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Full-Text Articles in Physical Sciences and Mathematics

Optimization Of Ported Cfd Kernels On Intel Data Center Gpu Max 1550 Using Oneapi Esimd, Mohammad Zubair, Aaron Walden, Gabriel Nastac, Eric Nielsen, Christoph Bauinger, Xiao Zhu Jan 2023

Optimization Of Ported Cfd Kernels On Intel Data Center Gpu Max 1550 Using Oneapi Esimd, Mohammad Zubair, Aaron Walden, Gabriel Nastac, Eric Nielsen, Christoph Bauinger, Xiao Zhu

Computer Science Faculty Publications

We describe our experience porting FUN3D’s CUDA-optimized kernels to Intel oneAPI SYCL.We faced several challenges, including foremost the suboptimal performance of the oneAPI code on Intel’s new data center GPU. Suboptimal performance of the oneAPI code was due primarily to high register spills, memory latency, and poor vectorization. We addressed these issues by implementing the kernels using Intel oneAPI’s Explicit SIMD SYCL extension (ESIMD) API. The ESIMD API enables the writing of explicitly vectorized kernel code, gives more precise control over register usage and prefetching, and better handles thread divergence compared to SYCL. The ESIMD code outperforms the optimized SYCL …


Faster Multidimensional Data Queries On Infrastructure Monitoring Systems, Yinghua Qin, Gheorghi Guzun Feb 2022

Faster Multidimensional Data Queries On Infrastructure Monitoring Systems, Yinghua Qin, Gheorghi Guzun

Faculty Research, Scholarly, and Creative Activity

The analytics in online performance monitoring systems have often been limited due to the query performance of large scale multidimensional data. In this paper, we introduce a faster query approach using the bit-sliced index (BSI). Our study covers multidimensional grouping and preference top-k queries with the BSI, algorithms design, time complexity evaluation, and the query time comparison on a real-time production performance monitoring system. Our research work extended the BSI algorithms to cover attributes filtering and multidimensional grouping. We evaluated the query time with the single attribute, multiple attributes, feature filtering, and multidimensional grouping. To compare with the existing prior …


Challenges In Covid-19 Chest X-Ray Classification: Problematic Data Or Ineffective Approaches?, Muhammad Ridzuan, Ameera Ali Bawazir, Ivo Gollini Navarrete, Ibrahim Almakky, Mohammad Yaqub Jan 2022

Challenges In Covid-19 Chest X-Ray Classification: Problematic Data Or Ineffective Approaches?, Muhammad Ridzuan, Ameera Ali Bawazir, Ivo Gollini Navarrete, Ibrahim Almakky, Mohammad Yaqub

Computer Vision Faculty Publications

The value of quick, accurate, and confident diagnoses cannot be undermined to mitigate the effects of COVID-19 infection, particularly for severe cases. Enormous effort has been put towards developing deep learning methods to classify and detect COVID-19 infections from chest radiography images. However, recently some questions have been raised surrounding the clinical viability and effectiveness of such methods. In this work, we carry out extensive experiments on a large COVID-19 chest X-ray dataset to investigate the challenges faced with creating reliable solutions from both the data and machine learning perspectives. Accordingly, we offer an in-depth discussion into the challenges faced …


Is Contrastive Learning Suitable For Left Ventricular Segmentation In Echocardiographic Images?, Mohamed Saeed, Rand Muhtaseb, Mohammad Yaqub Jan 2022

Is Contrastive Learning Suitable For Left Ventricular Segmentation In Echocardiographic Images?, Mohamed Saeed, Rand Muhtaseb, Mohammad Yaqub

Computer Vision Faculty Publications

Contrastive learning has proven useful in many applications where access to labelled data is limited. The lack of annotated data is particularly problematic in medical image segmenta-tion as it is difficult to have clinical experts manually annotate large volumes of data. One such task is the segmentation of cardiac structures in ultrasound images of the heart. In this paper, we argue whether or not contrastive pretraining is helpful for the segmentation of the left ventricle in echocardiography images. Furthermore, we study the effect of this on two segmentation networks, DeepLabV3, as well as the commonly used segmentation net-work, UNet. Our …


Predicting Pair Success In A Pair Programming Eye Tracking Experiment Using Cross-Recurrence Quantification Analysis, Maureen M. Villamor, Maria Mercedes T. Rodrigo Jan 2022

Predicting Pair Success In A Pair Programming Eye Tracking Experiment Using Cross-Recurrence Quantification Analysis, Maureen M. Villamor, Maria Mercedes T. Rodrigo

