Aiming at the features of the mute circuit of PVW2000 series video-recorder with power on, illustrates their general principles, offers the inner circuit to the power on pulse generator M51957BL, the parameters for the main parts and the reference voltage for every key points in different conditions.

In order to study the start-up and shut-down characteristics of R410A split air-conditioners under cooling mode, the refrigerant distribution in the system as well as temperatures and pressures at the suction and discharge point were measured during first 30 min at start-up and shut-down, respectively.

Improving on the pneumatic system of DDS tapping machine;

Tapping machine is one of the main equipments of blast furnace.

Due to the design disadvantage of DDS pneumatic tapping machine for 3# blast furnace in Meishan Ironworks,the tapping machine bogie has to stay for five seconds when it switches from the advance to retreat.