Nanoscience and Nanotechnology Commons^™

Investigation Of Spontaneously Patterned Nanoporous Organosilicate Thin Film Channels For Liquid Chromatography Applications., Ashwin Sanjay Bhaskaran

Graduate Research Theses & Dissertations

Microscale devices are attractive options for the advancement of biomedical engineering and life science. They have huge potential in the pharmaceutical and biomedical fields provided the critical factors such as device size, product purity and efficiency are not a hindrance. In most cases, traditional microelectronics fabrication processes are quite costly and complicated. By improving on them, their application in fields such as chemical sensing, detection and analysis is possible. By implementing this on a chip, we can reduce the cost and improve portability. This thesis focuses on the investigation of a novel class of spontaneously patterned nanoporous organosilicate nanoparticle-based films …

Development Of Novel Polymeric Materials For Their Application In Monitoring And Remediation Of Environmental Pollutants, Rishabh Shah

Theses and Dissertations--Chemical and Materials Engineering

Remediation of environmental pollutants from water is one of the major challenges in the 21st century. Utilizing novel polymeric materials to accomplish this challenge has garnered a lot of interest in recent times. Flexibility in synthesizing as well as functionalizing makes them attractive for their application in pollutant remediation. This work is based on development and characterization of novel crosslinked polymeric as well as linear polymeric materials from biphenyl-based monomers, biphenyl based crosslinker and a temperature responsive monomer (Nisopropylacrylamide (NIPAAm)) for their application in remediation of toxic pollutants such as polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs) and iron oxide nanoparticle …

Recent Advances In Preparation And Testing Methods Of Engine-Based Nanolubricants: A State-Of-The-Art Review, Sayed Akl, Sherif Elsoudy, Ahmed A. Abdel-Rehim, Serag Salem, Mark Ellis

Mechanical Engineering

Reducing power losses in engines is considered a key parameter of their efficiency improvement. Nanotechnology, as an interface technology, is considered one of the most promising strategies for this purpose. As a consumable liquid, researchers have studied nanolubricants through the last decade as potential engine oil. Nanolubricants were shown to cause a considerable reduction in the engine frictional and thermal losses, and fuel consumption as well. Despite that, numerous drawbacks regarding the quality of the processed nanolubricants were discerned. This includes the dispersion stability of these fluids and the lack of actual engine experiments. It has been shown that the …

Designing Transition Metal Chalcogenides Electrocatalyst Surfaces For High-Efficiency Water Oxidation, Umanga De Silva

Doctoral Dissertations

”The rising demand for energy security and reducing fossil fuel dependence has prompted researchers to search for a clean, sustainable, and efficient energy generation system with low environmental impact. Water electrolysis has been identified as one of the most important processes satisfying the above needs to generate hydrogen as a clean fuel. Two half-cell reactions of oxygen evolution reaction (OER) at the anode and hydrogen evolution reaction (HER) at the cathode comprise the main process of water electrolysis. However, the oxygen evolution reaction is the most crucial step for efficient water splitting. Traditionally, metal oxides have been utilized as catalysts …

From Bench To Worktop: Rapid Evaluation Of Nutritional Parameters In Liquid Foodstuffs By Ir Spectroscopy, David Perezguaita

Articles

We evaluated the use of attenuated total reflectance infrared spectroscopy for simultaneous in situ quantification of the nutritional composition of liquid food stuffs in the industrial kitchen context. Different methodologies were compared, including dry and wet acquisition along with instrument parameters and measurement times of 4 and 60 s. The most effective technique was 1-minute measurement, with prediction errors of 2.6, 0.7, 1.0, 2.2, 0.8, 2.4 g/100 mL and 150 Kcal, for carbohydrates, proteins, fat, sugars, saturated fat, water and energy values, respectively.The 4-second method resulted in larger errors but was more applicable for inline measurements. Dry measurements successfully predicted …

Tuning The Wettability Of Metal Surface With Electrodeposited Porous Copper And Graphene Coatings, Husam Eltigani

Chulalongkorn University Theses and Dissertations (Chula ETD)

Electrodeposition of porous copper is an interesting type of coating that is emerging for various applications. However, the understanding of the relationships between copper surface wettability control and electrodeposition parameters and post-electrodeposition storage conditions is quite limited. Furthermore, it is worthwhile to explore how nanomaterials such as graphene would interact with porous copper to provide surface wettability modifications. This work therefore aims to develop a framework for the relationship of copper and graphene deposition processes, storage conditions, and the wetting behavior of copper surfaces. The research work performed in this study is divided into 2 parts: (i) effects of plating …

Continuous Preparation And Application Of Novel Heterogeneous Catalysis, Michael B. Burkholder

Theses and Dissertations

Transition metal heterogeneous catalysts are widely used across many chemical industries to reduce waste and emissions and reduce production time while increasing rate. The prevalence of these materials results from the complex relationship between metal nanoparticles and supports affecting final catalytic performance. Rational catalyst synthesis describes the ability to precisely engineer structures through controlled preparation. Novel materials and continuous processing represent a promising approach for rational catalyst synthesis.

