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Articles 147061 - 147090 of 302639

Full-Text Articles in Physical Sciences and Mathematics

Fish-Scale Bio-Inspired Multifunctional Zno Nanostructures, Ziqi Sun, Ting Liao, W Li, Yuhai Dou, Kesong Liu, Lei Jiang, Sang Woo Kim, Jung Ho Kim, S X. Dou Jan 2015

Fish-Scale Bio-Inspired Multifunctional Zno Nanostructures, Ziqi Sun, Ting Liao, W Li, Yuhai Dou, Kesong Liu, Lei Jiang, Sang Woo Kim, Jung Ho Kim, S X. Dou

Australian Institute for Innovative Materials - Papers

Scales provide optical disguise, low water drag and mechanical protection to fish, enabling them to survive catastrophic environmental disasters, predators and microorganisms. The unique structures and stacking sequences of fish scales inspired the fabrication of artificial nanostructures with salient optical, interfacial and mechanical properties. Herein, we describe fish-scale bio-inspired multifunctional ZnO nanostructures that have similar morphology and structure to the cycloid scales of the Asian Arowana. These nanostructured coatings feature tunable light refraction and reflection, modulated surface wettability and damage-tolerant mechanical properties. The salient properties of these multifunctional nanostructures are promising for applications in (i) optical coatings, sensing or lens …

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Synthesis Of Large And Few Atomic Layers Of Hexagonal Boron Nitride On Melted Copper, Majharu Haque Khan, Zhenguo Huang, Feng Xiao, Gilberto Casillas, Zhixin Chen, Paul Molino, Hua-Kun Liu Jan 2015

Synthesis Of Large And Few Atomic Layers Of Hexagonal Boron Nitride On Melted Copper, Majharu Haque Khan, Zhenguo Huang, Feng Xiao, Gilberto Casillas, Zhixin Chen, Paul Molino, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Hexagonal boron nitride nanosheets (h-BNNS) have been proposed as an ideal substrate for graphene-based electronic devices, but the synthesis of large and homogeneous h-BNNS is still challenging. In this contribution, we report a facile synthesis of few-layer h-BNNS on melted copper via an atmospheric pressure chemical vapor deposition process. Comparative studies confirm the advantage of using melted copper over solid copper as a catalyst substrate. The former leads to the formation of single crystalline h-BNNS that is several microns in size and mostly in mono- and bi-layer forms, in contrast to the polycrystalline and mixed multiple layers (1-10) yielded by …

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Origin Of Resistivity Anomaly In P-Type Leads Chalcogenide Multiphase Compounds, Sima Aminorroaya-Yamini, David R. G Mitchell, Heng Wang, Zachary M. Gibbs, Yanzhong Pei, S X. Dou, G. Jeffrey Snyder Jan 2015

Origin Of Resistivity Anomaly In P-Type Leads Chalcogenide Multiphase Compounds, Sima Aminorroaya-Yamini, David R. G Mitchell, Heng Wang, Zachary M. Gibbs, Yanzhong Pei, S X. Dou, G. Jeffrey Snyder

Australian Institute for Innovative Materials - Papers

The electrical resistivity curves for binary phase compounds of p-type lead chalcogenide (PbTe)(0.9−x) (PbSe) 0.1 (PbS) x, (x = 0.15, 0.2, 0.25), which contain PbS-rich secondary phases, show different behaviour on heating and cooling between 500-700 K. This is contrast to single phase compounds which exhibit similar behaviour on heating and cooling. We correlate these anomalies in the electrical resistivities of multiphase compounds to the variation in phase composition at high temperatures. The inhomogeneous distribution of dopants between the matrix and secondary phase is found to be crucial in the electronic transport properties of the multiphase compounds. …

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Peptide Modification Of Purified Gellan Gum, Cameron Ferris, Leo Stevens, Kerry J. Gilmore, E Mume, Ivan Greguric, Damian Kirchmajer, Gordon G. Wallace, Marc In Het Panhuis Jan 2015

Peptide Modification Of Purified Gellan Gum, Cameron Ferris, Leo Stevens, Kerry J. Gilmore, E Mume, Ivan Greguric, Damian Kirchmajer, Gordon G. Wallace, Marc In Het Panhuis

