifically on assessing the life cycle environmental impacts of biofuels and bioenergy produced from renewable feedstocks, such as lignocellulosic biomass, renewable oils and fats. The first part of the dissertation presents the life cycle greenhouse gas (GHG) emissions and energy demands of renewable diesel (RD) and hydroprocessed jet fuels (HRJ). The …

Production Of Recombinant Trichoderma Reesei Endoglucanase Protein Cel7b By Using Kluyveromyces Lactis, Zainab Ibrahim Alshoug

Dissertations, Master's Theses and Master's Reports - Open

This research is about producing recombinant Trichoderma reesei endoglucanase Cel7B by using Kluyveromyces lactis, transformed with chromosomally integrated Cel7B cDNA, as a host cell (K. lactis Cel7B). Cel7B is one of the glycoside hydrolyze family of proteins that are produced by T. reesei. Cel7B together with other endoglucanases, exoglucanases, and â-glucosidases hydrolyze cellulose to glucose, which can then be fermented to biofuels or other value-added products.

The research objective of this MS project is to examine favorable fermentation conditions for recombinant Cel7B enzyme production and improved activity. Production of enzyme on different types of media was examined, and the activity …

A Novel Approach To Carbon Dioxide Capture And Storage, Brett P. Spigarelli

Dissertations, Master's Theses and Master's Reports - Open

The novel approach to carbon capture and storage (CCS) described in this dissertation is a significant departure from the conventional approach to CCS. The novel approach uses a sodium carbonate solution to first capture CO₂ from post combustion flue gas streams. The captured CO₂ is then reacted with an alkaline industrial waste material, at ambient conditions, to regenerate the carbonate solution and permanently store the CO₂ in the form of an added value carbonate mineral. Conventional CCS makes use of a hazardous amine solution for CO₂ capture, a costly thermal regeneration stage, and the underground storage …

Computational Prediction Of The Sporulation Network In Clostridium Thermocellum, Changyi Jiang

Dissertations, Master's Theses and Master's Reports - Open

Sporulation is a process in which some bacteria divide asymmetrically to form tough protective endospores, which help them to survive in a hazardous environment for a quite long time. The factors which can trigger this process are diverse. Heat, radiation, chemicals and lacking of nutrition can all lead to the formation of endospores. This phenomenon will lead to low productivity during industrial production. However, the sporulation mechanism in a spore-forming bacterium, Clostridium theromcellum, is still unclear. Therefore, if a regulation network of sporulation can be built, we may figure out ways to inhibit this process. In this study, a …

Applications Of Antioxidant And Anti-Inflammatory Polymers To Inhibit Injury And Disease, David B. Cochran

Theses and Dissertations--Chemical and Materials Engineering

There is an undeniable link between oxidative stress, inflammation, and disease. Currently, approaches using antioxidant therapies have been largely unsuccessful due to poor delivery and bioavailability. Responding to these limitations, we have developed classes of polymer and delivery systems that can overcome the challenges of antioxidant and anti-inflammatory therapy. In our initial studies, nanoparticles of poly(trolox), a polymeric form of trolox, were surface-modified with antibodies. This modification allows for specific targeting to endothelial cells, affording controllable and localized protection against oxidative stress. We have shown these targeted nanoparticles bind, internalize, and provide protection against oxidative stress generation and cytotoxicity from …

The Effects Of Ceria Addition On Aging And Sulfation Of Lean Nox Traps For Stand Alone And Lnt-Scr Applications, Vencon G. Easterling

Theses and Dissertations--Chemical and Materials Engineering

THE EFFECTS OF CERIA ADDITION ON AGING AND SULFATION OF LEAN NO_x TRAPS FOR STAND ALONE AND LNT-SCR APPLICATIONS

Model powder and fully formulated monolithic lean NO_x trap (LNT) catalysts were used to investigate the effect of ceria on desulfation behavior. Temperature-programmed reduction (TPR) experiments (model catalysts) showed each of the oxide phases present is able to store sulfur and possesses distinct behavior (temperature at which desulfation occurs). La-CeO₂ or CeO₂-ZrO₂-containing samples (monoliths) showed a greater resistance to deactivation during sulfation and required lower temperatures to restore the NO_x storage efficiency to …

