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Full-Text Articles in Physical Sciences and Mathematics

Direct Observation Of Liquid-Like Behavior Of A Single Au Grain Boundary, Gilberto Casillas, Arturo Ponce, Jesus Velazquez-Salazar, M Jose-Yacaman Jan 2013

Direct Observation Of Liquid-Like Behavior Of A Single Au Grain Boundary, Gilberto Casillas, Arturo Ponce, Jesus Velazquez-Salazar, M Jose-Yacaman

Australian Institute for Innovative Materials - Papers

Behavior of matter at the nanoscale differs fromthat of the bulk due to confinement and surface effects. Here, we report a direct observation of liquid-like behavior of a single grain boundary formed by cold-welding Au nanoparticles, 40 nm in size, by mechanical manipulation in situ TEM. The grain boundary rotates almost freely due to the free surfaces and can rotate about 90 degrees. The grain boundary sustains more stress than the bulk, confirming a strong bonding between the nanoparticles.Moreover, this technique allows the measurement of the surface diffusion coefficient from experimental observations, which we compute for the Au nanoparticles. This …


Flux Pinning Mechanism In Bafe1.9ni0.1as2 Single Crystals: Evidence For Fluctuation In Mean Free Path Induced Pinning, M Shahbazi-Manshadi, X L Wang, K Y Choi, S X. Dou Jan 2013

Flux Pinning Mechanism In Bafe1.9ni0.1as2 Single Crystals: Evidence For Fluctuation In Mean Free Path Induced Pinning, M Shahbazi-Manshadi, X L Wang, K Y Choi, S X. Dou

Australian Institute for Innovative Materials - Papers

The flux pinning mechanism of BaFe1.9Ni0.1As2 superconducting crystals have been investigated systematically by magnetic measurements up to 13 T at various temperatures. The field dependence of the critical current density, Jc, was analysed within the collective pinning model. A remarkably good agreement between the experimental results and theoretical dl pinning curve is obtained, which indicates that pinning in BaFe1.9Ni0.1As2 crystal originates from spatial variation of the mean free path. Moreover, the normalized pinning force density, Fp, curves versus h1/4B/Birr (Birr is the irreversibility field) were scaled using the Dew-Hughes model. Analysis suggests that point pinning alone cannot explain the observed …


Bio-Ink Properties And Printability For Extrusion Printing Living Cells, Johnson H. Y Chung, Sina Naficy, Zhilian Yue, Robert Kapsa, Anita Quigley, Simon E. Moulton, Gordon G. Wallace Jan 2013

Bio-Ink Properties And Printability For Extrusion Printing Living Cells, Johnson H. Y Chung, Sina Naficy, Zhilian Yue, Robert Kapsa, Anita Quigley, Simon E. Moulton, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Additive biofabrication (3D bioprinting) makes it possible to create scaffolds with precise geometries, control over pore interconnectivity and architectures that are not possible with conventional techniques. Inclusion of cells within the ink to form a “bio-ink” presents the potential to print 3D structures that can be implanted into damaged/diseased tissue to promote highly controlled cell-based regeneration and repair. The properties of an ‘ink’ are defined by its formulation and critically influence the delivery and integrity of structure formed. Importantly, the ink properties need to conform to biological requirements necessary for the cell system that they are intended to support and …


Highly Uniform Tio2/Sno2/Carbon Hybrid Nanofibers With Greatly Enhanced Lithium Storage Performance, Zunxian Yang, Qing Meng, Zaiping Guo, Xuebin Yu, Tailiang Guo, Rong Zeng Jan 2013

Highly Uniform Tio2/Sno2/Carbon Hybrid Nanofibers With Greatly Enhanced Lithium Storage Performance, Zunxian Yang, Qing Meng, Zaiping Guo, Xuebin Yu, Tailiang Guo, Rong Zeng

