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University of Wollongong

Faculty of Engineering - Papers (Archive)

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Full-Text Articles in Engineering

Evolution Of The Illawarra Escarpment Terrain, Phillip Flentje Jan 2012

Evolution Of The Illawarra Escarpment Terrain, Phillip Flentje

Faculty of Engineering - Papers (Archive)

Drawing on the disciplines of stratigraphy, plate tectonics and passive margin development, the evolution of IIIawarra Escarpment terrain in the southeastern corner of the Sydney Basin is placed within known geological constraints. The development of the terrain begins with the initial deposition of the early Permian Sydney Basin sequences, into what was a developing (yet subsequently failed) rift fracture within the eastern side of the Gondwana supercontinent (the Sydney - Gunnedah - Bowen Basin trough), through to the eventual rifting of the existing continental margin and opening of the Tasman Sea around 70 million years ago in the vicinity of …

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"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 Jan 2012

"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 …

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A Novel Model To Measure Supplier Performance In The Supplier Selection Process, Alptekin Ulutas, Senevi Kiridena, Peter Gibson Jan 2012

A Novel Model To Measure Supplier Performance In The Supplier Selection Process, Alptekin Ulutas, Senevi Kiridena, Peter Gibson

Faculty of Engineering - Papers (Archive)

Supplier evaluation has become a significant topic over the past decades, as companies have started to become more outsourced oriented. However, previous research on this topic has not paid adequate attention to the limitations associated with availability of accurate and reliable data relating to the performance of potential suppliers. In an attempt to address this issue, this paper proposes a novel supplier evaluation model that can handle imprecise quantitative and qualitative data. Additionally, Decision Maker’s opinions regarding both qualitative and quantitative criteria are incorporated into this model so that a more comprehensive and realistic assessment of supplier performance can be …

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Angular Dependence Of Pinning Potential, Upper Critical Field, And Irreversibility Field In Underdoped Bafe1.9co0.1as2 Single Crystal, Mahboobeh Shahbazi, Xiaolin Wang, S R. Ghorbani, S. X. Dou, K Y. Choi Jan 2012

Angular Dependence Of Pinning Potential, Upper Critical Field, And Irreversibility Field In Underdoped Bafe1.9co0.1as2 Single Crystal, Mahboobeh Shahbazi, Xiaolin Wang, S R. Ghorbani, S. X. Dou, K Y. Choi

Faculty of Engineering - Papers (Archive)

Underdoped BaFe1.9Co0.1As2 single crystal was studied by angular dependence of magneto-transport at fields up to 13 T over a wide range of temperature. Our results show that pinning potential, Uo, decreases slightly for h45 and remains constant for h45, while the upper critical field, Hc2, and the irreversibility field, Hirr, increase with h. According to anisotropic Ginzburg-Landau theory, the anisotropy was determined by scaling the resistivity under different magnetic fields below the superconducting critical temperature, Tc. Anisotropy, C, in the underdoped crystal is found to be temperature dependent and decreases from 2.1 to 1.8 for as T is reduced from …

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Study On A Seawater Hydraulic Piston Pump With Check Valves For Underwater Tools, X He, B Zhu, Y Liu, Z Jiang Jan 2012

Study On A Seawater Hydraulic Piston Pump With Check Valves For Underwater Tools, X He, B Zhu, Y Liu, Z Jiang

Faculty of Engineering - Papers (Archive)

The aim of this study is to develop a seawater hydraulic piston pump for the power pack of an underwater tool system. A pump with check valves and oil–water-separated structure was selected for the purpose of improving its tolerance to particles when applied in open-circuit system. A novel ‘anti-loosening’ structure was introduced for the piston/shoe assembly. To improve the anti-wear and anti-corrosion performances of the piston and sleeve pairs under seawater lubrication, carbon fibre-reinforced polyetheretherketone was injected as an inner of the sleeve, and synthesized WC was formed on the piston with improved surface hardness. The unbalance problem of the …

