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Full-Text Articles in Engineering
Effects Of Initial Static Shear On Liquefaction And Large Deformation Properties Of Loose Saturated Toyoura Sand In Undrained Cyclic Torsional Shear Tests, Gabriele Chiaro, Junichi Koseki, Takeshi Sato
Effects Of Initial Static Shear On Liquefaction And Large Deformation Properties Of Loose Saturated Toyoura Sand In Undrained Cyclic Torsional Shear Tests, Gabriele Chiaro, Junichi Koseki, Takeshi Sato
Faculty of Engineering - Papers (Archive)
This study focused on the role which static shear plays on the large deformation behavior of loose saturated sand during undrained cyclic loading. A series of undrained cyclic torsional shear tests was performed on saturated Toyoura sand specimens up to single amplitude shear strain exceeding 50%. Three types of cyclic loading patterns, i.e., stress reversal, intermediate and non-reversal, were employed by varying the initial static shear level and the cyclic shear stress amplitude. The observed types of failure could be distinguished into liquefaction (cyclic and rapid flow) and residual deformation by comparing both monotonic and cyclic undrained behavior. It was …
Effect Of Annealing On The Microstructure, Texture And Mechanical Properties Of Severely Deformed Interstitial Free Steel, Sujoy S. Hazra, Azdiar A. Gazder, E V. Pereloma
Effect Of Annealing On The Microstructure, Texture And Mechanical Properties Of Severely Deformed Interstitial Free Steel, Sujoy S. Hazra, Azdiar A. Gazder, E V. Pereloma
Faculty of Engineering - Papers (Archive)
Ti-stabilised interstitial free (IF) steel initially subjected to 8 passes, route BC equal channel angular pressing (ECAP) was further cold rolled (CR) at room temperature to 95% thickness reduction. Both samples were isothermally annealed at 710 °C following which their microstructures and micro-textures were compared via electron back-scattering diffraction (EBSD). The mechanical properties first obtained by shear punch testing (SPT) were later corroborated by uniaxial tensile tests. In the case of the ECAP material, continuous recrystallisation is followed by abnormal growth at prolonged annealing times with minor increases in high angle boundary (HAGB) fraction. On the other hand, the …
"Density Of States, Magnetic And Transport Properties Of Nd Doped Two Dimensional Perovskite Compound Sr2coo4", Qiwen Yao, Hideo Kimura, Xiaolin Wang, Kosta Konstantinov, Hongyang Zhao, Hai Qiu, Rumi Tanahashi, Kiyoshi Ozawa, S. X. Dou
"Density Of States, Magnetic And Transport Properties Of Nd Doped Two Dimensional Perovskite Compound Sr2coo4", Qiwen Yao, Hideo Kimura, Xiaolin Wang, Kosta Konstantinov, Hongyang Zhao, Hai Qiu, Rumi Tanahashi, Kiyoshi Ozawa, S. X. Dou
Faculty of Engineering - Papers (Archive)
"Structures, transport, magnetic properties, and first principle calculation results will be reported for the two dimensional layered structured perovskite compounds Sr2-xNdxCoO4 (x = 0.5, 0.75, 1, 1.25). Structure refinement results revealed that these compounds crystallized in K2NiF4-type structures with space group I4/mmm. The temperature dependence of resistivity showed semiconductor like behavior for these samples. It was found that the lattice parameter c decreases as the doping level x increases. The compounds exhibited a paramagnetic to ferromagnetic transition at temperatures of about 170, 125 K for the x = 1 and 0.75 samples, respectively. The temperature dependence of resistivity for the …
Growth Mechanism And Magnetic Properties Of Highly Crystalline Nio Nanocubes And Nanorods Fabricated By Evaporation, Dapeng Chen, Xiaolin Wang, Yi Du, Song Ni, Zi-Bin Chen, Xiaozhou Liao
Growth Mechanism And Magnetic Properties Of Highly Crystalline Nio Nanocubes And Nanorods Fabricated By Evaporation, Dapeng Chen, Xiaolin Wang, Yi Du, Song Ni, Zi-Bin Chen, Xiaozhou Liao
Faculty of Engineering - Papers (Archive)