Australian Institute for Innovative Materials - Papers

Highly uniform, relatively large area TiO2/SnO 2/carbon hybrid nanofibers were synthesized by a simple method based on thermal pyrolysis and oxidation of an as-spun titanium-tin/polyacrylonitrile nanoweb composite in an argon atmosphere. This novel composite features the uniform dispersion and encapsulation of highly uniform nanoscale TiO 2/SnO2 crystals in a porous carbon matrix. The high porosity of the nanofiber composite material, together with the conductive carbon matrix, enhanced the electrochemical performance of the TiO 2/SnO2/carbon nanofiber electrode. The TiO 2/SnO2/carbon nanofiber electrode displays a reversible capacity of 442.8 mA h g-1 for up to 100 cycles, and exhibits excellent rate capability. …


Limiting Thermomagnetic Avalanches In Superconducting Films By Stop-Holes, F Colauto, J I. Vestgarden, A M H De Andrade, A A M Oliveira, Wilson Aires Ortiz, Tom H. Johansen Jan 2013

Limiting Thermomagnetic Avalanches In Superconducting Films By Stop-Holes, F Colauto, J I. Vestgarden, A M H De Andrade, A A M Oliveira, Wilson Aires Ortiz, Tom H. Johansen

Australian Institute for Innovative Materials - Papers

It is demonstrated that circular holes in superconducting films of Nb can arrest the propagation of thermomagnetic avalanches. The effect was found over a range of temperatures where the material is susceptible to this instability. For other hole shapes, like square and triangular, the sharp corners provoke secondary avalanches, thus extending the breakdown. Making use of circular stop-holes can become a practical way to limit thermomagnetic breakdown in superconducting films.


One-Pot Green Synthesis Of Ag Nanoparticles-Decorated Reduced Graphene Oxide For Efficient Nonenzymatic H2o2 Biosensor, Mingyan Wang, Tao Shen, Meng Wang, Dongen Zhang, Jun Chen Jan 2013

One-Pot Green Synthesis Of Ag Nanoparticles-Decorated Reduced Graphene Oxide For Efficient Nonenzymatic H2o2 Biosensor, Mingyan Wang, Tao Shen, Meng Wang, Dongen Zhang, Jun Chen

Australian Institute for Innovative Materials - Papers

Ag nanoparticles (AgNP) with an average size of 12 nm are successfully decorated on the reduced graphene oxide (rGO) sheets through a simple one-pot hydrothermal method using gallic acid as the reducing agent. This AgNP/rGO hybrid has been successfully applied in the catalytic performance toward the reduction of H2O2. The nonenzymatic sensor demonstrates a linear relationship in a wide concentration range of 0.05-5 mM (R=0.999), and a high sensitivity of 255 μA cm-2 mM-1 to the detection of H2O2.


Enhancing Superconducting Properties Of Mgb2 Pellets By Addition Of Amorphous Magnetic Ni-Co-B Nanoparticles, Mislav Mustapic, Josip Horvat, Md Shahriar Hossain, Zeljko Skoko, S X. Dou Jan 2013

Enhancing Superconducting Properties Of Mgb2 Pellets By Addition Of Amorphous Magnetic Ni-Co-B Nanoparticles, Mislav Mustapic, Josip Horvat, Md Shahriar Hossain, Zeljko Skoko, S X. Dou

Australian Institute for Innovative Materials - Papers

Amorphous magnetic Ni-Co-B nanoparticles with an average size of 5 nm were added to precursor powders of MgB2 superconductor. The preparation procedure for MgB2 pellets was optimized for obtaining the best critical current density (Jc) at elevated magnetic fields. Addition of Ni-Co-B decreases the Jc for heat treatment of precursor powders at 650 ° C. Heat treatments at 770 ° C and higher improve Jc at 20 and 5 K. This improvement occurs at both temperatures through the increase of the effective connectivity between MgB2 crystals. Vortex pinning was enhanced at 5 K, but not at 20 K. Ni-Co-B nanoparticles …


Time-Of-Flight Polarized Neutron Reflectometry On Platypus: Status And Future Developments, T Saerbeck, D L. Cortie, S Bruck, J Bertinshaw, S A. Holt, A Nelson, M James, W T. Lee, F Klose Jan 2013

Time-Of-Flight Polarized Neutron Reflectometry On Platypus: Status And Future Developments, T Saerbeck, D L. Cortie, S Bruck, J Bertinshaw, S A. Holt, A Nelson, M James, W T. Lee, F Klose

