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Development Of Stable Silica Washcoats For Monolithic Substrates, Ethan A. Mastny, Dr. Calvin H. Bartholomew 2014 Brigham Young University

Development Of Stable Silica Washcoats For Monolithic Substrates, Ethan A. Mastny, Dr. Calvin H. Bartholomew

Journal of Undergraduate Research

The objective was to develop an efficient procedure for depositing silica washcoats onto cellular, ceramic monoliths while ensuring that the silica maintains its desired properties of surface area and pore structure and is stable against erosion. Catalyst coated ceramic monoliths find application in automotive emissions control and other areas of pollution abatement.


The Effect Of Material Choice On Thromboembolism, Peter M. Crapo, Dr. Kenneth Solen 2014 Brigham Young University

The Effect Of Material Choice On Thromboembolism, Peter M. Crapo, Dr. Kenneth Solen

Journal of Undergraduate Research

Stroke, heart attack, or other severe medical problems may arise when platelet aggregates block a patient’s blood vessels. These aggregates form when blood is exposed to foreign surfaces in biomedical equipment. When blood is first exposed to a foreign surface, platelets adhere to the surface. A cluster of platelets on the surface is called a thrombus. Thrombi grow as more platelets adhere, and the momentum of passing fluid or other causes may dislodge them. Dislodged thrombi are called emboli, and the entire process is called thromboembolism. Thromboembolism cannot be entirely avoided in blood-contacting devices, such as artificial organs.


Ultrasound-Activated Delivery Of Doxorubicin From Polymeric Micelles To Breast Cancer Cells, Philip D. Blood, Dr. William G. Pitt 2014 Brigham Young University

Ultrasound-Activated Delivery Of Doxorubicin From Polymeric Micelles To Breast Cancer Cells, Philip D. Blood, Dr. William G. Pitt

Journal of Undergraduate Research

A major limitation to the effectiveness of cancer chemotherapy is the toxic side effects it has on normal tissues. Thus, it would be highly advantageous to develop a form of treatment that allows higher doses of drugs to be delivered to tumors without increasing the amount of drug absorbed by healthy tissues. To this end, various controlled drug delivery systems are being devised which aim to preferentially target cancerous tissue.


Low-Frequency Ultrasound Increases Outer Membrane Permeability Of Pseudomonas Aeruginosa And Escherichia Coli, Christopher M. Runyan, Dr. William G. Pitt 2014 Brigham Young University

Low-Frequency Ultrasound Increases Outer Membrane Permeability Of Pseudomonas Aeruginosa And Escherichia Coli, Christopher M. Runyan, Dr. William G. Pitt

Journal of Undergraduate Research

Our lab has investigated the use of low-frequency ultrasound as an adjuvant to antibacterial therapy. We have found that ultrasound can increase killing of certain combinations of antibiotics with bacteria. Ultrasound at very low frequencies, alone, may kill bacteria; however, these frequencies are harmful to other living tissues and can not be used in a clinical setting. While ultrasound does not kill bacteria at slightly higher frequencies, it can enhance antibiotic killing, a phenomenon known as the “bioacoustic effect.”


Waste Not, Want Not, Mary Cragun, Dr. William Hecker 2014 Brigham Young University

Waste Not, Want Not, Mary Cragun, Dr. William Hecker

Journal of Undergraduate Research

The treatment of wastewater or sewage is a multi-step process. One of the steps involves the treatment of the organic mass collected during the treatment process. There are several different methods of treating this organic mass or sludge. At the Springville Wastewater Treatment Facility, the sludge is decomposed under anaerobic conditions into simpler forms of organic solids for safe disposal. Two different types of bacteria are used to decompose the sludge. The products of the sludge decomposition are methane, carbon dioxide, water, and simpler organic solids. The amount of methane produced by the bacteria depends on the system used and …


A Stable Coating For Silica Supported Fisher-Tropsch Catalysts, Nathan M. Cluff, Dr. Calvin Batholomew 2014 Brigham Young University

A Stable Coating For Silica Supported Fisher-Tropsch Catalysts, Nathan M. Cluff, Dr. Calvin Batholomew

