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Full-Text Articles in Physical Sciences and Mathematics

Enhanced X-Ray Imaging For A Thin Film Cochlear Implant With Metal Artefacts Using Phase Retrieval Tomography, B D. Arhatari, Alexander R. Harris, Antonio G. Paolini, Andrew G. Peele Jan 2012

Enhanced X-Ray Imaging For A Thin Film Cochlear Implant With Metal Artefacts Using Phase Retrieval Tomography, B D. Arhatari, Alexander R. Harris, Antonio G. Paolini, Andrew G. Peele

Australian Institute for Innovative Materials - Papers

Phase retrieval tomography has been successfully used to enhance imaging in systems that exhibit poor absorption contrast. However, when highly absorbing regions are present in a sample, so-called metal artefacts can appear in the tomographic reconstruction. We demonstrate that straightforward approaches for metal artefact reconstruction, developed in absorption contrast tomography, can be applied when using phase retrieval. Using a prototype thin film cochlear implant that has high and low absorption components made from iridium (or platinum) and plastic, respectively, we show that segmentation of the various components is possible and hence measurement of the electrode geometry and relative location to …


One-Pot Synthesis Of Colloidal Silicon Quantum Dots And Surface Functionalization Via Thiol-Ene Click Chemistry, Xiaoyu Cheng, Richard Gondosiswanto, Simone Ciampi, Peter J. Reece, J Justin Gooding Jan 2012

One-Pot Synthesis Of Colloidal Silicon Quantum Dots And Surface Functionalization Via Thiol-Ene Click Chemistry, Xiaoyu Cheng, Richard Gondosiswanto, Simone Ciampi, Peter J. Reece, J Justin Gooding

Australian Institute for Innovative Materials - Papers

A solution method for preparing surface functionalized colloidal silicon quantum dots (SiQDs) is presented. SiQDs prepared by this method are reasonably monodispersed and can be further functionalized via thiol-ene click reactions to introduce specific functionalities (i.e. -NH2, -COOH, -SO 3 -, alkane, alkene).


Anti And Gauche Conformers Of An Inorganic Butane Analogue, Nh3bh2nh2bh3, Xuenian Chen, Judith C. Gallucci, Charles Campana, Zhenguo Huang, Hima Kumar Lingam, Sheldon G. Shore, Ji-Cheng Zhao Jan 2012

Anti And Gauche Conformers Of An Inorganic Butane Analogue, Nh3bh2nh2bh3, Xuenian Chen, Judith C. Gallucci, Charles Campana, Zhenguo Huang, Hima Kumar Lingam, Sheldon G. Shore, Ji-Cheng Zhao

Australian Institute for Innovative Materials - Papers

The crystal structures of an inorganic butane analogue, NH3BH2NH2BH3 (DDAB), were determined using single crystal X-ray diffraction, revealing both anti and gauche conformations. The anti conformation is stabilized by intermolecular dihydrogen bonds in the crystal whereas two gauche conformations of DDAB observed in its 18-crown-6 adducts are stabilized by an intramolecular dihydrogen bond. The two gauche conformations show rotational isomerization but whether they are a pair of enantiomers is yet to be defined.


Kfe2se2 Is The Parent Compound Of K-Doped Iron Selenide Superconductors, Weijie Li, Hao Ding, Zhi Li, Peng Deng, Kai Chang, Ke He, Shuaihua Ji, Lili Wang, Xu-Cun Ma, Jiang-Ping Hu, Xi Chen, Qi-Kun Xue Jan 2012

Kfe2se2 Is The Parent Compound Of K-Doped Iron Selenide Superconductors, Weijie Li, Hao Ding, Zhi Li, Peng Deng, Kai Chang, Ke He, Shuaihua Ji, Lili Wang, Xu-Cun Ma, Jiang-Ping Hu, Xi Chen, Qi-Kun Xue