Department of Information Systems & Computer Science Faculty Publications

Pair programming is a model of collaborative learning. It has become a well-known pedagogical practice in teaching introductory programming courses because of its potential benefits to students. This study aims to investigate pair patterns in the context of pair program tracing and debugging to determine what characterizes collaboration and how these patterns relate to success, where success is measured in terms of performance task scores. This research used eye-tracking methodologies and techniques such as cross-recurrence quantification analysis. The potential indicators for pair success were used to create a model for predicting pair success. Findings suggest that it is possible to …


Event-Driven Servers Using Asynchronous, Non-Blocking Network I/O: Performance Evaluation Of Kqueue And Epoll, Lorcan Leonard Jan 2021

Event-Driven Servers Using Asynchronous, Non-Blocking Network I/O: Performance Evaluation Of Kqueue And Epoll, Lorcan Leonard

Dissertations

This research project evaluates the performance of kqueue and epoll in the context of event-driven servers. The evaluation is done through benchmarking and tracing which are used to measure throughput and execution time respectively. The experiment is repeated for both a virtualised and native server environment. The results from the experiment are statistically analysed and compared. These results show significant differences between kqueue and epoll, and a profound impact of virtualisation as a variable.


A Case Study Of Wifi Sniffing Performance Evaluation, Yan Li, Johan Barthelemy, Shuai Sun, Pascal Perez, Bill Moran Jan 2020

A Case Study Of Wifi Sniffing Performance Evaluation, Yan Li, Johan Barthelemy, Shuai Sun, Pascal Perez, Bill Moran

SMART Infrastructure Facility - Papers

Mobile devices regularly broadcast WiFi probe requests in order to discover available proximal WiFi access points for connection. A probe request, sent automatically in the active scanning mode, consisting of the MAC address of the device expresses an advertisement of its presence. A real-time wireless sniffing system is able to sense WiFi packets and analyse wireless traffic. This provides an opportunity to obtain insights into the interaction between the humans carrying the mobile devices and the environment. Susceptibility to loss of the wireless data transmission is an important limitation on this idea, and this is complicated by the lack of …


Structure And Electrochemical Performance Modulation Of A Lini0.8co0.1mn0.1o2 Cathode Material By Anion And Cation Co-Doping For Lithium Ion Batteries, Rong Li, Yong Ming, Wei Xiang, Chunliu Xu, Guilin Feng, Yongchun Li, Yanxiao Chen, Zhenguo Wu, Ben-He Zhong, Xiaodong Guo Jan 2019

Structure And Electrochemical Performance Modulation Of A Lini0.8co0.1mn0.1o2 Cathode Material By Anion And Cation Co-Doping For Lithium Ion Batteries, Rong Li, Yong Ming, Wei Xiang, Chunliu Xu, Guilin Feng, Yongchun Li, Yanxiao Chen, Zhenguo Wu, Ben-He Zhong, Xiaodong Guo

Australian Institute for Innovative Materials - Papers

Ni-rich layered transition metal oxides show great energy density but suffer poor thermal stability and inferior cycling performance, which limit their practical application. In this work, a minor content of Co and B were co-doped into the crystal of a Ni-rich cathode (LiNi0.8Co0.1Mn0.1O2) using cobalt acetate and boric acid as dopants. The results analyzed by XRD, TEM, XPS and SEM reveal that the modified sample shows a reduced energy barrier for Li+ insertion/extraction and alleviated Li+/Ni2+ cation mixing. With the doping of B and Co, corresponding enhanced cycle stability was achieved with a high capacity retention of 86.1% at 1.0C …


Thermoelectric Performance Of Single-Phase Tellurium-Reduced Quaternary (Pbte)0.55(Pbs)0.1(Pbse)0.35, Laaya Shaabani, Graeme Blake, Andrew Manettas, Shokat Keshavarzi, Sima Aminorroaya-Yamini Jan 2019

Thermoelectric Performance Of Single-Phase Tellurium-Reduced Quaternary (Pbte)0.55(Pbs)0.1(Pbse)0.35, Laaya Shaabani, Graeme Blake, Andrew Manettas, Shokat Keshavarzi, Sima Aminorroaya-Yamini