The application of these catalysts in continuous, multiphase processes, such as cross-coupling reactions, oxidation chemistry, and nitroreduction processes, are paramount to developing new commercial routes for high-value products. Pd/G catalysts synthesized by …

Nebulizer-Based Systems To Improve Pharmaceutical Aerosol Delivery To The Lungs, Benjamin M. Spence

Theses and Dissertations

Combining vibrating mesh nebulizers with additional new technologies leads to substantial improvements in pharmaceutical aerosol delivery to the lungs across therapeutic administration methods. In this dissertation, streamlined components, aerosol administration synchronization, and/or Excipient Enhanced Growth (EEG) technologies were utilized to develop and test several novel devices and aerosol delivery systems. The first focus of this work was to improve the poor delivery efficiency, e.g., 3.6% of nominal dose (Dugernier et al. 2017), of aerosolized medication administration to adult human subjects concurrent with high flow nasal cannula (HFNC) therapy, a form of continuous-flow non-invasive ventilation (NIV). The developed Low-Volume Mixer-Heater (LVMH) …

In Depth Characterisation Of The Biomolecular Coronas Of Polymer Coated Inorganic Nanoparticles With Differential Centrifugal Sedimentation, André Perez-Potti, Hender Lopez, Beatriz Pelaz, Abuelmagd Abdelmonem, Mahmoud G. Soliman, Ingmar Schoen, Philip M. Kelly, Kenneth A. Dawson, Wolfgang J. Parak, Zeljka Krpetic, Marco P. Monopoli

Articles

Advances in nanofabrication methods have enabled the tailoring of new strategies towards the controlled production of nanoparticles with attractive applications in healthcare. In many cases, their characterisation remains a big challenge, particularly for small-sized functional nanoparticles of 5 nm diameter or smaller, where current particle sizing techniques struggle to provide the required sensitivity and accuracy. There is a clear need for the development of new reliable characterisation approaches for the physico-chemical characterisation of nanoparticles with significant accuracy, particularly for the analysis of the particles in the presence of complex biological fluids. Herein, we show that the Differential Centrifugal Sedimentation can …

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 …

Treated Hfo2 Based Rram Devices With Ru, Tan, Tin As Top Electrode For In-Memory Computing Hardware, Yuvraj Dineshkumar Patel

Theses

The scalability and power efficiency of the conventional CMOS technology is steadily coming to a halt due to increasing problems and challenges in fabrication technology. Many non-volatile memory devices have emerged recently to meet the scaling challenges. Memory devices such as RRAMs or ReRAM (Resistive Random-Access Memory) have proved to be a promising candidate for analog in memory computing applications related to inference and learning in artificial intelligence. A RRAM cell has a MIM (Metal insulator metal) structure that exhibits reversible resistive switching on application of positive or negative voltage. But detailed studies on the power consumption, repeatability and retention …

Preparations And Photoelectrochemical Performances Of Rgo-Tio2 Nanotubes Arrays, Ze-Yang Zhang, Lan Sun, Chang-Jian Lin

Journal of Electrochemistry

Decorating TiO₂ nanotube arrays with RGO to improve the photocatalytic activity of TiO₂ nanotube arrays has been reported. For the reported RGO-TiO₂ nanotube arrays, TiO₂ nanotube arrays were prepared by anodizing the high-purity Ti foil in an organic electrolyte for multiple-step treatments, while RGO were deposited on TiO₂ nanotube arrays by using cyclic voltammetry or other electrical reduction methods. To enhance the reduction degree and the coverage of RGO on the resultant RGO-TiO₂ nanotube arrays, in this work, the one-step electrochemical anodization in hydrofluoric acid was used to fabricate TiO₂ nanotube arrays with …

Novel Electrochemical Sensor Based On Integration Of Nanoporous Gold With Molecularly Imprinted Polymer For Detection Of Arsenic Ion(Iii), Wu-Wei Ma, Qi-Gang Chang, Xiong-Fang Shi, Yan-Bin Tong, Li Zhou, Bang-Ce Ye, Jian-Jiang Lu, Jin-Hu Zhao

Journal of Electrochemistry

Arsenic, a toxic chemical element, is detrimental to environment and human health in particular. Therefore, the development of simple, fast, and accurate arsenic ion (As³⁺) detection methods has attracted extensive attention. In this work, an electrochemical sensor based on molecular imprinted polymer (MIP) and nano-porous gold (NPG) modified indium tin oxide (ITO) electrode (MIP/NPG/ITO) was developed for determination of As³⁺ in water with different quality. NPG with high conductivity, large specific surface area and high biocompatibility was prepared in situ on ITO surface by a green electrodeposition method using simple and controllable steps. Then, a layer of …

Core-Shell Structured Ru@Ptru Nanoflower Electrocatalysts Toward Alkaline Hydrogen Evolution Reaction, Xue-Liang Wang, Yuan-Yuan Cong, Chen-Xi Qiu, Sheng-Jie Wang, Jia-Qi Qin, Yu-Jiang Song