Australian Institute for Innovative Materials - Papers

We elucidate the existing controversies in the newly discovered K-doped iron selenide (KxFe2ySe2z) superconductors. The stoichiometric KFe2Se2 with ffiffiffi 2 p ffiffiffi 2 p charge ordering was identified as the parent compound of KxFe2ySe2z superconductor using scanning tunneling microscopy and spectroscopy. The superconductivity is induced in KFe2Se2 by either Se vacancies or interacting with the antiferromagnetic K2Fe4Se5 compound. In total, four phases were found to exist in KxFe2ySe2z: parent compound KFe2Se2, superconducting KFe2Se2 with ffiffiffi 2 p ffiffiffi 5 p charge ordering, superconducting KFe2Se2z with Se vacancies, and insulating K2Fe4Se5 with ffiffiffi 5 p ffiffiffi 5 p Fe vacancy order. …


An Efficient Way To Enhance Output Strain For Shear Mode Pb(In1/2nb1/2)O-3-Pb(Mg1/3nb2/3)O-3-Pbtio3 Crystals: Applying Uniaxial Stress Perpendicular To Polar Direction, Fei Li, Shujun Zhang, Zhuo Xu, Dabin Lin, Junjie Gao, Zhenrong Li, Linghang Wang Jan 2012

An Efficient Way To Enhance Output Strain For Shear Mode Pb(In1/2nb1/2)O-3-Pb(Mg1/3nb2/3)O-3-Pbtio3 Crystals: Applying Uniaxial Stress Perpendicular To Polar Direction, Fei Li, Shujun Zhang, Zhuo Xu, Dabin Lin, Junjie Gao, Zhenrong Li, Linghang Wang

Australian Institute for Innovative Materials - Papers

The shear piezoelectric behavior of [001] poled tetragonal and [011] poled rhombohedral Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) crystals, with "1T" and "2R" domain configurations, respectively, were investigated under uniaxial stress perpendicular to polar direction. The shear piezoelectric coefficient d15 was found to decrease with increasing compressive stress for both "1T" and "2R" crystals. Based on thermodynamic analysis, the phase structure can be stabilized by applying compressive stress perpendicular to polar direction, resulting in a "harder" polarization rotation process, accounts for the reduced shear piezoelectric coefficient. Of particular importance is that the allowable drive electric field was greatly increased and transverse dielectric loss was …


High Performance Ferroelectric Relaxor-Pbtio3 Single Crystals: Status And Perspective, Shujun Zhang, Fei Li Jan 2012

High Performance Ferroelectric Relaxor-Pbtio3 Single Crystals: Status And Perspective, Shujun Zhang, Fei Li

Australian Institute for Innovative Materials - Papers

Ferroelectrics are essential components in a wide range of applications, including ultrasonic transducers, sensors, and actuators. In the single crystal form, relaxor-PbTiO3 (PT) piezoelectric materials have been extensively studied due to their ultrahigh piezoelectric and electromechanical properties. In this article, a perspective and future development of relaxor-PT crystals are given. Initially, various techniques for the growth of relaxor-PT crystals are reviewed, with crystals up to 100 mm in diameter and 200 mm in length being readily achievable using the Bridgman technique. Second, the characterizations of dielectric and electromechanical properties are surveyed. Boundary conditions, including temperature, electric field, and stress, are …


Hollow Nitrogen Containing Core/Shell Fibrous Carbon Nanomaterials As Support To Platinum Nanocatalysts And Their Tem Tomography Study, Cuifeng Zhou, Zongwen Liu, Xusheng Du, David Rg Mitchell, Yiu-Wing Mai, Yushan Yan, Simon Peter Ringer Jan 2012

Hollow Nitrogen Containing Core/Shell Fibrous Carbon Nanomaterials As Support To Platinum Nanocatalysts And Their Tem Tomography Study, Cuifeng Zhou, Zongwen Liu, Xusheng Du, David Rg Mitchell, Yiu-Wing Mai, Yushan Yan, Simon Peter Ringer

