Diesel engine air start system check valves are opened by （）

The additional mark （）in the Classification Certificate for Machinery means propulsion apparatus is remotely controlled on the navigating bridge control station, and engine assembly control station is unmanned periodically.

（）are used to digest the sewage to produce innocuous sludge in a biological sewage treatment plant.

The condensers located in various stages of a flash evaporator are cooled by（）

For a given exhaust gas boiler, what is the quantity of its evaporation mainly determined?（）

Refrigerant entering the compressor of a refrigeration system should be in which of the following conditions?（）

By comparing the exhaust gas temperature of each cylinder, the operator can determine if the load is balanced throughout the engine. The device most commonly used is a（）

The Port State Control officer may witness a fire drill carried out by the crew assigned to these duties on the（）

Flame failure in an automatically fired auxiliary boiler can from a/an （）

The cetane rating of diesel fuel is an indication of the （）