[医] 汗疱

Pompholyx \Pom"pho*lyx\, n. [L., fr. Gr. ? a bubble, the slag on
the surface of smelted ore, from ? a blister.]
1. (Old Chem.) Impure zinc oxide.

2. (Med.) A skin disease in which there is an eruption of
bull[ae], without inflammation or fever.

Zinc \Zinc\ (z[i^][ng]k), n. [G. zink, probably akin to zinn
tin: cf. F. zinc, from the German. Cf. {Tin}.] (Chem.)
An abundant element of the magnesium-cadmium group, extracted
principally from the minerals zinc blende, smithsonite,
calamine, and franklinite, as an easily fusible bluish white
metal, which is malleable, especially when heated. It is not
easily oxidized in moist air, and hence is used for sheeting,
coating galvanized iron, etc. It is used in making brass,
britannia, and other alloys, and is also largely consumed in
electric batteries. Symbol Zn. Atomic number 30. Atomic
weight 65.38. [Formerly written also {zink}.]

{Butter of zinc} (Old Chem.), zinc chloride, {ZnCl2}, a
deliquescent white waxy or oily substance.

{Oxide of zinc}. (Chem.) See {Zinc oxide}, below.

{Zinc amine} (Chem.), a white amorphous substance,
{Zn(NH2)2}, obtained by the action of ammonia on zinc
ethyl; -- called also {zinc amide}.

{Zinc amyle} (Chem.), a colorless, transparent liquid,
composed of zinc and amyle, which, when exposed to the
atmosphere, emits fumes, and absorbs oxygen with rapidity.


{Zinc blende} [cf. G. zinkblende] (Min.), a native zinc
sulphide. See {Blende}, n.
(a) .

{Zinc bloom} [cf. G. zinkblumen flowers of zinc, oxide of
zinc] (Min.), hydrous carbonate of zinc, usually occurring
in white earthy incrustations; -- called also
{hydrozincite}.

{Zinc ethyl} (Chem.), a colorless, transparent, poisonous
liquid, composed of zinc and ethyl, which takes fire
spontaneously on exposure to the atmosphere.

{Zinc green}, a green pigment consisting of zinc and cobalt
oxides; -- called also {Rinmann's green}.

{Zinc methyl} (Chem.), a colorless mobile liquid {Zn(CH3)2},
produced by the action of methyl iodide on a zinc sodium
alloy. It has a disagreeable odor, and is spontaneously
inflammable in the air. It has been of great importance in
the synthesis of organic compounds, and is the type of a
large series of similar compounds, as zinc ethyl, zinc
amyle, etc.

{Zinc oxide} (Chem.), the oxide of zinc, {ZnO}, forming a
light fluffy sublimate when zinc is burned; -- called also
{flowers of zinc}, {philosopher's wool}, {nihil album},
etc. The impure oxide produced by burning the metal,
roasting its ores, or in melting brass, is called also
{pompholyx}, and {tutty}.

{Zinc spinel} (Min.), a mineral, related to spinel,
consisting essentially of the oxides of zinc and
aluminium; gahnite.

{Zinc vitriol} (Chem.), zinc sulphate. See {White vitriol},
under {Vitriol}.

{Zinc white}, a white powder consisting of zinc oxide, used
as a pigment.