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ammonia

(Encyclopedia)ammonia, chemical compound, NH3, colorless gas that is about one half as dense as air at ordinary temperatures and pressures. It has a characteristic pungent, penetrating odor. Ammonia forms a minute ...

Sakmann, Bert

(Encyclopedia)Sakmann, Bert, 1942–, German biophysicist, M.D. Univ. of Göttingen, Germany, 1974. He has been a researcher at the Max Planck Institute for Biophysical Chemistry in Göttingen since 1974. Sakmann r...

manganese

(Encyclopedia)manganese măngˈgənēs, mănˈ– [key] [Lat.,=magnet], metallic chemical element; symbol Mn; at. no. 25; at. wt. 54.93805; m.p. about 1,244℃; b.p. about 1,962℃; sp. gr. 7.2 to 7.45, depending o...

Neher, Edwin

(Encyclopedia)Neher, Edwin, 1944–, German biophysicist, Ph.D. Technical Univ. of Munich, 1970. He has been a researcher at the Max Planck Institute for Biophysical Chemistry, Göttingen, Germany, since 1972. Nehe...

Yoshino, Akira

(Encyclopedia)Yoshino, Akira, 1948–, Japanese chemist, Ph.D. Osaka Univ., 2005. He was a researcher at Asahi Kasei Corp. from 1972 to 2017, when he became a professor at Meijo Univ., Nagoya, Japan. Akira received...

Benedict's solution

(Encyclopedia)Benedict's solution, deep-blue alkaline solution used to test for the presence of the aldehyde functional group, −CHO. The substance to be tested is heated with Benedict's solution; formation of a b...

electronegativity

(Encyclopedia)electronegativity ĭlĕkˌtrōnĕgətĭvˈətē [key], in chemistry, tendency for an atom to attract a pair of electrons that it shares with another atom (see chemical bond). For example, the molecule...

Solvay process

(Encyclopedia)Solvay process [for Ernest Solvay], commercial process for the manufacture of sodium carbonate (washing soda). Ammonia and carbon dioxide are passed into a saturated sodium chloride solution to form s...

fuel cell

(Encyclopedia)fuel cell, electric cell in which the chemical energy from the oxidation of a gas fuel is converted directly to electrical energy in a continuous process (see oxidation and reduction). The efficiency ...

cytochrome

(Encyclopedia)cytochrome sīˈtəkrōmˌ [key], protein containing heme (see coenzyme) that participates in the phase of biochemical respiration called oxidative phosphorylation. Cytochromes act as carriers of hydr...