I T Kato et al Japanese Journal of Applied Physics Impact Factor 106 1990 293

I t kato et al japanese journal of applied physics

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I. T. Kato et al., Japanese Journal of Applied Physics (Impact Factor: 1.06). 1990; 29(3). Sintered Bi (1.4) Pb (0.6) Sr 2 Ca 2 Cu 3 O 10 pellets were irradiated one after one with 1 or 3 MeV electrons up to 8 x 10 to the 19th/sq m at ambient temperature. It is measured that electrica l resistivity was a temperature‟s function. The transition (zero resistance) temperature Tc decreased almost linearly with electron dose after a transient regime concurrently with a linear increase in the resistivity. The zero resistance temperature measured with 120 kA/sq m current density was increased from 96.5 to 102.8 K by 3 MeV electron irradiation to 1.0 x 10 19 th/sq m, and then decreased upon further irradiation. [21] II. K. Yasuda et al., Electron Irradiation Effects in a Bi 0.7 Pb 0.3 SrCaCu 1.8 Oxide Superconductor, physica status solidi (a) 05/1991; Tested samples were Bi 0.7 Pb 0.3 SrCaCu 1.8 Oy that was irradiated with 7 MeV electrons in air, liquid nitrogen, and water. Since it was irradiated in low temperature, the transition temperature Tc is shifted to lower temperatures with a degradation rate of 5 K/1019e/cm2, and the resistivity in the normal state increases with 0.7 mΩ cm/1018 e/cm2. The susceptibility-temperature curves are also shifted to lower temperatures along the temperature axis, but there is no appreciable change in the absolute susceptibility for irradiations up to 3.6 × 10 18 e/cm 2 . The critical current density Jc decreases slightly for the irradiation in air. The degradation of the samples irradiated in liquid nitrogen is similar to that in air. The degradation of the samples irradiated in water is significant, but the superconductive properties are not lost completely with an electron irradiation dose of 1 × 10 18 e/cm 2 . [22]
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25 III. K. Shiraishi et al., Electron irradiation effects on a Bi(1.4)Pb(0.6)Sr2Ca2Cu3O10 superconductor, Japanese Journal of Applied Physics 08/1992; 31(8). A Bi 1.5 Pb 0.5 Sr 2 Ca 2 Cu 3 Ox ceramic was sequentially irradiated with 3 MeV electrons at a dose rate of 2.5× 10 17 m -2 up to a dose of 2.0× 10 20 m -2 at ambient temperature, and the transport critical current density was measured as a function of temperature. The critical current density in zero field at temperatures below 65 K was increased by irradiation to 1.0× 1020 m-2, and the radiation effect was more prominent at lower temperature. Upon further irradiation to 2.0× 1020 m-2, the critical current density was reduced in the low temperature regime to a level less than the pre irradiation value. [23]
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26 CHAPTER 3 METHODOLOGY 3.1 INTRODUCTION The main part of this project was preparing and synthesizing the sample using Solid State Method. Then, the several tests had done to verify the effect of Nanosize MgO addition. In this section the procedures of the chosen synthesis method “Solid State Meth od” to prepar e the sample will be discussed along with the tests that had been done.
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