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A sandwich-like 2D-mesoporous-carbon/MoS2 -nanosheet heterostructure is fabricated for the first time. The hybrid structure is composed of three well-stacked monolayers: an ordered-mesoporous-carbon monolayer, a MoS2 monolayer, and a further ordered-mesoporous-carbon monolayer. This unique heterostructure exhibits excellent electrochemical performance as an anode material for lithium-ion batteries.

ZSM-5 zeolite with a hexagonal cubic morphology was synthesized by a hydrothermal method using Triton X-100, a nonionic surfactant. The samples prepared with and without the surfactant were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy, N2 adsorption, high resolution transmission electron microscopy (TEM), high resolution scanning electron microscopy, energy dispersive X-ray analysis, and NH3 temperature-programmed desorption. The XRD patterns confirmed the formation of a pure ZSM-5 crystalline phase without secondary phases. TEM images revealed that the hexagonal cubes were made of peanut-shaped nanoparticles with voids. The catalytic activity of the zeolite samples was evaluated using the selective oxidation of benzyl alcohol with tertiary-butyl hydrogen peroxide as the oxidant at 90 ?. The surfactant-assisted preparation yielded a zeolite that gave a higher conversion than the one prepared in the absence of the surfactant. The catalyst was retrieved and reused four times without significant loss in activity and selectivity. � 2014, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Nickel-base superalloy, Waspaloy, was linear friction welded (LFWed) under different axial shortening conditions of 2.0, 3.4, and 4.6 mm. The tensile properties and microhardness of the weldments were investigated in the as-LFWed condition and compared with those in the post-weld heat treated (PWHTed) condition. Mechanical properties were related to microstructures following examination by optical microscopy, high resolution scanning electron microscopy, and electron backscatter diffraction (EBSD). Analyses of the EBSD results in terms of the misorientation angle distribution, which represents the stored energy, were performed. In the as-LFWed condition, the yield strength (YS) and ultimate tensile strength (UTS) increased with axial shortening due to greater expulsion of the softened interfacial material toward the periphery as flash. In contrast, with increasing axial shortening the total elongation initially remained constant and then decreased. This was also related to the expulsion of the softened interfacial material into the bifurcated flash. Extensive dissolution of the strengthening phase (γ′) in the weld area during linear friction welding (LFW) contributed to the lower YS and UTS in the as-welded condition compared to the PWHTed condition where the γ′ particles were recovered. After performing post-weld heat treatment (PWHT), the total elongation improved due to the relaxation of storedmore » energy and grain growth in the thermomechanically affected zone (TMAZ). - Highlights: • Tensile property and microstructure in Waspaloy linear friction welds were studied. • Yield strength and ultimate tensile strength increased with axial shortening. • Elongation initially remained constant and then decreased with axial shortening. • Post-weld heat treat recovered dissolved γ′ particles and increased weld strength. • Stored energy relaxation during post-weld heat treatment improved weld elongation.« less

Ultrafine-grained materials produced by different severe plastic deformation methods show very high strengths but their tensile ductility is often very low. In the present work, we demonstrate an approach for retaining high strength while recovering ductility in a Cu-3 at.% Ag alloy through cold rolling and short-time annealing. X-ray line profile analysis of cold-rolled and annealed samples reveals the development of a heterogeneous solute atom distribution due to the dissolution of nanosized Ag particles in some regions of the matrix. In regions with higher solute (Ag) content, the high dislocation density present following rolling is stabilized, while in other volumes the dislocation density is decreased. High-resolution scanning electron microscopy confirms the presence of regions of varying Ag content in the matrix. Microstructure analysis of the rolled and annealed samples revealed bimodal grain size, dislocation density and solute Ag distributions as well as nanosized Ag precipitation. The as-rolled samples exhibit high tensile strengths of ?600-700 MPa with negligible uniform elongation (?1%). After short-time annealing the strength decreases only slightly to ?550-620 MPa with significant improvement in uniform elongation (from 1 to 10%); this is mainly attributed to the bimodal microstructure. � 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

SnF 2 of various crystallite sizes have been obtained by mechanical milling. Further, the crystallite size dependent conduction characteristics of SnF 2 have been investigated by X-Ray Diffraction, High Resolution Scanning Electron Microscopy and Impedance Spectroscopy techniques. The crystallite size and microstrain developed during the milling process have been calculated by using Scherrer's semi-empirical formula. Further, an attempt is made to correlate the conductivity results of mechanically milled samples with the crystallite size and microstrain. In all cases, the temperature dependent conductivity plot obeys the Arrhenius behavior. The enhancement in conductivity of SnF 2 is found to be of two orders of magnitude after simply milling for 10 h. � 2012 Elsevier B.V. All rights reserved.