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Fabrication, Characterization And Application Of Zinc Oxide And Zinc Magnesium Oxide Nanostructures, Abdiel Rivera

Doctoral Dissertations

Zinc oxide is a wide bandgap semiconductor with relatively large exciton energy of 60 meV, and longitudinal optical phonon energy of 72 meV. ZnO can be grown in any nanostructure (nanoribbons, nanowires, nanorods, films, core-shell, among others), under any growth condition (metal-organic chemical vapor deposition (MOCVD), molecular beam epitaxial (MBE), hydrothermal, radio-frequency sputtering, sonochemical, etc) to be implemented in a variety of applications. For instance, by adding Mg to ZnO, the energy band separation increases and shift to a lower wavelength. Using ZnMgO, in the form of vertical nanowires, can improve the resolution of solar-blind UV-detectors. Nevertheless, the sol-solubility of …

Assessment Of Summer Drought Tolerance And Persistence Of Some Grass Cultivars In Algerian Semi Arid Conditions, Mohamed Mefti, Hamena Bouzerzour, Abderrezak Chebouti, Aissa Abdelguerfi

IGC Proceedings (1997-2023)

Stress-tolerant forage resources are increasingly needed for the environmental and economic sustainability of extensive Mediterranean livestock systems. Perennial forages belonging to two species: Festuca arundinacea Schreb. (tall fescue) and Dactylis glomerata L. (cocksfoot) can be a valuable alternative to annuals, if they can survive across successive summer droughts. Poor persistence of sown perennial pasture grasses is a problem in regions of the World with Mediterranean climates where the most stressful, life threatening season is a summer characterised by long and often severe droughts with high temperatures. The objective of this study is to compare 14 grass cultivars in an Algerian …

Neutron Diffraction Study Of Multiferroic 0.6nife2o4/0.4batio3 Composite, Engkir Sukirman, Yosef Sarwanto, Syahfandi Ahda, Andon Insani

Makara Journal of Technology

Neutron diffraction study on the 0.6NiFe2O4/0.4BaTiO3 multiferroic composite has been carried out. The 0.6NiFe2O4/0.4BaTiO3 multiferroic composites have been synthesized by solid reaction method. In this study, 20 g of BaTiO3 (BTO) and 20 g of NiFe2O4 (NFO) compounds were prepared from the powder raw materials of BaO3 and TiO2 for BTO, and NiO and Fe2O3 for NFO. Furthermore, both BTO and NFO were each crushed for 5 hours using High Energy Milling (HEM). Then the BTO and NFO were calcined in the furnace at 950 °C/5 hours and 900 °C/5 hours, respectively. Both NFO and BTO precursors were manually mixed …

Nanoscale Optical And Correlative Microscopies For Quantitative Characterization Of Dna Nanostructures, Christopher Michael Green

Boise State University Theses and Dissertations

Methods to engineer nanomaterials and devices with uniquely tailored properties are highly sought after in fields such as manufacturing, medicine, energy, and the environment. The macromolecule deoxyribonucleic acid (DNA) enables programmable self-assembly of nanostructures with near arbitrary shape and size and with unprecedented precision and accuracy. Additionally, DNA can be chemically modified to attach molecules and nanoparticles, providing a means to organize active materials into devices with unique or enhanced properties. One particularly powerful form of DNA-based self-assembly, DNA origami, provides robust structures with the potential for nanometer-scale resolution of addressable sites. DNA origami are assembled from one large DNA …

New Modified Weibull Distribution: Moment Properties And Bayes Analysis, M. A. Khan, Richa Srivastava

Journal of Statistics Applications & Probability

The objective of the study is two fold. The first one is to give some recurrence relations satisfied by single and product moments of Generalized Record Values (GRV) from New Modified Weibull Distribution (NMWD). These relations are derived for moments of upper record values. Further, conditional expectation is used to characterize the New Modified Weibull Distribution. The second objective is to give complete Bayesian analysis of the New Modified Weibull Distribution for parameter estimation. We are proposing Markov chain Monte Carlo simulation with hybrid strategy for the same.

