Open Access. Powered by Scholars. Published by Universities.®
Science and Technology Studies Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 12 of 12
Full-Text Articles in Science and Technology Studies
Structural Evolution Of Electrodes In The Ncr And Cgr Cathode-Containing Commercial Lithium-Ion Batteries Cycled Between 3.0 And 4.5 V: An Operando Neutron Powder-Diffraction Study, Wei Kong Pang, Moshiul Alam, Vanessa K. Peterson, Neeraj Sharma
Structural Evolution Of Electrodes In The Ncr And Cgr Cathode-Containing Commercial Lithium-Ion Batteries Cycled Between 3.0 And 4.5 V: An Operando Neutron Powder-Diffraction Study, Wei Kong Pang, Moshiul Alam, Vanessa K. Peterson, Neeraj Sharma
Faculty of Engineering and Information Sciences - Papers: Part A
The dissimilar lattice-evolution of the isostructural layered Li(Ni,Co,Al)O2 (NCR) and Li(Ni,Co,Mn)O2 (CGR) cathodes in commercial lithium-ion batteries during overcharging/discharging was examined using operando neutron powder-diffraction. The stacking axis (c parameter) of both cathodes expands on initial lithiation and contracts on further lithiation. Although both the initial increase and later decrease are smaller for the CGR cathode, the overall change between battery charged and discharged states of the c parameter is larger for the CGR (1.29%) than for the NCR cathode (0.33%). We find these differences are correlated to the transition metal to oxygen bond (as measured through …
Brittle Versus Ductile Behaviour Of Nanotwinned Copper: A Molecular Dynamics Study, Linqing Pei, Cheng Lu, Xing Zhao, Liang Zhang, Kuiyu Cheng, Guillaume Michal, A Kiet Tieu
Brittle Versus Ductile Behaviour Of Nanotwinned Copper: A Molecular Dynamics Study, Linqing Pei, Cheng Lu, Xing Zhao, Liang Zhang, Kuiyu Cheng, Guillaume Michal, A Kiet Tieu
Faculty of Engineering and Information Sciences - Papers: Part A
Nanotwinned copper (Cu) exhibits an unusual combination of ultra-high yield strength and high ductility. A brittle-to-ductile transition was previously experimentally observed in nanotwinned Cu despite Cu being an intrinsically ductile metal. However, the atomic mechanisms responsible for brittle fracture and ductile fracture in nanotwinned Cu are still not clear. In this study, molecular dynamics (MD) simulations at different temperatures have been performed to investigate the fracture behaviour of a nanotwinned Cu specimen with a single-edge-notched crack whose surface coincides with a twin boundary. Three temperature ranges are identified, indicative of distinct fracture regimes, under tensile straining perpendicular to the twin …
An In-Situ Neutron Diffraction Study Of A Multi-Phase Transformation And Twinning-Induced Plasticity Steel During Cyclic Loading, Ahmed A. Saleh, Donald W. Brown, Elena V. Pereloma, Bjorn Clausen, Christopher H. J Davies, Carlos N. Tome, Azdiar A. Gazder
An In-Situ Neutron Diffraction Study Of A Multi-Phase Transformation And Twinning-Induced Plasticity Steel During Cyclic Loading, Ahmed A. Saleh, Donald W. Brown, Elena V. Pereloma, Bjorn Clausen, Christopher H. J Davies, Carlos N. Tome, Azdiar A. Gazder
Faculty of Engineering and Information Sciences - Papers: Part A
In-situ neutron diffraction during cyclic tension-compression loading (þ3.5% to 2.8%) of a 17Mn-3Al-2Si-1Ni-0.06C steel that exhibits concurrent transformation and twinning -induced plasticity effects indicated a significant contribution of intragranular back stresses to the observed Bauschinger effect. Rietveld analysis revealed a higher rate of martensitic transformation during tension compared to compression. Throughout cycling, a0-martensite exhibited the highest phase strains such that it bears an increasing portion of the macroscopic load as its weight fraction evolves. On the other hand, the e-martensite strain remained compressive as it accommodated most of the internal strains caused by the shape misfit associated with the c!e …
Molecular Dynamics Study On The Grain Boundary Dislocation Source In Nanocrystalline Copper Under Tensile Loading, Liang Zhang, Cheng Lu, A Kiet Tieu, Linqing Pei, Xing Zhao, Kuiyu Cheng
Molecular Dynamics Study On The Grain Boundary Dislocation Source In Nanocrystalline Copper Under Tensile Loading, Liang Zhang, Cheng Lu, A Kiet Tieu, Linqing Pei, Xing Zhao, Kuiyu Cheng
Faculty of Engineering and Information Sciences - Papers: Part A
