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University of Wollongong

Characterization

Articles 1 - 11 of 11

Full-Text Articles in Physical Sciences and Mathematics

Probe Current Determination In Analytical Tem/Stem And Its Application To The Characterization Of Large Area Eds Detectors, David R. G Mitchell, Mitchell John Bromley Nancarrow Jan 2015

Probe Current Determination In Analytical Tem/Stem And Its Application To The Characterization Of Large Area Eds Detectors, David R. G Mitchell, Mitchell John Bromley Nancarrow

Australian Institute for Innovative Materials - Papers

A simple procedure, which enables accurate measurement of transmission electron microscopy (TEM)/STEM probe currents using an energy loss spectrometer drift tube is described. The currents obtained are compared with those measured on the fluorescent screen to enable the losses due to secondary and backscattered electrons to be determined. The current values obtained from the drift tube allow the correction of fluorescent screen current densities to yield true current. They also enable CCD conversion efficiencies to be obtained, which in turn allows images to be calibrated in terms of electron fluence. Using probes of known current in conjunction with a NiO …


Development And Characterization Of Novel Hybrid Hydrogel Fibers, Azadeh Mirabedini, Javad Foroughi, Anthony C. Romeo, Gordon G. Wallace Jan 2015

Development And Characterization Of Novel Hybrid Hydrogel Fibers, Azadeh Mirabedini, Javad Foroughi, Anthony C. Romeo, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Biopolymeric continuous core-sheath fibres, with an inner core of chitosan and alginate as the sheath, were fabricated for the first time without using a template. Hereby, the necessary conditions to achieve chitosan-alginate core-sheath fibre via a wet-spinning process are presented. SEM micrographs show the cylinder-shaped monofilament structure of the chitosan core surrounded by the alginate sheath. The coaxial fibres exhibit a 260% increase in ultimate stress and more than 300% enhancement in the Young's modulus compared to the alginate counterpart. Release profiles from the coaxial fibre were determined using a model component. The obtained results suggest that the fibres are …


Applications Of Scanning Electrochemical Microscopy (Secm) For Local Characterization Of Az31 Surface During Corrosion In A Buffered Media, Sina S. Jamali, Simon E. Moulton, Dennis E. Tallman, Maria Forsyth, Jan Weber, Gordon G. Wallace Jan 2014

Applications Of Scanning Electrochemical Microscopy (Secm) For Local Characterization Of Az31 Surface During Corrosion In A Buffered Media, Sina S. Jamali, Simon E. Moulton, Dennis E. Tallman, Maria Forsyth, Jan Weber, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Different modes of scanning electrochemical mapping (SECM) such as surface generation/tip collection (SG/TC), amperometry, AC-SECM and potentiometry were employed to characterize the active/passive domains, hydrogen gas (H2) evolution and local pH on a corroding surface of AZ31 in simulated biological fluid (SBF). It was found that the main domains of H2 evolution are associated with lower insulating properties of the surface as well as higher local pH. The near surface pH was found to be highly alkaline indicating that, even in a buffered solution such as SBF, the local pH on a corroding AZ31 surface can be significantly different to …


Porous Ni0.5zn0.5fe2o4 Nanospheres: Synthesis, Characterization, And Application For Lithium Storage, Min Zhang, Xuanwen Gao, Zhenfa Zi, Jianming Dai, Jiazhao Wang, Shulei Chou, Changhao Liang, Xuebin Zhu, Yuping Sun, Hua-Kun Liu Jan 2014

Porous Ni0.5zn0.5fe2o4 Nanospheres: Synthesis, Characterization, And Application For Lithium Storage, Min Zhang, Xuanwen Gao, Zhenfa Zi, Jianming Dai, Jiazhao Wang, Shulei Chou, Changhao Liang, Xuebin Zhu, Yuping Sun, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Monodisperse porous Ni0.5Zn0.5Fe2O4 nanospheres have been successfully synthesized by the solvothermal method. The diameter of the nanospheres can be tuned by controlling the reactant concentration. Lower reactant concentration is favoured for the synthesis of mesoporous Ni0.5Zn0.5Fe2O4 nanospheres with higher surface area. The electrochemical results show that mesoporous Ni0.5Zn0.5Fe2O4 nanospheres exhibit high reversible specific capacity (1110 mAh g-1) for Li storage and high capacity retention, with 700 mAh g-1 retained up to 50 cycles. The excellent electrochemical properties could be attributed to the large surface area and mesoporous structure. The results suggest that Ni0.5Zn0.5Fe2O4 could be a promising high capacity anode …