Characteristic Studies On The Biochars Produced By Hydro-Thermal And Steam Gasification Of Canola Hull And Canola Meal Fuel Pellets, Franco Berruti, Sonil Nanda, Ajay K. Dalai, Janusz A. Kozinski

Bio-Char II: Production, Characterization and Applications

Biochars, based on their production process and biomass precursor, can have a broad range of structural, compositional, chemical, and physical properties. These properties are important for identifying the biochar performance and stability in further applications. Non-food biomass has a great potential to produce biochars. Two inherent agricultural biomasses from Canadian prairies including canola hull and canola meal were used for the production of fuel pellets. This study provides information on the specific features of biochars produced by steam and hydro-thermal gasification of these fuel pellets compared with those of well-known pyrolysis biochars. For steam gasification, the steam to biomass ratio …

Synthesis And Characterization Of Dinitro Pentamethylene Tetramine (Dpt), M. M. Seleet, S. A. Hassanien, M. A. Radwan, M. A. Sadek

Chemical Engineering

Preparation of dinitro pentamethylene tetramine (DPT) through the action of nitrating mixture formed of ammonium nitrate and fuming nitric acid on hexamine in presence of acetic acid, acetic anhydride and p-formaldehyde has been carried out. DPT was also prepared from hexamine dinitrate which is an important intermediate appears through preparation of DPT from hexamine directly. Prepared DPT was purified and then characterized through the determination of melting point, element test, FTIR spectrometry, UV spectrometry, and high performance liquid chromatography "HPLC". The obtained results were reliable and consistent with the literature.

Cheops: The Esa Mission For Exo-Planets Characterization Ready For Launch, Joel Asquier, Nicola Rando, Carlos Corral Van Damme, Francesco Ratti, K. Isaak, R. Southworth, F. Safa, C. Broeg, T. Beck, W. Benz, A. Borges, D. Cortes, R. Palacios

Small Satellite Conference

The European Space Agency (ESA) Science Programme Committee (SPC) selected CHEOPS (Characterizing Exoplanets Satellite) in October 2012 as the first Small-class mission (S1) within the Agency’s Scientific Programme. It is considered as a pilot case for implementing “small science missions” in the agency with the following requirements: science driven mission selected through an open Call; an implementation cycle, from the Call to launch, drastically shorter than for Medium-class (M) and Large-class (L) missions; a strict cost-cap to ESA, with possibly higher Member States involvement than for M or L missions.

The CHEOPS mission is devoted to the characterization of known …

Characterization Of Semi-Autonomous On-Orbit Assembly Cubesat Constellation, John M. Gregory, Jin S. Kang, Michael Sanders, Dakota Wenberg, Ronald M. Sega

Small Satellite Conference

Demand for more complex space systems is ever increasing as the scale of the future missions expands. Accordingly, much focus has been given recently to innovations in on-orbit assembly and servicing to ensure those missions are executed in a time-efficient manner. The past on-orbit servicing demonstrations have involved large satellites that were designed to dock/berth and service specific client satellites, and did not leverage the current advancements in small satellite technology. The U.S. Naval Academy (USNA) is contributing to advancing the onorbit servicing and assembly technology with a next-generation robotic arm Intelligent Space Assembly Robot (ISAR) system, which is envisioned …

A Novel Technique To Characterize The Surface Hydrophobicity Of Proteins Using Inverse Liquid Chromatography, Dilip Sethi, Sarah Hedberg, Daryl Williams

Biological and Pharmaceutical Complex Fluids III: Protein Self-Assembly, Rheology and Interfacial Properties

