This master's thesis describes a phenomenon involving bulk nanobubbles. A method where a collimated laser beam is shined through the water, was chosen for seeding bulk nanobubbles. The observations were made using a rarefaction wave that expanded nanobubbles to observable sizes. Observations were made with a high-speed camera. Time, when one can observe expanded nanobubbles, is relatively short, ranging to a few microseconds. We devised an algorithm that combines number and size of nanobubbles into a single metric. We discovered that increasing the energy of a collimated laser beam results in an increase of the density of nanobubbles, until it reaches the saturation zone. We also discovered that nanobubbles can survive for tens of seconds in water.
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