Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 11 of 11
Full-Text Articles in Engineering
Improved Controller For High Temperature Super Conducting Magnetic Energy Storage (Hts-Smes), Danny Soetanto, M V. Aware
Improved Controller For High Temperature Super Conducting Magnetic Energy Storage (Hts-Smes), Danny Soetanto, M V. Aware
Faculty of Engineering - Papers (Archive)
This paper describes a novel controller for a High Temperature Superconducting Magnetic Energy Storage (HTSSMES) that can ensure (a) fast return of energy to the superconducting coil under constant current mode and (b) a constant and sinusoidal input supply current irrespective of the varying load demand with and without harmonics. A special feature of this controller is its ability to smoothly charge the superconducting coil using constant current charging so that it can be ready for the next discharging operation as soon as possible. Analysis of the circuit operation under hysteresis control is presented in details. Simulation and experimental results …
Superconducting Magnetic Energy Storage Systems For Power System Applications, Danny Soetanto, K.W.E Cheng
Superconducting Magnetic Energy Storage Systems For Power System Applications, Danny Soetanto, K.W.E Cheng
Faculty of Engineering - Papers (Archive)
Advancement in both superconducting technologies and power electronics led to High Temperature Superconducting Magnetic Energy Storage Systems (SMES) having some excellent performances for use in power systems, such as rapid response (millisecond), high power (multi-MW), high efficiency, and four- quadrant control. This paper provides a review on SMES applications to power systems.
Effect Of Zn Doping On Magnetic Order And Superconductivity In Lafeaso, Yuke Li, Xiao Lin, Qian Tao, Cao Wang, Tong Zhou, Linjun Li, Qingbo Wang, Mi He, Guanghan Cao, Zhu-An Xu
Effect Of Zn Doping On Magnetic Order And Superconductivity In Lafeaso, Yuke Li, Xiao Lin, Qian Tao, Cao Wang, Tong Zhou, Linjun Li, Qingbo Wang, Mi He, Guanghan Cao, Zhu-An Xu
Faculty of Engineering - Papers (Archive)
We report Zn-doping effect in the parent and F-doped LaFeAsO oxy-arsenides. Slight Zn doping in LaFe1−xZnxAsO drastically suppresses the resistivity anomaly around 150K associated with the antiferromagnetic (AFM) spin density wave (SDW) in the parent compound. The measurements of magnetic susceptibility and thermopower confirm further the effect of Zn doping on AFM order. Meanwhile Zn doping does not affect or even enhances the Tc of LaFe1−xZnxAsO0.9F0.1, in contrast to the effect of Zn doping in high-Tc cuprates. We found that the solubility of Zn content (x) is limited to less than 0.1 in both systems and further Zn doping (i.e. …
Flux Distribution At The Cross Section Of Stacked Nanostructured Magnetic Ribbon, Zhi Wei Lin, Jian Guo Zhu, Youguang Guo, Tom H. Johansen, Y. Yoshizawa
Flux Distribution At The Cross Section Of Stacked Nanostructured Magnetic Ribbon, Zhi Wei Lin, Jian Guo Zhu, Youguang Guo, Tom H. Johansen, Y. Yoshizawa
Faculty of Engineering - Papers (Archive)
Conventional magnetization methods only measure the average magnetic properties over the whole sample. The information is insufficient to understand the local character. This paper presents the visualized magnetization process and its profiles in detail at the cross section of the FINEMET ribbon using advanced magnetooptical imaging technique. External magnetic fields were applied parallel to the surface of the ribbon. A magnetization curve was plotted by interpreting the profile of intensity of magnetooptical images. The profile indicates that the flux densities are higher at the cross section of the ribbons compared with those at the gaps between the ribbons. The flux …
