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Full-Text Articles in Physical Sciences and Mathematics
Kinetic Roughening Of Magnetic Flux Penetration In Mgb2 Thin Films, Andrea Lucarelli, Stephanie Hummert, Andrea Chaney, Gunter Lupke, Brian Moeckly, Yue Zhao, S X. Dou
Kinetic Roughening Of Magnetic Flux Penetration In Mgb2 Thin Films, Andrea Lucarelli, Stephanie Hummert, Andrea Chaney, Gunter Lupke, Brian Moeckly, Yue Zhao, S X. Dou
Australian Institute for Innovative Materials - Papers
Time-resolved magneto-optical studies are performed on MgB2 thin film samples grown by in situ pulsed laser deposition and in situ reactive deposition technique. The latter reveal dendritic avalanche-free flux penetration. The kinetic roughening of magnetic flux penetration is studied for applied ac current. Dynamic scaling laws determined for both static field and ac current are consistent with the directed percolation depinning model, placing the vortex dynamics in MgB2 in the same universality class as YBCO and Nb.
Silicon Oil: A Cheap Liquid Additive For Enhancing In-Field Critical Current Density In Mgb2, Xiaolin Wang, Zhenxiang Cheng, S X. Dou
Silicon Oil: A Cheap Liquid Additive For Enhancing In-Field Critical Current Density In Mgb2, Xiaolin Wang, Zhenxiang Cheng, S X. Dou
Australian Institute for Innovative Materials - Papers
In this work, the authors report on significant flux pinning enhancement in MgB2 that has been easily obtained using a liquid additive, silicon oil. MgB2 bulk samples with 0 up to 30 wt % silicon oil added were prepared by an in situ reaction. Results showed that the Si and C released from the decomposition of the silicon oil formed Mg2Si and substituted into B sites, respectively. Increasing the amount of the Si oil up to 15 wt % has resulted in the reduction of the lattice parameters, as well as Tc and R(300 K)/R(T …
Mgb2 For Application To Rf Cavities For Accelerators, Tsuyoshi Tajima, Alberto Canabal, Yue Zhao, Alexander Romanenko, Brian H. Moeckly, Christopher D. Nantista, Sami Tantawi, Larry Phillips, Yoshihisa Iwashita, Isidoro E. Campisi
Mgb2 For Application To Rf Cavities For Accelerators, Tsuyoshi Tajima, Alberto Canabal, Yue Zhao, Alexander Romanenko, Brian H. Moeckly, Christopher D. Nantista, Sami Tantawi, Larry Phillips, Yoshihisa Iwashita, Isidoro E. Campisi
Australian Institute for Innovative Materials - Papers
Magnesium diboride (MgB2) has a transition temperature (Tc) of ~40 K, i.e., about 4 times as high as that of niobium (Nb).We have been evaluating MgB2 as a candidate material for radio-frequency (RF) cavities for future particle accelerators. Studies in the last 3 years have shown that it could have about one order of magnitude less RF surface resistance (Rs) than Nb at 4 K. A power dependence test using a 6 GHz TE011 mode cavity has shown little power dependence up to ~12 mT (120 Oe), limited by available power, compared …
Improved Hydrogen Storage Of Libh4 Catalyzed Magnesium, J.F Mao, Z Wu, T.J Chen, B.C Weng, N.X Xu, T.S Huang, Zaiping Guo, Hua-Kun Liu, D.M Grant, Gavin S Walker, Xuebin Yu
Improved Hydrogen Storage Of Libh4 Catalyzed Magnesium, J.F Mao, Z Wu, T.J Chen, B.C Weng, N.X Xu, T.S Huang, Zaiping Guo, Hua-Kun Liu, D.M Grant, Gavin S Walker, Xuebin Yu
Australian Institute for Innovative Materials - Papers
The effect of LiBH4 on the hydrogen sorption performance of magnesium was investigated. It was found that the hydrogen storage properties of LiBH4/Mg mixtures exhibit a dramatic improvement as compared to plain magnesium powder. For example, at 250°C, a LiBH4/Mg (mass ratio 1:4) composite can absorb 6.7 wt % hydrogen in 60 min, while only less than 1 wt % hydrogen was absorbed by pure magnesium in the same period under similar conditions. The hydrogen desorption properties of the composite at 350°C were also improved significantly as compared to the plain …
