thal·li·um /ˈθæliəm/
 稀金屬元素,鉈符號Ti,原子序81


 thal·li·um /ˈθælɪəm/ 名詞
 鉈


 Thal·li·um n.  Chem. A rare metallic element of the aluminium group found in some minerals, as certain pyrites, and also in the lead-chamber deposit in the manufacture of sulphuric acid. It is isolated as a heavy, soft, bluish white metal, easily oxidized in moist air, but preserved by keeping under water. Symbol Tl. Atomic weight 203.7.

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 thallium
      n : a soft gray malleable metallic element that resembles tin
          but discolors on exposure to air; it is highly toxic and
          is used in rodent and insect poisons; occurs in zinc
          blende and some iron ores [syn: Tl, atomic number 81]


 thallium
 Symbol: Tl
 Atomic number: 81
 Atomic weight: 204.3833
 Pure, unreacted thallium appears silvery-white and exhibits a metallic
 lustre. Upon reacting with air, it begins to turn bluish-grey and looks
 like lead. It is very malleable, and can be cut with a knife. There are
 two stable isotopes, and four radioisotopes, Tl-204 being the most stable
 with a half-life of 3.78 years. Thallium sulphate was used as a rodenticide.
 Thallium sulphine's conductivity changes with exposure to infrared light,
 this gives it a use in infrared detectors. Discovered by Sir William Crookes
 via spectroscopy. Its name comes from the Greek word thallos, which means
 green twig. Thallium and its compounds are toxic and can cause cancer.