Nanoscience and Nanotechnology Commons^™

Control Of Phase Of Iron Oxide, Nathan D. Jansen

Center for Electron Microscopy and Nanofabrication Publications and Presentations

Presentation delivered August 10, 2018, at the Research Experiences for Undergraduates Symposium (REU), which focuses on the synthesis of iron oxides for use in nanofabrication. Discusses phases of iron oxide, synthesis methods and experimental uses.

Investigation Of Itx Derivative Photoinitiators For Depletion Lithography, Ran Le, Paul Somers, Liang Pan, Xianfan Xu, Teng Chi, Bryan Boudouris

The Summer Undergraduate Research Fellowship (SURF) Symposium

Direct laser writing (DLW) with two-photon polymerization (TPP) allows for fabricating 3-dimensional nano-scale polymer structures by focusing an ultrafast laser inside a photoresist system consisting of a monomer and photoinitiator. The photoinitiator is excited by the laser and triggers the polymerization process of the monomer. Stimulated emission depletion (STED), which was designed for resolution enhancement for microscopy, could be applied to this process and inhibit the polymerization with an additional laser for depletion. This STED process can be used to increase the resolution of the 3D printing. However, the photoresist for STED-DLW should contain a photoinitiator that is sensitive to …

Thin Film Cocaine Sensors, Datta Sheregar, Vick Hung, Jenna Walker, Orlando Hoilett, Jacqueline Linnes, Robert Nawrocki

The Summer Undergraduate Research Fellowship (SURF) Symposium

Over 7 million Americans suffer from a drug use disorder and up to 60% of individuals treated for addiction will ultimately relapse. We are developing ultra-thin film electrodes on a wearable substrate for a sensor that can detect minute amounts of cocaine in sweat droplets secreted from the skin. This will enable wearable drug monitoring for personalized rehabilitation treatment plans and improve long-term addiction recovery rates. The current research focuses on developing a thin-film sensor that can be applied directly to the skin. First a layer of PVP (poly4-vinylphenol) was prepared and then spun coated onto a piece of glass. …

Predicting And Optimizing Solar Cell Performance With Material/Surface Characteristics, Yiheng Zhu, Allison Perna, Peter Bermel

The Summer Undergraduate Research Fellowship (SURF) Symposium

Renewable energy sources have begun replacing fossil fuels at the utility scale. In particular, photovoltaics has grown rapidly in recent years. To further improve solar technology in terms of cost and efficiency and promote adoption, researchers often seek material and device level advancements. Photovoltaic simulation tools can be utilized to predict device performance before fabrication and experimentation, streamline research processes, and interpret experimental results. Therefore, we developed ContourPV, which simulates various combinations of values of different device characteristics to optimize and predict photovoltaic performance. ContourPV sweeps the inputted range of values for each chosen device or layer characteristic and obtains …

Spice Based Compact Model For Electrical Switching Of Antiferromagnet, Xe Jin Chan, Jan Kaiser, Pramey Upadhyaya

The Summer Undergraduate Research Fellowship (SURF) Symposium

A simulation framework that can model the behavior of antiferromagnets (AFMs) is essential to building novel high-speed devices. The electrical switching of AFMs allows for high performance memory applications. With new phenomena in spintronics being discovered, there is a need for flexible and expandable models. With that in mind, we developed a model for AFMs which can be used to simulate AFM switching behavior in SPICE. This approach can be modified for adding modules, keeping pace with new developments. The proposed AFM switching model is based on the Landau-Lifshitz-Gilbert equation (LLG). LLG along with an exchange coupling module is implemented …

Opto-Thermal Characterization Of Plasmon And Coupled Lattice Resonances In 2-D Metamaterial Arrays, Vinith Bejugam

Graduate Theses and Dissertations

Growing population and climate change inevitably requires longstanding dependency on sustainable sources of energy that are conducive to ecological balance, economies of scale and reduction of waste heat. Plasmonic-photonic systems are at the forefront of offering a promising path towards efficient light harvesting for enhanced optoelectronics, sensing, and chemical separations. Two-dimensional (2-D) metamaterial arrays of plasmonic nanoparticles arranged in polymer lattices developed herein support thermoplasmonic heating at off-resonances (near infrared, NIR) in addition to regular plasmonic resonances (visible), which extends their applicability compared to random dispersions. Especially, thermal responses of 2-D arrays at coupled lattice resonance (CLR) wavelengths were comparable …

Investigations On Hydrothermally Synthesized Co3o4/Mnxco3-Xo4 Core-Shell Nanoparticles, Ning Bian

Graduate Theses/Dissertations

Two different morphologies (pseudo-spherical shaped or PS type and hexagonal nanoplate shaped or NP type) and two different concentrations (0.07 M and 0.1 M) of manganese incorporated Co₃O₄@Mn_xCo_3-xO₄ core-shell nanoparticles (CSNs) were investigated, respectively. The motivation of this work is to investigate the magnetic properties of, and specifically the exchange bias, between different shaped CSNs and between different Mn-doped CSNs. A two-step synthesis method was utilized to obtain the CSNs: a soft chemical approach was used to obtain Co₃O₄ nanoparticles and a hydrothermal nano-phase epitaxy was used to …

