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Full-Text Articles in Engineering

The Effects Of Ni Nanoparticle Additives On Thermodynamic Events In Commercial Ni Based Braze Alloy, Cody Lesage May 2024

The Effects Of Ni Nanoparticle Additives On Thermodynamic Events In Commercial Ni Based Braze Alloy, Cody Lesage

Theses and Dissertations

The use of nanomaterials in brazing applications has become more prevalent with the increasing understanding of the underlying thermodynamic events during the brazing process. Their influence on an already modified system, via melting point depressants, is not well understood. In this investigation, the influence of both nanoparticle size and weight percent of nanoparticle additive are studied to determine the relationship on thermodynamic events. Differential scanning calorimetry was used to measure the energy flow throughout the system during the brazing events. Scanning electron microscopy was used qualitatively to view the resulting brazed region. The results indicate a direct relationship between nanoparticle …

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Pulsed Dielectric Breakdown And Permittivity Characterization Of Composite Solid Insulators In Pulsed Power Systems, Shawn T. Scoggin Jan 2024

Pulsed Dielectric Breakdown And Permittivity Characterization Of Composite Solid Insulators In Pulsed Power Systems, Shawn T. Scoggin

Electrical Engineering Dissertations

In high voltage pulsed power systems, liquids and gases are often used as insulating materials because they offer high breakdown strengths, conform around complex geometries, and are self-healing, but they can introduce significant engineering challenges and restrictions when it comes to implementing them. Solid dielectrics can be desirable for improving the maintenance requirements, shelf life, and power/energy density metrics associated with insulating high voltage pulsed power systems, however they possess design challenges of their own. Solid dielectrics are not self-healing and can be difficult to manufacture, especially around complex geometries. Epoxy dielectrics are of high interest because of their naturally …

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Engineering Hybrid Colloidal Systems Formed By Charge-Driven Assembly Between Spherical Soft Nanoparticles And Discotic Nanoplatelets, Gelareh Rezvan Oct 2023

Engineering Hybrid Colloidal Systems Formed By Charge-Driven Assembly Between Spherical Soft Nanoparticles And Discotic Nanoplatelets, Gelareh Rezvan

Theses and Dissertations

Soft matter, a fascinating class of materials, holds a paramount significance in the realm of material design and engineering. Within this broad category, colloidal gels with their unique characteristics have drawn tremendous attention in a variety of applications, spanning from biomedical engineering to oil and gas recovery. Meeting the specific requirements and criteria of these diverse fields necessitates the development of colloidal gels with highly tunable properties to optimize their performance for a wide range of applications. Hence, both scientific and industrial advancement call for more control over the gel properties by exploring novel practical parameters. This dissertation describes an …

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Chemical And Physical Interaction Mechanisms And Multifunctional Properties Of Plant Based Graphene In Carbon Fiber Epoxy Composites, Daniel W. Mulqueen Aug 2023

Chemical And Physical Interaction Mechanisms And Multifunctional Properties Of Plant Based Graphene In Carbon Fiber Epoxy Composites, Daniel W. Mulqueen

Mechanical & Aerospace Engineering Theses & Dissertations

Graphene has generated substantial interest as a filler due to its exceptional strength, flexibility, and conductivity but faces obstacles in supply and implementation. A renewable, plant-based graphene nanoparticle (pGNP) presents a more accessible and sustainable filler with the same properties as mineral graphenes. In this study, the mechanisms of graphene reinforcement in carbon fiber reinforced plastic (CFRP) were examined, along with the resulting improvements to mechanical strength, resistance to crack propagation, electrical and thermal conductivity at elevated temperatures. pGNP, produced from renewable biomass, was shown to have a graphitic structure with flakes 3-10 layers thick and a median lateral size …

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Faceted Nanomaterial Synthesis, Characterizations And Applications In Reactive Electrochemical Membrane Filtration, Qingquan Ma Dec 2022

Faceted Nanomaterial Synthesis, Characterizations And Applications In Reactive Electrochemical Membrane Filtration, Qingquan Ma

