Materials Science and Engineering Commons^™

Corrosion Studies Of Stainless Steel Blades, Dhruv S. Kothari

Theses

Corrosion is a subject of interest to interdisciplinary research communities that includes fields of materials science, chemistry, physics, metallurgy and chemical engineering. In order to understand the mechanisms of corrosion and the function of corrosion inhibitors, the reactions at the interfaces between the corrosive electrolyte and a steel surface, particularly at the initial stages of the corrosion process, need to be described. Naturally, these reactions are strongly affected by the nature and properties of the steel surfaces. It is however seen that the majority of recent corrosion and corrosion-inhibition investigations are limited to electrochemical testing, with ex situ analysis of …

Smart Polymeric Temperature Sensors – For Biological Systems, Greenee Anilkumar Sinha

Theses

The damaged brain is vulnerable to increase in brain temperature after a severe head injury. Continuous monitoring of intracranial temperature depicts functionality essential to the treatment of brain injury Many innovations have been made in the biomedical industry relying on electronic implants in treating condition such as traumatic brain injury (TBI) or other cerebral diseases. Hence, a methodical and reliable way to measure the temperature is crucial to assess the patient’s situation. In this investigation, an analysis of various approaches to detect the change in the temperature due to resistance, current-voltage characteristics with respect to time has been evaluated. Also, …

Operating Temperature Of A Solar Thermal Stirling Engine, Spencer Beck

Senior Theses

This paper explores the relationship between the operating temperature and electricity production of a simple heat engine. A Stirling engine was designed and constructed which runs on solar thermal energy collected by a Fresnel lens. The surface area of the solar collector was varied. This manipulated the operating temperature of the Stirling engine in order to measure power output. The mechanical energy from the engine was converted to electricity using a DC motor running in reverse, acting like a generator, in conjunction with an Arduino for data collection. Although adjustments must be made in order to improve the efficiency of …

Thin Film Thermal Deposition At Various Pressures, James Kela Yee Keen Grace

Senior Theses

This research was to verify the hypothesis that resistivity of metal's thin film deposited in a low-pressure environment is the same as its solid material. Thermal Evaporation is a thin film deposition technique in which metal inside a vacuum is evaporated, then deposited onto a surface. Higher quality metal films are deposited when the vacuum pressure is lower. At higher pressures, more air molecules are trapped within the layers of metal, thus increasing scattering sites and increasing the resistance. However, reaching a lower pressure requires more time and effort. In this research, films were deposited at various pressures and resistivities …

Are Solar Panels A Viable Power Source For A Green Energy Vehicle?, Mason C. Adams

Senior Theses

A solar cell powered go-kart has been built and tested. The result shows using solar energy alone cannot meet the requirement of running a regular passenger car. This is due to the limited surface area of the passenger car. This thesis also discusses the operating principles of solar panels, the physics of P type and N type semiconductors, and the formation of the PN junction, as well as the solar current. Modifications of an existing go-kart are described in detail in this thesis. Suggestions for making green vehicles are discussed as well.

Observing Orbital Angular Momentum Transfer From Electron Vortex Beams To Matter, Hannah Devyldere

Senior Theses

It is possible to produce electron beams with non-zero orbital angular momentum. Such beams, known as electron vortex beams, are theoretically able to transfer their orbital angular momenta to matter, causing the matter to rotate. Nanoparticles in an aqueous solution were observed with an electron vortex beam to detect the transfer of orbital angular momentum in a low-friction environment. Observing the transfer of orbital angular momentum to particles in solution is difficult due to the necessity of imaging the particles through a liquid and the random movement of particles in the solution. Thus, orbital angular momentum transfer to matter could …

Ferroelectric-Semiconductor Systems For New Generation Of Solar Cells, Rahmatollah Eskandari

