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Full-Text Articles in Physical Sciences and Mathematics
Giant Enhancement In Critical Current Density, Up To A Hundredfold, In Superconducting Nafe0.97co0.03 As Single Crystals Under Hydrostatic Pressure, Babar Shabbir, Xiaolin Wang, Shaban Reza Ghorbani, A-Li Wang, S X. Dou, X.H Chen
Giant Enhancement In Critical Current Density, Up To A Hundredfold, In Superconducting Nafe0.97co0.03 As Single Crystals Under Hydrostatic Pressure, Babar Shabbir, Xiaolin Wang, Shaban Reza Ghorbani, A-Li Wang, S X. Dou, X.H Chen
Australian Institute for Innovative Materials - Papers
Tremendous efforts towards improvement in the critical current density "Jc" of iron based superconductors (FeSCs), especially at relatively low temperatures and magnetic fields, have been made so far through different methods, resulting in real progress. Jc at high temperatures in high fields still needs to be further improved, however, in order to meet the requirements of practical applications. Here, we demonstrate a simple approach to achieve this. Hydrostatic pressure can significantly enhance Jc in NaFe0.97Co0.03As single crystals by at least tenfold at low field and more than a hundredfold at high fields. …
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 …
Probe Current Determination In Analytical Tem/Stem And Its Application To The Characterization Of Large Area Eds Detectors, David R. G Mitchell, Mitchell John Bromley Nancarrow
Probe Current Determination In Analytical Tem/Stem And Its Application To The Characterization Of Large Area Eds Detectors, David R. G Mitchell, Mitchell John Bromley Nancarrow
Australian Institute for Innovative Materials - Papers
A simple procedure, which enables accurate measurement of transmission electron microscopy (TEM)/STEM probe currents using an energy loss spectrometer drift tube is described. The currents obtained are compared with those measured on the fluorescent screen to enable the losses due to secondary and backscattered electrons to be determined. The current values obtained from the drift tube allow the correction of fluorescent screen current densities to yield true current. They also enable CCD conversion efficiencies to be obtained, which in turn allows images to be calibrated in terms of electron fluence. Using probes of known current in conjunction with a NiO …
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 …
Improving Fault Ride-Through Capability Of Dfig Based Wind Generators By Using Bridge-Type Superconducting Fault Current Limiter, Mehrdad Tarafdar Hagh, Kashem M. Muttaqi, Danny Sutanto, Md Shahriar Hossain, Ahmed M. Haidar
Improving Fault Ride-Through Capability Of Dfig Based Wind Generators By Using Bridge-Type Superconducting Fault Current Limiter, Mehrdad Tarafdar Hagh, Kashem M. Muttaqi, Danny Sutanto, Md Shahriar Hossain, Ahmed M. Haidar
Australian Institute for Innovative Materials - Papers
This paper proposes series connection of a diode bridge-type superconducting fault current limiter (SFCL) with rotor side converter (RSC) of a double fed induction generator (DFIG) based wind turbine. The proposed SFCL improves the fault ride through (FRT) capability of DFIG and prevents the RSC from damaging fault currents. Because of using superconductor DC coil, there is not any power loss during fault or normal operation of system. The proposed SFCL does not have any considerable affect in wind turbine's operation during normal condition. It is not necessary to use any measurement and control systems, too. The SFCL returns to …
Hydrostatic Pressure: A Very Effective Approach To Significantly Enhance Critical Current Density In Granular Iron Pnictide Superconductors, Babar Shabbir, Xiaolin Wang, Shaban Reza Ghorbani, C Shekhar, S X. Dou, O.N Srivastava
Hydrostatic Pressure: A Very Effective Approach To Significantly Enhance Critical Current Density In Granular Iron Pnictide Superconductors, Babar Shabbir, Xiaolin Wang, Shaban Reza Ghorbani, C Shekhar, S X. Dou, O.N Srivastava
Australian Institute for Innovative Materials - Papers
Pressure is well known to significantly raise the superconducting transition temperature, Tc, in both iron pnictides and cuprate based superconductors. Little work has been done, however, on how pressure can affect the flux pinning and critical current density in the Fe-based superconductors. Here, we propose to use hydrostatic pressure to significantly enhance flux pinning and Tc in polycrystalline pnictide bulks. We have chosen Sr4V2O6Fe2As2 polycrystalline samples as a case study. We demonstrate that the hydrostatic pressure up to 1.2 GPa can not only significantly increase Tc from …
Mgb2 Superconducting Joints For Persistent Current Operation, Dipakkumar Patel, Md S. Hossain, Khay Wai W. See, Xun Xu, Shaon Barua, Zongqing Ma, Seyong Choi, Mike Tomsic, Jung Ho Kim
Mgb2 Superconducting Joints For Persistent Current Operation, Dipakkumar Patel, Md S. Hossain, Khay Wai W. See, Xun Xu, Shaon Barua, Zongqing Ma, Seyong Choi, Mike Tomsic, Jung Ho Kim
Australian Institute for Innovative Materials - Papers
High-performance superconducting joints are essential for realizing persistent-mode magnets. Herein, we propose a concept and fabrication of such superconducting joints, which yielded reliable performance in the operating temperature range of 4.2-25 K. MgB2-MgB2 joints in magnets are known to result in deterioration of localized electrical, thermal, and mechanical properties. To overcome these problems, the ends of the two wires are inserted into a pellet press, which is then filled with a mixture of unreacted magnesium and boron powders, followed by heat treatment. The critical current capacity and joint resistance were precisely evaluated by the standard four-probe method …