This work presents a novel technique to characterize the surface hydrophobicity and other surface properties of proteins. The surface properties of industrial and therapeutic proteins are key to understanding their behavior in-situ, in the laboratory and in processes. Protein surface hydrophobicity is a marker for three dimensional structure, stability and function. Inverse Liquid Chromatography of Proteins (ILCP) with small molecule hydrophobic probes can be used to obtain direct measurements of the surface hydrophobicity of column resin-bound proteins using changes in probe retention behavior. The dimensionless hydrophobicity factor (H_f) for Lysozyme and BSA was obtained with changing pH …

Comparison Among Technical And Milled Wood Lignins Through Principal Component Analysis Of Ftir Spectra, Manuel Garcia-Perez, Erika Bartolomei, Yann Le Brech, Anthony Dufour, Evan Terrell

Pyroliq 2019: Pyrolysis and Liquefaction of Biomass and Wastes

With the growth of biomass processing in biorefineries, there is an increasing need to develop rapid and simple methods for biomass characterization. One important component of biomass that is of signification interest in pyrolysis and liquefaction research is lignin, which is the world’s predominant source of renewable aromatic carbon. Due to its complex, heterogeneous nature and distinct variations among different biomass feedstocks, the characterization of lignins presents a unique challenge. In this study, we will show that clear divisions and comparisons can be made among a variety of lignins based on their FTIR spectra quantitatively assessed through principal component analysis …

Follow-Up And Kinetic Model Selection Of Dinitro Pentamethylene Tetramine (Dpt), Hany A. Elazab Dr

Chemical Engineering

The Synthetic route of Cyclotetramethylene Tetramine is implemented through the reaction of hexamine and nitrating mixture that is formed as a result of a reaction between ammonium nitrate and fuming nitric acid. The reaction medium includes acetic acid, acetic anhydride and p-formaldehyde. This synthetic pathway is relatively long and both of hexamine dinitrate and Dinitro Pentamethylene Tetramine (DPT) are considered as the two main intermediate compounds. The former compound (hexamine dinitrate) was prepared, purified, and then characterized. Conversion of hexamine dinitrate into DPT has been followed up experimentally at different temperatures. Various factors including temperature and time has been investigated. …

Follow-Up And Kinetic Model Selection Of Dinitro Pentamethylene Tetramine (Dpt), Hany A. Elazab, M. M. Seleet, Said M.A. Hassanein, M. A. Radwan, M. A. Sadek

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Synthetic route of Cyclotetramethylene Tetramine is implemented through the reaction of hexamine and nitrating mixture that is formed as a result of a reaction between ammonium nitrate and fuming nitric acid. The reaction medium includes acetic acid, acetic anhydride and p-formaldehyde. This synthetic pathway is relatively long and both of hexamine dinitrate and Dinitro Pentamethylene Tetramine (DPT) are considered as the two main intermediate compounds. The former compound (hexamine dinitrate) was prepared, purified, and then characterized. Conversion of hexamine dinitrate into DPT has been followed up experimentally at different temperatures. Various factors including temperature and time has been investigated. …

“To Be Men, Not Destroyers”: Developing Dabrowskian Personalities In Ezra Pound’S The Cantos And Neil Gaiman’S American Gods, Michelle A. Nicholson

University of New Orleans Theses and Dissertations

Kazimierz Dabrowski’s psychological theory of positive disintegration is a lesser known theory of personality development that offers an alternative critical perspective of literature. It provides a framework for the characterization of postmodern protagonists who move beyond heroic indoctrination to construct their own self-organized, autonomous identities. Ezra Pound’s The Cantos captures the speaker-poet’s extensive process of inner conflict, providing a unique opportunity to track the progress of the hero’s transformation into a personality, or a man. American Gods is a more fully realized portrayal of a character who undergoes the complete paradigmatic collapse of positive disintegration and deliberate self-derived self-revision …

Phenolate Derivatives Of Octanuclear Iron-Oxo-Pyrazolato Complexes; Enantiomeric Resolution Of T-Symmetry Species, Konstantinos Lazarou

FIU Electronic Theses and Dissertations

Octanuclear ferric complexes involving achiral phenolates of the general formula [Fe₈(μ-O)₄(μ-pz)₁₂(R-C₆H₄O)₄], (R = 4-NO₂, 4-CN, 4-F, 4-Cl, 4-I, 4-CH₃O, and 3-NO₃), where synthesized and characterized by single crystal X-ray crystallography, elemental analysis, ¹H-NMR, UV-Vis, IR, ⁵⁷Fe Mössbauer spectroscopy and electrochemical methods (cyclic and differential pulse voltammetry). Results indicate that the nature of the phenolate substituents allows the fine tuning of the spectroscopic data of the compounds.