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Fluctuation Of Mean Free Path And Transition Temperature Induced Vortex Pinning In (Ba,K)Fe2as2 Superconductors, S R. Ghorbani, Xiaolin Wang, Mahboobeh Shahbazi, S. X. Dou, C T. Lin Jan 2012

Fluctuation Of Mean Free Path And Transition Temperature Induced Vortex Pinning In (Ba,K)Fe2as2 Superconductors, S R. Ghorbani, Xiaolin Wang, Mahboobeh Shahbazi, S. X. Dou, C T. Lin

Faculty of Engineering - Papers (Archive)

The vortex pinning mechanisms of Ba0.72K0.28Fe2As2 single crystal have been studied systematically as a function of temperature and magnetic field. The temperature dependence of the critical current density, Jc(T), was analysed within the collective pinning model at different magnetic fields. It was found that both the dl pinning mechanism, i.e., pinning associated with charge-carrier mean free path fluctuation, and the dTc pinning mechanism, which is associated with spatial fluctuations of the transition temperature, coexist in the Ba0.72K0.28Fe2As2 single crystal in fields smaller than 4 T. Their contributions are strongly temperature and magnetic field dependent. At lower temperature and B

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How To Achieve Maximum Charge Carrier Loading On Heteroatom-Substituted Graphene Nanoribbon Edges: Density Functional Theory Study, Ting Liao, Chenghua Sun, Ziqi Sun, Aijun Du, Denisa Hulicova-Jurcakova, Sean C. Smith Jan 2012

How To Achieve Maximum Charge Carrier Loading On Heteroatom-Substituted Graphene Nanoribbon Edges: Density Functional Theory Study, Ting Liao, Chenghua Sun, Ziqi Sun, Aijun Du, Denisa Hulicova-Jurcakova, Sean C. Smith

Faculty of Engineering - Papers (Archive)

The practical number of charge carriers loaded is crucial to the evaluation of the capacity performance of carbon-based electrodes in service, and cannot be easily addressed experimentally. In this paper, we report a density functional theory study of charge carrier adsorption onto zigzag edge-shaped graphene nanoribbons (ZGNRs), both pristine and incorporating edge substitution with boron, nitrogen or oxygen atoms. All edge substitutions are found to be energetically favorable, especially in oxidized environments. The maximal loading of protons onto the substituted ZGNR edges obeys a rule of [8-n- 1], where n is the number of valence electrons of the edge-site atom …

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Microstructure-Property Relationship In The Thermomechanically Processed C-Mn-Si-Nb-Al-(Mo) Transformation-Induced Plasticity Steels Before And After Prestraining And Bake Hardening Treatment, I B. Timokhina, M Enomoto, M K. Miller, E V. Pereloma Jan 2012

Microstructure-Property Relationship In The Thermomechanically Processed C-Mn-Si-Nb-Al-(Mo) Transformation-Induced Plasticity Steels Before And After Prestraining And Bake Hardening Treatment, I B. Timokhina, M Enomoto, M K. Miller, E V. Pereloma

Faculty of Engineering - Papers (Archive)

The effect of prestraining and bake hardening (PS/BH) on the development of microstructures and mechanical properties in thermomechanically processed transformation-induced plasticity (TRIP) steels with additions of Nb, Mo, and Al was studied by atom probe tomography (APT) and transmission electron microscopy (TEM). An increase in number density and sizes of clusters and nanoscale precipitates was observed in both steels but was more significant in the Nb-Al-Mo steel than in the Nb-Al steel. This increase could be explained by the possible fast diffusion of Nb and Mo atoms at low temperatures, as was observed for surface diffusivity. The contributions of cluster …

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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 Jan 2012

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 …

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Introduction To The Sydney Soil Model, Martin D. Liu, John P. Carter, David W. Airey Jan 2012

Introduction To The Sydney Soil Model, Martin D. Liu, John P. Carter, David W. Airey

Faculty of Engineering - Papers (Archive)