Australian Institute for Innovative Materials - Papers

Core/shell nanostructured carbon materials with carbon nanofiber (CNF) as the core and a nitrogen (N)-doped graphitic layer as the shell were synthesized by pyrolysis of CNF/polyaniline (CNF/PANI) composites prepared by in situ polymerization of aniline on CNFs. High-resolution transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared and Raman analyses indicated that the PANI shell was carbonized at 900 degress C. Platinum (Pt) nanoparticles were reduced by formic acid with catalyst supports. Compared to the untreated CNF/ PANI composites, the carbonized composites were proven to be better supporting materials for the Pt nanocatalysts and showed superior performance as catalyst …


The Problem Of Road Congestion: The Fultility Of 'Avoidable Cost' Estimates, Mark D. Harrison Jan 2012

The Problem Of Road Congestion: The Fultility Of 'Avoidable Cost' Estimates, Mark D. Harrison

Australian Institute for Innovative Materials - Papers

The Bureau of Infrastructure, Transport and Regional Economics estimates of the costs of road congestion in Australian capital cities ($9.4 billion in 2005 and projected to more than double by 2020) are widely cited. But these projections appear to overstate the problem and provide little, if any, guidance for sound policy development. They are not measures of the net gain from introducing congestion charging. Moreover, such numbers provide no help for evaluating the net benefits of other policies to deal with congestion, such as increasing road capacity. Without efficiency-based cost-benefit analysis of all policies to deal with road congestion, governments …


Physicochemical Study Of Spiropyran-Terthiophene Derivatives: Photochemistry And Thermodynamics, Michele Zanoni, Simon Coleman, Kevin J. Fraser, Robert P. Byrne, Klaudia K. Wagner, Sanjeev Gambhir, David L. Officer, Gordon G. Wallace, D Diamond Jan 2012

Physicochemical Study Of Spiropyran-Terthiophene Derivatives: Photochemistry And Thermodynamics, Michele Zanoni, Simon Coleman, Kevin J. Fraser, Robert P. Byrne, Klaudia K. Wagner, Sanjeev Gambhir, David L. Officer, Gordon G. Wallace, D Diamond

Australian Institute for Innovative Materials - Papers

The photochemistry and thermodynamics of two terthiophene (TTh) derivatives bearing benzospiropyran (BSP) moieties, 1-(3,3''-dimethylindoline-6'-nitrobenzospiropyranyl)-2-ethyl 4,4''-didecyloxy-2,2':5',2''-terthiophene-30-acetate (BSP-2) and 1-(3,3''-dimethylindoline-6'- nitrobenzospiropyranyl)-2-ethyl 4,4''-didecyloxy-2,2':5',2''-terthiophene-30-carboxylate (BSP-3), differing only by a single methylene spacer unit, have been studied. The kinetics of photogeneration of the equivalent merocyanine (MC) isomers (MC-2 and MC-3, respectively), the isomerisation properties of MC-2 and MC-3, and the thermodynamic parameters have been studied in acetonitrile, and compared to the parent, non-TTh-functionalised, benzospiropyran derivative, BSP-1. Despite the close structural similarity of BSP-2 and BSP-3, their physicochemical properties were found to differ significantly; examples include activation energies (Ea(MC-2) = 75.05 kJ mol-1, …


Ferroelectric And Ferromagnetic Nanofibers: Synthesis, Properties And Applications, A Jalalian, A M. Grishin, S X. Dou Jan 2012

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

Australian Institute for Innovative Materials - Papers

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. …


Vapor Phase Polymerization Of Edot From Submicrometer Scale Oxidant Patterned By Dip-Pen Nanolithography, Cathal D. O'Connell, Michael J. Higgins, Hiroshi Nakashima, Simon E. Moulton, Gordon G. Wallace Jan 2012

Vapor Phase Polymerization Of Edot From Submicrometer Scale Oxidant Patterned By Dip-Pen Nanolithography, Cathal D. O'Connell, Michael J. Higgins, Hiroshi Nakashima, Simon E. Moulton, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Some of the most exciting recent advances in conducting polymer synthesis have centered around the method of vapor phase polymerization (VPP) of thin films. However, it is not known whether the VPP process can proceed using significantly reduced volumes of oxidant and therefore be implemented as part of nanolithography approach. Here, we present a strategy for submicrometer scale patterning of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) via in situ VPP. Attolitre (10-18 L) volumes of oxidant "ink" are controllably deposited using dip-pen nanolithography (DPN). DPN patterning of the oxidant ink is facilitated by the incorporation of an amphiphilic block copolymer …