Australian Institute for Innovative Materials - Papers

Lead chalcogenide quaternary systems have been shown to provide high thermoelectric (TE) efficiency superior to those of binary andternary lead chalcogenides, arising from both altered electronic band structures and a reduction in lattice thermal conductivity. Here, we have synthesized single-phase samples of the quaternary compound (PbTe)0.55(PbS)0.1(PbSe)0.35 dopedwith Na and characterized their TE properties. We show that the dopant solubility is limited to 1 at. %. A very low lattice thermal conductivity of∼0.6 Wm−1K−1at 850 K is achieved at all dopant concentrations because of phonon scattering from point defects associated with solute atoms with high contrastatomic mass. As a result, a …


Flow Analysis Through Collector Well Laterals: A Case Study From Sonoma County Water Agency, California, Matteo D'Alessio, John Lucio, Ernest Williams, James Warner, Donald Seymour, Jay Jasperse, Chittaranjan Ray Jan 2018

Flow Analysis Through Collector Well Laterals: A Case Study From Sonoma County Water Agency, California, Matteo D'Alessio, John Lucio, Ernest Williams, James Warner, Donald Seymour, Jay Jasperse, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

The Sonoma County Water Agency (SWCA) uses six radial collector wells along the Russian River west of Santa Rosa, to provide water for several municipalities and water districts in north-western California. Three collector wells (1, 2, and 6) are located in the Wohler area, and three collector wells (3, 4, and 5) are located in the Mirabel area. The objective of this paper is to highlight the performance of the three collector wells located in the Mirabel area since their construction. The 2015 investigation showed a lower performance of Collectors 3 and 4 compared to their original performances after construction …


Plasma-Induced Amorphous Shell And Deep Cation-Site S Doping Endow Tio2 With Extraordinary Sodium Storage Performance, Hanna He, Dan Huang, Wei Kong Pang, Dan Sun, Qi Wang, Yougen Tang, Xiaobo Ji, Zaiping Guo, Haiyan Wang Jan 2018

Plasma-Induced Amorphous Shell And Deep Cation-Site S Doping Endow Tio2 With Extraordinary Sodium Storage Performance, Hanna He, Dan Huang, Wei Kong Pang, Dan Sun, Qi Wang, Yougen Tang, Xiaobo Ji, Zaiping Guo, Haiyan Wang

Australian Institute for Innovative Materials - Papers

Structural design and modification are effective approaches to regulate the physicochemical properties of TiO 2 , which play an important role in achieving advanced materials. Herein, a plasma-assisted method is reported to synthesize a surface-defect-rich and deep-cation-site-rich S doped rutile TiO 2 (R-TiO 2- x -S) as an advanced anode for the Na ion battery. An amorphous shell (≈3 nm) is induced by the Ar/H 2 plasma, which brings about the subsequent high S doping concentration (≈4.68 at%) and deep doping depth. Experimental results and density functional theory calculations demonstrate greatly facilitated ion diffusion, improved electronic conductivity, and an increased …


Effect Of Alf3-Coated Li4ti5o12 On The Performance And Function Of The Lini0.5mn1.5o4||Li4ti5o12 Full Battery-An In-Operando Neutron Powder Diffraction Study, Gemeng Liang, Anoop Somanathan Pillai Sushamakumari Amma, Vanessa K. Peterson, Kuan-Yu Ko, Chia-Ming Chang, Cheng-Zhang Lu, Chia-Erh Liu, Shih-Chieh Liao, Jin-Ming Chen, Zaiping Guo, Wei Kong Pang Jan 2018

Effect Of Alf3-Coated Li4ti5o12 On The Performance And Function Of The Lini0.5mn1.5o4||Li4ti5o12 Full Battery-An In-Operando Neutron Powder Diffraction Study, Gemeng Liang, Anoop Somanathan Pillai Sushamakumari Amma, Vanessa K. Peterson, Kuan-Yu Ko, Chia-Ming Chang, Cheng-Zhang Lu, Chia-Erh Liu, Shih-Chieh Liao, Jin-Ming Chen, Zaiping Guo, Wei Kong Pang

Australian Institute for Innovative Materials - Papers

The LiNi0.5Mn1.5O4||Li4Ti5O12(LMNO||LTO) battery possesses a relatively-high energy density and cycle performance, with further enhancement possible by application of an AlF3coating on the LTO electrode particles. We measure the performance enhancement to the LMNO||LTO battery achieved by a AlF3coating on the LTO particles through electrochemical testing and use in-operando neutron powder diffraction to study the changes to the evolution of the bulk crystal structure during battery cycling. We find that the AlF3coating along with parasitic Al doping slightly increases capacity and greatly increases rate capability of the LTO electrode, as well as significantly reducing capacity loss on cycling, facilitating a gradual …


