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- Australian Institute for Innovative Materials - Papers (32)
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Articles 1 - 30 of 43
Full-Text Articles in Engineering
Enhancing The Visibility Of Vernier Effect In A Tri-Microfiber Coupler Fiber Loop Interferometer For Ultrasensitive Refractive Index And Temperature Sensing, Fangfang Wei, Dejun Liu, Zhe Wang, Zhuochen Wang, Gerald Farrell, Qiang Wu, Gang-Ding Peng, Yuliya Semenova
Enhancing The Visibility Of Vernier Effect In A Tri-Microfiber Coupler Fiber Loop Interferometer For Ultrasensitive Refractive Index And Temperature Sensing, Fangfang Wei, Dejun Liu, Zhe Wang, Zhuochen Wang, Gerald Farrell, Qiang Wu, Gang-Ding Peng, Yuliya Semenova
Articles
In this paper a Vernier effect based sensor is analyzed and demonstrated experimentally in a tri-microfiber coupler (Tri-MFC) and polarization-maintaining fiber (PMF) loop interferometer (Tri-MFC-PMF) to provide ultrasensitive refractive index and temperature sensing. The main novelty of this work is an analysis of parameters of the proposed Tri-MFC-PMF with the objective of determining the conditions leading to a strong Vernier effect. It has been identified by simulation that the Vernier effect is a primary factor in the design of Tri-MFC-PMF loop sensing structure for sensitivity enhancement. It is furthermore demonstrated experimentally that enhancing the visibility of the Vernier spectrum in …
University Of Kentucky Measurements Of Wind, Temperature, Pressure And Humidity In Support Of Lapse-Rate Using Multisite Fixed-Wing And Rotorcraft Unmanned Aerial Systems, Sean C. C. Bailey, Michael P. Sama, Caleb A. Canter, Luis Felipe Pampolini, Zachary S. Lippay, Travis J. Schuyler, Jonathan D. Hamilton, Sean B. Macphee, Isaac S. Rowe, Christopher D. Sanders, Virginia G. Smith, Christina N. Vezzi, Harrison M. Wight, Jesse B. Hoagg, Marcelo I. Guzman, Suzanne Weaver Smith
University Of Kentucky Measurements Of Wind, Temperature, Pressure And Humidity In Support Of Lapse-Rate Using Multisite Fixed-Wing And Rotorcraft Unmanned Aerial Systems, Sean C. C. Bailey, Michael P. Sama, Caleb A. Canter, Luis Felipe Pampolini, Zachary S. Lippay, Travis J. Schuyler, Jonathan D. Hamilton, Sean B. Macphee, Isaac S. Rowe, Christopher D. Sanders, Virginia G. Smith, Christina N. Vezzi, Harrison M. Wight, Jesse B. Hoagg, Marcelo I. Guzman, Suzanne Weaver Smith
Mechanical Engineering Faculty Publications
In July 2018, unmanned aerial systems (UASs) were deployed to measure the properties of the lower atmosphere within the San Luis Valley, an elevated valley in Colorado, USA, as part of the Lower Atmospheric Profiling Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (LAPSE-RATE). Measurement objectives included detailing boundary layer transition, canyon cold-air drainage and convection initiation within the valley. Details of the contribution to LAPSE-RATE made by the University of Kentucky are provided here, which include measurements by seven different fixed-wing and rotorcraft UASs totaling over 178 flights with validated data. The data from these coordinated UAS flights …
Using A Balloon-Launched Unmanned Glider To Validate Real-Time Wrf Modeling, Travis J. Schuyler, S. M. Iman Gohari, Gary Pundsack, Donald Berchoff, Marcelo I. Guzman
Using A Balloon-Launched Unmanned Glider To Validate Real-Time Wrf Modeling, Travis J. Schuyler, S. M. Iman Gohari, Gary Pundsack, Donald Berchoff, Marcelo I. Guzman
Chemistry Faculty Publications
The use of small unmanned aerial systems (sUAS) for meteorological measurements has expanded significantly in recent years. SUAS are efficient platforms for collecting data with high resolution in both space and time, providing opportunities for enhanced atmospheric sampling. Furthermore, advances in mesoscale weather research and forecasting (WRF) modeling and graphical processing unit (GPU) computing have enabled high resolution weather modeling. In this manuscript, a balloon-launched unmanned glider, complete with a suite of sensors to measure atmospheric temperature, pressure, and relative humidity, is deployed for validation of real-time weather models. This work demonstrates the usefulness of sUAS for validating and improving …
Flying By Fire: Making Controlled Burns Safer For Humans And Uavs, Rebecca Horzewski, Carrick Detweiler
Flying By Fire: Making Controlled Burns Safer For Humans And Uavs, Rebecca Horzewski, Carrick Detweiler
UCARE Research Products
A temperature sensing circuit board was developed that will allow Nimbus Lab's controlled burn starting UAV to react to the temperatures around it.
