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Full-Text Articles in Engineering
Effect Of Tensile Load On The Actuation Performance Of Ph-Sensitive Hydrogels, Sina Naficy, Geoffrey M. Spinks
Effect Of Tensile Load On The Actuation Performance Of Ph-Sensitive Hydrogels, Sina Naficy, Geoffrey M. Spinks
Australian Institute for Innovative Materials - Papers
pH-responsive hydrogels are capable of converting chemical energy to mechanical work. To optimize their use as actuators, their response when operating against an external load must be fully characterized. Here, the actuation strain of a model pH-sensitive hydrogel as a function of different constant loads is studied. The experimental actuation strain, produced by switching the pH from 2 to 12, decreases significantly and monotonically with increasing initial tensile load. Two models are developed to predict the actuation strain as a function of applied stress. Simple mechanical models based on the change in hydrogel modulus and cross sectional area due to …
Magnetocaloric Effect And Magnetostructural Coupling In Mn0.92fe0.08coge Compound, Jianli Wang, Precious Shamba, Wayne D. Hutchison, Qinfen Gu, M F. Md Din, Q Y. Ren, Zhenxiang Cheng, Shane J. Kennedy, Stewart J. Campbell, S X. Dou
Magnetocaloric Effect And Magnetostructural Coupling In Mn0.92fe0.08coge Compound, Jianli Wang, Precious Shamba, Wayne D. Hutchison, Qinfen Gu, M F. Md Din, Q Y. Ren, Zhenxiang Cheng, Shane J. Kennedy, Stewart J. Campbell, S X. Dou
Australian Institute for Innovative Materials - Papers
The structural properties of Mn0.92Fe0.08CoGe have been investigated in detail using synchrotron x-ray diffraction in zero and applied pressure (p = 0-10 GPa). A ferromagnetic transition occurs around TC = 300 K and a large magnetic-entropy change −ΔSM = 17.3 J/kg K detected at TC for a field change of ΔB = 5 T. The field dependence of −ΔS M max can be expressed as −ΔS M max ∝ B. At ambient temperature and pressure, Mn0.92Fe0.08CoGe exhibits a co-existence of the orthorhombic TiNiSi-type structure (space group Pnma) and hexagonal …
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
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 …
Improved Correction For The Tissue Fraction Effect In Lung Pet/Ct Imaging, Beverley F. Holman, Vesna Cuplov, Lynn Millner, Brian F. Hutton, Toby M. Maher, Ashley M. Groves, Kris Thielemans
Improved Correction For The Tissue Fraction Effect In Lung Pet/Ct Imaging, Beverley F. Holman, Vesna Cuplov, Lynn Millner, Brian F. Hutton, Toby M. Maher, Ashley M. Groves, Kris Thielemans
Faculty of Engineering and Information Sciences - Papers: Part A
Recently, there has been an increased interest in imaging different pulmonary disorders using PET techniques. Previous work has shown, for static PET/CT, that air content in the lung influences reconstructed image values and that it is vital to correct for this 'tissue fraction effect' (TFE). In this paper, we extend this work to include the blood component and also investigate the TFE in dynamic imaging. CT imaging and PET kinetic modelling are used to determine fractional air and blood voxel volumes in six patients with idiopathic pulmonary fibrosis. These values are used to illustrate best and worst case scenarios when …
Effect Of Temperature On Microstructure And Deformation Mechanism Of Fe-30mn-3si-4al Twip Steel At Strain Rate Of 700 S-1, Zhiping Xiong, Xue-Ping Ren, Jian Shu, Zhe-Lei Wang, Wei-Ping Bao, Shu-Xia Li
Effect Of Temperature On Microstructure And Deformation Mechanism Of Fe-30mn-3si-4al Twip Steel At Strain Rate Of 700 S-1, Zhiping Xiong, Xue-Ping Ren, Jian Shu, Zhe-Lei Wang, Wei-Ping Bao, Shu-Xia Li
Faculty of Engineering and Information Sciences - Papers: Part A
As twinning-induced plasticity (TWIP) steel is one potential material for shaped charge liner due to the combination of high strength and high plasticity, deformation mechanism at high strain rate and high temperature is required to study. Compression experiments of Fe-30Mn-3Si-4Al TWIP steel were conducted using a Gleeble-1500 thermal simulation machine and a split-Hopkinson pressure bar (SHPB) between 298 and 1073 K at strain rates of 10-3 and 700 s-1, respectively. Microstructures were observed using optical microscopy (OM) and transmission electron microscopy (TEM). Results show that flow stress and densities of deformation twins and dislocations decrease with increasing deformation temperature at …