Porous Nati2(Po4)(3) Nanocubes Anchored On Porous Carbon Nanosheets For High Performance Sodium-Ion Batteries, Ziqi Wang, Jiaojiao Liang, Kai Fan, Xiaodi Liu, Caiyun Wang, Jianmin Ma Jan 2018

Porous Nati2(Po4)(3) Nanocubes Anchored On Porous Carbon Nanosheets For High Performance Sodium-Ion Batteries, Ziqi Wang, Jiaojiao Liang, Kai Fan, Xiaodi Liu, Caiyun Wang, Jianmin Ma

Australian Institute for Innovative Materials - Papers

NaTi2(PO4)3 has attracted great interest as anode material for sodium ion batteries owing to its open three-dimensional framework structure and limited volume changes during the charge and discharge process. However, the poor intrinsic electronic conductivity of NaTi2(PO4)3 needs to be improved for high rate capability. In this work, porous NaTi2(PO4)3 nanocubes anchored on porous carbon nanosheets (NaTi2(PO4)3/C) are designed and developed. This material exhibits a large discharge capacity and good rate capacity including a first discharge capacity of 485 mAh g−1 at a current density of 0.1 A g−1, and 98 mAh g−1 retained at a high rate of 4 …


Investigation On The Catalytic Performance Of Reduced‐Graphene‐Oxide‐Interpolated Fes2 And Fes For Oxygen Reduction Reaction, Hengyi Fang, Taizhong Huang, Jianfeng Mao, Shuo Yao, M Dinesh, Yue Sun, Dong Liang, Lei Qi, Jiemei Yu, Zhankun Jiang Jan 2018

Investigation On The Catalytic Performance Of Reduced‐Graphene‐Oxide‐Interpolated Fes2 And Fes For Oxygen Reduction Reaction, Hengyi Fang, Taizhong Huang, Jianfeng Mao, Shuo Yao, M Dinesh, Yue Sun, Dong Liang, Lei Qi, Jiemei Yu, Zhankun Jiang

Australian Institute for Innovative Materials - Papers

The oxygen reduction reaction (ORR) plays a key role in many kinds of energy conversion and energy storage devices, especially in fuel cells. Developing low-cost, easily prepared, and high-efficiency catalysts is a crucial factor for the large-scale applications of fuel cells. Herein, we report the reduced graphene oxide (rGO) interpolated FeS2and FeS as low cost and high performance electrocatalyst for ORR in the alkaline electrolyte. Cyclic voltammetry tests indicate that the onset potential of the ORR for FeS2@rGO is −0.142 V, which is close to the state-of-the-art commercial Pt/C (-0.114 V) catalyst. A low Tafel slope of ∼ 98 mV/decade …


Structure-Property Relationships Of Organic Electrolytes And Their Effects On Li/S Battery Performance, Mohammad Kaiser, Shulei Chou, Hua-Kun Liu, Shi Xue Dou, Chunsheng Wang, Jiazhao Wang Jan 2017

Structure-Property Relationships Of Organic Electrolytes And Their Effects On Li/S Battery Performance, Mohammad Kaiser, Shulei Chou, Hua-Kun Liu, Shi Xue Dou, Chunsheng Wang, Jiazhao Wang

Australian Institute for Innovative Materials - Papers

Electrolytes, which are a key component in electrochemical devices, transport ions between the sulfur/carbon composite cathode and the lithium anode in lithium-sulfur batteries (LSBs). The performance of a LSB mostly depends on the electrolyte due to the dissolution of polysulfides into the electrolyte, along with the formation of a solid-electrolyte interphase. The selection of the electrolyte and its functionality during charging and discharging is intricate and involves multiple reactions and processes. The selection of the proper electrolyte, including solvents and salts, for LSBs strongly depends on its physical and chemical properties, which is heavily controlled by its molecular structure. In …


Ag-Mg Antisite Defect Induced High Thermoelectric Performance Of Α-Mgagsb, Zhenzhen Feng, Jihua Zhang, Yuli Yan, Guangbiao Zhang, Chao Wang, Chengxiao Peng, Fengzhu Ren, Yuan Xu Wang, Zhenxiang Cheng Jan 2017

Ag-Mg Antisite Defect Induced High Thermoelectric Performance Of Α-Mgagsb, Zhenzhen Feng, Jihua Zhang, Yuli Yan, Guangbiao Zhang, Chao Wang, Chengxiao Peng, Fengzhu Ren, Yuan Xu Wang, Zhenxiang Cheng

