The activation of peroxymonosulfate (PMS) by cobalt?based catalysts has the advantages of high catalytic activity, simple operation, easy recyclability, and low cost. Hence, it has attracted much attention in the field of advanced oxidation processes in recent years. This paper reviewed typical methods for the synthesis of cobalt?based catalysts, including solid phase, gas phase, and liquid phase methods. Several types of cobalt?based catalysts for PMS activation, including cobalt oxides with special morphologies, supported cobalt catalysts, and cobalt?based composite metal oxides, were summarized. The applications of these cobalt?based catalysts in environmental remediation via PMS activation were also elaborated, such as the degradation of organic dyes, endocrine?disrupting chemicals, and pharmaceutical and personal care products. Finally, the current shortcomings of cobalt?based catalysts in PMS activation were summarized, and some future research directions in this area were proposed.

Massive electric charges will be generated due to the contact of oils flowing in the non⁃metallic pipeline with the inner wall of the pipeline. Excessive charge gathering discharge will cause spark discharge, which will lead to perforation of the pipe wall and fire, and seriously affect the normal production. Through analysis on the cause of static electricity and influencing factors, it is easy to find that the electrification rate is influenced by the oil flow rate, temperature, water content, pipe material and roughness. The results show that there is a positive correlation between the electrification rate and the oil flow rate, between the electrification rate and the pipe roughness; the rise of oil temperature adversely affects the accumulation of oil static; the electrification rate grows with the moisture content in a certain content range, and decreases with the increase of water content beyond the range; in combination with the existing experiment data, an oil flow⁃induced static model is built.

Non⁃metallic pipes are widely used in the gathering process and oil pipeline due to their excellent performance，but the calculation of the friction coefficient is still in the exploration stage. In this paper，the effects of the surface roughness and wettability of the inner wall surface of the oil pipeline on the frictional resistance of the fluid in the process are summarized，and the surface slip effect caused by the change of surface wettability is introduced. The wettability of the inner wall surface of the liquid and the pipe and the influence mechanism of the boundary slip effect on the friction coefficient along the path are discussed. The results show that the friction coefficient is affected by the roughness of the inner surface, the wettability of the fluid and the inner surface, the surface slip effect caused by the wettability and the surface tension of the liquid.

This article simulated three mortar systems including mineral filler⁃asphalt,mineral filler⁃emulsified asphalt residue and cement⁃emulsified asphalt residue in cold recycled mixture with emulsified asphalt. The results show that cement⁃emulsified asphalt residue mortar owns higher modulus than the other two mortars because of cement hydration. The change of modulus and phase angle is different from that of ordinary mineral powder⁃asphalt mortar and mineral powder⁃emulsified asphalt mortar, and does not change linearly monotonously with powder⁃to⁃binder ratio. At the same time, the interface adhesive ability of cement⁃ emulsified asphalt residue is similar to that of the mineral filler⁃asphalt mortar, and much higher than that of the mineral filler⁃emulsified asphalt residue mortar in a lower filler dosage. In the process of mixture production, emulsified asphalt provides the initial stability of the mixture, and cement hydration and the formation of composite mortar system are the guarantee of the final cold recycled mixture strength.