A new approach to the preparation of regularly shaped NiO nanocubes and nanorods by an infrared heating evaporation method is presented. The growth model is proposed to be a vapor−solid mechanism. The morphology of the nanocrystals can be tuned by the carrier gas flow rate. The samples consist of nanocrystals that are highly crystallized with atomic-scale smooth surfaces. This novel method could be extended to nanocrystal growth of other oxides with low volatility or high melting points. The results of magnetic characterization indicate that the NiO nanorods and nanocubes grown from a mixed target both show weak ferromagnetic states at …
"Oxygen-Vacancy Effect On Structural, Magnetic, And Ferroelectric Properties In Multiferroic Ymno3 Single Crystals", Dapeng Chen, Yi Du, Xiaolin Wang, Zhenxiang Cheng, S. X. Dou, Zhi W. Lin, Jian G. Zhu, Bo Xu
"Oxygen-Vacancy Effect On Structural, Magnetic, And Ferroelectric Properties In Multiferroic Ymno3 Single Crystals", Dapeng Chen, Yi Du, Xiaolin Wang, Zhenxiang Cheng, S. X. Dou, Zhi W. Lin, Jian G. Zhu, Bo Xu
Faculty of Engineering - Papers (Archive)
"We have investigated the structural, magnetic, and ferroelectric properties of magnetically frustrated multiferroic YMnO3 single crystals. The ferroelectric domain structures of YMnO3 samples were studied by piezoresponse force microscopy. Instead of domain vortex structure in stoichiometric crystals, YMnO3-delta exhibits a random domain configuration with straight domain walls. In magnetic measurements, the YMnO3-delta crystal shows typical antiferromagnetic behavior with higher Neel temperature and lower magnetization compared to the stoichiometric sample. The ordered oxygen vacancies dominate multiferroicity through tailoring the domain wall structure. (C) 2012 American Institute of Physics. [doi:10.1063/1.3676000]"
A Significant Improvement In The Superconducting Properties Of Mgb2 By Co-Doping With Graphene And Nano-Sic, K S B De Silva, X Xu, Xiaolin Wang, D Wexler, D Attard, F Xiang, S. X. Dou
A Significant Improvement In The Superconducting Properties Of Mgb2 By Co-Doping With Graphene And Nano-Sic, K S B De Silva, X Xu, Xiaolin Wang, D Wexler, D Attard, F Xiang, S. X. Dou
Faculty of Engineering - Papers (Archive)
The effects of graphene (G) and nanosilicon carbide (SiC) co-doping on the superconducting properties of MgB2 were studied using bulk samples. SiC remains one of the best dopants which can significantly improve the high field performance, while graphene is emerging as a new dopant for MgB2, which can improve the zero field critical current density (Jc). The superconducting properties characterized by Jc, the intergrain connectivity, and the critical fields were significantly improved by the use of both SiC and graphene as dopants.
Crystal Structure, Electronic Structure And Thermoelectric Properties Of N-Type Bisbste2, Sima Aminorroaya-Yamini, Chao Zhang, Xiaolin Wang, Ivan Nevirkovets
Crystal Structure, Electronic Structure And Thermoelectric Properties Of N-Type Bisbste2, Sima Aminorroaya-Yamini, Chao Zhang, Xiaolin Wang, Ivan Nevirkovets
Faculty of Engineering - Papers (Archive)
N-type bismuth telluride sulfide has received attention as a potential thermoelectric material due to its large thermopower and ability to form solid solutions with bismuth antimony sulfide. Here, we fabricated an n-type tetradymite BiSbSTe2 by solid-state reaction. The crystal structure was found to be rhombohedral, and the thermoelectric properties were measured for the temperature range 50–390 K. A high Seebeck coefficient of −190 μVK−1 was achieved at 385 K. The electronic structure of BiSbSTe2 was investigated using first-principles calculations and compared with its parent counterpart (Bi2STe2). The results have shown that BiSbSTe2 is a narrow band-gap semiconductor. For the first …
Structural Properties And Magnetic Phase Transition In Honi2mn (57fe), Jianli Wang, Stewart J. Campbell, M Hofmann, M Hoelzel, Rong Zeng, S. X. Dou, S J. Kennedy
Structural Properties And Magnetic Phase Transition In Honi2mn (57fe), Jianli Wang, Stewart J. Campbell, M Hofmann, M Hoelzel, Rong Zeng, S. X. Dou, S J. Kennedy