Improved Superconducting Properties In The Mg11b2 Low Activation Superconductor Prepared By Low-Temperature Sintering, Fang Cheng, Yongchang Liu, Zongqing Ma, M Shahriar Al Hossain, Mehmet Somer
Improved Superconducting Properties In The Mg11b2 Low Activation Superconductor Prepared By Low-Temperature Sintering, Fang Cheng, Yongchang Liu, Zongqing Ma, M Shahriar Al Hossain, Mehmet Somer
Australian Institute for Innovative Materials - Papers
Mg11B2 has a great application prospect in the superconducting coils for fusion reactor as the "low activation superconductors". The un-doped Mg11B2 and Cu-doped Mg11B2 bulks using 11B as a boron precursor were fabricated by low-temperature sintering in present work. It was found that the prepared Mg11B2 low activation superconductors exhibit better Jc performance than all of other Mg11B2 samples reported in previous studies. As for Cu doped Mg11B2, minor Cu addition can obviously improve the Mg11B2 grain crystallization and reduce the amount of MgO impurity. Hence, improved grain connectivity and higher Jc at low fields is obtained in Cu doped …
Contribution Of Radicals And Ions In Catalyzed Growth Of Single-Walled Carbon Nanotubes From Low-Temperature Plasmas, Z Marvi, S Xu, G Foroutan, Kostya Ostrikov
Contribution Of Radicals And Ions In Catalyzed Growth Of Single-Walled Carbon Nanotubes From Low-Temperature Plasmas, Z Marvi, S Xu, G Foroutan, Kostya Ostrikov
Australian Institute for Innovative Materials - Papers
The growth kinetics of single-walled carbon nanotubes (SWCNTs) in a low-temperature, low-pressure reactive plasma is investigated using a multiscale numerical simulation, including the plasma sheath and surface diffusion modules. The plasma-related effects on the characteristics of SWCNT growth are studied. It is found that in the presence of reactive radicals in addition to energetic ions inside the plasma sheath area, the effective carbon flux, and the growth rate of SWCNT increase. It is shown that the concentration of atomic hydrogen and hydrocarbon radicals in the plasma plays an important role in the SWCNT growth. The effect of the effective carbon …
Superior Critical Current Density Obtained In Mg11b2 Low Activation Superconductor By Using Reactive Amorphous 11b And Optimizing Sintering Temperature, Fang Cheng, Yongchang Liu, Zongqing Ma, Huijun Li, Md Shahriar Hossain
Superior Critical Current Density Obtained In Mg11b2 Low Activation Superconductor By Using Reactive Amorphous 11b And Optimizing Sintering Temperature, Fang Cheng, Yongchang Liu, Zongqing Ma, Huijun Li, Md Shahriar Hossain
Australian Institute for Innovative Materials - Papers
The un-doped Mg11B2 and Cu-doped Mg11B2 bulks using 11B as a boron precursor were fabricated by solid-state reaction and sintered at different temperature in present work. By analyzing the sintering process, it was found that 11B original powder is more reactive and can react with Mg severely even at low temperature before Mg melting, which leads to the formation of refined Mg11B2 grains. Consequently, the critical current density of Mg11B2 sample prepared in this work is higher than that of natural MgB2. Furthermore, it was found that proper Cu addition …
Significantly Enhanced Critical Current Density In Nano-Mgb2 Grains Rapidly Formed At Low Temperature With Homogeneous Carbon Doping, Yongchang Liu, Feng Lan, Zongqing Ma, Ning Chen, Huijun Li, Shaon Barua, Dipakkumar Patel, Md S. Hossain, S Acar, Jung Ho Kim, S X. Dou
Significantly Enhanced Critical Current Density In Nano-Mgb2 Grains Rapidly Formed At Low Temperature With Homogeneous Carbon Doping, Yongchang Liu, Feng Lan, Zongqing Ma, Ning Chen, Huijun Li, Shaon Barua, Dipakkumar Patel, Md S. Hossain, S Acar, Jung Ho Kim, S X. Dou
Australian Institute for Innovative Materials - Papers
High performance MgB2 bulks using carbon-coated amorphous boron as a boron precursor were fabricated by Cu-activated sintering at low temperature (600 °C, below the Mg melting point). Dense nano-MgB2 grains with a high level of homogeneous carbon doping were formed in these MgB2 samples. This type of microstructure can provide a stronger flux pinning force, together with depressed volatility and oxidation of Mg owing to the low-temperature Cu-activated sintering, leading to a significant improvement of critical current density (Jc) in the as-prepared samples. In particular, the value of Jc for the carbon-coated (Mg …
