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Full-Text Articles in Engineering

Investigating Sequence Patterns Of Collaborative Problem-Solving Behavior In The Online Collaborative Discussion Activity, Yafeng Zheng, Haogang Bao, Jun Shen, Xuesong Zhai Jan 2020

Investigating Sequence Patterns Of Collaborative Problem-Solving Behavior In The Online Collaborative Discussion Activity, Yafeng Zheng, Haogang Bao, Jun Shen, Xuesong Zhai

Faculty of Engineering and Information Sciences - Papers: Part B

Collaborative problem solving (CPS) is an influential human behavior affecting working performance and well-being. Previous studies examined CPS behavior from the perspective of either social or cognitive dimensions, which leave a research gap from the interactive perspective. In addition, the traditional sequence analysis method failed to combine time sequences and sub-problem sequences together while analyzing behavioral patterns in CPS. This study proposes a developed schema for the multidimensional analysis of CPS. A combination sequential analysis approach that comprises time sequences and sub-problem sequences is also employed to explore CPS patterns. A total of 191 students were recruited and randomly grouped …


Numerical Modelling Of Track Behavior Capturing Particle Breakage Under Dynamic Loading, Ngoc Trung Ngo, Buddhima Indraratna Jan 2020

Numerical Modelling Of Track Behavior Capturing Particle Breakage Under Dynamic Loading, Ngoc Trung Ngo, Buddhima Indraratna

Faculty of Engineering and Information Sciences - Papers: Part B

No abstract provided.


Fiber Element Simulation Of Interaction Behavior Of Local And Global Buckling In Axially Loaded Rectangular Concrete-Filled Steel Tubular Slender Columns Under Fire Exposure, Ghanim Mohammed Kamil, Qing Quan Liang, Muhammad N. S Hadi Jan 2019

Fiber Element Simulation Of Interaction Behavior Of Local And Global Buckling In Axially Loaded Rectangular Concrete-Filled Steel Tubular Slender Columns Under Fire Exposure, Ghanim Mohammed Kamil, Qing Quan Liang, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Slender rectangular thin-walled concrete-filled steel tubular (CFST) columns in composite building structures exposed to fire may experience the interaction of local and global buckling. Numerical investigations on the interaction buckling responses of such columns under fire exposure have been rarely reported. This paper describes a fiber-based computational model for the prediction of the fire-resistance and interaction responses of local and global buckling of concentrically-loaded slender CFST columns made of rectangular sections exposed to fire. The thermal analysis is undertaken to calculate the distribution of temperatures in the column cross-section considering the effects of the air gap between concrete and steel, …


Behavior Of Eccentrically Loaded Double Circular Steel Tubular Short Columns Filled With Concrete, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi Jan 2019

Behavior Of Eccentrically Loaded Double Circular Steel Tubular Short Columns Filled With Concrete, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part B

Circular concrete-filled double steel tubular (CFDST) columns in high-rise building structures possess high ductility and strength performance owing to the concrete confinement exerted by the external and internal circular steel tubes. However, the behavior of circular CFDST short columns that are loaded eccentrically has not been investigated either experimentally or numerically. Particularly, numerical studies on the moment-curvature responses, strength envelopes, confinement effects and moment distributions in circular CFDST beam-columns have not been reported. In this paper, experimental and computational investigations into the structural responses of circular CFDST short columns loaded eccentrically are presented. Nineteen short circular CFDST columns with various …


Behavior Of Self-Compacting Concrete Columns Reinforced Longitudinally With Steel Tubes, Muhammad N. S Hadi, Faez Alhussainy, M Neaz Sheikh Jan 2017

Behavior Of Self-Compacting Concrete Columns Reinforced Longitudinally With Steel Tubes, Muhammad N. S Hadi, Faez Alhussainy, M Neaz Sheikh