In this paper a new constitutive model recently suggested by the authors, referred to as the Sydney Soil model, is introduced. The Sydney Soil Model is formulated within the framework of Critical State Soil Mechanics and is suitable for describing the behaviour of structured soils including both clays and sands. In the proposed model, the mechanical behaviour of soil is divided into two parts, that at a reference state and that attributed to the influence of soil structure. The reference state behaviour is formulated according to the soil properties at the critical state of deformation, based on the concept of …

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Comparative Behaviour Of Frp Confined Square Concrete Columns Under Eccentric Loading, X Lei, Thong M. Pham, M N. S Hadi Jan 2012

Comparative Behaviour Of Frp Confined Square Concrete Columns Under Eccentric Loading, X Lei, Thong M. Pham, M N. S Hadi

Faculty of Engineering - Papers (Archive)

This study evaluates different methods of strengthening existing square concrete columns under eccentric loading. Sixteen reinforced square concrete columns were cast. The columns were made from normal strength concrete and the reinforcement was kept at minimum simulating columns needing retrofitting. Four columns were modified with round comers and wrapped with three layers of CFRP, four were circularised by circular segments and wrapped with three layers of CFRP, and the last four columns were circularised and confined with steel straps. Specimens from each group were tested under concentric, eccentric (15 or 25 mm) and flexural bending. Results from the study showed …

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The Effect Of Reduced Graphene Oxide Addition On The Superconductivity Of Mgb2, K S. B De Silva, S Gambhir, Xiaolin Wang, X Xu, W X. Li, David L. Officer, D Wexler, G G. Wallace, S. X. Dou Jan 2012

The Effect Of Reduced Graphene Oxide Addition On The Superconductivity Of Mgb2, K S. B De Silva, S Gambhir, Xiaolin Wang, X Xu, W X. Li, David L. Officer, D Wexler, G G. Wallace, S. X. Dou

Faculty of Engineering - Papers (Archive)

Reduced graphene oxide (rGO) and highly reduced chemically converted graphene (ICCO) samples were prepared under different processing condition! and were doped into MgBz by a diffusion process at 800 °C for 10 houn. It was demonstrated that a small addition rCCG can significantly improve the supcn;onducting properties of MgBz. Doping of M8B2 with 1 mol% of rCCG resulted in a Ie of 5.45 X lOS A cm-2 at 20 K in self-fields, which il nearly 32% improvement over that of the undopcd sample. This is a significant improvement as most carbon sources adversely affect the Ie performance: at the zero …

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Decision Support: Informing Flood Management, R Laine, C Cook, B Lemass Jan 2012

Decision Support: Informing Flood Management, R Laine, C Cook, B Lemass

Faculty of Engineering - Papers (Archive)

This paper describes the development of a new flood management decision support system which significantly improves the ability of flood practitioners to: 1) Identify adaptation and mitigation solutions to flood inundation; 2) Facilitate objective community flood risk management consultation and 3) Justify floodplain management decisions in a transparent and structured manner to all stakeholders. The nature of a Decision Support System (DSS) and its place in floodplain management is described and it is shown how a DSS can be used as a practical tool to identify options available to flood management practitioners. The new flood management system presented in this …

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Dyni2mn—Magnetisation And Mössbauer Spectroscopy, Jianli Wang, Stewart James Campbell, Shane Joseph Kennedy, S. X. Dou, Guang Heng Wu Jan 2012

Dyni2mn—Magnetisation And Mössbauer Spectroscopy, Jianli Wang, Stewart James Campbell, Shane Joseph Kennedy, S. X. Dou, Guang Heng Wu

Faculty of Engineering - Papers (Archive)

The physical properties of DyNi2Mn doped with 57Fe have been investigated by X-ray diffraction, magnetisation (10–300 K) and 57Fe Mössbauer spectroscopy measurements (5–300 K). DyNi2Mn(57Fe) crystallizes in the MgCu2-type cubic structure (Fd−3m space group). The ordering temperature is found to be TC = 99(2) K, much higher than those of DyNi2 (∼22 K) and DyMn2 (∼35 K). Analyses of isothermal M–H curves and the related Arrott plots confirm that the magnetic phase transition at TC is second order. The magnetic entropy change around TC is 4.0 J/kg K for a magnetic field change of 0 T to 5 T. The …

