Orientation-Dependent Pseudomorphic Growth Of Inas For Use In Lattice-Mismatched Mid-Infrared Photonic Structures,
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,
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,
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,
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,
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,
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,
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, …
Continuous Ultra-Thin Mos2 Films Grown By Low-Temperature Physical Vapor Deposition,
2014
University of Dayton
Continuous Ultra-Thin Mos2 Films Grown By Low-Temperature Physical Vapor Deposition, Christopher Muratore, Jianjun Hu, Baoming Wang, M. Amanul Haque, John E. Bultman, Michael L. Jespersen, Michael E. Mcconney, R. D. Naguy
Chemical and Materials Engineering Faculty Publications
Uniform growth of pristine two dimensional (2D) materials over large areas at lower temperatures without sacrifice of their unique physical properties is a critical pre-requisite for seamless integration of next-generation van der Waals heterostructures into functional devices. This Letter describes a vapor phasegrowth technique for precisely controlled synthesis of continuous, uniform molecular layers of MoS2 on silicon dioxide and highly oriented pyrolitic graphite substrates of over several square centimeters at 350 °C. Synthesis of few-layer MoS2 in this ultra-high vacuum physical vapor deposition process yieldsmaterials with key optical and electronic properties identical to exfoliated layers. The films are composed of …
Synthesis And Characterization Of Creka-Conjugated Iron Oxide Nanoparticles For Hyperthermia Applications,
2014
University of Rhode Island
Synthesis And Characterization Of Creka-Conjugated Iron Oxide Nanoparticles For Hyperthermia Applications, Anastasia M. Kruse, Samantha A. Meenach, Kimberly W. Anderson, J. Zach Hilt
Chemical, Biomolecular, and Materials Engineering Faculty Publications
One of the current challenges in the systemic delivery of nanoparticles in cancer therapy applications is the lack of effective tumor localization. Iron oxide nanoparticles coated with crosslinked dextran were functionalized with the tumor homing peptide CREKA, which binds to fibrinogen complexes in the extracellular matrix of tumors. This allows for the homing of these nanoparticles to tumor tissue. The iron oxide nanoparticle core allows for particle heating upon exposure to an alternating magnetic field (AMF) while the dextran coating stabilizes the particles in suspension and decreases the cytotoxicity of the system. Magnetically mediated hyperthermia (MMH) allows for the heating …
Mixed Surfactant Systems: Thermodynamics And Applications In Metal Oxide Imprinting,
2014
University of Kentucky
Mixed Surfactant Systems: Thermodynamics And Applications In Metal Oxide Imprinting, Suvid Joshi
Theses and Dissertations--Chemical and Materials Engineering
In this work we study mixtures of cationic surfactant (CTAB) and sugar based surfactant(s) (octyl beta-D-glucopyranoside (C8G1), dodecyl maltoside (C12G2) and octyl beta-D-xylopyranoside (C8X1)) to understand the non-ideal thermodynamic behavior of the mixtures of cationic and non-ionic surfactants in water and synthesis of imprinted materials. The thermodynamics of micellization, mixing and dilution of these systems are studied using Isothermal Titration Calorimetry (ITC) and the experimental data obtained are modeled with a pseudo-phase separation model with non-ideal mixing described by regular solution theory. It is shown that a model accounting for enthalpy of demicellization and enthalpy of dilution based on McMillan-Mayer …
