Uses of Nuclear Radiation :: essays research papers

Uses of nuclear radiationSmoke DetectorsSmoke alarms contain a shadowy source made of Americium-241.Alpha particles are emitted from here, which ionise the air, so that the air conducts electricity and a small current flows. If smoke enters the alarm, this absorbs the particles, the current reduces, and the alarm sounds.Thickness cut backIn paper mills, the thickness of the paper posterior be controlled by measuring how much beta radiation passes through the paper to a Geiger restitution. The counter controls the pressure of the rollers to give the correct thickness. With paper, or plastic, or aluminium foil, &61538, rays are used, because &61537, will not go through the paper. We choose a source with a long half-life so that it does not need to be replaced often. SterilisingEven after it has been packaged, da Gamma rays can be used to kill bacteria, mould and insects in food. This process prolongs the shelf-life of the food, but sometimes changes the taste. Gamma rays are also u sed to sterilise hospital equipment, especially plastic syringes that would be damaged if heated. Radioactive geological datingAnimals and plants have a cognize proportion of Carbon-14 (a radioisotope of Carbon) in their tissues. When they die they stop taking Carbon in, then the amount of Carbon-14 goes down at a known rate (Carbon-14 has a half-life of 5700 years). The age of the ancient organic materials can be found by measuring the amount of Carbon-14 that is left. Radioactive TracersThe most third estate tracer is called Technetium-99 and is very safe because it only emits gamma rays and doesnt cause much ionisation. Radioisotopes can be used for medical purposes, such as checking for a plugged kidney. To do this a small amount of Iodine-123 is injected into the patient, after 5 minutes 2 Geiger counters are placed over the kidneys. Also radioisotopes are used in industry, to detect leaking pipes. To do this, a small amount is injected into the pipe. It is then detected wi th a GM counter above ground. Cancer TreatmentBecause Gamma rays can kill living cells, they are used to kill cancer cells without having to resort to difficult surgery. This is called Radiotherapy? and works because cancer cells cant repair themselves when damaged by gamma rays, as healthy cells can.