Subsequently, this project focused on the resolution of the racemic …

Upper Record Values From Extended Exponential Distribution, Devendra Kumar, Sanku Dey

Journal of Modern Applied Statistical Methods

Some recurrence relations are established for the single and product moments of upper record values for the extended exponential distribution by Nadarajah and Haghighi (2011) as an alternative to the gamma, Weibull, and the exponentiated exponential distributions. Recurrence relations for negative moments and quotient moments of upper record values are also obtained. Using relations of single moments and product moments, means, variances, and covariances of upper record values from samples of sizes up to 10 are tabulated for various values of the shape parameter and scale parameter. A characterization of this distribution based on conditional moments of record …

Modeling And Characterization Of A Ring-Resonator Based Silicon Photonic Sensor On Silicon-On-Insulator (Soi), Gwangho Choi

Graduate Theses - Physics and Optical Engineering

The purpose of this work is to build silicon photonic devices and verify their functionalities. In particular, the structure of a ring resonator (RR) is analyzed and applied to various silicon photonic application in sensing. Silicon waveguides, grating couplers, directional couplers, and RRs are fabricated on the silicon-on-insulator (SOI) wafer. Geometrical parameters and optical properties of the silicon devices are studied and also applied to the design of the aforementioned devices. The waveguide dimensions and, optical properties of the silicon waveguide such as dispersion and effective-index are examined. The RRs are made of a series of straight and bent waveguides …

Model-Based Medium-Voltage Induction Machine Insulation Material Characterization, Arshiah Yusuf Mirza

Master's Theses

The voltage and frequency handling capability of power converter modules have tremendously increased with the penetration of wide-band-gap (WBG) semiconductor technology in power electronics. However, very little is known about the effect of the high-voltage high-frequency transients exerted by WBG power electronics on insulation materials. This thesis investigates the effect of high-voltage, high-frequency transients on aging and breakdown characteristics of insulation materials. The aim of this research was to analyze this breakdown and develop the behavioral model of the breakdown time when such insulation materials are used in inverter-fed medium-voltage induction machines. As a part of this research, a series …

Characterization Of Graphene Oxide, Harish Kumar

Doctoral Dissertations

The conversion of graphite to graphene oxide (GO) is an effective and widely used method for solubilizing and exfoliating graphite. However, the oxidation is not uniform, and wide variations in the degree of oxidation exist between and within batches of GO. In this dissertation, we introduce an approach to both quantify the global degree of oxidation in GO and to separate GO into fractions, each with more uniform extents of oxidation. Using the formation of GO-stabilized oil-in-water emulsions, GO is separated into an emulsion fraction and a water fraction. The results find that the GO sheets that stabilize the emulsion …

Characterization And Optimization Of A Propeller Test Stand, Colin Bruce Leighton Benjamin

Mechanical & Aerospace Engineering Theses & Dissertations

In recent history, there has been a rapid rise in the use of drones, and they are expanding in popularity each year. The widespread use and future capabilities of these unmanned aerial vehicles (UAVs) will call for increased study and classification of propellers to maximize their performance. As a result, it is necessary to have continuity in the development, maximization, and optimization of propeller test stand’s capability to collect accurate and precise measurements. It is of significant advantage to have the capability of accurately characterizing a propeller based on its thrust and torque. In this study, a propeller test stand …

