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Articles 1 - 9 of 9
Full-Text Articles in Physical Sciences and Mathematics
Electronic Properties Of Carbon Nanotubes With Distinct Bond Lengths, J E. Bunder, James M. Hill
Electronic Properties Of Carbon Nanotubes With Distinct Bond Lengths, J E. Bunder, James M. Hill
Faculty of Informatics - Papers (Archive)
In band structure calculations commonly used to derive the electronic properties of carbon nanotubes it is generally assumed that all bond lengths are equal. However, hexagonal carbon lattices are often irregular and may contain as many as three distinct bond lengths. A regular $(n,m)$ carbon nanotube will be metallic if p=(n-m)/3 for integer p. Here we analytically derive the generalized condition for metallic irregular carbon nanotubes. This condition is particularly relevant to small radius nanotubes and nanotubes experiencing small applied strains.
Magnetic Properties Of Ho2fe17-Xmnx - Influence Of Mn Substitution, Jianli Wang, Stewart J. Campbell, A J Studer, S J. Kennedy, Rong Zeng
Magnetic Properties Of Ho2fe17-Xmnx - Influence Of Mn Substitution, Jianli Wang, Stewart J. Campbell, A J Studer, S J. Kennedy, Rong Zeng
Australian Institute for Innovative Materials - Papers
The structural and magnetic properties of Ho2Fe17−xMnx (x=0-5) have been investigated by x-ray diffraction, Mössbauer spectroscopy and DC magnetization measurements (0-5 T) over the temperature range 4.5-350 K. Similar to other ferrimagnetic R2Fe17-xMnx systems, the unit cell volume generally increases with Mn content other than for low Mn values where a slight maximum is detected around x ∼ 0.5. The nature of the magnetic phase transitions around TC is shown by Arrot plot analysis to be second order for all samples. The Curie temperature remains essentially unchanged …
The Mechanical And The Electrical Properties Of Conducting Polypyrrole Fibers, Javad Foroughi, Shaban R. Ghorbani, Germanas Peleckis, Geoffrey M. Spinks, Gordon G. Wallace, Xiaolin Wang, S X. Dou
The Mechanical And The Electrical Properties Of Conducting Polypyrrole Fibers, Javad Foroughi, Shaban R. Ghorbani, Germanas Peleckis, Geoffrey M. Spinks, Gordon G. Wallace, Xiaolin Wang, S X. Dou
Australian Institute for Innovative Materials - Papers
The mechanical and the electrical properties of polypyrrole (PPy) fibers and electrochemically deposited PPy films were studied. It was found that the PPy fibers showed a significantly higher strength than the PPy films due to better orientation of the molecular structure. The electrochemically prepared PPy films had a higher electrical conductivity than that of the fibers at high temperature. At low temperature, the PPy fibers showed the higher conductivity. The conductivity results were analyzed in the frame of the three-dimensional variable range hopping model. The results showed that at room temperature the average hopping distance for the fibers was about …
Structure, Magnetic, And Thermal Properties Of Nd1-Xlaxcro3 (0 ≤ X ≤ 1.0), Yi Du, Zhenxiang Cheng, Xiaolin Wang, S X. Dou
Structure, Magnetic, And Thermal Properties Of Nd1-Xlaxcro3 (0 ≤ X ≤ 1.0), Yi Du, Zhenxiang Cheng, Xiaolin Wang, S X. Dou
Australian Institute for Innovative Materials - Papers
Perovskite-type Nd1−xLaxCrO3(0 ≤ x ≤1.0) polycrystalline samples were synthesized using solid state reaction. Structural studies indicate that the lattice parameters, metal–oxygen bond lengths, and angles of Nd1−xLaxCrO3 strongly depend on the La content. Two magnetic transition temperatures, Cr3+ antiferromagnetic ordering temperature (TN) and the spin reorientation phase transition temperature (TSRPT), have been observed in the M-T curves. The increase in TN and decrease in TSRPT with increasing x value can be explained by the change in the magnetic interactions due to La …
Magnetic Properties Of La Doped Bi2femno6 Ceramic And Film, Hongyang Zhao, Hideo Kimura, Zhenxiang Cheng, Xiaolin Wang, Kiyoshi Ozawa, Takashi Nishida
Magnetic Properties Of La Doped Bi2femno6 Ceramic And Film, Hongyang Zhao, Hideo Kimura, Zhenxiang Cheng, Xiaolin Wang, Kiyoshi Ozawa, Takashi Nishida
Australian Institute for Innovative Materials - Papers
We present a comprehensive study of the magnetic properties for La doped Bi2FeMnO6 (LBFM) ceramic and film which was first deposited on (100) SrTiO3 substrate by pulsed laser deposition method. The LBFM film is antiferromagnetic or weak ferrimagnetic at room temperature and it shows clear magnetic anisotropy. But it is not sure whether the spin-glass behavior is present in LBFM film because of the influence from substrate. Compared to the film, LBFM ceramic shows different magnetic properties. It has a lower TN and all the observations indicate that LBFM ceramic shows spin-glass behavior.