Dispersion And Characterization Of Arc Discharge Single-Walled Carbon Nanotubes-Towards Conducting Transparent Films, Benedikt Rosner, Dirk Guldi, Jun Chen, Andrew Minett, Rainer H. Fink Jan 2014

Dispersion And Characterization Of Arc Discharge Single-Walled Carbon Nanotubes-Towards Conducting Transparent Films, Benedikt Rosner, Dirk Guldi, Jun Chen, Andrew Minett, Rainer H. Fink

Australian Institute for Innovative Materials - Papers

This study addresses a combination of a well-developed and mild dispersion method and high-quality arc discharge single-walled carbon nanotubes (SWCNTs) as starting materials. Thus, we advance in fabrication of transparent, conducting films with extraordinary low material loss during SWCNT processing. The starting material was characterized by means of thermogravimetric analysis, high-resolution transmission electron microscopy and Raman spectroscopy. The quality of the starting material and produced dispersions was evaluated by ultraviolet and visible light absorption spectroscopy and Raman spectroscopy. A transparent conductive film was fabricated by drop-casting, whereas films were obtained with electrical to optical conductivity ratios (σDC/σOp) as high as …


Microwave Characterization Of Carbon Nanotube Yarns For Uwb Medical Wireless Body Area Networks, Syed Muzahir Abbas, Oya Sevimli, Michael C. Heimlich, Karu P. Esselle, B Kimiaghalam, Javad Foroughi, Farzad Safaei Jan 2013

Microwave Characterization Of Carbon Nanotube Yarns For Uwb Medical Wireless Body Area Networks, Syed Muzahir Abbas, Oya Sevimli, Michael C. Heimlich, Karu P. Esselle, B Kimiaghalam, Javad Foroughi, Farzad Safaei

Australian Institute for Innovative Materials - Papers

Carbon nanotube (CNT) yarns are novel CNT-based materials that extend the advantages of CNT from the nanoscale to macroscale applications. In this study, we have modeled CNT yarns as potential data transmission lines. Test structures have been designed to measure electrical properties of CNT yarns, which are attached to these test structures using gold paste. DC testing and microwave S-parameter measurements have been conducted for characterization. The observed frequency independent resistive behavior of the CNT yarn is a very promising indicator that this material, with its added values of mechanical resilience and thermal conductivity, could be invaluable for a range …


The Detailed Characterization Of Electrochemically Switchable Molecular Assemblies On Silicon Electrodes, Simone Ciampi, Michael James, Moinul H. Choudhury, Nadim A. Darwish, J Justin Gooding Jan 2013

The Detailed Characterization Of Electrochemically Switchable Molecular Assemblies On Silicon Electrodes, Simone Ciampi, Michael James, Moinul H. Choudhury, Nadim A. Darwish, J Justin Gooding

Australian Institute for Innovative Materials - Papers

In this paper we explore a multi-step synthetic strategy toward fabrication of monolayer-modified Si(100) electrodes that can be electrochemically switched. The synthetic scheme is modular and benefits from an established intramolecular lactonization scheme of benzoquinone analogs. A redox-tagged pendant group can be released from the surface such as to allow for in situ monitoring of the switch process. We show that this model system can be used to elucidate chemical and structural events for a surface dynamic system that is rapidly gaining popularity. The influence of polarization times, overpotentials and semiconductor doping type on the kinetic of the switch event …


Novel Nanographene/Porphyrin Hybrids-Preparation, Characterization, And Application In Solar Energy Conversion Schemes, Daniel Kiessling, Ruben D. Costa, Georgios Katsukis, Jenny Malig, Fabian Lodermeyer, Sebastian Feihl, Alexandra Roth, Leonie Wibmer, Matthias Kehrer, Michel Volland, Pawel W. Wagner, Gordon G. Wallace, David L. Officer, Dirk M. Guldi Jan 2013