Journal of Undergraduate Research

Our daily lives are dependent upon petroleum. This is evident in the fact that 26.4% of the United States’ energy consumption is used directly for transportation in the form of liquid fuels.1 To prevent shortages in gasoline, jet fuel, home heating oil, and other petroleum products, alternatives will be needed to supplement the rising world demand. As a citizen that will raise a family during a time when alternative energy sources will need to be implemented, I have a keen interest in how we will meet our energy needs and where we will get those resources. One alternative is the …


Synthesis Of Carbon Nitrides From Carbon Dioxide, Yun Hang Hu 2014 Michigan Technological University

Synthesis Of Carbon Nitrides From Carbon Dioxide, Yun Hang Hu

Michigan Tech Patents

Provided are methods of converting carbon dioxide to carbon nitrides. In a first reaction, carbon dioxide may be reacted with metal nitrides, such as Li.sub.3N, to form carbon nitrides in a fast and exothermic reaction. Also provided are methods of using product metal cyanamides from the first reaction to subsequently generate additional carbon nitrides.


Deactivation Of V2o5-Based Catalysts Used In The Selective Catalytic Reduction Of Nox, Aaron Nackos, Dr. Calvin H. Bartholomew 2014 Brigham Young University

Deactivation Of V2o5-Based Catalysts Used In The Selective Catalytic Reduction Of Nox, Aaron Nackos, Dr. Calvin H. Bartholomew

Journal of Undergraduate Research

Nitric oxides (NO and NO2, or NOx for short) are significant contributors to photochemical smog and acid rain and are mainly produced from automobile emissions and from coal combustion used to generate electric power. Because of these issues, the EPA will require by the year 2004 that NOx emissions from coal-fired plants in this country meet strict pollution limitations—up to a 90% reduction in the amount of NOx currently allowed to be released by the EPA (Belden 41).


Laboratory Design And Construction For Catalyst Characterization, Kenneth G. Crowther, Dr. Larry Baxter 2014 Brigham Young University

Laboratory Design And Construction For Catalyst Characterization, Kenneth G. Crowther, Dr. Larry Baxter

Journal of Undergraduate Research

In the midst of industrial development we sometimes fail to foresee problems that may arise from current, seemingly economical, methods of production. One oversight in many industries ranging from Power to Caprolactam production is nitrogen oxide (NOX) emissions that damage our bodies and limit visibility. NOX are highly reactive molecules that are responsible for the formation of ground level ozone, acid aerosols, acid rain, and photochemical smog; all which pose a threat to the health of humans and other living things. This problem, however, is finally noticed. Government legislation is going into effect that is reducing the amounts of NOX …


Environmental Stress Cracking Of Glassy Polymers, Parthasakha Neogi, Gholamreza Zahedi 2014 Missouri University of Science and Technology

Environmental Stress Cracking Of Glassy Polymers, Parthasakha Neogi, Gholamreza Zahedi

Chemical and Biochemical Engineering Faculty Research & Creative Works

When a glassy polymer is exposed to an organic solvent, it can crack spontaneously or fail more readily under extension. This is environmental stress cracking. When the solvent diffuses into the polymer, stresses develop because of swelling of the polymer. In addition, fluctuations give rise to stresses, because of the variation in surface tension from changes in the surface concentration of the solute, which is the Marangoni effect. A linear stability analysis is performed to show that such a system is unstable to infinitesimal disturbances. Large tensile stresses arise locally, leading to failures, which will be observed in the interfacial …


A New Software Tool To Environmentally And Economically Evaluate Solvent Recovery In The Pharmaceutical Industry, Eduardo Cavanagh 2014 Rowan University

A New Software Tool To Environmentally And Economically Evaluate Solvent Recovery In The Pharmaceutical Industry, Eduardo Cavanagh

Theses and Dissertations

The environmental impact reduction and operating costs savings associated with the purification and reuse of solvent waste in the manufacture of active pharmaceutical ingredients (API's) were investigated. A software toolbox has been developed that combines Aspen Plus(R) process simulation with SimaPro(R) and Ecosolvent life cycle assessment (LCA) databases. The feasibility of a relatively small flexible skid capable of recovering multiple solvent waste streams was evaluated. Fractional distillation and pervaporation were considered to separate binary solvent waste mixtures. Optimum distillation reflux ratio and feed stage were determined to maximize the environmental impact reductions and operating cost savings. The optimum reflux ratio …


Process For The Purification Of Benzphetamine Hydrochloride, Keith Tomazi 2014 Missouri University of Science and Technology

Process For The Purification Of Benzphetamine Hydrochloride, Keith Tomazi

Chemical and Biochemical Engineering Faculty Research & Creative Works

The present invention relates to the economical and separation of benzphetamine hydrochloride and methamphetamine by liquid extraction. An extraction process employing a suitable organic solvent and water at a pH in the range of from about 6 to about 8 provides excellent removal of the methamphetamine by dissolution in the water phase while the benzphetamine dissolves in the organic phase. Simple separation of the two phases results in separation of the two amines.