K0.25mn2o4 Nanofiber Microclusters As High Power Cathode Materials For Rechargeable Lithium Batteries, Chaofeng Zhang, Chuanqi Feng, Peng Zhang, Zaiping Guo, Zhixin Chen, Sean Li, Hua-Kun Liu Jan 2012

K0.25mn2o4 Nanofiber Microclusters As High Power Cathode Materials For Rechargeable Lithium Batteries, Chaofeng Zhang, Chuanqi Feng, Peng Zhang, Zaiping Guo, Zhixin Chen, Sean Li, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

K0.25Mn2O4 microclusters assembled from single-crystalline nanofibers were synthesized via a hydrothermal process at different temperatures. The possibility of using these materials as cathode material for lithium ion batteries was studied for the first time. The charge/discharge results showed that the K0.25Mn2O4 nanofiber microclusters synthesized at 120 degrees C exhibit excellent lithium storage properties, with a high reversible capability (360 mA h g-1 at current density of 100 mA g-1) and stable lithium-ion insertion/de-insertion reversibility. The charge/discharge mechanism in lithium ion batteries was studied and proposed for the …


Why Do Girls Sustain More Anterior Cruciate Ligament Injuries Than Boys? A Review Of The Changes In Oestrogen And Musculoskeletal Structure And Function During Puberty, Catherine Y. Wild, Julie R. Steele, Bridget J. Munro Jan 2012

Why Do Girls Sustain More Anterior Cruciate Ligament Injuries Than Boys? A Review Of The Changes In Oestrogen And Musculoskeletal Structure And Function During Puberty, Catherine Y. Wild, Julie R. Steele, Bridget J. Munro

Australian Institute for Innovative Materials - Papers

Sport is the leading cause of injury among adolescents and girls incur more non-contact anterior cruciate ligament (ACL) ruptures than boys, with this gender disparity in injury incidence apparent from the onset of puberty. Although the mechanisms for this gender disparity in ACL injuries are relatively unknown, hormonal, anatomical and biomechanical factors have been implicated. Puberty is associated with rapid skeletal growth and hormonal influx, both of which are thought to contribute to alterations in ACL metabolic and mechanical properties, as well as changes in lower limb strength and flexibility, ultimately influencing landing technique. Therefore, the aim of this review …


Free-Standing Single-Walled Carbon Nanotube/Sno2 Anode Paper For Flexible Lithium-Ion Batteries, Lukman Noerochim, Jia-Zhao Wang, Shulei Chou, David Wexler Jan 2012

Free-Standing Single-Walled Carbon Nanotube/Sno2 Anode Paper For Flexible Lithium-Ion Batteries, Lukman Noerochim, Jia-Zhao Wang, Shulei Chou, David Wexler

Australian Institute for Innovative Materials - Papers

Free-standingsingle-walledcarbonnanotube/SnO2 (SWCNT/SnO2) anodepaper was prepared by vacuum filtration of SWCNT/SnO2 hybrid material which was synthesized by the polyol method. From field emission scanning electron microscopy and transmission electron microscopy, the CNTs form a three-dimensional nanoporous network, in which ultra-fine SnO2 nanoparticles, which had crystallite sizes of less than 5 nm, were distributed, predominately as groups of nanoparticles on the surfaces of singlewalled CNT bundles. Electrochemical measurements demonstrated that the anodepaper with 34 wt.% SnO2 had excellent cyclic retention, with the high specific capacity of 454 mAh g−1 beyond 100 cycles at a current …


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 …


Quasi-One-Dimensional Intermittent Flux Behavior In Superconducting Films, A J. Qviller, V V. Yurchenko, Y M. Galperin, J I. Vestgarden, P B. Mozhaeva, J B. Hansen, T H. Johansen Jan 2012

