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Full-Text Articles in Engineering
Multifunctionality From Coexistence Of Large Magnetoresistance And Magnetocaloric Effect In La0.7ca0.3mno3, J. C. Debnath, R. Zeng, J. H. Kim, S. X. Dou
Multifunctionality From Coexistence Of Large Magnetoresistance And Magnetocaloric Effect In La0.7ca0.3mno3, J. C. Debnath, R. Zeng, J. H. Kim, S. X. Dou
Faculty of Engineering - Papers (Archive)
We report the existence of multifunctionality involving large magnetoresistance (MR) and magnetocaloric effect (MCE) near room temperature in La0.7Ca0.3MnO3. A peak in the temperature dependence of the magnetoresistance and a change in the magnetic entropy (ΔSM) are observed at 251 K, with a maximum magnetoresistance MR (defined as ρ(0)∕ρ(H)−1) of about 206% and a maximum ΔSM of approximately 7.54 J∕kgK, at a field of 5 T, where the Curie temperature (TC) and metal‐insulator transition coexist at 251 K. The magnetic entropy change is measured on the basis of resistive …
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 …
Effect Of The Carbon Nanotube Surface Characteristics On The Conductivity And Dielectric Constant Of Carbon Nanotube/Poly(Vinylidene Fluoride) Composites, S A. Carabineiro, Manuel F. Pereira, J Nunes-Pereira, Cristina Caparrós, Vitor Sencadas, Senentxu Lanceros-Méndez
Effect Of The Carbon Nanotube Surface Characteristics On The Conductivity And Dielectric Constant Of Carbon Nanotube/Poly(Vinylidene Fluoride) Composites, S A. Carabineiro, Manuel F. Pereira, J Nunes-Pereira, Cristina Caparrós, Vitor Sencadas, Senentxu Lanceros-Méndez
Faculty of Engineering and Information Sciences - Papers: Part A
Commercial multi-walled carbon nanotubes (CNT) were functionalized by oxidation with HNO3, to introduce oxygen-containing surface groups, and by thermal treatments at different temperatures for their selective removal. The obtained samples were characterized by adsorption of N2 at -196°C, temperature-programmed desorption and determination of pH at the point of zero charge. CNT/poly(vinylidene fluoride) composites were prepared using the above CNT samples, with different filler fractions up to 1 wt%. It was found that oxidation reduced composite conductivity for a given concentration, shifted the percolation threshold to higher concentrations, and had no significant effect in the dielectric response.
Effect Of Magnetostatic Field On Microstructure Of 5005 Aluminum Alloy Sheet By Roll-Casting, Jintao Li, Guangming Xu, Jianzhong Cui
Effect Of Magnetostatic Field On Microstructure Of 5005 Aluminum Alloy Sheet By Roll-Casting, Jintao Li, Guangming Xu, Jianzhong Cui
Faculty of Engineering and Information Sciences - Papers: Part A
The roll-casting technology of 5000 series aluminum alloy is one of the difficulties at present. Roll-casting technology was employed in this paper and high quality 5005 aluminum alloy sheets were fabricated successfully under different conditions. The solidification of melt in roll-casting process is the rapid directional solidification. The effect of magnetostatic field on microstructure of 5005 aluminum alloy sheet by roll-casting has been investigated and analyzed. The results indicate that imposing magnetostatic field can refine the grains of 5005 aluminum alloy.
The Effect Of Sulfur Concentration In Liquid Iron On Mineral Layer Formation During Coke Dissolution, Michael W. Chapman, Brian J. Monaghan, Sharon Nightingale, John G. Mathieson, Robert J. Nightingale
The Effect Of Sulfur Concentration In Liquid Iron On Mineral Layer Formation During Coke Dissolution, Michael W. Chapman, Brian J. Monaghan, Sharon Nightingale, John G. Mathieson, Robert J. Nightingale
Faculty of Engineering - Papers (Archive)
The effects of sulfur concentration in liquid iron on mineral layer development between coke and iron as coke dissolves in a 2 mass % carbon-iron liquid have been investigated at 1500°C. Initial sulfur in iron concentrations used ranged from 0.006 to 0.049 mass %. Key findings include that the two stage dissolution behavior exhibited in the carbon transfer from coke to iron as reported in a previous study by the authors, at low initial sulfur in iron contents, was also apparent at the higher values used in this study. This two stage behavior was attributed to a change in the …
Effect Of Fouling On Removal Of Trace Organic Compounds By Nanofiltration, Shima Hajibabania, A Verliefde, Jörg E Drewes, Long Nghiem, J Mc Donald, S Khan, P Le-Clech
Effect Of Fouling On Removal Of Trace Organic Compounds By Nanofiltration, Shima Hajibabania, A Verliefde, Jörg E Drewes, Long Nghiem, J Mc Donald, S Khan, P Le-Clech
Faculty of Engineering - Papers (Archive)
The fate of chemical of concern is not yet fully understood during treatment of impaired waters. The aim of this paper is to assess the impact of different organic-based fouling layers on the removal of a large range of trace organics. Both model and real water samples (mixed with trace organic contaminants at environmental concentration of 2 μg l−1) were used to simulate fouling in nanofiltration under controlled environment. The new and fouled membranes were systematically characterised for surface charge, hydrophobicity and roughness. It was observed that fouling generally reduced the membrane surface charge; however, the alterations of the membrane …