Australian Institute for Innovative Materials - Papers

Time-of-flight (ToF) polarized neutron reflectometry enables the detailed investigation of depth-resolved magnetic structures in thin film and multilayer magnetic systems. The general advantage of the time-of-flight mode of operation over monochromatic instruments is a decoupling of spectral shape and polarization of the neutron beam with variable resolution. Thus, a wide Q-range can be investigated using a single angle of incidence, with resolution and flux well-adjusted to the experimental requirement. Our paper reviews the current status of the polarization equipment of the ToF reflectometer PLATYPUS and presents first results obtained on stratified Ni80Fe20/α-Fe2O3 films, revealing the distribution of magnetic moments in …


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 …


Modulation Of The Properties Of Thin Ferromagnetic Films With An Externally Applied Electric Field In Ferromagnetic/Piezoelectric/Ferromagnetic Hybrids, D Stamopoulos, M Zeibekis, Shujun Zhang Jan 2013

Modulation Of The Properties Of Thin Ferromagnetic Films With An Externally Applied Electric Field In Ferromagnetic/Piezoelectric/Ferromagnetic Hybrids, D Stamopoulos, M Zeibekis, Shujun Zhang

Australian Institute for Innovative Materials - Papers

In many cases, technological advances are based on artificial low-dimensional structures of heterogeneous constituents, thus called hybrids, that when come together they provide stand-alone entities that exhibit entirely different properties. Such hybrids are nowadays intensively studied since they are attractive for both basic research and oncoming practical applications. Here, we studied hybrids constituted of piezoelectric (PE) and ferromagnetic (FM) components in the form FM/PE/FM, ultimately aiming to provide means for the controlled modulation of the properties of the FM electrodes, originating from the strain imposed to them by the PE mediator when an electric field is applied. The PE component …


Crystal Growth, Structure And Thermal Properties Of Noncentrosymmetric Single Crystals Prca4o(Bo3)3+, Fapeng Yu, Shujun Zhang, Xiufeng Cheng, Xiulan Duan, Tingfeng Ma, Xian Zhao Jan 2013

Crystal Growth, Structure And Thermal Properties Of Noncentrosymmetric Single Crystals Prca4o(Bo3)3+, Fapeng Yu, Shujun Zhang, Xiufeng Cheng, Xiulan Duan, Tingfeng Ma, Xian Zhao

Australian Institute for Innovative Materials - Papers

Noncentrosymmetric praseodymium calcium oxyborate single crystals, PrCa4O(BO3)3 (PrCOB), were grown by the Czochralski technique. The monoclinic unit cell parameters were found to be a = 8.177 Å, b = 16.157 Å, c = 3.629 Å and Z = 2 with space group Cm. Crystal density was measured using the Archimedes method, being on the order of 3.47 g cm-3. Thermal properties of PrCOB were investigated, where the specific heat was found to be 0.63 J g-1 °C-1 at room temperature, increasing to 0.85 J g-1°C-1 at 700°C. The thermal expansion coefficients were measured to be α11 = 7.99, α22 = …


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 …


Levetiracetam-Loaded Biodegradable Polymer Implants In The Tetanus Toxin Model Of Temporal Lobe Epilepsy In Rats, Amy J. Halliday, Toni E. Campbell, Timothy S. Nelson, Karen J. Mclean, Gordon G. Wallace, Mark J. Cook Jan 2013

Levetiracetam-Loaded Biodegradable Polymer Implants In The Tetanus Toxin Model Of Temporal Lobe Epilepsy In Rats, Amy J. Halliday, Toni E. Campbell, Timothy S. Nelson, Karen J. Mclean, Gordon G. Wallace, Mark J. Cook

Australian Institute for Innovative Materials - Papers

Approximately one-third of people with epilepsy receive insufficient benefit from currently available anticonvulsant medication, and some evidence suggests that this may be due to a lack of effective penetration into brain parenchyma. The current study investigated the ability of biodegradable polymer implants loaded with levetiracetam to ameliorate seizures following implantation above the motor cortex in the tetanus toxin model of temporal lobe epilepsy in rats. The implants led to significantly shorter seizures and a trend towards fewer seizures for up to 1 week. The results of this study indicate that drug-eluting polymer implants represent a promising evolving treatment option for …


