By realizing in thin films a tensile stress state, superconductivity of 13 K was introduced into FeTe, a nonsuperconducting parent compound of the iron pnictides and chalcogenides, with a transition temperature higher than that of its superconducting isostructural counterpart FeSe. For these tensile stressed films, superconductivity is accompanied by a softening of the first-order magnetic and structural phase transition, and also, the in-plane extension and out-of-plane contraction are universal in all FeTe films independent of the sign of the lattice mismatch, either positive or negative. Moreover, the correlations were found to exist between the transition temperatures and the tetrahedra bond angles in these thin films.

FeSe(x) (x = 0.80,0.84,0.88,0.92) thin films were prepared on SrTiO(3)(001)(STO), (La,Sr)(Al,Ta)O(3)(001) (LSAT), and LaAlO(3)(001) (LAO) substrates by a pulsed laser deposition method. All of the thin films show single-phase and c-axis oriented epitaxial growth, and are superconducting. Among them, the FeSe(0.88) thin films show a T(c,onset) of 11.8 K and a T(c,0) of 3.4 K. The upper critical magnetic field is estimated to be 14.0 T.

Novel low dimensional quantum phenomena are expected at (110) LaAlO 3 /SrTiO 3 (LAO/STO) interfaces after the quasi two dimensional electron gas similar to that of (001) LAO/STO interfaces was found [G. Herranz et al., Sci. Rep. 2, 758 (2012) and A. Annadi et al., Nat. Commun. 4, 1838]. Here, two dimensional superconductivity of (110) LAO/STO samples with a superconducting transition temperature of 184 mK is demonstrated based on systematical transport measurements. The two dimensional characteristic of the superconductivity is confirmed by analyzing the Berezinskii-Kosterlitz-Thouless transition. The estimated superconductive thickness is about 18 nm. These features of superconductivity of (110) LAO/STO interfaces are comparable to those of (001) LAO/STO interfaces. This discovery may inspire a new round of upsurge on study of LAO/STO interfaces.

High crystalline anatase TiO2 and Nb:TiO2 thin films were fabricated on LaAlO3 (100) substrates by pulsed laser deposition. Room temperature ferromagnetism was obtained in Nb:TiO2 but absent in pure TiO2. The Kondo effect and anomalous Hall effect observed in metallic Nb:TiO2 strongly confirmed the existence of exchange interaction between intrinsic local magnetic moments and carriers. High energy resolution x-ray photoelectron spectroscopy studies of the Nb:TiO2 thin film revealed clear signals of Ti3+ and Nb4+ ions, which had one unpaired d electron responsible for the local magnetic moments. This result consisted quite well with the spin polarized first principle calculation.

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Transparent conducting materials with the ability of broadband electromagnetic shielding have a widespread range of applications in aerospace, medical equipment, and electronic communications. Achieving enhanced electromagnetic shielding effect without sacrificing much optical transparency is the technical trend in both academia and industries. Here, we experimentally propose a flexible hybrid film constructed by nano-printing based metal meshes and a graphene coating for the transparent electromagnetic shielding application. Numerical analysis is carried out to investigate optimal balance between electromagnetic shielding and optical transparency. In the experiment, enhanced shielding ability of hybrid film is observed without excessively sacrificing optical transmittance, compared to the reference group (the case only with metal mesh). Our work provides a hybrid platform for the high-performance optically transparent shielding materials for electromagnetic environment safety protection.

A drop-test rig is developed for the landing gear of a light multifunctional amphibious airplane based on its drop-test specifications. Several key technologies (including the schematic design of the light-aircraft drop test, the control-system design for the drop test, the high-speed turn of the wheel, the accurate lifting of the drop system, design of the measuring platform, and the imitation of the runway) are studied. Simultaneously, the system can realize accurate measurement and conduct the light-aircraft drop test with high-speed belt turn. Based on a drop test under initial parameters to get the friction between the tire and platform, and the elastic parameters of the wheel to simulate the interactions of components, the simulation models are repeatedly modified by analyzing the results of comparisons between drop test and simulation. Thus, an accurate model is established with optimal parameters, which verifies that the shock-absorbing properties of the landing gear with the optimal parameters meet the requirements of airworthiness rules, and the properties are greatly improved. According to the requirement of China Civil Aviation Regulations Order No. 132 (CCAR-23-R3) and the application of virtual prototype technology for the light multifunctional amphibious airplane, the adjusting-parameter drop test, the limited drop test, and the reserve-energy absorption drop test of the nose landing gear are accomplished. The limited load measured in the test is less than the design load, and the landing gear can bear the reserve-energy absorption drop test. The study shows that the adjusting-parameter drop test for establishing a simulation model is an available and reliable way to optimize the shock-absorbing properties of an amphibious-aircraft landing gear. The test system can be applied for the landing-gear drop-test of other light airplanes. Moreover, the test results can be used as the certification of the airworthiness for this airplane.Nomenclature A a = area where the piston rod squeezes out the air (except for the oil-hole area) A h = area where the piston rod squeezes out the oil (except for the oil-hole area) A 0 = sectional area of oil hole a t = acceleration of hanging basket C d = flow coefficient of the oil hole C = vertical damping coefficient of the wheel d m = diameter of the main oil hole d s = diameter of one-way oil hole F m t = total friction force between platform and the four supported pillars F x = horizontal load acting on the wheel F Y t = vertical load of the wheel F z = vertical load acting on the wheel K = vertical deformation coefficient of the wheel k va = calibration value of vertical acceleration sensor fixed on platform. k vg = calibration value of vertical load sensor M 1 = mass of platform N = number of wheel N Y t = inertia force of platform n n = inertial overload coefficient P S = atmospheric pressure P y t = resultant force measured by four sensors P 0 = initial pressure of buffer pt = tension-compression load of platform in the drop test S = stroke of buffer S max = maxi...