Effect Of Initial Static Shear Stress On The Undrained Cyclic Behavior Of Saturated Sand By Torsional Shear Loading, Gabriele Chiaro, Takeshi Sato, Takashi Kiyota, Junichi Koseki
Effect Of Initial Static Shear Stress On The Undrained Cyclic Behavior Of Saturated Sand By Torsional Shear Loading, Gabriele Chiaro, Takeshi Sato, Takashi Kiyota, Junichi Koseki
Faculty of Engineering - Papers (Archive)
With the aim of gaining a better understanding of the role which the static shear plays on the large-deformation behavior of saturated sand, a series of undrained cyclic torsional shear tests on saturated Toyoura sand specimens up to single amplitude shear strain of about 50 % were performed. Several hollow cylinder specimens at relative density of 44 - 48 % were tested while varying the initial static shear and the subsequent cyclic shear stress levels. Depending on the degree of stress reversal, the loading pattern could be classified into three groups: stress reversal, intermediate and non-reversal. The observed failure behavior …
Mr Damper In Reducing Pounding Effect Of Base-Isolated Rc Highway Bridge, M Neaz Sheikh, Jingya Xiong, Weihua Li
Mr Damper In Reducing Pounding Effect Of Base-Isolated Rc Highway Bridge, M Neaz Sheikh, Jingya Xiong, Weihua Li
Faculty of Engineering - Papers (Archive)
Significant structural damage due to pounding between adjacent superstructures of multispan reinforced concrete (RC) highway bridges has been observed in past earthquakes. Different methods have been proposed in the literature to mitigate the adverse pounding effect. This paper presents an analytical investigation on the use of magnetorheological (MR) dampers in reducing the pounding effect of base-isolated multi-span RC highway bridges. It has been observed that MR damper can effectively reduce adverse pounding effect. Three control strategies (passive off, passive on, and bang bang control) of MR damper have been investigated. Although all the control strategies are found to be effective, …
Effect Of Thermal Strain On J(C) And T-C In High Density Nano-Sic Doped Mgb2, Wenxian Li, Rong Zeng, Lin Lu, S. X. Dou
Effect Of Thermal Strain On J(C) And T-C In High Density Nano-Sic Doped Mgb2, Wenxian Li, Rong Zeng, Lin Lu, S. X. Dou
Faculty of Engineering - Papers (Archive)
The influences of lattice strain on the superconducting critical current density Jc and critical transition temperature Tc in pure MgB2 and a SiC-MgB2 composite made by the diffusion process are explored, based on the thermal expansion coefficients and the low temperature effects on Raman scattering. The strong thermal strain provides a strong flux pinning force for the supercurrents at the interfaces between SiC and MgB2. The high Tc of SiC-MgB2 is also discussed according to the expanded lattice and Raman characteristics.
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 …
Bauschinger Effect In Microalloyed Steels: Part Ii. Influence Of Work Softening On Strength Development During Uoe Line-Pipe Forming, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis
Bauschinger Effect In Microalloyed Steels: Part Ii. Influence Of Work Softening On Strength Development During Uoe Line-Pipe Forming, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis
Faculty of Engineering and Information Sciences - Papers: Part A
The Bauschinger effect (a reduced yield stress at the start of reverse deformation following forward prestrain) is an important factor of strength development for cold metal forming technology. In steels, the magnitude of the Bauschinger effect depends on composition, through the presence of microalloy precipitates, and prior processing, through the size and distribution of the microalloy precipitates and the presence of retained work hardening. In this article, the parameters of the Bauschinger effect and work hardening (coefficient and exponent) in forward and reverse deformations were quantitatively related to the particle number density and dislocation density for two high-strength low-alloy (HSLA) …
Magnetocaloric Effect In Layered Ndmn2ge0.4si1.6, Jianli Wang, S.J Campbell, J.M Cadogan, A J Studer, Rong Zeng, S. X. Dou
Magnetocaloric Effect In Layered Ndmn2ge0.4si1.6, Jianli Wang, S.J Campbell, J.M Cadogan, A J Studer, Rong Zeng, S. X. Dou
Faculty of Engineering - Papers (Archive)
A giant magnetocaloric effect has been observed in NdMn2Ge0.4Si1.6 associated with the first-order magnetic phase transition from antiferromagnetism to ferromagnetism around TC = 36 K. The magnetic entropy change –ΔSM and adiabatic temperature change ΔTad have been determined from magnetization and specific heat measurements (B = 0–5 T) with –ΔSM calculated by the Maxwell relation and Clausius–Clapeyron method. The values –ΔSMmax = 12.3 J kg−1 K−1 and refrigerant capacity ∼ 95 J/kg for ΔB = 0–2 T as derived from …