Faculty of Engineering and Information Sciences - Papers: Part B

This study investigates the behavior of self-compacting concrete (SCC) specimens reinforced with small-diameter steel tubes in lieu of reinforcing bars. Twenty specimens were cast and tested. Four specimens were reinforced with normal steel bars (reference specimens) and the remaining 16 with steel tubes. All specimens contained steel helices with a pitch of either 50 mm or 75 mm. Deformed steel bars of 16-mm diameter were used in the four reference specimens as longitudinal reinforcement. Steel tubes of 33.7-mm outside diameter with 2-mm wall thickness (ST33.7) and steel tubes of 26.9-mm outside diameter with 2.6-mm wall thickness (ST26.9) were used as …


Internal Energy Transfer In Dynamical Behavior Of Slightly Curved Shear Deformable Microplates, Mergen H. Ghayesh, Hamed Farokhi, Gursel Alici Jan 2016

Internal Energy Transfer In Dynamical Behavior Of Slightly Curved Shear Deformable Microplates, Mergen H. Ghayesh, Hamed Farokhi, Gursel Alici

Faculty of Engineering and Information Sciences - Papers: Part A

This paper investigates the internal energy transfer and modal interactions in the dynamical behavior of slightly curved microplates. Employing the third-order shear deformation theory, the microplate model is developed taking into account geometric nonlinearities as well as the modified couple stress theory; the initial curvature is modeled by an initial imperfection in the out-of-plane direction. The in-plane displacements and inertia are retained, and the coupled out-of-plane, rotational, and in-plane motion characteristics are analyzed. Specifically, continuous models are developed for kinetic and potential energies as well as damping and external works; these are balanced and reduced via Lagrange's equations along with …


Axial And Flexural Behavior Of Unreinforced And Frp Bar Reinforced Circular Concrete Filled Frp Tube Columns, Muhammad N. S Hadi, Qasim Khan, M Neaz Sheikh Jan 2016

Axial And Flexural Behavior Of Unreinforced And Frp Bar Reinforced Circular Concrete Filled Frp Tube Columns, Muhammad N. S Hadi, Qasim Khan, M Neaz Sheikh

Faculty of Engineering and Information Sciences - Papers: Part A

Fiber Reinforced Polymer (FRP) composites have emerged as a viable alternative of steel reinforcement due to higher ultimate tensile strength to weight ratio and corrosion resistance of FRP composites. Concrete Filled Fiber Reinforced Polymer Tube (CFFT) technique for new column construction has attracted significant research attention. This paper investigated the axial and flexural behavior of concrete filled Carbon FRP (CFRP) tube columns with and without CFRP bar and concrete filled Glass FRP (GFRP) tube columns with and without GFRP bar. The test results of 16 circular CFFT and four steel Reinforced Concrete (RC) specimens of 203-205 mm diameter and 800-812 …


Drained And Undrained Shear Behavior Of Compacted Coal Wash, Ana Heitor, Buddhima Indraratna, Chazath Kaliboullah, Cholachat Rujikiatkamjorn, Geoffrey Mcintosh Jan 2016

Drained And Undrained Shear Behavior Of Compacted Coal Wash, Ana Heitor, Buddhima Indraratna, Chazath Kaliboullah, Cholachat Rujikiatkamjorn, Geoffrey Mcintosh

Faculty of Engineering and Information Sciences - Papers: Part A

Coal wash is a granular waste material that is readily available in the vicinity of coal mining operations. While its potential use in structural fills has been recognized in the past, the effects of particle breakage on the geomechanical performance of the material have not been thoroughly investigated. In this paper, an experimental study on a selected coal wash is undertaken to characterize the influence of compaction and particle breakage on its corresponding stress-strain behavior. Particular emphasis is given to the role of compaction energy level and associated breakage incurred during compaction on the drained and undrained shearing behavior. The …


Correlation Between Zn-Rich Phase And Corrosion/Oxidation Behavior Of Sn-8zn-3bi Alloy, Xin Zhang, Chong Li, Zhiming Gao, Yongchang Liu, Zongqing Ma, Liming Yu, Hui Jun Li Jan 2016

