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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...

Ashkin, Arthur

(Encyclopedia)Ashkin, Arthur, 1922–2020, American physicist, b. Brooklyn, N.Y., Ph.D. Cornell, 1952. Ashkin worked for four decades at Bell Laboratories, retiring in 1992. Ashkin researched microwaves, nonlinear ...

ACE inhibitor

(Encyclopedia)ACE inhibitor ănˌjēōtĕnˈsĭn [key], drug used to reduce elevated blood pressure (see hypertension), to treat congestive heart failure, and to alleviate strain on hea...

welding

(Encyclopedia)welding, process for joining separate pieces of metal in a continuous metallic bond. Cold-pressure welding is accomplished by the application of high pressure at room temperature; forge welding (forgi...

bladder, urinary

(Encyclopedia)bladder, urinary, muscular sac located in the pelvis that stores urine and contracts to expel it from the body. Urine enters the bladder from the kidneys through the ureters and is discharged from the...

die-casting

(Encyclopedia)die-casting, process by which molten metal is forced by a plunger or compressed air into a metallic die and the pressure maintained until the metal has solidified. Die castings are accurate, are sharp...

absorption

(Encyclopedia)absorption [Lat.,=sucking from], taking of molecules of one substance directly into another substance. It is contrasted with adsorption, in which the molecules adhere only to the surface of the second...

tallow

(Encyclopedia)tallow, solid fat extracted from the tissues and fatty deposits of animals, especially from suet (the fat of cattle and sheep). Pure tallow is white, odorless and tasteless; it consists chiefly of tri...

sciatica

(Encyclopedia)sciatica sīătˈĭkə [key], severe pain in the leg along the sciatic nerve and its branches. It may be caused by injury or pressure to the base of the nerve in the lower back, or by metabolic, toxic...

Pfeffer, Wilhelm

(Encyclopedia)Pfeffer, Wilhelm vĭlˈhĕlm pfĕˈfər [key], 1845–1920, German plant physiologist. He was professor of botany successively at the universities of Bonn, Basel, Tübingen, and Leipzig (from 1887). W...