Mitigating Accumulation Of Aeolian Dust Particles On Solar Power Generator Panels Without Water, Sanjana Das

UNLV Theses, Dissertations, Professional Papers, and Capstones

Accumulation of dust on solar panels poses a serious problem as it can significantly reduce light absorption and electrical energy output. Several factors affect the dust accumulation such as location, dust properties, wind velocity, system orientation, ambient temperature, humidity, and panel surface properties. Experimental and theoretical studies show that short circuit current and maximum power output of photovoltaic panels reduce approximately linearly with dust concentration. Incidentally, the locations with higher solar energy concentrations are also arid or semi-arid regions with higher dust concentrations. In order to avoid loss in power output, most PV installations perform periodic panel cleaning with water. …

Gold Nanoparticles For Stem Cell Delivery In Myocardial Infarction: Analysis Of Toxicity And Development Of A Cell Culture Platform For Use In An In-Vitro Model Of Mi-Associated Ischemia/Reperfusion, Jeffrey Curran Henson

Graduate Theses and Dissertations

In this work, the potential for PEGylated gold nanoparticles for use as a platform for stem cell delivery in treatment of myocardial infarction (MI) is preliminarily investigated. Cardiovascular disease is currently the leading cause of death worldwide, with majority of mortality resulting from coronary artery disease and associated MI. The ensuing ischemic conditions resulting from MI cause substantial heart muscle tissue loss and scarring in the heart. Adverse tissue remodeling creates a significant loss in heart function that can result in the formation of cardiac hypertrophy, ventricular dilation and arrythmias. The long-term prognosis of patients who have suffered MI is …

Editorial For The Special Issue On Micro/Nano-Chip Electrokinetics, Volume Ii, Xiangchun Xuan, Shizhi Qian

Mechanical & Aerospace Engineering Faculty Publications

There has been a rapidly increasing interest in the use of micro/nanofluidics to develop various point-of-care technologies for global health [1,2]. Electrokinetics is often the method of choice in these micro/nano-chips for an accurate transport and manipulation of fluids and samples [3,4]. This special issue in Micromachines is the continuation of our successful first volume on Micro/Nano-Chip Electrokinetics [5]. It consists of 22 contributions, which cover multiple aspects of electrokinetics related phenomena for various chemical and biological applications. We divide these papers into three primary categories and summarize them briefly below.

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 …

Bioengineering Of An In Vitro Microphysiological Human Alveolar Model, Ayesha Arefin

Nanoscience and Microsystems ETDs

Drugs tested on animal models do not always produce the same results in humans; a reliable in vitro lung model can bridge the divide between the two. Because the alveolus is a target for several drugs, an alveolar model can be a platform for both designing drugs and studying lung diseases. A model should allow for gas exchange, growth of primary alveolar epithelial cells, extracellular matrix production, and have similar mechanical properties to alveoli, creating an environment conducive to normal metabolic activity and cellular responses. Existing artificial alveolar models that use polymeric membranes to sustain lung cells are limited by …

Near-Field Heat Transfer Enabled Nanothermomechanical Memory And Logic Devices, Sidy Ndao, Mahmoud Elzouka

Department of Mechanical and Materials Engineering: Faculty Publications

A thermomechanical memory / logic device is disclosed . In embodiments , the thermomechanical device includes a first thermally controlled terminal ( e . g . , hot terminal ) ; a second thermally controlled terminal ( e . g . , cool terminal / base ) ; a stem or other structure that can be thermally expanded connected to the cool terminal ; and a thermal conductive head coupled to the stem . The head can exchange heat with the hot terminal . The stem and head are between the first thermally controlled terminal and the second thermally controlled …

Prevascularization Of 3d Printed Bone Scaffolds By Bioactive Hydrogels And Cell Co-Culture, Mitchell Kuss, Shaohua Wu, Ying Wang, Jason B. Untrauer, Wenlong Li, Jung Yul Lim, Bin Duan

Department of Mechanical and Materials Engineering: Faculty Publications

Vascularization is a fundamental prerequisite for large bone construct development and remains one of the main challenges of bone tissue engineering. Our current study presents the combination of 3D printing technique with a hydrogel-based prevascularization strategy to generate prevascularized bone constructs. Human adipose derived mesenchymal stem cells (ADMSC) and human umbilical vein endothelial cells (HUVEC) were encapsulated within our bioactive hydrogels, and the effects of culture conditions on in vitro vascularization were determined. We further generated composite constructs by forming 3D printed polycaprolactone/hydroxyapatite scaffolds coated with cell-laden hydrogels and determined how the co-culture affected vascularization and osteogenesis. It was demonstrated …

