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Highlights: [•] The shear force of solder joints decreased with increasing reflow time. [•] The shear force of solder joints increased with increasing displacement rate. [•] The fracture mode transformed from ductile to brittle with increasing reflow time and displacement rate. [Copyright &y& Elsevier]

The urea oxidation reaction (UOR) offers an attractive strategy to replace the oxygen evolution reaction (OER) for energy-saving hydrogen production due to its favorable thermodynamic property, but its development is hindered by the lack of efficient and cost-effective electrocatalysts. In this study, nickel-tellurium (Ni-Te) grown on 3D nickel foam was successfully synthesized using a simple and facile electrodeposition method. The electrodeposition process of Ni-Te follows the three-dimensional instantaneous nucleation/growth mechanism controlled by diffusion. The apparent activation energy (E a) of Ni-Te in the electrodeposition process is as low as 36.5 kJ∙mol-1. Lattice distortion structure obtained by electrodeposition modifies the intrinsic electronic structure and optimizes the adsorption energy of intermediates. Thanks to the synergistic effects of fast electron transport, superhydrophilic surface and nanoflake structure, the prepared Ni-Te electrocatalyst shows excellent activity toward UOR with a low potential of 1.503 V vs. RHE at 100 mA·cm-2 and a small Tafel slope (63.6 mV·dec-1) in 1.0 M KOH containing 0.33 M urea solution. [Display omitted] • Ni–Te catalyst was synthesized by electrodeposition for UOR catalysis. • Ni–Te exhibits a low potential of 1.346 V @10 mA·cm−2 and a Tafel slope of 63.6 mV·dec-1 in UOR. • Inducing lattice distortion, superhydrophilicity and nanoflake structure benefit the optimized UOR activity. [ABSTRACT FROM AUTHOR]

Bimetal oxide-based compounds have potential in the degradation of antibiotics in wastewater. In this study, cobalt-ferrite-coated multi-walled carbon nanotubes (CoFe 2 O 4 /MWCNTs) have been synthesized by solvothermal method and characterized. Then, the degradation of sulfadiazine (SDZ) by CoFe 2 O 4 /MWCNTs activated peroxymonosulfate (PMS) system was determined, mainly including the effects of CoFe 2 O 4 /MWCNTs dosage, PMS concentration, solution pH, initial SDZ concentration, and co-existing anions on the degradation of SDZ. Based on reactive oxygen species identification and XPS analysis, the possible reaction mechanisms were investigated. In addition, the potential degradation pathways of SDZ were discussed. The results showed that CoFe 2 O 4 /MWCNTs exhibited superior catalytic activity and stability toward SDZ removal, and 97.5% of SDZ was degraded within 30 min under the condition of CoFe 2 O 4 /MWCNTs dosage 0.3 g/L, PMS concentration 0.5 mM and solution pH 7. The possible mechanism of PMS activation by CoFe 2 O 4 /MWCNTs involved both free-radical and non-radical pathways, and the generated reactive species (SO 4 •−, •OH, O 2 •− and 1O 2) were responsible for the degradation of SDZ. In addition, four potential degradation pathways were proposed and 15 intermediates were identified. In view of the ecotoxicity assessment, it was found that the toxicity of the degradation intermediates was lower than that of SDZ. Overall, this study established an effective strategy for PMS activation to remove recalcitrant organic pollutants in wastewater. • CoFe 2 O 4 /MWCNTs was prepared by a solvothermal method. • SDZ can be removed completely within 60 min by CoFe 2 O 4 /MWCNTs activated PMS system, • Free-radical and non-radicals attended CoFe 2 O 4 /MWCNTs activated PMS system. • The toxicity assessment of SDZ degradation process was conducted by ECOSAR. [ABSTRACT FROM AUTHOR]