Australian Institute for Innovative Materials - Papers

Gellan gum (GG) is an anionic polysaccharide with potential as a biopolymer for additive manufacturing (3D-bioprinting) and tissue engineering. Previous studies have shown GG to be highly cytocompatible, but lacking specific attachment sites required for anchorage-dependent cells. In this work, we modify purified-GG polymer with a short peptide containing the arginine-glycine-aspartic acid (RGD) sequence that is known to enhance integrin-mediated cell attachment. Radiolabelling of the peptide was used in optimisation of the conjugation procedure to achieve an overall efficiency of 40%. The purification of divalent cations from commercial GG samples was found to be critical for successful conjugation. Rheological studies …

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Nano-Carbon Electrodes For Thermal Energy Harvesting, Mark S. Romano, Joselito M. Razal, Dennis Antiohos, Gordon G. Wallace, Jun Chen Jan 2015

Nano-Carbon Electrodes For Thermal Energy Harvesting, Mark S. Romano, Joselito M. Razal, Dennis Antiohos, Gordon G. Wallace, Jun Chen

Australian Institute for Innovative Materials - Papers

Thermogalvanic cells are capable of converting waste heat (generated as a by-product of almost all human activity) to electricity. These devices may alleviate the problems associated with the use of fossil fuels to meet the world's current demand for energy. This review discusses the developments in thermogalvanic systems attained through the use of nano-carbons as the electrode materials. Advances in cell design and electrode configuration that improve performance of these thermo converters and make them applicable in a variety of environments are also summarized. It is the aim of this review to act as a channel for further developments in …

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Hierarchically Porous Carbon-Zirconium Carbide Spheres As Potentially Reusable Transmutation Targets, Nicholas Scales, Jun Chen, Tracey L. Hanley, Daniel P. Riley, Gregory R. Lumpkin, Vittorio Luca Jan 2015

Hierarchically Porous Carbon-Zirconium Carbide Spheres As Potentially Reusable Transmutation Targets, Nicholas Scales, Jun Chen, Tracey L. Hanley, Daniel P. Riley, Gregory R. Lumpkin, Vittorio Luca

Australian Institute for Innovative Materials - Papers

The preparation of hierarchically porous phase-pure carbon-zirconium carbide spheres with surface areas upwards of 70 m2/g and diameters in the 1-2 mm range has been achieved. The zirconium carbide beads were prepared through carbothermal reduction of polyacrylonitrile-zirconium composites prepared via three different routes including infiltration of a zirconium precursor into preformed polyacrylonitrile (PAN) beads and two one-pot co-precipitation methods. Depending on the route used to prepare the composites, relatively high surface area phase-pure zirconium carbides with the radial macroporous internal structure of the PAN template could be prepared. The adsorption of the elements U, Mo, Cs and Sr …

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Nano-Bioelectronics Via Dip-Pen Nanolithography, Cathal O'Connell, Michael J. Higgins, Simon E. Moulton, Gordon G. Wallace Jan 2015

Nano-Bioelectronics Via Dip-Pen Nanolithography, Cathal O'Connell, Michael J. Higgins, Simon E. Moulton, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

The emerging field of nano-biology is borne from advances in our ability to control the structure of materials on finer and finer length-scales, coupled with an increased appreciation of the sensitivity of living cells to nanoscale topographical, chemical and mechanical cues. As we envisage and prototype nanostructured bioelectronic devices there is a crucial need to understand how cells feel and respond to nanoscale materials, particularly as material properties (surface energy, conductivity etc.) can be very different at the nanoscale than at the bulk. However, the patterning of organic bioelectronic materials is often not achievable using conventional fabrication techniques, especially on …

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Semimetal-Semiconductor Transition And Giant Linear Magnetoresistances In Three-Dimensional Dirac Semimetal Bi0.96sb0.04 Single Crystals, Zengji Yue, Xiaolin Wang, Shi-Shen Yan Jan 2015

Semimetal-Semiconductor Transition And Giant Linear Magnetoresistances In Three-Dimensional Dirac Semimetal Bi0.96sb0.04 Single Crystals, Zengji Yue, Xiaolin Wang, Shi-Shen Yan