Australian Institute for Innovative Materials - Papers

Engineering atomic-scale native point defects has become an attractive strategy to improve the performance of thermoelectric materials. Here, we theoretically predict that Ag-Mg antisite defects as shallow acceptors can be more stable than other intrinsic defects under Mg-poor-Ag/Sb-rich conditions. Under more Mg-rich conditions, Ag vacancy dominates the intrinsic defects. The p-type conduction behavior of experimentally synthesized ¿-MgAgSb mainly comes from Ag vacancies and Ag antisites (Ag on Mg sites), which act as shallow acceptors. Ag-Mg antisite defects significantly increase the thermoelectric performance of ¿-MgAgSb by increasing the number of band valleys near the Fermi level. For Li-doped ¿-MgAgSb, under more …


Ultra-Light And Flexible Pencil-Trace Anode For High Performance Potassium-Ion And Lithium-Ion Batteries, Zhixin Tai, Yajie Liu, Qing Zhang, Tengfei Zhou, Zaiping Guo, Hua-Kun Liu, Shi Xue Dou Jan 2017

Ultra-Light And Flexible Pencil-Trace Anode For High Performance Potassium-Ion And Lithium-Ion Batteries, Zhixin Tai, Yajie Liu, Qing Zhang, Tengfei Zhou, Zaiping Guo, Hua-Kun Liu, Shi Xue Dou

Australian Institute for Innovative Materials - Papers

Engineering design of battery configurations and new battery system development are alternative approaches to achieve high performance batteries. A novel flexible and ultra-light graphite anode is fabricated by simple friction drawing on filter paper with a commercial 8B pencil. Compared with the traditional anode using copper foil as current collector, this innovative current-collector-free design presents capacity improvement of over 200% by reducing the inert weight of the electrode. The as-prepared pencil-trace electrode exhibits excellent rate performance in potassium-ion batteries (KIBs), significantly better than in lithium-ion batteries (LIBs), with capacity retention of 66% for the KIB vs. 28% for the LIB …


Capillary-Induced Ge Uniformly Distributed In N-Doped Carbon Nanotubes With Enhanced Li-Storage Performance, Haipeng Guo, Boyang Ruan, Lili Liu, Lei Zhang, Zhanliang Tao, Shulei Chou, Jiazhao Wang, Hua-Kun Liu Jan 2017

Capillary-Induced Ge Uniformly Distributed In N-Doped Carbon Nanotubes With Enhanced Li-Storage Performance, Haipeng Guo, Boyang Ruan, Lili Liu, Lei Zhang, Zhanliang Tao, Shulei Chou, Jiazhao Wang, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Germanium (Ge) is a prospective anode material for lithium-ion batteries, as it possesses large theoretical capacity, outstanding lithium-ion diffusivity, and excellent electrical conductivity. Ge suffers from drastic capacity decay and poor rate performance, however, owing to its low electrical conductivity and huge volume expansion during cycling processes. Herein, a novel strategy has been developed to synthesize a Ge at N-doped carbon nanotubes (Ge at N-CNTs) composite with Ge nanoparticles uniformly distributed in the N-CNTs by using capillary action. This unique structure could effectively buffer large volume expansion. When evaluated as an anode material, the Ge at N-CNTs demonstrate enhanced cycling …


Expeditious And Eco-Friendly Hydrothermal Polymerization Of Pedot Nanoparticles For Binderfree High Performance Supercapacitor Electrodes, Murugesan Rajesh, C Justin Raj, Byung Chul Kim, Ramu Manikandan, Sung Jin Kim, Sang-Yeup Prof Sang-Yeup Park, Kwangsoo Lee, Kook Hyun Yu Jan 2016

Expeditious And Eco-Friendly Hydrothermal Polymerization Of Pedot Nanoparticles For Binderfree High Performance Supercapacitor Electrodes, Murugesan Rajesh, C Justin Raj, Byung Chul Kim, Ramu Manikandan, Sung Jin Kim, Sang-Yeup Prof Sang-Yeup Park, Kwangsoo Lee, Kook Hyun Yu

Australian Institute for Innovative Materials - Papers

Poly(3,4-ethylenedioxythiophene) (PEDOT) is a promising conjugated polymer that has attracted attention because of its outstanding electronic properties, useful for a wide range of applications in energy storage devices. However, synthesis of high-quality PEDOT occurs via vapour phase polymerization and chemical vapour deposition techniques using extrinsic hard templates or complicated experimental setups. This study introduces a simple hydrothermal polymerization technique using ferric chloride (FeCl3) as an oxidizing agent to overcome the above drawback, which results in good conductive, crystalline PEDOT nanodendrites and nanospheres. The effects of varying the molar ratio of FeCl3 oxidant were investigated in terms of the structural, morphological …


