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  1. Excess steam from the drywell enters the wetwell water pool via downcomer pipes. SFP: spent fuel pool area. SCSW: secondary concrete shield wall. The Fukushima nuclear accident was a major nuclear accident at the Fukushima Daiichi nuclear power plant in Ōkuma, Fukushima, Japan which began on March 11, 2011.

    • 11 March 2011; 12 years ago
    • INES Level 7 (major accident)
    • 1 confirmed from radiation (lung cancer, 4 years later), and 2,202 from evacuation.
  2. Wikipedia is written by volunteer editors and hosted by the Wikimedia Foundation, a non-profit organization that also hosts a range of other volunteer projects : Commons. Free media repository. MediaWiki. Wiki software development. Meta-Wiki. Wikimedia project coordination. Wikibooks.

  3. The Chernobyl disaster [a] began on 26 April 1986 with the explosion of the No. 4 reactor of the Chernobyl Nuclear Power Plant, near the city of Pripyat in the north of the Ukrainian SSR, close to the border with the Byelorussian SSR, in the Soviet Union. [1] It is one of only two nuclear energy accidents rated at seven—the maximum severity ...

  4. en.wikipedia.org › wiki › IP_CodeIP code - Wikipedia

    • Origin of The Letters IP
    • Ipx9k and IPX9
    • United States
    • See Also

    In the original IEC 60529 standard from year 1976, the letters IP are used without providing an explanation, and referred as "characteristic letters".In the next editions of the standard, from years 1989 and 1999 respectively, the IP is explained to denote "international protection" on both French and English pages. According to the Finnish nationa...

    DIN 40050-9 extended the newer IEC 60529 rating system with an IP69K rating for high-pressure, high-temperature wash-down applications.Enclosures conforming with ISO 20653:2013 must be both dust-tight (IP6X) and able to withstand high-pressure and steam cleaning. The IPx9K standard was originally developed for road vehicles—especially those that ne...

    In the U.S., the National Electrical Manufacturers Association defines NEMA enclosure types in NEMA standard number 250. The following table outlines which IEC 60529 IP code each respective NEMA guideline meets. Ratings between the two standards are not directly equivalent: NEMA ratings also require additional product features and tests (such as fu...

  5. Main article: Light-emitting diode physics. In a light-emitting diode, the recombination of electrons and electron holes in a semiconductor produces light (be it infrared, visible or UV), a process called " electroluminescence ". The wavelength of the light depends on the energy band gap of the semiconductors used.

  6. In statistics, a normal distribution or Gaussian distribution is a type of continuous probability distribution for a real-valued random variable. The general form of its probability density function is. The parameter is the mean or expectation of the distribution (and also its median and mode ), while the parameter is its standard deviation.

  7. The theory of relativity usually encompasses two interrelated physics theories by Albert Einstein: special relativity and general relativity, proposed and published in 1905 and 1915, respectively. [1] Special relativity applies to all physical phenomena in the absence of gravity. General relativity explains the law of gravitation and its ...

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