Australian Institute for Innovative Materials - Papers

Three-dimensional (3D) Dirac semimetals are new quantum materials and can be viewed as 3D analogues of graphene. Many fascinating electronic properties have been proposed and realized in 3D Dirac semimetals, which demonstrate their potential applications in next generation quantum devices. Bismuth-antimony Bi1− x Sb x can be tuned from a topological insulator to a band insulator through a quantum critical point at x ≈ 4%, where 3D Dirac fermions appear. Here, we report on a magnetotransport study of Bi1− x Sb x at such a quantum critical point. An unusual magnetic-field induced semimetal-semiconductor phase transition was observed in the Bi0.96Sb0.04 …

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The Effect Of Symmetry On Resonant And Nonresonant Photoresponses In A Field-Effect Terahertz Detector, J D. Sun, H Qin, Roger A. Lewis, Xiaoyu Yang, Y F. Sun, Zhenpu Zhang, Xianghu Li, Xiaoqin Zhang, Y Cai, D M. Wu, B S. Zhang Jan 2015

The Effect Of Symmetry On Resonant And Nonresonant Photoresponses In A Field-Effect Terahertz Detector, J D. Sun, H Qin, Roger A. Lewis, Xiaoyu Yang, Y F. Sun, Zhenpu Zhang, Xianghu Li, Xiaoqin Zhang, Y Cai, D M. Wu, B S. Zhang

Australian Institute for Innovative Materials - Papers

The effect of the symmetries in the terahertz (THz) field distribution and the field-effect channel on THz photoresponse is examined. Resonant excitation of cavity plasmon modes and nonresonant self-mixing of THz waves are demonstrated in a GaN/AlGaN two-dimensional electron gas with symmetrically designed nanogates, antennas, and filters. We found that the self-mixing signal can be effectively suppressed by the symmetric design and the resonant response benefits from the residual asymmetry. The findings suggest that a single detector may provide both high sensitivity from the self-mixing mechanism and spectral resolution from the resonant response by optimizing the degree of geometrical and/or …

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Hollow Carbon Spheres With Encapsulated Germanium As An Anode Material For Lithium Ion Batteries, Dan Li, Chuanqi Feng, Hua-Kun Liu, Zaiping Guo Jan 2015

Hollow Carbon Spheres With Encapsulated Germanium As An Anode Material For Lithium Ion Batteries, Dan Li, Chuanqi Feng, Hua-Kun Liu, Zaiping Guo

Australian Institute for Innovative Materials - Papers

A novel composite consisting of hollow carbon spheres with encapsulated germanium (Ge@HCS) was synthesized by introducing a germanium precursor into the porous-structured hollow carbon spheres. The carbon spheres not only function as a scaffold to hold the germanium and thus maintain the structural integrity of the composite, but also increase the electrical conductivity. The voids and vacancies that are formed after the reduction of germanium dioxide to germanium provide free space for accommodating the volume changes during discharging-charging processes, thus preventing pulverization. The obtained Ge@HCS composite exhibits excellent lithium storage performance, as revealed by electrochemical evaluation.

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Aqueous Preparation Of Surfactant-Free Copper Selenide Nanowires, Xinqi Chen, Zhen Li, Jianping Yang, Qiao Sun, S X. Dou Jan 2015

Aqueous Preparation Of Surfactant-Free Copper Selenide Nanowires, Xinqi Chen, Zhen Li, Jianping Yang, Qiao Sun, S X. Dou

Australian Institute for Innovative Materials - Papers

Uniform surfactant-free copper selenide (Cu2- x Se) nanowires were prepared via an aqueous route. The effects of reaction parameters such as Cu/Se precursor ratio, Se/NaOH ratio, and reaction time on the formation of nanowires were comprehensively investigated. The results show that Cu2- x Se nanowires were formed through the assembling of CuSe nanoplates, accompanied by their self-redox reactions. The resultant Cu2- x Se nanowires were explored as a potential thermoelectric candidate in comparison with commercial copper selenide powder. Both synthetic and commercial samples have a similar performance and their figures of merit are 0.29 and 0.38 at …

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One-Pot Synthesis Of Ultra-Small Magnetite Nanoparticles On The Surface Of Reduced Graphene Oxide Nanosheets As Anodes For Sodium-Ion Batteries, Shaohua Zhang, Weijie Li, Bien Tan, Shulei Chou, Zhen Li, S X. Dou Jan 2015

