Bike pedals used to put a metal screw cap to protect the bearings from contamination. Now, instead, use the plastic plugs, which are often lost. Rescue plastic or nylon tubes from medical bubbles. Such substitutes being kept quite steady.
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The competition, held in Prague in 1983, General attention was attracted by two unusual the box. Despite the fact that over micromachines was just a few days before the official starts,...
Ultrasound against rodents
Among elastic oscillations of air, ultrasound (from Latin ultra — beyond, more, above), inaudible to the human ear and with a lower frequency limit conventionally taken as 20 kHz, has long...
