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refrigeration

(Encyclopedia)CE5 Compression system of refrigeration refrigeration, process for drawing heat from substances to lower their temperature, often for purposes of preservation. Refrigeration in its modern, portabl...

hotbed

(Encyclopedia)hotbed, low, glass-covered frame structure for starting tender plants. It differs from a cold frame only in that the soil is heated—either artificially as by underground electric wiring or steampipe...

diathermy

(Encyclopedia)diathermy dīˈəthûrˌmē [key], therapeutic measure used in medicine to generate heat in the body tissues. Electrodes and other instruments are used to transmit electric current to surface structur...

toxoid

(Encyclopedia)toxoid, protein toxin treated by heat or chemicals so that its poisonous property is destroyed but its capacity to stimulate the formation of toxin antibodies, or antitoxins, remains. Because toxoids ...

Richet, Charles Robert

(Encyclopedia)Richet, Charles Robert shärl rōbĕrˈ rēshāˈ [key], 1850–1935, French physiologist. From 1887 to 1927 he was professor at the Univ. of Paris. His special study was anaphylaxis, a term he used t...

Abbot, Charles Greeley

(Encyclopedia)Abbot, Charles Greeley, 1872–1973, American astrophysicist, b. Wilton, N.H. He was acting director in 1896 and director in 1907 of the astrophysical observatory of the Smithsonian Institution; he wa...

Stefan, Josef

(Encyclopedia)Stefan, Josef yōˈzĕf shtĕfˈän [key], 1835–93, Austrian physicist. At the Univ. of Vienna he became a professor of physics and later director of the Physical Institute. From his observations on...

Bermuda grass

(Encyclopedia)Bermuda grass, perennial pasture, lawn, and hay grass (Cynodon dactylon) of the family Poaceae (grass family), native to Africa and Asia and now common in warm regions of both hemispheres. It is the s...

activation energy

(Encyclopedia)CE5 Energy profile of an exothermic reaction: Although the total energy of the products is less than that of the reactants, the activation energy must be added to weaken or break existing bonds bef...

water, desalination of

(Encyclopedia)water, desalination of, process of removing soluble salts from water to render it suitable for drinking, irrigation, or industrial uses. The principal methods used for desalination include distillatio...