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jelly and jam

(Encyclopedia)jelly and jam, gelatinous, sweet food prepared by preserving fresh fruits. Since most fresh fruits contain about 80% water and from 10% to 15% sugar, they are subject to fermentation. They may be pres...

acetylene

(Encyclopedia)acetylene ĕthˈīn [key], HC≡CH, a colorless gas. It melts at −80.8℃ and boils at −84.0℃. Offensive odors often noted in commercial acetylene are due to impurities. Acetylene forms explosiv...

van der Waals, Johannes Diderik

(Encyclopedia)van der Waals, Johannes Diderik yōhäˈnəs dēˈdərĭk vän dər väls [key], 1837–1923, Dutch physicist. It had been known for some time that the behavior of real gases differs from that of an i...

septic tank

(Encyclopedia)septic tank, underground sedimentation tank in which sewage is retained for a short period while it is decomposed and purified by bacterial action. The organic matter in the sewage settles to the bott...

phosphorescence

(Encyclopedia)phosphorescence fŏsˌfərĕsˈəns [key], luminescence produced by certain substances after absorbing radiant energy or other types of energy. Phosphorescence is distinguished from fluorescence in th...

phosphoric acid

(Encyclopedia)phosphoric acid, any one of three chemical compounds made up of phosphorus, oxygen, and hydrogen (see acids and bases). The most common, orthophosphoric acid, H3PO4, is usually simply called phosphori...

cathode-ray tube

(Encyclopedia)CE5 Cathode-ray tube cathode-ray tube (CRT), special-purpose electron tube in which electrons are accelerated by high-voltage anodes, formed into a beam by focusing electrodes, and projected towar...

caviar

(Encyclopedia)caviar or caviare kăvˈēär [key], the roe (eggs) of various species of sturgeon prepared as a piquant table delicacy. The ovaries of the fish are beaten to loosen the eggs, which are then freed fro...

ammonia

(Encyclopedia)ammonia, chemical compound, NH3, colorless gas that is about one half as dense as air at ordinary temperatures and pressures. It has a characteristic pungent, penetrating odor. Ammonia forms a minute ...

fuel

(Encyclopedia)fuel, material that can be burned or otherwise consumed to produce heat. The common fuels used in industry, transportation, and the home are burned in air. The carbon and hydrogen in fuel rapidly comb...