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mordant

(Encyclopedia)mordant môrˈdənt [key] [Fr.,=biting], substance used in dyeing to fix certain dyes (mordant dyes) in cloth. Either the mordant (if it is colloidal) or a colloid produced by the mordant adheres to t...

anion

(Encyclopedia)anion ănˈīˌən [key], atom or group of atoms carrying a negative charge. The charge results because there are more electrons than protons in the anion. Anions can be formed from nonmetals by reduc...

perfluoroalkyl and polyfluoroalkyl substances

(Encyclopedia)perfluoroalkyl and polyfluoroalkyl substances (PFAS), a group of several thousand synthetic organic chemical compounds made up of a chain of carbon atoms bonded to fluorine atoms. PFAS, which resist w...

soapstone

(Encyclopedia)soapstone or steatite stēˈətīt [key], metamorphic rock of which the characteristic and usually chief mineral is talc, but which also contains varying parts of chlorite, mica, tremolite, quartz, ma...

beryl

(Encyclopedia)beryl bĕrˈĭl [key], mineral, a silicate of beryllium and aluminum, Be3Al2Si6O18, extremely hard, occurring in hexagonal crystals that may be of enormous size and are usually white, yellow, green, b...

cocoa-plum

(Encyclopedia)cocoa-plum, sweet but somewhat dry fruit of the evergreen tree Chrysobalanus icaco, of the family Chyrsobalanaceae. The fruits are eaten fresh and often made into preserves. An oil used for making can...

Ratdolt, Erhard

(Encyclopedia)Ratdolt, Erhard ĕrˈhärt räˈtôlt [key], 1442–1528, printer in Venice from 1476 to 1486 and in Augsburg from 1487 to 1522. A sheet showing specimens of his sizes and designs of type, dated 1486,...

child abuse

(Encyclopedia)child abuse, physical, sexual, or emotional maltreatment or neglect of children by parents, guardians, or others responsible for a child's welfare. Physical abuse is characterized by physical injury, ...

hydrogenation

(Encyclopedia)hydrogenation hīdrôjˈənāˌshən, hīˌdrəjənāˈshən [key], chemical reaction of a substance with molecular hydrogen, usually in the presence of a catalyst. A common hydrogenation is the harde...

injection

(Encyclopedia)injection, introduction of a fluid into the body, usually by means of a needle and syringe. The material injected may be a test substance (as in determining allergic sensitivity or immunity to a disea...