Dissertations

Facet engineering of nanomaterials, especially metals and metal oxides has become an important strategy for tuning catalytic properties and functions from heterogeneous catalysis to electrochemical catalysis, photocatalysis, biomedicine, fuel cells, and gas sensors. The catalytic properties are highly related to the surface electronic structures, surface electron transport characteristics, and active center structures of catalysts, which can be tailored by surface facet control. The aim of this doctoral dissertation research is to study the facet-dependent properties of metal or metal oxide nanoparticles using multiple advanced characterization techniques. Specifically, the novel atomic force microscope-scanning electrochemical microscope (AFM-SECM) and density functional theory (DFT) …

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Electromechanical Effects On Micro And Nano Particles Generated From Drug Delivery Devices And Their Implications In Flow And Deposition Efficiency, Mohammed Ali, Mark Miller Nov 2022

Electromechanical Effects On Micro And Nano Particles Generated From Drug Delivery Devices And Their Implications In Flow And Deposition Efficiency, Mohammed Ali, Mark Miller

Technology Faculty Publications and Presentations

This experimental investigation was undertaken to quantify the electrostatic charge and aerodynamic size distribution of the medicinal drug particles inhaled through an in-vitro mouth-throat (MT) in order to compare the amount of drugs can be delivered to the human lung while mimicking a patient is either sitting or lying. The MT model is a cadaver-based replica cast of human oral-pharyngeal-laryngeal region. Tested drug aerosols were generated by a commercially available metered dose inhaler (MDI). The MT model was placed inside a humidity (95%) and temperature (37oC) controlled chamber. Its mouth-inlet was positioned horizontally and vertically to simulate sitting …

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Optimization Of A Novel Barnes Maze Protocol For Assessing Antioxidant Treatment Of Traumatic Brain Injury, Connor C. Gee Jul 2022

Optimization Of A Novel Barnes Maze Protocol For Assessing Antioxidant Treatment Of Traumatic Brain Injury, Connor C. Gee

Department of Biological Systems Engineering: Dissertations and Theses

Current preclinical research into traumatic brain injury focuses heavily upon cellular and molecular testing to determine the effects of injury and potential benefits of neuroprotective treatments. While this may be a useful method, some argue that an increased focus on behavioral testing could lead to better clinical translation as these assays assess the longer term, downstream effects from a brain injury. The most characterized behavioral tests used in traumatic brain injury research are the spatial learning and memory paradigms, Morris Water Maze and Barnes Maze. The Morris Water Maze is the most used of theses paradigms and relies on spatial …

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Interactions Between Soft Nanoparticles And Mammalian Cells, Mitchell Raith May 2022

Interactions Between Soft Nanoparticles And Mammalian Cells, Mitchell Raith

Doctoral Dissertations

Nanoparticles have been of interest to the pharmaceutical industry since the 1980s. The first FDA approved nanoparticle-based therapies included liposomal anesthesia agents. Since then, the amount of FDA-approved nanoparticle therapies remains low. This is because nanoparticle-patient interactions can be very complex and are not well understood. Complicating factors also include increasing obesity rates among the patient population and many small animal pre-clinical trials are completed with healthy, lean animals. The biochemical differences between lean and obese patients prevents early studies from accurately predicting nanoparticle clinical behaviors. Many nanoparticles fail in trails. In this thesis, I aimed to uncover how nanoparticles …

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A Molecular Dynamics Study Of The Laser Sintering Process And Subsequent Mechanical Properties Of Γ-Tial Nanoparticles, Eleanor Dickens Apr 2022

A Molecular Dynamics Study Of The Laser Sintering Process And Subsequent Mechanical Properties Of Γ-Tial Nanoparticles, Eleanor Dickens

Honors Theses

Using molecular dynamics (MD) simulations, the laser sintering additive manufacturing process is investigated through the observation of γ-TiAl nanoparticles. This process is conducted using both uni-directional chain and stacking configurations. By mimicking the heating process and varying laser sintering parameters such as heating rater, sintering temperature, and particle orientation, the fusion behavior and resulting products are analyzed for both chain and stacking NP patterns. In of single chain cases, it is noticed that slower heating rates and higher melting temperatures yield larger neck growth between each individual particle and thus produce a more stable product. This leads to stronger mechanical …

