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Full-Text Articles in Nanoscience and Nanotechnology

Carbon-Supported Transition Metal Nanoparticles For Catalytic And Electromagnetic Applications, Kavita Meduri Nov 2018

Carbon-Supported Transition Metal Nanoparticles For Catalytic And Electromagnetic Applications, Kavita Meduri

Dissertations and Theses

Recently, there has been growing interest in using transition metals (TM) for catalytic and electromagnetic applications, due to the ability of TMs to form stable compounds in multiple oxidation states. In this research, the focus has been on the synthesis and characterization of carbon-supported TM nanoparticles (NPs), specifically palladium (Pd) and gold (Au) NPs, for catalytic applications, and transition metal oxides (TMO) NPs, specifically Fe3O4 NPs for electromagnetic applications. Carbon supports have several advantages, such as enabling even distribution of particles, offering large specific surface area with excellent electron conductivity, and relative chemical inertness.

In this dissertation ...


Investigation Of The Acoustic Response Of A Confined Mesoscopic Water Film Utilizing A Combined Atomic Force Microscope And Shear Force Microscope Technique, Monte Allen Kozell Jul 2018

Investigation Of The Acoustic Response Of A Confined Mesoscopic Water Film Utilizing A Combined Atomic Force Microscope And Shear Force Microscope Technique, Monte Allen Kozell

Dissertations and Theses

An atomic force microscopy beam-like cantilever is combined with an electrical tuning fork to form a shear force probe that is capable of generating an acoustic response from the mesoscopic water layer under ambient conditions while simultaneously monitoring force applied in the normal direction and the electrical response of the tuning fork shear force probe. Two shear force probes were designed and fabricated. A gallium ion beam was used to deposit carbon as a probe material. The carbon probe material was characterized using energy dispersive x-ray spectroscopy and scanning transmission electron microscopy. The probes were experimentally validated by demonstrating the ...


Development Of A Liquid Contacting Method For Investigating Photovoltaic Properties Of Pbs Quantum Dot Solids, Vitalii Alekseevich Dereviankin Feb 2018

Development Of A Liquid Contacting Method For Investigating Photovoltaic Properties Of Pbs Quantum Dot Solids, Vitalii Alekseevich Dereviankin

Dissertations and Theses

Photovoltaic (PV) devices based on PbS quantum dot (QD) solids demonstrate high photon-to-electron conversion yields. However, record power conversion efficiencies remain limited mainly due to bulk and interfacial defects in the light absorbing material (QD solids). Interfacial defects can be formed when a semiconductor, such as QD solid, is contacted by another material and may predetermine the semiconductor/metal or semiconductor/metal-oxide junction properties. The objective of the work described in this dissertation was set to explore whether electrochemical contacting using liquid electrolytes can provide sufficient means of contacting the QD solids to investigate their PV performance without introducing the ...


Investigation Into Effects Of Instability And Reactivity Of Hydride-Passivated Silicon Nanoparticles On Interband Photoluminescence, Christine Marie Radlinger May 2017

Investigation Into Effects Of Instability And Reactivity Of Hydride-Passivated Silicon Nanoparticles On Interband Photoluminescence, Christine Marie Radlinger

Dissertations and Theses

While silicon has long been utilized for its electronic properties, its use as an optical material has largely been limited due to the poor efficiency of interband transitions. However, discovery of visible photoluminescence (PL) from nanocrystalline silicon in 1990 triggered many ensuing research efforts to optimize PL from nanocrystalline silicon for optical applications. Currently, use of photoluminescent silicon nanoparticles (Si NPs) is commercially limited by: 1) the instability of the energy and intensity of the PL, and 2) the low quantum yield of interband PL from Si NPs.

Herein, red-emitting, hydrogen-passivated silicon nanoparticles (H-Si NPs) were synthesized by thermally-induced disproportionation ...