Significant Enhancement Of The Cycling Performance And Rate Capability Of The P/C Composite Via Chemical Bonding (P-C), Weijie Li, Shulei Chou, Jiazhao Wang, Hua-Kun Liu, S X. Dou Jan 2016

Significant Enhancement Of The Cycling Performance And Rate Capability Of The P/C Composite Via Chemical Bonding (P-C), Weijie Li, Shulei Chou, Jiazhao Wang, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

Among anode materials for sodium ion batteries, red phosphorus is a very promising one due to its abundant reserves, low-cost and high theoretical capacity of 2600 mA h g-1. However, its huge volume expansion on sodiation (∼490%) and poor conductivity leads to dramatic capacity decay, restraining its practical application. To improve the electrochemical performance, here, we prepared a red phosphorus and graphene nanoplate composite using cheap red P and natural graphite as the starting materials via a simple and scalable ball-milling method. The phosphorus-carbon bond formed during the milling process improves the electrical connectivity between P particles and graphene nanoplates, …


A High-Performance Rechargeable Mg2+/Li+ Hybrid Battery Using One-Dimensional Mesoporous Tio2(B) Nanoflakes As The Cathode, Shuojian Su, Yanna Nuli, Zhenguo Huang, Qi Miao, Jun Yang, Jiulin Wang Jan 2016

A High-Performance Rechargeable Mg2+/Li+ Hybrid Battery Using One-Dimensional Mesoporous Tio2(B) Nanoflakes As The Cathode, Shuojian Su, Yanna Nuli, Zhenguo Huang, Qi Miao, Jun Yang, Jiulin Wang

Australian Institute for Innovative Materials - Papers

Mg2+/Li+ hybrid batteries have recently been constructed combining a Mg anode, a Li+-intercalation electrode, and an electrolyte containing both Mg2+ and Li+. These batteries have been reported to outperform all the previously reported magnesium batteries in terms of specific capacity, cycling stability, and rate capability. Herein, we report the outstanding electrochemical performance of Mg2+/Li+ hybrid batteries consisting of a one-dimensional mesoporous TiO2(B) cathode, a Mg anode, and an electrolyte consisting of 0.5 mol L-1 Mg(BH4)2 + 1.5 mol L-1 LiBH4 in tetraglyme. A highly synergetic interaction between Li+ and Mg2+ ions toward the pseudo-capacitive reaction is proposed. The hybrid batteries …


Superior Sodium-Ion Storage Performance Of Co3o4@Nitrogen-Doped Carbon: Derived From A Metal–Organic Framework, Ying Wang, Caiyun Wang, Yijing Wang, Hua-Kun Liu, Zhenguo Huang Jan 2016

Superior Sodium-Ion Storage Performance Of Co3o4@Nitrogen-Doped Carbon: Derived From A Metal–Organic Framework, Ying Wang, Caiyun Wang, Yijing Wang, Hua-Kun Liu, Zhenguo Huang

Australian Institute for Innovative Materials - Papers

Nitrogen-doped carbon coated Co 3 O 4 nanoparticles (Co 3 O 4 @NC) with high Na-ion storage capacity and unprecedented long-life cycling stability are reported in this paper. The Co 3 O 4 @NC was derived from a metal – organic framework ZIF-67, where the Co ions and organic linkers were, respectively, converted to Co 3 O 4 nanoparticle cores and nitrogen-doped carbon shells through a controlled two-step annealing process. The Co 3 O 4 @NC shows a porous nature with a surface area of 101 m 2 g 1 . When applied as an anode for sodium ion batteries …


Lead-Free Snte-Based Thermoelectrics: Enhancement Of Thermoelectric Performance By Doping With Gd/Ag, Lijuan Zhang, Jian Li Wang, Zhenxiang Cheng, Qiao Sun, Zhen Li, S X. Dou Jan 2016

Lead-Free Snte-Based Thermoelectrics: Enhancement Of Thermoelectric Performance By Doping With Gd/Ag, Lijuan Zhang, Jian Li Wang, Zhenxiang Cheng, Qiao Sun, Zhen Li, S X. Dou

