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iridium

(Encyclopedia)iridium ĭrĭdˈēəm [key], metallic chemical element; symbol Ir; at. no. 77; at. wt. 192.217; m.p. about 2,410℃; b.p. about 4,130℃; sp. gr. 22.55 at 20℃; valence +3 or +4. Iridium is a very ha...

ligand

(Encyclopedia)ligand lĭgˈənd [key], charged or uncharged molecule with one or more unshared pairs of electrons that can attach to a central metallic atom or ion to form an aggregate known as a complex ion (see c...

holmium

(Encyclopedia)holmium hōlˈmēəm [key] [Lat.,=Stockholm], metallic chemical element; symbol Ho; at. no. 67; at. wt. 164.93032; m.p. about 1,474℃; b.p. about 2,425℃; sp. gr. 8.78 at 25℃; valence +3. Holmium ...

thermite

(Encyclopedia)thermite [from Thermit, a trade name], mixture of powdered or granular aluminum metal and powdered iron oxide. When ignited it gives off large amounts of heat. In wartime it has been used in incendiar...

Cudahy

(Encyclopedia)Cudahy kŭdˈəhēˌ [key]. 1 City (2020 pop. 23,197), Los Angeles co., S Calif., a suburb of...

champlevé

(Encyclopedia)champlevé shäNləvāˈ [key], technique for the enamel decoration of metal objects. It was used by the Celts and Romans and employed by medieval metalworkers for jewelry and reliquaries until the 14...

fatigue, in engineering

(Encyclopedia)fatigue, in engineering, microscopic cracking of materials, especially metals, after repeated applications of stress. Fissures may be formed within pieces of metal during their manufacture when, while...

Weslaco

(Encyclopedia)Weslaco wĕsˈlĭkō [key], city (1990 pop. 21,877), Hidalgo co., extreme S Tex., in the irrigated region of the lower Rio Grande valley; inc. 1921. Cotton, citrus, and vegetables are grown, and there...

gallium

(Encyclopedia)gallium gălˈēəm [key], metallic chemical element; symbol Ga; at. no. 31; at. wt. 69.723; m.p. 29.78℃; b.p. 2,403℃; sp. gr. 5.904 at 29.6℃ (solid), 6.095 at 29.8℃ (liquid); valence +2 or +3...

ruthenium

(Encyclopedia)ruthenium ro͞othēˈnēəm [key], metallic chemical element; symbol Ru; at. no. 44; at. wt. 101.07; m.p. about 2,310℃; b.p. about 3,900℃; sp. gr. 12.41 at 20℃; valence commonly +2, +3, +4, +6, ...