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hydrogen sulfide

(Encyclopedia)hydrogen sulfide, chemical compound, H2S, a colorless, extremely poisonous gas that has a very disagreeable odor, much like that of rotten eggs. It is slightly soluble in water and is soluble in carbo...

silage

(Encyclopedia)silage ĕnˈsəlĭj [key], succulent, moist feed made by storing a green crop in a silo. The crop most used for silage is corn; others are sorghum, sunflowers, legumes, and grass. In a sealed silo, ty...

placenta

(Encyclopedia)placenta pləsĕnˈtə [key] or afterbirth, organ that develops in the uterus during pregnancy. It is a unique characteristic of the higher (or placental) mammals. In humans it is a thick mass, about ...

glycolysis

(Encyclopedia)glycolysis glīkŏlˈĭsĭs [key], term given to the metabolic pathway utilized by most microorganisms (yeast and bacteria) and by all “higher” animals (including humans) for the degradation of gl...

nitrous oxide

(Encyclopedia)nitrous oxide or nitrogen (I) oxide, chemical compound, N2O, a colorless gas with a sweetish taste and odor. Its density is 1.977 grams per liter at STP. It is soluble in water, alcohol, ether, and ot...

thrombosis

(Encyclopedia)thrombosis thrŏmbōˈsĭs [key], obstruction of an artery or vein by a blood clot (thrombus). Arterial thrombosis is generally more serious because the supply of oxygen and nutrition to an area of th...

polycythemia

(Encyclopedia)polycythemia pŏlˌēsīthēˈmēə [key], condition characterized by an increase in the production of red blood cells, or erythrocytes, in the blood. Primary polycythemia, also called erythremia, or ...

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...

synthetic textile fibers

(Encyclopedia)synthetic textile fibers have revolutionized the textile industry. Such artificial fibers are usually long-chain polymers, produced industrially by the condensation of many small units. Orlon is the t...

Priestley, Joseph

(Encyclopedia)Priestley, Joseph, 1733–1804, English theologian and scientist. He prepared for the Presbyterian ministry and served several churches in England as pastor but gradually rejected orthodox Calvinism a...