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Full-Text Articles in Engineering
Structure, Ferroelectric Properties, And Magnetic Properties Of The La-Doped Bismuth Ferrite, Zhenxiang Cheng, Aihua Li, Xiaolin Wang, S X. Dou, Kiyoshi Ozawa, Hideo Kimura, S Zhang, Thomas R. Shrout
Structure, Ferroelectric Properties, And Magnetic Properties Of The La-Doped Bismuth Ferrite, Zhenxiang Cheng, Aihua Li, Xiaolin Wang, S X. Dou, Kiyoshi Ozawa, Hideo Kimura, S Zhang, Thomas R. Shrout
Australian Institute for Innovative Materials - Papers
Bi1-xLaxFeO3 ceramics with x=0, 0.1, 0.2, and 0.3 have been synthesized by solid state reaction, starting from metal oxides. A series of structure transformations is found to depend upon the doping level. Below 10% La doping, Bi1-xLaxFeO3 maintains the rhombohedral structure of BiFeO3. However, for Bi0.8La0.2FeO3 and Bi0.7La0.3FeO3, the structures change to the orthorhombic and tetragonal, respectively. La doping significantly reduces electric leakage and leads to successful observation of electrical polarization hysteresis loops. Doping with La also …
Improved Ferroelectric Properties In Multiferroic Bifeo3 Thin Films Through La And Nb Codoping, Zhenxiang Cheng, Xiaolin Wang, S X. Dou, Hideo Kimura, Kiyoshi Ozawa
Improved Ferroelectric Properties In Multiferroic Bifeo3 Thin Films Through La And Nb Codoping, Zhenxiang Cheng, Xiaolin Wang, S X. Dou, Hideo Kimura, Kiyoshi Ozawa
Australian Institute for Innovative Materials - Papers
We report the significant improvement of the ferroelectric properties of BiFeO3thin film through control of electrical leakage by Nb doping. A very large remanent electrical polarization value of 80 µC/cm2 was observed in Bi0.8La0.2Nb0.01Fe0.99O3 thin film on Pt/Ti/SiO2/Si substrate. The doping effect of Nb in reducing the movable charge density due to oxygen vacancies in BiFeO3 was confirmed by the dielectric measurements. A very small loss was observed in the Nb and La codoped BiFeO3 thin film. As well as the improvement in the …
Magnetotransport And Magnetic Properties Of Weak Ferromagnetic Semiconductors: Ca Doped Lacro3, Gustavo A. Alvarez, Xiaolin Wang, Germanas Peleckis, S. X. Dou, Jian G. Zhu, Zhi W. Lin
Magnetotransport And Magnetic Properties Of Weak Ferromagnetic Semiconductors: Ca Doped Lacro3, Gustavo A. Alvarez, Xiaolin Wang, Germanas Peleckis, S. X. Dou, Jian G. Zhu, Zhi W. Lin
Faculty of Engineering - Papers (Archive)
We report the magnetic and magnetotransport properties of Ca doped La1-xCaxCrO3 (x=0, 0.1, 0.2, and 0.3). Both the magnetic and transport properties are very sensitive to Ca substitution. The Neel temperature T-N decreases substantially with increasing calcium doping concentration from 290 to 160 K. A weak ferromagnetic state with large coercive fields of up to 3 T is present for the Ca doped LaCrO3. The temperature dependence of the resistivity shows that all the Ca doped com#163s are semiconducting and their resistivities decrease with increasing Ca for low doping levels. The resistivity curves show thermally activated behavior and a variable …
Effects Of Sintering Atmosphere On The Superconducting Properties Of Sic Doped Bulk Mgb2 Superconductor, Sihai Zhou, Alexey V. Pan, Yun Zhang, S. X. Dou
Effects Of Sintering Atmosphere On The Superconducting Properties Of Sic Doped Bulk Mgb2 Superconductor, Sihai Zhou, Alexey V. Pan, Yun Zhang, S. X. Dou
Faculty of Engineering - Papers (Archive)
A study was conducted to investigate the effects of the sintering atmosphere on the superconducting properties of SiC doped MgB2 superconductors. Four different purity Ar gases were chosen as the sintering atmosphere for making bulk samples. It was found that the impurities in the Ar gas resulted in different leves of MgO in the resultant MgB2 superconductors. Superconducting properties, such as the critical temperature (Tc), critical current density (Jc) and upper critical field (Hc2) were affected by the impurity phase inside the samples. Sample phase composition and morphology were analysed to explain the effect of the sintering atmosphere on the …
Shape Evolution Of Α-Fe2o3 And Its Size-Dependent Electrochemical Properties For Lithium-Ion Batteries, Yanna Nuli, Peng Zhang, Zaiping Guo, Hua-Kun Liu
Shape Evolution Of Α-Fe2o3 And Its Size-Dependent Electrochemical Properties For Lithium-Ion Batteries, Yanna Nuli, Peng Zhang, Zaiping Guo, Hua-Kun Liu
Faculty of Engineering - Papers (Archive)
