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weight

(Encyclopedia)weight, measure of the force of gravity on a body (see gravitation). Since the weights of different bodies at the same location are proportional to their masses, weight is often used as a measure of m...

absolute zero

(Encyclopedia)absolute zero, the zero point of the ideal gas temperature scale, denoted by 0 degrees on the Kelvin and Rankine temperature scales, which is equivalent to −273.15℃ and −459.67℉. For most gase...

streptomycin

(Encyclopedia)streptomycin strĕpˌtōmīˈsĭn [key], antibiotic produced by soil bacteria of the genus Streptomyces and active against both gram-positive and gram-negative bacteria (see Gram's stain), including s...

gramicidin

(Encyclopedia)gramicidin grămˌĭsīdˈən [key], antibiotic obtained from the bacterial species Bacillus brevis, which is found in soil. Gramicidin is particularly effective against gram-positive bacteria (see Gr...

van der Waals, Johannes Diderik

(Encyclopedia)van der Waals, Johannes Diderik yōhäˈnəs dēˈdərĭk vän dər väls [key], 1837–1923, Dutch physicist. It had been known for some time that the behavior of real gases differs from that of an i...

cgs system

(Encyclopedia)cgs system, system of units of measurement based on the metric system and having the centimeter of length, the gram of mass, and the second of time as its fundamental units. Other cgs units are the dy...

penicillin

(Encyclopedia)penicillin, any of a group of chemically similar substances obtained from molds of the genus Penicillium that were the first antibiotic agents to be used successfully in the treatment of bacterial inf...

vancomycin

(Encyclopedia)vancomycin vănˌkōmīˈsĭn [key], antibiotic resembling penicillin in the way it acts. It is derived from the bacterium Streptomyces orientalis, which was isolated from soil of India and Indonesia....

Brenner, Sydney

(Encyclopedia)Brenner, Sydney, 1927–2019, British molecular biologist, Ph.D. Oxford, 1954. He was director of the MRC Laboratory of Molecular Biology in Cambridge, England (1979–86), and director of the MRC Mol...

krypton

(Encyclopedia)krypton krĭpˈtŏn [key] [Gr.,=hidden], gaseous chemical element; symbol Kr; at. no. 36; at. wt. 83.798; m.p. −156.6℃; b.p. −152.3℃; density 3.73 grams per liter at STP; valence usually 0. Kr...