Novel Nanographene/Porphyrin Hybrids-Preparation, Characterization, And Application In Solar Energy Conversion Schemes, Daniel Kiessling, Ruben D. Costa, Georgios Katsukis, Jenny Malig, Fabian Lodermeyer, Sebastian Feihl, Alexandra Roth, Leonie Wibmer, Matthias Kehrer, Michel Volland, Pawel W. Wagner, Gordon G. Wallace, David L. Officer, Dirk M. Guldi

Australian Institute for Innovative Materials - Papers

Four novel nanographene/porphyrin hybrids were prepared, characterized, and probed in solar energy conversion schemes. Exfoliation of graphite by means of immobilizing four different porphyrins onto the basal plane of graphene is accompanied by distinct electronic interactions in both the ground and the excited states. In the ground state, a strong loss in oscillator strength goes hand-in-hand with a notable broadening of the porphyrin transitions and, as such, attests to the shift of electron density from the electron donating porphyrins to nanographene. In the excited state, a nearly quantitative quenching of the porphyrin fluorescence is indicative of full charge transfer. The …


Material Characterization At Low Frequencies Using Thz And Raman Spectroscopy, Y Kutuvantavida, G V M Williams, E M. Pogson, D Bhuiyan, K Radhanpura, Roger A. Lewis Jan 2012

Material Characterization At Low Frequencies Using Thz And Raman Spectroscopy, Y Kutuvantavida, G V M Williams, E M. Pogson, D Bhuiyan, K Radhanpura, Roger A. Lewis

Australian Institute for Innovative Materials - Papers

We present results from wideband THz, low wave-number Raman, and FTIR measurements on benzoic acid and two of its derivatives. The low energy vibrational modes have been identified and compared with the results from calculations.


Synthesis And Electrochemical Characterization Of Lifepo4/C-Polypyrrole Composite Prepared By A Simple Chemical Vapor Deposition Method, Qiang Gong, Yu-Shi He, Yang Yang, Xiao Zhen Liao, Zi-Feng Ma Jan 2012

Synthesis And Electrochemical Characterization Of Lifepo4/C-Polypyrrole Composite Prepared By A Simple Chemical Vapor Deposition Method, Qiang Gong, Yu-Shi He, Yang Yang, Xiao Zhen Liao, Zi-Feng Ma

Australian Institute for Innovative Materials - Papers

A LiFePO4/C-polypyrrole (LiFePO4/C-PPy) composite as a high-performance cathode material is successfully prepared through a simple chemical vapor deposition (CVD) method. According to the transmission electron microscope (TEM) analysis, the surface of the LiFePO4/C is surrounded with PPy in the LiFePO4/C-PPy composite. The as-prepared LiFePO4/C-PPy material shows outstanding rate capability at 20°C and good cycle performance at 55°C in comparison with those of the bare LiFePO4/C material against Li anode. After 700 cycles, the discharge capacity of LiFePO4/C-PPy could still remain 110 mA h g−1 with …


Preparation, Characterization, And Electrochemical Performance Of Li2cusno4 And Li2cusnsio6 Electrodes For Lithium Batteries, Atef Y. Shenouda, Hua-Kun Liu Jan 2010

Preparation, Characterization, And Electrochemical Performance Of Li2cusno4 And Li2cusnsio6 Electrodes For Lithium Batteries, Atef Y. Shenouda, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Lithium copper tin silicon oxide was prepared from their precursor compounds using Brij surfactant and different sources of Si such as SiO2, SiC, and Si3N4. A hydrothermal autoclave method was used in the first stage of the preparation. X-ray diffraction characterization revealed that the crystal structures of these compounds were tetragonal. Scanning electron microscope investigation showed that the particle size morphology of Li2CuSnSiO6 is larger than that of Li2CuSnO4. Electrochemical impedance spectroscopy explained that the cell prepared from the Li2CuSnSiO6 electrode using Si3 …