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MnO2

資料來源 : Webster's Revised Unabridged Dictionary (1913)

Black \Black\, a. [OE. blak, AS. bl[ae]c; akin to Icel. blakkr
   dark, swarthy, Sw. bl["a]ck ink, Dan. bl[ae]k, OHG. blach,
   LG. & D. blaken to burn with a black smoke. Not akin to AS.
   bl[=a]c, E. bleak pallid. ?98.]
   1. Destitute of light, or incapable of reflecting it; of the
      color of soot or coal; of the darkest or a very dark
      color, the opposite of white; characterized by such a
      color; as, black cloth; black hair or eyes.

            O night, with hue so black!           --Shak.

   2. In a less literal sense: Enveloped or shrouded in
      darkness; very dark or gloomy; as, a black night; the
      heavens black with clouds.

            I spy a black, suspicious, threatening cloud.
                                                  --Shak.

   3. Fig.: Dismal, gloomy, or forbidding, like darkness;
      destitute of moral light or goodness; atrociously wicked;
      cruel; mournful; calamitous; horrible. ``This day's black
      fate.'' ``Black villainy.'' ``Arise, black vengeance.''
      ``Black day.'' ``Black despair.'' --Shak.

   4. Expressing menace, or discontent; threatening; sullen;
      foreboding; as, to regard one with black looks.

   Note: Black is often used in self-explaining compound words;
         as, black-eyed, black-faced, black-haired,
         black-visaged.

   {Black act}, the English statute 9 George I, which makes it a
      felony to appear armed in any park or warren, etc., or to
      hunt or steal deer, etc., with the face blackened or
      disguised. Subsequent acts inflicting heavy penalties for
      malicious injuries to cattle and machinery have been
      called black acts.

   {Black angel} (Zo["o]l.), a fish of the West Indies and
      Florida ({Holacanthus tricolor}), with the head and tail
      yellow, and the middle of the body black.

   {Black antimony} (Chem.), the black sulphide of antimony,
      {Sb2S3}, used in pyrotechnics, etc.

   {Black bear} (Zo["o]l.), the common American bear ({Ursus
      Americanus}).

   {Black beast}. See {B[^e]te noire}.

   {Black beetle} (Zo["o]l.), the common large cockroach
      ({Blatta orientalis}).

   {Black and blue}, the dark color of a bruise in the flesh,
      which is accompanied with a mixture of blue. ``To pinch
      the slatterns black and blue.'' --Hudibras.

   {Black bonnet} (Zo["o]l.), the black-headed bunting ({Embriza
      Sch[oe]niclus}) of Europe.

   {Black canker}, a disease in turnips and other crops,
      produced by a species of caterpillar.

   {Black cat} (Zo["o]l.), the fisher, a quadruped of North
      America allied to the sable, but larger. See {Fisher}.

   {Black cattle}, any bovine cattle reared for slaughter, in
      distinction from dairy cattle. [Eng.]

   {Black cherry}. See under {Cherry}.

   {Black cockatoo} (Zo["o]l.), the palm cockatoo. See
      {Cockatoo}.

   {Black copper}. Same as {Melaconite}.

   {Black currant}. (Bot.) See {Currant}.

   {Black diamond}. (Min.) See {Carbonado}.

   {Black draught} (Med.), a cathartic medicine, composed of
      senna and magnesia.

   {Black drop} (Med.), vinegar of opium; a narcotic preparation
      consisting essentially of a solution of opium in vinegar.
      

   {Black earth}, mold; earth of a dark color. --Woodward.

   {Black flag}, the flag of a pirate, often bearing in white a
      skull and crossbones; a signal of defiance.

   {Black flea} (Zo["o]l.), a flea beetle ({Haltica nemorum})
      injurious to turnips.

   {Black flux}, a mixture of carbonate of potash and charcoal,
      obtained by deflagrating tartar with half its weight of
      niter. --Brande & C.

   {Black fly}. (Zo["o]l.)
      (a) In the United States, a small, venomous, two-winged
          fly of the genus {Simulium} of several species,
          exceedingly abundant and troublesome in the northern
          forests. The larv[ae] are aquatic.
      (b) A black plant louse, as the bean aphis ({A. fab[ae]}).
          