Harvesting Temperature Fluctuations As Electrical Energy Using Torsional And Tensile Polymer Muscles, Shi Hyeong Kim, Marcio Dias Lima, Mikhail E. Kozlov, Carter S. Haines, Geoffrey M. Spinks, Shazed Aziz, Changsoon Choi, Hyeon Jun Sim, Xuemin Wang, Hongbing Lu, Dong Qian, John D. W Madden, Ray H. Baughman, Seon Jeong Kim
Harvesting Temperature Fluctuations As Electrical Energy Using Torsional And Tensile Polymer Muscles, Shi Hyeong Kim, Marcio Dias Lima, Mikhail E. Kozlov, Carter S. Haines, Geoffrey M. Spinks, Shazed Aziz, Changsoon Choi, Hyeon Jun Sim, Xuemin Wang, Hongbing Lu, Dong Qian, John D. W Madden, Ray H. Baughman, Seon Jeong Kim
Australian Institute for Innovative Materials - Papers
Diverse means have been deployed for harvesting electrical energy from mechanical actuation produced by low-grade waste heat, but cycle rate, energy-per-cycle, device size and weight, or cost have limited applications. We report the electromagnetic harvesting of thermal energy as electrical energy using thermally powered torsional and tensile artificial muscles made from inexpensive polymer fibers used for fishing line and sewing thread. We show that a coiled 27 μm-diameter nylon muscle fiber can be driven by 16.7 °C air temperature fluctuations to spin a magnetic rotor to a peak torsional rotation speed of 70 000 rpm for over 300 000 heating-cooling …
Harvesting Temperature Fluctuations As Electrical Energy Using Torsional And Tensile Polymer Muscles, Shi Hyeong Kim, Marcio Dias Lima, Mikhail E. Kozlov, Carter S. Haines, Geoffrey M. Spinks, Shazed Aziz, Changsoon Choi, Hyeon Jun Sim, Xuemin Wang, Hongbing Lu, Dong Qian, John D. W Madden, Ray H. Baughman, Seon Jeong Kim
Harvesting Temperature Fluctuations As Electrical Energy Using Torsional And Tensile Polymer Muscles, Shi Hyeong Kim, Marcio Dias Lima, Mikhail E. Kozlov, Carter S. Haines, Geoffrey M. Spinks, Shazed Aziz, Changsoon Choi, Hyeon Jun Sim, Xuemin Wang, Hongbing Lu, Dong Qian, John D. W Madden, Ray H. Baughman, Seon Jeong Kim
Australian Institute for Innovative Materials - Papers
Diverse means have been deployed for harvesting electrical energy from mechanical actuation produced by low-grade waste heat, but cycle rate, energy-per-cycle, device size and weight, or cost have limited applications. We report the electromagnetic harvesting of thermal energy as electrical energy using thermally powered torsional and tensile artificial muscles made from inexpensive polymer fibers used for fishing line and sewing thread. We show that a coiled 27 μm-diameter nylon muscle fiber can be driven by 16.7 °C air temperature fluctuations to spin a magnetic rotor to a peak torsional rotation speed of 70 000 rpm for over 300 000 heating-cooling …
Improvement In Structure And Superconductivity Of Bulk Fese0.5te0.5 Superconductors By Optimizing Sintering Temperature, Ning Chen, Yongchang Liu, Zongqing Ma, Liming Yu, Huijun Li
Improvement In Structure And Superconductivity Of Bulk Fese0.5te0.5 Superconductors By Optimizing Sintering Temperature, Ning Chen, Yongchang Liu, Zongqing Ma, Liming Yu, Huijun Li
Australian Institute for Innovative Materials - Papers
Sintering temperature plays a vital role in the evolution of phase structure and microstructure in polycrystalline FeSe0.5Te0.5 bulks fabricated by the two-step sintering method, and thus significantly influences their superconducting properties. Elevated sintering temperature (600-700°C) at second step facilitates the substitution of Te into the superconducting phase, which leads to the increased lattice distortion and thus contributes to the enhancement of superconductivity (the value of Tc reaches 15.6K). At the same time, the accelerated growth of the superconducting grains and the improved homogeneity motivated by elevated sintering temperature serve as the main reason for the sharp superconducting transition.