Australian Institute for Innovative Materials - Papers

SnTe, with the same rock-salt structure as PbTe, is a potentially attractive thermoelectric material. Pristine SnTe has poor thermoelectric performance because of its very high hole concentration resulting from intrinsic Sn vacancies, which leads to a high thermal conductivity and a low Seebeck coefficient. In this work, the thermoelectric properties of SnTe were modified by doping with different contents of gadolinium and silver. It is found that SnTe doped with optimal gadolinium (i.e. Gd0.06Sn0.94Te) exhibited extraordinarily low lattice thermal conductivity that is close to the theoretical minimum. The drastic reduction of lattice thermal conductivity is attributed to the formation of …


Light Activated Electrochemistry: Light Intensity And Ph Dependence On Electrochemical Performance Of Anthraquinone Derivatized Silicon, Ying Yang, Simone Ciampi, Moinul H. Choudhury, J Justin Gooding Jan 2016

Light Activated Electrochemistry: Light Intensity And Ph Dependence On Electrochemical Performance Of Anthraquinone Derivatized Silicon, Ying Yang, Simone Ciampi, Moinul H. Choudhury, J Justin Gooding

Australian Institute for Innovative Materials - Papers

We seek to understand how the thermodynamics and kinetics of anthraquinone-containing self-assembled monolayer on silicon electrodes are affected by two key experimental variables: the intensity of the light assisting the anthraquinone/anthrahydroquinone redox process and the local solution environment. The substrates are chemically passivated poorly doped p-type silicon electrodes. The study presents a strategy for the selective modulation of either the anodic or the cathodic process occurring at the interface. Cyclic voltammetry studies showed that unlike for a proton-coupled electron transfer process performed at metallic electrodes, for the redox reaction of the anthraquinone unit on a silicon electrode it becomes possible …


Characteristics And Cadmium Extraction Performance Of Pvc/Aliquat 336 Electrospun Fibres In Comparison With Polymer Inclusion Membranes, Nurul Syazana Binti Abdul Halim, Philip G. Whitten, Long D. Nghiem Jan 2016

Characteristics And Cadmium Extraction Performance Of Pvc/Aliquat 336 Electrospun Fibres In Comparison With Polymer Inclusion Membranes, Nurul Syazana Binti Abdul Halim, Philip G. Whitten, Long D. Nghiem

Australian Institute for Innovative Materials - Papers

Electrospun fibres and polymer inclusion membranes (PIMs) were prepared from polyvinyl chloride (PVC) and Aliquat 336. Morphological and thermomechanical properties of the electrospun mats differed notably from those of PIMs. The plasticizing effect of Aliquat 336 on electrospun PVC/Aliquat 336 fibres was confirmed by the shifting of the glass transition temperature (Tg). By contrast, Aliquat 336 did not act as a plasticizer in PIMs as Tg was independent of Aliquat 336 concentration. Cadmium extraction to electrospun fibres could occur at a lower Aliquat 336 content (i.e. 6 wt.%) compared with PIMs. At 40 wt.% Aliquat 336 content, both PIMs and …


Effect Of Tensile Load On The Actuation Performance Of Ph-Sensitive Hydrogels, Sina Naficy, Geoffrey M. Spinks Jan 2015

Effect Of Tensile Load On The Actuation Performance Of Ph-Sensitive Hydrogels, Sina Naficy, Geoffrey M. Spinks

Australian Institute for Innovative Materials - Papers

pH-responsive hydrogels are capable of converting chemical energy to mechanical work. To optimize their use as actuators, their response when operating against an external load must be fully characterized. Here, the actuation strain of a model pH-sensitive hydrogel as a function of different constant loads is studied. The experimental actuation strain, produced by switching the pH from 2 to 12, decreases significantly and monotonically with increasing initial tensile load. Two models are developed to predict the actuation strain as a function of applied stress. Simple mechanical models based on the change in hydrogel modulus and cross sectional area due to …


Effective Enhancement Of The Electrochemical Performance Of Layered Cathode Li1.5mn0.75ni0.25o2.5 Via A Novel Facile Molten Salt Method, Zhuo Zheng, Wei-Bo Hua, S Liao, Yan Jun Zhong, En-Hui Wang, Bin-Bin Xu, Hua-Kun Liu, Ben-He Zhong Jan 2015

Effective Enhancement Of The Electrochemical Performance Of Layered Cathode Li1.5mn0.75ni0.25o2.5 Via A Novel Facile Molten Salt Method, Zhuo Zheng, Wei-Bo Hua, S Liao, Yan Jun Zhong, En-Hui Wang, Bin-Bin Xu, Hua-Kun Liu, Ben-He Zhong