Correlation Between Zn-Rich Phase And Corrosion/Oxidation Behavior Of Sn-8zn-3bi Alloy, Xin Zhang, Chong Li, Zhiming Gao, Yongchang Liu, Zongqing Ma, Liming Yu, Hui Jun Li

Faculty of Engineering and Information Sciences - Papers: Part A

The microstructure of Sn-8Zn-3Bi alloy was refined by increasing the solidification rate and the correlation between Zn-rich phase and the corrosion/oxidation behavior of the alloy was investigated. The Zn-rich phase transforms from coarse flakes to fine needles dispersed in the β-Sn matrix with the increase of the cooling rate. The transformation of Zn-rich precipitates enhances the anticorrosive ability of Sn-8Zn-3Bi alloy in 3.5 wt.% NaCl solution. On the contrary, Sn-8Zn-3Bi alloy with a fine needle-like Zn-rich phase shows poor oxidation resistance under air atmosphere, due to the fast diffusion of Zn atoms in Sn matrix.


Compressive Behavior Of Frp-Confined Concrete-Encased Steel Columns, Tao Yu, G Lin, Shi Shun Zhang Jan 2016

Compressive Behavior Of Frp-Confined Concrete-Encased Steel Columns, Tao Yu, G Lin, Shi Shun Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

FRP-confined concrete-encased steel I-section columns (FCSCs) are an emerging form of hybrid columns. An FCSC consists of an outer FRP tube, an encased steel section and a concrete infill. The FCSCs possess many advantages over conventional reinforced concrete columns, including the excellent corrosion resistance, excellent ductility and ease for construction. Existing studies on FCSCs, however, have been rather limited. This paper presents a combined experimental and theoretical study on the behavior of FCSCs under concentric and eccentric compression. The experimental program included the testing of a total of 14 specimens, with the main variables being the section configuration, the thickness …


Nonlinear Dynamical Behavior Of Axially Accelerating Beams: Three-Dimensional Analysis, Mergen H. Ghayesh, Hamed Farokhi Jan 2016

Nonlinear Dynamical Behavior Of Axially Accelerating Beams: Three-Dimensional Analysis, Mergen H. Ghayesh, Hamed Farokhi

Faculty of Engineering and Information Sciences - Papers: Part A

The three-dimensional (3D) nonlinear dynamics of an axially accelerating beam is examined numerically taking into account all of the longitudinal, transverse, and lateral displacements and inertia. Hamilton's principle is employed in order to derive the nonlinear partial differential equations governing the longitudinal, transverse, and lateral motions. These equations are transformed into a set of nonlinear ordinary differential equations by means of the Galerkin discretization technique. The nonlinear global dynamics of the system is then examined by time-integrating the discretized equations of motion. The results are presented in the form of bifurcation diagrams of Poincare maps, time histories, phase-plane portraits, Poincare …


Mechanical Properties And Tribological Behavior Of Aluminum Matrix Composites Reinforced With In-Situ Alb2 Particles, Linlin Yuan, Jingtao Han, Jing Liu, Zhengyi Jiang Jan 2016

Mechanical Properties And Tribological Behavior Of Aluminum Matrix Composites Reinforced With In-Situ Alb2 Particles, Linlin Yuan, Jingtao Han, Jing Liu, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part A

Aluminum matrix composites (AMCs) reinforced with in-situ AlB2 particles have been fabricated using a combination of powder metallurgy, hot rolling and solution treatment. The effects of boron content (7 and 12 wt%), hot rolling and heat treatment parameters on the microstructures and mechanical properties of the composites were investigated by means of scanning electron microscopy (SEM), tensile test and micro-hardness measurements. The friction coefficient, wear behavior and scratch morphology of the AMCs and pure aluminum were also studied using scratch tests. The hardness and wear properties are higher in a case of composites when compared to unreinforced matrix material.