   {Black Forest} [a translation of G. Schwarzwald], a forest in
      Baden and W["u]rtemburg, in Germany; a part of the ancient
      Hercynian forest.

   {Black game}, or {Black grouse}. (Zo["o]l.) See {Blackcock},
      {Grouse}, and {Heath grouse}.

   {Black grass} (Bot.), a grasslike rush of the species {Juncus
      Gerardi}, growing on salt marshes, and making good hay.

   {Black gum} (Bot.), an American tree, the tupelo or
      pepperidge. See {Tupelo}.

   {Black Hamburg (grape)} (Bot.), a sweet and juicy variety of
      dark purple or ``black'' grape.

   {Black horse} (Zo["o]l.), a fish of the Mississippi valley
      ({Cycleptus elongatus}), of the sucker family; the
      Missouri sucker.

   {Black lemur} (Zo["o]l.), the {Lemurniger} of Madagascar; the
      {acoumbo} of the natives.

   {Black list}, a list of persons who are for some reason
      thought deserving of censure or punishment; -- esp. a list
      of persons stigmatized as insolvent or untrustworthy, made
      for the protection of tradesmen or employers. See
      {Blacklist}, v. t.

   {Black manganese} (Chem.), the black oxide of manganese,
      {MnO2}.

   {Black Maria}, the close wagon in which prisoners are carried
      to or from jail.

   {Black martin} (Zo["o]l.), the chimney swift. See {Swift}.

   {Black moss} (Bot.), the common so-called long moss of the
      southern United States. See {Tillandsia}.

   {Black oak}. See under {Oak}.

   {Black ocher}. See {Wad}.

   {Black pigment}, a very fine, light carbonaceous substance,
      or lampblack, prepared chiefly for the manufacture of
      printers' ink. It is obtained by burning common coal tar.
      

   {Black plate}, sheet iron before it is tinned. --Knight.

   {Black quarter}, malignant anthrax with engorgement of a
      shoulder or quarter, etc., as of an ox.

   {Black rat} (Zo["o]l.), one of the species of rats ({Mus
      rattus}), commonly infesting houses.

   {Black rent}. See {Blackmail}, n., 3.

   {Black rust}, a disease of wheat, in which a black, moist
      matter is deposited in the fissures of the grain.

   {Black sheep}, one in a family or company who is unlike the
      rest, and makes trouble.

   {Black silver}. (Min.) See under {Silver}.

   {Black and tan}, black mixed or spotted with tan color or
      reddish brown; -- used in describing certain breeds of
      dogs.

   {Black tea}. See under {Tea}.

   {Black tin} (Mining), tin ore (cassiterite), when dressed,
      stamped and washed, ready for smelting. It is in the form
      of a black powder, like fine sand. --Knight.

   {Black walnut}. See under {Walnut}.

   {Black warrior} (Zo["o]l.), an American hawk ({Buteo
      Harlani}).

   Syn: Dark; murky; pitchy; inky; somber; dusky; gloomy; swart;
        Cimmerian; ebon; atrocious.

Manganese \Man`ga*nese"\, n. [F. mangan[`e]se, It. manganese,
   sasso magnesio; prob. corrupted from L. magnes, because of
   its resemblance to the magnet. See {Magnet}, and cf.
   {Magnesia}.] (Chem.)
   An element obtained by reduction of its oxide, as a hard,
   grayish white metal, fusible with difficulty, but easily
   oxidized. Its ores occur abundantly in nature as the minerals
   pyrolusite, manganite, etc. Symbol Mn. Atomic weight 54.8.

   Note: An alloy of manganese with iron (called ferromanganese)
         is used to increase the density and hardness of steel.

   {Black oxide of manganese}, {Manganese dioxide or peroxide},
      or {Black manganese} (Chem.), a heavy black powder {MnO2},
      occurring native as the mineral pyrolusite, and valuable
      as a strong oxidizer; -- called also familiarly
      {manganese}. It colors glass violet, and is used as a
      decolorizer to remove the green tint of impure glass.

   {Manganese bronze}, an alloy made by adding from one to two
      per cent of manganese to the copper and zinc used in
      brass.
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