Grain Size Effect Of Thickness/Average Grain Size On Mechanical Behaviour, Fracture Mechanism And Constitutive Model For Phosphor Bronze Foil, Zhi Fang, Zhengyi Jiang, Xiaogang Wang, Cunlong Zhou, Dongbin Wei, Xianghua Liu
Grain Size Effect Of Thickness/Average Grain Size On Mechanical Behaviour, Fracture Mechanism And Constitutive Model For Phosphor Bronze Foil, Zhi Fang, Zhengyi Jiang, Xiaogang Wang, Cunlong Zhou, Dongbin Wei, Xianghua Liu
Faculty of Engineering and Information Sciences - Papers: Part A
Size effects play a significant role in microforming process, and any dimensional change can have a great impact on materials' mechanical properties. In this paper, the size effects on deformation behaviour and fracture of phosphor foil were investigated in the form of grain size effect: the ratio of materials' thickness (T) to average grain size (D) by micro tensile tests. The ratio was designed to be closed to but larger than, less than and equal to 1, respectively. The results show that the amount of plastic deformation decreases with the decrease of the ratio of T/D, which indicates that the …
The Bulk-Edge Correspondence For The Quantum Hall Effect In Kasparov Theory, Christopher J. Bourne, Alan L. Carey, Adam C. Rennie
The Bulk-Edge Correspondence For The Quantum Hall Effect In Kasparov Theory, Christopher J. Bourne, Alan L. Carey, Adam C. Rennie
Faculty of Engineering and Information Sciences - Papers: Part A
We prove the bulk-edge correspondence in K-theory for the quantum Hall effect by constructing an unbounded Kasparov module from a short exact sequence that links the bulk and boundary algebras. This approach allows us to represent bulk topological invariants explicitly as a Kasparov product of boundary invariants with the extension class linking the algebras. This paper focuses on the example of the discrete integer quantum Hall effect, though our general method potentially has much wider applications.
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
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 …
The Effect Of Geometry And Material Properties On The Performance Of A Small Hydraulic Mckibben Muscle System, Danial Sangian, Sina Naficy, Geoffrey M. Spinks, Bertrand Tondu
The Effect Of Geometry And Material Properties On The Performance Of A Small Hydraulic Mckibben Muscle System, Danial Sangian, Sina Naficy, Geoffrey M. Spinks, Bertrand Tondu
Faculty of Engineering and Information Sciences - Papers: Part A
Fluidic McKibben artificial muscles are one of the most popular biomimetic actuators, showing similar static and dynamic performance to skeletal muscles. In particular, their pneumatic version offers high-generated force, high speed and high strain in comparison to other actuators. This paper investigates the development of a small-size, fully enclosed, hydraulic McKibben muscle powered by a low voltage pump. Hydraulic McKibben muscles with an outside diameter of 6 mm and a length ranging from 35 mm to 80 mm were investigated. These muscles are able to generate forces up to 26 N, strains up to 23%, power to mass of 30 …
The Effect Of Nb On The Continuous Cooling Transformation Curves Of Ultra-Thin Strip Castrip© Steels, Kristin R. Carpenter, Chris R. Killmore
The Effect Of Nb On The Continuous Cooling Transformation Curves Of Ultra-Thin Strip Castrip© Steels, Kristin R. Carpenter, Chris R. Killmore
Faculty of Engineering and Information Sciences - Papers: Part A
The effect of Nb on the hardenability of ultra-thin cast strip (UCS) steels produced via the unique regime of rapid solidification, large austenite grain size, and inclusion engineering of the CASTRIP© process was investigated. Continuous cooling transformation (CCT) diagrams were constructed for 0, 0.014, 0.024, 0.04, 0.06 and 0.08 wt% Nb containing UCS steels. Phase nomenclature for the identification of lower transformation product in low carbon steels was reviewed. Even a small addition of 0.014 wt% Nb showed a potent effect on hardenability, shifting the ferrite C-curve to the right and expanding the bainitic ferrite and acicular ferrite phase …