Arc Erosion Behavior Of La-Doping Titanium-Zirconium-Molybdenum Alloy, Ping Hu, Bo-Liang Hu, Kuai-She Wang, Fan Yang, Rui Song, Zhi-Tao Yu, Qiang Wang, Wei-Cheng Cao, Dong-Xin Liu, Geng An, Lei Guo, Hai Liang Yu Jan 2016

Arc Erosion Behavior Of La-Doping Titanium-Zirconium-Molybdenum Alloy, Ping Hu, Bo-Liang Hu, Kuai-She Wang, Fan Yang, Rui Song, Zhi-Tao Yu, Qiang Wang, Wei-Cheng Cao, Dong-Xin Liu, Geng An, Lei Guo, Hai Liang Yu

Faculty of Engineering and Information Sciences - Papers: Part A

La-doping titanium-zirconium-molybdenum alloys have good arc erosion resistance performances, but there is no research about the changes during the arc erosion. Arc erosion characteristics of La-doping titanium-zirconium-molybdenum alloys after 5000 operations under direct current 20 V, 15 A and resistive load conditions were investigated using a JF04C test system. The results indicated that the probability distribution and change trend of arc energy and arc time during 5000 operations were similar and the relationship between arc time and arc energy followed exponential function. The change of arc energy with test number was consistent to electrical resistance. Oxide particles, crater and cracks …


Hydrostatic Compression Behavior And High-Pressure Stabilized Β-Phase In Γ-Based Titanium Aluminide Intermetallics, Klaus-Dieter Liss, Ken-Ichi Funakoshi, Rian J. Dippenaar, Yuji Higo, Ayumi Shiro, Mark H. Reid, Hiroshi Suzuki, Takahisa Shobu, Koichi Akita Jan 2016

Hydrostatic Compression Behavior And High-Pressure Stabilized Β-Phase In Γ-Based Titanium Aluminide Intermetallics, Klaus-Dieter Liss, Ken-Ichi Funakoshi, Rian J. Dippenaar, Yuji Higo, Ayumi Shiro, Mark H. Reid, Hiroshi Suzuki, Takahisa Shobu, Koichi Akita

Faculty of Engineering and Information Sciences - Papers: Part A

Titanium aluminides find application in modern light-weight, high-temperature turbines, such as aircraft engines, but suffer from poor plasticity during manufacturing and processing. Huge forging presses enable materials processing in the 10-GPa range, and hence, it is necessary to investigate the phase diagrams of candidate materials under these extreme conditions. Here, we report on an in situ synchrotron X-ray diffraction study in a large-volume press of a modern (α2 + γ) two-phase material, Ti-45Al-7.5Nb-0.25C, under pressures up to 9.6 GPa and temperatures up to 1686 K. At room temperature, the volume response to pressure is accommodated by the transformation γ → …


In Vitro Mechanical Fatigue Behavior Of Poly-Ɛ-Caprolactone Macroporous Scaffolds For Cartilage Tissue Engineering: Influence Of Pore Filling By A Poly(Vinyl Alcohol) Gel, J A. Panadero, L Vikingsson, J L. Gomez Ribelles, Senentxu Lanceros-Méndez, Vitor Sencadas Jan 2015

In Vitro Mechanical Fatigue Behavior Of Poly-Ɛ-Caprolactone Macroporous Scaffolds For Cartilage Tissue Engineering: Influence Of Pore Filling By A Poly(Vinyl Alcohol) Gel, J A. Panadero, L Vikingsson, J L. Gomez Ribelles, Senentxu Lanceros-Méndez, Vitor Sencadas

Faculty of Engineering and Information Sciences - Papers: Part A

Polymeric scaffolds used in regenerative therapies are implanted in the damaged tissue and submitted to repeated loading cycles. In the case of articular cartilage engineering, an implanted scaffold is typically subjected to long-term dynamic compression. The evolution of the mechanical properties of the scaffold during bioresorption has been deeply studied in the past, but the possibility of failure due to mechanical fatigue has not been properly addressed. Nevertheless, the macroporous scaffold is susceptible to failure after repeated loading-unloading cycles. In this work fatigue studies of polycaprolactone scaffolds were carried by subjecting the scaffold to repeated compression cycles in conditions simulating …


