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proton

(Encyclopedia)proton, elementary particle having a single positive electrical charge and constituting the nucleus of the ordinary hydrogen atom. The positive charge of the nucleus of any atom is due to its protons....

perturbation

(Encyclopedia)perturbation pŭrˌtərbāˈshən [key], in astronomy and physics, small force or other influence that modifies the otherwise simple motion of some object. The term is also used for the effect produce...

matter

(Encyclopedia)matter, anything that has mass and occupies space. Matter is sometimes called koinomatter (Gr. koinos=common) to distinguish it from antimatter, or matter composed of antiparticles. The atomic th...

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...

Chauvin, Yves

(Encyclopedia)Chauvin, Yves, 1930–2015, French chemist, b. Menen, Belgium, grad. Lyon School of Chemistry, Physics, and Electronics (CPE), 1954. Chauvin was a research engineer (1960–91) and then research direc...

graphene

(Encyclopedia)graphene, virtually transparent, highly conductive carbon material in which the atoms are organized into a honeycomblike arrangement and form a thin sheet that is one atom thick. Andre Geim and Konsta...

mercaptan

(Encyclopedia)mercaptan thīˈōl [key], any of a class of organic compounds containing the group –SH bonded to a carbon atom. The volatile low-molecular-weight mercaptans have disagreeable odors. Mercaptans are ...

Politzer, Hugh David

(Encyclopedia)Politzer, Hugh David, 1949–, American physicist, b. Mineola, N.Y., Ph.D. Harvard, 1974. Politzer has been a professor at the California Institute of Technology since 1977. He was a co-recipient, wit...

free radical

(Encyclopedia)free radical, in chemistry, a molecule or atom that contains an unpaired electron but is neither positively nor negatively charged. Free radicals are usually highly reactive and unstable. They are pro...

Gross, David Jonathan

(Encyclopedia)Gross, David Jonathan, 1941–, American particle physicist, b. Washington, D.C., Ph.D. Univ. of California, Berkeley, 1966. Gross was a professor at Princeton from 1969 to 1997, when he joined the fa...