Ferroelectric Properties Of Bi3.25sm0.75v0.02t2.98o12 Thin Film At Elevated Temperature, Zhenxiang Cheng, Xiaolin Wang, S X. Dou, Kiyoshi Ozawa, Hideo Kimura
Ferroelectric Properties Of Bi3.25sm0.75v0.02t2.98o12 Thin Film At Elevated Temperature, Zhenxiang Cheng, Xiaolin Wang, S X. Dou, Kiyoshi Ozawa, Hideo Kimura
Australian Institute for Innovative Materials - Papers
The ferroelectric behavior in terms of electrical polarization and fatigue and dielectric properties at elevated temperature of the ferroelectric Bi3.25Sm0.75V0.02T2.98O12 thin film fabricated by the pulsed laser deposition method were studied. Its switchable polarization increased at elevated temperature, and the coercive field decreased at the same time due to the strong domain depinning process at higher temperature. This film shows almost a polarization-fatigue-free character at room temperature, but the aggregation and diffusion of the thermally activated long-range oxygen vacancies caused strong domain pinning, and thus a poor fatigue resistance was observed …
Room Temperature Magnetic-Field Manipulation Of Electrical Polarization In Multiferroic Thin Film Composite Bifeo3/La2/3ca1/3mno3, Zhenxiang Cheng, Xiaolin Wang
Room Temperature Magnetic-Field Manipulation Of Electrical Polarization In Multiferroic Thin Film Composite Bifeo3/La2/3ca1/3mno3, Zhenxiang Cheng, Xiaolin Wang
Australian Institute for Innovative Materials - Papers
The electrical polarization in an epitaxially BiFeO3 film grown on La2/3Ca1/3MnO3/SrTiO3 is observed to be enhanced greatly by a magnetic field at room temperature. The simultaneous ferromagnetic order and ferroelectric polarization shown by the BiFeO3 film causes the strong coupling of the magnetic and ferroelectric domains in the BiFeO3 films. It was proposed that the activation energy for the electrical polarization domains switching is reduced by the application of a magnetic field. As a result, the electrical polarization that can be switched by an electrical field is increased by the …
Synthesis And Optimization Of Fluorine-Free Y And Cu Precursor Solution For Mod Processing Of Ybco Coated Conductor, Jaimoo Yoo, Young-Kuk Kim, Kookchae Chung, Jaewoong Ko, Xiaolin Wang, S X. Dou
Synthesis And Optimization Of Fluorine-Free Y And Cu Precursor Solution For Mod Processing Of Ybco Coated Conductor, Jaimoo Yoo, Young-Kuk Kim, Kookchae Chung, Jaewoong Ko, Xiaolin Wang, S X. Dou
Australian Institute for Innovative Materials - Papers
MOD solutions for YBCO coated conductors were synthesized with fluorine-free Y & Cu precursor. The fluorine content in the precursor solution was significantly reduced and a fast calcination profile was realized. A crack-free & thick precursor film was successfully obtained just after less than 2 hours of calcination in wet O2 atmosphere. Optimization of the precursor solution with Sm addition enables further improvement of thickness and uniformity of precursor films. The calcinated precursor film was successfully converted to dense and uniform YBCO film after annealing in wet Ar/O2 atmosphere. The measured critical current value was about 273 A/cm-w …
Single-Crystal Growth And Anisotropic Magnetic Properties Of Nonstoichiometric Three-Layer Sodium Cobalt Oxides, Dapeng Chen, Xiaolin Wang, C T Lin, S X. Dou
Single-Crystal Growth And Anisotropic Magnetic Properties Of Nonstoichiometric Three-Layer Sodium Cobalt Oxides, Dapeng Chen, Xiaolin Wang, C T Lin, S X. Dou
Australian Institute for Innovative Materials - Papers