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Limits Of Detection Of Mycotoxins By Laminar Flow Strips: A Review, Xinyi Zhao, Hugh Byrne, Christine M. O’Connor, James Curtin, Furong Tian Apr 2022

Limits Of Detection Of Mycotoxins By Laminar Flow Strips: A Review, Xinyi Zhao, Hugh Byrne, Christine M. O’Connor, James Curtin, Furong Tian

Articles

Mycotoxins are secondary metabolic products of fungi. They are poisonous, carcinogenic, and mutagenic in nature and pose a serious health threat to both humans and animals, causing severe illnesses and even death. Rapid, simple and low-cost methods of detection of mycotoxins are of immense importance and in great demand in the food and beverage industry, as well as in agriculture and environmental monitoring, and, for this purpose, lateral flow immunochromatographic strips (ICSTs) have been widely used in food safety and environmental monitoring. The literature to date describing the development of ICSTs for the detection of different types of mycotoxins using …

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Strategy For Conjugating Oligopeptides To Mesoporous Silica Nanoparticles Using Diazirine-Based Heterobifunctional Linkers, Md Arif Khan, Ramy W. Ghanim, Maelyn R. Kiser, Mahsa Moradipour, Dennis T. Rogers, John M. Littleton, Luke H. Bradley, Bert C. Lynn, Stephen E. Rankin, Barbara L. Knutson Feb 2022

Strategy For Conjugating Oligopeptides To Mesoporous Silica Nanoparticles Using Diazirine-Based Heterobifunctional Linkers, Md Arif Khan, Ramy W. Ghanim, Maelyn R. Kiser, Mahsa Moradipour, Dennis T. Rogers, John M. Littleton, Luke H. Bradley, Bert C. Lynn, Stephen E. Rankin, Barbara L. Knutson

Chemical and Materials Engineering Faculty Publications

Successful strategies for the attachment of oligopeptides to mesoporous silica with pores large enough to load biomolecules should utilize the high surface area of pores to provide an accessible, protective environment. A two-step oligopeptide functionalization strategy is examined here using diazirine-based heterobifunctional linkers. Mesoporous silica nanoparticles (MSNPs) with average pore diameter of ~8 nm and surface area of ~730 m2/g were synthesized and amine-functionalized. Tetrapeptides Gly-Gly-Gly-Gly (GGGG) and Arg-Ser-Ser-Val (RSSV), and a peptide comprised of four copies of RSSV (4RSSV), were covalently attached via their N-terminus to the amine groups on the particle surface by a heterobifunctional linker, …

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Characterization Of Nanoparticles Using Inductively-Coupled Plasma Mass Spectrometry, Jabez D. Campbell Jan 2022

Characterization Of Nanoparticles Using Inductively-Coupled Plasma Mass Spectrometry, Jabez D. Campbell

MSU Graduate Theses

Nanomaterials are a relatively new class of materials that have many applications which span a wide host of fields from medical products to consumer products. The possible compositions and forms of nanomaterials are just as varied as the applications. Therefore, a versatile characterization method is needed for researchers and regulators alike to ensure nanomaterials are properly used. Single Particle Inductively Coupled Plasma Mass Spectrometry (SP-ICP-MS) is a functional method that could fill the characterization need in the nanomaterial research field. Using data from both SP-ICP-MS tests and data from literature established characterization methods, the viability of making SP-ICP-MS the standard …

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Study On Forming Dna-Mediated Nanoparticle Conjugates: Toward Detection Of Covid-19, Chinmay Nitin Afzulpurkar Dec 2021

Study On Forming Dna-Mediated Nanoparticle Conjugates: Toward Detection Of Covid-19, Chinmay Nitin Afzulpurkar

Material Science and Engineering Theses

The objective of this thesis is to establish a rapid, robust, and reproducible procedure to controllably assemble DNA-functionalized Au nanoparticles (AuNPs) into satellite-shaped nanostructures using sequence-specific DNA hybridization. A target DNA strand with COVID-19 sequence (t-DNA) is used as a bridge to connect a capture DNA functionalized on a 50nm gold nanoparticle (C-AuNP) and a probe DNA functionalized on a 30nm nanoparticle (P-AuNP), creating C-AuNP/t-DNA/P-AuNP conjugates. The C-DNA is complementary to a portion of t-DNA, and P-DNA is complementary to the other portion of t-DNA. The parameters that affect the conjugate formation, including hybridization buffer strength, hybridization temperature, and DNA …