Grain boundary (GB) is the interface between different oriented crystals of the same material, and it can have a significant effect on the many properties of materials. When the average or entire range of grain size is reduced to less than 100 nm, the conventional plastic deformation mechanisms dominated by dislocation processes become difficult and GBmediated deformation mechanisms become increasingly important. One of the mechanisms that can play a profound role in the strength and plasticity of metallic polycrystalline materials is the heterogeneous nucleation and emission of dislocations from GB. In this study, we conducted molecular dynamics simulations to study …
A Study Of The Behaviour Of Fresh And Coal Fouled Ballast Reinforced By Geogrid Using The Discrete Element Method, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn
A Study Of The Behaviour Of Fresh And Coal Fouled Ballast Reinforced By Geogrid Using The Discrete Element Method, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn
Faculty of Engineering and Information Sciences - Papers: Part A
Geogrids are widely used in ballasted rail tracks for reinforcement and stabilisation. During train operation, ballast becomes contaminated or fouled due to infiltration of fines from the surface, mud pumping from the subgrade, and degradation, which decreases the performance of the geogrids. This paper presents the results of a laboratory and numerical simulation to study the effect that coal fines have on the interface between ballast and geogrid. The stress-strain behaviour of fresh and fouled ballast reinforced by geogrid was investigated via a series of large scale direct shear tests in the laboratory and numerical simulations using the Discrete Element …
3d Bridge Microdosimeter: Charge Collection Study And Application To Rbe Studies In 12C Radiation Therapy, Linh T. Tran, Dale A. Prokopovich, Susanna Guatelli, Marco Petasecca, Michael L. F Lerch, Mark I. Reinhard, Anatoly B. Rosenfeld
3d Bridge Microdosimeter: Charge Collection Study And Application To Rbe Studies In 12C Radiation Therapy, Linh T. Tran, Dale A. Prokopovich, Susanna Guatelli, Marco Petasecca, Michael L. F Lerch, Mark I. Reinhard, Anatoly B. Rosenfeld
Faculty of Engineering and Information Sciences - Papers: Part A
Radiotherapy using heavy ion beam such as Carbon-ion has the advantage for the treatment of deep-seated tumour over conventional radiotherapy with X-rays due to an enhanced dose deposition in the Bragg peak (BP) at the end of the ion range. The highest dose can be deposited in the tumour with much lower doses to the surrounding healthy tissue. The Relative Biological Effectiveness (RBE) of a carbon-ion radiotherapy beam greatly depends on a depth of the target volume in the body and the nuclear fragmentation process that increases close to the BP or spread out BP (SOBP) as well as neutrons. …
Comparison Of Oncentra ® Brachy Ipsa And Graphical Optimisation Techniques: A Case Study Of Hdr Brachytherapy Head And Neck And Prostate Plans, Michael Jameson, Lucy Ohanessian, Vikneswary Batumalai, Virendra Patel, Lois C. Holloway
Comparison Of Oncentra ® Brachy Ipsa And Graphical Optimisation Techniques: A Case Study Of Hdr Brachytherapy Head And Neck And Prostate Plans, Michael Jameson, Lucy Ohanessian, Vikneswary Batumalai, Virendra Patel, Lois C. Holloway
Faculty of Engineering and Information Sciences - Papers: Part A
There are a number of different dwell positions and time optimisation options available in the Oncentra® Brachy (Elekta Brachytherapy Solutions, Veenendaal, The Netherlands) brachytherapy treatment planning system. The purpose of this case study was to compare graphical (GRO) and inverse planning by simulated annealing (IPSA) optimisation techniques for interstitial head and neck (HN) and prostate plans considering dosimetry, modelled radiobiology outcome and planning time. Four retrospective brachytherapy patients were chosen for this study, two recurrent HN and two prostatic boosts. Manual GRO and IPSA plans were generated for each patient. Plans were compared using dose-volume histograms (DVH) and dose …
A Survey And Study Of Planar Antennas For Pico-Satellites, Faisel Em M Tubbal, Raad Raad, Kwan-Wu Chin
A Survey And Study Of Planar Antennas For Pico-Satellites, Faisel Em M Tubbal, Raad Raad, Kwan-Wu Chin
Faculty of Engineering and Information Sciences - Papers: Part A
Works on pico-satellites have gained momentum recently, especially those that consider pico-satellites as part of a much larger constellation or swarm. This feature allows pico-satellites to provide high temporal resolution of observational data and redundancy. In particular, it reduces the need for satellite-to-ground communications and, hence, helps save energy and allows the execution of distributed processing algorithms on the satellites themselves. Consequently, satellite-to-satellite or cross-link communication is critical. To realize these advantages, the cross-link antenna employed on pico-satellites must meet many criteria, namely, small size, lightweight, low-power consumption, high gain, wide bandwidth, circular polarization, and beam steerability. To date, no …