Large single crystals of α-NaxCoO2 (x=0.91, 0.92, and 0.93) have been successfully fabricated by using the traveling solvent floating zone method. Details on the crystal growth are discussed. The crystal structures were characterized using powder x-ray diffraction and Rietveld refinement. The magnetic susceptibility measurements show that the magnetic properties depend strongly on x. The compound was found to be antiferromagnetic at TN ≈ 20 K for x=0.91 and x=0.92, and paramagnetic for x=0.93. The in-plane and out-of-plane anisotropies were observed for the x=0.91 crystals. In addition, the derived anisotropic g-factor ratios (gab /gc) …
Bi-2212 Based Anode Materials For Li-Ion Batteries, Matthew Lindsay, Hua-Kun Liu
Bi-2212 Based Anode Materials For Li-Ion Batteries, Matthew Lindsay, Hua-Kun Liu
Australian Institute for Innovative Materials - Papers
A number of studies have previously examined the insertion of lithium into superconductor Bi2Sr2CaCu2O8+δ(Bi-2212) materials. A maximum lithium uptake of two moles of lithium per mole of Bi-2212 was reported amongst these studies which corresponds to a capacity of 60 mAh/g. Two Bi-2212 materials are examined here an undoped Bi2Sr2CaCu2O8+δ and doped Bi2Sr2Ca0.3Y0.7Cu2O8 material. Both materials exhibitied a capacity of over 60 mAh/g in both the as produced stated and whn subjected to further …
Elliptical Hole Pockets In The Fermi Surfaces Of Unhydrated And Hydrated Sodium Cobalt Oxides, J Laverock, S B. Dugdale, J A. Duffy, J Wooldridge, G Balakrishnan, M R. Lees, G.-Q Zheng, Dapeng Chen, C T. Lin, Y Sakurai
Elliptical Hole Pockets In The Fermi Surfaces Of Unhydrated And Hydrated Sodium Cobalt Oxides, J Laverock, S B. Dugdale, J A. Duffy, J Wooldridge, G Balakrishnan, M R. Lees, G.-Q Zheng, Dapeng Chen, C T. Lin, Y Sakurai
Australian Institute for Innovative Materials - Papers
The surprise discovery of superconductivity below 5 K in sodium cobalt oxides when hydrated with water has caught the attention of experimentalists and theorists alike. Most explanations for its occurence have focused heavily on the properties of some small elliptically shaped pockets predicted to be the electronically dominant Fermi surface sheet, but direct attempts to look for them have instead cast serious doubts over their existence. Here we present evidence that these pockets do indeed exist, based on bulk measurements of the electron momentum distribution in unhydrated and hydrated sodium cobalt oxides using the technique of x-ray Compton scattering.
Soft-Structured Sensors And Connectors By Inkjet Printing, Amit Sawhney, Animesh Agrawal, Te-Chen Lo, Prabir K. Patra, Chi H. Chen, Paul Calvert
Soft-Structured Sensors And Connectors By Inkjet Printing, Amit Sawhney, Animesh Agrawal, Te-Chen Lo, Prabir K. Patra, Chi H. Chen, Paul Calvert
Australian Institute for Innovative Materials - Papers
The properties of conducting polymers deposited onto textiles were studied over 10 years ago by workers at Los Alamos and Milliken who also tested these materials as gas sensors [1-3]. More recently, workers at Wollongong have demonstrated that elastic textiles impregnated with conducting polymers, by in situ chemical polymerization, can act as strain sensors that can be used to track the motion of human joints [4]. A similar approach can be used to make pressure-sensing foams [5]. Others have studied the strain sensing mechanism in more detail and have shown that two effects are important. In one case, cracking of …
Effective Gel For Gold Nanoparticle Formation, Support And Metal Oxide Templating, Xingdong Wang, Caroline E. Egan, Meifang Zhou, Kathryn Prince, David Rg Mitchell, Rachel A. Caruso
Effective Gel For Gold Nanoparticle Formation, Support And Metal Oxide Templating, Xingdong Wang, Caroline E. Egan, Meifang Zhou, Kathryn Prince, David Rg Mitchell, Rachel A. Caruso
Australian Institute for Innovative Materials - Papers
Gold nanoparticles were synthesized using agarose as a reducing agent, which gelled to support the gold nanoparticles, then readily functioned as a template to produce a porous, evenly-distributed Au/TiO2 nano-hybrid.