Predicting Propylene Loss With Inferential Model Development Using Design Of Experiments (Doe) And Historical Data,
2014
University of Texas at El Paso
Predicting Propylene Loss With Inferential Model Development Using Design Of Experiments (Doe) And Historical Data, Jeffrey Allen Wheeler
Open Access Theses & Dissertations
Inferential models are a highly researched topic as the science of digital automation becomes more prevalent as information is in abundance. Welldeveloped inferred models can augment the use of analyzers in steady state processing and highly correlated ones can even replace online analytics. The use of design of experiments (DOE) inferred models with historical process data and a rigorous plant simulator can reduce the case study duration while achieving a high degree of accuracy. This paper uses surface response and full factorial models as the first step in model development, and then uses actual historical plant data to create a …
Development Of Nickel Oxide And Manganese Oxide Nanostructured Binary Modified Anodes For Methanol Electro-Oxidation,
2014
The British University in Egypt
Development Of Nickel Oxide And Manganese Oxide Nanostructured Binary Modified Anodes For Methanol Electro-Oxidation, Ghada El-Nowihy
Chemical Engineering
In this investigation, a nanoparticle-based binary catalyst composed of nickel oxide (nano-NiOx) and manganese oxide (nano-MnOx), both were assembled on a platinum substrate, was developed for the direct methanol electro-oxidation (MO) in an alkaline medium. The morphological investigation was performed using field-emission SEM and revealed the electrodeposition of MnOx in a nanorod structure and NiOx in round-shaped nanospheres. The electrocatalytic activity of the modified electrodes towards MO depended critically on the order of deposition of the two oxides. The optimum electrocatalytic activity was obtained at the MnOx/NiOx/Pt electrode (in which nano-NiOx was directly electrodeposited onto the Pt surface followed by …
Reuse Of The Product Obtained On Grinding Kiln Rollers In The Manufacture Of Ceramic Wall Tiles,
2014
The British University in Egypt
Reuse Of The Product Obtained On Grinding Kiln Rollers In The Manufacture Of Ceramic Wall Tiles, Mai H. Roushdy, Shereen K. Amin, Marwa Mohamed, Magdi F. Abadir
Chemical Engineering
The production of ceramic tiles and to a lesser extent flat dinner ware and pottery is increasingly being done by firing in roller kilns. These kilns offer several advantages over conventional tunnel kilns: lower fuel consumption, computer controlled firing curves, low maintenance due to lack of kiln cars, rapid firing cycles of less than one hour and the possibility of shutting down the kiln on short notice.1 One recurrent problem in the operation of such kilns is the periodic need to grind the kiln rollers. These are usually fabricated from high alumina clays and are continuously contaminated by depositions of …
Development Of Nickel Oxide And Manganese Oxide Nanostructured Binary Modified Anodes For Methanol Electro-Oxidation,
2014
The British University in Egypt
Development Of Nickel Oxide And Manganese Oxide Nanostructured Binary Modified Anodes For Methanol Electro-Oxidation, Ghada El-Nowihy
Chemical Engineering
No abstract provided.
Degradable Nanocomposite Preformed Particle Gel For Chemical Enhanced Oil Recovery Applications,
2014
Missouri University of Science and Technology
Degradable Nanocomposite Preformed Particle Gel For Chemical Enhanced Oil Recovery Applications, Paul Tongwa
Doctoral Dissertations
”This work presents two new materials that can be potentially used in conformance control to increase ultimate oil recovery from mature oilfields.