A Note On The Boundary Behavior For A Modified Green Function In The Upper-Half Space, Y Zhang, Valery Piskarev Jan 2015

A Note On The Boundary Behavior For A Modified Green Function In The Upper-Half Space, Y Zhang, Valery Piskarev

Faculty of Engineering and Information Sciences - Papers: Part A

Motivated by (Xu et al. in Bound. Value Probl. 2013:262, 2013) and (Yang and Ren in Proc. Indian Acad. Sci. Math. Sci. 124(2):175-178, 2014), in this paper we aim to construct a modified Green function in the upper-half space of the n-dimensional Euclidean space, which generalizes the boundary property of general Green potential.


Sodium Borohydride Hydrazinates: Synthesis, Crystal Structures, And Thermal Decomposition Behavior, Jianfeng Mao, Qinfen Gu, Zaiping Guo, Hua-Kun Liu Jan 2015

Sodium Borohydride Hydrazinates: Synthesis, Crystal Structures, And Thermal Decomposition Behavior, Jianfeng Mao, Qinfen Gu, Zaiping Guo, Hua-Kun Liu

Faculty of Engineering and Information Sciences - Papers: Part A

Metallic borohydride hydrazinates are novel boron- and nitrogen-based materials that appear to be promising candidates for chemical hydrogen storage. Herein, sodium borohydride hydrazinates, including NaBH4·N2H4 and NaBH4·2N2H4, were synthesized via a facile solution synthesis approach based on the solid-liquid reaction between NaBH4 and hydrazine in tetrahydrofuran (THF) solution. The crystal structure of NaBH4·2N2H4 was solved to a monoclinic structure with unit cell parameters a = 8.4592(2) Å, b = 11.7131(2) Å, c = 6.4584(1) Å, and β = 100.0777(14)°, with space group A1a1 (9). Each …


Effect Of Extreme Pressure Additives On The Deformation Behavior Of Oxide Scale During The Hot Rolling Of Ferritic Stainless Steel Strips, Liang Hao, Zhengyi Jiang, Xiawei Cheng, Jingwei Zhao, Dongbin Wei, Laizhu Jiang, Suzhen Luo, Ming Luo, Li Ma Jan 2015

Effect Of Extreme Pressure Additives On The Deformation Behavior Of Oxide Scale During The Hot Rolling Of Ferritic Stainless Steel Strips, Liang Hao, Zhengyi Jiang, Xiawei Cheng, Jingwei Zhao, Dongbin Wei, Laizhu Jiang, Suzhen Luo, Ming Luo, Li Ma

Faculty of Engineering and Information Sciences - Papers: Part A

High-speed steel (HSS) materials are universally used as work rolls for the hot rolling of stainless steels. Their use has increased the output of the rolling mill and decreased roll material consumption and grinding. Sticking defects often occur, however, during the hot rolling process. In this article, extreme pressure (EP) additives were dropped on the HSS samples at high temperature. Zinc dialkyl dithiophosphate (ZDDP) was chosen as the most effective EP additive by scratch tests on the HSS samples. In order to determine the optimum proportion of ZDDP in the lubricant, two reduction rates were tested on a Hille 100 …


Ray Optics Behavior Of Flux Avalanche Propagation In Superconducting Films, Pavlo Mikheenko, Tom H. Johansen, Supratim Chaudhuri, I J. Maasilta, Y Galperin Jan 2015

Ray Optics Behavior Of Flux Avalanche Propagation In Superconducting Films, Pavlo Mikheenko, Tom H. Johansen, Supratim Chaudhuri, I J. Maasilta, Y Galperin

