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The present study experimentally investigates the effects of plasma discharges on the stabilization of lifted non-premixed jet flames in a stream of co-flow air. The plasma discharge is produced on the sharp edge of the fuel nozzle exit, facilitating its impact on flame stabilization. It is observed that the application of plasma discharges has an impact on the enhancement of flame lift-off velocity, lift-off height, and hysteresis phenomenon and leads to plasma-attached flames, plasma-enhanced lifted flames, and plasma-ineffective lifted flames, depending on flame lift-off conditions. A maximum enhancement of approximately 84% is observed for the flame lift-off velocity when the co-flow velocity is sufficiently low. As the co-flow velocity or the jet Reynolds number is low, the flame is anchored at the nozzle by the discharge. As the co-flow velocity or the jet Reynolds number is increased, the flame detaches but with a decrease in lift-off height compared to the flame without the discharge. If the co-fl...

The welding experiment of Q245R and Q345R thickness plate was carried out by double wire submerged arc welding. And the welding results were analyzed by macroscopic metallography, microstructure observation and mechanical properties of welded joints. Results show that the double wire submerged arc welding can produce larger penetration, and ensure the weld width. It have better appearance of weld, and the mechanical performance fully meet the requirements of production technology. At the same time, comparison and analysis from the aspects of welding deposition efficiency about the single and double wire submerged arc welding welding process, further illustrates the double wire submerged arc welding can effectively improve the efficiency of welding, reducing welding costs, to meet the requirements of modern industrial manufacture various. It has a good application prospect.

The synergistic effect of ultrasound and certain chemicals on cells is known as sonodynamic therapy (SDT). It has been reported that the direct sonochemical and subsequent redox reactions induced by SDT treatment can lead to apoptotic cell death. However, the detailed biologic mechanism about it is not well understood until now. In this study the effect of low-intensity ultrasound on Hepatoma-22 cells (H22) in the presence of the sonosensitizing drug protoporphyrin IX (PpIX) was evaluated at different incubation times after sonication. Trypan blue exclusion was used to detect cell viability. The presence of apoptotic cells was identified by 4'-6-diamidino-2-phenylindole (DAPI) nuclear staining and transmission electric microscope (TEM) observation. An inverted confocal laser scanning microscope was used to detect the release of mitochondrial protein cytochrome c (Cyt c) and the redistribution of Bcl-2 family proteins Bid and Bax. Additionally, the generation of intracellular reactive oxygen species (ROS) and the loss of mitochondria membrane potential (MMP) were quantificationally measured by a fluorescence microplate reader. The results indicated that the synergistic cytotoxicity of PpIX and ultrasound increased in a time-dependent manner and the mitochondria damage may be the main factor for sonodynamically induced apoptosis by PpIX in H22 cells.