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Full-Text Articles in Engineering

Magnetic Properties And Microstructures Of Iron Oxide@Mesoporous Silica Core-Shell Composite For Applications In Magnetic Dye Separation, Weichang Hao, Yang Xi, Jingwei Hu, Tianmin Wang, Yi Du, X L. Wang Jan 2012

Magnetic Properties And Microstructures Of Iron Oxide@Mesoporous Silica Core-Shell Composite For Applications In Magnetic Dye Separation, Weichang Hao, Yang Xi, Jingwei Hu, Tianmin Wang, Yi Du, X L. Wang

Australian Institute for Innovative Materials - Papers

"In this report, hollow mesoporous silica (HMS) and iron oxide-hollow mesoporous silica (FexOy@HMS) core-shell composite were prepared by a one-step facile fabrication method. Transmission electron microscopy, X-ray diffraction, N-2 adsorption-desorption isotherms, and vibrating sample magnetometer were used to characterize the morphology, microstructure, and magnetic properties of the HMS and core-shell composite. The magnetic separability of FexOy@HMS core-shell composite was tested in Rhodamine B (Rh. B) dye solution. The results indicate that the core-shell composite can absorb Rh. B dyes molecules effectively up to 90.1%. (C) 2012 American Institute of Physics. [doi:10.1063/1.3670049]"


Magnetic And Superconducting Properties Of Spin-Fluctuation-Limited Superconducting Nanoscale Vnx, R Zeng, J Liu, G Du, W. X. Li, J Wang, J Horvat, S X. Dou Jan 2012

Magnetic And Superconducting Properties Of Spin-Fluctuation-Limited Superconducting Nanoscale Vnx, R Zeng, J Liu, G Du, W. X. Li, J Wang, J Horvat, S X. Dou

Australian Institute for Innovative Materials - Papers

"VNx nanoparticles and nanowires have been prepared by nitrifying V2O5 nanoparticles (NP) and nanowires (NW). The V2O5 NP and NW were synthesized by a facile hydrothermal method. Magnetic susceptibility (chi) and magnetization measurements showed long range superconducting ordering (LRSO) at the temperature of 5.8 K for NW, but there was no observation of LRSO (at least down to 2 K) for the NP sample, which is a much lower temperature than for the corresponding bulk, while both NP and NW showed the absence of long range magnetic ordering, at least down to 2 K. However, the chi data showed that …


"Density Of States, Magnetic And Transport Properties Of Nd Doped Two Dimensional Perovskite Compound Sr2coo4", Qiwen Yao, Hideo Kimura, Xiaolin Wang, Kosta Konstantinov, Hongyang Zhao, Hai Qiu, Rumi Tanahashi, Kiyoshi Ozawa, S. X. Dou Jan 2012

"Density Of States, Magnetic And Transport Properties Of Nd Doped Two Dimensional Perovskite Compound Sr2coo4", Qiwen Yao, Hideo Kimura, Xiaolin Wang, Kosta Konstantinov, Hongyang Zhao, Hai Qiu, Rumi Tanahashi, Kiyoshi Ozawa, S. X. Dou

Faculty of Engineering - Papers (Archive)

"Structures, transport, magnetic properties, and first principle calculation results will be reported for the two dimensional layered structured perovskite compounds Sr2-xNdxCoO4 (x = 0.5, 0.75, 1, 1.25). Structure refinement results revealed that these compounds crystallized in K2NiF4-type structures with space group I4/mmm. The temperature dependence of resistivity showed semiconductor like behavior for these samples. It was found that the lattice parameter c decreases as the doping level x increases. The compounds exhibited a paramagnetic to ferromagnetic transition at temperatures of about 170, 125 K for the x = 1 and 0.75 samples, respectively. The temperature dependence of resistivity for the …