The first product is a degradable nanocomposite preformed particle gel for enhanced in-depth mobility control. Three different types of degradable nanocomposite preformed particle gels were synthesized. These three nanocomposite hydrogels were made using Laponite XLG, Calcium Montmorillonite, and Sodium Montmorillonite nanomaterials. It was observed that after degradation, Laponite XLG nanocomposite hydrogels had the highest post-degradation viscosity (4437 cp), followed by sodium nanocomposite hydrogels (129 cp), and lastly calcium nanocomposite hydrogels (75.5 cp). Thus, degradable Laponite XLG nanocomposite hydrogels …
Semantic Model And Updated Screening Criteria For Polymer Flooding,
2014
Missouri University of Science and Technology
Semantic Model And Updated Screening Criteria For Polymer Flooding, Laila Dao Saleh
Doctoral Dissertations
"Enhanced oil recovery (EOR) processes produce oil that conventional methods leave behind, where interfacial forces, heavy oil viscosity, and reservoir heterogeneity make it difficult to produce. Many EOR methods are available but usually cannot be used at the same time for a candidate reservoir. Therefore, it is important to select the most appropriate EOR process from among the possible techniques. EOR screening criteria have been created using EOR datasets and serve as the first step to compare the suitability of each technique for a specific reservoir. Most of these datasets are based on field data collected from EOR surveys published …
Experimental And Computational Investigation Of Flow Of Pebbles In A Pebble Bed Nuclear Reactor,
2014
Missouri University of Science and Technology
Experimental And Computational Investigation Of Flow Of Pebbles In A Pebble Bed Nuclear Reactor, Vaibhav B. Khane
Doctoral Dissertations
"The Pebble Bed Reactor (PBR) is a 4th generation nuclear reactor which is conceptually similar to moving bed reactors used in the chemical and petrochemical industries. In a PBR core, nuclear fuel in the form of pebbles moves slowly under the influence of gravity. Due to the dynamic nature of the core, a thorough understanding about slow and dense granular flow of pebbles is required from both a reactor safety and performance evaluation point of view.
In this dissertation, a new integrated experimental and computational study of granular flow in a PBR has been performed. Continuous pebble re-circulation experimental set-up, …
Investigating And Modeling Tar-Mats In A Kuwaiti Carbonate Reservoir And Their Role In Understanding Oil Reserves And Recovery Economics,
2014
Missouri University of Science and Technology
Investigating And Modeling Tar-Mats In A Kuwaiti Carbonate Reservoir And Their Role In Understanding Oil Reserves And Recovery Economics, Abdullah Owidah Almansour
Doctoral Dissertations
"Tar-mat columns exist in many carbonate reservoirs in the Middle East. Historically, tar-mats have been thought to impede primary oil extraction, thus necessitating further improved oil recovery (IOR) technology applications. However, this research considers tar-mats as potential sources for unlocking extremely difficult crude oil, less than 5 ⁰API. The main objective of the study was to understand the qualitative physical and chemical properties of extremely viscous tar-mat oil and the quantitative potential of tar-mats to extract difficult oil.
The physical and chemical geneses of the tar-mat oil were analyzed utilizing several experimental geochemical techniques, including rock evaluation pyrolysis, liquid extracts …
A Modified Orthogonal Collocation Method For Reaction Diffusion Problems,
2014
The British University in Egypt
A Modified Orthogonal Collocation Method For Reaction Diffusion Problems, Moustafa A. Soliman, Yousef S. Al-Zeghayer, Abdelhamid M. Ajbar
Chemical Engineering
A low-order collocation method is often useful in revealing the main features such as concentration and temperature profiles and the effectiveness factor for porous catalyst particles. Two modifications are introduced in this paper to make the method more efficient. The first modification is to add an extra collocation point at the center of the particle. It is shown that such extra point introduces a single variable non-linear equation to be solved after obtaining the standard collocation method solution. In the second modification, the polynomial solution obtained from the application of the orthogonal collocation method is transformed to a rational function …
Model-Based Energy Analysis Of An Integrated Midrex-Based Iron/Steel Plant,
2014
King Saud University
Model-Based Energy Analysis Of An Integrated Midrex-Based Iron/Steel Plant, Abdelhamid M. Ajbar, Khalid I. Alhumaizi, Moustafa A. Soliman, Emadadeen Ali
Chemical Engineering
This article presents modeling and simulations of an integrated plant for the production of steel using the direct reduced iron (DRI)=electric arc furnace (EAF) route. In a previous work (Alhumaizi et al., 2012), a comprehensive mathematical model of an iron plant based on MIDREX technology was developed, validated, and simulated. In this article, the model is extended to account for an empirical model of an EAF plant. Numerical simulations were carried out for the effect of different operating parameters of the integrated plant. Useful profiles as well as a summary table were compiled to illustrate the results of the sensitivity …
