vacuum generation

  • 21Persistent carbene — A stable carbene: isolated 1,3 dimesitylimidazol 2 ylidene in a Schlenk flask (stir bar also present). A persistent carbene (also known as stable carbene or Arduengo carbene) is a type of carbene demonstrating particular stability. The best known …

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  • 22Fusion power — The Sun is a natural fusion reactor. Fusion power is the power generated by nuclear fusion processes. In fusion reactions two light atomic nuclei fuse together to form a heavier nucleus (in contrast with fission power). In doing so they release a …

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  • 23technology, history of — Introduction       the development over time of systematic techniques for making and doing things. The term technology, a combination of the Greek technē, “art, craft,” with logos, “word, speech,” meant in Greece a discourse on the arts, both… …

    Universalium

  • 24KABBALAH — This entry is arranged according to the following outline: introduction general notes terms used for kabbalah the historical development of the kabbalah the early beginnings of mysticism and esotericism apocalyptic esotericism and merkabah… …

    Encyclopedia of Judaism

  • 25china — /chuy neuh/, n. 1. a translucent ceramic material, biscuit fired at a high temperature, its glaze fired at a low temperature. 2. any porcelain ware. 3. plates, cups, saucers, etc., collectively. 4. figurines made of porcelain or ceramic material …

    Universalium

  • 26China — /chuy neuh/, n. 1. People s Republic of, a country in E Asia. 1,221,591,778; 3,691,502 sq. mi. (9,560,990 sq. km). Cap.: Beijing. 2. Republic of. Also called Nationalist China. a republic consisting mainly of the island of Taiwan off the SE coast …

    Universalium

  • 27Italy — /it l ee/, n. a republic in S Europe, comprising a peninsula S of the Alps, and Sicily, Sardinia, Elba, and other smaller islands: a kingdom 1870 1946. 57,534,088; 116,294 sq. mi. (301,200 sq. km). Cap.: Rome. Italian, Italia. * * * Italy… …

    Universalium

  • 28Physical Sciences — ▪ 2009 Introduction Scientists discovered a new family of superconducting materials and obtained unique images of individual hydrogen atoms and of a multiple exoplanet system. Europe completed the Large Hadron Collider, and China and India took… …

    Universalium

  • 29Transmission electron microscopy — A TEM image of the polio virus. The polio virus is 30 nm in size.[1] Transmission electron microscopy (TEM) is a microscopy technique whereby a beam of electrons is transmitted through an ultra thin specimen, interacting with the specimen as it… …

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  • 30NSA encryption systems — The National Security Agency took over responsibility for all U.S. Government encryption systems when it was formed in 1952. The technical details of most NSA approved systems are still classified, but much more about its early systems has become …

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