August 25, 1908 (, Shigenobu, July 29,), the death of Henri Becquerel, French physicist and discoverer of natural radioactive.




radioactive elements from unstable atomic nuclei spontaneously emit rays (such as ��-rays, ��-rays, �� rays, etc.) and the decay of the formation of stable elements to stop radiation (decay products), this phenomenon is called radioactive. The energy released during the decay is called the decay energy. Atomic number 83 (bismuth) or more of the elements have radioactive radioactive, but some atomic number 83 the following elements (such as technetium).
Antoine Henri Becquerel (Antoine Henri Becquerel, 1852 December 15, 1908 August 25, days), French physicist. , Won the 1903 Nobel Prize in Physics for his discovery of the phenomenon of natural radioactivity.
Becquerel, the choice of material is uranium and potassium sulphate. He let these two materials are exposed to the sun, and then with black paper material exposed photographic film package together. Negatives, rinsed after a period of time and shows the image of the uranium crystals.
Becquerel to the conclusion that: "radiant energy emitted by the phosphorescent material through the opaque paper. Beginning, he thought the uranium will absorb the energy of the sun, and then emit X-rays. the
in Paris, February 26, 1896 and February 27, the sky is cloudy, Becquerel originally intended wrapped uranium and photographic film to the sun, had returned to the drawer. March 1, he rinse the film, originally thought to only see fuzzy images not think they see a very clear image, so he surprised. Uranium does not require external sources of energy, such as sunlight also can emit radiation, he found radioactive materials spontaneously emit radiation.
Comments: He made a great discovery for the benefit of unlimited. (Lsjt.net)