LSU New Orleans Theses and Dissertations

This dissertation includes two parts. In the first part the study is focused on the fabrication of multifunctional thin films for photovoltaic applications. There is no doubt about the importance of transforming world reliance from traditional energy resources, mainly fossil fuel, into renewable energies. Photovoltaic section still owns very small portion of the production, despite its fast growth and vast research investments. New methods and concepts are proposed in order to improve the efficiency of traditional solar cells or introduce new platforms. Recently, ferroelectric photovoltaics have gained interest among researchers. First objective in application of ferroelectric material is to utilize …

Desulfination By 2′-Hydroxybiphenyl-2-Sulfinate Desulfinase Proceeds Via Electrophilic Aromatic Substitution By The Cysteine-27 Proton, Inacrist Geronimo, Shawn R. Nigam, Christina M. Payne

Chemical and Materials Engineering Faculty Publications

Biodesulfurization is an attractive option for enzymatically removing sulfur from the recalcitrant thiophenic derivatives that comprise the majority of organosulfur compounds remaining in hydrotreated petroleum products. Desulfurization in the bacteria Rhodococcus erythropolis follows a four-step pathway culminating in C–S bond cleavage in the 2′-hydroxybiphenyl-2-sulfinate (HBPS) intermediate to yield 2-hydroxybiphenyl and bisulfite. The reaction, catalyzed by 2′-hydroxybiphenyl-2-sulfinate desulfinase (DszB), is the rate-limiting step and also the least understood, as experimental evidence points to a mechanism unlike that of other desulfinases. On the basis of structural and biochemical evidence, two possible mechanisms have been proposed: nucleophilic addition and electrophilic aromatic substitution. Density …

Current Understanding And Future Research Directions At The Onset Of The Next Century Of Sintering Science And Technology, Rajendra K. Bordia, Suk-Joong L. Kang, Eugene A. Olevsky

Publications

Sintering and accompanying microstructural evolution is inarguably the most important step in the processing of ceramics and hard metals. In this process, an ensemble of particles is converted into a coherent object of controlled density and microstructure at an elevated temperature (but below the melting point) due to the thermodynamic tendency of the particle system to decrease its total surface and interfacial energy. Building on a long development history as a major technological process, sintering remains among the most viable methods of fabricating novel ceramics, including high surface area structures, nanopowder-based systems, and tailored structural and functional materials. Developing new …

Nanostructured Dielectric Materials For High Energy Density Multi Layer Ceramic Capacitors, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

A high energy density multilayer ceramic capacitor, having at least two electrode layers and at least one substantially dense polycrystalline dielectric layer positioned therebetween. The at polycrystalline dielectric layer has an average grain size of less than about 300 nanometers, a particle size distribution of between about 150 nanometers and about 3 micrometers, and a maximum porosity of about 1 percent. The dielectric layer is selected from the group including TiO₂, BaTiO₃, Al₂O₃, ZrO₂, lead zirconium titanate, and combinations thereof and has a breakdown strength of at least about 1100 …

Pore Functionalized Pvdf Membranes With In-Situ Synthesized Metal Nanoparticles: Material Characterization, And Toxic Organic Degradation, Hongyi Wan, Nicolas J. Briot, Anthony Saad, Lindell E. Ormsbee, Dibakar Bhattacharyya

Chemical and Materials Engineering Faculty Publications

Functionalized PVDF membrane platforms were developed for environmentally benign in-situ nanostructured Fe/Pd synthesis and remediation of chlorinated organic compounds. To prevent leaching and aggregation, nanoparticle catalysts were integrated into membrane domains functionalized with poly (acrylic acid). Nanoparticles of 16–19 nm were observed inside the membrane pores by using focused ion beam (FIB). This technique prevents mechanical deformation of the membrane, compared to the normal SEM preparation methods, thus providing a clean, smooth surface for nanoparticles characterization. This allowed quantification of nanoparticle properties (size and distribution) versus depth underneath the membrane surface (0–20 μm). The results showed that nanoparticles were uniformly …

Characterizing Structure, Properties, And Deformation In Metallic Glasses And Olivine Using Instrumented Nanoindentation, Kelly Kranjc

McKelvey School of Engineering Graduate Student Theses & Dissertations

Micro- and nanomechanical testing can provide significant insight about the structure, properties, and behavior of materials. These techniques are nondestructive, require only limited amounts of material, and have been known to detect a brittle-to-ductile transition in mechanical behavior due to a size effect. This work utilizes this type of testing to explore fundamental questions about the structure, properties, and behavior of two disparate material systems: metallic glasses and olivine.

