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adenosine triphosphate

(Encyclopedia)CE5 Adenosine triphosphate (ATP) adenosine triphosphate (ATP) ədĕnˈəsēn trīˌfŏsˈfāt [key], organic compound composed of adenine, the sugar ribose, and three phosphate groups. ATP serves ...

gamma-ray astronomy

(Encyclopedia)gamma-ray astronomy, study of astronomical objects by analysis of the most energetic electromagnetic radiation they emit. Gamma rays are shorter in wavelength and hence more energetic than X rays (see...

Goeppert-Mayer, Maria

(Encyclopedia)Goeppert-Mayer, Maria, 1906–72, German-American nuclear physicist, Ph.D. Univ. of Göttingen, 1930. She was a researcher at Johns Hopkins (1931–39), Columbia (1939–46), Argonne National Laborato...

Manhattan Project

(Encyclopedia)Manhattan Project, the wartime effort to design and build the first nuclear weapons (atomic bombs). With the discovery of fission in 1939, it became clear to scientists that certain radioactive materi...

Anzus Treaty

(Encyclopedia)Anzus Treaty ănˈzəs [key], defense agreement signed in 1951 by Australia, New Zealand, and the United States. The name Anzus is derived from the initials of the three signatory nations. As a result...

transducer

(Encyclopedia)transducer, device that accepts an input of energy in one form and produces an output of energy in some other form, with a known, fixed relationship between the input and output. One widely used class...

Raman effect

(Encyclopedia)Raman effect räˈmən [key], appearance of additional lines in the spectrum of monochromatic light that has been scattered by a transparent material medium. The effect was discovered by C. V. Raman i...

heterotroph

(Encyclopedia)heterotroph hĕtˈərətrōfˌ [key], living organism that obtains its energy from carbohydrates and other organic material. All animals and most bacteria and fungi are heterotrophic. In contrast, aut...

technetium

(Encyclopedia)technetium tĕknēˈshēəm [key] [Gr. technetos=artificial], artificially produced radioactive chemical element; symbol Tc; at. no. 43; mass no. of most stable isotope 98; m.p. 2,200℃; b.p. 4,877�...

saprophyte

(Encyclopedia)saprophyte săpˈrəfītˌ [key], any plant that depends on dead plant or animal tissue for a source of nutrition and metabolic energy, e.g., most fungi (molds) and a few flowering plants, such as Ind...