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Bosch, Carl

(Encyclopedia)Bosch, Carl, 1874–1940, German chemist and engineer, Ph.D. Univ. of Leipzig, 1898. In 1899, Bosch began working as a chemist for BASF, which merged with six other German chemical firms to become I. ...

density

(Encyclopedia)density, ratio of the mass of a substance to its volume, expressed, for example, in units of grams per cubic centimeter or pounds per cubic foot. The density of a pure substance varies little from sam...

caisson

(Encyclopedia)caisson kāˈsən, –sŏn [key] [Fr.,=big box], in engineering, a chamber, usually of steel but sometimes of wood or reinforced concrete, used in the construction of foundations or piers in or near a...

corns and calluses

(Encyclopedia)corns and calluses, thickenings of the outer layer of skin where there is irritation or constant pressure. Corns are cone-shaped with their points protruding into the dermis, or inner layer of skin. T...

Haber process

(Encyclopedia)Haber process häˈbər [key], commercial process for the synthesis of ammonia, NH3. Pure hydrogen and nitrogen gases are mixed in the appropriate proportion, heated to between 450℃ and 600℃, comp...

damp

(Encyclopedia)damp, in mining, any mixture of gases in an underground mine, especially oxygen-deficient or noxious gases. The term damp probably is derived from the German dampf, meaning fog or vapor. Several disti...

glaucoma

(Encyclopedia)glaucoma glôkōˈmə [key], ocular disorder characterized by pressure within the eyeball caused by an excessive amount of aqueous humor (the fluid substance filling the eyeball). This causes pressure...

boiler

(Encyclopedia)boiler, device for generating steam. It consists of two principal parts: the furnace, which provides heat, usually by burning a fuel, and the boiler proper, a device in which the heat changes water in...

hydraulic machine

(Encyclopedia)CE5 Hydraulic pressure: In any hydraulic device the pressure exerted by one piston is transmitted throughout the fluid. Since pressure equals force divided by area, a small force (F1) exerted on a ...

touch

(Encyclopedia)touch, tactile sensation received by the skin, enabling the organism to detect objects or substances in contact with the body. End organs (nerve endings) in the skin convey the impression to the brain...