Synthesis And Physical Properties Of Fese1/2 Te1/2 Superconductor, V P. Awana, Anand Pal, Arpita Vajpayee, Monika Mudgel, H Kishan, Mushahid Husain, Rong Zeng, S Yu, Y F. Guo, Y.G Shi, K Yamaura, E Takayama-Muromachi
Synthesis And Physical Properties Of Fese1/2 Te1/2 Superconductor, V P. Awana, Anand Pal, Arpita Vajpayee, Monika Mudgel, H Kishan, Mushahid Husain, Rong Zeng, S Yu, Y F. Guo, Y.G Shi, K Yamaura, E Takayama-Muromachi
Australian Institute for Innovative Materials - Papers
One of the most important properties of very recently reported FeSe based superconductors is the robustness of their superconductivity under applied magnetic field. The synthesis and control of superconductivity in FeSe based compounds is rather a difficult task. Synthesis and physical property characterization for optimized superconductivity of FeSe1/2Te1/2 at 13 K is reported here. The compound crystallized in a tetragonal structure with lattice parameters a=3.8015(2) and c =6.0280(4) Å. Magnetization measurements indicated bulk superconductivity with lower critical field (Hc1) of around 180 Oe. By applying Ginzburg–Landau theory, the Hc2(0) value is estimated to …
Lanthanum Doped Multiferroic Dyfeo3: Structural And Magnetic Properties, Yi Du, Zhenxiang Cheng, Xiaolin Wang, S X. Dou
Lanthanum Doped Multiferroic Dyfeo3: Structural And Magnetic Properties, Yi Du, Zhenxiang Cheng, Xiaolin Wang, S X. Dou
Australian Institute for Innovative Materials - Papers
Lanthanum doped multiferroic DyFeO3 was synthesized by solid state reaction. X-ray diffraction and refinement show that the lattice parameters of Dy1−xLaxFeO3 increase linearly with the La content. Raman spectroscopy reveals that the short-range force constant in Dy1−xLaxFeO3 is decreased by La3+ ion substitution. The spin reorientation phase transition temperature (TSRPT) is observed to decrease along with the doping level. The antiferromagnetic ordering temperature TN of Fe3+ ions is depressed with increasing doping level. Both decreasing TSRPT and decreasing TN indicate that Fe–Dy and Fe–Fe …
Magnetic Properties Of Bi2femno6: A Multiferroic Material With Double-Perovskite Structure, Yi Du, Zhenxiang Cheng, S X. Dou, Xiaolin Wang, Hua Zhao, Hideo Kimura
Magnetic Properties Of Bi2femno6: A Multiferroic Material With Double-Perovskite Structure, Yi Du, Zhenxiang Cheng, S X. Dou, Xiaolin Wang, Hua Zhao, Hideo Kimura
Australian Institute for Innovative Materials - Papers
Single phase Bi2FeMnO6 was synthesized on Si substrates by an electrospray method. Three peaks were observed in the temperature dependence of magnetization curve, which is attributed to the inhomogeneous distribution of Fe3+ and Mn3+. The observed magnetic peaks at 150 K, 260 K, and 440 K correspond to orderings of the ferrimagnetic Fe–O–Mn, and antiferromagnetic Mn–O–Mn and Fe–O–Fe, respectively. Heat capacity measurements were carried out to confirm these magnetic transitions. The Debye temperature of Bi2FeMnO6 is 339 K, calculated from Debye–Einstein fitting.
Superconducting Properties Of Carbonaceous Chemical Doped Mgb2, Wenxian Li, S X. Dou
Superconducting Properties Of Carbonaceous Chemical Doped Mgb2, Wenxian Li, S X. Dou
Australian Institute for Innovative Materials - Papers
The discovery of superconductivity in magnesium diboride (MgB2: 39 K, in January 2001) (Nagamatsu et al., 2001) has generated enormous interest and excitement in the superconductivity community and the world in general, but especially among researchers into superconductivity in non-oxide and boron related compounds.