Metallic glasses are metallic alloys devoid of any long-range order. Their unique atomic structure imbues them with properties such as a high elastic strain limit, near-theoretical strengths, and the ability to …

An Experimental And Numerical Study Of Nanomechanical Behavior Of Hard/Soft Multilayered Coatings, Benigno Sandoval

Mechanical Engineering ETDs

Multilayer thin film composites, sometimes referred to as nanolaminates, have emerged as an important subset of materials with novel, and often tunable, properties such as high strength, high toughness, and resistance to wear or corrosion. Often fabricated using alternating layers of two or more materials, these multilayer thin film coatings are typically expensive and time intensive to fabricate and characterize and exhibit novel responses to nanomechanical testing such as plasticity during unloading. This thesis explores the nanoindentation response of hard/soft multilayer coatings through examination of the optical coating Al/SiC and similar coating Al/SiO2. Instrumented indentation was used to study single …

Real-Time Atomistic Observation Of Structural Phase Transformations In Individual Hafnia Nanorods, Bethany M. Hudak, Sean W. Depner, Gregory R. Waetzig, Anjana Talapatra, Raymundo Arroyave, Sarbajit Banerjee, Beth S. Guiton

Chemistry Faculty Publications

High-temperature phases of hafnium dioxide have exceptionally high dielectric constants and large bandgaps, but quenching them to room temperature remains a challenge. Scaling the bulk form to nanocrystals, while successful in stabilizing the tetragonal phase of isomorphous ZrO₂, has produced nanorods with a twinned version of the room temperature monoclinic phase in HfO₂. Here we use in situ heating in a scanning transmission electron microscope to observe the transformation of an HfO₂ nanorod from monoclinic to tetragonal, with a transformation temperature suppressed by over 1000°C from bulk. When the nanorod is annealed, we observe with …

Understanding Photovoltaic Properties Of Pbs Quantum Dot Solids Via Solution Contacting, Vitalii Dereviankin, Erik Johansson

Student Research Symposium

Photovoltaic (PV) devices based on PbS quantum dot (QD) solids demonstrate high photontoelectron conversion yields. However, record power conversion efficiency remain low, in part due to small photovoltages, which in turn are affected by both bulk and interfacial defects. Their relative impacts on limiting the photovoltaic performance of QD solids are not known. Interfacial defects can be formed when contacting a semiconductor and may dominate the semiconductor/metal or metaloxide junction properties. The objective of this study is to explore whether electrochemical contacting using liquid electrolytes provides means of contacting QD solids without introducing interfacial defects. We have initially focused on …

Speculations On A City For Mars, Edouard Terzis

School of Architecture - Theses

This thesis proposes the reinterpretation of architectural forms as the index of the constitution of the idea of the city. “Speculations on a City on Mars” is paradoxical in a sense as it superposes both the managerial representation of a city, that is Zoning, along with the speculative aspect of an extra-terrestrial city.

Single Use Droplet Based Microfluidics – Screening Tools For Biotechnology And Life-Sciences, Alexander Groß, Jialan Cao, Stefen Schneider, J.M. Köhler, Thomas Henkel, Martin Roth, Mark Kielpinsky, Alexander Mendel

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

In the recent years droplet-based microfluidic techniques were developed and used for various screening purposes mainly in the field of life-sciences and biotechnology. Therefore, droplet volumes in a range from pL to μL were used and different technology platforms were necessary to produce the required fluidic devices which made of various materials. Traditionally, lithography combined with etching processes were used to produce precise glass or silicon devices. But, hot embossing and injection molding techniques are better suited for the production of single use devices. Recently, 3D-printing technologies are under development for the generation of individual costumes made microfluidic devices in …

3-D Printing Open-Source Click-Muac Bands For Identification Of Malnutrition, Ross Michaels, Joshua M. Pearce

Department of Materials Science and Engineering Publications

No abstract provided.

