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radical, in chemistry

(Encyclopedia)radical, in chemistry, group of atoms that are joined together in some particular spatial structure and that take part in most chemical reactions as a single unit. Important inorganic radicals include...

pure-food laws

(Encyclopedia)pure-food laws: see food adulteration. ...

Pure Land Buddhism

(Encyclopedia)Pure Land Buddhism or Amidism, devotional sect of Mahayana Buddhism in China and Japan, centering on worship of the Buddha Amitabha. According to the Pure Land Sutras, composed in India in the 2d cent...

Universal Postal Union

(Encyclopedia)Universal Postal Union (UPU), specialized agency of the United Nations since 1948, with headquarters at Bern, Switzerland. Established in 1875 following adoption of the Universal Postal Convention, it...

World Conservation Union

(Encyclopedia)World Conservation Union: see International Union for the Conservation of Nature and Natural Resources. ...

industrial union

(Encyclopedia)industrial union, labor union composed of all the workers in a given industry, regardless of skill, craft, or occupation (as opposed to the craft union, in which all members are of one skill, such as ...

union, labor

(Encyclopedia)union, labor, association of workers for the purpose of improving their economic status and working conditions through collective bargaining with employers. Historically there have been two chief type...

alkene

(Encyclopedia)CE5 Alkenes alkene ălˈkēn [key], any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon double bonds (see chemical bond). Alkenes with only one double bond h...

alkyne

(Encyclopedia)CE5 Alkynes alkyne ălˈkīn [key], any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon triple bonds (see chemical bond). Alkynes with one triple bond have t...

hassium

(Encyclopedia)hassium hăsˈēəm, häsˈ– [key], artificially produced radioactive chemical element; symbol Hs; at. no. 108; mass number of most stable isotope 277; m.p., b.p., sp. gr., and valence unknown. Situ...