One-Dimensional Nanostructure And Sensing Applications: Tin Dioxide Nanowires And Carbon Nanotubes,
2016
Portland State University
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 …
Electrodeposition Of High Magnetostrictive Cobalt Iron Alloy Films For Smart Tags And Sensor Applications,
2016
University of New Mexico
Electrodeposition Of High Magnetostrictive Cobalt Iron Alloy Films For Smart Tags And Sensor Applications, Jamin Pillars
Nanoscience and Microsystems ETDs
Magnetostrictive CoFe films were investigated for use as magnetoelastic tags or sensors. The ability to electrodeposit these films enables batch fabrication processes to pattern a variety of geometries while controlling the film stoichiometry and crystallography. In current research looking at CoFe, improved magnetostriction was achieved using a co-sputtering, annealing, and quenching method1. Other current research has reported electrodeposited CoFe films using a sulfate based chemistry resulting in film compositions that are Fe rich in the range of Co0.3-0.4Fe0.7-0.6 and have problems of co-deposition of undesirables that can have a negative impact on magnetic properties2, 3. The research presented here focused …
Method For Hyper-Polarizing Nuclear Spns At Arbtrary Magnetic Felds,
2016
University of New Mexico
Method For Hyper-Polarizing Nuclear Spns At Arbtrary Magnetic Felds, Carlos A. Meriles, Daniela Pagliero, Abdelghani Laraoui
Department of Mechanical and Materials Engineering: Faculty Publications
A method of dynamically polarizing the nuclear spin host of nitrogen-vacancy (NV) centers in diamond is provided. The method uses optical, microwave and radio-frequency pulses to recursively transfer spin polarization from the NV electronic spin. Nitrogen nuclear spin initialization approaching 80% at room temperature is demonstrated both in ensemble and single NV centers without relying on level anti-crossings. This makes the method applicable at arbitrary magnetic fields.
Dlvo Approximation Methods For Predicting The Attachment Of Silver Nanoparticles To Ceramic Membranes,
2016
Marshall University
Dlvo Approximation Methods For Predicting The Attachment Of Silver Nanoparticles To Ceramic Membranes, Anne M. Mikelonis, Sungmin Youn, Desmond F. Lawler
All Engineering Faculty Research
This article examines the influence of three common stabilizing agents (citrate, poly(vinylpyrrolidone) (PVP), and branched poly(ethylenimine) (BPEI)) on the attachment affinity of silver nanoparticles to ceramic water filters. Citrate-stabilized silver nanoparticles were found to have the highest attachment affinity (under conditions in which the surface potential was of opposite sign to the filter). This work demonstrates that the interaction between the electrical double layers plays a critical role in the attachment of nanoparticles to flat surfaces and, in particular, that predictions of double-layer interactions are sensitive to boundary condition assumptions (constant charge vs constant potential). The experimental deposition results can …
Optimization Of Transition-Metal Dichalcogenides Based Field- Effect- Transistors Via Contact Engineering,
2016
Wayne State University
Optimization Of Transition-Metal Dichalcogenides Based Field- Effect- Transistors Via Contact Engineering, Meeghage Madusanka Perera
Wayne State University Dissertations
ABSTRACT
Optimization of Transition-Metal Dichalcogenides based Field- Effect-Transistors via contact engineering
by
Meeghage M Perera
September , 2016
Advisor : Dr. Zhixian Zhou
Major: Physics (Condensed mater physics/nano-electronics)
Degree: Doctor of Philosophy
Layered transition Metal Dichalcogenides (TMDs) have demonstrated a wide range of remarkable properties for applications in next generation nano-electronics. These systems have displayed many “graphene-like” properties including a relatively high carrier mobility, mechanical flexibility, chemical and thermal stability, and moreover offer the significant advantage of a substantial band gap. However, the fabrication of high performance field-effect transistors (FETs) of TMDs is challenging mainly due to the formation of …
Modeling And Simulation Of Optical Properties Of Noble Metals Triangular Nanoprisms,
2016
University of Denver
Modeling And Simulation Of Optical Properties Of Noble Metals Triangular Nanoprisms, Soad Zahir Alsheheri
Electronic Theses and Dissertations