One-Pot Synthesis Of Ultra-Small Magnetite Nanoparticles On The Surface Of Reduced Graphene Oxide Nanosheets As Anodes For Sodium-Ion Batteries, Shaohua Zhang, Weijie Li, Bien Tan, Shulei Chou, Zhen Li, S X. Dou

Australian Institute for Innovative Materials - Papers

Nanocomposites with ultra-small magnetite (Fe3O4) nanoparticles (approx. 3 nm) uniformly anchored on the surfaces of reduced graphene oxide (RGO) nanosheets were successfully synthesized for anodes in sodium-ion batteries by a novel single-step high-temperature coprecipitation approach. The best electrode delivers a reversible Na+ storage capacity of 204 mA h g-1 with excellent capacity retention, i.e., 98% of the second-cycle value was retained after 200 cycles.

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Mgb2 Superconducting Joints For Persistent Current Operation, Dipakkumar Patel, Md S. Hossain, Khay Wai W. See, Xun Xu, Shaon Barua, Zongqing Ma, Seyong Choi, Mike Tomsic, Jung Ho Kim Jan 2015

Mgb2 Superconducting Joints For Persistent Current Operation, Dipakkumar Patel, Md S. Hossain, Khay Wai W. See, Xun Xu, Shaon Barua, Zongqing Ma, Seyong Choi, Mike Tomsic, Jung Ho Kim

Australian Institute for Innovative Materials - Papers

High-performance superconducting joints are essential for realizing persistent-mode magnets. Herein, we propose a concept and fabrication of such superconducting joints, which yielded reliable performance in the operating temperature range of 4.2-25 K. MgB2-MgB2 joints in magnets are known to result in deterioration of localized electrical, thermal, and mechanical properties. To overcome these problems, the ends of the two wires are inserted into a pellet press, which is then filled with a mixture of unreacted magnesium and boron powders, followed by heat treatment. The critical current capacity and joint resistance were precisely evaluated by the standard four-probe method …

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Guanidinium Octahydrotriborate: An Ionic Liquid With High Hydrogen Storage Capacity, Weidong Chen, Zhenguo Huang, Guotao Wu, Teng He, Zhao Li, Juner Chen, Zaiping Guo, Hua-Kun Liu, Ping Chen Jan 2015

Guanidinium Octahydrotriborate: An Ionic Liquid With High Hydrogen Storage Capacity, Weidong Chen, Zhenguo Huang, Guotao Wu, Teng He, Zhao Li, Juner Chen, Zaiping Guo, Hua-Kun Liu, Ping Chen

Australian Institute for Innovative Materials - Papers

For chemical hydrogen storage, capacity is one key criterion that has spurred intense efforts to investigate compounds with high hydrogen content. The guanidinium cation and the octahydrotriborate anion possess 6 H+ and 8 H-, respectively. The combination of these two ions yields guanidinium octahydrotriborate with 13.8 wt% hydrogen. This paper presents its facile synthesis, as confirmed by 11B and 1H nuclear magnetic resonance spectroscopy. The results show that guanidinium octahydrotriborate is an ionic liquid with a melting point below -10°C, which makes it a possible injectable/pumpable hydrogen carrier. It decomposes selectively to hydrogen, in stark …

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Influence Of Biopolymer Loading On The Physiochemical And Electrochemical Properties Of Inherently Conducting Polymer Biomaterials, Paul J. Molino, Peter C. Innis, Michael J. Higgins, Robert M. I Kapsa, Gordon G. Wallace Jan 2015

Influence Of Biopolymer Loading On The Physiochemical And Electrochemical Properties Of Inherently Conducting Polymer Biomaterials, Paul J. Molino, Peter C. Innis, Michael J. Higgins, Robert M. I Kapsa, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

The physicochemical and electrochemical properties of polypyrrole (PPy) doped with the biological dopant dextran sulphate (DS) were shown to be significantly altered as a function of varying the salt concentration (0.2, 2 or 20 mg/ml) in the polymerisation electrolyte. Films grown in the presence of 0.2 mg/ml DS generated the highest potential during galvanostatic growth, with the potential decreasing with each subsequent increase in DS concentration. The electroactivity of the polymers was similar for all three DS concentrations, with the 20 mg/ml film drawing slightly more current upon reduction in PBS. Increasing the DS concentration reduced film interfacial roughness and …

