By means of conventional current machining,ECM with fixed gap and interval feed as well as ECM with mixed mixed gas and fixed gap and interval feed,the paper gives an advice to improve processing accuracy and quality on internal surface of Laval nozzle.

Nowadays, semi-aerobic aged refuse bioreactor under batch injection conditions has been used to treat leachate, but capacity of the treatment is poor.

To investigate the possibility of improving treatment capacity of semi-aerobic aged-refuse bioreactors,continuous injection was compared with batch injection with leachate passing through the bioreactor in the laboratory.

This paper reported the removal efficiency of nitrogen in a downflow upflow constructed wetland purifying system with intermittent loading,and described the changes of temperature, dissolved oxygen and pH.