Of Sut And Stainless, Manuel Carrondo

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

No Abstract, Please Click And See The Presentation.

Roll-To-Roll Pilot Line For Large-Scale Manufacturing Of Microfluidic Devices, Martin Smolka, Anja Haase, Ursula Palfinger, Dieter Nees, Ladislav Kuna, Jan Hesse, Barbara Stadlober, Sascha. Geidel, Jörg Nestler, Nikolaus Ladenhauf, Andoni Rodriguez, Florian Hasenöhrl, Martin Eibelhuber, Max Sonnleitner, Guggi Kofod, Dan Kofoed, Jan Kafka, Isbaal Ramos, Manuel W. Thesen, Mirko Lohse, Ana Ayerdi, Nerea Briz

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

Roll-to-roll (R2R) technologies with roller-based nanoimprinting methods enable manufacturing of highly cost-effective and large-scale sheets of flexible polymer film with precise structures on a micro- and nanoscale 1. Areas that can benefit strongly from such large scale technologies are microfluidics, biosensors, and lab-on-chip products for point of care diagnostics, drug discovery and food control. Here, R2R fabrication could greatly reduce production costs and increase manufacturing capacity with respect to currently used products. A pilot line with this technology is investigated in the European Horizon 2020 project R2R Biofluidics and its capabilities are tested on two Demonstrators: - Demonstrator 1: In-vitro …

Protein-Specific Empirical Model Of Protein Adsorption On Surfaces, Dan Nicolau

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

Predicting protein adsorption from solution to a surface is an important problem in biomedicine and related fields. Despite constant attention in the literature, it is not currently possible to predict quantitatively the amount of adsorbed protein given environment, protein and surface parameters. We present a purely empirical approach to predict protein adsorption using a linearly piecewise model with breakpoint, based on progress in the understanding and quantification of physico-chemical properties on protein molecular surfaces. This model is capable of accounting for over 90% of the variance in the data, despite the fact that the adsorption data spans over three orders …

On The “Fate Of Leachables” In Biopharmaceutical Up-Stream And Down- Stream Processes, Armin Hauk, Ina Pahl, Roberto Menzel, Samuel Dorey, Isabelle Uettwiller

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

Single use systems (SUS), based on polymeric materials, are widely used in the biopharmaceutical manufacturing. Compounds potentially migrating from the polymeric materials into the production process at various stages as leachables can either negatively influence the production process performance (e.g. inhibit cell growth) or can contribute to process related drug impurities, which may potentially have an effect on product quality and/or patient safety. Today, the concept of investigating leachables is mainly focused on the measurement of extractables under worst case- or simulation-conditions plus their assessment including an interpolation towards potential leachables. In particular, in the frame of this assessment of …

Tie Layer Technology For Multilayer Coextrusion Of Single-Use Biopharma Bags, Barry A. Morris

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

The needs of the demanding biopharma processing bag, such as barrier, toughness and heat sealability, cannot be met by any one polymer. As a result, multiple layers of different polymers, each playing its role in meeting the design requirements, are combined in coextrusion or lamination. Most of the polymers used in these layers do not naturally adhere to each other in the film making or lamination process without tie layers. Tie layers are polymer resins designed to provide adhesion between specific polymers in a given film manufacturing process. In coextrusion, the polymer layers are brought together in the melt state. …

Influence Of Γ-Irradiated Biopharmaceutical Films, Samuel Dorey, Fanny Gaston, Magali Barbaroux,, Nathalie Dupuy, Sylvain R.A. Marque

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

Preventing cross-contamination, saving costs and increasing configuration flexibility make the adoption of single-use technologies very attractive for the biopharmaceutical industry. The integrity and the security of bags are due to appropriate flexible and barrier polymeric materials, such as polyethylene (PE) or ethylene vinyl acetate (EVA) and polyethylene-co-vinyl alcohol (EVOH), which are barrier to water vapor and oxygen, respectively. Conventional stainless steel tanks are sterilized by steam sterilization by the end-users, whereas plastic containers are sterilized by gamma-irradiation before delivery. The major advantage of radio-sterilization is the penetration power of the γ-radiation. It is known that γ -sterilization of polyolefin based …