3,7-Dinitro-1,3,5,7-Tetraazabicyclo[3,3,1]Nonane (Dpt): An Important Intermediate In The Synthesis Route Of One Of The Most Powerful Energetic Materials (Rdx/Hmx), Hany A. Elazab Dr

Chemical Engineering

Synthesis of Cyclotetramethylene Tetramine through the action of nitrating mixture formed of ammonium nitrate and fuming nitric acid on hexamine in presence of acetic acid, acetic anhydride and p-formaldehyde has been proven. The pathway is relatively long and Hexamine Dinitrate and Dinitro Pentamethylene Tetramine (DPT) are two of the main intermediate compounds. The former was prepared, purified, and then characterized. Conversion of this compound into the latter has been followed up experimentally. Herein, we report the Preparation of Dinitro Pentamethylene Tetramine (DPT) from Hexamine Dinitrate - as an alternative synthetic route - which is an important intermediate appears through preparation …

Characterization Of Mechanical Properties Of Thin-Film Li-Ion Batteryelectrodes From Laser Excitation And Measurements Ofzero-Group Velocity Resonances, Jing Yao

Theses and Dissertations

The mechanical properties of thin-film Li-ion battery electrodes are controlled by the micro structure of the constituent materials. In this work, a non-contact and non-destructive measurement of the mechanical properties of electrode films is performed by measurement of zero group velocity (ZGV) resonances. The ZGV Lamb wave modes of a solid bi-layer consisting of a thin metallic layer and a thin compliant coating layer are shown to be dependent on the Young's moduli, thicknesses, densities and Poisson ratios of the layers. Theoretical models are used to quantify the sensitivity of the ZGV resonances to changes in mechanical properties. Experimental ZGV …

Characterization, Source Apportionment And Health Analysis Of Air Pollutants In India, Hao Guo

LSU Doctoral Dissertations

In recent years, severe pollution events occurred frequently in India, which are of significant concern of the public. However, limited studies have been conducted to understand the formation, sources and health effects of high pollution levels and the information for design of effective control strategies is urgently needed. First, criteria air pollutants data at 10 sites for 2017 in Delhi were analyzed to understand the current pollution status. The results show that annual fine particulate matter (PM_2.5) concentrations exceeded the National Ambient Air Quality Standards (NAAQS), India of 60 µg/m³ at all sites. Source-oriented versions of the …

Frequency Domain Characterization And Performance Bounds Of Alms Loop For Rf Self-Interference Cancellation, Anh Tuyen Le, Le Chung Tran, Xiaojing Huang, Y J. Guo, J (Yiannis) Vardaxoglou

Faculty of Engineering and Information Sciences - Papers: Part B

Analog Least Mean Square (ALMS) loop is a promising method to cancel self-interference (SI) in in-band fullduplex (IBFD) systems. In this paper, the steady state analyses of the residual SI powers in both analog and digital domains are firstly derived. Eigenvalue decomposition is then utilized to investigate the frequency domain characteristics of the ALMS loop. Our frequency domain analyses prove that the ALMS loop has an effect of amplifying the frequency components of the residual SI at the edges of the signal spectrum in the analog domain. However, the matched filter in the receiver chain will reduce this effect, resulting …

Materials Characterization In The Development Of Combustion-Based Methods For Synthesis Of Niobium Silicides, Edgar Maguregui

Open Access Theses & Dissertations

The use of characterization techniques is essential for a better understanding of novel manufacturing processes and for investigating how the process parameters affect the products. Mechanically activated self-propagating high-temperature synthesis (MASHS) is an attractive method for the production of high-temperature structural materials. In the present work, it was used to fabricate Nb5Si3 compound and Nb5Si3/Nb composites. It has been shown that for mechanical activation of Nb/Si mixtures, a planetary ball mill is more effective than a shaker ball mill used in prior research on MASHS of Nb5Si3. The influence of mixture composition and experimental parameters, such as milling time and …

Low-Valent Synthons Of Titanium : Investigations On Structure-Reactivity Relationships, Rolando Aguilar

Open Access Theses & Dissertations

Strategies for the functionalization of abundant, small molecules into products with added value provide a powerful approach to address environmental sustainability issues. Dinitrogen (N2), and carbon oxides (CO, CO2), are examples of the ample, yet, underutilized atmospheric feedstock of nitrogen and carbon building blocks to produce a variety of chemicals. Although, potentially valuable, small molecules are inert under most conditions, and as such, their industrial activation often requires heterogeneous catalysts operated under high pressures (200 atm) and temperatures (450-600 ºC).