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Investigation Of Control Parameters, Strategies, And Transport Modeling For Effective Electrokinetic Nanoparticle Treatment Of Cementitious Materials, Huayuan Zhong Nov 2021

Investigation Of Control Parameters, Strategies, And Transport Modeling For Effective Electrokinetic Nanoparticle Treatment Of Cementitious Materials, Huayuan Zhong

Doctoral Dissertations

Various deleterious chemical species (including sulfates, chlorides, and others) contaminate concrete structures which are inherently porous and thus suffer from compromised durability. Several technologies have been developed for repairing concrete or enhancing the service life. Nevertheless, their efficiency, practicability, and cost can vary widely. Compared with chemical grout, fiber wrap, and traditional repair technology, electrokinetic nanoparticle treatment (EN) has been found to provide remarkable benefits for strength restoration and mitigation of durability problems via porosity reduction. Nanoparticle instability and over dosage issues can arise and lead to problems during treatments. In many cases, these treatment processes have been accompanied by …

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Poly(Lactic-Co-Glycolic Acid) Nanoparticle Delivery Of Notch Intracellular Domain Plasmid To Restore Notch Signaling, Victoria L. Messerschmidt Aug 2021

Poly(Lactic-Co-Glycolic Acid) Nanoparticle Delivery Of Notch Intracellular Domain Plasmid To Restore Notch Signaling, Victoria L. Messerschmidt

Bioengineering Dissertations

Notch signaling is a highly conserved signaling system that is required for embryonic development and regeneration of organs. When the signal is lost, maldevelopment occurs and leads to a lethal state. Delivering exogenous genetic materials encoding Notch into cells can reestablish downstream signaling and rescue cellular functions. Here, we utilized the negatively charged and FDA approved polymer poly(lactic-co-glycolic acid) to encapsulate Notch Intracellular Domain-containing plasmid in nanoparticles. We show that primary human umbilical vein endothelial cells (HUVECs) readily uptake the nanoparticles with and without specific antibody targets. We demonstrated in vitro that our nanoparticles are nontoxic, stable over time, and …

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A Systematic Multiscale Investigation Of Nanoparticle-Assisted Co2 Enhanced Oil Recovery (Eor) Process For Shale Oil Reservoirs, Dayo A. Afekare Mar 2021

A Systematic Multiscale Investigation Of Nanoparticle-Assisted Co2 Enhanced Oil Recovery (Eor) Process For Shale Oil Reservoirs, Dayo A. Afekare

LSU Doctoral Dissertations

Shale oil reservoirs are prolific on the short term due to hydraulic fracturing and horizontal drilling but experience significant production decline, leading to poor ultimate recovery and leaving billions of barrels of oil buried in the ground. In this study, a systematic multi-scale investigation of an enhanced oil recovery (EOR) process using relatively inexpensive silicon dioxide nanoparticles and carbon dioxide for shale oil reservoirs was conducted. Using the Tuscaloosa Marine Shale (TMS) as a case study, aqueous dispersions of nanosilica in conjunction with CO2 were investigated at nano-to-core scales. At the nanoscale, atomic force microscope was used to investigate …

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Investigating The Antitumor Effects Of A Dsrna-Nanoparticle Complex In An In Vitro Ovarian Cancer Model, Aaron Lewis Jan 2021

Investigating The Antitumor Effects Of A Dsrna-Nanoparticle Complex In An In Vitro Ovarian Cancer Model, Aaron Lewis

Theses and Dissertations (Comprehensive)

An estimated 1 in 70 women will be diagnosed with ovarian cancer in their lifetime. Despite advanced detection and treatment methods, it remains a silent killer with an expected survival rate of 50%. A developing method in cancer treatment is the use of compounds that stimulate the immune system to aid in the body's fight against the disease. This project focused on the use of the potent immune stimulant double-stranded RNA (dsRNA), commercially available as polyinosinic:polycytidylic acid, poly(I:C), to induce cytotoxicity in two ovarian cancer cell lines; SKOV-3 and OVCAR-3. Some challenges exist with the delivery of dsRNA due to …