Quasi-One-Dimensional Intermittent Flux Behavior In Superconducting Films, A J. Qviller, V V. Yurchenko, Y M. Galperin, J I. Vestgarden, P B. Mozhaeva, J B. Hansen, T H. Johansen

Australian Institute for Innovative Materials - Papers

Intermittent filamentary dynamics of the vortex matter in superconductors is found in films of YBa2Cu3O7-δ deposited on tilted substrates. Deposition of this material on such substrates creates parallel channels of easy flux penetration when a magnetic field is applied perpendicular to the film. As the applied field is gradually increased, magneto-optical imaging reveals that flux penetrates via numerous quasi-one-dimensional jumps. The distribution of flux avalanche sizes follows a power law, and data collapse is obtained by finite-size scaling, with the depth of the flux front used as crossover length. The intermittent behavior shows no threshold …


Isomorphism In Two (E)-1-(4-Halophenyl)-N-[1-(4-Methylphenyl)-1h-Imidazol-4-Yl]Methanimines (Halide = Cl, Br), Hanna Skrzypiec, Radoslaw Mazurek, Pawel Wagner, Maciej Kubicki Jan 2012

Isomorphism In Two (E)-1-(4-Halophenyl)-N-[1-(4-Methylphenyl)-1h-Imidazol-4-Yl]Methanimines (Halide = Cl, Br), Hanna Skrzypiec, Radoslaw Mazurek, Pawel Wagner, Maciej Kubicki

Australian Institute for Innovative Materials - Papers

The crystal structures of two imidazole-4-imines, (E)-1-(4-chlorophenyl)-N-[1-(4-methylphenyl)-1H-imidazol-4-yl]methanimine (1, C17H14ClN3), and (E)-1-(4-bromophenyl)-N-[1-(4-methylphenyl)-1H-imidazol-4-yl]methanimine, (2, C17H14BrN3), are isomorphous, the isostructurality index is 99.4 %. Both compounds crystallize in the triclinic space group P-1 with unit cell parameters at 100(1) K as follows: for (1), a = 7.9767(5) Å, b = 10.9517(7) Å, c = 16.6753(12) Å, α = 80.522(6)°, β = 87.046(6)°, γ = 89.207(5)°, and for (2), a = 8.0720(7) Å, b = 10.9334(10) Å, c = 16.8433(13) Å, α = 81.161(7)°, β = 86.605(7)°, γ = 89.505(7)°. The structures contain two symmetry—independent but conformationally similar molecules in the asymmetric unit (Z’ …


Methane Activation On Fe4 Cluster: A Density Functional Theory Study, Qiao Sun, Zhen Li, Meng Wang, Aijun Du, Sean C. Smith Jan 2012

Methane Activation On Fe4 Cluster: A Density Functional Theory Study, Qiao Sun, Zhen Li, Meng Wang, Aijun Du, Sean C. Smith

Australian Institute for Innovative Materials - Papers

We report a comprehensive theoretical study on reaction of methane by Fe4 cluster. This Letter gains insight into the mechanism of the reaction and indicate the Fe4 cluster has strong catalytic effect on the activation reaction of methane. In detail, the results show the cleavage of the first C-H bond is both an energetically and kinetically favourable process and the breaking of the second C-H is the rate-determining step. Moreover, our Letter demonstrates that the different cluster size of iron can not only determine the catalytic activity of methane but also control the product selectivity.


Improved Photovoltaic Performance Of Dye-Sensitized Solar Cells With Modified Self-Assembling Highly Ordered Mesoporous Tio2 Photoanodes, Ziqi Sun, Jung Ho Kim, Yue Zhao, Fargol Bijarbooneh, Victor Malgras, S X. Dou Jan 2012

Improved Photovoltaic Performance Of Dye-Sensitized Solar Cells With Modified Self-Assembling Highly Ordered Mesoporous Tio2 Photoanodes, Ziqi Sun, Jung Ho Kim, Yue Zhao, Fargol Bijarbooneh, Victor Malgras, S X. Dou