Australian Institute for Innovative Materials - Papers

Experimental evidence of wave properties of dendritic flux avalanches in superconducting films is reported. Using magneto-optical imaging the propagation of dendrites across boundaries between a bare NbN film and areas coated by a Cu layer was visualized, and it was found that the propagation is refracted in full quantitative agreement with Snell's law. For the studied film of 170 nm thickness and a 0.9μm thick metal layer, the refractive index was close to n=1.4. The origin of the refraction is believed to be caused by the dendrites propagating as an electromagnetic shock wave, similar to damped modes …


Crowd Behavior Recognition Using Dense Trajectories, Muhammad Rizwan Khokher, Abdesselam Bouzerdoum, Son Lam Phung Jan 2014

Crowd Behavior Recognition Using Dense Trajectories, Muhammad Rizwan Khokher, Abdesselam Bouzerdoum, Son Lam Phung

Faculty of Engineering and Information Sciences - Papers: Part A

This article presents a new method for crowd behavior recognition, using dynamic features extracted from dense trajectories. The histogram of oriented gradient and motion boundary histogram descriptors are computed at dense points along motion trajectories, and tracked using median filtering and displacement information obtained from a dense optical flow field. Then a global representation of the scene is obtained using a bag-of-words model of the extracted features. The locality-constrained linear encoding with sum pooling and L2 plus power normalization are employed in the bag-of-words model. Finally, a support vector machine classifier is trained to recognize the crowd behavior in a …


Study On Hot-Working Behavior Of High Carbon Steel / Low Carbon Steel Composite Material Using Processing Map, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Sihai Jiao, Dengfu Chen Jan 2014

Study On Hot-Working Behavior Of High Carbon Steel / Low Carbon Steel Composite Material Using Processing Map, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Sihai Jiao, Dengfu Chen

Faculty of Engineering and Information Sciences - Papers: Part A

The high carbon steel (HCS)/low carbon steel (LCS) laminated composite made by centrifugal casting technology was subjected to hot compression tests on Gleeble 3500 thermomechanical simulator in a range of temperatures (800-1100 oC) and strain rates (0.02-10 s-1). The hot-working behavior of the laminate was characterised by analysing the flow stress-strain curves and constructing the processing map based on dynamic materials model via superimposing efficiency of power dissipation and flow instability maps. The safe and unsafe processing conditions were identified in the processing map which was validated by microstructural examinations. Banded microstructure and micro-shear cracks occurred in the unsafe domains …


A Study Of Plastic Deformation Behavior During High Pressure Torsion Process By Crystal Plasticity Finite Element Simulation, Peitang Wei, Cheng Lu, A K. Tieu, Guanyu Deng Jan 2014

A Study Of Plastic Deformation Behavior During High Pressure Torsion Process By Crystal Plasticity Finite Element Simulation, Peitang Wei, Cheng Lu, A K. Tieu, Guanyu Deng

Faculty of Engineering and Information Sciences - Papers: Part A

High pressure torsion (HPT) is an efficient technique of producing ultrafine grained materials with exceptional small grain size. In this study, a crystal plasticity finite element method (CPFEM) model has been developed to investigate the plastic deformation behavior of pure aluminum single crystal during the HPT process. The simulation results show that, the distribution and evolution of the macroscopic plastic strain and the accumulative shear strain are similar. The value increases with the increase of the distance from the center as well as the number of revolution. The simulation is capable of reflecting the anisotropic characteristics of HPT deformation, a …


Atomistic Simulation Of Tensile Deformation Behavior Of Σ5 Tilt Grain Boundaries In Copper Bicrystal, Liang Zhang, Cheng Lu, A Kiet Tieu Jan 2014

Atomistic Simulation Of Tensile Deformation Behavior Of Σ5 Tilt Grain Boundaries In Copper Bicrystal, Liang Zhang, Cheng Lu, A Kiet Tieu

