An airbreathing jet engine is a jet engine that ejects a propelling jet of hot exhaust gases after first taking in atmospheric air, followed by compression, heating and expansion back to atmospheric pressure through a nozzle

Thermoacoustic engines (sometimes called "TA engines") are thermoacoustic devices which use high-amplitude sound waves to pump heat from one place to another (this requires work, which is provided by the loudspeaker) or use a heat difference to produce work in the form of sound waves (these waves can then be converted into electrical current the same way as a microphone does).

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A plasma propulsion engine is a type of electric propulsion that generates thrust from a quasi-neutral plasma. This is in contrast with ion thruster engines, which generate thrust through extracting an ion current from the plasma source, which is then accelerated to high velocities using grids/anodes. These exist in many forms (see electric propulsion). However, in the scientific literature, the term "plasma thruster" sometimes encompasses thrusters usually designated as "ion engines".

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Centrifugal-flow. In a centrifugal-flow engine, the compressor performs its job by picking up the entering air and accelerating it outwardly through centrifugal action. It basically consists of an impeller (rotor), a diffuser (stator), and a compressor manifold. The two main elements are the impeller and diffuser

Nanoparticles are very small and membrane filters are often not suitable for separating dispersion media. Therefore, centrifugation is used for separation. This technology makes it easier to rinse the nanoparticles.

A sonic boom is a sound associated with shock waves created when an object travels through the air faster than the speed of sound. Sonic booms generate enormous amounts of sound energy, sounding similar to an explosion or a thunderclap to the human ear. A decibel is the primary unit measurement of sound.

It is well known that super-cooled materials can be crystallized under the application of shock waves