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This paper examined the wing rock motion of an aircraft model with a configuration of slender fuselage, 81°-swept strake wing, 48°-swept wing and twin vertical tails. These experiments covered the alpha range of 0° to 70° and zero sideslip with a Reynolds number (Re) of 1.2×105.The roll motion pattern can be divided into three regions: No wing rock region (α=0-20°), micro-vibration region (α=20°-35° and α=60°-70°), wing rock region (α=35°-60°). At the wing rock region, the motion was not induced by asymmetric vortices on slender forebodythrough the analysis of response relationship between wing rock motion and location of nose perturbation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Incorporation of Cu3SbSe4 in β-Zn4Sb3 can yield reduction of k and enhancement of PF. [•] ZT=1.23 is achieved at 648K for f(Cu3SbSe4)/β-Zn4Sb3 with f =15 vol.%. [•] Second phase of larger S can improve the thermoelectric performance of the host. [ABSTRACT FROM AUTHOR]

Abstract: Here we apply high resolution angle-resolved photoemission spectroscopy (ARPES) using a wide excitation energy range to probe the electronic structure and the Fermi surface topology of the Ba1− x K x Fe2As2 (T c =32K) superconductor. We find significant deviations in the low energy band structure from that predicted in calculations. A set of Fermi surface sheets with unexpected topology is detected at the Brillouin zone boundary. At the X-symmetry point the Fermi surface is formed by a shallow electron-like pocket surrounded by four hole-like pockets elongated in Γ−X and Γ−Y directions. [Copyright &y& Elsevier]

Abstract: YBa2Cu4O8 is a stoichiometric oxide superconductor of T c∼80K. Unlike YBa2Cu3O7− δ , this compound is free from oxygen vacancy or twin formation and does not have any microscopic disorder in the crystal. Doping with Ca raises its T c to 90K. The compound is a promising superconductor for technological application. Up to now, single crystals have not been grown without using specialized apparatus with extremely high oxygen pressure up to 3000bar and at over 1100°C due to the limited range of reaction kinetics of the compound. This fact has delayed the progress in the study of its physical properties and potential applications. We present here a simple growth method using KOH as flux that acts effectively for obtaining high-quality single crystals in air/oxygen at the temperature as low as 550°C. As-grown crystals can readily be separated from the flux and exhibit a perfect orthorhombic morphology with sizes up to 0.7×0.4×0.2mm3. Our results are reproducible and suggest that the crystals can be grown using a conventional flux method under ambient condition. [Copyright &y& Elsevier]

Abstract: We have performed 75As nuclear magnetic resonance measurements on a single crystal of the hole-doped superconductor Ba0.72K0.28Fe2As2 (T c =31.5K). The spin–lattice relaxation rate 1/T 1 decreases below T c with no coherence peak and shows a step-wise variation at low temperatures, which is indicative of multiple superconducting gaps. In the normal state, we find that Fe antiferromagnetic spin fluctuations are anisotropic. [ABSTRACT FROM AUTHOR]