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pesticide

(Encyclopedia)pesticide, biological, physical, or chemical agent used to kill plants or animals that are harmful to people; in practice, the term pesticide is often applied only to chemical agents. Various pesticid...

Euler-Chelpin, Hans Karl August Simon von

(Encyclopedia)Euler-Chelpin, Hans Karl August Simon von, 1873–1964, Swedish biochemist, b. Germany, Ph.D. Univ. of Berlin, 1895. He spent his entire career at Stockholm Univ., first as professor and later as dire...

alkyne

(Encyclopedia)CE5 Alkynes alkyne ălˈkīn [key], any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon triple bonds (see chemical bond). Alkynes with one triple bond have t...

Jabir

(Encyclopedia)Jabir jēˈbər [key], fl. 8th cent., Arab alchemist and physician, originally named Jabir ibn Hayyan. He is believed to have lived at Kufa and at Baghdad. A great number of works on alchemy, many of ...

Schirra, Wally

(Encyclopedia)Schirra, Wally, (Walter Marty Schirra, Jr.), 1923–2007, the only American astronaut to fly in all of NASA's first three manned spaceflight programs, b. Hackensack, N.J., grad. U.S. Naval Academy (19...

Bologna, Giovanni

(Encyclopedia)Bologna, Giovanni, or Giambologna jōvänˈnē bōlōˈnyä, jämˌbōlōˈnyä [key], 1524–1608, Flemish sculptor, whose real name was Jean Bologne or Boulogne. Though born in Douai, France, he tra...

gold

(Encyclopedia)gold, metallic chemical element; symbol Au [Lat. aurum=shining dawn]; at. no. 79; at. wt. 196.96657; m.p. 1,064.43℃; b.p. 2,808℃; sp. gr. 19.32 at 20℃; valence +1 or +3. Gold is very ductile and...

Fourcroy, Antoine François, comte de

(Encyclopedia)Fourcroy, Antoine François, comte de äNtwänˈ fräNswäˈ kôNt də fo͞orkrwäˈ [key], 1755–1809, French chemist. He was a pioneer in animal and plant chemistry and collaborated with Lavoisier ...

potassium hydroxide

(Encyclopedia)potassium hydroxide, chemical compound with formula KOH. Pure potassium hydroxide forms white, deliquescent crystals. For commercial and laboratory use it is usually in the form of white pellets. A st...

Norrish, Ronald George Wreyford

(Encyclopedia)Norrish, Ronald George Wreyford, 1897–1978, British chemist, Ph.D. Cambridge, 1925. He joined the faculty at Cambridge in 1925 and was a professor there until he retired in 1965. Norrish was awarded...