Australian Institute for Innovative Materials - Papers

Strategies for improving the photovoltaic performance of dye-sensitized solar cells (DSSCs) are proposed by modifying highly transparent and highly ordered multilayer mesoporous TiO2 photoanodes through nitrogen-doping and top-coating with a light-scattering layer. The mesoporous TiO2 photoanodes were fabricated by an evaporation-induced self-assembly method. In regard to the modification methods, the light-scattering layer as a top-coating was proved to be superior to nitrogen-doping in enhancing not only the power conversion efficiency but also the fill factor of DSSCs. The optimized bifunctional photoanode consisted of a 30-layer mesoporous TiO2 thin film (4.15 mm) and a Degussa P25 light-scattering top-layer (4 mm), which …


Investigation Of The Hydrogen Storage Mechanism Of Expanded Graphite By Measuring Electrical Resistance Changes, Ji Sun Im, Seungsoon Jang, Youngseak Lee Jan 2012

Investigation Of The Hydrogen Storage Mechanism Of Expanded Graphite By Measuring Electrical Resistance Changes, Ji Sun Im, Seungsoon Jang, Youngseak Lee

Australian Institute for Innovative Materials - Papers

The hydrogen storage mechanism of graphite was studied by measuring the electrical resistance change. Graphite was expanded and activated to allow for an easy hydrogen molecule approach and to enlarge the adsorption sites. A vanadium catalyst was simultaneously introduced on the graphite during the activation process. The hydrogen storage increased due to the effects of expansion, activation, and the catalyst. In addition, the electrical resistance of the prepared samples was measured during hydrogen molecule adsorption to investigate the hydrogen adsorption mechanism. It was found that the electrical resistance changed as a result of the easy hydrogen molecule approach, as well …


Effects Of Atomic Layer Deposited Thin Films On Dye Sensitized Solar Cell Performance, Jonathan A. Campbell, Mervyn Deborniol, Attila J. Mozer, Peter J. Evans, Robert P. Burford, Gerry Triani Jan 2012

Effects Of Atomic Layer Deposited Thin Films On Dye Sensitized Solar Cell Performance, Jonathan A. Campbell, Mervyn Deborniol, Attila J. Mozer, Peter J. Evans, Robert P. Burford, Gerry Triani

Australian Institute for Innovative Materials - Papers

"The application of thin titania films by atomic layer deposition on top of a low temperature nanoparticulate TiO2 electrode was found to enhance the performance of dye sensitized solar cells. Dynamic measurements of photoinduced charge extraction showed that the atomic layer deposited top coat increased the electron lifetime at the same electron density. This was attributed to an increased electron trap concentration, which resulted in slower charge transport and increased charge carrier lifetimes.


Flux Pinning And Vortex Transitions In Doped Bafe2as2 Single Crystals, S R. Ghorbani, X L. Wang, M Shabazi, S X. Dou, K Y. Choi, C T. Lin Jan 2012

Flux Pinning And Vortex Transitions In Doped Bafe2as2 Single Crystals, S R. Ghorbani, X L. Wang, M Shabazi, S X. Dou, K Y. Choi, C T. Lin

Australian Institute for Innovative Materials - Papers

The vortex liquid-to-glass transition has been studied in Ba0.72K0.28Fe2As2 (BaK-122), Ba(Fe0.91Co0.09)2As2(BaCo-122), and Ba(Fe0.95Ni0.05)2As2(BaNi-122) single crystal with superconducting transition temperature, Tc=31.7, 17.3, and 18 K, respectively, by magnetoresistance measurements. For temperatures below Tc, the resistivity curves were measured in magnetic fields within the range of 0≤B≤13 T, and the pinning potential was scaled according to a modified model for vortex liquid resistivity. Good scaling of the resistivity q(B, T) and the effective pinning energy …


Flux Distribution In Fe-Based Superconducting Materials By Magneto-Optical Imaging, Zhi Wei Lin, Jian Guo Zhu, You Guang Guo, Xiaolin Wang, S X. Dou, Tom H. Johansen, Xun Shi, K Y. Choi Jan 2012