Faculty of Engineering and Information Sciences - Papers: Part A

Experiments on polycrystalline metallic samples have indicated that Grain boundary (GB) structure can affect many material properties related to fracture and plasticity. In this study, atomistic simulations are employed to investigate the structures and mechanical behavior of both symmetric and asymmetric ∑5[0 0 1] tilt GBs of copper bicrystal. First, the equilibrium GB structures are generated by molecular statics simulation at 0K. The results show that the ∑5 asymmetric GBs with different inclination angles (φ) are composed of only two structural units corresponding to the two ∑5 symmetric GBs. Molecular dynamics simulations are then conducted to investigate the mechanical response …


Platinum Dendritic Nanoparticles With Magnetic Behavior, Wenxian Li, Ziqi Sun, Dongliang Tian, Ivan P. Nevirkovets, S X. Dou Jan 2014

Platinum Dendritic Nanoparticles With Magnetic Behavior, Wenxian Li, Ziqi Sun, Dongliang Tian, Ivan P. Nevirkovets, S X. Dou

Australian Institute for Innovative Materials - Papers

Magnetic nanoparticles have attracted increasing attention for biomedical applications in magnetic resonance imaging, high frequency magnetic field hyperthermia therapies, and magnetic-field-gradient-targeted drug delivery. In this study, three-dimensional (3D) platinum nanostructures with large surface area that features magnetic behavior have been demonstrated. The well-developed 3D nanodendrites consist of plentiful interconnected nano-arms ∼4 nm in size. The magnetic behavior of the 3D dendritic Pt nanoparticles is contributed by the localization of surface electrons due to strongly bonded oxygen/Pluronic F127 and the local magnetic moment induced by oxygen vacancies on the neighboring Pt and O atoms. The magnetization of the nanoparticles exhibits a …


Capacitive Behavior Of Latex/Single-Wall Carbon Nanotube Stretchable Electrodes, Hyeon Taek Jeong, Byung Kim, Robert Gorkin Iii, Michael J. Higgins, Gordon G. Wallace Jan 2014

Capacitive Behavior Of Latex/Single-Wall Carbon Nanotube Stretchable Electrodes, Hyeon Taek Jeong, Byung Kim, Robert Gorkin Iii, Michael J. Higgins, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

In this report single-wall carbon nanotubes (SWNTs) were coated onto latex using spray coating to produce a stretchable electrode. The electrochemical properties of the electrode were determined using cyclic voltammetry and electrochemical impedance spectroscopy and galvanostatic charge/discharge tests were also carried out. The impedance and charge/discharge curves of the latex/SWNTs electrode showed good capacitive behavior even after repetitive stretching to 100% strain. The highest capacitance value obtained for the unstretched SWNTs electrode was 119 F g−1 in 1 M Na2SO4 at 5 mV s−1. After the 100th stretch ≈ 80% of the original capacitance value was retained.


Tunable Negative Permittivity Behavior And Conductor-Insulator Transition In Dual Composites Prepared By Selective Reduction Reaction, Zi-Dong Zhang, Run-Hua Fan, Zhi-Cheng Shi, Shi-Bing Pan, Ke-Lan Yan, Kang-Ning Sun, Jing-De Zhang, Xiang-Fa Liu, Xiaolin Wang, S X. Dou Jan 2013

Tunable Negative Permittivity Behavior And Conductor-Insulator Transition In Dual Composites Prepared By Selective Reduction Reaction, Zi-Dong Zhang, Run-Hua Fan, Zhi-Cheng Shi, Shi-Bing Pan, Ke-Lan Yan, Kang-Ning Sun, Jing-De Zhang, Xiang-Fa Liu, Xiaolin Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

We use a selective reduction reaction to fabricate a new kind of dual composite, which has a "composite-within-a-composite" structure. Based on the different reduction behavior of Fe2O3, an Fe-rich structure (Fe-Fe3O4-Al2O3) is formed in an Al-rich structure (FeAl2O4-Al2O3). The Fe-rich structure can bring down the concentration of free electrons to reduce the energy loss, without losing its metallic behaviour at the same time. Near the percolation threshold, a conductor-insulator transition appears and the dual composites show totally different electromagnetic responses, which can be well explained by effective medium theory. By controlling the parameters of the selective reduction process, we can …