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Exploring A Platinum Nanocatalytic Microcombustion-Thermoelectric Coupled Device, Dylan Moore Mcnally Dec 2020

Exploring A Platinum Nanocatalytic Microcombustion-Thermoelectric Coupled Device, Dylan Moore Mcnally

Theses and Dissertations

This work aimed to create a first-generation power device for eventual application to portable electronics. A platinum nanoparticle catalytic substrate was employed in a microcombustion-thermoelectric coupled (MTC) device for the purpose of chemical-to-electrical energy conversion. Multiple microcombustion reactors were designed, fabricated, and investigated. Most importantly, the reactor configuration was designed to accommodate thermoelectric generators (TEGs) for power production. Temperature studies with catalytic combustion of methanol-air fuel mixtures were used to evaluate the thermal power generation performance of each reactor. The final reactor design enabled ignition at room temperature with the ability to achieve repeat catalytic cycles upon subsequent exposure to …

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Polymeric Nanoparticles As An Antioxidant Delivery System For Age-Related Eye Disease, Sean M. Swetledge Jul 2020

Polymeric Nanoparticles As An Antioxidant Delivery System For Age-Related Eye Disease, Sean M. Swetledge

LSU Doctoral Dissertations

Advantages of polymeric nanoparticles as ocular drug delivery systems include controlled release, enhanced drug stability and bioavailability, and specific tissue targeting. Nanoparticle properties such as hydrophobicity, size, and charge, mucoadhesion, as well as administration route and suspension media affect their ability to overcome ocular barriers and distribute in the eye, and must be carefully designed for specific target tissues and ocular diseases. A review was conducted to serve as a guide to optimizing polymeric nanoparticle delivery systems for ocular drug delivery by discussing the effects of nanoparticle composition and administration method on their ocular penetration, distribution, elimination, toxicity, and efficacy, …

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Research Of Properties Of Composite Elastomeric Material Filled With Montmorillonite Of Karakalpakstan With Nanoparticles, Bakhadir Bakhramovich Kakharov, Akhmadjan Ibadullaev, Elmira Ubaydullayevna Teshabaeva, Marziya Begdullayevna Muftullayeva May 2020

Research Of Properties Of Composite Elastomeric Material Filled With Montmorillonite Of Karakalpakstan With Nanoparticles, Bakhadir Bakhramovich Kakharov, Akhmadjan Ibadullaev, Elmira Ubaydullayevna Teshabaeva, Marziya Begdullayevna Muftullayeva

Journal of Tashkent Institute of Railway Engineers

The paper presents the results of studies on the effect of montmorillonite of Karakalpakstan with nanoparticles on the specific properties of composite elastomeric materials based on a mixture of rubbers SKMS-30 ARKM-15 (70%) and SKN-26 (30%). It was found that with an increase in the filler content in rubber, the recoverability of the rubber compound after deformation is significantly reduced. Moreover, the ability of the system to accumulate the energy of elastic deformation, i.e. the swelling of the extrudate (Re), largely depends on the specific geometric surface (Ssp) of montmorillonite of Karakalpakstan. Studies of the properties of rubbers showed that …

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Resistive Switching Characteristics Of Nanostructured And Solution-Processed Complex Oxide Assemblies, Zimu Zhou May 2020

Resistive Switching Characteristics Of Nanostructured And Solution-Processed Complex Oxide Assemblies, Zimu Zhou

Doctoral Dissertations

Miniaturization of conventional nonvolatile (NVM) memory devices is rapidly approaching the physical limitations of the constituent materials. An emerging random access memory (RAM), nanoscale resistive RAM (RRAM), has the potential to replace conventional nonvolatile memory and could foster novel type of computing due to its fast switching speed, high scalability, and low power consumption. RRAM, or memristors, represent a class of two terminal devices comprising an insulating layer, such as a metal oxide, sandwiched between two terminal electrodes that exhibits two or more distinct resistance states that depend on the history of the applied bias. While the sudden resistance reduction …