Faculty of Engineering - Papers (Archive)
"The structural and magnetic properties of HoNi2Mn (57Fe) have been investigated.The Fe-57-doped HoNi2Mn compound crystallizes in the MgCu2-type structure with Fd-3m space group similar to HoNi2 and HoMn2.HoNi2Mn (57Fe) exhibits ferrimagnetic ordering below a Curie temperature of T-C similar to 60 K-significantly higher than the corresponding values for HoNi2 (T-C - 15 K) and HoMn2 (T-C 24 K)-with analyses of dc magnetization and ac susceptibility results confirming that the magnetic transition at T-C is second order.The Mossbauer spectra above T-C are described well by two sub-spectra representing the 8a and 16d sites while below T-C the spectra have been fitted …
Facile Synthesis Of Graphene-Molybdenum Dioxide And Its Lithium Storage Properties, Kuok Hau Seng, Guo Dong Du, Li Li, Zhixin Chen, Hua-Kun Liu, Zaiping Guo
Facile Synthesis Of Graphene-Molybdenum Dioxide And Its Lithium Storage Properties, Kuok Hau Seng, Guo Dong Du, Li Li, Zhixin Chen, Hua-Kun Liu, Zaiping Guo
Faculty of Engineering - Papers (Archive)
Graphene–molybdenum dioxide composites in several ratios have been prepared through a facile synthesis method. Depending on the ratio, the as synthesized composites have either 2-dimensional graphene sheets with MoO2 particles anchored to them or a clustered agglomerate morphology. The composites have been characterised using Raman spectroscopy, X-ray diffraction, and electron diffraction to confirm the monoclinic MoO2 phase that is present. Lithium storage properties of the as-synthesised samples were tested in a coin-type half cell assembly to determine the relationship between the ratio and the electrochemical performance. The sample with highest amount of MoO2 (78 wt%) displayed the most promising lithium …
Enhanced Electrochemical Properties Of Lifepo4 By Mo-Substitution And Graphitic Carbon-Coating Via A Facile And Fast Microwave-Assisted Solid-State Reaction, Dan Li, Yudai Huang, Neeraj Sharma, Zhixin Chen, Dianzeng Jia, Zaiping Guo
Enhanced Electrochemical Properties Of Lifepo4 By Mo-Substitution And Graphitic Carbon-Coating Via A Facile And Fast Microwave-Assisted Solid-State Reaction, Dan Li, Yudai Huang, Neeraj Sharma, Zhixin Chen, Dianzeng Jia, Zaiping Guo
Faculty of Engineering - Papers (Archive)
A composite cathode material for lithium ion battery applications, Mo-doped LiFePO4/C, is obtained through a facile and fast microwave-assisted synthesis method. Rietveld analysis of LiFePO4-based structural models using synchrotron X-ray diffraction data shows that Mo-ions substitute onto the Fe sites and displace Fe-ions to the Li sites. Supervalent Mo6+ doping can act to introduce Li ion vacancies due to the charge compensation effect and therefore facilitate lithium ion diffusion during charging/discharging. Transmission electron microscope images demonstrate that the pure and doped LiFePO4 nanoparticles were uniformly covered by an approximately 5 nm thin layer of graphitic carbon. Amorphous carbon on the …
Electrical And Thermoelectric Properties Of Single-Wall Carbon Nanotube Doped Bi2te3, Y Zhang, Xiaolin Wang, W K. Yeoh, R K. Zeng, C Zhang
Electrical And Thermoelectric Properties Of Single-Wall Carbon Nanotube Doped Bi2te3, Y Zhang, Xiaolin Wang, W K. Yeoh, R K. Zeng, C Zhang
Faculty of Engineering - Papers (Archive)
The effects of single-wall carbon nanotube (SWCNT) doping in n-type Bi2Te3 bulk samples on the electrical and thermal transport properties have been studied. Bi2Te3 samples doped with 0–5 wt. % SWCNTs were fabricated using solid state reaction and investigated using x-ray diffraction, transmission electron microscopy, and magneto transport measurements. Results show that the 0.5% doping results in the significant enhancement of the Seebeck coefficience to as high as -231.8 lV/K, giant magneto resistance of up to 110%, reduction of thermal conductivity, and change of sign of the Seebeck coefficient from n to p type depending on the doping level and …