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Electrochemical Synthesis Of Mesoporous Pt Nanowires With Highly Electrocatalytic Activity Toward Methanol Oxidation Reaction, Cuiling Liu, Victor Malgras, Saad Alshehri, Jung Ho Kim, Yusuke Yamauchi Jan 2015

Electrochemical Synthesis Of Mesoporous Pt Nanowires With Highly Electrocatalytic Activity Toward Methanol Oxidation Reaction, Cuiling Liu, Victor Malgras, Saad Alshehri, Jung Ho Kim, Yusuke Yamauchi

Australian Institute for Innovative Materials - Papers

Self-supported one-dimensional (1D) mesoporous Pt nanowires (NWs) are prepared by confining micelle assembly in channels of a polycarbonate (PC) membrane. The obtained mesoporous Pt NWs show very high electrochemical activity and excellent durability as catalysts for methanol oxidation reaction (MOR) in comparison with the commercially available Pt black (PtB) catalyst. This work demonstrates that an appropriate combination of both self-supported 1D shape and mesoporous architecture indeed improve the electrocatalytic performances which is critical for further implementation and practical applications.

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A Class Of Rare Antiferromagnetic Metallic Oxides: Double Perovskite Amn(3)V(4)O(12) (A = Na+, Ca2+, And La3+) And The Site-Selective Doping Effect, Guangbiao Zhang, Yuan Xu Wang, Zhenxiang Cheng, Yuli Yan, Chengxiao Peng, Chao Wang, Shuai Dong Jan 2015

A Class Of Rare Antiferromagnetic Metallic Oxides: Double Perovskite Amn(3)V(4)O(12) (A = Na+, Ca2+, And La3+) And The Site-Selective Doping Effect, Guangbiao Zhang, Yuan Xu Wang, Zhenxiang Cheng, Yuli Yan, Chengxiao Peng, Chao Wang, Shuai Dong

Australian Institute for Innovative Materials - Papers

We have investigated the structural, electronic, and magnetic properties of A-site-ordered double-perovskitestructured oxides, AA'3B4O12 (A = Na, Ca, and La) with Mn and V at A' and B sites, respectively, using firstprinciple calculations based on the density functional theory. Our calculation results show that the antiferromagnetic phase is the ground state for all the compounds. By changing the A-site ions from Na+ to Ca2+ and then to La3+, the transfer of charge between Mn and O ions was changed from 1.56 to 1.55 and then to 1.50, and that between the …

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Tuneable Magnetic Phase Transitions In Layered Cemn2ge2-Xsix Compounds, M F. Md Din, Jianli Wang, Zhenxiang Cheng, S X. Dou, Shane J. Kennedy, Maxim Avdeev, Stewart J. Campbell Jan 2015

Tuneable Magnetic Phase Transitions In Layered Cemn2ge2-Xsix Compounds, M F. Md Din, Jianli Wang, Zhenxiang Cheng, S X. Dou, Shane J. Kennedy, Maxim Avdeev, Stewart J. Campbell

Australian Institute for Innovative Materials - Papers

The structural and magnetic properties of seven CeMn2Ge2-xSix compounds with x = 0.0-2.0 have been investigated in detail. Substitution of Ge with Si leads to a monotonic decrease of both a and c along with concomitant contraction of the unit cell volume and significant modifications of the magnetic states - a crossover from ferromagnetism at room temperature for Ge-rich compounds to antiferromagnetism for Si-rich compounds. The magnetic phase diagram has been constructed over the full range of CeMn2Ge2-xSix compositions and co-existence of ferromagnetism and antiferromagnetism has been observed in CeMn …

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Fabrication Of Thermoelectric Materials-Thermal Stability And Repeatability Of Achieved Efficiencies, Sima Aminorroaya-Yamini, Matthew D. Brewis, Jacob Byrnes, Rafael Santos, Andrew Manettas, Y Z. Pei Jan 2015

Fabrication Of Thermoelectric Materials-Thermal Stability And Repeatability Of Achieved Efficiencies, Sima Aminorroaya-Yamini, Matthew D. Brewis, Jacob Byrnes, Rafael Santos, Andrew Manettas, Y Z. Pei