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A Micro-Nano Particle System For Sustained Drug Release In Lung Cancer Therapy, Heta N. Jadhav Mar 2020

A Micro-Nano Particle System For Sustained Drug Release In Lung Cancer Therapy, Heta N. Jadhav

USF Tampa Graduate Theses and Dissertations

Lung cancer remains the leading cause of cancer-related mortality in men and women worldwide (National Comprehensive Cancer Network). Hence, developing an effective new therapy to treat lung cancer is under intense investigation. Specifically, the sustained release of a drug in lung tumors is critically important. Previous studies at the USF have shown that telmisartan exhibits synergistic properties when combined with Actinomycin-D for lung cancer treatment. The objective of this study is to develop a novel micro/nano system consisting of lipids and chitosan polymers that would be able to deliver Tel directly to the lungs and release its payloads in a …

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Preparation Of Intra-Articular Drug Delivery Systems For The Treatment Of Osteoarthritis, Ian Villamagna Jan 2020

Preparation Of Intra-Articular Drug Delivery Systems For The Treatment Of Osteoarthritis, Ian Villamagna

Electronic Thesis and Dissertation Repository

Osteoarthritis (OA) is a degenerative disease of the articular joints that affects over 240 million people globally. Despite its overwhelming prevalence, there is no disease modifying agent currently available to treat the disease, and many treatment options remain palliative in nature. Potentially effective treatments for OA are limited by probable systemic side effects. Intra-articular drug delivery systems present a new opportunity for the treatment of OA; encapsulated therapeutics can be injected directly into the joint, at the area of injury, thereby bypassing systemic administration and diminishing the chance for side effects. This thesis describes the research and development of novel …

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Towards Machine Learning In Chemical Sensing : Milk Differentiation And Quality Control Through Two-Dimensional Nano-Sensor Array, Yu Sheng Chen Jan 2020

Towards Machine Learning In Chemical Sensing : Milk Differentiation And Quality Control Through Two-Dimensional Nano-Sensor Array, Yu Sheng Chen

Legacy Theses & Dissertations (2009 - 2024)

Herein, we developed a novel artificial tongue using machine learning and 12 nanoassemblies (2D-NAs) to identify and analyzed different kinds of milk beverages for quality control. This biomimetic sensor array was trained to “taste” different milk types as an “artificial tongue” which is the first time we demonstrated that this sensor array can be implemented to complex systems. Two-dimensional nanoparticles (2D-nps) and nine fluorescently labeled single stranded oligonucleotides (ssDNA) with different length and nucleobases were assembled to create 12 2D-NAs. The artificial tongue was deployed to identify and analyze five milk types. All five milk types were discriminated with 95% …

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Factors Impacting The Transport And Enhanced Oil Recovery Potential Of Polymeric Nanogel In Sandstone, Haifeng Ding Jan 2020

Factors Impacting The Transport And Enhanced Oil Recovery Potential Of Polymeric Nanogel In Sandstone, Haifeng Ding

Doctoral Dissertations

"Enhanced oil recovery (EOR) using nanometer-sized particles has drawn great attention in the oil industry because of their various advantages brought by size. However, their applications on a field scale are very limited, especially for deformable nanoparticles. The objective of this research is to explore the transport behavior of deformable polymeric nanoparticles (nanogel), the factors impacting these behavior, and their EOR potentials. First, 240 published nanoparticle core flooding experiment data were collected and analyzed about the extent to what the nanoparticles can improve oil recovery. Results show that on the laboratory scale the incremental oil recovery could be as high …

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Life Cycle Studies To Evaluate The Physiological And Biochemical Effects Of Copper Oxide And Surface-Coated Titanium Dioxide Nanoparticles On Green Onion (Allium Fistulosum) And Carrot (Daucus Carota L.) Plants: Insights Utilizing Two-Photon Microscopy And Spectroscopy, Yi Wang Jan 2020

Life Cycle Studies To Evaluate The Physiological And Biochemical Effects Of Copper Oxide And Surface-Coated Titanium Dioxide Nanoparticles On Green Onion (Allium Fistulosum) And Carrot (Daucus Carota L.) Plants: Insights Utilizing Two-Photon Microscopy And Spectroscopy, Yi Wang