Study Of The Consequences Of Co2 Released From High-Pressure Pipelines, Xiong Liu, Ajit R. Godbole, Cheng Lu, Guillaume Michal, Phillip Venton
Study Of The Consequences Of Co2 Released From High-Pressure Pipelines, Xiong Liu, Ajit R. Godbole, Cheng Lu, Guillaume Michal, Phillip Venton
Faculty of Engineering and Information Sciences - Papers: Part A
The development of the Carbon Capture and Storage (CCS) technique requires an understanding of the hazards posed by the operation of high-pressure CO2 pipelines. To allow the appropriate safety precautions to be taken, a comprehensive understanding of the consequences of unplanned CO2 releases is essential before the deployment of CO2 pipelines. In this paper, we present models for the predictions of discharge rate, atmospheric expansion and dispersion due to accidental CO2 releases from high-pressure pipelines. The GERG-2008 Equation of State (EOS) was used in the discharge and expansion models. This enabled more precise 'source strength' predictions. …
Study On Surface Asperity Flattening In Cold Quasi-Static Uniaxial Planar Compression By Crystal Plasticity Finite Element Method, Hejie Li, Zhengyi Jiang, Dongbin Wei, Jianzhong Xu, Xiaoming Zhang, Dianyao Gong, Jingtao Han
Study On Surface Asperity Flattening In Cold Quasi-Static Uniaxial Planar Compression By Crystal Plasticity Finite Element Method, Hejie Li, Zhengyi Jiang, Dongbin Wei, Jianzhong Xu, Xiaoming Zhang, Dianyao Gong, Jingtao Han
Faculty of Engineering and Information Sciences - Papers: Part A
In order to study the surface asperity flattening in a quasi-static cold uniaxial planar compression, the experimental results of atomic force microscope and electron backscattered diffraction have been employed in a ratedependent crystal plasticity model to analyze this process. The simulation results show a good agreement with the experimental results: in this quasi-static deformation process, lubrication can hinder the surface asperity flattening process even under very low deformation rate. However, due to the limitation of the model and some parameters, the simulation results cannot predict all the properties in detail such as S orientation {123}and the maximum stress in sample …
Experimental And Numerical Study Of Micro Deep Drawing, Liang Luo, Zhengyi Jiang, Dongbin Wei, Kenichi Manabe, Hideki Sato
Experimental And Numerical Study Of Micro Deep Drawing, Liang Luo, Zhengyi Jiang, Dongbin Wei, Kenichi Manabe, Hideki Sato
Faculty of Engineering and Information Sciences - Papers: Part A
Micro forming is a key technology for an industrial miniaturisation trend, and micro deep drawing (MDD) is a typical micro forming method. It has great advantages comparing to other micro manufacturing methods, such as net forming ability, mass production potential, high product quality and complex 3D metal products fabrication capacity. Meanwhile, it is facing difficulties, for example the so-called size effects, once scaled down to micro scale. To investigate and to solve the problems in MDD, a combined micro blanking-drawing machine is employed and an explicit-implicit micro deep drawing model with a voronoi blank model is developed. Through heat treatment …
The Role Of Pyrimidine And Water As Underlying Molecular Constituents For Describing Radiation Damage In Living Tissue: A Comparative Study, Martina C. Fuss, L Ellis-Gibbings, Darryl B. Jones, M J. Brunger, Francisco Blanco, A Muñoz, Paulo Limao-Vieira, Gustavo Garcia
The Role Of Pyrimidine And Water As Underlying Molecular Constituents For Describing Radiation Damage In Living Tissue: A Comparative Study, Martina C. Fuss, L Ellis-Gibbings, Darryl B. Jones, M J. Brunger, Francisco Blanco, A Muñoz, Paulo Limao-Vieira, Gustavo Garcia
Faculty of Engineering and Information Sciences - Papers: Part A
Water is often used as the medium for characterizing the effects of radiation on living tissue. However, in this study, charged-particle track simulations are employed to quantify the induced physicochemical and potential biological implications when a primary ionising particle with energy 10 keV strikes a medium made up entirely of water or pyrimidine. Note that pyrimidine was chosen as the DNA/RNA bases cytosine, thymine, and uracil can be considered pyrimidine derivatives. This study aims to assess the influence of the choice of medium on the charged-particle transport, and identify how appropriate it is to use water as the default medium …