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  2. Beta particle - Wikipedia

    en.wikipedia.org/wiki/Beta_particle

    Beta radiation, consisting of electrons or positrons, is stopped by a thin aluminum plate, but gamma radiation requires shielding by dense material such as lead or concrete. [1] A beta particle, also called beta ray or beta radiation (symbol β), is a high-energy, high-speed electron or positron emitted by the radioactive decay of an atomic ...

  3. Betavoltaic device - Wikipedia

    en.wikipedia.org/wiki/Betavoltaic_device

    A betavoltaic device (betavoltaic cell or betavoltaic battery) is a type of nuclear battery which generates electric current from beta particles (electrons) emitted from a radioactive source, using semiconductor junctions. A common source used is the hydrogen isotope tritium. Unlike most nuclear power sources which use nuclear radiation to ...

  4. Radioactive contamination - Wikipedia

    en.wikipedia.org/wiki/Radioactive_contamination

    The radiation warning symbol (trefoil) Alpha radiation consists of helium-4 nucleus and is readily stopped by a sheet of paper. Beta radiation, consisting of electrons, is halted by an aluminium plate. Gamma radiation is eventually absorbed as it penetrates a dense material. Lead is good at absorbing gamma radiation, due to its density.

  5. Ionizing radiation - Wikipedia

    en.wikipedia.org/wiki/Ionizing_radiation

    Ionizing radiation (US, ionising radiation in the UK), including nuclear radiation, consists of subatomic particles or electromagnetic waves that have sufficient energy to ionize atoms or molecules by detaching electrons from them. [1] Some particles can travel up to 99% of the speed of light, and the electromagnetic waves are on the high ...

  6. Radioactive tracer - Wikipedia

    en.wikipedia.org/wiki/Radioactive_tracer

    A radioactive tracer, radiotracer, or radioactive label is a synthetic derivative of a natural compound in which one or more atoms have been replaced by a radionuclide (a radioactive atom). By virtue of its radioactive decay, it can be used to explore the mechanism of chemical reactions by tracing the path that the radioisotope follows from ...

  7. Photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Photosynthesis

    Photosynthesis (/ ˌfoʊtəˈsɪnθəsɪs / FOH-tə-SINTH-ə-sis) [ 1 ] is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their metabolism.

  8. Radiation - Wikipedia

    en.wikipedia.org/wiki/Radiation

    In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or a material medium. [1][2] This includes: electromagnetic radiation consists of photons, such as visible radiation. particle radiation consists of particles of non-zero rest energy, such as beta radiation (β) acoustic radiation ...

  9. Photosynthetically active radiation - Wikipedia

    en.wikipedia.org/wiki/Photosynthetically_active...

    Besides the amount of radiation reaching a plant in the PAR region of the spectrum, it is also important to consider the quality of such radiation. Radiation reaching a plant contains entropy as well as energy, and combining those two concepts the exergy can be determined. This sort of analysis is known as exergy analysis or second law analysis ...