Open Access Theses & Dissertations

With the recent increase of nanomaterial production, nano copper oxide (nCuO) and surface-modified titanium dioxide nanoparticles (nTiO2) are among the most widely applied nanoparticles in industry and daily lives. Their use has resulted in accumulation in soils as a consequence of their direct or indirect release. Hence, these NPs may raise a potential risk to crops cultivated in soils. Moreover, the physiological effects of nCuO on green onion (Allium fistulosum) and surface-coated nTiO2 on full-grown carrot (Daucus carota L.) are still unknown. Green onion is characterized by its high content of the antioxidant allicin, and carrot is a worldwide economic …

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Stabilization Of Bimodal Colloidal Systems Via Nanoparticle Haloing In Microgravity., Luke Hawtrey Dec 2019

Stabilization Of Bimodal Colloidal Systems Via Nanoparticle Haloing In Microgravity., Luke Hawtrey

Electronic Theses and Dissertations

Colloidal suspensions typically contain a multi-phase system of solid particles suspended in a liquid medium. Colloids are widely used in industrial applications such as inks, paints, motor oils, foods, cosmetics, and many more. Colloidal systems are typically formed by the interaction of the attractive van der Waals forces and one or more repulsive forces. These repulsive forces include electrostatic repulsion, steric hindrance, and nanoparticle haloing. Nanoparticle Haloing (NPH) is a phenomenon discovered in 2001 as a viable method to stabilize colloidal systems of uncharged silica microparticles using highly charged zirconia nanoparticles. For this thesis the effects of NPH were tested …

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Organically Modified Inorganic Nanoparticles For Halochromic Ionophores And Nucleic Acids, William Johnston Aug 2019

Organically Modified Inorganic Nanoparticles For Halochromic Ionophores And Nucleic Acids, William Johnston

Doctoral Dissertations

In this dissertation, four nanoparticle reaction schemes were developed as substrates for halochromic dyes or nucleic acids. The reaction schemes include the use of two substrates: silica nanoparticles and halloysite nanotubes. The protocols can incorporate silica (SiO2) nanoparticles and halloysite aluminosilicate (AlO2SiO2) nanotubes due to the presence of silane groups on the surface of either substrate. The reaction schemes are presented along with detailed protocols which were written to facilitate both reproducibility and to serve as an aid to further study and for easy modification of the protocol to suit a researcher's needs. The data is discussed in the materials …

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Rheological Investigations Of Self-Assembled Block Copolymer Nanocomposites With Complex Architectures, Benjamin Yavitt Jul 2019

Rheological Investigations Of Self-Assembled Block Copolymer Nanocomposites With Complex Architectures, Benjamin Yavitt

Doctoral Dissertations

The self-assembly of block copolymers (BCP) into microphase separated structures is an attractive route to template and assemble functional nanoparticles (NP) into highly ordered nanocomposites and is central to the “bottom up” fabrication of future materials with tunable electronic, optical, magnetic, and mechanical properties. The optimization of the co-assembly requires an understanding of the fundamentals of phase behavior, intermolecular interactions and dynamics of the polymeric structure. Rheology is a novel characterization tool to investigate these processes in such systems that are not accessible by other means. With the combination of X-ray scattering techniques, structure-property relationships are determined as a function …

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Stabilizing Action Of Sodium Citrate When Receiving Silver Nanoparticles By The Method Of Chemical Restoration, Komil M. Mukimov, Shamil M. Sharipov, Tal’At S. Asilov, Asliddin Kh. Bakhriddinov Apr 2019

Stabilizing Action Of Sodium Citrate When Receiving Silver Nanoparticles By The Method Of Chemical Restoration, Komil M. Mukimov, Shamil M. Sharipov, Tal’At S. Asilov, Asliddin Kh. Bakhriddinov

Euroasian Journal of Semiconductors Science and Engineering

The results of the synthesis of colloidal silver nanoparticles by the method of chemical reduction by ascorbic acid in the presence of sodium citrate are presented. The use of ascorbic acid as a reducing agent allows the synthesis of nanoparticles at room temperature. This makes it possible to study the mechanisms of the stabilizing effect of sodium citrate in the process of obtaining nanoparticles.

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