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Microstructural Evolution During Gaseous Hydrogen Charging Of Zircaloy-4 Processed By High-Pressure Torsion: A Comparative Study, Zhiyang Wang, Huijun Li, Ulf Garbe, Mark D. Callaghan, Yanbo Wang, Xiaozhou Liao Jan 2012

Microstructural Evolution During Gaseous Hydrogen Charging Of Zircaloy-4 Processed By High-Pressure Torsion: A Comparative Study, Zhiyang Wang, Huijun Li, Ulf Garbe, Mark D. Callaghan, Yanbo Wang, Xiaozhou Liao

Faculty of Engineering - Papers (Archive)

The original and high-pressure torsion (HPT) processed Zircaloy-4 materials were hydrided using gaseous hydrogen charging at different hydrogen pressures (10, 15 and 20 atm). The phase and microstructural evolutions of the samples during hydriding were characterized. It showed that when hydriding at the identical conditions, more hydrides tended to form in the HPT samples compared to that of the original ones. At a hydrogen pressure of 20 atm, the HPT sample was completely converted to ε-ZrH2 while some δ-ZrH1.66 hydrides (volume fraction ~5.73%) were present in the material without HPT preprocessing. The HPT samples exhibited high potential for the hydride …

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Terahertz Surfoluminescence, D L. Cortie, R A. Lewis Jan 2012

Terahertz Surfoluminescence, D L. Cortie, R A. Lewis

Faculty of Engineering - Papers (Archive)

The cleaving of a solid to form two new surfaces may result in the emission of light. Conventional mechanoluminescence involves the transfer of charge between the two surfaces. We now demonstrate that the ultra-fast separation of charge within a newly-formed surface will lead to the emission of electromagnetic radiation. In contrast to the visible light previously observed and modeled, the intra-surface radiation contains terahertz frequencies. This newmechanism – named here surfoluminescence – introduces a new class of terahertz-frequency emitters. It also may in part explain the recent observation of terahertz emission from peeling adhesive tape.

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Continuous Sorting Of Microparticles Using Dielectrophoresis, D F. Chen, W H. Li, H Du, M Li Jan 2012

Continuous Sorting Of Microparticles Using Dielectrophoresis, D F. Chen, W H. Li, H Du, M Li

Faculty of Engineering - Papers (Archive)

Sorting of particles such as cells is a critical process for many biomedical applications, and it is challenging to integrate it into an analytical microdevice. We report an effective and flexible dielectrophoresis (DEP)-based microfluidic device for continuous sorting of multiple particles in a microchannel. The particle sorter is composed of two components—a DEP focusing unit and a Movable DEP Trap (MDT). The trap is formed by an array of microelectrodes at the bottom of the channel and a transparent electrode plate placed at the top. The location of the trap is dependent on the configuration of voltages on the array …

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Vertical Drains, Vacuum Consolidation & Preloading, Buddhima Indraratna Jan 2012

Vertical Drains, Vacuum Consolidation & Preloading, Buddhima Indraratna

Faculty of Engineering - Papers (Archive)

Due to the rapid increase in population, and the subsequent industrial and construction boom, especially in the urban and coastal regions, many countries have intensified the inevitable need for developing infrastructure on problematic soils, including soft compressible clays and deposits with low bearing capacities. Moreover, good quality geological materials for construction are also becoming scarce, a problem exacerbated by the numerous environmental constraints imposed in various countries. Because of these reasons, and environmental restrictions on certain public works, ground improvement has now become an integrated and essential component of infrastructure development. Consequently, civil engineers are forced to utilise even the …

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Terahertz Photon Mixing Effect In Gapped Graphene, Yee Sin Ang, Shareef Sultan, Asya Tawfiq, Juncheng Cao, Chao Zhang Jan 2012

Terahertz Photon Mixing Effect In Gapped Graphene, Yee Sin Ang, Shareef Sultan, Asya Tawfiq, Juncheng Cao, Chao Zhang