Conductive Surfaces With Dynamic Switching In Response To Temperature And Salt, Alissa Hackett, Jenny Malmström, Paul J. Molino, Julien Gautrot, Hongrui Zhang, Michael J. Higgins, Gordon G. Wallace, David E. Williams, Jadranka Travas-Sejdic
Conductive Surfaces With Dynamic Switching In Response To Temperature And Salt, Alissa Hackett, Jenny Malmström, Paul J. Molino, Julien Gautrot, Hongrui Zhang, Michael J. Higgins, Gordon G. Wallace, David E. Williams, Jadranka Travas-Sejdic
Australian Institute for Innovative Materials - Papers
This work demonstrates polymer brushes grafted from conductive polymer films which display dynamic surface switching dependent on salt, temperature and electrode potential. The electroactivity presented by the conductive polymer and the responsiveness of the grafted brushes leads to an interface with multiple control parameters. Here, we demonstrate this concept by grafting of uncharged brushes of poly(ethylene glycol)methyl ether methacrylates from conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT), and observe a temperature- and salt-induced switch of brush conformation, and their effect on the electrochemistry of the material. The switching conditions can be tailored by copolymerizing monomers with different numbers of ethylene glycol units. In …
Simulation Study Of Hemt Structures With Hfo2 Cap Layer For Mitigating Inverse Piezoelectric Effect Related Device Failures, Deepthi Nagulapally, Ravi P. Joshi, Aswini Pradhan
Simulation Study Of Hemt Structures With Hfo2 Cap Layer For Mitigating Inverse Piezoelectric Effect Related Device Failures, Deepthi Nagulapally, Ravi P. Joshi, Aswini Pradhan
Electrical & Computer Engineering Faculty Publications
The Inverse Piezoelectric Effect (IPE) is thought to contribute to possible device failure of GaN High Electron Mobility Transistors (HEMTs). Here we focus on a simulation study to probe the possible mitigation of the IPE by reducing the internal electric fields and related elastic energy through the use of high-k materials. Inclusion of a HfO2 "cap layer" above the AlGaN barrier particularly with a partial mesa structure is shown to have potential advantages. Simulations reveal even greater reductions in the internal electric fields by using "field plates" in concert with high-k oxides
Low Cost Infrared And Near Infrared Sensors For Uavs, Samuel T. Aden, James P. Bialas, Zachary Champion, Eugene Levin, Jessica L. Mccarty
Low Cost Infrared And Near Infrared Sensors For Uavs, Samuel T. Aden, James P. Bialas, Zachary Champion, Eugene Levin, Jessica L. Mccarty
Michigan Tech Research Institute Publications
Thermal remote sensing has a wide range of applications, though the extent of its use is inhibited by cost. Robotic and computer components are now widely available to consumers on a scale that makes thermal data a readily accessible resource. In this project, thermal imagery collected via a lightweight remote sensing Unmanned Aerial Vehicle (UAV) was used to create a surface temperature map for the purpose of providing wildland firefighting crews with a cost-effective and time-saving resource. The UAV system proved to be flexible, allowing for customized sensor packages to be designed that could include visible or infrared cameras, GPS, …
Pmn-Pt Based Quaternary Piezoceramics With Enhanced Piezoelectricity And Temperature Stability, Nengneng Luo, Shujun Zhang, Qiang Li, Qingfeng Yan, Wenhui He, Yiling Zhang, Thomas R. Shrout
Pmn-Pt Based Quaternary Piezoceramics With Enhanced Piezoelectricity And Temperature Stability, Nengneng Luo, Shujun Zhang, Qiang Li, Qingfeng Yan, Wenhui He, Yiling Zhang, Thomas R. Shrout
Australian Institute for Innovative Materials - Papers
The phase structure, piezoelectric, dielectric, and ferroelectric properties of (0.80-x)PMN-0.10PFN-0.10PZ-xPT were investigated systematically. The morphotropic phase boundary (MPB) was confirmed to be 0.30
Achieving Single Domain Relaxor-Pt Crystals By High Temperature Poling, Fei Li, Linghang Wang, Li Jin, Zhuo Xu, Shujun Zhang
Achieving Single Domain Relaxor-Pt Crystals By High Temperature Poling, Fei Li, Linghang Wang, Li Jin, Zhuo Xu, Shujun Zhang
Australian Institute for Innovative Materials - Papers
