Three-dimensional (3D) platinum-cobalt alloy networks nanostructures with a high alloying degree were synthesized through a room temperature wet-chemical synthetic method using the K 2 PtCl 4 /K 3 Co(CN) 6 cyanogel as reaction precursor in the absence of surfactants and templates. The size, morphology and surface composition of platinum-cobalt alloy networks nanostructures were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectrum (EDS), selected area electron diffraction (SAED), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The 3D backbone structure and double-metallic property of the K 2 PtCl 4 /K 3 Co(CN) 6 cyanogel are responsible for the 3D structure and the high alloying degree of the as-prepared products, respectively. Compared to the pure Pt nanoparticles, 3D platinum-cobalt alloy networks nanostructures exhibit superior electrocatalytic activity and stability for the methanol oxidation reaction (MOR), which is ascribed to their unique 3D structure and alloy properties.

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Severe wear is a common damage mechanism in railway turnouts, which strongly affects the dynamic performance of railway vehicles and maintenance costs of tracks. This article explores the effects of profile wear on contact behaviors in the wheel-rail/switch contact and dynamic interaction, and nominal and measured worn turnout rail profiles are used as boundary conditions of wheel-rail contact. The calculation of the dynamic loads and the resultant contact stresses and internal stresses makes it possible to rationally design railway turnouts and correctly select the material to be applied for their components. For these reasons, the multi-body system SIMPACK and finite element software ANSYS are used to calculate the features of load and subsequently distributions of contact stresses and internal stresses in the regions of wheel-turnout components. The results show that profile wear disturbs the distribution of wheel-rail contact point pairs, changes the positions of wheel-rail contact points along the longitudinal direction, and affects the dynamic interaction of vehicle and turnout. For the measured profile in this article, profile wear aggravates vertical dynamic responses significantly but improves lateral dynamic responses. Profile wear disturbs the normal contact situations between the wheel and switch rail and worsens the stress state of the switch rail.

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