Microstructure And Mechanical Properties Of If Steel Deformed During Plane Stress Local Torsion, A H. Shamdani, S Khoddam, P F. Thomson, A Dehghan-Manshadi
Microstructure And Mechanical Properties Of If Steel Deformed During Plane Stress Local Torsion, A H. Shamdani, S Khoddam, P F. Thomson, A Dehghan-Manshadi
Faculty of Engineering - Papers (Archive)
Mechanical joints are inherently vulnerable to failure because the presence of the joint hole causes a stress concentration in the vicinity of the hole. The need for improvement of material strength around a fastener hole can be satisfied by severe plastic deformation (SPD) to produce ultrafine grains. The ultrafine grained (UFG) alloys produced by SPD processing possess higher strengths than their coarse-grained counterparts as a result of the reduced grain size. However, in some circumstances such as SPD processing of Al-Zn and Al-Mg alloys the decomposition of supersaturated solid solutions competes with the Hall-Petch effect and leads to a more …
Dependence Of Magnetoelectric Properties On Sintering Temperature For Nano-Sic-Doped Mgb2/Fe Wires Made By Combined In Situ/Ex Situ Process, Wenxian Li, Rong Zeng, Jiazhao Wang, Y Li, S. X. Dou
Dependence Of Magnetoelectric Properties On Sintering Temperature For Nano-Sic-Doped Mgb2/Fe Wires Made By Combined In Situ/Ex Situ Process, Wenxian Li, Rong Zeng, Jiazhao Wang, Y Li, S. X. Dou
Faculty of Engineering - Papers (Archive)
Very fine nano-SiC particles (nm) were doped into a MgB2 superconductor. The influence of self-field supercurrent on the high-field performance of the nano-SiC-doped MgB2/Fe wires is discussed based on comparison of the critical current densities of the in situ processed nano-SiCdoped MgB2 wires and those of the nano-SiC-doped MgB2/Fe wires processed by the combination of in situ/ex situ methods.
Rapid Microwave-Assisted Synthesis Of Mn3o4-Graphene Nanocomposite And Its Lithium Storage Properties, Li Li, Zaiping Guo, Aijun Du, Hua-Kun Liu
Rapid Microwave-Assisted Synthesis Of Mn3o4-Graphene Nanocomposite And Its Lithium Storage Properties, Li Li, Zaiping Guo, Aijun Du, Hua-Kun Liu
Faculty of Engineering - Papers (Archive)
A nanocomposite of Mn3O4 wrapped in graphene sheets (GSs) was successfully synthesized via a facile, effective, energy-saving, and scalable microwave hydrothermal technique. The morphology and microstructures of the fabricated GS–Mn3O4 nanocomposite were characterized using various techniques. The results indicate that the particle size of the Mn3O4 particles in the nanocomposite markedly decreased to nearly 20 nm, significantly smaller than that for the bare Mn3O4. Electrochemical measurements demonstrated a high specific capacity of more than 900 mA h g−1 at 40 mA g−1, and excellent cycling stability with no capacity decay can be observed up to 50 cycles. All of these …
Effect Of Ti And N Concentrations On Microstructure And Mechanical Properties Of Microalloyed High Strength Line Pipe Steel Welds, Leigh Fletcher, Zhixiong Zhu, Marimuthu Murugananth, Lei Zheng, Mingzhuo Bai, Huijun Li, F Barbaro
Effect Of Ti And N Concentrations On Microstructure And Mechanical Properties Of Microalloyed High Strength Line Pipe Steel Welds, Leigh Fletcher, Zhixiong Zhu, Marimuthu Murugananth, Lei Zheng, Mingzhuo Bai, Huijun Li, F Barbaro
Faculty of Engineering - Papers (Archive)
A selection of nine heats of line pipe steel from the same project with different Ti and N content were used to evaluate the effects of Ti/N ratio on weld zone microstructure, hardness and prior austenite grain size (PAGS) in the coarse grained heat-affected zone (CGHAZ). It was shown that the microstructure of the base metal (BM) mainly consisted of fine grained polygonal ferrite with fine islands of pearlite. The weld metal (WM) microstructure was predominantly acicular ferrite with a small volume fraction of pro-eutectoid ferrite. The CGHAZ consisted of bainitic ferrite and islands of martensite-austenite. The inside region of …