Faculty of Engineering - Papers (Archive)

We theoretically calculate the terahertz waves mixing effect in doped graphene with a finite bandgap. The temperature dependence of the nonlinear intraband optical response at bandgap opening of few tens of meVare investigated. When the external electric field is weak, a moderate level of bandgap opening is found to slightly enhance the nonlinear optical response. The optical response is however significantly altered under strong-field condition. The strong-field nonlinear optical conductivity exhibits two distinct response ‘hot spot’: (i) low temperature with large bandgap and (ii) high temperature with small bandgap. The electric field required for the nonlinear response to dominate over …

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Isomerization Mechanism Of The Hcred Fluorescent Protein Chromophore, Qiao Sun, Zhen Li, Zhenggang Lan, Christoph Pfisterer, Markus Doerr, Stefan Fischer, Sean C. Smith, Walter Thiel Jan 2012

Isomerization Mechanism Of The Hcred Fluorescent Protein Chromophore, Qiao Sun, Zhen Li, Zhenggang Lan, Christoph Pfisterer, Markus Doerr, Stefan Fischer, Sean C. Smith, Walter Thiel

Faculty of Engineering - Papers (Archive)

To understand how the protein achieves fluorescence, the isomerization mechanism of the HcRed chromophore is studied both under vacuum and in the solvated red fluorescent protein. Quantum mechanical (QM) and quantum mechanical/molecular mechanical (QM/MM) methods are applied both for the ground and the first excited state. The photoinduced processes in the chromophore mainly involve torsions around the imidazolinone-bridge bond (t) and the phenoxy-bridge bond (j). Under vacuum, the isomerization of the cis–trans chromophore essentially proceeds by t twisting, while the radiationless decay requires j torsion. By contrast, the isomerization of the cis–trans chromophore in HcRed occurs via simultaneous t and …

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Comparison Between Experimental And Predicted Conveyor Belt Trajectories, David B. Hastie, Peter W. Wypych Jan 2012

Comparison Between Experimental And Predicted Conveyor Belt Trajectories, David B. Hastie, Peter W. Wypych

Faculty of Engineering - Papers (Archive)

Belt conveyors are commonly used in a multitude of industries to transport material from one location to another. Belt conveyors can be configured in many ways, from a single run which might form a stockpile, to many interconnected belt conveyors, necessitating the use of transfers to successfully deliver material through the system. Whichever method applies, the way in which material leaves the head of a conveyor will dictate the path the flow of material takes to the next step in the process. Many installations run successfully with systems that have been in operation for many years, however not all have …

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A Multi-Institution Evaluation Of Deformable Image Registration Algorithms For Automatic Organ Delineation In Adaptive Head And Neck Radiotherapy, Nicholas Hardcastle, Wolfgang A. Tome, Donald M. Cannon, Charlotte L. Brouwer, Paul W. H Wittendorp, Nesrin Dogan, Matthias Guckenberger, Stephane Allaire, Yogish Mallya, Prashant Kumar, Markus Oechsner, Anne Richter, Shiyu Song, Michael Myers, Bulent Polat, Karl Bzdusek Jan 2012

A Multi-Institution Evaluation Of Deformable Image Registration Algorithms For Automatic Organ Delineation In Adaptive Head And Neck Radiotherapy, Nicholas Hardcastle, Wolfgang A. Tome, Donald M. Cannon, Charlotte L. Brouwer, Paul W. H Wittendorp, Nesrin Dogan, Matthias Guckenberger, Stephane Allaire, Yogish Mallya, Prashant Kumar, Markus Oechsner, Anne Richter, Shiyu Song, Michael Myers, Bulent Polat, Karl Bzdusek

Faculty of Engineering - Papers (Archive)

Background: Adaptive Radiotherapy aims to identify anatomical deviations during a radiotherapy course and modify the treatment plan to maintain treatment objectives. This requires regions of interest (ROIs) to be defined using the most recent imaging data. This study investigates the clinical utility of using deformable image registration (DIR) to automatically propagate ROIs.

