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The Magnetocaloric Effect And Critical Behaviour Of The Mn0.94ti0.06coge Alloy, P Shamba, Jianli Wang, J C. Debnath, S J. Kennedy, Rong Zeng, M F Md Din, F Hong, Z X. Cheng, A J. Studer, S X. Dou Jul 2013

The Magnetocaloric Effect And Critical Behaviour Of The Mn0.94ti0.06coge Alloy, P Shamba, Jianli Wang, J C. Debnath, S J. Kennedy, Rong Zeng, M F Md Din, F Hong, Z X. Cheng, A J. Studer, S X. Dou

Jianli Wang

Structural, magnetic and magnetocaloric properties of the Mn0.94Ti0.06CoGe alloy have been investigated using x-ray diffraction, DC magnetization and neutron diffraction measurements. Two phase transitions have been detected, at T-str = 235 K and T-C = 270 K. A giant magnetocaloric effect has been obtained at around Tstr associated with a structural phase transition from the low temperature orthorhombic TiNiSi-type structure to the high temperature hexagonal Ni2In-type structure, which is confirmed by neutron study. In the vicinity of the structural transition, at T-str, the magnetic entropy change, -Delta S-M reached a maximum value of 14.8 J kg(-1) K-1 under a magnetic …


The Effect Of Slag Basicity On Spinal Inclusion Wettability, Hamed Abdeyazdan, Brian J. Monaghan, Neslihan Dogan, M Akbar Rhamdhani Jun 2013

The Effect Of Slag Basicity On Spinal Inclusion Wettability, Hamed Abdeyazdan, Brian J. Monaghan, Neslihan Dogan, M Akbar Rhamdhani

Brian Monaghan

Steel cleanness is an important and growing research area driven by the demands to produce high quality steel. Inclusion content in steel is an important criterion to assess clean steel. MgO.Ah03 spinel inclusions cause problems in steel processing and are generally deleterious to steel products due to their high melting point and high hardness. Jnclusions are generally r· moved by rea ting with slag. This is primarily achieved by optimizing lhe PI' 'ess omliLions to promote contact and reaction between the inclusion and S,l,lg '. or efticient rem val from the steel the inclusions must attach to and dissolve in …


The Effect Of Different Rotation Patterns On The Revisions Of Trend Estimates, David G. Steel, Craig H. Mclaren Jun 2013

The Effect Of Different Rotation Patterns On The Revisions Of Trend Estimates, David G. Steel, Craig H. Mclaren

Professor David Steel

The X11 and X11ARIMA procedures are widely used to produce seasonally adjusted and trend estimates from time series obtained from sample surveys. The surveys are often based on designs in which there is sample overlap between different periods. The degree of overlap is determined by the pattern of inclusion of selected units over time, i.e., the rotation pattern. An important issue in analysing the series is that trend estimates at the end of the series are revised as estimates for recent periods are added. This article considers the effects of different rotation patterns on the mean squared error of the …


The Magnetocaloric Effect And Critical Behaviour Of The Mn0.94ti0.06coge Alloy, P Shamba, Jianli Wang, J C. Debnath, S J. Kennedy, Rong Zeng, M F Md Din, F Hong, Z X. Cheng, A J. Studer, S X. Dou Jun 2013

The Magnetocaloric Effect And Critical Behaviour Of The Mn0.94ti0.06coge Alloy, P Shamba, Jianli Wang, J C. Debnath, S J. Kennedy, Rong Zeng, M F Md Din, F Hong, Z X. Cheng, A J. Studer, S X. Dou

Shi Xue Dou

Structural, magnetic and magnetocaloric properties of the Mn0.94Ti0.06CoGe alloy have been investigated using x-ray diffraction, DC magnetization and neutron diffraction measurements. Two phase transitions have been detected, at T-str = 235 K and T-C = 270 K. A giant magnetocaloric effect has been obtained at around Tstr associated with a structural phase transition from the low temperature orthorhombic TiNiSi-type structure to the high temperature hexagonal Ni2In-type structure, which is confirmed by neutron study. In the vicinity of the structural transition, at T-str, the magnetic entropy change, -Delta S-M reached a maximum value of 14.8 J kg(-1) K-1 under a magnetic …


Effect Of Gallium Doping And Ball Milling Process On The Thermoelectric Performance Of N-Type Zno, Priyanka Jood, Germanas Peleckis, Xiaolin Wang, S X. Dou Jun 2013

Effect Of Gallium Doping And Ball Milling Process On The Thermoelectric Performance Of N-Type Zno, Priyanka Jood, Germanas Peleckis, Xiaolin Wang, S X. Dou