Coralliform polyaniline (PANI) nanorods were successfully grafted onto the surface of Li 0.35 Zn 0.3 Fe 2.35 O 4 (LZFO) particles by interfacial polymerization. The LZFO particles were prepared by sol-gel method and decorated via the coralliform PANI nanorods. The structure and morphology were systematically investigated by Fourier transform infrared spectra (FTIR), X-ray diffraction (XRD), and scanning and transmission electron microscopy (SEM/TEM). The LZFO/PANI nanocomposite with novel coralliform microtopography was prepared by using an efficient, simple, and controllable two-step method. The electromagnetic parameters with different weight ratios of ferrite and aniline monomer were investigated at the 0.5–18 GHz frequency range by using vector network analyzers. Reflection loss (R L ) of different thicknesses was calculated using the electromagnetic parameter according to the transmission line theory. The LZFO/PANI nanocomposite, optimized with a weight ratio of 1:2 of ferrite to aniline monomer, showed that the maximum R L value reached −36.9 dB at 12.4 GHz with the thickness of 2.1 mm, and the bandwidth below −10 dB was at 4.24 GHz (11.26–15.5 GHz). The enhanced microwave absorption properties of LZFO/PANI nanocomposites were chiefly attributable to the coralliform structure and improved impedance matching between the dielectric and magnetic loss. This study proves that LZFO/PANI nanocomposites can be a potential candidate for efficient microwave absorption materials. [ABSTRACT FROM AUTHOR]

• The corrosion effect of TiO 2 nanofluids antifreeze on engine was studied at 88 ℃. • The co-existence of SDBS and TiO 2 nanoparticles can shield Cl- and inhibit corrosion. • The best corrosion inhibition occurred at 2500 mg/L SDBS and 0.1 vol% TiO 2. [Display omitted] The antifreeze mainly composed of aqueous ethylene glycol is easily contaminated with chloride ions, which will accelerate corrosion of aluminum alloy in the components of the engine heat transfer system at long-term high temperatures. In the present work, corrosion behavior of 3003 aluminum (Al) alloy with the addition of TiO 2 nanoparticles and sodium dodecyl benzene sulfonate (SDBS) in aqueous ethylene glycol (EGW) containing chloride ions at 88 ℃ was examined. The corrosion behavior of 3003 Al alloy was investigated by potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). The scanning electron microscopy (SEM), energy dispersion X-ray (EDX) and Fourier transform infrared spectroscopy (FT-IR) were used to explore the morphology, structure, and composition of the sediment on the alloy surface. And the Turbiscan Lab (TLAB) dispersion stability analyzer was utilized to test the dispersion stability of TiO 2 nanofluids. The experimental results demonstrated that the co-existence of TiO 2 and SDBS performed the significant corrosion inhibition, and can protect alloy from chloride ions. [ABSTRACT FROM AUTHOR]

In this work, SiO 2 was evenly coated on dry yeast as biological template by sol-gel method, and the internal substances of yeast were removed at 700 °C to obtain hollow silicon template. Then, RF aerogel (carbon source) was used to wrap the silicon template. After carbonization treatment, carbon thermal reduction reaction was carried out at 1400 °C to obtain hollow SiC spheres (HSS). Under the coating of RF aerogel, the hollow SiO 2 maintained its complete physical shape in the process of high-temperature synthesis, and the final product was hollow ellipsoidal silicon carbide with the maximum diameter of about 4.3 μm and the minimum diameter of about 3.5 μm, basically keeping the shape of yeast. The basic properties of the products were characterized by XRD, FT-IR, SEM, TEM and Tg, the absorption properties of the products were analyzed by VNA. The research found that the absorption performance of the hollow SiC with yeast morphology increased significantly in the frequency band of 2–18 GHz. When the thickness is 3.1 mm, the hollow SiC has the maximum reflection loss of −51.74 dB at 12.08 GHz. When the thickness is 4.0 mm, it has an effective absorption frequency width of 6.05 GHz, which has obvious advantages over SiC without special hollow morphology. The effect of hollow structure on the electromagnetic properties of SiC is discussed in detail. Image 1 • The prepared hollow silicon carbide has a complete morphology of yeast (3.5-4.3 μm). • Hollow silicon carbide can significantly improve the absorption and attenuation of electromagnetic wave. • When the thickness is 4.0 mm, hollow silicon carbide has an effective absorption bandwidth of 6.05 GHz. [ABSTRACT FROM AUTHOR]