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 …

Chme 223: Chemical Engineering Thermodynamics I—A Peer Review Of Teaching Project Benchmark Portfolio, Hossein Noureddini

UNL Faculty Course Portfolios

This portfolio was intended to provide a broad overview of the course. Initially, when I decided to write this portfolio my intention was for it to help me in the student's outcome assessment of teaching for the course and in a broader scope, for my department's effort in establishing a systematic student outcome assessment process. However, as I became more familiar with the program I realized other aspects of the course could also benefit from this portfolio. My goal for this portfolio is to be broad with emphasis on course objectives, delivery methods and their assessment. I like for this …

Asymmetric Hydrogenation Of Α, Β-Unsaturated Carboxylic Acid Over Chiral-Modified Palladium Catalyst, Shuai Tan

Theses and Dissertations

The production of optically pure chemicals through enantioselective catalytic reaction plays a key role a variety of industrials (e.g., pharmaceutical, agrochemical). Among several established methods, chiral-modified supported transition metal catalyst has been addressed attentions since past decades due to an environmental concern. Asymmetric hydrogenation of α, β-unsaturated carboxylic acid over Pd catalyst is of particular interest in this area. Nevertheless, the spectroscopic aspect, as well as the kinetic mechanism of such reaction system are still not clearly understood and require further study. In this work, a model catalytic reaction has been investigated from both spectroscopic and kinetic view. To be …

Preparation Of Cobalt/Nickel Molybdenum Sulfide Catalysts Supported By Aqueous Media Soluble Multi-Wall Carbon Nanotubes., Hassan Ahmad Bleibel

Open Access Theses & Dissertations

Multi-walled carbon nanotubes (MWCNTs) have been subjected to chemical treatment in order to introduce hydrophilic functional groups on their surfaces. These covalently bonded groups did enhance the solubility of MWCNTs in aqueous media as expected. Functionalized MWCNTs were characterized using FTIR, Raman spectroscopy, TGA, X-ray diffraction, dispersion test and TEM. Then, functionalized MWCNTs were incorporated in the hydrothermal synthesis method of transition metal sulfide catalysts (CoMo, NiMo, and Ethylenediamine-CoMo Sulfides). Catalysts were characterized using X-ray diffraction, TEM, SEM, N2 Gas adsorption-desorption, elemental analysis, and Hydrodesulfurization (HDS) reaction of dibenzothiophene (DBT). The objective was to study the functionalized MWCNTs' effect; being …

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 …

Theoretical Investigation Of The Water-Gas Shift Reaction At The Three Phase Boundary Of Ceria Supported Platinum Metal Clusters, Sara Aranifard

Theses and Dissertations

The Water-Gas Shift (WGS: CO+H2O→CO2+H2) reaction is a key step in hydrogen fuel processing for mobile fuel cell applications. Since the reaction is equilibrium-limited and exothermic, high conversions are favored by low temperatures. However, conventional low-temperature shift catalysts are not active enough. Reducible oxide supported small noble metal clusters have shown excellent activity as low temperature WGS catalysts and it is generally believed that these catalysts are bifunctional. In other words, the reaction occurs at the three-phase boundary (TPB) of the noble metal, the reducible oxide, and the gas phase. The small noble metal cluster adsorbs/activates the CO molecules and …

Understanding The Effect Of Balance Of Plant Contaminants On Pemfcs Performance: Models, Mechanisms, Functional Group, Hyun-Seok Cho

Theses and Dissertations

This dissertation considers contamination of a proton exchange membrane fuel cell (PEMC) that may result from chemicals that leach from balance of plant (BOP) materials. Both model predictions and experimental data are presented. The model is used to predict the cathode contamination impact on the Pt/C electrode and the membrane assuming no transport of contaminant from cathode to anode. The model prediction accounts for the contamination mechanisms such as adsorption, ion-exchange, absorption and three sources of voltage (i.e., performance) loss. The simple 2-D time-dependent model is developed by considering well known chemical engineering concepts of Langmuir adsorption, partition coefficients, plug …