Single domain relaxor-PT crystals are important from both fundamental and application viewpoints. Compared to domain engineered relaxor-PT crystals, however, single domain crystals are prone to cracking during poling. In this paper, based on the analysis of the cracking phenomenon in [001] poled tetragonal 0.25Pb(In0.5Nb0.5)O3-0.37Pb(Mg 1/3Nb2/3)O3-0.38PbTiO3 (PIN-PMN-PT) crystals, the non-180°ferroelastic domain switching was thought to be the dominant factor for cracking during the poling process. A high temperature poling technique, by which the domain switching can be greatly avoided, was proposed to achieve the single domain relaxor-PT crystals. By this poling approach, a quasi-single domain crystal was obtained without cracks. In …
Ultra-High Performance, High-Temperature Superconducting Wires Via Cost-Effective, Scalable, Co-Evaporation Process, Ho-Sup Kim, Sang-Soo Oh, Hong-Soo Ha, Dojun Youm, Seung-Hyun Moon, Jung Ho Kim, S X. Dou, Yoon-Uk Heo, Sung-Hun Wee, Amit Goyal
Ultra-High Performance, High-Temperature Superconducting Wires Via Cost-Effective, Scalable, Co-Evaporation Process, Ho-Sup Kim, Sang-Soo Oh, Hong-Soo Ha, Dojun Youm, Seung-Hyun Moon, Jung Ho Kim, S X. Dou, Yoon-Uk Heo, Sung-Hun Wee, Amit Goyal
Australian Institute for Innovative Materials - Papers
Long-length, high-temperature superconducting (HTS) wires capable of carrying high critical current, Ic, are required for a wide range of applications. Here, we report extremely high performance HTS wires based on 5 μm thick SmBa2Cu3O7 − δ (SmBCO) single layer films on textured metallic templates. SmBCO layer wires over 20 meters long were deposited by a cost-effective, scalable co-evaporation process using a batch-type drum in a dual chamber. All deposition parameters influencing the composition, phase, and texture of the films were optimized via a unique combinatorial method that is broadly applicable for co-evaporation of other promising complex materials containing several cations. …
Enhancement Of Transition Temperature In Fexse0.5te0.5 Film Via Iron Vacancies, J C. Zhuang, Wai K. Yeoh, Xiangyuan Cui, Jung Ho Kim, Dongqi Shi, Z X. Shi, S P. Ringer, Xiaolin Wang, S X. Dou
Enhancement Of Transition Temperature In Fexse0.5te0.5 Film Via Iron Vacancies, J C. Zhuang, Wai K. Yeoh, Xiangyuan Cui, Jung Ho Kim, Dongqi Shi, Z X. Shi, S P. Ringer, Xiaolin Wang, S X. Dou
Australian Institute for Innovative Materials - Papers
The effects of iron deficiency in Fe x Se0.5Te0.5 thin films (0.8 ≤ x ≤ 1) on superconductivity and electronic properties have been studied. A significant enhancement of the superconducting transition temperature (TC ) up to 21 K was observed in the most Fe deficient film (x = 0.8). Based on the observed and simulated structural variation results, there is a high possibility that Fe vacancies can be formed in the Fe x Se0.5Te0.5 films. The enhancement of TC shows a strong relationship with the lattice strain effect induced by Fe vacancies. Importantly, the presence of Fe vacancies alters the …
Influence Of Capping On The Atomistic Arrangement In Palladium Nanoparticles At Room Temperature, Gaston Corthey, Jimena A. Olmos-Asar, Gilberto Casillas, Marcelo M. Mariscal, Sergio Mejia-Rosales, Julio C. Azcarate, Eduardo Larios, Miguel Jose-Yacaman, Roberto Salvarezza, M Fonticelli
Influence Of Capping On The Atomistic Arrangement In Palladium Nanoparticles At Room Temperature, Gaston Corthey, Jimena A. Olmos-Asar, Gilberto Casillas, Marcelo M. Mariscal, Sergio Mejia-Rosales, Julio C. Azcarate, Eduardo Larios, Miguel Jose-Yacaman, Roberto Salvarezza, M Fonticelli
Australian Institute for Innovative Materials - Papers
The role that protecting molecules have on the way that palladium atoms arrange themselves in nanoparticles prepared at room temperature was studied by the analysis of aberration-corrected scanning transmission electron microscopy images and atomistic Langevin dynamics simulations. It was found that the arrangement of Pd atoms is less ordered in thiolate-protected nanoparticles than in amine-protected ones. The experimental and theoretical data showed that the disorder in ∼3 nm thiolate-protected particles is promoted by the strong S-Pd bond in the sulfide layer that surrounds the nanoparticles.
