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Physical Sciences and Mathematics

University of Wollongong

2015

Effect

Articles 1 - 6 of 6

Full-Text Articles in Engineering

Effect Of Tensile Load On The Actuation Performance Of Ph-Sensitive Hydrogels, Sina Naficy, Geoffrey M. Spinks Jan 2015

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 …


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 Jan 2015

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 Jan 2015

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.


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 …


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 Jan 2015

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 …


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 …