Journal of Electrochemistry

Water electrolysis for hydrogen production is beneficial for solving the problem of energy crisis and environmental issues. It is necessary to study highly active and cost-effective catalysts toward hydrogen evolution reaction (HER) to reduce the consumption of noble metals. Herein, we report the synthesis of core-shell structured Ru@Pt_0.24Ru nanoflowers electrocatalyst by stepwise reduction of Ru and Pt precursors in the mixture of oleylamine and benzyl alcohol at 160 ^oC. The average diameter of the resultant Ru@Pt_0.24Ru was 16.5±4.0 nm with a bulk atomic ratio between Pt and Ru of 0.24:1 and a surface ratio of …

Microparticle Propulsion For In Vivo Navigation, Louis Rogowski

Mechanical Engineering Research Theses and Dissertations

Microscale propulsion impacts a diverse array of fields, with simplistic microrobots allowing for novel innovations in microscale surgery and drug delivery. Propulsion at the microscale is constrained by physics, with time-reversal and geometric symmetries limiting available propulsion mechanisms. However, certain fluid environments and surface coatings allow for the propulsion of microparticles through externally applied magnetic fields. Presented here is a detailed analysis of microparticles propelling using spontaneous symmetry breaking, flagella surface coatings, and multi-modal actuation mechanisms. Spontaneous symmetry breaking in nonlinearly viscoelastic fluids is presented for the first time in literature, with two equal and opposite propulsion states existing along …

Interface Engineering Of Materials For Energy And Biological Applications, Ardalan Chaichi

LSU Doctoral Dissertations

Interface interactions are generally classified into solid-liquid, solid-gas, solid-vacuum, liquid-gas, light-matter and electron-matter categories. Surface morphological studies as well as surface chemical reactions can be studied in various types of complex systems thanks to technological advances in materials characterization methods. By employing interface engineering in different applications, it is possible to control electrical, chemical, mechanical, optical and biological properties of materials. Accordingly, we have applied interface engineering in three different areas of energy materials, biomaterials and surface imaging. As a result, firstly, we have introduced a high intensity light flash-based method on engineered substrates for delamination of reduced graphene oxide …

Probing The Impacts Of Ultra-Low Platinum Loadings On Membrane Degradation Mechanisms, Andre J. Spears

Nanoscience and Microsystems ETDs

Membrane chemical degradation is one of many factors that can impact fuel cell durability. The fuel cell’s performance and lifetime heavily depends on the membrane and its ability to maintain chemical and mechanical integrity. In Nafion^® membranes, hydroxyl radicals are the primary cause of chemical membrane degradation as they attack the membrane’s polymer structure. Radical formation can ensue via peroxide decomposition at the cathode or gases reacting on Pt particles or contaminants like Fe (a fenton's reagent) within the membrane. As radicals attack the membrane’s polymer structure the membrane thins, and fluoride and sulfate ions are released. This consequently …

The Varied Thermal Response Of Magnetic Iron-Oxide Nanoparticles During Induction Heating In Liquid And Solid-Liquid Phase Change Mediums, Joshua Tompkins

Graduate Theses and Dissertations

This study investigates the induction heating response of uncapped iron oxide nanoparticles sonically dispersed as a nanofluid and mechanically distributed in solid phase change materials. The nanoparticles examined have a mean diameter of 14.42 nm and are magnetically heated in an alternating magnetic field at an amplitude of 72.6 kA/m at frequencies of 217, 303, and 397 kHz. Nanoparticle characterization was undertaken through transition electron microscopy, x-ray diffraction, and dynamic light scattering when in suspension. Carrier fluids were characterized through viscosity, heat capacity, and density measurements which were used in the calorimetric calculation of the specific absorption rate (SAR) of …

Applications Of Cathodoluminescence In Plasmonic Nanostructures And Ultrathin Inas Quantum Layers, Qigeng Yan

Graduate Theses and Dissertations

Due to the advanced focusing ability, characterization methods based on the electron-beam excitation have been broadly applied to investigate nanomaterials. Structural or compositional information is commonly acquired using electron microscopes. Moreover, taking advantage of the super spatial resolution of the focused electron beam, optical properties of nanomaterials can be also obtained. Herein, general concepts and processes of the interaction between electrons and materials are studied. Two specific optical nanomaterials, including plasmonic nanostructures and semiconductor quantum layers, are investigated by the cathodoluminescence (CL) measurement.

Surface plasmonic resonance can be generated when high-energy electrons strike the interface between the dielectric medium and …

Development And Characterization Of Metal Contacts For Graded Composition Ingan Solar Cells, Reem E. Alhelais

Graduate Theses and Dissertations

There is an increasing demand for high-power electronic components and optoelectronic devices with low-loss and high efficiency. III-nitride semiconductor materials have demonstrated great potential for high-power, high-frequency, and high-temperature applications because of their remarkable and wide-ranging electronic and physical properties. These material systems, including alloys of AlN, GaN, and InN, are currently being explored for their potential to develop efficient photovoltaic cells. They can potentially achieve higher efficiency because of their very high direct wide band edge, absorption coefficients, and resistance to defects. The compositionally graded Group III-nitride alloy allows access to a large range of energies by varying the …