Australian Institute for Innovative Materials - Papers

A series of nanocrystalline lithium-rich cathode materials Li1.5Mn0.75Ni0.25O2.5 have been prepared by a novel synthetic process, which combines the co-precipitation method and a modified molten salt method. By using a moderate excess of 0.5LiNO3-0.5LiOH eutectic salts as molten media and reactants, the usage of deionized water or alcohol in the subsequent wash process is successfully reduced, compared with the traditional molten salt method. The materials with different excess Li salt content, Li/M (M = Ni + Mn) = 1.55, 1.65, 1.75, 1.85, 1.95, 2.05, molar ratio, show distinct differences in their …


Synthesis Of Nitrogen-Doped Graphene Via Thermal Treatment Of Graphene Oxide Within Methylimidazole And Its Capacitance Performance As Electric Double Layer Capacitor, Md. Monirul Islam, Shaikh Nayeem Faisal, Anup Kumar Roy, Sonia Ansari, Dean Cardillo, Konstantin K. Konstantinov, Enamul Haque Jan 2015

Synthesis Of Nitrogen-Doped Graphene Via Thermal Treatment Of Graphene Oxide Within Methylimidazole And Its Capacitance Performance As Electric Double Layer Capacitor, Md. Monirul Islam, Shaikh Nayeem Faisal, Anup Kumar Roy, Sonia Ansari, Dean Cardillo, Konstantin K. Konstantinov, Enamul Haque

Australian Institute for Innovative Materials - Papers

Nitrogen-doped graphene was successfully synthesised from graphene oxide (GO) and 2-methylimidazole composite via thermal treatment under argon flow at 700oC within 1h. This synthesised N-doped graphene exhibits homogeneous nitrogen doping with concentration of ~5% in three different nitrogen configuration namelypyridinic N, pyrrolic N and graphitic N. The electric double layer capacitor (EDLC) made up with this N-doped graphene showed excellent specific capacitance 274 F/g at current density of 1A/g, which was ~7 times higher than GO. This EDLC capacitor showed excellent cyclic stability up to 5000 cycles with capacity retention of ~91%.


3d Hierarchical Porous Graphene Aerogel With Tunable Meso-Pores On Graphene Nanosheets For High-Performance Energy Storage, Long Ren, K N. Hui, K S. Hui, Yundan Liu, Xiang Qi, Jianxin Zhong, Yi Du, Jianping Yang Jan 2015

3d Hierarchical Porous Graphene Aerogel With Tunable Meso-Pores On Graphene Nanosheets For High-Performance Energy Storage, Long Ren, K N. Hui, K S. Hui, Yundan Liu, Xiang Qi, Jianxin Zhong, Yi Du, Jianping Yang

Australian Institute for Innovative Materials - Papers

New and novel 3D hierarchical porous graphene aerogels (HPGA) with uniform and tunable mesopores (e.g., 21 and 53 nm) on graphene nanosheets (GNS) were prepared by a hydrothermal self-assembly process and an in-situ carbothermal reaction. The size and distribution of the meso-pores on the individual GNS were uniform and could be tuned by controlling the sizes of the Co3O4 NPs used in the hydrothermal reaction. This unique architecture of HPGA prevents the stacking of GNS and promises more electrochemically active sites that enhance the electrochemical storage level significantly. HPGA, as a lithium-ion battery anode, exhibited superior electrochemical performance, including a …


Dual Yolk-Shell Structure Of Carbon And Silica-Coated Silicon For High-Performance Lithium-Ion Batteries, L Y. Yang, H Z. Li, Jun Liu, Ziqi Sun, S S. Tang, M Lei Jan 2015

Dual Yolk-Shell Structure Of Carbon And Silica-Coated Silicon For High-Performance Lithium-Ion Batteries, L Y. Yang, H Z. Li, Jun Liu, Ziqi Sun, S S. Tang, M Lei

Australian Institute for Innovative Materials - Papers

Silicon batteries have attracted much attention in recent years due to their high theoretical capacity, although a rapid capacity fade is normally observed, attributed mainly to volume expansion during lithiation. Here, we report for the first time successful synthesis of Si/void/SiO2/void/C nanostructures. The synthesis strategy only involves selective etching of SiO2 in Si/SiO2/C structures with hydrofluoric acid solution. Compared with reported results, such novel structures include a hard SiO2-coated layer, a conductive carbon-coated layer, and two internal void spaces. In the structures, the carbon can enhance conductivity, the SiO2 layer has mechanically …