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rigor mortis

(Encyclopedia)rigor mortis rĭˈgər môrˈtĭs [key], rigidity of the body that occurs after death. The onset may vary from about 10 min to several hours or more after death, depending on the condition of the body...

vermilion

(Encyclopedia)vermilion, vivid red pigment of durable quality. It is a chemical compound of mercury and sulfur and is known as red sulfide of mercury; it was formerly obtained by grinding pure cinnabar but is now c...

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...

hafnium

(Encyclopedia)hafnium hăfˈnēəm [key], metallic chemical element; symbol Hf; at. no. 72; at. wt. 178.49; m.p. about 2,227℃; b.p. 4,602℃; sp. gr. 13.31 at 20℃; valence +4. Hafnium is a lustrous, ductile, si...

americium

(Encyclopedia)americium ămərĭˈshēəm [key], artificially produced radioactive chemical element; symbol Am; at. no. 95; mass no. of most stable isotope 243; m.p. about 1,175℃; b.p. about 2,600℃; sp. gr. 13....

micromechanics

(Encyclopedia)micromechanics, the combination of minuscule electrical and mechanical components in a single device less than 1 mm across, such as a valve or a motor. Although micromechanical production processes an...

mixture

(Encyclopedia)mixture, in chemistry, a physical combination of two or more pure substances (i.e., elements or compounds). A mixture is distinguished from a compound, which is formed by the chemical combination of t...

niobium

(Encyclopedia)niobium nīōˈbēəm [key], metallic chemical element; symbol Nb; at. no. 41; at. wt. 92.90638; m.p. about 2,468℃; b.p. 4,742℃; sp. gr. 8.57 at 20℃; valence +2, +3, +4, or +5. Niobium is a rare...

neptunium

(Encyclopedia)neptunium nĕpto͞oˈnēəm [key], radioactive chemical element; symbol Np; at. no. 93; mass number of most stable isotope 237; m.p. about 640℃; b.p. 3,902℃ (estimated); sp. gr. 20.25 at 20℃; va...

neon

(Encyclopedia)neon nēˈŏn [key] [Gr.,=new], gaseous chemical element; symbol Ne; at. no. 10; at. wt. 20.1797; m.p. −248.67℃; b.p. −246.048℃; density 0.8999 grams per liter at STP; valence 0. Neon is a col...