[en] Bi-Sr-Ca-Cu-O superconductors have been prepared from the constituent pure metals by mechanical alloying in air succeeding sintering at high temperatures in flowing oxygen. X-ray patterns from the milled powders indicate that the dissolution of Cu and Bi in the Bi-Sr-Ca-Cu matrix occurs progressively with milling. However, a prolonged milling resulted in amorphous-like diffraction patterns with the first peak centered around 30⁰. The particle size rapidly asymptotes to a fixed value near 30 h milling. The X-ray patterns of the sintered materials are in good agreement with those of the orthorhombic structure reported in the superconducting Bi-base oxides. The low T_c phase in the Bi-base oxides was identified from the resistivity and susceptibility measurements. The superconducting temperature appears to be sensitive to the milling conditions

[en] P-loop open string amplitude is constructed as the integral over the real section of the moduli space. The modular group of the open string is presented

[en] The authors show that the relativistic Vlasov equation derived recently by the authors from the Walecka model under the local density and the classical approximations is equivalent to the covariant Vlasov equation derived by Else et al. via the Wigner operator

[en] The authors derived the quantum mechanical versions of infinite number of conservation laws associated with Derivative Nonlinear Schrodinger equation with the help of a methodology used in string theory. The renormalised version of the conserved quantities are obtained with explicit forms of the counter terms

[en] Recent experiments on the surface impedance of the high temperature superconductors are summarized. The overall temperature dependence of the penetration depth is in broad qualitative agreement with conventional pairing, but with an anomolous power law behavior observed at low temperatures. The surface resistance is orders of magnitude larger than estimates based on the Mattis-Bardeen theory. One possibility is unconventional pairing, but structural inhomogenities are the most likely explanation for the experimental results

[en] The transport critical current measurements were performed on polycrystalline YBa₂Cu₃O_chi in various thermal and magnetic field cyclings. The magnetic history and magnetic field dependence of J_c reveals that there are many strong links between grains in YBa₂Cu₃O_chi polycrystalline samples

[en] In an effort to synthesize copper oxides involving intergrowth structures, the authors have found several compositions giving rise to high-temperature superconductivity, most of them containing the 123-type phase. A novel 123 superconducting phase is found in the Y-Sr-Cu-O system. More interestingly, an oxide of the Y-Ba-La-Cu-O system showed zero resistivity around 210Κ. Existence of extra Cu-O layers in some of the intergrowth structures may also lead to high-T_c superconductivity

[en] Thin films of BaO, Y₂O₃, Eu₂O₃ and CuO have been prepared by plasma-enhanced CVD using heptanedionato- and pentanedionato- complexes of the metals as precursors

[en] The authors study the asymptotic behavior of the ordering process of quenched systems with long-distance hopping. Based on a newly proposed computer model of such systems, two dimensional simulations are performed to investigate the scaling law for the scattering structure function

[en] A transmission electron microscopy (TEM) study was made on Y-Ba-Cu-O superconductors prepared by plasma spraying which is a useful technique in forming and manufacturing of brittle materials. Amophous region and transitional phases with certain orientation relationship were found between YBa₂Cu₃O_7-x grains