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International Union of Pure and Applied Chemistry

(Encyclopedia)International Union of Pure and Applied Chemistry (IUPAC), an international organization est. 1919 to advance the chemical sciences and contribute to the application of chemistry to the service of hum...

cytochrome

(Encyclopedia)cytochrome sīˈtəkrōmˌ [key], protein containing heme (see coenzyme) that participates in the phase of biochemical respiration called oxidative phosphorylation. Cytochromes act as carriers of hydr...

manganese

(Encyclopedia)manganese măngˈgənēs, mănˈ– [key] [Lat.,=magnet], metallic chemical element; symbol Mn; at. no. 25; at. wt. 54.93805; m.p. about 1,244℃; b.p. about 1,962℃; sp. gr. 7.2 to 7.45, depending o...

promethium

(Encyclopedia)promethium prōmēˈthēəm [key], artificially produced radioactive chemical element; symbol Pm; at. no. 61; mass no. of most stable isotope 145; m.p. 1,042℃; b.p. 3,000℃ (estimated); sp. gr. unk...

aldosterone

(Encyclopedia)aldosterone ălˌdōstĭrōnˈ [key], steroid secreted by the cortex of the adrenal gland. It is the most potent hormone regulating the body's electrolyte balance. Aldosterone acts directly on the kid...

cyanide process

(Encyclopedia)cyanide process or cyanidation, method for extracting gold from its ore. The ore is first finely ground and may be concentrated by flotation; if it contains certain impurities, it may be roasted. It i...

Svedberg, Theodor

(Encyclopedia)Svedberg, Theodor or The tāˈōdôr svādˈbĕryə, tā [key], 1884–1971, Swedish chemist. He was professor of physical chemistry from 1912 to 1949 at the Univ. of Uppsala. For his fundamental rese...

Werner, Alfred

(Encyclopedia)Werner, Alfred, 1866–1919, French-born Swiss chemist, Ph.D. Univ. of Zürich, 1890. Werner was a professor at the Univ. of Zürich from 1893 until his death in 1919. He was awarded the Nobel Prize i...

isomorphism

(Encyclopedia)isomorphism īˌsəmôrˈfĭzəm [key], of minerals, similarity of crystal structure between two or more distinct substances. Sodium nitrate and calcium sulfate are isomorphous, as are the sulfates of...

anion

(Encyclopedia)anion ănˈīˌən [key], atom or group of atoms carrying a negative charge. The charge results because there are more electrons than protons in the anion. Anions can be formed from nonmetals by reduc...

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