The Journey Of A Polymer Producer To Support Customers E&L Needs, Jerome Vachon

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

In the view of SABIC’s ambitions to grow in the Healthcare applications market, a clear understanding of customers’ challenges and problems with respect to Extractables and Leachables is crucial. In addition to ensuring high quality products and compliance with standard regulations, material suppliers must also have a deep knowledge of their product chemistries for specific healthcare applications. Responding to our customers’ needs when performing their own material toxicological assessment, SABIC has continued to develop and share deeper insights into E&L. A growing involvement of SABIC to develop a true E&L knowledge base, from Research to Marketing, has thus been taking …

Xdr-500 Mo—Single-Use Fermentor For Microbial Processes, Jozsef Vasi, Andreas Castan, Sandeep Kristiansson

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

Single-use bioreactors are well-established in production of biopharmaceuticals in mammalian expression systems. However, a similar technology breakthrough for microbial/yeast-based productions is still awaiting due to the unique requirements associated with such high-cell density cultivations, including high oxygen transfer capacity and efficient heat removal. Here, we present the single-use Xcellerex™ XDR-500 MO stirred-tank fermentor system specifically designed for microbial/yeast applications. The performance of the fermentor was evaluated using an E. coli fed-batch process producing a domain antibody (dAb) as a model system. The process was originally developed for a lab-scale conventional stainless steel system. This work describes the transposition and scale-up …

Effect Of Agitation On Protein Aggregation In Vials Made From Glass Or Plastics, Birgit Mueller-Chorus, Erica Tullo, Vinod Vilivalam, Lloyd Waxman

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

The increasing use of proteins as therapeutics including monoclonal antibodies has focused attention on the need to maintain the stability of these labile molecules during both storage and shipment. The degradation of therapeutic proteins can arise from aggregation and adsorption in primary containers, as well as from exposure to leachables, and chemical damage due to exposure to oxygen or light. Since vials continue to be used as primary containers for multiple-use applications, including vaccines and lyophilized drug products, we have compared the effect of mechanical stress on protein aggregation in vials made of glass versus vials made of the plastic …

Particulate Contamination In Single Use Systems: Measurement Challenges, Klaus Wormuth, Fanny Gaston, Mathieu Labedan

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

In conventional biopharmaceutical processes using stainless steel components, the pharmaceutical manufacturer is responsible for process cleanliness. However for single use systems, the pharmaceutical manufacturer “outsources” process cleanliness to the manufacturer of the single use systems, since no rinsing or cleaning occurs prior to implementation. Especially critical applications such as final fill and finish or aseptic processes demand a high degree of cleanliness with respect to particulate contamination. Although single use component assembly occurs in carefully controlled cleanroom environments, risks arise for particulate contamination from incoming components, cutting and welding operations, and human activity during manually intensive assembly processes. While visual …

Conference Program, Ekta Mahajan, Gary Lye, Regine Eibl-Schindler

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

No abstract provided.

Characterization Of Silicone Tubing – Effect Of Pressure And Irradiation On Tubing Diameter, Lise Tan-Sien-Hee, Csilla Kollar, Andrew Diehl, Ernie Jenness, Pietro Perrone

Single-use Technologies II: Bridging Polymer Science to Biotechnology Applications

A Single-Use assembly or system consists of numerous flexible components connected together via heat seals, overmolds or mechanical fasteners. The integrity (e.g. leak assurance) of such a system is dependent on the internal surface being continuously sealed and free of disconnects between the various components. The diameter of the flexible tubing during manufacture of the assemblies and the tubing expansion at operational pressures are important characteristics to know. Understanding these factors can help in the design of assemblies that maintain their integrity throughout their use at operating conditions. The aim of the study was to characterize four different tubing types …