Growth Mechanism And Magnetic Properties Of Highly Crystalline Nio Nanocubes And Nanorods Fabricated By Evaporation, Dapeng Chen, Xiaolin Wang, Yi Du, Song Ni, Zi-Bin Chen, Xiaozhou Liao Jan 2012

Growth Mechanism And Magnetic Properties Of Highly Crystalline Nio Nanocubes And Nanorods Fabricated By Evaporation, Dapeng Chen, Xiaolin Wang, Yi Du, Song Ni, Zi-Bin Chen, Xiaozhou Liao

Faculty of Engineering - Papers (Archive)

A new approach to the preparation of regularly shaped NiO nanocubes and nanorods by an infrared heating evaporation method is presented. The growth model is proposed to be a vapor−solid mechanism. The morphology of the nanocrystals can be tuned by the carrier gas flow rate. The samples consist of nanocrystals that are highly crystallized with atomic-scale smooth surfaces. This novel method could be extended to nanocrystal growth of other oxides with low volatility or high melting points. The results of magnetic characterization indicate that the NiO nanorods and nanocubes grown from a mixed target both show weak ferromagnetic states at …


"Oxygen-Vacancy Effect On Structural, Magnetic, And Ferroelectric Properties In Multiferroic Ymno3 Single Crystals", Dapeng Chen, Yi Du, Xiaolin Wang, Zhenxiang Cheng, S. X. Dou, Zhi W. Lin, Jian G. Zhu, Bo Xu Jan 2012

"Oxygen-Vacancy Effect On Structural, Magnetic, And Ferroelectric Properties In Multiferroic Ymno3 Single Crystals", Dapeng Chen, Yi Du, Xiaolin Wang, Zhenxiang Cheng, S. X. Dou, Zhi W. Lin, Jian G. Zhu, Bo Xu

Faculty of Engineering - Papers (Archive)

"We have investigated the structural, magnetic, and ferroelectric properties of magnetically frustrated multiferroic YMnO3 single crystals. The ferroelectric domain structures of YMnO3 samples were studied by piezoresponse force microscopy. Instead of domain vortex structure in stoichiometric crystals, YMnO3-delta exhibits a random domain configuration with straight domain walls. In magnetic measurements, the YMnO3-delta crystal shows typical antiferromagnetic behavior with higher Neel temperature and lower magnetization compared to the stoichiometric sample. The ordered oxygen vacancies dominate multiferroicity through tailoring the domain wall structure. (C) 2012 American Institute of Physics. [doi:10.1063/1.3676000]"


Structural Properties And Magnetic Phase Transition In Honi2mn (57fe), Jianli Wang, Stewart J. Campbell, M Hofmann, M Hoelzel, Rong Zeng, S. X. Dou, S J. Kennedy Jan 2012

Structural Properties And Magnetic Phase Transition In Honi2mn (57fe), Jianli Wang, Stewart J. Campbell, M Hofmann, M Hoelzel, Rong Zeng, S. X. Dou, S J. Kennedy

Faculty of Engineering - Papers (Archive)

"The structural and magnetic properties of HoNi2Mn (57Fe) have been investigated.The Fe-57-doped HoNi2Mn compound crystallizes in the MgCu2-type structure with Fd-3m space group similar to HoNi2 and HoMn2.HoNi2Mn (57Fe) exhibits ferrimagnetic ordering below a Curie temperature of T-C similar to 60 K-significantly higher than the corresponding values for HoNi2 (T-C - 15 K) and HoMn2 (T-C 24 K)-with analyses of dc magnetization and ac susceptibility results confirming that the magnetic transition at T-C is second order.The Mossbauer spectra above T-C are described well by two sub-spectra representing the 8a and 16d sites while below T-C the spectra have been fitted …


Terahertz Magnetic Field Induced Coherent Spin Precession In Yfeo3, Runze Zhou, Zuanming Jin, Gaofang Li, Guohong Ma, Zhenxiang Cheng, Xiaolin Wang Jan 2012