Hydrothermal Synthesis And Optical, Magnetic And Supercapacitance Properties Of Nanoporous Cobalt Oxide Nanorodes, Guoxiu Wang, Xiaoping Shen, Josip Horvat, Bei Wang, Hao Liu, David Wexler, Jane Yao
Hydrothermal Synthesis And Optical, Magnetic And Supercapacitance Properties Of Nanoporous Cobalt Oxide Nanorodes, Guoxiu Wang, Xiaoping Shen, Josip Horvat, Bei Wang, Hao Liu, David Wexler, Jane Yao
Faculty of Engineering - Papers (Archive)
Nanoporous cobalt oxide nanorods were synthesized by a hydrothermal method. Transmission electron microscopy analysis showed that the individual Co3O4 nanorods have a nanoporous structure, consisting of the textured aggregations of nanocrystals. Optical properties of Co3O4 nanorods were characterized by Raman and UV−vis spectroscopy. Magnetic property measurement shows that Co3O4 nanorods have a low Néel transition temperature of 35 K. We observed quite significant exchange bias for nanoporous Co3O4 nanorods, indicating the existence of magnetic coupling between the nanocrystals in Co3O4 nanorods. When applied as electrode …
Magnetic Glassy Behaviour In Ferroelectric Relaxor Type Solid Solutions: Magnetelectric Relaxor, Zhenxiang Cheng, Xiaolin Wang, Gustavo A. Alvarez, S. X. Dou, Shujun Zhang, Thomas R. Shrout
Magnetic Glassy Behaviour In Ferroelectric Relaxor Type Solid Solutions: Magnetelectric Relaxor, Zhenxiang Cheng, Xiaolin Wang, Gustavo A. Alvarez, S. X. Dou, Shujun Zhang, Thomas R. Shrout
Faculty of Engineering - Papers (Archive)
Perovskite solid solution ceramics with compositions of 0.9Pb(Fe0.5Nb0.5)O3–0.1PbTiO3, 0.6Pb(Ni1/3Nb2/3)O3–0.4PbTiO3, and 0.6Pb(Co1/3Nb2/3)O3–0.4PbTiO3 were synthesized by the traditional solid state reaction method. Ferroelectric measurements revealed that these samples have well saturated polarization-electrical field loops. Dielectric measurements showed that abnormal dielectric peaks at their Curie temperature were frequency dependent. Both characteristics indicate that these samples are relaxor type ferroelectric materials. Field cooled and zero field cooled magnetization measurements revealed that the 0.6Pb(Ni1/3Nb2/3)O3–0.4PbTiO3 and …
Increased Superconductivity For Cnt Doped Mgb2 Sintered In 5t Pulsed Magnetic Field, Wenxian Li, Ying Li, Rong Hua Chen, Rong Zeng, Lin Lu, Yun Zhang, Michael Tomsic, Matthew Rindfleisch, S. X. Dou
Increased Superconductivity For Cnt Doped Mgb2 Sintered In 5t Pulsed Magnetic Field, Wenxian Li, Ying Li, Rong Hua Chen, Rong Zeng, Lin Lu, Yun Zhang, Michael Tomsic, Matthew Rindfleisch, S. X. Dou
Faculty of Engineering - Papers (Archive)
The superconductivity of carbon nanotube (CNT) doped MgB2 sintered in pulsed magnetic field (PMF) was investigated with Raman scattering measurements and Raman spectral fit analysis. Although the carbon (C) substitution for the boron (B) is increased for the sample sintered in PMF, its superconductivity is advanced comparing with the sample sintered without PMF. The improved critical transition temperature, Tc, is attributed to the strengthening of the electron-phonon coupling (EPC) in MgB2, as reflected by the broadened E 2g mode in the Raman spectra, because the carbon atoms are homogeneously distributed in the boron planes.
