And the chemical constituents of Stachys geobombycis was primarily demonstrated according to precipitadon reaction or color reaction with various indicator.
A floorstand for handwheel actuated valves allows operation from above.Included is handwheel, non-rising stem, fittings, extension, and floorstand with gate position indicator.
Bench of closed circuit cooling tower that is composed of boiler ,exchanger, orifice flowmeter, water pump, micromanometer , heat indicator and so on is established.
The direction of luminiferous evacuation indicator is fixed in complex fire accident scene,that is difficult to play safe and effective role in the evacuation instructions.