Architectures And Algorithms For Intrinsic Computation With Memristive Devices, Jens Bûrger Aug 2016

Architectures And Algorithms For Intrinsic Computation With Memristive Devices, Jens Bûrger

Dissertations and Theses

Neuromorphic engineering is the research field dedicated to the study and design of brain-inspired hardware and software tools. Recent advances in emerging nanoelectronics promote the implementation of synaptic connections based on memristive devices. Their non-volatile modifiable conductance was shown to exhibit the synaptic properties often used in connecting and training neural layers. With their nanoscale size and non-volatile memory property, they promise a next step in designing more area and energy efficient neuromorphic hardware.

My research deals with the challenges of harnessing memristive device properties that go beyond the behaviors utilized for synaptic weight storage. Based on devices that exhibit ...


Expanding The Versatility Of Nano Assembled Capsules As Platform Of Potential High Payload Mri Contrast Agents, Annah Farashishiko Jul 2016

Expanding The Versatility Of Nano Assembled Capsules As Platform Of Potential High Payload Mri Contrast Agents, Annah Farashishiko

Dissertations and Theses

Magnetic resonance imaging (MRI) has become a powerful clinical modality in diagnostic medicine. It is non-invasive and offers high spatial and temporal resolution. The goal of molecular imaging is to reveal the pathophysiology underlying the observed anatomy and diagnose diseases. The detection of pathological biomarkers can lead to early recognition of diseases and improved monitoring for recurrence. Clinically available contrast agents are limited in their discrimination of contrast between tissues and they tend to have very high detection limits. Because biomarkers are very low in concentration there is a need for high payload deposition of contrast agent (CA) and targeted ...


Frequency Multiplication In Silicon Nanowires, Marius Mugurel Ghita Jul 2016

Frequency Multiplication In Silicon Nanowires, Marius Mugurel Ghita

Dissertations and Theses

Frequency multiplication is an effect that arises in electronic components that exhibit a non-linear response to electromagnetic stimuli. Barriers to achieving very high frequency response from electronic devices are the device capacitance and other parasitic effects such as resistances that arise from the device geometry and are in general a function of the size of the device. In general, smaller device geometries and features lead to a faster response to electromagnetic stimuli. It was posited that the small size of the silicon nanowires (SiNWs) would lead to small device capacitance and spreading resistance, thus making the silicon nanowires useful in ...


Complete Design Methodology Of A Massively Parallel And Pipelined Memristive Stateful Imply Logic Based Reconfigurable Architecture, Kamela Choudhury Rahman Jun 2016

Complete Design Methodology Of A Massively Parallel And Pipelined Memristive Stateful Imply Logic Based Reconfigurable Architecture, Kamela Choudhury Rahman

Dissertations and Theses

Continued dimensional scaling of CMOS processes is approaching fundamental limits and therefore, alternate new devices and microarchitectures are explored to address the growing need of area scaling and performance gain. New nanotechnologies, such as memristors, emerge. Memristors can be used to perform stateful logic with nanowire crossbars, which allows for implementation of very large binary networks that can be easily reconfigured. This research involves the design of a memristor-based massively parallel datapath for various applications, specifically SIMD (Single Instruction Multiple Data) like architecture, and parallel pipelines. The dissertation develops a new model of massively parallel memristor-CMOS hybrid datapath architectures at ...


One-Dimensional Nanostructure And Sensing Applications: Tin Dioxide Nanowires And Carbon Nanotubes, Hoang Anh Tran Feb 2016

One-Dimensional Nanostructure And Sensing Applications: Tin Dioxide Nanowires And Carbon Nanotubes, Hoang Anh Tran

Dissertations and Theses

The key challenge for a nanomaterial based sensor is how to synthesize in bulk quantity and fabricate an actual device with insightful understanding of operational mechanisms during performance. I report here effective, controllable methods that exploit the concepts of the "green approach" to synthesize two different one-dimensional nanostructures, including tin oxide nanowires and carbon nanotubes. The syntheses are followed by product characterization and sensing device fabrications as well as sensor performance understanding at the molecular level. Sensor-analyte response and recovery kinetics are also presented.

