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In this study, the process of explosive welding of Mg/Al plate is represented, and the interfacial behavior of two metals is researched. The objective of this work is to investigate the factors that affect the quality of explosive bonding and the distribution of physical parameters on the collision. A finite difference engineering package with smoothed particle hydrodynamics method is used to model the oblique impact of a thin flyer plate (Al) on a relatively thick base plate (Mg). Wavy interface and jetting phenomenon, which existed in the experiment, are well reproduced in the simulation. The contours of pressure, shear stress, velocity, and effective plastic strain of magnesium and aluminum are also distinctly described. The bonding turns out to be a possible solid-state welding process. The effective plastic strain exceeds a minimum value, and the shear stress is just the opposite sign in this simulation where available bonding occurred. Wave formation appears to be the result of variation in the velocity distribution on the interface and periodic disturbances of magnesium and aluminum. A transition from straight to wave occurs along the interface. High values of plastic strain of two metals are predicted on the interface.

Developing inexpensive and environmentally friendly no-metal photocatalyst is a promising strategy to addressing environmental issues. In this work, the metal-free catalyst g-CN/GQDs was synthesized through one-pot co-sintering method. The as-prepared photocatalysts showed enhanced photocatalytic activity for tetracycline (TC) degradation. Especially, the g-CN/GQDs-5 exhibited a nearly 30% improvement in TC degradation within 60 min of visible light irradiation compared to g-CN, and the kinetic constant was 1.8 times that of g-CN. The enhanced performance was attributed to the introduction of GQDs enhance the visible light absorption ability and suppress the recombination of photo-generated charges of g-CN. The capture experiment of active species showed that superoxide radicals played a major role in the degradation of TC in this system.

Aiming at the treatment of large volume of oil produced wastewater, the combined technology based on constructed wetland was applied for produced water treatment in a costal oil field. During the stable operation period, the treatment system maintained removal efficiency of 50.2% for chemical oxygen demand (COD), 100% for oil and 85.1% for ammonium nitrogen (NH3-N) under the gradient increase of salinity along the process. Meanwhile, this system has a good ability to adapt the influent fluctuation. When the oil in the influent fluctuated greatly between 11 mg/L to 147 mg/L, the effluent water quality remained stable. The treated water met the national discharge standard for water pollutants from the oilfield industry and can be used for the saline alkali beach wetland as supplement water.