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Why Do We Need New Inclusion Experimental Techniques?, Neslihan Dogan, Brian J. Monaghan, Raymond J. Longbottom, Mark H. Reid, Xenophon C. Tsekouras Jan 2012

Why Do We Need New Inclusion Experimental Techniques?, Neslihan Dogan, Brian J. Monaghan, Raymond J. Longbottom, Mark H. Reid, Xenophon C. Tsekouras

Faculty of Engineering - Papers (Archive)

There is an ever increasing demand for cleaner steels, that is, those with low oxide inclusion content. This demand has highlighted the limitations of our current knowledge in controlling and predicting inclusion development during liquid steel processing.1) The formation of inclusions during liquid steel refining is an unavoidable consequence of the current industrial steelmaking process. Steel leaving a steelmaking converter contains anything from 400-1000 ppm of oxygen in solution [O].2) The [O] concentration needs to be reduced to less than 30 ppm to be cast. If not, it will react on solidification producing gas and condensed oxides. If cast in …

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Application Of Centroidal Voronoi Diagram In Numerical Model Of Microforming Process, Hai Na Lu, Dong Bin Wei, Zheng Yi Jiang Jan 2012

Application Of Centroidal Voronoi Diagram In Numerical Model Of Microforming Process, Hai Na Lu, Dong Bin Wei, Zheng Yi Jiang

Faculty of Engineering - Papers (Archive)

Grain size, shape and orientation play an important role on the deformability of micro workpiece as the geometrical dimensions approach to a characteristic scale in micro-forming process. This paper addresses the three-dimensional (3D) finite element (FE) model with weighed centroidal voronoi diagram (WCVD). Steady-state grains are generated when the voronoi generating points approach the grain centroid utilising a simplex integration algorithm. As a result of the centroidal process, the topological features of grains advance the uniform and steady state gradually, which may cause a decrease of interfacial energy. The grain size distribution is compared between the 3D domain and random …

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"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 Jan 2012

"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]"

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Evolutionary Algorithm For Water Storage Forecasting Response To Climate Change With Small Data Sets: The Wolonghu Wetland, China, Qingwei Ni, Li Wang, Binghui Zheng, Muttucumaru Sivakumar Jan 2012

Evolutionary Algorithm For Water Storage Forecasting Response To Climate Change With Small Data Sets: The Wolonghu Wetland, China, Qingwei Ni, Li Wang, Binghui Zheng, Muttucumaru Sivakumar

Faculty of Engineering - Papers (Archive)

"A novel genetic programming (GP) technique, a new method of evolutionary algorithms, was applied to a small data set to predict the water storage of Wolonghu wetland in response to the climate change in the northeastern part of China. Fourteen years (1993-2006) of annual water storage and climatic data of the wetland were used for model training and testing. Results of simulations and predictions illustrate a good fit between calculated water storage and observed values (mean absolute percent error = 9.47, r = 0.99). By comparison, a multilayer perceptron method (a popular artificial neural network model) and Grey theory model …

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A "Skeleton/Skin"Strategy For Preparing Ultrathin Free-Standing Single-Walled Carbon Nanotube/Polyaniline Films For High Performance Supercapacitor Electrodes, Zhiqiang Niu, Pingshan Luan, Qi Shao, Haibo Dong, Jinzhu Li, Jun Chen, Duan Zhao, Le Cai, Weiya Zhou, Xiaodong Chen, Sishen Xie Jan 2012

A "Skeleton/Skin"Strategy For Preparing Ultrathin Free-Standing Single-Walled Carbon Nanotube/Polyaniline Films For High Performance Supercapacitor Electrodes, Zhiqiang Niu, Pingshan Luan, Qi Shao, Haibo Dong, Jinzhu Li, Jun Chen, Duan Zhao, Le Cai, Weiya Zhou, Xiaodong Chen, Sishen Xie

Faculty of Engineering - Papers (Archive)

