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Superhydrophobic surface can be used in electronic devices to provide additional protection due to its waterproofing, anti-icing, low adhesion, and self-cleaning properties. In this study, a facile and efficient method is used to fabricate flexible, conductive, and superhydrophobic films. The copper-silver film with nanoparticles with the diameters of 50–500 nm was decorated on the flexible TPU substrate by electroless copper plating and spraying AgNO3 aqueous solution. After vacuum drying for 4 h, a superhydrophobic film was obtained without any surface modification. The formation mechanism of the micro-nano rough hierarchical structure and the reason for the formation of superhydrophobicity were studied, and the influence of the solution concentration and spraying times on the surface wettability during the spraying process was discussed. Through a series of tensile, bending, and impact tests, it was verified that the prepared flexible conductive superhydrophobic films had good mechanical stability. In addition, the film shows excellent low adhesion, self-cleaning, and conductivity in some experiments and is expected to be applied to flexible sensors, stretchable electronic devices, and wearable electronic devices. [ABSTRACT FROM AUTHOR]

Superhydrophobic materials are known for their vast range of applications and properties. We present a simple process to fabricate a superhydrophobic coating on 6061Al alloy via a route with chemical replacement and heat treatment. Through this route, a hierarchical morphology including microparticles and leaf-like microstructures was obtained and, upon modification by stearic acid, the prepared coatings show good water repellency with a water contact angle of 159.2 ± 0.3° and sliding angle of 4.5 ± 1.5°. Systematic studies have been conducted on the coatings fabricated under different processing conditions to obtain the best experimental parameters, and demonstrate the reaction mechanism and the good self-cleaning effect. The 3D simulated coating topography was characterized by Leica DCM 3D in the mesoscopic scale. Based on the topography, the simplified ideal truncated cone model and theoretical equation were obtained. According to the model, a qualitative result was drawn: the higher and sharper the convex structures are, the better is the superhydrophobicity. Furthermore, the presented process can be applied to larger, stable coatings with the controllable wettability for diverse applications. [ABSTRACT FROM AUTHOR]

In order to better control the water quality so as to inhibit the corrosion and scaling, the characteristics of the recirculating cooling system during shutdown state were studied. Related to chemical dosing cases and operating procedures, chemicals were screened and chemical dosing program were optimized. The designed chemical scheme were proved to be feasible by analyzing the water quality data and coupon corrosive test results. The study showed that since there were more dirts such as slime and corrosion products depositing in the pipeline under the shutdown state, under-deposit corrosion is prone to occur and the effects of corrosion inhibitors are degraded by reducing the contact between the metal surfaces and inhibitors. Cycles of concentration (CoC) is the key factor for the function of the corrosion inhibitors. Considering the high residence time of the chemicals in water at high CoCs, it would be better to choose the stable and persistant chemicals. Correspondingly, the chemicals need to be replaced when the CoC is reduced significantly. [ABSTRACT FROM AUTHOR]

Core-shell copper/silver bimetallic nanowires were prepared by replacement reaction with citric acid and polyvinylpyrollidone at room temperature. A uniform silver coating was obtained by strictly controlling the molar ratio of Ag/Cu. The copper/silver composite was characterized by X-ray diffraction, scanning electron microscopy, electron probe microanalysis and X-ray photoelectron spectroscopy. Microscopic analysis shows that a well-copper/silver core-shell structure was formed. Thermo-gravimetry and differential thermal analysis to the composite nanowires show that the silver coatings efficiently inhibit the oxidation of Cu. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: A nano-nickel catalyst was prepared by chemical reduction with N2H4·H2O, and was modified with ruthenium by chemical replacement. The nano-Ni and NiRu catalysts were characterized by X-ray diffraction, transmission electron microscope, and X-ray photoelectron spectroscopy. The catalysts were evaluated in the liquid phase hydrogenation of cinnamaldehyde and hydrodechlorination of chlorobenzene. The NiRu catalyst exhibited a much higher selectivity to the hydrocinnamaldehyde and a better hydrodechlorination activity and stability than those of the Ni catalyst. [Copyright &y& Elsevier]

Abstract: The distribution of 117 noncentrosymmetric niobates and tantalates over different crystal systems and types of space formation of Nb, Ta–O polyhedrons have been revealed. The dependence of polyhedron space formation in the crystal lattice of the compound on stoichiometric concentration (SC) of niobium and tantalum is established. Individual Nb, Ta–O octahedrons are found for SC=19–7.5, and chains and layers of the octahedrons appear in the range SC=11.0–5.2. Only frame formations of Nb, Ta–O octahedrons are possible under SC<5.2. [Copyright &y& Elsevier]

This work investigates element mobility and deformation mechanisms in sulphide-bearing quartz veins associated with a strike-slip fault exposed in the ONKALO™ Finnish deep repository for spent nuclear fuel (Olkiluoto Island, southwest Finland). It combines petrography, trace element mapping by Laser Ablation Inductively Coupled Plasma Time-of-Flight Mass Spectrometry (LA-ICP-TOFMS) and Electron Backscattered Diffraction (EBSD) analysis of representative microstructures. The fault core was reactivated by brittle deformation episodes assisted by hydrothermal fluid batches with distinct trace element signatures. LA-ICP-TOFMS element distribution maps and EBSD on sulphides reveal local, syn-deformational intragrain enrichment of primary and secondary elements (i.e., As, Co, Cu, Ag, Sn, Sb, Pb, Se, In, Te). Trace element enrichments occur by a combination of microscale plastic distortions and microfracturing at the reaction fronts. Fluid ingress along microcracks enhanced chemical replacement of pyrite that combined with element diffusion along dislocations and tilt boundaries controlled trace element mobility in sulphides at the small scale. At the scale of the vein system, the competence contrast between inclusions of soft sulphides in the harder host quartz may have favored local fracture nucleation and fluid flow. • Microstructural analysis and trace element mapping of sulphides. • Trace element mobility and chemical replacement of pyrite is promoted by diffusion and microfracture propagation. • Sb, Ag and Sn as most effective tracers of intragranular deformation in pyrite. [ABSTRACT FROM AUTHOR]