5-Methoxy-2-Methyl-4-Nitro-1-Phenyl-1h-Imidazole, Pawel Wagner, Maciej Kubicki
5-Methoxy-2-Methyl-4-Nitro-1-Phenyl-1h-Imidazole, Pawel Wagner, Maciej Kubicki
Australian Institute for Innovative Materials - Papers
The title compound, C11H11N3O3, contains two planar fragments, viz. the imidazole and phenyl rings. These rings are significantly twisted with respect one to another, with a dihedral angle of 63.99 (8)°. The nitro group is almost coplanar with the imidazole plane, while the methoxy group is almost perpendicular to it [the C—C—O—C torsion angle is 65.1 (4)°]. In spite of this, there is a short C(methoxy)—H...O(nitro) contact that might be regarded as an intramolecular hydrogen bond. Weak intermolecular C—H...N(imidazole) and C—H...O(nitro) hydrogen bonds create quite a complicated network that consists of …
2-Methyl-4-Nitro-1-(3-Pyridyl)-1h-Imidazole, Maciej Kubicki, Pawel Wagner
2-Methyl-4-Nitro-1-(3-Pyridyl)-1h-Imidazole, Maciej Kubicki, Pawel Wagner
Australian Institute for Innovative Materials - Papers
The imidazole and pyridine rings in the title compound, C9H8N4O4, are twisted with respect to one another, with a dihedral angle of 48.30 (4)°. The nitro group is almost coplanar with the imidazole plane. The crystal packing involves some weak C—H...N and C—H...O hydrogen bonds, of which the strongest, between the imidazole CH group and a nitro O atom [H...O 2.396 (15) Å], forms a centrosymmetric dimer.
Ring Transformations In The Reactions Of 1,4-Dinitropyrazole With N-Nucleophiles, Rafal Jedrysiak, Marcin Sawicki, Pawel Wagner, Jerzy Suwinski
Ring Transformations In The Reactions Of 1,4-Dinitropyrazole With N-Nucleophiles, Rafal Jedrysiak, Marcin Sawicki, Pawel Wagner, Jerzy Suwinski
Australian Institute for Innovative Materials - Papers
The reactions of 1,4-dinitropyrazole with primary amines, hydrazines, hydroxylamine and amidines were studied. 1,4-Dinitropyrazole in these reactions served as the synthetic equiv. of nitromalonaldehyde. The reaction of dinitropyrazole with primary arylhydrazines proved to be a convenient approach to the synthesis of 1-aryl-4-nitropyrazoles.