Gold and silver has gained huge attention across the scientific community for its applications arising from its plasmonic properties. The optical properties achieved by these materials via excitation of plasmons is very unique to these materials and used as diagnostic and therapeutic agents in the field of medicine, and as sensors in a gamut of disciplines such as energy and environmental protection to name a few. Surface plasmon resonance (SPR) properties of the gold and silver are size and shape dependent. Of the various shapes reported in literature, triangular nanoprisms has tunable optical properties in the visible and near IR …
Temperature-Dependent Helium Ion-Beam Mixing In An Amorphous Sioc/Crystalline Fe Composite,
2016
University of Nebraska-Lincoln
Temperature-Dependent Helium Ion-Beam Mixing In An Amorphous Sioc/Crystalline Fe Composite, Qing Su, Lloyd Price, Lin Shao, Michael Nastasi
Department of Mechanical and Materials Engineering: Faculty Publications
Temperature dependent He-irradiation-induced ion-beam mixing between amorphous silicon oxycarbide (SiOC) and crystalline Fe was examined with a transmission electron microscope (TEM) and via Rutherford backscattering spectrometry (RBS). The Fe marker layer (7.2 ± 0.8 nm) was placed in between two amorphous SiOC layers (200 nm). The amount of ion-beam mixing after 298, 473, 673, 873, and 1073 K irradiation was investigated. Both TEM and RBS results showed no ion-beam mixing between Fe and SiOC after 473 and 673 K irradiation and a very trivial amount of ion-beam mixing (~2 nm) after 298 K irradiation. At irradiation temperatures higher than 873 …
New Approaches To Chalcogenide Materials For Thermoelectrics: Lead Telluride-Based Nanostructures And Facile Synthesis Of Tetrahedrite And Doped Derivatives,
2016
Wayne State University
New Approaches To Chalcogenide Materials For Thermoelectrics: Lead Telluride-Based Nanostructures And Facile Synthesis Of Tetrahedrite And Doped Derivatives, Derak Justin James
Wayne State University Dissertations
The overall purpose of this work is to address several of the roadblocks to use of thermoelectric materials for generation of electricity, namely inefficient processing of materials and low performance, commonly rated by the figure of merit, ZT=T2/tot. The ZT includes as the Seebeck coefficient, as electrical resistivity, T as the average temperature, and tot as total thermal conductivity. tot is the sum of electronic charge carrier (C) and lattice (L) contributions to thermal conductivity. Attempts to increase ZT in the literature to values >1 have focused on decreasing the thermal conductivity via nanostructuring or optimizing the electrical …
Novel Design And Synthesis Of Structured Iron Oxides For Battery Applications,
2016
Wayne State University
Novel Design And Synthesis Of Structured Iron Oxides For Battery Applications, Jian Zhu
Wayne State University Dissertations
Lithium-ion batteries (LIBs) are currently the dominant powder source for personal computers and portable electronics. LIBs also play important roles in larger-scale applications, including electric drive vehicles (EVs, HEVs) and grid-energy storage. To meet the increasing demand for energy storage, it is very urgent and crucial to develop next-generation LIBs using alternative electrode materials. For example, carbon is still exclusively used as anode materials in current LIBs. However, the theoretical capacity of graphite (372 mA h g–1 based on LiC6) has almost been achieved, and it becomes one of the bottlenecks to further increase the energy density of LIBs based …
Active Stiffening Of F-Actin Network Dominated By Structural Transition Of Actin Filaments Into Bundles,
2016
University of Nebraska-Lincoln
Active Stiffening Of F-Actin Network Dominated By Structural Transition Of Actin Filaments Into Bundles, Shengmao Lin, Xinwei Han, Gary C.P. Tsui, David Hui, Linxia Gu
Department of Mechanical and Materials Engineering: Faculty Publications
Molecular motor regulated active contractile force is key for cells sensing and responding to their mechanical environment, which leads to characteristic structures and functions of cells. The F-actin network demonstrates a two-order of magnitude increase in its modulus due to contractility; however, the mechanism for this active stiffening remains unclear. Two widely acknowledged hypotheses are that active stiffening of F-actin network is caused by (1) the nonlinear force-extension behavior of cross-linkers, and (2) the loading mode being switched from bending to stretching dominated regime. Direct evidence supporting either theory is lacking. Here we examined these hypotheses and showed that a …
Study Of Role Of Meniscus And Viscous Forces During Liquid-Mediated Contacts Separation,
2016
Minnesota State University Mankato