Australian Institute for Innovative Materials - Papers

Metal chalcogenides have delivered the highest efficiencies among thermoelectric materials. Although the thermal stability of thermoelectric materials at device operating temperatures has been of concern, recent studies have reported the efficiencies of materials prepared with different fabrication techniques. Here, we have fabricated a p-type, multiphase lead chalcogenide compound of (PbTe)0.55(PbS)0.35(PbSe)0.1, with three common fabrication techniques of quenched, quenched-annealed and furnace cooled followed by spark plasma sintering. The compound contains PbS-rich precipitates within a PbTe-rich matrix. The achieved samples from various fabrication procedures demonstrate distinct microstructures that evolve with thermal cycling. We have shown that the thermoelectric efficiency of metastable compound …

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3d Braided Yarns To Create Electrochemical Cells, Chen Zhao, Syamak Farajikhah, Caiyun Wang, Javad Foroughi, Xiaoteng Jia, Gordon G. Wallace Jan 2015

3d Braided Yarns To Create Electrochemical Cells, Chen Zhao, Syamak Farajikhah, Caiyun Wang, Javad Foroughi, Xiaoteng Jia, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

The demands for new configurations of electrochemical cells continue to grow and novel approaches are being enabled by the advent of new electromaterials and novel fabrication strategies. Wearable energy storage devices that can be seamlessly integrated into garments are a critical component of the wearable electronics genre. Recently, flexible yarn supercapacitors have attracted significant attention due to their ability to be integrated into fabrics, or stitched into existing textiles. Large-scale production of yarn supercapacitors using conventional manufacturing processes, however, is still a challenge. Here, we introduce the use of braiding technology to achieve a predetermined arrangement of fibre electrodes, the …

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Three-Dimensional Controlled Growth Of Monodisperse Sub-50 Nm Heterogeneous Nanocrystals, Deming Liu, Xiaoxue Xu, Yi Du, Xian Qin, Yuhai Zhang, Chenshuo Ma, Shihui Wen, Wei Ren, Ewa M. Goldys, James A. Piper, S X. Dou, Xiaogang Liu, Dayong Jin Jan 2015

Three-Dimensional Controlled Growth Of Monodisperse Sub-50 Nm Heterogeneous Nanocrystals, Deming Liu, Xiaoxue Xu, Yi Du, Xian Qin, Yuhai Zhang, Chenshuo Ma, Shihui Wen, Wei Ren, Ewa M. Goldys, James A. Piper, S X. Dou, Xiaogang Liu, Dayong Jin

Australian Institute for Innovative Materials - Papers

The ultimate frontier in nanomaterials engineering is to realize their composition control with atomic scale precision to enable fabrication of nanoparticles with desirable size, shape and surface properties. Such control becomes even more useful when growing hybrid nanocrystals designed to integrate multiple functionalities. Here we report achieving such degree of control in a family of rare-earth-doped nanomaterials. We experimentally verify the co-existence and different roles of oleate anions (OA-) and molecules (OAH) in the crystal formation. We identify that the control over the ratio of OA- to OAH can be used to directionally inhibit, promote or etch the crystallographic facets …

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Conductive Surfaces With Dynamic Switching In Response To Temperature And Salt, Alissa Hackett, Jenny Malmström, Paul J. Molino, Julien Gautrot, Hongrui Zhang, Michael J. Higgins, Gordon G. Wallace, David E. Williams, Jadranka Travas-Sejdic Jan 2015

Conductive Surfaces With Dynamic Switching In Response To Temperature And Salt, Alissa Hackett, Jenny Malmström, Paul J. Molino, Julien Gautrot, Hongrui Zhang, Michael J. Higgins, Gordon G. Wallace, David E. Williams, Jadranka Travas-Sejdic

Australian Institute for Innovative Materials - Papers

This work demonstrates polymer brushes grafted from conductive polymer films which display dynamic surface switching dependent on salt, temperature and electrode potential. The electroactivity presented by the conductive polymer and the responsiveness of the grafted brushes leads to an interface with multiple control parameters. Here, we demonstrate this concept by grafting of uncharged brushes of poly(ethylene glycol)methyl ether methacrylates from conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT), and observe a temperature- and salt-induced switch of brush conformation, and their effect on the electrochemistry of the material. The switching conditions can be tailored by copolymerizing monomers with different numbers of ethylene glycol units. In …