Terahertz Magnetic Field Induced Coherent Spin Precession In Yfeo3, Runze Zhou, Zuanming Jin, Gaofang Li, Guohong Ma, Zhenxiang Cheng, Xiaolin Wang

Faculty of Engineering - Papers (Archive)

We present the magnetic dipole transition at 0.299 THz excited by magnetic component of terahertz electromagnetic pulse in an antiferromagnetic YFeO3 crystal. The impulsive magnetic field of the terahertz pulse tilts the macroscopic magnetization, causing deviation from the equilibrium position, which is manifested by a sharp absorption at the frequency of the quasiferromagnetic mode of the crystal. The rotating coherent macroscopic magnetization radiates elliptically polarized emission at the frequency of the quasiferromagnetic resonance due to the dichroic absorption in the crystal.


Spatial Dispersion Management In Three-Dimensional Drawn Magnetic Metamaterials, Alessandro Tuniz, Benjamin Pope, Alexander Argyros, Simon Fleming, Anna Wang, Maryanne C. J Large, Elise M. Pogson, Roger A. Lewis, Avi Bendavid, Boris T. Kuhlmey Jan 2012

Spatial Dispersion Management In Three-Dimensional Drawn Magnetic Metamaterials, Alessandro Tuniz, Benjamin Pope, Alexander Argyros, Simon Fleming, Anna Wang, Maryanne C. J Large, Elise M. Pogson, Roger A. Lewis, Avi Bendavid, Boris T. Kuhlmey

Faculty of Engineering - Papers (Archive)

We characterize resonances of 3D fiber metamaterials under transmittance at oblique incidence. The resonance frequency of longitudinally invariant resonators increases with the incident angle, while the resonance of disconnected resonators does not. © 2012 OSA.


Investigation On Welding Arc Interruptions In The Presence Of Magnetic Fields: Arc Length, Torch Angle And Current Pulsing Frequency Influence, Ruham Pablo Reis, Americo Scotti, John Norrish, Dominic Cuiuri Jan 2012

Investigation On Welding Arc Interruptions In The Presence Of Magnetic Fields: Arc Length, Torch Angle And Current Pulsing Frequency Influence, Ruham Pablo Reis, Americo Scotti, John Norrish, Dominic Cuiuri

Faculty of Engineering and Information Sciences - Papers: Part A

Arc interruptions have been observed in tandem pulsed gas metal arc welding (GMAW). This fact, which is likely related to magnetic interaction between the arcs, motivated previous study concerning the influence of the welding current on this phenomenon. In order to promote further understanding, this paper investigates the effects of arc length, torch angle, and high-frequency current pulsing on the arc resistance to extinction. To mimic the situation found in tandem GMAW (magnetic field induced by one arc acting on the other arc), external magnetic fields were applied to gas tungsten arc welding arcs. It was verified that short arc …


Complementary Techniques For Probing Terahertz Magnetic Excitations In Cu3bi(Seo3)2o2cl, K H. Miller, E Constable, H Berger, D B. Tanner, J Horvat, R A. Lewis Jan 2012

Complementary Techniques For Probing Terahertz Magnetic Excitations In Cu3bi(Seo3)2o2cl, K H. Miller, E Constable, H Berger, D B. Tanner, J Horvat, R A. Lewis

Faculty of Engineering and Information Sciences - Papers: Part A

A low frequency magnetic excitation in Cu3Bi(SeO 3)2O2Cl has been studied through complementary spectroscopic techniques which utilised terahertz radiation from a synchrotron, a mercury arc lamp, and a two-colour photomixing system. The excitation has been studied at temperatures down to 5K and in magnetic fields up to 10T. © 2012 IEEE.