Orientation-Dependent Pseudomorphic Growth Of Inas For Use In Lattice-Mismatched Mid-Infrared Photonic Structures, Gregory Edward Triplett, Charles Meyer, Emily Cheng 2014 Virginia Commonwealth University

Orientation-Dependent Pseudomorphic Growth Of Inas For Use In Lattice-Mismatched Mid-Infrared Photonic Structures, Gregory Edward Triplett, Charles Meyer, Emily Cheng

Electrical and Computer Engineering Publications

In this study, InAs was deposited on GaAs (100) and GaAs (111)B 2 degrees towardssubstrates for the purpose of differentiating the InAs growth mode stemming from strain and then analyzed using in-situ reflection high energy electron diffraction, scanning electron microscopy, Raman spectroscopy, reflectance spectroscopy, and atomic force microscopy. The procession of InAs deposition throughout a range of deposition conditions results in assorted forms of strain relief revealing that, despite lattice mismatch for InAs on GaAs (approximately 7%), InAs does not necessarily result in typical quantum dot/wire formation on (111) surfaces, but instead proceeds two-dimensionally due primarily to the surface orientation.


Combining Monte Carlo Transport And Level Set Surface Evolution For Modeling Vapor Phase Deposition Of Thin Films Over Sub-Micron Features, John Lewis Smith 2014 Rose-Hulman Institute of Technology

Combining Monte Carlo Transport And Level Set Surface Evolution For Modeling Vapor Phase Deposition Of Thin Films Over Sub-Micron Features, John Lewis Smith

Graduate Theses - Chemical Engineering

A hybrid scheme is used to model the vapor phase deposition of thin films at the feature scale. The transport of the chemical species to the substrate surface is modeled with a Collisionless Direct Simulation Monte Carlo (DSMC) method. The Level Set Method is used to model the growth of the thin-film on the substrate. The convergence criteria for these methods were not found in literature.

The governing equations for the Level Set Method are, in general, non-linear partial differential equations. The coupling of the DSMC Method with the Level Set Method results in a set of non-Gaussian stochastic non-linear …


Aging Of A Polymer Core Composite Conductor Under Combined Ozone And Temperature Conditions, James M. Middleton 2014 University of Denver

Aging Of A Polymer Core Composite Conductor Under Combined Ozone And Temperature Conditions, James M. Middleton

Electronic Theses and Dissertations

The next generation High Temperature Low Sag Polymer Core Composite Conductors (HTLS PCCC) can experience harsh in-service environments including high temperature and highly concentrated ozone. In some extreme cases, it is possible that the conductors will experience temperatures of up to 180°C and ozone concentrations as high as 1% (10,000 ppm). Therefore, the primary goal of this research was to determine the most damaging aging conditions which could negatively affect the in-service life of the conductors. This included characterizing the aging in ozone and at high temperature of the HTLS PCCC hybrid composite rods and neat resin. It was found …


Economic Profitability Of The Bakken, North Dakota Unconventional Oil Plays Based On A Typical Well Performance With Current Market Conditions, Mehmet Apaydin 2014 Michigan Technological University

Economic Profitability Of The Bakken, North Dakota Unconventional Oil Plays Based On A Typical Well Performance With Current Market Conditions, Mehmet Apaydin

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

Increases in oil prices after the economic recession have been surprising for domestic oil production in the United States since the beginning of 2009. Not only did the conventional oil extraction increase, but unconventional oil production and exploration also improved greatly with the favorable economic conditions. This favorable economy encourages companies to invest in new reservoirs and technological developments. Recently, enhanced drilling techniques including hydraulic fracturing and horizontal drilling have been supporting the domestic economy by way of unconventional shale and tight oil from various U.S. locations. One of the main contributors to this oil boom is the unconventional oil …