Structurally Homogeneous Mgb2 Superconducting Wires Through Economical Wet Mixing Process, Md Shahriar A. Hossain, Ashkan Motaman, Xun Xu, Khay Way See, Ozlem Cicek, Hasan Agil, Ercan Ertekin, Ali Gencer, Kookchae Cheong, Minoru Maeda, S X. Dou Jan 2013

Structurally Homogeneous Mgb2 Superconducting Wires Through Economical Wet Mixing Process, Md Shahriar A. Hossain, Ashkan Motaman, Xun Xu, Khay Way See, Ozlem Cicek, Hasan Agil, Ercan Ertekin, Ali Gencer, Kookchae Cheong, Minoru Maeda, S X. Dou

Australian Institute for Innovative Materials - Papers

We evaluate the effects of the mixing process between the starting materials on the structural and superconducting properties of carbon-doped MgB2 wires. The critical current density, n-value, amount of MgO, and critical temperature are obviously dependent on the mixing process, while the microstructure, i.e., grain size, is not sensitive. In our study, the wet-mixing process in toluene enables more homogenous mixing between the starting materials, resulting in superior J(c) and n-value.


Raman Scattering Studies Of Strain Effects In (100) And (311)B Gaas 1-Xbix Epitaxial Layers, J A. Steele, Roger A. Lewis, M Henini, O M. Lemine, A Alkaoud Jan 2013

Raman Scattering Studies Of Strain Effects In (100) And (311)B Gaas 1-Xbix Epitaxial Layers, J A. Steele, Roger A. Lewis, M Henini, O M. Lemine, A Alkaoud

Australian Institute for Innovative Materials - Papers

We report room-temperature Raman studies of strained (100) and (311)B GaAs1-xBix epitaxial layers for x ≤ 0.039. The Raman spectra exhibit a two-mode behavior, as well as disorder-activated GaAs-like phonons. The experimental results show that the GaAs-like LO(Γ) mode experiences a strong composition-dependent redshift as a result of alloying. The peak frequency decreases linearly from the value for pure GaAs (∼293 cm-1) with the alloyed Bi fraction x and the introduced in-plane lattice strain ε, by Δ ω LO = Δ ω alloy-Δ ω strain. X-ray diffraction measurements are used to determine x and ε allowing Δ ω alloy to …


Studying Inhomogeneity Of Organic Coatings Using Wire Beam Multielectrode And Physicomechanical Testing, Sina S. Jamali, D J. Mills Jan 2013

Studying Inhomogeneity Of Organic Coatings Using Wire Beam Multielectrode And Physicomechanical Testing, Sina S. Jamali, D J. Mills

Australian Institute for Innovative Materials - Papers

The effect of thickness, curing temperature and solvent on the structural inhomogeneity of several types of organic coatings has been investigated. The local distribution of electrochemical resistance was studied using a wire beam multielectrode array, while the inhomogeneity at a larger scale was examined using ∼3 cm2 area detached coatings. Physicomechanical tests were also employed to address the structural changes occurring because of variation in curing temperature and the type (or absence) of solvent. Results acquired by wire beam electrode and from the detached coatings showed that increasing the thickness and curing temperature improves the homogeneity of the coating as …


Signature Of Aromatic Carbons In The Terahertz Spectroscopy Of Bio-Chars, L M. Lepodise, J Horvat, Roger A. Lewis Jan 2013

Signature Of Aromatic Carbons In The Terahertz Spectroscopy Of Bio-Chars, L M. Lepodise, J Horvat, Roger A. Lewis

Australian Institute for Innovative Materials - Papers

The potential of terahertz spectroscopy in distinguishing aromatic carbon compounds in bio-chars is The potential of terahertz spectroscopy in distinguishing aromatic carbon compounds in bio-chars is demonstrated. Several types of biochar samples were measured and compared with the THz spectra of pure aromatic compounds. Infrared spectra were modeled with B3LYP and mP2PLYP methods. Modeling could not identify accurately each of the absorption lines. However modeling shows that one of the lines close to 500 cm-1 is due to vibrations of carbon rings, which can be used for identification of aromatic carbons in biochars. and compared with the THz spectra of …