Magnetic Phase Transitions In Pr1-Xluxmn2ge2 Compounds, S X. Dou, Jianli Wang, Maxim Avdeev, A J Studer, Rong Zeng, Stewart J. Campbell
Magnetic Phase Transitions In Pr1-Xluxmn2ge2 Compounds, S X. Dou, Jianli Wang, Maxim Avdeev, A J Studer, Rong Zeng, Stewart J. Campbell
Faculty of Engineering - Papers (Archive)
The effects of replacing Pr by Lu on the magnetic behaviour and structures of Pr1−xLuxMn2Ge2 (x = 0.2,x = 0.4) have been investigated using x-ray diffraction, Mössbauer spectroscopy, magnetization and neutron diffraction measurements. The substitution of Lu for Pr leads to a decrease in the lattice constants a, c and the unit cell volume V at room temperature with this contraction of the unit cell resulting in modifications of the Pr1−xLuxMn2Ge2 magnetic structures. Four and five magnetic phase transitions—linked primarily with …
Magnetic Properties And Magnetocaloric Effect Of (Mn1-Xnix)3sn2(X=0-0.5) Compounds, Rong Zeng, Lin Lu, Jung Ho Kim, Dongqi Shi, Hua-Kun Liu, S. X. Dou, Jianli Wang, Stewart J. Campbell, Zhaoxiang Wang, Y Li, Wenxian Li, M Y. Zhu, Chuanqi Feng
Magnetic Properties And Magnetocaloric Effect Of (Mn1-Xnix)3sn2(X=0-0.5) Compounds, Rong Zeng, Lin Lu, Jung Ho Kim, Dongqi Shi, Hua-Kun Liu, S. X. Dou, Jianli Wang, Stewart J. Campbell, Zhaoxiang Wang, Y Li, Wenxian Li, M Y. Zhu, Chuanqi Feng
Faculty of Engineering - Papers (Archive)
The effects of Ni substitution on the magnetic properties and magnetocaloric effect (MCE) of (Mn1−xNix)3Sn2 compounds (x = 0–0.5) have been investigated by x-ray diffraction and magnetization measurements. It was found that Ni substitution decreases the crystal cell volume and the magnetic transition temperatures compared with pure Mn3Sn2. The MCE for all samples has been calculated from the magnetization data in terms of the isothermal magnetic entropy change ΔSM. The maximum values of ΔSMmax at the magnetic phase transition temperatures resulting …
Flux Pinning Of Stress Induced Magnetic Inhomogeneity In The Bilayers Of Yba2cu3o7-Δ/La0.67sr0.33mno3-Δ, S X. Dou, Rong Zeng, Y M. Lu, L Peng, B Gao, Z Y. Liu, F Fan, C B. Cai, C Z. Chen
Flux Pinning Of Stress Induced Magnetic Inhomogeneity In The Bilayers Of Yba2cu3o7-Δ/La0.67sr0.33mno3-Δ, S X. Dou, Rong Zeng, Y M. Lu, L Peng, B Gao, Z Y. Liu, F Fan, C B. Cai, C Z. Chen
Faculty of Engineering - Papers (Archive)
Elaborately designed bilayers consisting of epitaxial YBa2Cu3O7-δ (YBCO) and La0.67Sr0.33MnO3-δ (LSMO) films were fabricated by pulsed laser deposition with respect to the investigation into magnetic-dependent vortex pinning effect. The improvement in the critical current density and a pronounced upward shift in the superconducting irreversibility line based on magnetotransport measurements are observed when compared to the pure YBCO film, suggesting the enhancement in flux pinning in the studied bilayer. It is believed that the improved flux pinning for YBCO arises from the magnetic inhomogeneity of the underlying LSMO. Magnetization measurements show …
Colloidal Transport On Magnetic Garnet Filmsw, Tierno Pietro, Frances Sagues, Tom H. Johansen, Thomas Fischer
Colloidal Transport On Magnetic Garnet Filmsw, Tierno Pietro, Frances Sagues, Tom H. Johansen, Thomas Fischer
Faculty of Engineering - Papers (Archive)
This article reports several recent discoveries related to the controlled transport of paramagnetic colloidal particles above magnetic garnet films. The garnet films are thin uniaxial ferromagnetic films in which ferromagnetic domains can be organized into symmetric patterns consisting of stripes or bubbles and generate strong local magnetic field gradients. Application of an external homogeneous magnetic field on a larger scale compared to the spatial periodicity of the magnetic pattern in the film modulates the potential generated at its surface and induces the controlled motion of colloidal particles placed above the film. Several novel dynamical regimes are observed and reported, from …