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Poor corrosion resistance of magnesium alloys dramatically limits their application in corrosive environments.Microarc oxidation(MAO) technology can prepare a ceramic-like coating on the surface of magnesium alloy，which is an effective method to improve its corrosion resistance.Due to the film formation mechanism of MAO technology，there are many pores and cracks in the coating，and usually the coating is mainly composed of MgO，which would absorb water or deliquesce in wet and acidic environments，making the coating present bad corrosion resistance.Incorporating ZrO2 with excellent chemical stability and high hardness into magnesium alloy MAO coating to obtain a coating mainly composed of ZrO2 or a ZrO2-containing coating can improve the protection effect on the substrate.This paper reviewed the research progresses of the preparation technology，film formation mechanism and corrosion resistance of ZrO2-containing MAO composite coatings on magnesium alloys from the aspects of electrolyte，electric parameter，two-step MAO process，and combining MAO with other surface treatment techniques.In addition，the problems and shortcomings of each research direction were analyzed.In the future，it is necessary to optimize the electrolyte composition to ensure its stability and effectiveness and clarify the consumption and replenishment rules of each electrolyte component during the usage.The two-step MAO process should be further studied to obtain a composite MAO coating with better protection effect on the magnesium alloy matrix.Combination of MAO and other surface treatment techniques should be explored to utilize the advantages of two technologies and coatings comprehensively.The temperature field distribution and MAO coating forming mechanism can be further analyzed based on the structure transformation of ZrO2 at different temperatures.

Ti-Al-based alloys, particularly two-phase TiAl and Ti3Al alloys, have garnered significant attention as potential replacements for various high-temperature structural materials due to their exceptional properties, including low density, oxidation resistance, and high strength at elevated temperatures. Despite these advantages, experimental studies on the microstructure evolution of Ti-Al-based alloys under complex conditions remain challenging to observe and characterize. This review article examines the current research on molecular dynamics (MD) simulations of Ti-Al-based alloys, focusing on two-phase Ti-Al alloys, Ti-Al amorphous alloys, Ti-Al composite materials, and the welding and multi-layer/film applications of Ti-Al alloys. This review highlights the unique capabilities of MD simulations in predicting the behavior of Ti-Al-based alloys and addresses existing scientific challenges. Furthermore, this article discusses future research directions and development prospects in this field. [ABSTRACT FROM AUTHOR]

Microarc Oxidation (MAO) technology can prepare a ceramic-like oxide coating. It is an effective technique to increase the wear and corrosion resistance of magnesium alloys. The MAO coating has many defects such as holes and cracks. As well, the coating on magnesium alloys typically consists mainly of MgO, which absorbs water or dissolves in a humid or acidic environment. Therefore, the MAO coatings are not adequate for the long-term protection of magnesium alloys. MAO coatings that are composed of ZrO2, or which have ZrO2 with a compact microstructure, can improve the protection of magnesium alloys. This paper critically summarizes the progress of MAO coatings containing ZrO2 on magnesium alloys from four aspects: electrolyte compositions, electrical parameters, the two-step MAO process, and post-treatment of MAO coating. The future research directions for MAO coatings containing ZrO2 on magnesium alloys are discussed. [ABSTRACT FROM AUTHOR]

Bi4TaO8Cl and Bi4TaO8Cl:Gd3+ photocatalysts were synthesized by the solvothermal technique. The phase, microstructure, optical properties, and photocatalytic activities were investigated. Both Bi4TaO8Cl and Bi4TaO8Cl:Gd3+ have the singly orthorhombic phase and the flower‐like hierarchical structure. The Bi4TaO8Cl:Gd3+ has higher photocatalytic activity of MB than that of Bi4TaO8Cl under visible light irradiation. The higher photocatalytic activity of Bi4TaO8Cl:Gd3+ is induced by its lower band gap energy, the higher efficiency charge separation, and transfer process, as well as the photogenerated charge carriers with a longer time, which are confirmed by the longer absorption band edge, lower emission intensity, and higher photocurrent under visible light irradiation. The trapping experiments and electron spin resonance results suggest that ˙O2− is the predominant active species for the photocatalysis of MB by Bi4TaO8Cl and Bi4TaO8Cl:Gd3+ under visible light irradiation. [ABSTRACT FROM AUTHOR]

To improve both oxygen evolution efficiency and stability at high temperatures, Mn, Mn+Mo, Mn+Mo+V, and Mn+Fe+V oxide electrodes were prepared on a Ti substrate, with an intermediate layer of IrO2, by an anodic deposition method. The crystal structure, surface morphology, pore size distribution, specific surface area, and voltammetric charge were then characterized for each electrode. The results demonstrated that for Mn-O electrodes, the preferential orientation of the (100) crystal plane and the mesopore structure played negative roles in the oxygen evolution reaction. On the basis of the electrocatalytic properties of MnO2- based electrodes in seawater, the outer surface voltammetric charge at a scan rate of 500 mV·s−1 was shown to effectively indicate whether oxygen evolution reactions were preferred over chlorine evolution reactions. The Mn-O electrode exhibited oxygen evolution efficiency of only 47.27%, whereas the Mn+Mo, Mn+Mo+V and Mn+Fe+V oxide electrodes displayed oxygen evolution efficiency of nearly 100%. This means that adding Mo, V, and Fe elements to the electrode can improve its crystal structure and morphology as well as further enhancing its oxygen evolution efficiency. [ABSTRACT FROM AUTHOR]

Abstract: Al2O3/ZrO2 composite coating was prepared on 2A70 aluminum alloy by microarc oxidation (MAO) in a phosphate electrolyte containing K2ZrF6. The effects of K2ZrF6 in the electrolyte on the coating thickness, surface morphology, elemental composition and abrasive resistance were investigated. The results indicated that the MAO coating thickness increase due to the addition of K2ZrF6 in the electrolyte. In the electrolyte containing 6.0g/L K2ZrF6, the coating was the most uniform and compact. The MAO coating formed in the electrolyte without K2ZrF6 was mainly composed of γ-Al2O3 and a little α-Al2O3. Zirconium in the form of t-ZrO2 was detected in the MAO coatings formed in the electrolyte containing K2ZrF6, and the Zr content increases with increasing concentration of K2ZrF6. A γ-Al2O3 and t-ZrO2 nanocomposite coating was formed in the electrolyte containing 6.0g/L K2ZrF6, and which exhibited the highest abrasive resistance. [Copyright &y& Elsevier]

The detection of volatile organic compounds (VOCs) in breath has become a potential method for early cancer screening. Although this approach has attracted increasing attention from the both scientific and medical communities, it has not received appreciable traction in the clinical setting. There are two main obstacles. One involves the identification of specific biomarkers or combinations thereof especially in early cancer. The other is the lack the specialized equipment for breath analysis having the appropriate sensitivity and specificity. Using metabolomics, this chapter examines the research strategies involving gas biomarkers in cancer patient breath, cancer cell gas metabolites and synthetic biomarkers. We briefly explore gas biomarkers of seven cancers and introduce principles of detection and clinical application. Large analytical instruments and small sensor technology are highlighted. Challenges to VOC analysis are presented including clinical use, extraction and detection, miniaturization efforts and examination of metabolic VOC pathways. Finally, VOCs in cancer and in exhaled breath detection technology are summarized and future prospects explored., (Copyright © 2024. Published by Elsevier Inc.)