Magnetic Properties In Polycrystalline And Single Crystal Ca-Doped Lacoo3, R Zeng, J C. Debnath, Dapeng Chen, P Shamba, Jianli Wang, S J. Kennedy, S J. Campbell, Tania M. Silver, S. X. Dou
Magnetic Properties In Polycrystalline And Single Crystal Ca-Doped Lacoo3, R Zeng, J C. Debnath, Dapeng Chen, P Shamba, Jianli Wang, S J. Kennedy, S J. Campbell, Tania M. Silver, S. X. Dou
Faculty of Engineering - Papers (Archive)
Polycrystalline (PC) and single crystalline (SC) Ca-doped LaCoO3 (LCCO) samples with the perovskite structure were synthesized by conventional solid-state reaction and the floating-zone growth method. We present the results of a comprehensive investigation of the magnetic properties of the LCCO system. Systematic measurements have been conducted on dc magnetization, ac susceptibility, exchange-bias, and the magnetocaloric effect. These findings suggest that complex structural phases, ferromagnetic (FM), and spin-glass/cluster-spin-glass (CSG), and their transitions exist in PC samples, while there is a much simpler magnetic phase in SC samples. It was also of interest to discover that the CSG induced a magnetic …
Structural, Dielectric, Antiferromagnetic, And Thermal Properties Of The Frustrated Hexagonal Ho1-Xerxmno3 Manganites, Peng Liu, Xiaolin Wang, Zhenxiang Cheng, Yi Du, Hideo Kimura
Structural, Dielectric, Antiferromagnetic, And Thermal Properties Of The Frustrated Hexagonal Ho1-Xerxmno3 Manganites, Peng Liu, Xiaolin Wang, Zhenxiang Cheng, Yi Du, Hideo Kimura
Faculty of Engineering - Papers (Archive)
The Er doping effects on the structural, dielectric, ferroelectric, magnetic, and thermal properties of the hexagonal Ho1-xErxMnO3 (0 ≤ x ≤ 1) compounds synthesized by the solid-state reaction method have been investigated by Rietveld refinement and by measurements of dielectric constant, ferroelectric hysteresis loops, magnetic susceptibility, and specific heat. The a lattice parameter decreases as the Er content increases, whereas the c lattice parameter nearly keeps constant with pretty minor fluctuations. Dielectric data and ferroelectric hysteresis loops show all the samples are not only ferroelectric materials with leaky nature, but also with dielectric relaxation related …
Fabrication, Magnetic, And Ferroelectric Properties Of Multiferroic Bifeo3 Hollow Nanoparticles, Yi Du, Zhenxiang Cheng, S X. Dou, Darren J. Attard, Xiaolin Wang
Fabrication, Magnetic, And Ferroelectric Properties Of Multiferroic Bifeo3 Hollow Nanoparticles, Yi Du, Zhenxiang Cheng, S X. Dou, Darren J. Attard, Xiaolin Wang
Faculty of Engineering - Papers (Archive)
Hollow BiFeO3 nanoparticles were synthesized by an electrospray route for the first time. The phase purity and structure have been investigated by x-ray diffraction and Raman spectroscopy. Transmission and scanning electron microscope investigations revealed that the as-obtained BiFeO3 hollow spheres were polycrystalline, with a shell thickness of 35 nm. The formation mechanism can be possibly explained by Ostwald ripening. Raman spectra have verified decreased vibrational frequencies in BiFeO3 nanoparticles. These hollow and core-shell multiferroic nanoparticles exhibit significantly enhanced ferromagnetism from 5 to 600 K due to a broken spiral spin structure. The ferroelectricity of hollow BiFeO3 …
Magnetic And Ferroelectric Properties Of Multiferroic Bi2nimno6 Nanoparticles, Yi Du, Zhenxiang Cheng, Xiaolin Wang, Peng Liu, S. X. Dou
Magnetic And Ferroelectric Properties Of Multiferroic Bi2nimno6 Nanoparticles, Yi Du, Zhenxiang Cheng, Xiaolin Wang, Peng Liu, S. X. Dou
Faculty of Engineering - Papers (Archive)
Multiferroic Bi2NiMnO6 nanoparticles were synthesized by a simple electrospray method. Bi2NiMnO6 nanoparticles crystallize in the monoclinic structure with space group C121. The particles show a uniform spherical shape with a diameter of 100 nm to 300 nm. The ferromagnetic transition of Bi2NiMnO6 is confirmed at 122 K. The room temperature ferroelectricity of the Bi2NiMnO6 nanoparticles is verified by Kelvin probe force microscopy.