Trace Elements In The Si Furnace. Part I: Behavior Of Impurities In Quartz During Reduction, Elena Dal Martello, Gabriella Tranell, Oleg Ostrovski, Guangqing Zhang, Ola Raaness, Rune Burg Larsen, Kai Tang, Pramod Koshy Jan 2013

Trace Elements In The Si Furnace. Part I: Behavior Of Impurities In Quartz During Reduction, Elena Dal Martello, Gabriella Tranell, Oleg Ostrovski, Guangqing Zhang, Ola Raaness, Rune Burg Larsen, Kai Tang, Pramod Koshy

Faculty of Engineering and Information Sciences - Papers: Part A

Quartz and carbonaceous materials, which are used in the production of silicon as well as electrodes and refractories in the silicon furnace, contain trace elements mostly in the form of oxides. These oxides can be reduced to gaseous compounds and leave the furnace or stay in the reaction products—metal and slag. This article examines the behavior of trace elements in hydrothermal quartz and quartzite in the reaction of SiO2 with Si or SiC. Mixtures of SiO2 (quartz or quartzite), SiC, and Si in forms of lumps or pellets were heated to 1923 K and 2123 K (1650°C and 1850°C) in …


Microtexture Based Analysis Of Surface Asperity Flattening Behavior Of Annealed Aluminum Alloy In Uniaxial Planar Compression, Hejie Li, Zhengyi Jiang, Dongbin Wei, Xiaoming Zhang Jan 2013

Microtexture Based Analysis Of Surface Asperity Flattening Behavior Of Annealed Aluminum Alloy In Uniaxial Planar Compression, Hejie Li, Zhengyi Jiang, Dongbin Wei, Xiaoming Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

During the uniaxial planar compression of annealed aluminum alloy, a novel approach to determine surface asperity flattening (roughness Ra) is employed by analyzing the evolution of surface microtexture. With an increase in gauged reduction, surface asperity tends to be flattened, and strain hardening increases. Lubrication can constrain the surface asperity flattening process. Development of surface asperity features shows the obvious dependency on [111] orientation. In-grain slips contribute significantly to the evolution of surface microtexture. Influence of deformation twins (brass orientation) on the evolution of microtexture is not obvious under our current experimental conditions.


Modeling And Experimental Investigation On The Mechanical Behavior Of A Spiral-Type Capsule In The Small Intestine, Hao Zhou, Gursel Alici, Trung Duc Than, Weihua Li Jan 2013

Modeling And Experimental Investigation On The Mechanical Behavior Of A Spiral-Type Capsule In The Small Intestine, Hao Zhou, Gursel Alici, Trung Duc Than, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part A

This paper reports on the study of the behavior of the viscoelastic contact between a spiral-type capsule and the small intestine. Both 2D and 3D simulations show that the traction force, which is due to the pressure difference between the two sides of the spirals, is velocity dependent. With an increase in the sliding velocity, the traction force decreases initially due to the reduced stress relaxation. However, if the velocity reaches some certain magnitude, the reduction in the stress becomes negligibly small. The traction force starts to increase because of the higher stress coming from the higher strain rates. The …


Modeling The Internal Erosion Behavior Of Lignosulfonate Treated Soil, Rasika Athukorala, Buddhima Indraratna, Jayan S. Vinod Jan 2013

Modeling The Internal Erosion Behavior Of Lignosulfonate Treated Soil, Rasika Athukorala, Buddhima Indraratna, Jayan S. Vinod

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents the development of an analytical model to predict the erosion rate of stabilised soil based on the law of conservation of energy. The model incorporates the strain energy intensity until failure, obtained from the stress-strain curves of lignosulfonate treated soil, to account for the stabilisation. The novel approach of this model is to correlate the shear strength characteristics with the erosion resistance. The proposed equation was used to predict the erosion rates of a non-plastic silty sand treated with lignosulfonate. The erosion resistance was interpreted in terms of the coefficient of soil erosion and the critical shear …