Effect Of Mesh On Springback In 3d Finite Element Analysis Of Flexible Microrolling, Feijun Qu, Zhengyi Jiang, Haina Lu
Effect Of Mesh On Springback In 3d Finite Element Analysis Of Flexible Microrolling, Feijun Qu, Zhengyi Jiang, Haina Lu
Faculty of Engineering and Information Sciences - Papers: Part A
In flexible microrolling, springback in thickness direction is a critical indicator to determine the forming quality. Accurate prediction of springback is one of the significant aspects in the finite element analysis of flexible microrolling. Meshing is a step of great importance in finite element analysis of manufacturing process as it directly determines the accuracy of the FEA results as well as the requested computational time. This paper presents a numerical study on revealing the mesh effects on the accuracy of springback estimation utilising ABAQUS/Standard for modelling and analyses. Two types of meshes with six mesh sizes for each mesh type …
Effect Of Pre-Quenching Process On Microstructure And Mechanical Properties In A Nb-Microalloyed Low Carbon Q-P Steel, Jun Zhang, Hua Ding, Jingwei Zhao
Effect Of Pre-Quenching Process On Microstructure And Mechanical Properties In A Nb-Microalloyed Low Carbon Q-P Steel, Jun Zhang, Hua Ding, Jingwei Zhao
Faculty of Engineering and Information Sciences - Papers: Part A
A refined microstructure consisting of martensite and retained austenite at room temperature has been produced in a Nb-microalloyed low carbon Si-Mn steel by a novel heat-treatment, pre-quenching prior to quenching and partitioning processes (Q&Q-P). The results showed that compared with the conventional quenching and partitioning steel the mechanical properties of steel obtained by the novel treatment have been significantly improved, with a good combination of ultimate tensile strength (1000MPa) and total elongation (above 30%). Meanwhile, the volume fraction of retained austenite has been increased. It was found that the improvement of mechanical properties was mainly attributed to the enhanced TRIP …
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
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 …
The Effect Of Surface Passivation On The Structure Of Sulphur-Rich Pbs Colloidal Quantum Dots For Photovoltaic Application, Victor Malgras, Andrew Nattestad, Yusuke Yamauchi, S X. Dou, Jung Ho Kim
The Effect Of Surface Passivation On The Structure Of Sulphur-Rich Pbs Colloidal Quantum Dots For Photovoltaic Application, Victor Malgras, Andrew Nattestad, Yusuke Yamauchi, S X. Dou, Jung Ho Kim
Australian Institute for Innovative Materials - Papers
The use of PbS colloidal quantum dots in photovoltaic devices is very promising because of their simple and low cost production processes and their unique properties, such as bandgap tunability and potential multiple exciton generation. Here we report the synthesis of PbS nanocrystals used for application in solar cells. The sulphur-rich nature of their surface appears to be caused by the exposure to ambient conditions. The use of methanol as medium during the ligand exchange process has a crucial role in the removal of native oleate ligands. Without proper ligand exchange, the unpassivated surface is subject to ambient hydroxylation leading …
Pauli-Limited Effect In The Magnetic Phase Diagram Of Fesexte1−X Thin Films, Jincheng Zhuang, Zhen Li, Xun Xu, Li Wang, Wai Kong Yeoh, X Z. Xing, Zhixiang Shi, Xiaolin Wang, Yi Du, S X. Dou
Pauli-Limited Effect In The Magnetic Phase Diagram Of Fesexte1−X Thin Films, Jincheng Zhuang, Zhen Li, Xun Xu, Li Wang, Wai Kong Yeoh, X Z. Xing, Zhixiang Shi, Xiaolin Wang, Yi Du, S X. Dou
Australian Institute for Innovative Materials - Papers
We present a detailed investigation on the doping dependence of the upper critical fieldHc2(T) of FeSexTe1−xthin films (0.18 ≤ x ≤ 0.90) by measuring the electrical resistivity as a function of magnetic field. The Hc2(T) curves exhibit a downturn behavior with decreasing temperature in all the samples, owing to the Pauli-limited effect (spin paramagnetic effect). The Pauli-limited effect on the upper critical field can be monotonically modulated by variation of the Se/Te composition. Our results show that Te-doping induced disorder and excess Fe atoms give rise to enhancement of the Pauli-limited effect.