Microstructure And Mechanical Properties After Annealing Of Equal-Channel Angular Pressed Interstitial-Free Steel, Sujoy S. Hazra, Elena V. Pereloma, Azdiar A. Gazder
Microstructure And Mechanical Properties After Annealing Of Equal-Channel Angular Pressed Interstitial-Free Steel, Sujoy S. Hazra, Elena V. Pereloma, Azdiar A. Gazder
Faculty of Engineering - Papers (Archive)
The evolution of microstructure, microtexture and mechanical properties during isothermal annealing of an ultrafine-grained interstitial-free steel after eight passes of route BC room temperature equal-channel angular pressing (ECAP) was studied. The microstructure and microtexture were characterized by electron back-scattering diffraction, and mechanical properties were assessed by shear punch and uniaxial tensile testing. Homogeneous coarsening via continuous recrystallization of the ECAP microstructure is accompanied by minor changes in the ∼63% high-angle boundary population and a sharpening of the original ECAP texture. This is followed by abnormal growth during the final stages of softening due to local growth advantages. Linear correlations …
Effect Of Different Additives On The Hydrogen Storage Properties Of The Mgh 2-Lialh 4 Destabilized System, S X. Dou, Yue Zhao, Xuebin Yu, Mohammad Ismail
Effect Of Different Additives On The Hydrogen Storage Properties Of The Mgh 2-Lialh 4 Destabilized System, S X. Dou, Yue Zhao, Xuebin Yu, Mohammad Ismail
Faculty of Engineering - Papers (Archive)
The hydrogen storage properties of the MgH2-LiAlH4 (4 : 1) composite system with and withoutadditives were studied. 5 wt.% of TiF3, NbF5, NiF2, CrF2, YF3, TiCl3?1/3AlCl3, HfCl4, LaCl3, CeCl3,and NdCl3, respectively, was added to the MgH2-LiAlH4 (4 : 1) mixture, and their catalytic effect wasinvestigated. Temperature programmed desorption results show that addition of metal halides to theMgH2-LiAlH4 (4 : 1) composite system improves the onset desorption temperature. The hydrogendesorption properties of metal halide-doped MgH2-LiAlH4 (4 : 1) composites were also improved ascompared to the undoped MgH2-LiAlH4 (4 : 1) composite. Furthermore, the activation energy andthe change in enthalpy in the …
The Effects Of Size And Orientation On Magnetic Properties And Exchange Bias In Co3o4 Mesoporous Nanowires, Rong Zeng, J Q Wang, Zhixin Chen, Wenxian Li, S. X. Dou
The Effects Of Size And Orientation On Magnetic Properties And Exchange Bias In Co3o4 Mesoporous Nanowires, Rong Zeng, J Q Wang, Zhixin Chen, Wenxian Li, S. X. Dou
Faculty of Engineering - Papers (Archive)
Co3O4 mesoporous nanowires with average single crystalline grain sizes of about 8 nm, 12nm, 25 nm, and 45 nm were synthesized by sintering of microwave-assisted hydrothermal processed belt-Co(OH)2 precursors at 300–500 °C for 2 h. Microstructure analysis was conducted by x-ray diffraction, x-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), field emission SEM (FESEM), transmission electron microscopy (TEM), and high resolution TEM (HRTEM) to confirm the composition, structure, and orientation in the nanowires. Systematic magnetic measurements have also been conducted on the nanowires. It was found that the size and orientation have significant effects on …
Removal Of Trace Organics By Mbr Treatment: The Role Of Molecular Properties, Nichanan Tadkaew, Faisal I. Hai, James A. Mcdonald, Stuart J. Khan, Long Nghiem
Removal Of Trace Organics By Mbr Treatment: The Role Of Molecular Properties, Nichanan Tadkaew, Faisal I. Hai, James A. Mcdonald, Stuart J. Khan, Long Nghiem
Faculty of Engineering - Papers (Archive)