Crystalline α-Fe2O3 with different particle shapes and sizes was selectively synthesized by a simple hydrothermal method. By carefully tuning the concentration of the reactants and the reaction time, α-Fe2O3 cuboid particles and nanowires can be obtained. Based on the evidence of electron microscope images, a shape evolution mechanism for the nanowire structure is proposed. Electrochemical performance as an anode material for lithium-ion batteries was further evaluated by cyclic voltammetry, electrochemical impedance, and charge–discharge measurements. It was demonstrated that both the morphology and the particle size had an influence on the performance. Compared with the electrode made from the …
Dielectric, Magnetic, And Magnetotransport Properties In Sr Doped Two-Dimensional Re2coo4 (Re=Pr,Eu) Compounds, Qiwen Yao, Xiaolin Wang, S X. Dou
Dielectric, Magnetic, And Magnetotransport Properties In Sr Doped Two-Dimensional Re2coo4 (Re=Pr,Eu) Compounds, Qiwen Yao, Xiaolin Wang, S X. Dou
Australian Institute for Innovative Materials - Papers
In this work, we report on the studies of dielectric, magnetic, and magnetotransport properties of Sr doped RE2-xSrxCoO4 (RE=Pr or Eu, x=0.25-1.5). These compounds were systematically studied in terms of structure, magnetic, magnetotransport, and dielectric constant measurements. Rietveld refinement indicated that these compounds crystallized in K2NiF4-type structure with space group I4/mmm. Lattice parameters increase with Sr doping level. The system changes from paramagnetic to ferromagnetic with increasing Sr doping level and finally becomes ferromagnetic with TC of 230 K for Pr0.75Sr1.25CoO4 and …
Phase Transformation And Superconducting Properties Of Mgb2 Using Ball-Milled Low Purity Boron, Xun Xu, Jung Ho Kim, Md. Shahriar-Al Hossain, Jinsoo Park, Yue Zhao, S. X. Dou, Wai Kong Yeoh, M Rindfleisch, M Tomsic
Phase Transformation And Superconducting Properties Of Mgb2 Using Ball-Milled Low Purity Boron, Xun Xu, Jung Ho Kim, Md. Shahriar-Al Hossain, Jinsoo Park, Yue Zhao, S. X. Dou, Wai Kong Yeoh, M Rindfleisch, M Tomsic
Faculty of Engineering - Papers (Archive)
MgB2 samples were prepared by using 96% boron (B) powder with strong crystalline phase that had been ball milled for various times. We observed samples that contained ball-milled 96% B in comparison with one made from as-supplied commercial 96% B, with the results showing a significant enhancement in the high field critical current density (Jc) due to small grain size and better reactivity. Specifically, many grain boundaries for MgB2 could be acting as strong flux pinning centers. Based on Rowell connectivity analysis, when the ball-milling time increased, the connectivity factor, described as the active cross-sectional …
An Alternative Rail Pad Tester For Measuring Dynamic Properties Of Rail Pads Under Large Preloads, Sakdirat Kaewunruen, Alexander Remennikov
An Alternative Rail Pad Tester For Measuring Dynamic Properties Of Rail Pads Under Large Preloads, Sakdirat Kaewunruen, Alexander Remennikov
Faculty of Engineering - Papers (Archive)
One of the main components in ballasted railway track systems is the rail pad. It is installed between the rail and the sleeper to attenuate wheel/rail interaction loads, preventing the underlying railway sleepers from excessive stress waves. Generally, the dynamic design of tracks relies on the available data, which are mostly focused on the structural condition at a specific toe load. Recent findings show that track irregularities could significantly amplify the loads on railway tracks. This phenomenon gives rise to a concern that the rail pads may experience higher effective preloading than anticipated in the past. On this ground, this …
Correlation Between Doping Induced Disorder And Superconducting Properties In Carbohydrate Doped Mgb2, Jung Ho Kim, S X. Dou, Sangjun Oh, M Jercinovic, E Babic, T Nakane, Hiroaki Kumakura
Correlation Between Doping Induced Disorder And Superconducting Properties In Carbohydrate Doped Mgb2, Jung Ho Kim, S X. Dou, Sangjun Oh, M Jercinovic, E Babic, T Nakane, Hiroaki Kumakura
Australian Institute for Innovative Materials - Papers
A comprehensive study of the effects of carbohydrate doping on the superconductivity of MgB2 has been conducted. In accordance with the dual reaction model, more carbon substitution is achieved at lower sintering temperature. As the sintering temperature is lowered, lattice disorder is increased. Disorder is an important factor determining the transition temperature for the samples studied in this work, as evidenced from the correlations among the lattice strain, the resistivity, and the transition temperature. It is further shown that the increased critical current density in the high field region can be understood by a recently-proposed percolation model [M. Eisterer …