Study Of Role Of Meniscus And Viscous Forces During Liquid-Mediated Contacts Separation, Prabin Dhital
All Graduate Theses, Dissertations, and Other Capstone Projects
Menisci may form between two solid surfaces with the presence of an ultra-thin liquid film. When the separation operation is needed, meniscus and viscous forces contribute to an adhesion leading stiction, high friction, possibly high wear and potential failure of the contact systems, for instance microdevices, magnetic head disks and diesel fuel injectors. The situation may become more pronounced when the contacting surfaces are ultra-smooth and the normal load is small. Various design parameters, such as contact angle, initial separation height, surface tension and liquid viscosity, have been investigated during liquid-mediated contact separation. However, how the involved forces will change …
Thermodynamics And Kinetics Of The Three-Way Junction Of Phi29 Motor Prna And Its Assembly Into Nanoparticles For Therapeutic Delivery To Prostate Cancer,
2016
University of Kentucky
Thermodynamics And Kinetics Of The Three-Way Junction Of Phi29 Motor Prna And Its Assembly Into Nanoparticles For Therapeutic Delivery To Prostate Cancer, Daniel W. Binzel
Theses and Dissertations--Pharmacy
The emerging field of RNA nanotechnology necessitates creation of functional RNA nanoparticles, but has been limited by particle instability. Previously, it was found the three-way junction (3WJ) of the Phi29 DNA packaging motor pRNA was found to be ultra-stable and assemble in solution without the presence of metal ions. The three-way junction is composed of three short oligo RNA strands and proven to be thermodynamically stable. Here the assembly mechanism, thermodynamic and enzymatic stabilities, and kinetics are examined in order to understand the stability behind this unique motif. Thermodynamic and kinetics studies found that the pRNA 3WJ formed out of …
Tailoring Optical And Plasmon Resonances In Core-Shell And Core-Multishell Nanowires,
2016
Purdue University
Tailoring Optical And Plasmon Resonances In Core-Shell And Core-Multishell Nanowires, Sarath Ramadurgam
Open Access Dissertations
Semiconductor nanowires (NWs) are sub-wavelength structures which exhibit strong optical (Mie) resonances in the visible range. In addition to such optical resonances, the localized surface plasmon resonances (LSPR) in metal and semiconductor (or dielectric) based core-shell (CS) and core-multishell (CMS) NWs can be tailored to achieve novel negative-index metamaterials (NIM), extreme absorbers, invisibility cloaks and sensors. Particularly, in this dissertation, the versatility of CS and CMS NWs for the design of negative-index metamaterials in the visible range and, plasmonic light harvesting in ultrathin photocatalyst layers for water splitting are studied.
Utilizing the LSPR in the metal layer and the magnetic …
Protein-Targeted Corona Phase Molecular Recognition,
2016
Massachusetts Institute of Technology
Protein-Targeted Corona Phase Molecular Recognition, Gili Bisker, Juyao Dong, Hoyoung D. Park, Nicole M. Iverson, Jiyoung Ahn, Justin T. Nelson, Markita P. Landry, Sebastian Kruss, Michael S. Strano
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Corona phase molecular recognition (CoPhMoRe) uses a heteropolymer adsorbed onto and templated by a nanoparticle surface to recognize a specific target analyte. This method has not yet been extended to macromolecular analytes, including proteins. Herein we develop a variant of a CoPhMoRe screening procedure of single-walled carbon nanotubes (SWCNT) and use it against a panel of human blood proteins, revealing a specific corona phase that recognizes fibrinogen with high selectivity. In response to fibrinogen binding, SWCNT fluorescence decreases by >80% at saturation. Sequential binding of the three fibrinogen nodules is suggested by selective fluorescence quenching by isolated sub-domains and validated …
Impedance Characterization Of Ysz Based Nox Sensors,
2016
Louisiana Tech University
Impedance Characterization Of Ysz Based Nox Sensors, Ling Cui
Doctoral Dissertations
Yttria-stabilized zirconia has been utilized as an electrolyte of SOFC (Solid Oxide Fuel Cell) studies for years. It is also preferred as the electrolyte for solid state electrochemical sensor which is able to measure nitrogen oxides in the exhaust system. Electrochemical Impedance Spectroscopy method yields the change in impedance which is caused by an electron exchange of NO x gases at the sensing electrodes. From the EIS data, the fractional change in the phase angle is calculated for detecting sensor sensitivity.