This study examined the relationship between specific molecular features of trace organic contaminants and their removal efficiencies by a laboratory scale membrane bioreactor (MBR). Removal efficiencies of 40 trace organic compounds were assessed under stable operating conditions. The reported results demonstrate an apparent correlation between chemical structures and the removal of trace organic contaminants by the laboratory scale MBR system. The removal of all 14 very hydrophobic (Log D > 3.2) trace organic compounds selected in this study was consistently high and was above 85%. The occurrence and types of electron withdrawing or donating functional groups appear to be important factors …
Superconducting Properties Of Graphene Doped Magnesium Diboride, Xun Xu, Wenxian Li, Xiaolin Wang, S. X. Dou
Superconducting Properties Of Graphene Doped Magnesium Diboride, Xun Xu, Wenxian Li, Xiaolin Wang, S. X. Dou
Faculty of Engineering - Papers (Archive)
Graphene, carbon in the form of monolayer sheets, has revealed astonishing and unique chemical and physical properties, which have made it an extremely active research topic in both materials science and physics (Novoselov, K. S. et al., 2004). Through chemical and materials integration, graphene is being actively exploited in a range of technological applications (Stankovich, S. et al., 2006). Superconductors can carry electrical current without any energy dissipation. The combination of both graphene and a superconductor into a composite has great potential for electrical devices and large scale applications. MgB2, a superconductor with a simple composition and two-gap feature has …
Effects Of Cu And Fe Doping On Raman Spectra And On The Structural And Magnetic Properties Of Ermno3, Peng Liu, Zhenxiang Cheng, Yi Du, Xiaolin Wang
Effects Of Cu And Fe Doping On Raman Spectra And On The Structural And Magnetic Properties Of Ermno3, Peng Liu, Zhenxiang Cheng, Yi Du, Xiaolin Wang
Faculty of Engineering - Papers (Archive)
Single phase ErMexMn1−xO3 (Me = Cu, Fe; 0 ≤ x ≤ 0.1) samples were synthesized by the solid state reaction method. The differences between the doping effects on the Raman spectra and on the structural, magnetic, and thermal properties of the two systems have been systematically investigated. In the ErCuxMn1−xO3 system, lattice parameter a increases with doping, while lattice parameter c decreases. It is more complicated in the ErFexMn1−xO3 system, where lattice parameter a decreases with doping, while lattice parameter c is enhanced after an …
Structural And Superconducting Properties Of Lafeas1-Xsbxo1-Yfy, Cao Wang, Zhifeng Ma, Shuai Jiang, Yuke Li, Zhu-An Xu, Guanghan Cao
Structural And Superconducting Properties Of Lafeas1-Xsbxo1-Yfy, Cao Wang, Zhifeng Ma, Shuai Jiang, Yuke Li, Zhu-An Xu, Guanghan Cao
Faculty of Engineering - Papers (Archive)
We report the antimony (Sb) doping effect in a prototype system of iron-based superconductors LaFeAsO1−y F y (y=0, 0.1, 0.15). X-ray powder diffraction indicates that the lattice parameters increase with Sb content within the doping limit. Rietveld structural refinements show that, with the partial substitution of Sb for As, the thickness of the Fe2As2 layers increases significantly, whereas that of the La2O2 layers shrinks simultaneously. So a negative chemical pressure is indeed “applied” to the superconducting-active Fe2As2 layers, in contrast to the effect of positive chemical pressure …
Effect Of Microstructural Morphology On The Mechanical Properties Of Titanium Alloys, A Dehghan-Manshadi, Mark H. Reid, R J. Dippenaar
Effect Of Microstructural Morphology On The Mechanical Properties Of Titanium Alloys, A Dehghan-Manshadi, Mark H. Reid, R J. Dippenaar
Faculty of Engineering - Papers (Archive)
Different morphologies of α+β microstructures were obtained in a commercial Ti-6Al-4V alloy by cooling at different rates from the single β-phase region into the two phase region. The effect of such morphologies on mechanical properties was studied using hot compression tests in a Gleeble thermomechanical simulator. A variety of complex morphologies could be obtained since the cooling rate has a significant influence on the β to α phase transformation and the resulting morphological development. While most of the β phase transformed to colonies of α at high cooling rates, it was possible to obtain a complex mixture of a colonies, …