The first part of the thesis describes bulk-scale synthesis and characterization of tin oxide nanowires by ...


Photoluminescent Silicon Nanoparticles: Fluorescent Cellular Imaging Applications And Photoluminescence (Pl) Behavior Study, Sheng-Kuei Chiu Aug 2015

Photoluminescent Silicon Nanoparticles: Fluorescent Cellular Imaging Applications And Photoluminescence (Pl) Behavior Study, Sheng-Kuei Chiu

Dissertations and Theses

Molecular fluorophores and semiconductor quantum dots (QDs) have been used as cellular imaging agents for biomedical research, but each class has challenges associated with their use, including poor photostability or toxicity. Silicon is a semiconductor material that is inexpensive and relatively environmental benign in comparison to heavy metal-containing quantum dots. Thus, red-emitting silicon nanoparticles (Si NPs) are desirable to prepare for cellular imaging application to be used in place of more toxic QDs. However, Si NPs currently suffer poorly understood photoinstability, and furthermore, the origin of the PL remains under debate.

This dissertation first describes the use of diatomaceous earth ...


Optical Properties Of Nanostructured Dielectric Coatings, Brandon Giatti Aug 2014

Optical Properties Of Nanostructured Dielectric Coatings, Brandon Giatti

Dissertations and Theses

Solar cells have extrinsic losses from a variety of sources which can be minimized by optimization of the design and fabrication processes. Reflection from the front surface is one such loss mechanism and has been managed in the past with the usage of planar antireflection coatings. While effective, these coatings are each limited to a single wavelength of light and do not account for varying incident angles of the incoming light source. Three-dimensional nanostructures have shown the ability to inhibit reflection for differing wavelengths and angles of incidence. Nanocones were modeled and show a broadband, multi-angled reflectance decrease due to ...


Project Nano: Will Allowing High School Students To Use Research Grade Scanning Electron Microscopes Increase Their Interest In Science?, Leslie Teneyck Smith Jan 2014

Project Nano: Will Allowing High School Students To Use Research Grade Scanning Electron Microscopes Increase Their Interest In Science?, Leslie Teneyck Smith

Dissertations and Theses

In this study, one AP Biology curriculum unit and one general Biology curriculum unit that included tabletop Scanning Electron Microscope (SEM) technology provided by Project NANO, a grant-funded, collaborative initiative designed to integrate cutting-edge nanotechnology into high school classrooms were implemented at a public high school in rural Oregon. Nine students participated in the AP unit and 52 students participated in the general Biology unit. Each student completed an opinion-based pre and post survey to determine if using the SEM as a part of the curriculum unit had an impact on his or her interest in science or in nanoscience ...


Negotiating The Inclusion Of Nanoscience Content And Technology In Science Curriculum: An Examination Of Secondary Teachers' Thinking In A Professional Development Project, Jennifer Gayle Wells Oct 2013

Negotiating The Inclusion Of Nanoscience Content And Technology In Science Curriculum: An Examination Of Secondary Teachers' Thinking In A Professional Development Project, Jennifer Gayle Wells

Dissertations and Theses

The Next Generation Science Standards represent a significant challenge for K-12 school reform in the United States in the science, technology, engineering and mathematics (STEM) disciplines (NSTA, 2012). One important difference between the National Science Education Standards (NRC, 1996) and the Next Generation Science Standards (Achieve, 2013) is the more extensive inclusion of nanoscale science and technology. Teacher PD is a key vehicle for implementing this STEM education reform effort (NRC, 2012; Smith, 2001).

The context of this dissertation study is Project Nanoscience and Nanotechnology Outreach (NANO), a secondary level professional development program for teachers that provides a summer workshop ...