To this end, great efforts in synthetic inorganic chemistry have been devoted to the generation of well-defined and highly reactive …

Improving The Delivered Specific Impulse Of Composite Rocket Propellant Through Alteration Of Chemical Composition: Methodology And Parameters For Characterization Of Propellant And Validation Of Simulation Software Common To The Amateur Rocketry Community, Isaac O'Brien, Austin Ryan

Williams Honors College, Honors Research Projects

In this study, two solid composite rocket propellants were designed utilizing ProPEP, a rocket propellant formulation software common in the amateur and hobby rocketry communities. The two propellants were designed to optimize specific impulse relative to a literature propellant designed by 1020 Research Labs. The literature propellant was also tested in order to validate the design of experiment as well as the mixing and testing procedures. All three propellants, which includes the literature propellant RCS-P, and the two novel propellants AKR-P1 and AKR-P2 were characterized with static tests. The results of the static tests provide data on propellant performance and …

Characterization Of Bone Surface Modifications On An Early To Middle Pleistocene Bird Assemblage From Mata Menge (Flores, Indonesia) Using Multifocus And Confocal Microscopy, Hanneke J.M Meijer, Francesco D'Errico, Alain Queffelec, Iwan Kurniawan, Erick Setiabudi, Indra Sutisna, Adam R. Brumm, Gerrit D. Van Den Bergh

Faculty of Science, Medicine and Health - Papers: Part B

Island Southeast Asia (ISEA)is a key region for the study of human evolution. New fossil and archaeological evidence, from several islands, suggests an Early to Middle Pleistocene colonisation date by hominins. A taphonomic framework, however, such as that exists for Africa, is currently lacking, and taphonomical studies of ISEA vertebrate assemblages are very limited. In this paper, we apply multifocus and confocal microscopy to surface modifications on an Early to Middle Pleistocene avian assemblage from Mata Menge, in the So'a Basin of central Flores, Indonesia, with the aim of characterizing material and testing the relevance of 3D reconstructions to study …

The Production And Characterization Of Chitosan Based Microgels Using A Novel Microfluidic Device To Promote Cell Survival, Kaileen Shevchuk

Williams Honors College, Honors Research Projects

The purpose of this project is to synthesize and characterize perfluorocarbon modified methacrylamide chitosan (MACF) microgels produced with the use of a capillary-based microfluidic device. Since cell survival and development is highly related to particles physical properties, analysis of microgels set out to determine the particle’s physical properties. I hypothesize that the viscosity of the MACF polymer as well as the amount of photo initiator influence the physical properties of synthesized particles and as a result can generate particles with various features for cell culture in terms of shape, size, charge and swelling abilities. This hypothesis was validated through the …

Phenotypic Characterization And Differentiation Of Mesenchymal Stem Cells Originating From Adipose Tissue, Ece Çerçi̇, Hati̇ce Erdost

Turkish Journal of Veterinary & Animal Sciences

Stem cells are known as undifferentiated cells that are capable of divisions and self-renewal over an extended period. Adipose tissue-derived mesenchymal stem cells (ADSCs) are known to differentiate into many different organ and tissue cells. The purpose of this study was to characterize adipose tissue-derived mesenchymal stem cells in detail based on the expression status of certain surface markers and differentiation stages for clinical and laboratory applications. The migrating phase and mitotic property of the cells from adipose tissue were assessed under a microscope. Cell counting was performed during the first, second, and third passages. The cells were differentiated into …