Josephson-Vortex Flow Resistance In Bi2sr2ca2cu3oy Single Crystals And Its Possible Application In The Manipulation Of Spin And Charge Textures In Diluted Magnetic Semiconductors, Xiaolin Wang, C T Lin, B Liang, S Yu, S Ooi, K Hirata, S Y Ding, Dongqi Shi, S X. Dou, Zhi W. Lin, Jian G. Zhu
Josephson-Vortex Flow Resistance In Bi2sr2ca2cu3oy Single Crystals And Its Possible Application In The Manipulation Of Spin And Charge Textures In Diluted Magnetic Semiconductors, Xiaolin Wang, C T Lin, B Liang, S Yu, S Ooi, K Hirata, S Y Ding, Dongqi Shi, S X. Dou, Zhi W. Lin, Jian G. Zhu
Australian Institute for Innovative Materials - Papers
In this work, the flow of the Josephson vortices (JVs) has been studied for the highly anisotropic Bi2Sr2Ca2Cu3Oy (Bi2223) single crystals. A giant flow of JVs or giant positive magnetoresistance (MR) of over 500%-2000% was obtained in fields of 0.1-5 T and remained almost constant over a wide temperature range from 110 down to 4 K, in contrast to superconducting vortices (SVs), which only produced MR in the vicinity of Tc. The flow of the JVs is expected to be much faster than that of SVs. It is proposed …
Apparent Negative Mobility Of Vortex Matter Due To Inhomogeneous Pinning, X B Xu, H Fangohr, Shichao Ding, M Gu, T.B Tang, Z Han, Dongqi Shi, S X. Dou
Apparent Negative Mobility Of Vortex Matter Due To Inhomogeneous Pinning, X B Xu, H Fangohr, Shichao Ding, M Gu, T.B Tang, Z Han, Dongqi Shi, S X. Dou
Australian Institute for Innovative Materials - Papers
We investigate the transport of vortices in superconductors with inhomogeneous pinning under a driving force. The inhomogeneity of pinning is simplified as strong-weak pinning regions. It is demonstrated that the interactions between the vortices captured by strong pinning potentials and the vortices in the weak pinning region cause absolute negative motion (ANM) of vortices: The vortices which are climbing toward the high barriers induced by the strong pinning with the help of driving force move toward the opposite direction of the force and back to their equilibrium positions in the weak pinning region as the force decreases or is withdrawn. …
Band Structures, Magnetic Properties, And Enhanced Magnetoresistance In The High Pressure Phase Of Gd And Y Doped Two-Dimensional Perovskite Sr2coo4 Compounds, Xiaolin Wang, E Takayama-Muromachi, S X. Dou, Zhenxiang Cheng
Band Structures, Magnetic Properties, And Enhanced Magnetoresistance In The High Pressure Phase Of Gd And Y Doped Two-Dimensional Perovskite Sr2coo4 Compounds, Xiaolin Wang, E Takayama-Muromachi, S X. Dou, Zhenxiang Cheng
Australian Institute for Innovative Materials - Papers
The authors present their studies on the band structures and on the magnetic and magnetotransport properties of the high pressure phase of Sr2-xRExCoO4 [rare earth (RE)=Gd and Y, x=0.1-0.5] compounds which were synthesized by a high pressure and high temperature technique. The authors found that as x increases, the magnetoresistance {(PH-P0)/p0} increases up to -17% at 5 K and 7 T, which is 2.5 times higher than that for undoped Sr2CoO4, although the ferromagnetic transition drops from 255 to 200 K for the Gd doping with x=0.3. …
Manganese Dioxide Cathode In The Presence Of Tis2 As Additive On An Aqueous Lithium Secondary Cell, Manickam Minakshi, Pritam Singh, David Rg Mitchell
Manganese Dioxide Cathode In The Presence Of Tis2 As Additive On An Aqueous Lithium Secondary Cell, Manickam Minakshi, Pritam Singh, David Rg Mitchell
Australian Institute for Innovative Materials - Papers
Intercalation of lithium into the vacant sites of a host compound can be achieved electrochemically using nonaqueous electrolytes. The use of aqueous electrolyte is less common because of the reactivity of many lithium intercalation compounds with water. Here, we propose that lithium could be intercalated into the manganese dioxide cathode in a battery using saturated lithium hydroxide as the electrolyte. The positive electrode reaction at MnO2 in this medium is shown to be lithium insertion rather than the usual protonation, and acceptable rechargeability is observed. Using X-ray photoelectron spectroscopy and scanning electron microscope analysis on the discharged cathode material we …
Crystal Packing Of Two 5-Substituted 2-Methyl-4-Nitro-1h-Imidazoles, Pawel Wagner, Krzysztof Swierczek, Maciej Kubicki
Crystal Packing Of Two 5-Substituted 2-Methyl-4-Nitro-1h-Imidazoles, Pawel Wagner, Krzysztof Swierczek, Maciej Kubicki
Australian Institute for Innovative Materials - Papers
Infinite chains connected by N-H...N hydrogen bonding form the primary packing motif in two closely related 4-nitroimidazole derivatives, viz. 5-bromo-2-methyl-4-nitro-1H-imidazole, C4H4BrN3O2, (I), and 2-methyl-4-nitro-1H-imidazole-5-carbonitrile, C5H4N4O2, (II). These chains are almost identical, even though in (II) there are two symmetry-independent molecules in the asymmetric unit. The differences appear in the interactions between the chains; in (I), there are strong C-Br...O halogen bonds, which connect the chains into a two-dimensional grid, while in (II), the cyano group does not participate in specific interactions and the chains are only loosely connected into a three-dimensional structure.
