Highly stable dispersions of nanosized copper particles with an average particle size less than 2 nm were synthesized using a straightforward, cost-effective, and green method. Nontoxic L-ascorbic acid was utilized as both a reducing agent and capping agent precursor in aqueous medium. The copper particles were characterized by ultraviolet-visible spectroscopy, transmission electron microscopy, and Fourier-transform infrared spectroscopy The mechanism of L-ascorbic acid on the reduction and stabilization of copper nanoparticles is also discussed.

The fabrication of a superhydrophobic surface is demonstrated via a wet chemical route, and this method offers advantages of being cleanroom free, cost efficiency, and wide applicability. The preferable growth of ZnO crystalline forms a microstructured surface, and a variety of alkanoic acids were adopted to tune the surface wettability. Although all surfaces show an advancing contact angle greater than 150 degrees , they substantially differ in the wetting mechanisms. It is found that only when the length of alkanoic acid is greater than 16, the microstructured surface shows a stable superhydrophobicity, in which the Cassie state dominates. While for those moderate-length alkanoic acids (C8-C14), their corresponding surfaces have a tendency to fall into the Wenzel state and display a great contact angle hysteresis.

A cellulose sponge with properties of superhydrophilicity and under-water superoleophobicity gives 99.94% separation efficiency in oil–water emulsion separation.

The application of epoxidized rapeseed oil as a biodegradable lubricant is described. The epoxidation treatment has no adverse effect on the biodegradability of the base stock. Epoxidized rapeseed oil has superior oxidative stability compared to rapeseed oil based on the results of both oven tests and rotary oxygen bomb tests. Moreover, the oxidative stability can be dramatically promoted by the addition of a package of antioxidants. The epoxidized rapeseed oil has better friction-reducing and extreme pressure abilities according to tribological investigations. Formation of a tribopolymerization film is proposed as explanation of the tribological performance of epoxidized rapeseed oil.

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ABSTRACT： ： ： ：In order to improve mechanical durability, polyurethane (PU) needs to be modified to enhance tribological and anti-corrosion properties. In this work, we fabricated a series of PU composite coatings reinforced with functionalized graphene (FG) and functionalized graphene oxide (FGO). The structural and morphological features of the composite coatings were characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, transmission electron microscopy and scanning electron microscopy. Results showed that the dispersion and compatibility of graphene and graphene oxide were improved via chemical modification. Moreover, they effectively enhanced the tribological and anti-corrosion properties of PU composite coatings, whose optimized additive range were between 0.25wt% and 0.5wt%. The effect depends on the balance of lubrication and barrier of fillers and cracks generated by them. Finally, in comparison with FG/PU coatings, FGO/PU coatings exhibited better tribological property but worse anti-corrosion property owing to abundant oxygenated groups of GO. They lead to stronger interfacial interaction between FGO and PU matrix, but destroyed the graphene lattice structure to some extent.

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