Shi Xue Dou

We report a systematic investigation of the thermoelectric properties of n-type Ga-doped ZnO synthesized using different ball milling conditions. Samples fabricated by the high-energy ball milling resulted in a highly dense layered structure with randomly distributed voids. These samples measured the lowest room temperature thermal conductivity, i.e., 27 W/mK due to increased phonon scattering. Furthermore, the Ga:ZnO system showed a metal–semiconductor transition above 300 K with transition temperature decreasing with increasing doping level. Measurement of the activation energy revealed the presence of one donor level around 3.9–7.8 meV and a deeper donor level around 15.4–18.1 meV below the conduction band …


The Effect Of Different Binders On Electrochemical Properties Of Lini1/3mn1/3c1/3o2 Cathode Material In Lithium Ion Batteries, Jiantie Xu, Shulei Chou, Qinfen Gu, Hua Liu, S Dou Feb 2013

The Effect Of Different Binders On Electrochemical Properties Of Lini1/3mn1/3c1/3o2 Cathode Material In Lithium Ion Batteries, Jiantie Xu, Shulei Chou, Qinfen Gu, Hua Liu, S Dou

Shulei Chou

LiNi1/3Mn1/3Co1/3O2 (NMC) as a cathode material for lithium ion batteries has been synthesized by the sol-gel method. The X-ray diffraction Rietveld refinement results indicated that single-phase NMC with hexagonal layered structure was obtained. Scanning electron microscope images revealed well crystallized NMC with uniform particle size in the range of 100-200 nm. The performance of the NMC electrodes with sodium carboxylmethyl cellulose (CMC), poly(vinylidene fluoride) (PVDF), and alginate from brown algae as binders was compared. Constant current charge-discharge test results demonstrated that the NMC electrode using CMC as binder had the highest rate capability, followed by those using alginate and PVDF …


The Magnetocaloric Effect And Critical Behaviour Of The Mn0.94ti0.06coge Alloy, P Shamba, Jianli Wang, J C. Debnath, S J. Kennedy, Rong Zeng, M F Md Din, F Hong, Z X. Cheng, A J. Studer, S X. Dou Jan 2013

The Magnetocaloric Effect And Critical Behaviour Of The Mn0.94ti0.06coge Alloy, P Shamba, Jianli Wang, J C. Debnath, S J. Kennedy, Rong Zeng, M F Md Din, F Hong, Z X. Cheng, A J. Studer, S X. Dou

Faculty of Engineering and Information Sciences - Papers: Part A

Structural, magnetic and magnetocaloric properties of the Mn0.94Ti0.06CoGe alloy have been investigated using x-ray diffraction, DC magnetization and neutron diffraction measurements. Two phase transitions have been detected, at T-str = 235 K and T-C = 270 K. A giant magnetocaloric effect has been obtained at around Tstr associated with a structural phase transition from the low temperature orthorhombic TiNiSi-type structure to the high temperature hexagonal Ni2In-type structure, which is confirmed by neutron study. In the vicinity of the structural transition, at T-str, the magnetic entropy change, -Delta S-M reached a maximum value of 14.8 J kg(-1) K-1 under a magnetic …


Effect Of Microstructure And Composition On Hydrogen Permeation In X70 Pipeline Steels, Ayesha J. Haq, K Muzaka, D P. Dunne, A Calka, E V. Pereloma Jan 2013

Effect Of Microstructure And Composition On Hydrogen Permeation In X70 Pipeline Steels, Ayesha J. Haq, K Muzaka, D P. Dunne, A Calka, E V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

The influence of microstructure and composition on permeation of hydrogen in 1.2 and 0.5 wt.% Mn X70 pipeline steels after different processing was investigated using an electrochemical permeation technique. For 1.2 wt.% Mn (standard Mn) steel, the microstructure of normalised transfer bar was coarse equiaxed ferrite grains. This sample exhibited the highest diffusivity, followed by transfer bar, with a mixed ferriteebainitic ferrite microstructure; and hot rolled strip, with fine elongated ferrite grains. The 0.5 wt.% Mn (medium Mn) strip displayed lower diffusivity than the 1.2 wt.% Mn strip, due to hydrogen trapping by finer ferrite grains and a higher density …


A Random Effect Block Bootstrap For Clustered Data, Raymond L. Chambers, Hukum Chandra Jan 2013

A Random Effect Block Bootstrap For Clustered Data, Raymond L. Chambers, Hukum Chandra

