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iodoform

(Encyclopedia)iodoform īōˈdəfôrmˌ [key], CHI3, yellow crystalline solid that has a penetrating odor. It melts at 119℃ and is insoluble in water but soluble in ether or ethanol. Iodoform was formerly used as...

thyroid gland

(Encyclopedia)CE5 Thyroid gland thyroid gland, endocrine gland, situated in the neck, that secretes hormones necessary for growth and proper metabolism. It consists of two lobes connected by a narrow segment ca...

Coblentz, William Weber

(Encyclopedia)Coblentz, William Weber kōˈblĕnts [key], 1873–1962, American physicist, b. North Lima, Ohio, grad. Case School of Applied Science (B.S., 1900) and Cornell (Ph.D., 1903). From 1905 to 1945 he was ...

thyrotropin

(Encyclopedia)thyrotropin thīˌrätrōˈpĭn [key] or thyroid-stimulating hormone (TSH), hormone released by the anterior pituitary gland that stimulates the thyroid gland to release thyroxine. The release of thyr...

ash, in chemistry

(Encyclopedia)ash, in chemistry, solid residue of combustion. The chemical composition of an ash depends on that of the substance burned. Wood ash contains metal carbonates (e.g., potassium carbonate) and oxides fo...

Thénard, Louis Jacques

(Encyclopedia)Thénard, Louis Jacques lwē zhäk tānärˈ [key], 1777–1857, French chemist. He became professor at the Collège de France (1802), dean of the Faculty of Sciences, Paris (1821), chancellor of the ...

nonmetal

(Encyclopedia)nonmetal, chemical element possessing certain properties by which it is distinguished from a metal. In general, this distinction is drawn on the basis that a nonmetal tends to accept electrons and for...

radioactive isotope

(Encyclopedia)radioactive isotope or radioisotope, natural or artificially created isotope of a chemical element having an unstable nucleus that decays, emitting alpha, beta, or gamma rays until stability is reache...

axolotl

(Encyclopedia)axolotl ăkˈsəlŏtˌəl [key], a salamander, Ambystoma mexicanum, found in certain lakes in the region of Mexico City, which reaches reproductive maturity without losing its larval characteristics. ...

radiology

(Encyclopedia)radiology, branch of medicine specializing in the use of X rays, gamma rays, radioactive isotopes, and other forms of radiation in the diagnosis and treatment of disease. X ray machines and fluoroscop...

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