Bipropellant attitude and orbit control engine is an important part of modern space vehicles and strategic and tactical weapons, which is widely used in orbit control, attitude adjustment and so on. In recent years, with the development of new aircraft or weapons, the requirement for engine performance has been increasing. It requires that specific impulse be increased and chamber pressure be increased, so as to reduce propellant consumption and engine weight, prolong engine life or increase the range of strategic weapons.

Tungsten molybdenum alloys can be used at higher temperatures than molybdenum or molybdenum alloys. Molybdenum-tungsten alloy has better conductivity, oxidation resistance and lower coating stress than molybdenum, which meets the requirement of sputtering target material for flat display film production line. Especially the Mo-W alloy with tungsten content of 3.5%25% is more suitable for high quality flat panel display.

Diesel engine oil is mainly composed of paraffin base oil or synthetic lubricant, which is prepared by adding many additives such as antioxidant, antiseptic, detergent and dispersant, antifriction agent and so on.

In recent years, selective catalytic reduction (SCR) has been widely used as the most efficient denitrification technology at present. The principle of this air pollution control technology is that in the presence of reducing agent NH₃, the flue gas containing NO_x reacts with the surface of the catalyst in a certain temperature range through the catalyst, making NO_x react with the surface of the catalyst. The NH₃ reaction is converted into harmless N₂ and H₂.