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radar astronomy

(Encyclopedia)radar astronomy, application of radar to the determination of distances and planetary features within the solar system, such as rotation rates. A short burst of radio waves is transmitted in the direc...

Axelrod, Julius

(Encyclopedia)Axelrod, Julius ăkˈsəlrŏd [key], 1912–2004, American biochemist whose work was influential in the development of pharmaceuticals, b. New York City, grad. City College, N.Y. (B.S. 1933), New York...

gas

(Encyclopedia)gas, in physics, one of the three commonly recognized states of matter, the other two being solid and liquid. A substance in the gaseous state has neither definite shape nor definite volume. Like liqu...

hydrogen fluoride

(Encyclopedia)hydrogen fluoride, chemical compound, HF, a colorless, fuming liquid or colorless gas that boils at 19.54℃. It is miscible with water and is soluble in benzene, toluene, and concentrated sulfuric ac...

hydrology

(Encyclopedia)hydrology, study of water and its properties, including its distribution and movement in and through the land areas of the earth. The hydrologic cycle consists of the passage of water from the oceans ...

installment buying and selling

(Encyclopedia)installment buying and selling, buying and selling of goods on credit, with the stipulation that payments shall be made at specified intervals in set amounts. The goods may be used by the buyer before...

dysprosium

(Encyclopedia)dysprosium dĭsprōˈzēəm [key] [Gr.,=hard to get at], metallic chemical element; symbol Dy; at. no. 66; at. wt. 162.500; m.p. 1,412℃; b.p. 2,562℃; sp. gr. 8.54 at 25℃; valence+3. Dysprosium i...

einsteinium

(Encyclopedia)einsteinium īnˈstīˌnēəm, īnstīˈ– [key] [for Albert Einstein], artificially produced radioactive chemical element; symbol Es; at. no. 99; mass no. of most stable isotope 252; m.p. about 860�...

supersymmetry

(Encyclopedia)supersymmetry, in physics, theory concerning the relationship of the elementary particles called boson to those known as fermions, and vice versa, and linking the four fundamental forces. In supersymm...

pewter

(Encyclopedia)pewter, any of a number of ductile, silver-white alloys consisting principally of tin. The properties vary with the percentage of tin and the nature of the added materials. Lead, when added, imparts a...