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Hiroshima

(Encyclopedia)Hiroshima hĭrˌōshēˈmə, hērōˈshmä [key], city, capital of Hiroshima prefectu...

Compton, Arthur Holly

(Encyclopedia)Compton, Arthur Holly, 1892–1962, American physicist, b. Wooster, Ohio, grad. College of Wooster (B.S., 1913), Ph.D. Princeton, 1916. He was professor and head of the department of physics at Washin...

Bohr, Aage Niels

(Encyclopedia)Bohr, Aage Niels ägə nēls bōr [key], 1922–2009, Danish physicist, Ph.D. Univ. of Copenhagen, 1954. He worked with his father Niels Bohr (who won the Nobel Prize in Physics in 1922) in the 1940s ...

autotroph

(Encyclopedia)autotroph ôtˈətrōfˌ [key], in biology, an organism capable of synthesizing its own organic substances from inorganic compounds. Autotrophs produce their own sugars, lipids, and amino acids using ...

Joule, James Prescott

(Encyclopedia)Joule, James Prescott jo͞ol, joul [key], 1818–89, English physicist. His scientific researches began in his youth when he invented an electromagnetic engine. Joule made valuable contributions to th...

solar cell

(Encyclopedia)solar cell, semiconductor devised to convert light to electric current. It is a specially constructed diode, usually made of forms of crystalline silicon or of thin films (as of copper indium gallium ...

photon

(Encyclopedia)photon fōˈtŏn [key], the particle composing light and other forms of electromagnetic radiation, sometimes called light quantum. The photon has no charge and no mass. About the beginning of the 20th...

actinide series

(Encyclopedia)actinide series, a series of radioactive metallic elements in Group 3 of the periodic table. Members of the series are often called actinides, although actinium (at. no. 89) is not always considered a...

blackbody

(Encyclopedia)blackbody, in physics, an ideal black substance that absorbs all and reflects none of the radiant energy falling on it. Lampblack, or powdered carbon, which reflects less than 2% of the radiation fall...

National Archives

(Encyclopedia)National Archives, official depository for records of the U.S. federal government, established in 1934 by an act of Congress. Although displeasure concerning the method of keeping national records was...