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Articles 1 - 11 of 11

Full-Text Articles in Physical Sciences and Mathematics

Ferroelectric And Ferromagnetic Nanofibers: Synthesis, Properties And Applications, A Jalalian, A M. Grishin, S X. Dou Jun 2013

Ferroelectric And Ferromagnetic Nanofibers: Synthesis, Properties And Applications, A Jalalian, A M. Grishin, S X. Dou

Shi Xue Dou

As first time, ferroelectric (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 (BCTZ), biocompatible (Na0.5K0.5)NbO3 (NKN), and ferromagnetic Y3Fe5O12 (YIG) nanofibers were synthesized by sol-gel assisted electrospining technique. Non-woven, bead-free 100 μm long fiber mat was formed from close-packed nanocrystals after calcination in air at 800°C (BCTZ and NKN) and 1100°C (YIG). BCTZ fibers are 200 nm in width whereas NKN and YIG fibers have smaller 50-100 nm diameter. X-ray diffraction and Raman spectroscopy show that BCTZ and NKN crystallized in tetragonal and rhombohedral polar phases in the vicinity of morphotropic phase boundary. Room temperature ferromagnetism in YIG fibers is indicated by a well formed M-H hysteresis …


Traffic Modeling In Lagrangian Coordinates Using Smartphone Apps, Sergio Contreras May 2013

Traffic Modeling In Lagrangian Coordinates Using Smartphone Apps, Sergio Contreras

UNLV Theses, Dissertations, Professional Papers, and Capstones

Traditionally, one of the ways traffic flow has been studied is by using the kinematic wave model. This model is derived in the Eulerian framework by using conservation of the number of vehicles. Recently, the kinematic wave model has been transformed into Lagrangian coordinates. In this framework, the independent variables are unique

vehicles and time. The detailed change in framework, and the properties of the model in the changed framework are reviewed. Numerical results from different traffic cases are explained. Since vehicle trajectory data can be easily collected from smartphones,

a smartphone application is developed for this purpose. This data …


Polypyrrole Coated Nylon Lycra Fabric As Stretchable Electrode For Supercapacitor Applications, Binbin Yue, Caiyun Wang, Xin Ding, Gordon G. Wallace Mar 2013

Polypyrrole Coated Nylon Lycra Fabric As Stretchable Electrode For Supercapacitor Applications, Binbin Yue, Caiyun Wang, Xin Ding, Gordon G. Wallace

Gordon Wallace

Wearable electronics offer the combined advantages of both electronics and fabrics. Being an indispensable part of these electronics, lightweight, stretchable and wearable power sources are strongly demanded. Here we describe a daily-used nylon lycra fabric coated with polypyrrole as electrode for stretchable supercapacitors. Polypyrrole was synthesized on the fabric via a simple chemical polymerization process with ammonium persulfate (APS) as an oxidant and naphthalene-2,6-disulfonic acid disodium salt (Na2NDS) as a dopant. This material was characterized with FESEM, FTIR, tensile stress, and studied as a supercapacitor electrode in 1.0 M NaCl. This conductive textile could endure 1000 stretching cycles with 100% …


Novel Microwave Assisted Synthesis Of Zns Nanomaterials, Suresh Pillai, Michael Seery, Damian Synnott, John Colreavy, Stephen Hinder Jan 2013

Novel Microwave Assisted Synthesis Of Zns Nanomaterials, Suresh Pillai, Michael Seery, Damian Synnott, John Colreavy, Stephen Hinder

Articles

A novel ambient pressure microwave-assisted technique is developed in which silver and indium modified ZnS is synthesised. The as prepared ZnS is characterised by X-ray diffraction, UV-Vis spectroscopy, X-ray photoelectron spectroscopy and luminescence spectroscopy. This procedure produced crystalline materials with particle sizes below 10 nm. The synthesis technique leads to defects in the crystal which induce mid energy levels in the band gap and lead to indoor light photocatalytic activity. Increasing the amount of silver causes a phase transition from cubic blende to hexagonal phase ZnS. In a comparative study, when the ZnS cubic blende is heated in a conventional …


1-3 Piezoelectric Composites For High-Temperature Transducer Applications, Lili Li, Shujun Zhang, Zhuo Xu, Fei Wen, Xuecang Geng, Hyeong Jae Lee, Thomas R. Shrout Jan 2013

1-3 Piezoelectric Composites For High-Temperature Transducer Applications, Lili Li, Shujun Zhang, Zhuo Xu, Fei Wen, Xuecang Geng, Hyeong Jae Lee, Thomas R. Shrout

Australian Institute for Innovative Materials - Papers

High-temperature Pb(Zr,Ti)O3/epoxy 1-3 composites were fabricated using the dice and fill method. The epoxy filler was modified with glass spheres in order to improve the thermal reliability of the composites at elevated temperatures. Temperature-dependent dielectric and electromechanical properties of the composites were measured after ageing at 250 °C with different dwelling times. Obvious cracks were observed and the electrodes were damaged in the composite with unmodified epoxy after 200 h, leading to the failure of the composite. In contrast, composites with >12 vol% glass sphere loaded epoxies were found to exhibit minimal electrical property variation after ageing for 500 h, …


Inkjet Printed Conductive Polymer-Based Beam-Splitters For Terahertz Applications, Benjamin S-Y Ung, Bo Weng, Roderick L. Shepherd, Derek Abbott, Christopher Fumeaux Jan 2013

Inkjet Printed Conductive Polymer-Based Beam-Splitters For Terahertz Applications, Benjamin S-Y Ung, Bo Weng, Roderick L. Shepherd, Derek Abbott, Christopher Fumeaux