Faculty of Engineering and Information Sciences - Papers: Part A

Random effects models for hierarchically dependent data, e.g. clustered data, are widely used. A popular bootstrap method for such data is the parametric bootstrap based on the same random effects model as that used in inference. However, it is hard to justify this type of bootstrap when this model is known to be an approximation. In this paper we describe a random effect block bootstrap approach for clustered data that is simple to implement, free of both the distribution and the dependence assumptions of the parametric bootstrap and is consistent when the mixed model assumptions are valid. Results based on …


The Effect Of Cooling Rates On The Microstructure And Mechanical Properties Of Thermo-Mechanically Processed Ti-Al-Mo-V-Cr-Fe Alloys, Mansur Ahmed, Dmytro G. Savvakin, Orest M. Ivasishin, Elena V. Pereloma Jan 2013

The Effect Of Cooling Rates On The Microstructure And Mechanical Properties Of Thermo-Mechanically Processed Ti-Al-Mo-V-Cr-Fe Alloys, Mansur Ahmed, Dmytro G. Savvakin, Orest M. Ivasishin, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

Two near-β titanium alloys, Ti–5Al–5Mo–5V–1Cr–1Fe and a modified one containing 2 wt% Cr (Ti–5Al–5Mo–5V–2Cr–1Fe) were produced from Ti hydride precursor powders via the cost-effective blended elemental powder metallurgy technique. The effects of two cooling rates (10 K s−1 and 1 K s−1) during thermo-mechanical processing on the microstructure and mechanical properties were investigated using X-ray diffraction and scanning electron microscopy. X-ray line profile analysis revealed that dislocation densities and microstrain in β-Ti phase are higher than in α-Ti phase for all cases. In both alloys, slower cooling results in an increase in α volume fraction and promotes morphology of continuous …


Effect Of Deformation Temperature On Niobium Clustering, Precipitation And Austenite Recrystallisation In A Nb-Ti Microalloyed Steel, Andrii G. Kostryzhev, Abdullah Al Alshahrani, Chen Zhu, Simon P. Ringer, Elena V. Pereloma Jan 2013

Effect Of Deformation Temperature On Niobium Clustering, Precipitation And Austenite Recrystallisation In A Nb-Ti Microalloyed Steel, Andrii G. Kostryzhev, Abdullah Al Alshahrani, Chen Zhu, Simon P. Ringer, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

The effect of deformation temperature on Nb solute clustering, precipitation and the kinetics of austenite recrystallisation were studied in a steel containing 0.081C–0.021Ti–0.064 Nb (wt%). Thermo-mechanical processing was carried out using a Gleeble 3500 simulator. The austenite microstructure was studied using a combination of optical microscopy, transmission electron microscopy, and atom probe microscopy, enabling a careful characterisation of grain size, as well as Nb-rich clustering and precipitation processes. A correlation between the austenite recrystallisation kinetics and the chemistry, size and number density of Nb-rich solute atom clusters, and NbTi(C,N) precipitates was established via the austenite deformation temperature. Specifically, we have …


Effect Of Austenitising And Deformation Temperatures On Dynamic Recrystallisation In Nb-Ti Microalloyed Steel, Andrii G. Kostryzhev, Abdullah Al Shahrani, Chen Zhu, Simon P. Ringer, Elena V. Pereloma Jan 2013

Effect Of Austenitising And Deformation Temperatures On Dynamic Recrystallisation In Nb-Ti Microalloyed Steel, Andrii G. Kostryzhev, Abdullah Al Shahrani, Chen Zhu, Simon P. Ringer, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

An investigation into influence of the austenitising temperature and the austenite deformation temperature on Nb precipitation and recrystallisation kinetics was carried out for a steel containing 0.081C-0.021Ti-0.064Nb (wt. %). The austenite grain structure was correlated to the dispersive properties of Nb atom clustering and precipitation. Irrespective of the austenitising temperature, deformation to 0.75 strain at 1075 °C produced a fully recrystallised microstructure. After deformation at 975 °C, only partial recrystallisation was observed in the samples austenitised at higher temperature, whereas samples austenitised at lower temperature were fully recrystallised. The influence of solute drag and particle pinning effects on the recrystallisation …


Effect Of First Network Topology On The Toughness Of Double Network Hydrogels, Hai Xin, Sureyya Saricilar, Hugh Ralph Brown, Philip G. Whitten, Geoffrey Maxwell Spinks Jan 2013

Effect Of First Network Topology On The Toughness Of Double Network Hydrogels, Hai Xin, Sureyya Saricilar, Hugh Ralph Brown, Philip G. Whitten, Geoffrey Maxwell Spinks