The Formation Of Nano-Layered Grains And Their Enhanced Superconducting Transition Temperature In Mg-Doped Fese0.9 Bulks, Feng Lan, Zongqing Ma, Yongchang Liu, Ning Chen, Qi Cai, Huijun Li, Shaon Barua, Dipakkumar Patel, Md Shahriar Hossain, Jung Ho Kim, S X. Dou
The Formation Of Nano-Layered Grains And Their Enhanced Superconducting Transition Temperature In Mg-Doped Fese0.9 Bulks, Feng Lan, Zongqing Ma, Yongchang Liu, Ning Chen, Qi Cai, Huijun Li, Shaon Barua, Dipakkumar Patel, Md Shahriar Hossain, Jung Ho Kim, S X. Dou
Australian Institute for Innovative Materials - Papers
To search a proper dopant to further improve superconductivity in 11 type Fe-based superconductors makes sense to both their superconductivity mechanism and possible technological applications. In present work, Mg doped FeSe polycrystalline bulks were obtained by a two-step solid-state reaction method. Even though there are many MgSe and iron impurities existing in the Mg heavy doped FeSe bulks, they exhibit obviously increased Tc compared to undoped FeSe sample. It was found that Mg addition has little effect on the crystal lattice parameters of superconducting beta-FeSe, whereas leads to the formation of nano-layered grain structure consisted of MgSe and beta-FeSe …
Temperature Dependent Photoexcited Carrier Dynamics In Multiferroic Bifeo3 Film: A Hidden Phase Transition, Zeyu Zhang, Zuanming Jin, Qunfeng Pan, Yue Xu, Xian Lin, Guohong Ma, Zhenxiang Cheng
Temperature Dependent Photoexcited Carrier Dynamics In Multiferroic Bifeo3 Film: A Hidden Phase Transition, Zeyu Zhang, Zuanming Jin, Qunfeng Pan, Yue Xu, Xian Lin, Guohong Ma, Zhenxiang Cheng
Australian Institute for Innovative Materials - Papers
The ultrafast carrier dynamics of the multiferroic BiFeO3 film in a broad temperature range is investigated using optical pump-probe spectroscopy. The photoexcited electrons release their energy with optical phonons emission through electron-phonon coupling in about 1 ps. The following intermediate process is identified as dynamical spin-lattice coupling in several picoseconds. Furthermore, the peak values of the optical reflectivity and the time constants of carrier relaxation channels show significant changes while the temperature varies from 137.5 K to around 195 K, this aligns with the previously reported hidden phase transition. Our study demonstrates that ultrafast spectroscopy is a sensitive method to …
High-Temperature Piezoelectric Sensing, Xiaoning Jiang, Kyungrim Kim, Shujun Zhang, Joseph A. Johnson, Giovanni Salazar
High-Temperature Piezoelectric Sensing, Xiaoning Jiang, Kyungrim Kim, Shujun Zhang, Joseph A. Johnson, Giovanni Salazar
Australian Institute for Innovative Materials - Papers
Piezoelectric sensing is of increasing interest for high-temperature applications in aerospace, automotive, power plants and material processing due to its low cost, compact sensor size and simple signal conditioning, in comparison with other high-temperature sensing techniques. This paper presented an overview of high-temperature piezoelectric sensing techniques. Firstly, different types of high-temperature piezoelectric single crystals, electrode materials, and their pros and cons are discussed. Secondly, recent work on high-temperature piezoelectric sensors including accelerometer, surface acoustic wave sensor, ultrasound transducer, acoustic emission sensor, gas sensor, and pressure sensor for temperatures up to 1,250 °C were reviewed. Finally, discussions of existing challenges and …
1-3 Piezoelectric Composites For High-Temperature Transducer Applications, Lili Li, Shujun Zhang, Zhuo Xu, Fei Wen, Xuecang Geng, Hyeong Jae Lee, Thomas R. Shrout