Australian Institute for Innovative Materials - Papers

Terahertz beam-splitters are fabricated from conductive polymers inkjet printed onto an acetate film substrate. The principle is a significant evolution of the recently proposed ultra-thin beam-splitter realized using silver conductive paint. The splitting ratios of the beam-splitters are dependent on the thickness and conductivity of the conductive polymer layer, allowing for any splitting ratio to be achieved accurately from a controlled printing process. As the processing technology of conductive polymers matures, this approach will allow for low cost and accurate fabrication of THz beam-splitters with a predefined near frequency-independent splitting ratio, in contrast to the commonly used float zone silicon …


Multifunctional Conducting Polymer Fibres For Drug Delivery Applications, Dorna Esrafilzadeh, Simon E. Moulton, Joselito M. Razal, Elise M. Stewart, Gordon G. Wallace Jan 2013

Multifunctional Conducting Polymer Fibres For Drug Delivery Applications, Dorna Esrafilzadeh, Simon E. Moulton, Joselito M. Razal, Elise M. Stewart, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Advances in the fabrication of neuroprosthetic electrodes have attracted considerable interest from biomedical researchers. These electrodes are incorporated into a neuroprosthetic device capable of, electrically stimulating and recording of neuron activity. Critical to the successful application of these electrodes is their biocompatibility, stable conductivity, lower impedance and flexibility whilst maintaining appropriate mechanical properties [1] .


Carbon Nanotube-Reduced Graphene Oxide Composites For Thermal Energy Harvesting Applications, Mark S. Romano, Na Li, Dennis Antiohos, Joselito M. Razal, Andrew Nattestad, Stephen Beirne, Shaoli Fang, Yongsheng Chen, Rouhollah Jalili, Gordon G. Wallace, Ray Baughman, Jun Chen Jan 2013

Carbon Nanotube-Reduced Graphene Oxide Composites For Thermal Energy Harvesting Applications, Mark S. Romano, Na Li, Dennis Antiohos, Joselito M. Razal, Andrew Nattestad, Stephen Beirne, Shaoli Fang, Yongsheng Chen, Rouhollah Jalili, Gordon G. Wallace, Ray Baughman, Jun Chen

Australian Institute for Innovative Materials - Papers

By controlling the SWNT-rGO electrode composition and thickness to attain the appropriate porosity and tortuosity, the electroactive surface area is maximized while rapid diffusion of the electrolyte through the electrode is maintained. This leads to an increase in exchange current density between the electrode and electrolyte which results in enhanced thermocell performance.


Manganosite-Microwave Exfoliated Graphene Oxide Composites For Asymmetric Supercapacitor Device Applications, Dennis Antiohos, Kanlaya Pingmuang, Mark Romano, Stephen Beirne, Tony C. Romeo, Phil Aitchison, Andrew I. Minett, Gordon G. Wallace, Sukon Phanichphant, Jun Chen Jan 2013

Manganosite-Microwave Exfoliated Graphene Oxide Composites For Asymmetric Supercapacitor Device Applications, Dennis Antiohos, Kanlaya Pingmuang, Mark Romano, Stephen Beirne, Tony C. Romeo, Phil Aitchison, Andrew I. Minett, Gordon G. Wallace, Sukon Phanichphant, Jun Chen

Australian Institute for Innovative Materials - Papers

Graphene based materials coupled with transition metal oxides are promising electrode materials in asymmetric supercapacitors owing to their unique properties which include high surface area, good chemical stability, electrical conductivity, abundance, and lower cost profile over time. In this paper a composite material consisting of graphene oxide exfoliated with microwave radiation (mw rGO), and manganosite (MnO) is synthesised in order to explore their potential as an electrode material. The composite material was characterised by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to explore …


Review On Shear Thickening Fluids And Applications, Jie Ding, Phillip J. Tracey, Weihua Li, Gangrou Peng, Philip G. Whitten, Gordon G. Wallace Jan 2013

Review On Shear Thickening Fluids And Applications, Jie Ding, Phillip J. Tracey, Weihua Li, Gangrou Peng, Philip G. Whitten, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Recently, research in the area of shear thickening fluids (STFs) has increased due to the potential for commercial application. They are considered possible candidate materials for liquid body armour and sporting protective clothing and other applications because of their unique properties. Here the state of the art of shear thickening mechanisms, ingredient materials, fabrication methods, rheological properties, and factors influencing shear thickening behaviour have been reviewed. Basic models used to describe shear thickening behavior are also discussed. Relevant patent applications, particularly in the area of body armour, as well as other industrial applications, such as smart structures, and devices with …


Applications Of Voltammetric Ion Selective Electrodes To Complex Matrices, Alexander R. Harris, Jie Zhang, Robert W. Cattrall, Alan M. Bond Jan 2013

Applications Of Voltammetric Ion Selective Electrodes To Complex Matrices, Alexander R. Harris, Jie Zhang, Robert W. Cattrall, Alan M. Bond

Australian Institute for Innovative Materials - Papers

The practical application of two different voltammetric ion selective electrodes (VISE) to measure ion activity in complex solutions has been explored. 7,7,8,8-tetracyanoquinodimethane (TCNQ) and tetrathiafulvalene (TTF) microcrystals adhered to an electrode surface act as a low selectivity voltammetric ion sensor. Resistance drop effects and pH artifacts were minimised by the addition of an "innocent" supporting electrolyte (buffer) to the analyte solution. In this format, addition of an ionophore to improve selectivity resulted in a reduction in current magnitude, due to competition for the ion. In contrast, voltammetry of a thin film containing a redox active species, electrolyte, ionophore and membrane …