Faculty of Engineering and Information Sciences - Papers: Part A

The fracture toughness of a double network (DN) hydrogel is shown here to be directly proportional to the toughness of the first-formed network. A series of DN gels was prepared in which the cross-link density of the first (tighter) network was controlled by varying the monomer and cross-linker concentrations. The toughness, tensile strength and elastic modulus of the DN gels increased significantly with an increase in the cross-link density of the first network and with identically prepared second networks. Moreover, the toughness of the double network was found to be linearly related to the toughness of the first network with …


Effect Of Particle Properties On The Discrete Element Simulation Of Wall Friction, Andrew Grima, Peter Wypych Jan 2013

Effect Of Particle Properties On The Discrete Element Simulation Of Wall Friction, Andrew Grima, Peter Wypych

Faculty of Engineering and Information Sciences - Papers: Part A

Modelling the interaction between particles and boundaries is of great interest and importance in many Discrete Element Method (DEM) applications where boundary failure conditions dictate the flow behaviour and velocity gradients of a bulk material. Bulk wall friction angles in DEM models are dependent on the mechanical properties of the particles and boundary material as well as the constraints of the contact models used, especially the tangential and rolling torque components. This paper examines the parameters determined from the calibration inclination test by conducting direct wall shear tests to validate the accuracy of the calibration parameters and the sensitivity of …


The Effect Of Chemical Composition On Microstructure And Properties Of Intercritically Reheated Coarse-Grained Heat-Affected Zone In X70 Steels, Zhixiong Zhu, Lenka Kuzmikova, Huijun Li, Frank J. Barbaro Jan 2013

The Effect Of Chemical Composition On Microstructure And Properties Of Intercritically Reheated Coarse-Grained Heat-Affected Zone In X70 Steels, Zhixiong Zhu, Lenka Kuzmikova, Huijun Li, Frank J. Barbaro

Faculty of Engineering and Information Sciences - Papers: Part A

The current study investigates the effect of different levels of Ti, N, and Ti/N ratios on microstructure and properties in the intercritically reheated coarse-grained heat-affected zone (ICCGHAZ) of two-pass submerged arc welds in API 5L grade X70 pipe. Gleeble simulation was employed to reproduce the ICCGHAZ of actual welds. Hardness and Charpy V-notch (CVN) tests were performed on the simulated samples. The microstructure of simulated ICCGHAZ was characterized by optical microscopy and scanning electron microscopy (SEM). LePera color etching technique was employed to identify and quantify the martensitic-austenitic (M-A) constituent. Results show that the simulated ICCGHAZ exhibited extremely low toughness, …


The Joint Effect Of Image Blur And Illumination Distortions For Mobile Visual Search Of Print Media, Yi Cao, Christian Ritz, Raad Raad Jan 2013

The Joint Effect Of Image Blur And Illumination Distortions For Mobile Visual Search Of Print Media, Yi Cao, Christian Ritz, Raad Raad

Faculty of Engineering and Information Sciences - Papers: Part A

Mobile Visual Search (MVS) is an emerging area of research given the explosion of smart and powerful mobile devices. Typically, the performance of MVS applications is influenced by the implemented image processing algorithms as well as various distortions that occur when capturing images by the mobile camera. This paper examines the joint effect of two common distortions, namely the illumination changes and image blurring on image matching accuracy for print media when using four state-of-the art local feature algorithms. Results obtained for a database of real camera images captured by two different camera models show that the illumination changes have …


Automatic Bdi Plan Recognition From Process Execution Logs And Effect Logs, Hongyun Xu, Bastin Tony Roy Savarimuthu, Aditya Ghose, Evan Morrison, Qiying Cao, Youqun Shi Jan 2013

Automatic Bdi Plan Recognition From Process Execution Logs And Effect Logs, Hongyun Xu, Bastin Tony Roy Savarimuthu, Aditya Ghose, Evan Morrison, Qiying Cao, Youqun Shi

Faculty of Engineering and Information Sciences - Papers: Part A

Agent applications are often viewed as unduly expensive to develop and maintain in commercial contexts. Organizations often settle for less sophisticated and more traditional software in place of agent technology because of (often misplaced) fears about the development and maintenance costs of agent technology, and the often mistaken perception that traditional software offers better returns on investment. This paper aims to redress this by developing a plan recognition framework for agent program learning, where behavior logs of legacy applications (or even manually executed processes) are mined to extract a 'draft' version of agent code that could eventually replace these applications …


Effect Of Rice Husk Ash On Workability And Strength Of Concrete, Avinash Babu Srinivasreddy, Timothy J. Mccarthy, Eric Lume Jan 2013

