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Abstract: Effect of interfacial shear strength on longitudinal tensile properties for SiCf/Ti–6Al–4V composites is investigated by Monte Carlo finite element method. A two-parameter Weibull function is employed to describe random distribution of fiber strength. Fiber breakage, matrix cracking and interfacial debonding are simulated by killing the element when stress applied to element exceeds corresponding strength and releasing coupled nodes when shear stress exceeds shear strength at interfaces. The results show that tensile strength of SiCf/Ti–6Al–4V composites keeps unchanged for various interfacial shear strengths, but low interfacial shear strength is advantageous to reduce catastrophic failure. Moreover, with low interfacial shear strength, fiber breakage in the composites is more inclined to be non-coplanar. In addition, tensile strength obtained from finite element method is compared with those predicted by global load-sharing model (GLS), local load-sharing model (LLS) and conventional rule of mixtures (ROM) and is identical with that obtained from LLS. [Copyright &y& Elsevier]

Abstract: This work reports a ceria solid and Pd/ceria catalyst prepared through a surfactant-templated synthesis route used for simultaneous abasement of NO and CO emissions. The surface features, textural properties and crystalline structure of ceria and Pd/ceria catalyst were studied by means of thermogravimetric analysis (TGA), N2 physisorption isotherms and in situ Fourier transform infrared (FT-IR) spectroscopy, high resolution electron transmission microscopy (TEM) and X-ray diffraction (XRD) techniques. In the calcination procedure, part of the adsorbed water on the surface of the solid was derived into unidentate and bidentate hydroxyls associated with surface cationic ions of ceria. The surfactant cations were strongly interacted with the solid during the preparation, which induces defects formation in the crystalline structure of the annealed ceria. The retained surfactant in the solid could be combusted to yield CO2, water and organic molecules with a small amount of coke-like deposits. The resultant ceria showed mesoporous texture and cubic phase containing lattice defects in the crystalline structure. The Pd/CeO2 catalyst was very active for NO reduction via CO with a high selectivity to N2. A 100% NO conversion with a selectivity to 100% N2 was achieved over the Pd/ceria catalyst at a reaction temperature of 300°C. The catalytic activity and selectivity of this catalyst are much superior to the catalysts of Pt or Rh supported on TiO2, Al2O3, TiO2–Al2O3 and ZrO2–Al2O3 prepared by a sol–gel method. A possible reaction mechanism of NO reduction by CO over the Pd/CeO2 catalyst was discussed. [Copyright &y& Elsevier]

The interfacial reaction zone of SCS-6 SiC/Ti2AlNb composites consists of two TiC layers with fine and large grains, respectively, and a layer of Ti3Si separating the large grained TiC layer with matrix. A discontinuous layer of Ti5Si3 was identified between the two TiC layers. Some Ti3AlC particles distribute within the Ti2AlNb matrix in thermally exposed composites. The formation mechanism of the reaction products was discussed. [Copyright &y& Elsevier]

Structure activity relationship (SAR) has been playing a more and more important role in medicine design. We presented here a preliminary investigation on the relationship between the structure of different phosphonates and the preparation of corresponding complexes labeled with 153Sm. By study of seven complexes, it was found that the number of -PO3H2 groups, the stereoscopic distance between them and the existence of strong electron-providing groups in the ligand molecule affected the preparation of 153Sm-complex. [ABSTRACT FROM AUTHOR]

Abstract: The relaxation behaviors of Ce65Al10Cu20Co5 and Zr46.75Ti8.25Cu7.5Ni10Be27.5 (Vit4) bulk glass-forming supercooled liquids were investigated by frequency-dependent heat capacity measurements on a temperature-modulated differential scanning calorimetry (TMDSC) apparatus. The relaxation behaviors of the investigated samples were well described by Kohlrausch–Williams–Watts (KWW) function. The temperature dependences of characteristic relaxation time of the glass-forming liquids were fitted by Vogel–Fulcher–Tamman (VFT) equation. The derived fragility index m shows that Ce65Al10Cu20Co5 (m =31) liquid is a stronger liquid than Vit4 (m =42). The sizes of cooperatively rearranging region (CRR) for Ce65Al10Cu20Co5 and Vit4 liquids were estimated to be 1.6 and 1.4nm, respectively. [ABSTRACT FROM AUTHOR]

Highlights: [•] Nanowire K0.19MnO2•0.2H2O is prepared by a hydrothermal method. [•] It presents better electrochemical behavior than K0.45MnO2•0.3H2O from the solid-state method. [•] Its capacitance is 148 F g−1 its cycling performance is excellent. [•] A supercapacitor based on activated carbon and nanowire K0.19MnO2•0.2H2O is assembled. [•] The supercapacitor delivers an energy density 41.3 Wh kg−1 based on the mass of the active electrode materials. [ABSTRACT FROM AUTHOR]

Abstract: Nanowire Na0.35MnO2 was prepared by a simple and low energy consumption hydrothermal method; its electrochemical performance as a cathode material for aqueous asymmetric supercapacitors in Na2SO4 solution was investigated. Due to the nanowire structure its capacitance (157 F g−1) is much higher than that of the rod-like Na0.95MnO2 (92 F g−1) from solid phase reaction although its sodium content is lower. When it is assembled into an asymmetric aqueous supercapacitor using activated carbon as the counter electrode and aqueous 0.5 mol L−1 Na2SO4 electrolyte solution, the nanowire Na0.35MnO2 shows an energy density of 42.6 Wh kg−1 at a power density of 129.8 W kg−1 based on the total weight of the two electrode material, higher than those for the rod-like Na0.95MnO2, with an energy density of 27.3 Wh kg−1 at a power density of 74.8 W kg−1, and that of LiMn2O4. The new material presents excellent cycling behavior even when dissolved oxygen is not removed from the electrolyte solution. The results hold great promise for practical applications of this cathode material since sodium is much cheaper than lithium and its natural resources are rich. [Copyright &y& Elsevier]

Abstract: Crystal structure of the compounds Co40V60−2x La x has been investigated by means of X-ray powder diffraction (XRD). The compounds crystallize in the tetragonal σ phase structure with the space group P42/mnm and form a solid solution with a solubility limit of x =9.52. The lattice parameters a, c and the unit cell volume V of the compounds decrease linearly with the La content. A structure model with a preferential substitution of La for V atoms on the 8j sites accompanied by the presence of vacancies on these sites is proposed for Co40V44La8. The proposal structure model gives a satisfactory fitting to the XRD data and a reasonable La content close to the nominal composition as well as a coincidence of the calculated density with the experimentally measured one. The preferential occupation of La atoms on the 8j site is discussed based on a consideration of geometric constrain and thermodynamics. [Copyright &y& Elsevier]

Abstract: The coherence transfer between stretching vibration modes of C–H bonds in the ethanol is detected by time-resolved multiplex CARS technique and it occurs via “through-bond transfer” pathway. The time scale and velocity of coherence transfer are estimated at 90fs and 1670m/s. Moreover, coherence transfer process requires vibrational modes of acceptor and donor are different. [Copyright &y& Elsevier]