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bark, in botany

(Encyclopedia)bark, outer covering of the stem of woody plants, composed of waterproof cork cells protecting a layer of food-conducting tissue—the phloem or inner bark (also called bast). As the woody stem increa...

Bakelite

(Encyclopedia)Bakelite bāˈkəlīt [key] [for its inventor, L. H. Baekeland], synthetic thermosetting resin. It has been widely used both alone, to form whole objects, and in combination with other materials, as a...

polymer

(Encyclopedia)CE5 A. Addition polymerization: Two ethylene molecules, C2H4, combine to form two links in the polyethylene chain molecule (C2H4)n. B. Condensation polymerization: Two glycine molecules, NH2CH2COOH...

brain stem

(Encyclopedia)brain stem, lower part of the brain, adjoining and structurally continuous with the spinal cord. The upper segment of the human brain stem, the pons, contains nerve fibers that connect the two halves ...

Manila hemp

(Encyclopedia)Manila hemp, the most important of the cordage fibers. It is obtained chiefly from the Manila hemp plant (Musa textilis) of the family Musaceae (banana family). It is grown mainly in its native Philip...

Orlon

(Encyclopedia)Orlon, trademark for an acrylic fiber available in filaments (long single strands) or staples (bundles of short fibers). Orlon is resistant to sunlight and atmospheric gases, which makes it ideal for ...

composition board

(Encyclopedia)composition board, wood product produced in the form of a board or sheet, formed of cellulose fibers or particles derived from wood or other sources, and used principally as a building material. The o...

flax

(Encyclopedia)flax, common name for members of the Linaceae, a family of annual herbs, especially members of the genus Linum, and for the fiber obtained from such plants. The flax of commerce (several varieties of ...

composite material

(Encyclopedia)composite material or composite, any material made from at least two discrete substances, such as concrete. Many materials are produced as composites, such as the fiberglass-reinforced plastics used f...

boll weevil

(Encyclopedia)boll weevil or cotton boll weevil bōl [key], cotton-eating weevil, or snout beetle, Anthonomus grandis. Probably of Mexican or Central American origin, it appeared in Texas about 1892 and spread to m...