Electrochemically Synthesized Stretchable Polypyrrole/Fabric Electrodes For Supercapacitor, Binbin Yue, Caiyun Wang, Xin Ding, Gordon G. Wallace Jan 2013

Electrochemically Synthesized Stretchable Polypyrrole/Fabric Electrodes For Supercapacitor, Binbin Yue, Caiyun Wang, Xin Ding, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

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 cotton fabric coated with polypyrrole as electrode for stretchable supercapacitors. Polypyrrole was synthesized on the Au coated fabric via an electrochemical polymerization process with p-toluenesulfonic acid (p-TS) as dopant from acetonitrile solution. This material was characterized with FESEM, tensile stress, and studied as a supercapacitor electrode in 1.0 M NaCl. This conductive textile electrode can sustain up to 140% strain without electric failure. It delivers a high specific …


2-(10′,10′-Dimethyl-3′-Sulfanylidene-4′- Azatricyclo[5.2.1.01,5]Decan-2′-Yl)-10,10-Dimethyl-4- Azatricyclo[5.2.1.01,5]Decane-3-Thione, Ashley Walker, Craig M. Forsyth, Patrick Perlmutter Jan 2013

2-(10′,10′-Dimethyl-3′-Sulfanylidene-4′- Azatricyclo[5.2.1.01,5]Decan-2′-Yl)-10,10-Dimethyl-4- Azatricyclo[5.2.1.01,5]Decane-3-Thione, Ashley Walker, Craig M. Forsyth, Patrick Perlmutter

Australian Institute for Innovative Materials - Papers

The title compound, C28H40N2O2S2, was obtained as a minor product from an anti-aldol reaction between the corresponding N-propionyl­thiol­actam and benzaldehyde. The asymmetric unit contains one half-molecule, which is completed by inversion symmetry. The molecule displays a nearly eclipsed conformation along the central C-C bond with a C-C-C-C- torsion angle of 20.4 (3)°.


Tubular Graphitic-C 3 N 4 : A Prospective Material For Energy Storage And Green Photocatalysis, Muhammad Nawaz Tahir, Chuanbao Cao, Faheem K. Butt, Faryal Idrees, Nasir Mahmood, Zulfiqar Ali, Imran Aslam, M Tanveer, Muhammad Rizwan, Tariq Mahmood Jan 2013

Tubular Graphitic-C 3 N 4 : A Prospective Material For Energy Storage And Green Photocatalysis, Muhammad Nawaz Tahir, Chuanbao Cao, Faheem K. Butt, Faryal Idrees, Nasir Mahmood, Zulfiqar Ali, Imran Aslam, M Tanveer, Muhammad Rizwan, Tariq Mahmood

Australian Institute for Innovative Materials - Papers

We have established a facile and scaleable approach to fabricate tubular graphitic-C3N4 using melamine. The construction of the unique tubular morphology is a result of the pre-treatment of melamine with HNO3. Herein, for the first time, we have explored the electrochemical properties of g-C3N4 as an electrode material for supercapacitors. Tubular g-C3N4 has significant advantages due to its distinctive morphology, high surface area (182.61 m2 g-1) and combination of carbon with nitrogen. Therefore, tubular g-C3N4 demonstrated a good specific capacitance of 233 F g-1 at a current density of 0.2 A g-1 in 6 M …


Polyamide 6/Multiwalled Carbon Nanotubes Nanocomposites With Modified Morphology And Thermal Properties, Nasir Mahmood, Mohammad Islam, Asad Hameed, Shaukat Saeed Jan 2013

Polyamide 6/Multiwalled Carbon Nanotubes Nanocomposites With Modified Morphology And Thermal Properties, Nasir Mahmood, Mohammad Islam, Asad Hameed, Shaukat Saeed

Australian Institute for Innovative Materials - Papers

Pure polyamide 6 (PA6) and polyamide 6/carbon nanotube (PA6/CNT) composite samples with 0.5 weight percent loading of pristine or functionalized CNTs were made using a solution mixing technique. Modification of nanotube surface as a result of chemical functionalization was confirmed through the presence of lattice defects as examined under high-resolution transmission electron microscope and absorption bands characteristic of carboxylic, sulfonic and amine chemical groups. Microstructural examination of the cryogenically fractured surfaces revealed qualitative information regarding CNT dispersion within PA6 matrix and interfacial strength. X-ray diffraction studies indicated formation of thermodynamically more stable α-phase crystals. Thermogravimetric analysis revealed that CNT incorporation …