Flux Distribution In Fe-Based Superconducting Materials By Magneto-Optical Imaging, Zhi Wei Lin, Jian Guo Zhu, You Guang Guo, Xiaolin Wang, S X. Dou, Tom H. Johansen, Xun Shi, K Y. Choi

Australian Institute for Innovative Materials - Papers

"This paper presents the magnetic flux distributions in Fe-based superconducting materials including single crystal of Ba(Fe1.9Ni0.1)As2 and Ba(Fe1.8Co0.2)As2, as well as polycrystalline SmFeO0.75F0.2As by means of magneto-optical imaging (MOI) technique. The single crystals were grown out of FeAs flux while polycrystalline sample was grown by hot-press. A MOI film with in-plan magnetization was used to visualize flux distributions at the sample surface. A series of magneto-optical images was taken when the samples were zero-field cooled and field cooled. The flux behavior, including penetration into and …


All-Polymer Battery System Based On Polypyrrole (Ppy)/Para (Toluene Sulfonic Acid) (Pts) And Polypyrrole (Ppy)/Indigo Carmine (Ic) Free Standing Films, Irin Sultana, Md. Mokhlesur Rahman, Jiazhao Wang, Caiyun Wang, Gordon G. Wallace, Hua-Kun Liu Jan 2012

All-Polymer Battery System Based On Polypyrrole (Ppy)/Para (Toluene Sulfonic Acid) (Pts) And Polypyrrole (Ppy)/Indigo Carmine (Ic) Free Standing Films, Irin Sultana, Md. Mokhlesur Rahman, Jiazhao Wang, Caiyun Wang, Gordon G. Wallace, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

In this study, we introduce a novel all-polymer battery system based on conducting polymer (polypyrrole, PPy) doped with dopants of para (toluene sulfonic acid) (pTS) and indigo carmine (IC), respectively. The performance of the systems consisting of polypyrrole-para (toluene sulfonic acid) (PPy-pTS) as cathode and polypyrrole-indigo carmine (PPy-IC) as anode in conjunction with either a polymer based electrolyte or a commercial organic electrolyte of 1M LiPF6 in a 50:50 (v/v) mixture of ethylene carbonate (EC) and dimethyl carbonate (DMC) was evaluated. In the system, all the free-standing PPy-pTS and PPy-IC films were directly …


Lifepo4-Fe2p-C Composite Cathode: An Environmentally Friendly Promising Electrode Material For Lithium-Ion Battery, M. Mahfuzur Rahman, Jiazhao Wang, Rong Zeng, David Wexler, Hua-Kun Liu Jan 2012

Lifepo4-Fe2p-C Composite Cathode: An Environmentally Friendly Promising Electrode Material For Lithium-Ion Battery, M. Mahfuzur Rahman, Jiazhao Wang, Rong Zeng, David Wexler, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

In this investigation, the synthesis strategy is involved the creation of LiFePO4-Fe2P-C composites with a porous conductive architecture, which includes distinct regions or clusters containing antiferromagnetic LiFePO4 in close proximity to ferromagnetic Fe2P. The microstructure is achieved by using a simple ultra-fast solvent assisted manual grinding method, combined with solid state reaction, which can replace the time-consuming high energy ball milling method. The crystalline structure, morphology, and electrochemical characterization of the synthesised product are investigated systematically. The electrochemical performance is outstanding, especially the high C rate. The composite cathode is found to display specific capacity of 167 mAh g-1 at …


Magnetic And Superconducting Properties Of Spin-Fluctuation-Limited Superconducting Nanoscale Vnx, R Zeng, J Liu, G Du, W. X. Li, J Wang, J Horvat, S X. Dou Jan 2012

Magnetic And Superconducting Properties Of Spin-Fluctuation-Limited Superconducting Nanoscale Vnx, R Zeng, J Liu, G Du, W. X. Li, J Wang, J Horvat, S X. Dou

