Improving the Corrosion Resistance of Aluminum Alloy by Creating a Superhydrophobic Surface Structure through a Two-Step Process of Etching Followed by Polymer Modification.

A multifunctional aviation aluminum alloy with good superhydrophobicity and corrosion resistance was prepared by a two-step process of etching followed by polymer modification. Meanwhile, micro- and nanostructures formed on the processed sample. Compared with bare sample, the static liquid contact angle on the as-prepared sample was increased by 100.8°. Further polarization tests showed that the corrosion potential of such a sample increased, and the corrosion current density decreased obviously, thus suggesting that the corrosion resistance of the modified sample was significantly improved. The same conclusion was confirmed by subsequent impedance testing. The work is of great economic value and practical significance to enhance the corrosion resistance of aviation actuator materials and also lays a foundation for future hydrophobic application research in aeronautical engineering.

Power production waste.

The storage of large amount of power production waste occupies huge land resource; moreover, the stored or discarded waste may pollute the water environment through changing the water pH, releasing the trace and toxic elements even radioactive elements, and so on by leachate. Therefore, the recycling and disposal of power production waste are important and necessary. This paper reviews the research literatures published in 2019 on power generation waste from coal-fired and nuclear power plants, mainly including the recycling of fly ash and flue gas desulfurization gypsum in construction industry and environmental application, the recovery and immobilization of different metals from coal combustion products and selective catalytic reduction catalysts, and the treatment and disposal of radioactive elements from nuclear power plants. Practioner points Coal-fired power plant waste can be applied for material preparation and wastewater purification. Valued and toxic metals are normally recovered or removed from spent selective catalytic reduction catalyst. Recovery and removal of radioactive elements is essential for nuclear power plant wastes disposal.

Electrochemical destruction of dinitrotoluene isomers and 2,4,6-trinitrotoluene in spent acid from toluene nitration process.

Mineralization of dinitrotoluene (DNT) isomers and 2,4,6-trinitrotoluene (TNT) in spent acid was conducted by in situ electrogenerated hydrogen peroxide. The electrolytic experiments were carried out to elucidate the influence of various operating parameters on the performance of mineralization of total organic compounds (TOC) in spent acid, including electrode potential, reaction temperature, oxygen dosage and concentration of sulfuric acid. It is worth noting that organic compounds could be completely mineralized by hydrogen peroxide obtained from cathodic reduction of oxygen, which was mainly supplied by anodic oxidation of water. Based on the spectra identified by gas chromatograph/mass spectrometer (GC/MS), it is proposed that oxidative degradation of 2,4-DNT and/or 2,6-DNT, 2,4,6-TNT results in o-mononitrotoluene (MNT) and 1,3,5-trinitrobenzene, respectively. Due to the removal of TOC and some amount of water, the electrolytic method established is promising for industrial application to regeneration of spent acid from toluene nitration process.

Decomposition of nitrotoluenes from trinitrotoluene manufacturing process by Electro-Fenton oxidation.

Oxidative degradation of dinitrotoluene (DNT) isomers and 2,4,6-trinitrotoluene (TNT) in spent acid was conducted by Electro-Fenton's reagents. The electrolytic experiments were carried out to elucidate the influence of various operating parameters on the performance of mineralization of total organic compounds (TOC) in spent acid, including reaction temperature, dosage of oxygen, sulfuric acid concentration and dosage of ferrous ions. It deserves to note that organic compounds could be completely destructed by Electro-Fenton's reagent with in situ electrogenerated hydrogen peroxide obtained from cathodic reduction of oxygen, which was mainly supplied by anodic oxidation of water. Based on the spectra analyzed by gas chromatograph/mass spectrometer, it is proposed that initial denitration of 2,4,6-TNT gives rise to formation of 2,4-DNT and/or 2,6-DNT, which undergo the cleavage of nitro group into o-mononitrotoluene, followed by denitration to toluene and subsequent oxidation of the methyl group. Owing to the removal of both TOC and partial amounts of water simultaneously, the electrolytic method established is potentially applied to regenerate spent acid from toluene nitration processes in practice.

[Observation of the promotion effect taurine on hepatic stellate cell's apoptosis in rat hepatic fibrosis model].

OBJECTIVE: To observe the effect of taurine on hepatic stellate cell's apoptosis induced by carbon tetrachloride (CCl4) in rats and to study its protective mechanisms. METHODS: CCl4-induced rat hepatic fibrosis was treated by taurine. Serum alanine aminotransferase (ALT), plasma protein, hyaluronic acid (HA), procollagen III (PC III), hepatic microsomal drug-metabolizing enzyme and anti-transforming growth factor beta1 (TGF-beta1) were determined. In addition, hepatic stellate cell's apoptosis and the pathological changes of liver tissue were observed under light microscope. RESULTS: The activity of serum ALT and the levels of serum HA, PC III were markedly reduced by taurine treatment. The hepatic cytochrome P450 (Cyt. P450) and cytochrome b5 (Cytb5) contents were increased by the same treatment. In addition, taurine could significantly inhibit the expression of TGF-beta1, promote the hepatic stellate cell's apoptosis, and relieve hepatic fibrosis. CONCLUSION: Taurine fulfills a role in promoting hepatic stellate cell's apoptosis in the case of hepatic fibrosis, it mitigates the liver injury, decreases the expression of TGF-beta1, and relieves hepatic fibrosis.