Effect Of A Static Magnetic Field On Nanodosimetric Quantities In A Dna Volume, Peter Lazarakis, Marion U. Bug, Elisabetta Gargioni, Susanna Guatelli, Sabastien Incerti, Hans Rabus, Anatoly B. Rosenfeld Jan 2012

Effect Of A Static Magnetic Field On Nanodosimetric Quantities In A Dna Volume, Peter Lazarakis, Marion U. Bug, Elisabetta Gargioni, Susanna Guatelli, Sabastien Incerti, Hans Rabus, Anatoly B. Rosenfeld

Faculty of Engineering - Papers (Archive)

Abstract Purpose: With the advent of magnetic resonance imaging (MRI)-guided radiation therapy it is becoming increasingly important to consider the potential influence of a magnetic field on ionising radiation. This paper aims to study the effect of a magnetic field on the track structure of radiation to determine if the biological effectiveness may be altered. Methods: Using the Geant4-DNA (GEometry ANd Tracking 4) Monte Carlo simulation toolkit, nanodosimetric track structure parameters were calculated for electrons, protons and alpha particles moving in transverse magnetic fields up to 10 Tesla. Applying the model proposed by Garty et al., the track structure parameters …


The Magnetic Structure Of An Epitaxial Bimn 0.5fe 0.5o 3 Thin Film On Srtio 3 (001) Studied With Neutron Diffraction, David Laurence Cortie, A Pj Stampfl, F Klose, Y Du, Xiaolin Wang, H Zhao, H Kimura, Z Cheng Jan 2012

The Magnetic Structure Of An Epitaxial Bimn 0.5fe 0.5o 3 Thin Film On Srtio 3 (001) Studied With Neutron Diffraction, David Laurence Cortie, A Pj Stampfl, F Klose, Y Du, Xiaolin Wang, H Zhao, H Kimura, Z Cheng

Australian Institute for Innovative Materials - Papers

High-angle neutron diffraction was used to directly reveal the atomic-scale magnetic structure of a single-crystalline BiMn 0.5 Fe 0.5 O 3 thin film deposited on a SrTiO 3 (001) substrate. The BiMn 0.5 Fe 0.5 O 3 phase exhibits distinctive magnetic properties that differentiate it from both parent compounds: BiFeO 3 and BiMnO 3. A transition to long-range G-type antiferromagnetism was observed below 120 K with a (1 2 1 2 1 2) propagation vector. A weak ferromagnetic behavior was measured at low temperature by superconducting quantum interference device (SQUID) magnetometry. There is no indication of the spin cycloid, known …


Abnormal Magnetic Behaviors And Large Magnetocaloric Effect In Mnps3 Nanoparticles, R Zeng, S Q. Wang, G D. Du, Jianli Wang, J C. Debnath, Precious Shamba, Z Y. Fang, S. X. Dou Jan 2012

Abnormal Magnetic Behaviors And Large Magnetocaloric Effect In Mnps3 Nanoparticles, R Zeng, S Q. Wang, G D. Du, Jianli Wang, J C. Debnath, Precious Shamba, Z Y. Fang, S. X. Dou

Faculty of Engineering - Papers (Archive)

A nanostructured honeycomb lattice consisting of MnPS3 nanoparticles synthesized via the ion-exchange technique was found to have restacked molecular layers stabilized by H2O insertion between the layers. Susceptibility (χ) and heat capacity measurements showed the absence of long range magnetic ordering, at least down to 2 K. However, the χ data showed that the system possesses a high effective Curie temperature, suggesting that the system is in a high spin lattice disordered state. Evaluation of the magnetocaloric effect indicates that the system has a large reversible magnetic-entropy change (−ΔSm) of 6.8 and 12.8 J/kg K …


Infrared Phonon Anomaly And Magnetic Excitations In Single-Crystal Cu3bi(Seo3)2o2cl, K H. Miller, P W. Stephens, C Martin, E Constable, R A. Lewis, H Berger, G L. Carr, D B. Tanner Jan 2012

Infrared Phonon Anomaly And Magnetic Excitations In Single-Crystal Cu3bi(Seo3)2o2cl, K H. Miller, P W. Stephens, C Martin, E Constable, R A. Lewis, H Berger, G L. Carr, D B. Tanner