Considering the fabrication of a sensor, several variables have been investigated which include the choice of electrolyte processing, sensing …
Size Specific Transfection To Mammalian Cells By Micropillar Array Electroporation,
2016
Louisiana Tech University
Size Specific Transfection To Mammalian Cells By Micropillar Array Electroporation, Yingbo Zu
Doctoral Dissertations
Electroporation serves as a promising non-viral gene delivery approach, while its current configurations carry drawbacks associated with high-voltage electrical pulses and heterogeneous treatment on individual cells. Here, we developed a new micropillar array electroporation (MAE) platform to advance the delivery of plasmid DNA and RNA to mammalian cells. By introducing well-patterned micropillar array on the electrode surface, the number of pillars each cell faces varies with its cell membrane surface area, despite their large population and random locations. In this way, cell size specific electroporation is conveniently done and contributed to a 2.5~3 fold increase on plasmid DNA transfection and …
Synthesis, Device Fabrication, And Characterization Of Two-Dimensional Molybdenum Disulfide,
2016
University of Texas at El Paso
Synthesis, Device Fabrication, And Characterization Of Two-Dimensional Molybdenum Disulfide, Gustavo Alberto Lara Saenz
Open Access Theses & Dissertations
The miniaturization of electronic devices according to Moore's Law has been propelled by the continuous demand for faster and smaller devices which continue to advance technology. One recent contribution to this trend was the isolation and characterization of one atom thick of graphite, known as graphene, which led to the Nobel Prize in physics in 2010 being awarded to Andre Geim and Konstantin Novoselov. Graphene and its related nanocarbon derivatives have exceptional mechanical, thermal, optical and electronic properties, making them a potential candidate for electronics and optoelectronics applications. However, this material has no intrinsic bandgap and complicated processes are required …
Implementation Of New System For Oxygen Generation And Carbon Dioxide Removal,
2016
University of Texas at El Paso
Implementation Of New System For Oxygen Generation And Carbon Dioxide Removal, Angelo Peter Karavolos
Open Access Theses & Dissertations
This research effort develops an integrated system for CO2 removal and O2 production. A unique material, dodeca-tungsto-phosphoric acid (H3PO4W12O3; henceforth referred to as DTPA) is mixed with tetra-ethyl-ortho-silicate Si(OC2H5)4 or TEOS. This mixture exhibits unique properties of heat absorption and high electrical conductivity. In the system described herein, the DTPA resides within a cross linked arrangement of TEOS. The DTPA furnishes a source of O2, while the TEOS furnishes structural support for the large DTPA crystals. In addition, the large amount of H2O within the crystal also adsorbs CO2. It can also be cross-linked with other polymers such as polycarbonate, …
Liquid-Phase Exfoliation Of Two-Dimensional Graphite For Ink-Jet Printing,
2016
University of Texas at El Paso
Liquid-Phase Exfoliation Of Two-Dimensional Graphite For Ink-Jet Printing, Monica Michel
Open Access Theses & Dissertations
Over the last decade, the study of two-dimensional (2D) materials has seen an incredible growth due to their unique thermal, mechanical and electronic properties. Solution phase manufacturing offers a way in which they can be produced at large scale by creating dispersions from the exfoliated material. Once created, different options for assembling devices exist. One technique for large scale manufacturing of materials in this form is ink-jet printing, which is a form of additive manufacturing that has proven to be attractive for the printed electronics industry. One challenge that ink-jet printing still faces is the shortage of inks with appropriate …
Low Temperature Solution-Processed Sb:Sno2
Nanocrystals For Efficient Planar Perovskite Solar Cells,
2016
University of Nebraska-Lincoln
Low Temperature Solution-Processed Sb:Sno2 Nanocrystals For Efficient Planar Perovskite Solar Cells, Yang Bai, Yanjun Fang, Yehao Deng, Qi Wang, Jingjing Zhao, Xiaopeng Zheng, Yang Zhang, Jinsong Huang
Department of Mechanical and Materials Engineering: Faculty Publications
Inorganic metal oxide electron-transport layers (ETLs) have the potential to yield perovskite solar cells with improved stability, but generally need high temperature to form conductive and defect-less forms, which is not compatible with the fabrication of flexible and tandem solar cells. Here, we demonstrate a facile strategy for developing efficient inorganic ETLs by doping SnO2 nanocrystals (NCs) with a small amount of Sb using a low-temperature solution-processed method. The electrical conductivity was remarkably enhanced by Sb-doping, which increased the carrier concentration in Sb:SnO2 NCs. Moreover, the upward shift of the Fermi level owing to doping results in improved …
