Zobrazeno 1 - 10
of 1 499
pro vyhledávání: '"LIU, H. K."'
Sample size dependent critical current density has been observed in magnesium diboride superconductors. At high fields, larger samples provide higher critical current densities, while at low fields, larger samples give rise to lower critical current
Externí odkaz:
http://arxiv.org/abs/cond-mat/0305201
Publikováno v:
Physica C 385 (2003) 461-465
Polycrystalline MgB2 samples with 10 wt % silicon powder addition were prepared by an in-situ reaction process. Two different Si powders, one with coarse (44 mm) and the other with nano-size (<100 nm) particles were used for making samples. The phase
Externí odkaz:
http://arxiv.org/abs/cond-mat/0208349
Autor:
Dou, S. X., Soltanian, S., Horvat, J., Wang, X. L., Munroe, P., Zhou, S. H., Ionescu, M., Liu, H. K., Tomsic, M.
Publikováno v:
Appl. Phys. Lett. 81, 3419 (2002)
Doping of MgB2 by nano-SiC and its potential for improvement of flux pinning was studied for MgB2-x(SiC)x/2 with x = 0, 0.2 and 0.3 and a 10wt% nano-SiC doped MgB2 samples. Co-substitution of B by Si and C counterbalanced the effects of single-elemen
Externí odkaz:
http://arxiv.org/abs/cond-mat/0207223
Autor:
Dou, S. X., Pan, A. V., Zhou, S., Ionescu, M., Wang, X. L., Horvat, J., Liu, H. K., Munroe, P. R.
Publikováno v:
J. Appl. Phys. 94, 1850-1856 (2003)
We investigated the effect of SiC nano-particle doping on the crystal lattice structure, critical temperature T_c, critical current density J_c, and flux pinning in MgB_2 superconductor. A series of MgB_{2-x}(SiC)_{x/2} samples with x = 0 to 1.0 were
Externí odkaz:
http://arxiv.org/abs/cond-mat/0207093
Publikováno v:
Supercond. Sci. Technol. 15, pp.1587-1591 (2002)
By doping MgB_2 superconductor with SiC nano-particles, we have successfully introduced pinning sites directly into the crystal lattice of MgB_2 grains (intra-grain pinning). It became possible due to the combination of counter-balanced Si and C co-s
Externí odkaz:
http://arxiv.org/abs/cond-mat/0206444
Publikováno v:
Physica C 382 (2002) 187-193
The powder in tube method has been used to fabricate Ag and Cu clad MgB2 wires using an in-situ reaction method. The effects of short time sintering on the critical current densities of Ag and Cu clad MgB2 wires were studied. All the samples were exa
Externí odkaz:
http://arxiv.org/abs/cond-mat/0201261
The magnetic levitation forces of a superconducting disk (SC) levitated by a cylindrical permanent magnet (PM) have been calculated from first principles for superconductors with finite thickness. The current $j(\rho,z)$ and field $B(\rho,z)$ profile
Externí odkaz:
http://arxiv.org/abs/cond-mat/0111316
The magnetic field dependent critical current density $j_c(B)$ of a MgB$_2$ bulk sample has been obtained by means of magnetization hysteresis measurements. The $j_c(B)$ curves at different temperatures demonstrate a crossover from single vortex pinn
Externí odkaz:
http://arxiv.org/abs/cond-mat/0108172
Publikováno v:
Physica C 361 (2001) 149
In this paper we have investigated the effects of sintering time and temperature on the formation and critical current densities of Fe-clad MgB2 wires. MgB2 wires were fabricated using the powder-in-tube process and sintered for different periods of
Externí odkaz:
http://arxiv.org/abs/cond-mat/0106148
Autor:
Soltanian, S., Wang, X. L., Kusevic, I., Babic, E., Li, A. H., Liu, H. K., Collings, E. W., Dou, S. X.
Fe-clad MgB2 long tapes have been fabricated using a powder-in-tube technique. An Mg + 2B mixture was used as the central conductor core and reacted in-situ to form MgB2. The tapes were sintered in pure Ar at 800 ^(o) C for 1 h at ambient pressure. S
Externí odkaz:
http://arxiv.org/abs/cond-mat/0105152