122 type pnictide superconductors are of particular interest for high-field applications because of their large upper critical fields H c2 (> 100 T) and low anisotropy γ (<2). Successful magnet applications require fabrication of polycrystalline superconducting wires that exhibit large critical current density J c , which is limited by poor grain coupling and weak-link behavior at grain boundaries.Here we report our recent achievement in the developing Sr 0.6 K 0.4 Fe 2 As 2 tapes with transport J c up to 0.1 MA/cm 2 at 10 T and 4.2 K. This value is by far the highest ever recorded for iron based superconducting wires and has surpassed the threshold for practical application. The synergy effects of enhanced grain connectivity, alleviation of the weak-link behavior at grain boundaries, and the strong intrinsic pinning characteristics led to the superior J c performance exhibited in our samples. This advanced J c result opens up the possibility for iron-pnictide superconducting wires to win the race in high-field magnet applications.

Electric field modulation of magnetism and electric properties inLa-Ca-MnO3/Pb(Zr0.52Ti0.48)O3 magnetoelectric laminate J. Appl. Phys. 113, 17C712 (2013); 10.1063/1.4795871 Stress-controlled Pb(Zr0.52Ti0.48)O3 thick films by thermal expansion mismatch between substrate and Pb(Zr0.52Ti0.48)O3 filmHydrothermally synthesized piezoelectric Pb(Zr 0.52 Ti 0.48 )O 3 fibers were used as a mechano-catalyzer to degrade acid orange 7 dye wastewater via the mechano-catalytic effect, which was achieved as a product of the piezoelectric effect and the electro-catalytic effect. When subjected to mechanical vibration, the Pb(Zr 0.52 Ti 0.48 )O 3 fibers bend, which in turn induces electric charges on the surfaces of the fibers via the piezoelectric effect. The piezoelectrically induced electric charges induce chemical degradation reactions in the dye wastewater through the electro-catalytic effect. A high mechano-catalytic degradation ratio of $80% was achieved for the acid orange 7 solutions ($30 lmol/l). The piezoelectrically induced mechano-catalytic effect thus provides a highly efficient and reusable technology for dye wastewater degradation applications. V C 2014 AIP Publishing LLC. [http://dx.

High-performance Sr0.6K0.4Fe2As2 (Sr-122) tapes have been successfully fabricated using hot pressing (HP) process. The effect of HP temperatures (850–925°C) on the c-axis texture, resistivity, Vickers micro-hardness, microstructure and critical current properties has been systematically studied. Taking advantage of high degree of c-axis texture, well grain connectivity and large concentration of strong-pinning defects, we are able to obtain an excellent Jc of 1.2 × 105 A/cm2 at 4.2 K and 10 T for Sr-122 tapes. More importantly, the field dependence of Jc turns out to be very weak, such that in 14 T the Jc still remains ~ 1.0 × 105 A/cm2. These Jc values are the highest ever reported so far for iron-pnictide wires and tapes, achieving the level desired for practical applications. Our results clearly strengthen the position of iron-pnictide conductors as a competitor to the conventional and MgB2 superconductors for high field applications.