Eco-friendly underwater cleaning of ship hulls

Biofouling is the growth of algae, mussels, and other marine organisms on the hull of a ship. The fouling increases the flow resistance of the ship—and thus increases fuel consumption and CO2 emissions. Mechanical cleaning ...


A fairy-like robot flies by the power of wind and light

The development of stimuli-responsive polymers has brought about a wealth of material-related opportunities for next-generation small-scale, wirelessly controlled soft-bodied robots. For some time now, engineers have known ...


A new way to assess radiation damage in reactors

A new method could greatly reduce the time and expense needed for certain important safety checks in nuclear power reactors. The approach could save money and increase total power output in the short run, and it might increase ...

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A laser is a device that emits light (electromagnetic radiation) through a process called stimulated emission. The term laser is an acronym for light amplification by stimulated emission of radiation. Laser light is usually spatially coherent, which means that the light either is emitted in a narrow, low-divergence beam, or can be converted into one with the help of optical components such as lenses. Typically, lasers are thought of as emitting light with a narrow wavelength spectrum ("monochromatic" light). This is not true of all lasers, however: some emit light with a broad spectrum, while others emit light at multiple distinct wavelengths simultaneously. The coherence of typical laser emission is distinctive. Most other light sources emit incoherent light, which has a phase that varies randomly with time and position.

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