1-3 Piezoelectric Composites For High-Temperature Transducer Applications, Lili Li, Shujun Zhang, Zhuo Xu, Fei Wen, Xuecang Geng, Hyeong Jae Lee, Thomas R. Shrout
Australian Institute for Innovative Materials - Papers
High-temperature Pb(Zr,Ti)O3/epoxy 1-3 composites were fabricated using the dice and fill method. The epoxy filler was modified with glass spheres in order to improve the thermal reliability of the composites at elevated temperatures. Temperature-dependent dielectric and electromechanical properties of the composites were measured after ageing at 250 °C with different dwelling times. Obvious cracks were observed and the electrodes were damaged in the composite with unmodified epoxy after 200 h, leading to the failure of the composite. In contrast, composites with >12 vol% glass sphere loaded epoxies were found to exhibit minimal electrical property variation after ageing for 500 h, …
Effect Of Sintering Temperature On The Superconducting Properties Of Graphene Doped Mgb2, K S B De Silva, X Xu, Sanjeev Gambhir, D C K Wong, W X Li, Q Y. Hu
Effect Of Sintering Temperature On The Superconducting Properties Of Graphene Doped Mgb2, K S B De Silva, X Xu, Sanjeev Gambhir, D C K Wong, W X Li, Q Y. Hu
Australian Institute for Innovative Materials - Papers
A comprehensive study on the effects of sintering temperature on graphene-doped MgB2 superconductor was conducted. Graphene has emerged as an effective dopant that is capable of improving the critical current density (J-{\rm c}) and flux pinning at a very low doping level, with only a slight reduction of the critical temperature (T-{\rm c}). MgB2 undoped and graphene-doped bulk samples were prepared by the in situ method and sintered within a temperature range from 650 to 950 {\circ}\hbox{C}. It is surprising to note that at the doping level of 1 at.% the sample sintered at 850 {\circ}\hbox{C} shows a J\rm c …
Thz Photomixer With A 40-Nm-Wide Nanoelectrode Gap On Low-Temperature Grown Gaas, G Seniutinas, G Gervinskas, E Constable, A Krotkus, G Molis, G Valusis, Roger A. Lewis, S Juodkazis
Thz Photomixer With A 40-Nm-Wide Nanoelectrode Gap On Low-Temperature Grown Gaas, G Seniutinas, G Gervinskas, E Constable, A Krotkus, G Molis, G Valusis, Roger A. Lewis, S Juodkazis
Australian Institute for Innovative Materials - Papers
A terahertz (THz or T-rays) photomixer consisting of a meander type antenna with integrated nanoelectrodes on a low temperature grown GaAs (LT-GaAs) is demonstrated. The antenna was designed for molecular fingerprinting and sensing applications within a spectral range of 0.3-0.4 THz. A combination of electron beam lithography (EBL) and focused ion beam (FIB) milling was used to fabricate the T-ray emitter. Antenna and nanoelectrodes were fabricated by standard EBL and lift-off steps. Then a 40-nm-wide gap in an active photomixer area separating the nanoelectrodes was milled by a FIB. The integrated nano-contacts with nano-gaps enhance the illuminated light and THz …
Rational Design Of P-Type Thermoelectric Pbte: Temperature Dependent Sodium Solubility, Sima Aminorroaya-Yamini, Teruyuki Ikeda, Aaron Lalonde, Yanzhong Pei, S X. Dou, G. Jeffrey Snyder
Rational Design Of P-Type Thermoelectric Pbte: Temperature Dependent Sodium Solubility, Sima Aminorroaya-Yamini, Teruyuki Ikeda, Aaron Lalonde, Yanzhong Pei, S X. Dou, G. Jeffrey Snyder
Australian Institute for Innovative Materials - Papers
We develop a solid understanding of the termperature-dependent solubility of sodium p-type PbTe, the most efficient thermoelectric material. The maximum solubility of socium telluride (NaTe) in PbTe is measured to be 1.4+0.3 at percent and the heat of solution is evaluated and that addresses fundamental issues regarding the formation of nano-precipitates.