Australian Institute for Innovative Materials - Papers

"VNx nanoparticles and nanowires have been prepared by nitrifying V2O5 nanoparticles (NP) and nanowires (NW). The V2O5 NP and NW were synthesized by a facile hydrothermal method. Magnetic susceptibility (chi) and magnetization measurements showed long range superconducting ordering (LRSO) at the temperature of 5.8 K for NW, but there was no observation of LRSO (at least down to 2 K) for the NP sample, which is a much lower temperature than for the corresponding bulk, while both NP and NW showed the absence of long range magnetic ordering, at least down to 2 K. However, the chi data showed that …


Irradiation Si On Carbon Nanotube Paper As A Flexible Anode Material For Lithium-Ion Batteries, Shulei Chou, Mihail Ionescu, Jia-Zhao Wang, Brad Winton, Hua-Kun Liu Jan 2012

Irradiation Si On Carbon Nanotube Paper As A Flexible Anode Material For Lithium-Ion Batteries, Shulei Chou, Mihail Ionescu, Jia-Zhao Wang, Brad Winton, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Silicon single walled carbon nanotube composite paper was modified by low energy ion implantation using 5i to obtain a flexible composite paper. Raman and FE-SEM results show that structure of SWCNT could be destroyed by the implantation. Electrochemical measurements display that the implanted SI can improve the specific capacity and the reversible capacity of CNT paper. After 50 cycles, the specific capacity of 5Hmplanted CNT paper is 30 per cent higher than the pristine CNT.


Lightning In Superconductors, J I. Vestgarden, D.V Shantsev, Y M. Galperin, T H. Johansen Jan 2012

Lightning In Superconductors, J I. Vestgarden, D.V Shantsev, Y M. Galperin, T H. Johansen

Australian Institute for Innovative Materials - Papers

Crucially important for application of type-II superconductor films is the stability of the vortex matter-magnetic flux lines penetrating the material. If some vortices get detached from pinning centres, the energy dissipated by their motion will facilitate further depinning, and may trigger a massive electromagnetic breakdown. Up to now, the time-resolved behaviour of these ultra-fast events was essentially unknown. We report numerical simulation results revealing the detailed dynamics during breakdown as within nanoseconds it develops branching structures in the electromagnetic fields and temperature, with striking resemblance of atmospheric lightning. During a dendritic avalanche the superconductor is locally heated above its critical …


Approximate Techniques For Dispersive Shock Waves In Nonlinear Media, Timothy R. Marchant, Noel F. Smyth Jan 2012

Approximate Techniques For Dispersive Shock Waves In Nonlinear Media, Timothy R. Marchant, Noel F. Smyth

Australian Institute for Innovative Materials - Papers

Many optical and other nonlinear media are governed by dispersive, or diffractive, wave equations, for which initial jump discontinuities are resolved into a dispersive shock wave. The dispersive shock wave smooths the initial discontinuity and is a modulated wavetrain consisting of solitary waves at its leading edge and linear waves at its trailing edge. For integrable equations the dispersive shock wave solution can be found using Whitham modulation theory. For nonlinear wave equations which are hyperbolic outside the dispersive shock region, the amplitudes of the solitary waves at the leading edge and the linear waves at the trailing edge of …


Microporous Gel Polymer Electrolytes For Lithium Rechargeable Battery Application, Nurul Hayati Idris, Md. Mokhlesur Rahman, Jia-Zhao Wang, Hua-Kun Liu Jan 2012

Microporous Gel Polymer Electrolytes For Lithium Rechargeable Battery Application, Nurul Hayati Idris, Md. Mokhlesur Rahman, Jia-Zhao Wang, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Microporous poly(vinylidene fluoride)/poly(methyl methacrylate) (PVDF/PMMA) membranes were prepared using the phase-separation method. Then, the membranes were immersed in liquid electrolyte to form polymer electrolytes. The effects of PMMA on the morphology, degree of crystallinity, porosity, and electrolyte uptake of the PVDF membrane were studied. The addition of PMMA increased the pore size, porosity and electrolyte uptake of the PVDF membrane, which in turn increased the ionic conductivity of the polymer electrolyte. The maximum ionic conductivity at room temperature was 1.21 × 10−3 S cm−1 for Sample E70. The polymer electrolyte was investigated, along with lithium iron phosphate (LiFePO4) as cathode …