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Avogadro, Amedeo, conte di Quaregna

(Encyclopedia)Avogadro, Amedeo, conte di Quaregna ämādāˈō kônˈtā dē kwärāˈnyä ävōgäˈdrō [key], 1776–1856, Italian physicist, b. Turin. He became professor of physics at the Univ. of Turin in 182...

Cannizzaro, Stanislao

(Encyclopedia)Cannizzaro, Stanislao stänēsläˈō kän-nēt-tsäˈrō [key], 1826–1910, Italian chemist. From 1861 he was professor at Palermo and from 1871 at Rome, where he was also a member of the senate and...

Gerhardt, Charles Frédéric

(Encyclopedia)Gerhardt, Charles Frédéric shärl frādārēkˈ zhārärˈ [key], 1816–56, French chemist, b. Strasbourg. He revived the theory of acid radicals, which he called the theory of residues, and did va...

Moseley, Henry Gwyn Jeffreys

(Encyclopedia)Moseley, Henry Gwyn Jeffreys mōzˈlē [key], 1887–1915, English physicist, grad. Trinity College, Oxford, 1910. He began his research under Ernest Rutherford while serving as lecturer at the Univ. ...

surface chemistry

(Encyclopedia)surface chemistry, study of chemical reactions in which the reactants are first adsorbed onto a surface medium (see adsorption) that then acts as a catalyst for the reaction; after the reaction the pr...

clock

(Encyclopedia)CE5 A pendulum clock: Weight-driven clock mechanism clock, instrument for measuring and indicating time. Predecessors of the clock were the sundial, the hourglass, and the clepsydra. See also watc...

atom

(Encyclopedia)CE5 Bohr-Rutherford atom CE5 Probability distribution of the electron in the hydrogen atom: A. Ground state B. Highly excited state atom [Gr.,=uncuttable (indivisible)], basic unit of matte...

erythromycin

(Encyclopedia)erythromycin ĭrĭthˌrōmīˈsĭn [key], any of several related antibiotic drugs produced by bacteria of the genus Streptomyces (see antibiotic). Erythromycin is most effective against gram-positive ...

neomycin

(Encyclopedia)neomycin nēˌōmīˈsĭn [key], broad spectrum antibiotic effective against both gram positive and gram negative bacteria (see Gram's stain). It interferes with protein synthesis in sensitive bacteri...

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