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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...

smart card

(Encyclopedia)smart card, small device that resembles a credit card but contains an embedded microprocessor to store and process information. Magnetic-stripe cards, which store a very small amount of information (m...

sickle cell disease

(Encyclopedia)sickle cell disease or sickle cell anemia, inherited disorder of the blood in which the oxygen-carrying hemoglobin pigment in erythrocytes (red blood cells) is abnormal. This “hemoglobin-S” crysta...

particle accelerator

(Encyclopedia)CE5 Linear accelerator (LINAC) CE5 Cyclotron: As the charged particles move faster, they spiral out to the edge of the Ds. particle accelerator, apparatus used in nuclear physics to produce bea...

stove

(Encyclopedia)stove, device used for heating or for cooking food. The stove was long regarded as a cooking device supplementary to the fireplace, near which it stood; its stovepipe led into the fireplace chimney. I...

television

(Encyclopedia)CE5 Video transmission and reception of color and black-and-white television: The camera lens focuses collected light rays into mirrors, which separate the image into its three primary color compon...

helium

(Encyclopedia)helium hēˈlēəm [key], gaseous chemical element; symbol He; at. no. 2; at. wt. 4.0026; m.p. below −272℃ at 26 atmospheres pressure; b.p. −268.934℃ at 1 atmosphere pressure; density 0.1785 g...

electricity

(Encyclopedia)CE5 Electrical and radio symbols electricity, class of phenomena arising from the existence of charge. The basic unit of charge is that on the proton or electron—the proton's charge is designate...

observatory

(Encyclopedia)observatory, scientific facility especially equipped to detect and record naturally occurring scientific phenomena. Although geological and meteorological observatories exist, the term is generally ap...

credit card

(Encyclopedia)credit card, device used to obtain consumer credit at the time of purchasing an article or service. Credit cards may be issued by a business, such as a department store or an oil company, to make it e...