Two Different Modes Of Halogen Bonding In Two 4-Nitroimidazole Derivatives, Maciej Kubicki, Pawel Wagner
Two Different Modes Of Halogen Bonding In Two 4-Nitroimidazole Derivatives, Maciej Kubicki, Pawel Wagner
Australian Institute for Innovative Materials - Papers
In the crystal structures of the two imidazole derivatives 5-chloro-1,2-dimethyl-4-nitro-1H-imidazole, C5H6ClN3O2, (I), and 2-chloro-1-methyl-4-nitro-1H-imidazole, C4H4ClN3O2, (II), C—Cl...O halogen bonds are the principal specific interactions responsible for the crystal packing. Two different halogen-bond modes are observed: in (I), there is one very short and directional C—Cl...O contact [Cl...O = 2.899 (1) Å], while in (II), the C—Cl group approaches two different O atoms from two different molecules, and the contacts are longer [3.285 (2) and 3.498 (2) Å] and less directional. …
2-Methyl-4-Nitro-1-(4-Nitrophenyl)-1h-Imidazole, Pawel Wagner, Maciej Kubicki
2-Methyl-4-Nitro-1-(4-Nitrophenyl)-1h-Imidazole, Pawel Wagner, Maciej Kubicki
Australian Institute for Innovative Materials - Papers
In the title compound, C10H8N4O4, two planar fragments, viz. the imidazole and nitrophenyl rings, are tilted at a dihedral of 57.89 (7)°. The nitro groups are twisted with respect to the neighbouring ring planes; the dihedral angle is 7.0 (3)° for imidazole and 9.68 (8)° for benzene. The crystal structure consists of centrosymmetric dimers generated by C—H...O hydrogen bonds, which are connected by C—H...N hydrogen bonds into rows along the [001] direction. The neighbouring rows are connected via C—H...O interactions into a two-dimensional network in the bc plane.
2-Methoxy-1-Methyl-4-Nitro-1h-Imidazole, Maciej Kubicki, Pawel Wagner
2-Methoxy-1-Methyl-4-Nitro-1h-Imidazole, Maciej Kubicki, Pawel Wagner
Australian Institute for Innovative Materials - Papers
The molecule of the title compound, C5H7N3O3, is approximately planar. The maximum deviation from the least-squares plane calculated for all non-H atoms is 0.054 (2) Å. The dihedral angles between the mean plane of the imidazole ring [planar within 0.0017 (6) Å] and the planes of the nitro and methoxy groups are 2.9 (1) and 1.2 (1)°, respectively. The molecules are held together by weak C—H...N and C—H...O interactions and by van der Waals forces.
Direct Imaging Of Individual Intrinsic Hydration Layers On Lipid Bilayers With Angstrom Resolution, Takeshi Fukuma, Michael J. Higgins, Suzanne P. Jarvis
Direct Imaging Of Individual Intrinsic Hydration Layers On Lipid Bilayers With Angstrom Resolution, Takeshi Fukuma, Michael J. Higgins, Suzanne P. Jarvis
Australian Institute for Innovative Materials - Papers
The interactions between water and biological molecules have the potential to influence the structure, dynamics, and function of biological systems, hence the importance of revealing the nature of these interactions in relation to the local biochemical environment. We have investigated the structuring of water at the interface of supported dipalmitoylphosphatidylcholine bilayers in the gel phase in phosphate buffer solution using frequency modulation atomic force microscopy (FM-AFM). We present experimental results supporting the existence of intrinsic (i.e., surface-induced) hydration layers adjacent to the bilayer. The force versus distance curves measured between the bilayer and the AFM tip show oscillatory force profiles …