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Hierarchical Heteroaggregation Of Binary Metal-Organic Gels With Tunable Porosity And Mixed Valence Metal Sites For Removal Of Dyes In Water, Asif Mahmood, Wei Xia, Nasir Mahmood, Qingfei Wang, Ruqiang Zou Jan 2015

Hierarchical Heteroaggregation Of Binary Metal-Organic Gels With Tunable Porosity And Mixed Valence Metal Sites For Removal Of Dyes In Water, Asif Mahmood, Wei Xia, Nasir Mahmood, Qingfei Wang, Ruqiang Zou

Australian Institute for Innovative Materials - Papers

Hierarchical heteronuclear metal-organic gels (MOGs) based on iron (Fe) and aluminium (Al) metal-organic framework (MOF) backbones bridged by tri-carboxylate ligands have firstly been synthesized by simple solvothermal method. Monometallic MOGs based on Fe or Al give homogenous monoliths, which have been tuned by introduction of heterogeneity in the system (mismatched growth). The developed gels demonstrate that surface areas, pore volumes and pore sizes can be readily tuned by optimizing heterogeneity. The work also elaborates effect of heterogeneity on size of MOG particles which increase substantially with increasing heterogeneity as well as obtaining mixed valence sites in the gels. High surface …

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Trap-Assisted Transport And Non-Uniform Charge Distribution In Sulphur-Rich Pbs Colloidal Quantum Dot-Based Solar Cells With Selective Contacts, Victor Malgras, Guanran Zhang, Andrew Nattestad, Tracey M. Clarke, Attila J. Mozer, Yusuke Yamauchi, Jung Ho Kim Jan 2015

Trap-Assisted Transport And Non-Uniform Charge Distribution In Sulphur-Rich Pbs Colloidal Quantum Dot-Based Solar Cells With Selective Contacts, Victor Malgras, Guanran Zhang, Andrew Nattestad, Tracey M. Clarke, Attila J. Mozer, Yusuke Yamauchi, Jung Ho Kim

Australian Institute for Innovative Materials - Papers

This study reports evidences of dispersive transport in planar PbS colloidal quantum dots heterojunction-based devices as well as the effect of incorporating a MoO3 hole selective layer on the charge extraction behavior. Steady state and transient characterization techniques are employed to determine the complex recombination processes involved in such devices. The addition of a selective contact drastically improves the device efficiency up to 3.15 % (especially through the photocurrent and series resistance) and extends the overall charge lifetime by suppressing the main first-order recombination pathway observed in device without MoO3. The lifetime and mobility calculated for our sulphur-rich PbS-based devices …

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Research Progress On Design Strategies, Synthesis And Performance Of Limn2o4-Based Cathodes, Fangxin Mao, Wei Dong Guo, Jianmin Ma Jan 2015

Research Progress On Design Strategies, Synthesis And Performance Of Limn2o4-Based Cathodes, Fangxin Mao, Wei Dong Guo, Jianmin Ma

Australian Institute for Innovative Materials - Papers

Spinel LiMn2O4 (LMO)-based composites, due to their combination of low toxicity, abundant natural resources, and excellent electrochemical performance, are regarded as promising candidate cathode materials for lithium ion batteries. Current energy storage demands are not being met with existing materials, however, because of their defects, such as fast capacity fading, low rate capability, and low specific capacity in practical applications. Manganese dissolution during electrochemical processes bears the major responsibility for capacity loss, apart from the electrolyte factor. Low electrical conductivity, low ionic diffusion efficiency, and large structural variation have adverse effects on the electrochemical performance of materials. With respect to …

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Vanadium-Based Nanostructure Materials For Secondary Lithium Battery Applications, Hui Teng Tan, Xianhong Rui, Wenping Sun, Qingyu Yan, Tuti M. Lim Jan 2015

Vanadium-Based Nanostructure Materials For Secondary Lithium Battery Applications, Hui Teng Tan, Xianhong Rui, Wenping Sun, Qingyu Yan, Tuti M. Lim

Australian Institute for Innovative Materials - Papers

Vanadium-based materials, such as V2O5, LiV3O8, VO2(B) and Li3V2(PO4)3 are compounds that share the characteristic of intercalation chemistry. Their layered or open frameworks allow facile ion movement through the interspaces, making them promising cathodes for LIB applications. To bypass bottlenecks occurring in the electrochemical performances of vanadium-based cathodes that derive from their intrinsic low electrical conductivity and ion diffusion coefficients, nano-engineering strategies have been implemented to "create" newly emerging properties that are unattainable at the bulk solid level. Integrating this concept into vanadium-based cathodes represents a promising way to circumvent the aforementioned problems as nanostructuring offers potential improvements in electrochemical …

