Nanoscience and Nanotechnology Commons^™

Nano-Engineered Soft Magnets: Potential Application In Water Treatment, Hyperthermia And Molecular (Organic) Magnets, Yohannes Weldemariam Getahun

Open Access Theses & Dissertations

Scrutinizing the remarkable and tunable properties of magnetic materials at a nanoscale size "There's Plenty of Room at the Bottom..." Richard Feynman, this study attempts to find sustainable solutions to some of the deteriorating environmental, health, and energy problems the world is encountering. Due to their simple preparation, surface adaptability, and tunable magnetic and optical properties, magnetic nanoparticles have been extensively investigated in water treatment, cancer therapy, data storage, and more. However, relying on non-reusable and chemical-based treatment agents in water, complex and costly cancer treatment procedures and molecular magnets that operate far below room temperature limited those attempts from …

Manufacturing Of Carbon-Based Hybrid Nanocomposites With Engineered Functionalities Via Laser Ablation Synthesis In Solution (Lasis) Techniques, Erick Leonardo Ribeiro

Doctoral Dissertations

Carbon-based composite materials have long been fabricated and extensively used in our daily lives. In the past decades, with rapid development of nanotechnology, these class of material have gained even more attention owing to their outstanding properties which directly results in their prospects to revolutionize technological development in many fields, ranging from medicine to electronics. Nevertheless, for certain applications, including electrochemical energy storage/conversion devices, the chemically inert nature of these materials creates obstacles and thus requires their coupling with other active species. This thesis explores the use of Laser Ablation Synthesis in Solution (LASiS) in tailoring promising strategies and pathways …

Developments Towards High-Flux Silica Nanosphere Substrates To Support Conforming Self-Assembled Gold Nanoparticle Monolayers For Applications In Size-Selective Filtration, Ryan Baker Vincent

Theses, Dissertations and Capstones

Hydrophobic thiol coated gold nanoparticles have recently been investigated for their ability to self-assemble into robust, ultra-thin, porous membranes at a liquid-vapor interface. Due to the well-ordered, hexagonal close-packed nanoparticle arrays formed during the self-assembly process, these 2-dimensional sheets have very well-defined pore structures and have been shown to span gaps of several microns under ideal conditions. While these self-assembled nanoparticle monolayers have very promising applications in the field of size-selective filtration due to their well-defined pore structure, they need to be supported by a rigid substrate with a large amount of open area. Here, tightly packed arrays of silica …

From Flasks To Applications: Design And Optimization Of Giant Quantum Dots Using Traditional And Automated Synthetic Methods, Christina J. Hanson

Nanoscience and Microsystems ETDs

Semiconducting nanocrystals, also known as quantum dots (QDs), that emit light with near-unity quantum yield and are extremely photostable are attractive options as down-conversion and direct electricity-to-light materials for a variety of applications including solid-state lighting, display technologies, bio-imaging and optical tracking. Standard QDs with a core/thin shell structure display fluorescence intermittency (blinking) and photobleaching when exposed to prolonged room temperature excitation for single dot measurements, as well as significant reabsorption and energy transfer when densely packed into polymers or at high solution concentrations.

We have developed thick shell “giant” QDs (gQDs), ultra-stable photon sources both at the ensemble and …

Preparation Parameters Optimization And Electrocatalytic Properties Of Supported Au Nanoparticles, Rui Yao, Yu-Jiang Song, Huan-Qiao Li, Jia Li, Jian-Guo Liu

Journal of Electrochemistry

Due to interesting size effect, physical and chemical properties, nano-scale gold materials have been commonly used to catalytic reactions. However, the application of gold nanomaterials in the field of electrocatalysis is limited. Herein, we report the synthesis of gold nanparticles supported on carbon through chemical reduction of HAuCl₄ by NaBH₄ under mild conditions in the presence of surfactants as soft templates, carbon black or graphene as a support. We investigated a series of key reaction parameters, including reagent concentration, temperature, the types of carbon supports and surfactants. With the optimum synthetic parameters, we successfully obtained supported 1 ~ …

Size-Dependent Interactions Of Metal Nanoparticles With Fluorophores And Semiconductors, Liyana A. Wajira Ariyadasa

Dissertations

In recent years, nanoscale metallic particles have gained considerable interest due to their potential applications in advanced technology. Despite such interest, synthetic procedures that produce gram-scale, well-defined metallic nanoparticles with controlled size and shape, especially with diameters less than 5 nm remains a challenge. Our work has focused on developing synthetic procedures that produce well-defined platinum and palladium metal nanoparticles in the 1-5 nm size range. Thioether ligands were used as stabilizers and resulted in metal nanoparticles with controlled size. The nanoparticles were characterized using transmission electron microscopy (TEM), x-ray diffraction (XRD), selected area electron diffraction (SAED), x-ray photoelectron spectroscopy …

Automating Tolerance Synthesis: A Framework And Tools, Stephen C.-Y. Lu, Robert G. Wilhelm

Department of Mechanical and Materials Engineering: Faculty Publications

This paper describes CASCADE-T—a new approach to tolerance synthesis that uses a complete representation of the conditional tolerance relations that exist between features of a part under design. Conditional tolerances are automatically determined from functional requirements and shape information. Tolerance primitives based on the virtual boundary requirements approach to tolerance representation are composed to form more complex tolerance relationships. Artificial intelligence techniques, including a constraint network, frame-based system, and dependency tracking are used to support flexible and detailed computation for tolerance analysis and synthesis.