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acetaldehyde

(Encyclopedia)acetaldehyde ĕthˈənălˌ [key], CH3CHO, colorless liquid aldehyde, sometimes simply called aldehyde. It melts at −123℃, boils at 20.8℃, and is soluble in water and ethanol. It is formed by th...

antisense

(Encyclopedia)antisense, DNA or RNA manipulated in a laboratory so that its components (nucleotides) form a complementary copy of normal, or “sense,” messenger RNA (mRNA; see nucleic acid). Antisense techniques...

colchicine

(Encyclopedia)colchicine kŏlˈchəsēnˌ [key], alkaloid extracted from plants of the genus Colchicum and especially from the corms of the autumn crocus, Colchicum autumnale (see meadow saffron). The metabolic eff...

phosgene

(Encyclopedia)phosgene fŏsˈjēn [key], colorless poison gas, first used during World War I by the Germans (1915). When dispersed in air, the gas has the odor of new-mowed hay. The gas is highly toxic; when inhale...

printed circuit

(Encyclopedia)printed circuit, electric circuit in which the conducting paths connecting circuit components are affixed to a flat, insulating base board. The base is typically of plastic, glass, ceramic, or some ot...

Trail

(Encyclopedia)Trail, city (1991 pop. 7,919), SE British Columbia, Canada, on the Columbia River just N of the Wash. border. It is a metal-smelting center for a mining area that produces lead, zinc, silver, and gold...

ribosome

(Encyclopedia)ribosome: see cell; nucleic acid. ...

aqua fortis

(Encyclopedia)aqua fortis äkˈwə fôrˈtĭs [key]: see nitric acid. ...

methyl salicylate

(Encyclopedia)methyl salicylate səlĭsˈəlātˌ [key], methyl ester of salicylic acid. ...

Heiberg, Johan Ludvig

(Encyclopedia)Heiberg, Johan Ludvig yōhănˈ lo͞oᵺˈvē hīˈbâr [key], 1791–1860, Danish writer, director of the National Theater. In the play Christmas Fun and New Year's Jesting (1817), he satirized leadi...