Results 161 to 170 of about 6,016 (192)

Effects of copper doping in MgB2 superconductor

Solid State Communications, 2002
Starting from CuB24, Mg1-xCuxB2 compounds with x ranging from 0.003 to 0.03 were synthesised. The lattice parameters of the AlB2-type phase systematically changes with increasing starting CuB24 fraction, indicating that a partial Cu substitution takes place by using this method. With increasing the copper content, Tc decreases (dTc/dx = -18 K for x > 0.
Tampieri A., Celotti G., Sprio S., Rinaldi D., Barucca G., Caciuffo R.   +5 more
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Microwave absorption studies of MgB2 superconductor

Pramana, 2002
Microwave absorption studies have been carried out on MgB2 superconductor using a standard X-band EPR spectrometer. The modulated low-field microwave absorption signals recorded for polycrystalline (grain size ∼ 10 µm) samples suggested the absence of weak-link character.
MK Bhide, RM Kadam, MD Sastry, Ajay Singh, Shashwati Sen, Manmeet Kaur, DK Aswal, SK Gupta, VC Sahni   +8 more
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Synthesis and characterization of MgB2 superconductor

Physica C: Superconductivity, 2001
Abstract Starting with Mg in two different forms, namely, powder and flakes, and B as powder, MgB 2 superconductor has been synthesized using solid-state sintering method under atmospheric pressure of argon. The grain growth of MgB 2 was greatly enhanced when magnesium flakes were employed. MgB 2 grains having a size of up to 3×2×1 mm 3
D.K Aswal, Shashwati Sen, Ajay Singh, T.V Chandrasekhar Rao, J.C Vyas, L.C Gupta, S.K Gupta, V.C Sahni   +7 more
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Flux motion in new superconductor MgB2

Physica C: Superconductivity, 2003
Abstract Flux motion and its influence on the properties of the new discovered superconductor MgB 2 was studied by electric transport resistance as well as by ac susceptibility measurements. Different bias current I was applied perpendicular and parallel to applied dc field B d up to 7 T.
H Luo, Y Liu, X Leng, Z.H Wang, S.Y Ding, X.L Wang, S.X Dou   +6 more
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Model spectral function for MgB2 superconductor

Physics Letters A, 2001
The Eliashberg spectral density function is constructed for the newly discovered MgB2. The model function shows spreading spectra that are nearly similar to those from first principles calculation. It provides a good description of the physical properties of MgB2. The results of the analysis are consistent with a phonon-mediated superconductivity, with
A.K.M.A. Islam, F.N. Islam, M.N. Islam
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Filamentary MgB2 Superconductors with Titanium Barriers

Journal of Superconductivity and Novel Magnetism, 2012
Ti diffusion barrier has been applied for several Cu stabilized MgB2 wires. Pure Ti is well formable metal allowing formation of thin barrier layers which are not reacting with MgB2. Instead of, Ti is able to purify MgB2 filaments by absorbing some impurities during the final heat treatment. Ti has comparable coefficient of thermal expansion with MgB2,
P. Kováč, I. Hušek, T. Melišek, L. Kopera, M. Polák   +4 more
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ESR studies on high-Tc superconductor MgB2

Physica C: Superconductivity, 2003
MgB2, a high-T-c superconductor, has been studied by electron spin resonance (ESR) techniques at the temperature range of 7-300 K.
Y. Köseoģlu, B. Aktaş, F. Yildiz, D.K. Kim, M. Toprak, M. Muhammed   +5 more
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Heterostructures of Bi-4334 and MgB2 superconductors

AIP Conference Proceedings, 2016
We report the studies on hetero structures of Bi-4334 and MgB2 superconductors. The two superconductors were arranged in the form of bulk multilayers using hydraulic pressure system. X-ray diffraction pattern and dc magnetization studies confirm the presence of both superconducting phases in this try-layer hetero structured sample.
M. Padmavathi, R. Singh
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Studies of transport properties of MgB2 superconductor

Physica C: Superconductivity, 2003
Abstract We present the results of electrical resistivity, thermoelectric power and thermal conductivity on polycrystalline MgB 2 samples. From the analysis of the results we find the Fermi energy E F =0.8 eV and the electron–phonon coupling constant, λ tr , estimated from transport properties, lies in the range 1.25–2.25.
A. Poddar, B. Bandyopadhyay, P. Mandal, D. Bhattacharya, P. Choudhury, U. Sinha, B. Ghosh   +6 more
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Al addition effect of bulk MgB2 superconductor

Physica C: Superconductivity and its Applications, 2007
Abstract The properties of transport and magnetization have been investigated for bulk MgB 2 Al x superconductor with Al addition ( x  = 0, 0.5, 1 wt%). MgB 2 bulk samples sintered at different temperatures at 650–740 °C were prepared in the undoped state.
K. Shinohara, H. Ikeda, R. Yoshizaki
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