Variation Of Pinning Mechanism And Enhancement Of Critical Current Density In Mgb2 Bulk Containing Self-Generated Coherent Mgb4 Impurity, Qi Cai, Yongchang Liu, Zongqing Ma, Huijun Li, Liming Yu Jan 2013

Variation Of Pinning Mechanism And Enhancement Of Critical Current Density In Mgb2 Bulk Containing Self-Generated Coherent Mgb4 Impurity, Qi Cai, Yongchang Liu, Zongqing Ma, Huijun Li, Liming Yu

Australian Institute for Innovative Materials - Papers

Bulk MgB2, with self-generated MgB4 pinning centers, have experienced two-step sintering process, initially at 750°C and then 900-1000°C. On the contrary to the widely accepted point that MgB 4 deteriorates superconductivity, it was found that MgB4 played a significant role in enhancing critical current density. The precipitation pattern of MgB4 was studied from the lattice scale images. It was observed that the initial coherent relation between the MgB 4 and the matrix was destroyed to become semi-coherent and even incoherent as the second-step sintering temperature increased. Owing to the lattice distortion caused by the elastic accommodation of the coherent interface, …


Direct Observation Of Domain Wall Motion And Novel Dielectric Loss In 0.23pb(In1/2nb1/2)O3-0.42pb(Mg1/3 Nb2/3)O3-0.35pbtio3 Crystals, Dabin Lin, Zhenrong Li, Fei Li, Shujun Zhang Jan 2013

Direct Observation Of Domain Wall Motion And Novel Dielectric Loss In 0.23pb(In1/2nb1/2)O3-0.42pb(Mg1/3 Nb2/3)O3-0.35pbtio3 Crystals, Dabin Lin, Zhenrong Li, Fei Li, Shujun Zhang

Australian Institute for Innovative Materials - Papers

Domain wall motion was directly observed at temperatures near to the monoclinic-to-tetragonal phase transition temperature (TM-T) in [001]-oriented 0.23Pb(In1/2Nb1/2)O3-0. 42Pb(Mg1/3Nb2/3)O3-0.35PbTiO3 (0.23PIN-0.42PMN-0.35PT) single crystals using a polarizing light microscope, and evident 90°and 180°domain switches were observed near the Curie temperature (TC). Two dielectric loss anomalies were observed at temperatures near TM-T in the [001]-oriented PIN-PMN-PT single crystals, while an additional dielectric loss peak was found at temperatures a few degrees below TC, which was associated with domain wall motion. Based on the domain structure observations, a domain switching mechanism was proposed to explain the novel dielectric loss peak at several degrees …


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 …


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 …


Fluidic Automation Of Nitrate And Nitrite Bioassays In Whole Blood By Dissolvable-Film Based Centrifugo-Pneumatic Actuation, Charles E. Nwankire, Di-Sien S. Chan, Jennifer Gaughran, Robert Burger, Robert A. Gorkin Iii, Jens Ducree Jan 2013

Fluidic Automation Of Nitrate And Nitrite Bioassays In Whole Blood By Dissolvable-Film Based Centrifugo-Pneumatic Actuation, Charles E. Nwankire, Di-Sien S. Chan, Jennifer Gaughran, Robert Burger, Robert A. Gorkin Iii, Jens Ducree

Australian Institute for Innovative Materials - Papers

This paper demonstrates the full centrifugal microfluidic integration and automation of all liquid handling steps of a 7-step fluorescence-linked immunosorbent assay (FLISA) for quantifying nitrate and nitrite levels in whole blood within about 15 min. The assay protocol encompasses the extraction of metered plasma, the controlled release of sample and reagents (enzymes, co-factors and fluorescent labels), and incubation and detection steps. Flow control is implemented by a rotationally actuated dissolvable film (DF) valving scheme. In the valves, the burst pressure is primarily determined by the radial position, geometry and volume of the valve chamber and its inlet channel and can …