Effect Of Rice Husk Ash On Workability And Strength Of Concrete, Avinash Babu Srinivasreddy, Timothy J. Mccarthy, Eric Lume

Faculty of Engineering and Information Sciences - Papers: Part A

Rice husk ash (RHA) is an agricultural waste which is a pozzolanic material that can be blended with the cement for manufacturing concrete. Its use can reduce the environmental impact of the cement industry. The present study investigates the chemical and morphological nature of RHA and silica fume (SF). Both can be used to improve strength and durability properties of concrete. Particle size distribution, loss on ignition (LOI), X-ray diffraction analysis, scanning electron microscopic were conducted. The effect of replacement of cement 5%, 10% and 15% by weight with SF and RHA on compressive strength and workability has also been …


Effect Of Confining Pressure And Frequency On The Deformation Of Ballast, Pramod Kumar Thakur, Jayan Sylaja Vinod, Buddhima Indraratna Jan 2013

Effect Of Confining Pressure And Frequency On The Deformation Of Ballast, Pramod Kumar Thakur, Jayan Sylaja Vinod, Buddhima Indraratna

Faculty of Engineering and Information Sciences - Papers: Part A

Increasing the speed and frequency of trains with the same static axle weight imparts higher dynamic axle loads more frequently. When this occurs on existing track which has not been designed for such loading there can be increased rates of ballast degradation, characterised by unacceptable deformation and lateral spread, leading to more frequent requirements for track maintenance. Recent studies carried out at the University of Wollongong highlighted that confining pressure and frequency have a significant influence on the permanent deformation and degradation of ballast. However, confinement required to keep the deformation and degradation of the ballasted track to an acceptable …


Effect Of Cooling Rate On Oxidation Behaviour Of Microalloyed Steel, Xianglong Yu, Zhengyi Jiang, Jingwei Zhao, Dongbin Wei, Cunlong Zhou Jan 2013

Effect Of Cooling Rate On Oxidation Behaviour Of Microalloyed Steel, Xianglong Yu, Zhengyi Jiang, Jingwei Zhao, Dongbin Wei, Cunlong Zhou

Faculty of Engineering and Information Sciences - Papers: Part A

Oxidation characteristics of a microalloyed low carbon steel were investigated by a hot rolling mill combined with acceleration cooling system over the cooling rate range from 20 to 70°C/s. The effects of cooling rate after hot rolling on microstructure and phase composition of oxide scale were examined. The results showed that the increase of the cooling rate has a significant influence on the decrease of the grain size and surface roughness of oxide scale. A higher cooling rate promotes the formation of retain wustite and primary magnetite precipitation while suppression of eutectoid α-iron precipitates. This provides the possibility to enhance …


The Effect Of Slag Basicity On Spinal Inclusion Wettability, Hamed Abdeyazdan, Brian J. Monaghan, Neslihan Dogan, M Akbar Rhamdhani Jan 2013

The Effect Of Slag Basicity On Spinal Inclusion Wettability, Hamed Abdeyazdan, Brian J. Monaghan, Neslihan Dogan, M Akbar Rhamdhani

Faculty of Engineering and Information Sciences - Papers: Part A

Steel cleanness is an important and growing research area driven by the demands to produce high quality steel. Inclusion content in steel is an important criterion to assess clean steel. MgO.Ah03 spinel inclusions cause problems in steel processing and are generally deleterious to steel products due to their high melting point and high hardness. Jnclusions are generally r· moved by rea ting with slag. This is primarily achieved by optimizing lhe PI' 'ess omliLions to promote contact and reaction between the inclusion and S,l,lg '. or efticient rem val from the steel the inclusions must attach to and dissolve in …


Confinement Effect Of Frp And Transverse Steel On Retrofitting Square Concrete Columns, Le V. Doan, Xu Lei, Muhammad N. S Hadi, Thong M. Pham Jan 2013

Confinement Effect Of Frp And Transverse Steel On Retrofitting Square Concrete Columns, Le V. Doan, Xu Lei, Muhammad N. S Hadi, Thong M. Pham

Faculty of Engineering and Information Sciences - Papers: Part A

This study presents an experimental investigation into strain distribution of Fibre-Reinforced Polymer (FRP) in FRP-confined concrete columns with internal steel reinforcement under concentric and eccentric loading conditions. A total of nine reinforced concrete columns were cast and tested. Three of them were square in cross-section while the others were originally square but were shape-modified into circular columns with four pieces of segmental circular concrete covers and confined with three layers of CFRP. The nominal compressive strength of the segmental concrete covers was 40 MPa and 80 MPa. All columns were tested under concentric load, 25 mm or 50 mm eccentric …