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Coherent And Tunable Terahertz Radiation From Graphene Surface Plasmon Polarirons Excited By Cyclotron Electron Beam, Tao Zhao, Sen Gong, Min Hu, Renbin Zhong, Diwei Liu, Xiaoxing Chen, Ping Zhang, Xinran Wang, C Zhang, Peiheng Wu, Shenggang Liu Jan 2015

Coherent And Tunable Terahertz Radiation From Graphene Surface Plasmon Polarirons Excited By Cyclotron Electron Beam, Tao Zhao, Sen Gong, Min Hu, Renbin Zhong, Diwei Liu, Xiaoxing Chen, Ping Zhang, Xinran Wang, C Zhang, Peiheng Wu, Shenggang Liu

Australian Institute for Innovative Materials - Papers

Terahertz (THz) radiation can revolutionize modern science and technology. To this date, it remains big challenges to develop intense, coherent and tunable THz radiation sources that can cover the whole THz frequency region either by means of only electronics (both vacuum electronics and semiconductor electronics) or of only photonics (lasers, for example, quantum cascade laser). Here we present a mechanism which can overcome these difficulties in THz radiation generation. Due to the natural periodicity of 2π of both the circular cylindrical graphene structure and cyclotron electron beam (CEB), the surface plasmon polaritions (SPPs) dispersion can cross the light line of …

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Some Remarks On Distributional Chaos For Bounded Linear Operators, Lvlin Luo, Bingzhe Hou Jan 2015

Some Remarks On Distributional Chaos For Bounded Linear Operators, Lvlin Luo, Bingzhe Hou

Turkish Journal of Mathematics

The aim of this paper is to study distributional chaos for bounded linear operators. We show that distributional chaos of type k \in {1,2} is an invariant of topological conjugacy between two bounded linear operators. We give a necessary condition for distributional chaos of type 2 where it is possible to distinguish distributional chaos and Li--Yorke chaos. Following this condition, we compare distributional chaos with other well-studied notions of chaos for backward weighted shift operators and give an alternative proof to the one where strong mixing does not imply distributional chaos of type 2 (Martínez-Giménez F, Oprocha P, Peris A. …

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On Condition $(Pwp)_{W}$ For $S$-Posets, Xingliang Liang, Yanfeng Luo Jan 2015

On Condition $(Pwp)_{W}$ For $S$-Posets, Xingliang Liang, Yanfeng Luo

Turkish Journal of Mathematics

Golchin and Rezaei (Commun Algebra 2009; 37: 1995--2007) introduced the weak version of Condition $(PWP)$ for $S$-posets, called Condition $(PWP)_{w}$. In this paper, we continue to study this condition. We first present a necessary and sufficient condition under which the $S$-poset $A(I)$ satisfies Condition $(PWP)_{w}$. Furthermore, we characterize pomonoids $S$ over which all cyclic (Rees factor) $S$-posets satisfy Condition $(PWP)_{w}$, and pomonoids $S$ over which all Rees factor $S$-posets satisfying Condition $(PWP)_{w}$ have a certain property. Finally, we consider direct products of $S$-posets satisfying Condition $(PWP)_{w}$.

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The Iteration Digraphs Of Finite Commutative Rings, Yangjiang Wei, Gaohua Tang Jan 2015

The Iteration Digraphs Of Finite Commutative Rings, Yangjiang Wei, Gaohua Tang

Turkish Journal of Mathematics

For a finite commutative ring $S$ (resp., a finite abelian group $S$) and a positive integer $k\geqslant2$, we construct an iteration digraph $G(S, k)$ whose vertex set is $S$ and for which there is a directed edge from $a\in S$ to $b\in S$ if $b=a^k$. We generalize some previous results of the iteration digraphs from the ring $\mathbb{Z}_n$ of integers modulo $n$ to finite commutative rings, and establish a necessary and sufficient condition for $G(S, k_1)$ and $G(S, k_2)$ to be isomorphic for any finite abelian group $S$.

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