One of the most critical aspects in the preparation of single-walled carbon nanotubes (SWCNTs)/ conducting polymer hybrid electrodes is to improve the energy density without seriously deteriorating their high power capability. Here, we report a ‘‘skeleton/skin’’ strategy for the preparation of freestanding, thin and flexible SWCNT/polyaniline (PANI) hybrid films by a simple in situ electrochemical polymerization method using directly grown SWCNT films with a continuous reticulate structure as template. In situ electrochemical polymerization can achieve effective deposition of PANI onto the surface of SWCNT bundles in the films and control the morphology and microstructure of the SWCNT/PANI hybrid films. In …

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Development Of A Metallurgical Coke Analogue To Investigate The Effects Of Coke Mineralogy On Coke Reactivity, Raymond Longbottom, Brian J. Monaghan, Oliver Scholes, Merrick R. Mahoney Jan 2012

Development Of A Metallurgical Coke Analogue To Investigate The Effects Of Coke Mineralogy On Coke Reactivity, Raymond Longbottom, Brian J. Monaghan, Oliver Scholes, Merrick R. Mahoney

Faculty of Engineering - Papers (Archive)

In this study the suitability of a laboratory analogue for coke for studying the effects of minerals on the reactivity of coke was evaluated. In addition to this, the effects of different physical properties and production conditions on the reactivity of the coke analogue were also tested. The coke analogue was used for control testing of specific mineral, and to some degree maceral, effects on reactivity. Such information would improve our fundamental understanding of coke reactivity behaviour and could be used to develop more accurate predictive models of coke strength after reaction (CSR) or associated indices and coke properties. The …

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N-Nitrosamine Removal By Reverse Osmosis For Indirect Potable Water Reuse – A Critical Review Based On Observations From Laboratory, Pilot And Full-Scale Studies, Takahiro Fujioka, Stuart J. Khan, Yvan Poussade, Jorg E. Drewes, Long D. Nghiem Jan 2012

N-Nitrosamine Removal By Reverse Osmosis For Indirect Potable Water Reuse – A Critical Review Based On Observations From Laboratory, Pilot And Full-Scale Studies, Takahiro Fujioka, Stuart J. Khan, Yvan Poussade, Jorg E. Drewes, Long D. Nghiem

Faculty of Engineering - Papers (Archive)

N-nitrosodimethylamine (NDMA) and several other N-nitrosamines have been identified as probable human carcinogens. Here, we review key aspects related to the occurrence and removal of N-nitrosamines by reverse osmosis (RO) membranes in the context of indirect potable water reuse. A comprehensive analysis of the existing data reveals significant variations in the rejection of NDMA by RO membranes reported in the literature, ranging from negligible up to 86%. This review article provides some insight into the reasons for such variations by examining the available data on the effects of operating conditions on NDMA rejection. Amongst several operating parameters investigated so far …

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Ultrafast Dynamics Of The Mn3+ D-D Transition And Spin-Lattice Interaction In Ymno3 Film, Z Jin, Hong Ma, Gaofang Li, Y Xu, G Ma, Zhenxiang Cheng Jan 2012

Ultrafast Dynamics Of The Mn3+ D-D Transition And Spin-Lattice Interaction In Ymno3 Film, Z Jin, Hong Ma, Gaofang Li, Y Xu, G Ma, Zhenxiang Cheng

Faculty of Engineering - Papers (Archive)

"We investigate the photo-induced carrier dynamics and spin-lattice interaction in hexagonal YMnO(3) film by the temperature-dependent femtosecond pump-probe spectroscopy. The spin-lattice interaction is identified from the slow component of the transient transmittance change with the excitation energies tuned to 1.7 eV and 2.0 eV, which are close to Mn(3+) ions d((xz),(yz)) d((z2)) and d((x2-y2),(xy)) d((z2)) transition, respectively. Temperature dependences of the spin-lattice relaxation parameters demonstrate that the spin-lattice interaction is strongly connected with the d-d transition within Mn(3+) ions and enhanced by spin ordering. (C) 2012 American Institute of Physics. [doi: 10.1063/1.3675906]"

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