Faculty of Engineering - Papers (Archive)

nfrared reflection and transmission as a function of temperature have been measured on single crystals of Cu3Bi(SeO3)2O2Cl. The complex dielectric function and optical properties along all three principal axes of the orthorhombic cell were obtained via Kramers-Kronig analysis and by fits to a Drude-Lorentz model. Below 115 K, 16 additional modes [8(E∥â)+6(E∥b̂)+2(E∥ĉ)] appear in the phonon spectra; however, powder x-ray diffraction measurements do not detect a new structure at 85 K. Potential explanations for the new phonon modes are discussed. Transmission in the far infrared as a function of temperature has revealed …


Magnetic Propulsion Of A Spiral-Type Endoscopic Microrobot In A Real Small Intestine, Hao Zhou, Gursel Alici, Trung Duc Than, Weihua Li, Sylvain Martel Jan 2012

Magnetic Propulsion Of A Spiral-Type Endoscopic Microrobot In A Real Small Intestine, Hao Zhou, Gursel Alici, Trung Duc Than, Weihua Li, Sylvain Martel

Faculty of Engineering - Papers (Archive)

This paper reports on the magnetic propulsion of a spiral-type endoscopic mircorobot in a real small intestine. Magnetic modeling was carried out to design and commission an external electromagnetic system, which wirelessly provides power to the robotic agent. The capsules with different spiral structures were magnetically propelled inside a segment of porcine small intestine. From the results, it is shown that the propulsive velocities of the tested capsules are in the range of 2.5 ~ 35 mm/s when rotating frequencies varying between 1 ~ 5 Hz are applied. Among all the capsules prepared for this study, the capsule No. 5, …


Spatial Dispersion In Three-Dimensional Drawn Magnetic Metamaterials, Alessandro Tuniz, Benjamin Pope, Anna Wang, Maryanne C. J Large, Shaghik Atakaramians, Seong-Sik Min, Elise M. Pogson, Roger A. Lewis, Avi Bendavid, Alexander Argyros, Simon C. Fleming, Boris T. Kuhlmey Jan 2012

Spatial Dispersion In Three-Dimensional Drawn Magnetic Metamaterials, Alessandro Tuniz, Benjamin Pope, Anna Wang, Maryanne C. J Large, Shaghik Atakaramians, Seong-Sik Min, Elise M. Pogson, Roger A. Lewis, Avi Bendavid, Alexander Argyros, Simon C. Fleming, Boris T. Kuhlmey

Faculty of Engineering - Papers (Archive)

We characterize spatial dispersion in longitudinally invariant drawn metamaterials with a magnetic response at terahertz frequencies, whereby a change in the angle of the incident field produces a shift in the resonant frequency. We present a simple analytical model to predict this shift. We also demonstrate that the spatial dispersion is eliminated by breaking the longitudinal invariance using laser ablation. The experimental results are in agreement with numerical simulations.


Fluidic Assembly At The Microscale: Progress And Prospects, Nathan B. Crane, Onursal Onen, Jose Carballo, Qi Ni, Rasim Guldiken Jan 2012

Fluidic Assembly At The Microscale: Progress And Prospects, Nathan B. Crane, Onursal Onen, Jose Carballo, Qi Ni, Rasim Guldiken

Faculty Publications

Assembly permits the integration of different materials and manufacturing processes to increase system functionality. It is an essential step in the fabrication of useful systems across size scales from buildings to molecules. However, at the microscale, traditional “grasp and release” assembly methods and chemically inspired self-assembly processes are less effective due to many scaling effects. Many methods have been developed for improving microscale assembly. Often these methods include fluidic forces or the use a fluidic medium in order to enhance their performance. This paper reviews basic assembly theory and modeling methods. Three basic assembly strategies (tool-directed, process-directed, and part-directed) are …