Effect of B2O3 addition on the formation and properties of Tl-2212 and Tl-2223 superconductors

Cavdar, S
Aksu, E
Koralay, H
Ozkan, H
Hasanlı, Nızamı
Ercan, I
We have studied the effect of B2O3 addition on the formation and properties of the Tl-based superconductors. Polycrystalline Tl-2212 and Tl-2223 samples were synthesized by adding B2O3 to the chemicals at the first and at the second stage of two stages sintering processes (3+1 h) at 860 C. X-ray powder diffraction patterns, resistance versus temperature behaviours and the micrographs of the B2O3 free and B2O3 added samples have been analysed. The compositions and the critical temperatures of the samples indicate that about 1.0 weight percent B2O3 added at the first stage of sintering stabilize the Tl-2212 phase and at the second stage promote the formation of the Tl-2223 phase. For both of the phases, the a-lattice parameter remains the same, but the c-parameter slightly decreases with B2O3 additions. Few small peaks due to the impurity phases appear in the diffraction patterns but none due to B2O3 or any other phase involving B atoms. We suggest that, with their small size B atoms may partially substitute Cu atoms and disperse at interstitial positions and grain boundaries. (C) 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Effect of Li addition on the properties of Bi-based superconductors
Ogun, SE; Ozkan, H; Hasanlı, Nızamı (Institute of Electrical and Electronics Engineers (IEEE), 2003-06-01)
The effect of Li addition on the formation and properties of Pb containing Bi-based superconductors has been studied. Three successive thermal sintering cycles have been applied to the oxides adjusted for the nominal composition, Bi1.6Pb0.4Sr2CaCu2O8+d. Eight different samples having Li2CO3 from 0.0 up to 3.0 weight% have been synthesized, X-ray diffraction patterns, resistivity-temperature behaviors and differential thermal analysis of the samples have been examined. Li2CO3 addition at 650degreesC decrease...
OZKAN, H; ALBISS, BA; HAMDAN, N; MENARD, A (Springer Science and Business Media LLC, 1994-12-01)
The effect of gamma-irradiation and silver doping on the properties of YBCO superconductors has been studied by electrical resistance measurements and x-ray diffraction techniques. The zero-resistance superconducting transition temperature of (YBCO)(1-x)Ag-x systematically increase by about 2 K with an increase of Ag content up to x = 0.04. Further increase in Ag content decreases the transition temperature. The normal-state resistance decreases up to a factor of 3.4 with an increase of Ag content. No signi...
lambda-transition of NH4Cl and ND4Cl at high pressures
Yurtseven, Hasan Hamit; Sen, S. (Wiley, 2007-07-01)
We predict in this study using the mean-field theory, the phase-line equation from the free energy expanded in terms of the order parameters of solid II and III phases of NH4Cl and ND4Cl close to the X-phase transitions at high pressures. Using the temperature and pressure dependence of the coefficients given in the phase-line equation, it is shown that the experimentally observed T-P phase diagram for the solid II-solid III transition, can be predicted from the mean field model studied here for both crysta...
Effects of screening on the two-dimensional electron transport properties in modulation doped heterostructures
Sen, O; Beşikci, Cengiz; Tanatar, B (Elsevier BV, 1998-06-01)
The effects of screening on the polar optical phonon scattering rates and on the transport properties of the two-dimensional electron gas in AlGaAs/GaAs modulation doped heterostructures have been investigated through Monte Carlo simulations incorporating the three valleys of the conduction band, size quantization in the Gamma valley and the lowest three subbands in the quantum-well. At typical sheet densities observed in modulation doped field-effect transistors, screening considerably affects the electron...
Mehrabov, Amdulla; MATYSINA, ZA (Wiley, 1989-12-01)
For the first time theoretical (in terms of the classical theory of ordering) and experimental (with the adiabatic calorimeter method) investigations are made of the effect of a third component impurity C on the heat capacity of A3B‐type ordered alloys with FCC structure. The effect of the impurities Mn, Cr, Mo, or W on the heat capacity of Ni3Fe alloys is analysed as an example. The comparison of the theoretical results with the experimental data shows good qualitative agreement.
Citation Formats
S. Cavdar, E. Aksu, H. Koralay, H. Ozkan, N. Hasanlı, and I. Ercan, “Effect of B2O3 addition on the formation and properties of Tl-2212 and Tl-2223 superconductors,” PHYSICA STATUS SOLIDI A-APPLIED RESEARCH, pp. 272–276, 2003, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40621.