Analysis Of A Chemical Model System Leading To Chiral Symmetry Breaking: Implications For The Evolution Of Homochirality, Brandy N. Morneau, Jaclyn M. Kubala, Carl Barratt, Pauline Schwartz 2014 University of New Haven

Analysis Of A Chemical Model System Leading To Chiral Symmetry Breaking: Implications For The Evolution Of Homochirality, Brandy N. Morneau, Jaclyn M. Kubala, Carl Barratt, Pauline Schwartz

Chemistry and Chemical Engineering Faculty Publications

Explaining the evolution of a predominantly homochiral environment on the early Earth remains an outstanding challenge in chemistry. We explore here the mathematical features of a simple chemical model system that simulates chiral symmetry breaking and amplification towards homochirality. The model simulates the reaction of a prochiral molecule to yield enantiomers via interaction with an achiral surface. Kinetically, the reactions and rate constants are chosen so as to treat the two enantiomeric forms symmetrically. The system, however, incorporates a mechanism whereby a random event might trigger chiral symmetry breaking and the formation of a dominant enantiomer; the non-linear dynamics of …


Subcloning And Expression Of Recombinant Human Parathyroid Hormone Rhpth By Fusion Strategy In E.Coli, Sadegh Majdi, Elahe Esfahani, Hossein Amani, Ghasem Najaf pour D, Majid Shahbazi 2014 Rowan University

Subcloning And Expression Of Recombinant Human Parathyroid Hormone Rhpth By Fusion Strategy In E.Coli, Sadegh Majdi, Elahe Esfahani, Hossein Amani, Ghasem Najaf Pour D, Majid Shahbazi

Henry M. Rowan College of Engineering Departmental Research

Osteoporosis is a progressive bone disease that over time, bone mass, and therefore bones strength, is decreased, due to depletion of calcium and bone protein. So, bones become fragile and break easily. The unique ability of human parathyroid hormone (hPTH) as a bone anabolic agent, to increase bone density makes it a promising anabolic agent in the treatment of osteoporosis. Parathyroid hormone secreted by parathyroid chief cells is composed of 84 amino acids act as one of the major hormones maintaining calcium homeostasis. Anabolic agents directly stimulate bone formation and improve the microarchitecture of bone. Hence, they have the potential …


Multiscale Modeling Study Of Methanol Oxidation By Ion-Modified Mdh Enzymes, Purnima Kharidehal 2014 Louisiana Tech University

Multiscale Modeling Study Of Methanol Oxidation By Ion-Modified Mdh Enzymes, Purnima Kharidehal

Doctoral Dissertations

Enzymes have been considered as molecular electrocatalysts due to their extraordinary characteristics such as their ability to accelerate reactions enormously, to operate under physiological conditions, and to produce fewer by-products during a catalytic reaction. However, enzyme based fuel cells have been reported to have power output and stability limitations, which are restricting the use of this kind of fuel cell to small electronic devices. Methanol dehydrogenase (MDH) is one such enzyme, which oxidizes methanol and other primary alcohols to their corresponding aldehydes. The active site of MDH contains a divalent cation (Ca2+), a co-factor pyrrolo-quinoline quinone (PQQ), several amino acids, …


The Effect Of Types Of Alcohol Upon A Support Of Zieglernatta Catalyst To Catalytic Performance, Molecular Weight And Comonomer Composition Distribution, Kanokporn Sinchai 2014 Faculty of Engineering

The Effect Of Types Of Alcohol Upon A Support Of Zieglernatta Catalyst To Catalytic Performance, Molecular Weight And Comonomer Composition Distribution, Kanokporn Sinchai

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research investigated the effect of types of alcohol upon a support of Ziegler-Natta catalyst on ethylene polymerization and ethylene/ 1-hexene copolymerization. Alcohols are the Lewis base, which are used during catalyst preparation. The types of alcohol were divided into two systems. First system is the using ethanol as a Lewis base. Second system is the use of a mixture of ethanol with other alcohols such as isopropanol, 1-butanol, 2-butanol, isobutanol, 1-hexanol, 2-hexanol and cyclohexanol. The results showed that the mixture of alcohols did not change the morphology of catalyst. Moreover, these catalysts exhibited the higher activity than the catalyst …


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