Mechanical, Microstructure And Texture Properties Of Interstitial-Free Steel And Copper Subjected To Equal Channel Angular Extrusion And Cold-Rolling, A A. Gazder, S S. Hazra, C F. Gu, W Q. Cao, C H J Davies, E V. Pereloma
Mechanical, Microstructure And Texture Properties Of Interstitial-Free Steel And Copper Subjected To Equal Channel Angular Extrusion And Cold-Rolling, A A. Gazder, S S. Hazra, C F. Gu, W Q. Cao, C H J Davies, E V. Pereloma
Faculty of Engineering - Papers (Archive)
Interstitial-free steel and OFHC copper were subjected to 8 passes, route BC room temperature ECAE followed by cold-rolling up to 97.5% thickness reduction. Uniaxial tensile tests and Electron Back-Scattering Diffraction were used to characterise the evolution in mechanical properties, microstructure refinement and micro-texture. IF-steel showed continuous increase in strength whereas Cu returned reduced strength and a small gain in ductility at 97.5% reduction. In both metals substructure refinement was accompanied by an increase in high-angle boundary fraction, average misorientation and a slight increase in Σ3 boundaries. An evolution of crystallographic orientations from negative shear to predominantly cold-rolled textures after …
High-Surface-Area -Fe2o3/Carbon Nanocomposite: One-Step Synthesis And Its Highly Reversible And Enhanced High-Rate Lithium Storage Properties, S X. Dou, David Wexler, Jiazhao Wang, Hua-Kun Liu, Konstantin K. Konstantinov, Chao Zhong, Shulei Chou
High-Surface-Area -Fe2o3/Carbon Nanocomposite: One-Step Synthesis And Its Highly Reversible And Enhanced High-Rate Lithium Storage Properties, S X. Dou, David Wexler, Jiazhao Wang, Hua-Kun Liu, Konstantin K. Konstantinov, Chao Zhong, Shulei Chou
Faculty of Engineering - Papers (Archive)
Hollow-structured α-Fe2O3/carbon (HIOC) nanocomposite with a high surface area of around 260 m2 g−1 was synthesized by a one-step, in situ, and industrially-oriented spray pyrolysis method using iron lactate and sucrose solution as the precursors. The small α-Fe2O3 nanocrystals were highly dispersed inside amorphous carbon to form a carbon nanocomposite. Electrochemical measurements showed that the carbon played an important role in affecting both the cycle life and the rate capability of the electrode. The HIOC composites showed the best electrochemical performance in terms of high capacity (1210 mAh g−1 …
Controllable Reflection Properties Of Nanocomposite Photonic Crystals Constructed By Semiconductor Nanocrystallites And Natural Periodic Bio-Matrices, Jie Han, Huilan Su, Fang Song, Di Zhang, Zhixin Chen
Controllable Reflection Properties Of Nanocomposite Photonic Crystals Constructed By Semiconductor Nanocrystallites And Natural Periodic Bio-Matrices, Jie Han, Huilan Su, Fang Song, Di Zhang, Zhixin Chen
Faculty of Engineering - Papers (Archive)
In this contribution, the subtle periodic nanostructures in butterfly wings and peacock feathers are applied as natural PhC matrices to in situ embed CdS nanocrystallites (nano-CdS) on the structure surface via a convenient solution process. The resulting nano-CdS/natural PhCs nanocomposites show typical 1D, quasi 1D and 2D PhC structures at the nanoscale, which is inherited from the corresponding natural periodic bio-matrices. Moreover, their reflection properties are investigated and show dependence on PhC type, structure parameter, loading amount, as well as collecting angle. This work suggests that natural periodic bio-structures could be perfect matrices to construct novel nanocomposite PhCs, whose photonic …