Nonlocal Electrodynamics Of Normal And Superconducting Films, J I. Vestgarden, P Mikheenko, Y M. Galperin, T H Johansen Jan 2013

Nonlocal Electrodynamics Of Normal And Superconducting Films, J I. Vestgarden, P Mikheenko, Y M. Galperin, T H Johansen

Australian Institute for Innovative Materials - Papers

Electrically conducting films in a time-varying transverse applied magnetic field are considered. Their behavior is strongly influenced by the self-field of the induced currents, making the electrodynamics nonlocal, and consequently difficult to analyze both numerically and analytically. We present a formalism which allows many phenomena related to superconducting and Ohmic films to be modeled and analyzed. The formalism is based on the Maxwell equations and a material current-voltage characteristics, linear for normal metals and nonlinear for superconductors, plus a careful account of the boundary conditions. For Ohmic films, we consider the response to a delta function source-field turned on instantly. …


Biofunctionalized Anti-Corrosive Silane Coatings For Magnesium Alloys, Xiao Liu, Zhilian Yue, Tony Romeo, Jan Weber, Torsten Scheuermann, Simon E. Moulton, Gordon G. Wallace Jan 2013

Biofunctionalized Anti-Corrosive Silane Coatings For Magnesium Alloys, Xiao Liu, Zhilian Yue, Tony Romeo, Jan Weber, Torsten Scheuermann, Simon E. Moulton, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Biodegradable magnesium alloys are advantageous in various implant applications, as they reduce the risks associated with permanent metallic implants. However, a rapid corrosion rate is usually a hindrance in biomedical applications. Here we report a facile two step procedure to introduce multifunctional, anti-corrosive coatings on Mg alloys, such as AZ31. The first step involves treating the NaOH-activated Mg with bistriethoxysilylethane to immobilize a layer of densely crosslinked silane coating with good corrosion resistance; the second step is to impart amine functionality to the surface by treating the modified Mg with 3-amino-propyltrimethoxysilane. We characterized the two-layer anticorrosive coating of Mg alloy …


Flexible Supercapacitors - Development Of Bendable Carbon Architectures, Zhiqiang Niu, Lili Liu, Peter C. Sherrell, Jun Chen, Xiaodong Chen Jan 2013

Flexible Supercapacitors - Development Of Bendable Carbon Architectures, Zhiqiang Niu, Lili Liu, Peter C. Sherrell, Jun Chen, Xiaodong Chen

Australian Institute for Innovative Materials - Papers

As energy storage devices, Supercapacitors (SCs), also known as electrochemical capacitors, possess high power densities, excellent reversibility and long cycle life. SCs could be applied to diverse fields including electric vehicles, pulse power applications and portable devices. Flexible SCs have attracted significant attention for powering recently developed portable, flexible and wearable electronics. During the past several years, a variety of bendable carbon-based electrode architechtures and flexible SC devices with different designs have been successfully prepared. In this review, we will describe recent developments in the preparation of such bendable carbon-based electrode architechtures and the subsequent design of flexible SC devices. …


Surface Modification Of Polypyrrole/Biopolymer Composites For Controlled Protein And Cellular Adhesion, Paul J. Molino, Binbin Zhang, Gordon G. Wallace, Timothy Hanks Jan 2013

Surface Modification Of Polypyrrole/Biopolymer Composites For Controlled Protein And Cellular Adhesion, Paul J. Molino, Binbin Zhang, Gordon G. Wallace, Timothy Hanks

Australian Institute for Innovative Materials - Papers

The ability to control the interaction between proteins and cells with biomaterials is critical for the effective application of materials for a variety of biomedical applications. Herein, the surface modification of the biological dopant dextran sulphate-doped polypyrrole (PPy-DS) with poly(ethylene glycol) to generate a biomaterial interface that is highly resistant to protein and cellular adhesion is described. Thiolated poly(ethylene glycol) (PEG-thiol) was covalently bound to PPy-DS backbone via a thiol-ene reaction. The surface resistance to an extracellular matrix protein fibronectin increased with increasing molecular weight and concentration of PEG-thiol, and was further optimised via increasing the reaction temperature and the …