Smart Bandage For Monitoring And Treatment Of Chronic Wounds, Pooria Mostafalu, Ali Tamayol, Rahim Rahimi, Manuel Ochoa, Akbar Khalilpour, Gita Kiaee, Iman K. Yazdi, Sara Bagherifard, Mehmet R. Dokmeci, Babak Ziaie, Sameer R. Sonkusale, Ali Khademhosseini

Department of Mechanical and Materials Engineering: Faculty Publications

Chronic wounds are a major health concern and they affect the lives of more than 25 million people in the United States. They are susceptible to infection and are the leading cause of nontraumatic limb amputations worldwide. The wound environment is dynamic, but their healing rate can be enhanced by administration of therapies at the right time. This approach requires real-time monitoring of the wound environment with on-demand drug delivery in a closed-loop manner. In this paper, a smart and automated flexible wound dressing with temperature and pH sensors integrated onto flexible bandages that monitor wound status in real-time to …

The Effectiveness Of Localized Ultrasound And Aptamer Surface Modification On Nanoemulsions For Drug Delivery To Spheroids., Daniel A. Hodge

Electronic Theses and Dissertations

Cancer is a group of diseases that affects 1.6 million and kills nearly 600,000 Americans each year. The National Cancer Institute defines it as “diseases in which abnormal cells divide without control and can invade nearby tissues” and it is often treated with one or more of the following: chemotherapy, radiation, surgery. The expense for these treatments is expected to rise to $156 billion by 2020. Localized delivery can improve effectiveness and cancer survival rates, decrease the cost of treatment, and decrease the side effects of chemotherapy. This paper addresses models for this localized delivery through nanoemulsions. Nanoemulsions are a …

A New Approach To The Development Of An Rsv Anti-Viral Targeted Nanocarrier For Dual Inhibition Of Viral Infection And Replication, Anthony N. Singer

USF Tampa Graduate Theses and Dissertations

Respiratory Syncytial Virus (RSV) is a potentially life-threatening respiratory pathogen that infects approximately 64 million children and immunocompromised adults globally per year. Currently, there is a need for prophylactic and therapeutic approaches effective against primary and secondary RSV infections. This project focuses on the development of a simple, smart, and scalable anti-RSV nanotherapeutic that combines novel cellular antiviral defense mechanisms targeting the inhibition of viral fusion and replication. An ICAM-1 targeted liposomal nanocarrier will be synthesized and coated with a layer of chitosan containing the anti-fusion HR2-D peptide as an extracellular defense mechanism. Additionally, chitosan complexed to dual expressing short …

Migration Resistance Of Esophageal Stents: The Role Of Stent Design, Hozhabr Mozafari, Pengfei Dong, Shijia Zhao, Yonghua Bi, Xinwei Han, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

Objective: Stenting is one of the major treatments for malignant esophageal cancer. However, stent migration compromises clinical outcomes. A flared end design of the stent diminishes its migration. The goal of this work is to quantitatively characterize stent migration to develop new strategies for better clinical outcomes.

Methods: An esophageal stent with flared ends and a straight counterpart were virtually deployed in an esophagus with asymmetric stricture using the finite element method. The resulted esophagus shape, wall stress, and migration resistance force of the stent were quantified and compared.

Results: The lumen gain for both the flared stent and the …

Dft Study Of Water Assisted Hydrogen Dissociation On Gold Nanoparticles, Jia-Li Chen, Xia-Guang Zhang, De-Yin Wu, Zhong-Qun Tian

Journal of Electrochemistry

The gold nanoparticles (GNPs) show special activity toward hydrogen (H₂) dissociation, comparing with bulk gold. Such activity is significantly affected by the existence of water. To inspect the influence of water on GNPs catalyzed H₂ dissociation, we carried out density functional theory (DFT) calculations along the reaction paths for water clusters (H₂O)_m (m = 1, 2, 3, 7) assisted H₂ dissociation on gold clusters (Au_n^δ, n = 3 ~ 5; δ = 0, 1). Our calculated results show that water benefits to the H₂ dissociation. The dissociation mechanism varies …

Pt/G-C3N4 Nanosheet For Visible Light-Induced Enhancement Of The Activity For Formic Acid Electro-Oxidation, Yong-Rong Sun, Chun-Yu Du, Guo-Kang Han, Ya-Jing Wang, Yun-Zhi Gao, Ge-Ping Yin

Journal of Electrochemistry

By using graphitic carbon nitride nanosheet (g-C₃N₄ nanosheet) as a support,Pt/g-C₃N₄ nanosheet catalyst was fabricated by microwave assisted polylol process. The nanoparticles size,composition,structure and optical properties of Pt/g-C₃N₄ nanosheet were characterized by TEM,XRD,XPS and UV-Vis diffuse reflectance spectroscopy. Comparing with the catalytic activities toward formic acid electro-oxidation under dark and visible light illumination,the superior activity of Pt/g-C₃N₄ nanosheet catalyst was achieved under visible light illumination. This visible light-driven enhancement in the formic acid performance could be attributed to the plasmon-induced electron-hole separation on g-C₃N₄ with …