In-Situ Observation Of Nanomechanical Behavior Arising From Critical-Temperature-Induced Phase Transformation In Ba(Zr0.2ti 0.8)O3-0.5(Ba0.7ca0.3)Tio 3 Thin Film, Z M. Wang, Zh L. Cai, K Zhao, X L. Guo, J Chen, W Sun, Zh X. Cheng, H Kimura, B Li, G L. Yuan, J Yin, Zh G. Liu
In-Situ Observation Of Nanomechanical Behavior Arising From Critical-Temperature-Induced Phase Transformation In Ba(Zr0.2ti 0.8)O3-0.5(Ba0.7ca0.3)Tio 3 Thin Film, Z M. Wang, Zh L. Cai, K Zhao, X L. Guo, J Chen, W Sun, Zh X. Cheng, H Kimura, B Li, G L. Yuan, J Yin, Zh G. Liu
Australian Institute for Innovative Materials - Papers
In this Letter, we use the nanoindentation technique and vary the testing temperature to above and below critical values to study the nanomechanical features of a strong Pb-free piezoelectric Ba(Zr0.2Ti 0.8)O3-0.5(Ba0.7Ca0.3)TiO 3 (BZT-0.5BCT) thin film across its piezoelectric-optimal morphotropic phase boundary. The mechanisms responsible for the Young's modulus and hardness evolution are then discussed. An X-ray diffraction method that can detect the d(110) variation associated with the change in the inclination angle ψ of the (110) plane was developed to quantify the residual stress in the BZT-0.5BCT films.
A Study Of Tio2 Binder-Free Paste Prepared For Low Temperature Dye-Sensitized Solar Cells, Jeremy H. Yune, Inna Karatchevtseva, Gerri Triani, Klaudia Wagner, David Officer
A Study Of Tio2 Binder-Free Paste Prepared For Low Temperature Dye-Sensitized Solar Cells, Jeremy H. Yune, Inna Karatchevtseva, Gerri Triani, Klaudia Wagner, David Officer
Australian Institute for Innovative Materials - Papers
A binder-free titania paste was prepared by chemical modification of an acidic TiO2 sol with ammonia. By varying the ammonia concentration, the viscosity of the acidic TiO2 suspension increased, thereby allowing uniform films to be cast. The photoelectrochemical performance of TiO2 electrodes, cast as single layers, was dependent on the thermal treatment cycle. Fourier transform infrared spectroscopy was used to characterize the extent of residual organics and found that acetates from the TiO2 precursor preparation were retained within the electrode structure after thermal treatment at 150 °C. Electrodes of nominal thickness 4 lm produced an energy conversion efficiency as high …
Lini0.5mn1.5o4 Spinel Cathode Using Room Temperature Ionic Liquid As Electrolyte, Xuan-Wen Gao, Chuanqi Feng, Shulei Chou, Jia-Zhao Wang, Jia-Zeng Sun, Maria Forsyth, Doug Mcfarlane, Hua-Kun Liu
Lini0.5mn1.5o4 Spinel Cathode Using Room Temperature Ionic Liquid As Electrolyte, Xuan-Wen Gao, Chuanqi Feng, Shulei Chou, Jia-Zhao Wang, Jia-Zeng Sun, Maria Forsyth, Doug Mcfarlane, Hua-Kun Liu
Australian Institute for Innovative Materials - Papers
In this study, LiNi0.5Mn1.5O4 (LNMO) nanoparticles were prepared as a 5 V cathode material via a rheological phase method and annealed at different temperatures: 680 ◦C, 750 ◦C, and 820 ◦C. The sample annealed at 750 ◦C shows the best performance. A room temperature ionic liquid (RTIL) containing 1 M lithium bis(trifluoromethanesulfonyl) imide (LiNTf2) in N-butyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl) imide (C4mpyrNTf2) was used as novel electrolyte in conjunction with the LNMO cathodes and their electrochemical properties have been investigated. The results show that the LNMO using RTIL as electrolyte has better coulombic efficiency and comparable discharge capacities to those of the cells …
Temperature And Frequency Dependent Giant Magnetodielectric Coupling In Dymn0.33fe0.67o3, Fang Hong, Zhenxiang Cheng, Xiaolin Wang
Temperature And Frequency Dependent Giant Magnetodielectric Coupling In Dymn0.33fe0.67o3, Fang Hong, Zhenxiang Cheng, Xiaolin Wang
Australian Institute for Innovative Materials - Papers
Perovskite DyMn0.33Fe0.67O3 experiences a paramagnetism-antiferromagnetism transition at 450K and spin reorientation at 290 K. Magnetodielectric properties were studied around the spin reorientation transition. Both giant positive and giant negative magnetodielectric coupling (MDC) were observed near room temperature. The MDC shows strong temperature and frequency dependence, and the sign changes from positive to negative when magnetic state transits from a canted antiferromagnetic state to a collinear antiferromagnetic state. Possible mechanisms are proposed based on the Maxwell-Wagner model, phase transition, the magnetoresistance effect, and spin-phonon coupling.