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Actinium
2009-07-09 17:04:18

Actinium is a radioactive chemical element. The symbol for Actinium is Ac and the atomic number is 89. Actinium was discovered in 1899 by French chemist André-Louis Debierne. It was the first non-primordial radioactive element to be isolated. Actinium is amongst a group of 15 similar elements within the periodic table that make up the actinoid series. This substance was also independently...

Word of the Day
vermicular
  • Like a worm in form or movement; vermiform; tortuous or sinuous; also, writhing or wriggling.
  • Like the track or trace of a worm; appearing as if worm-eaten; vermiculate.
  • Marked with fine, close-set, wavy or tortuous lines of color; vermiculated.
  • A form of rusticated masonry which is so wrought as to appear thickly indented with worm-tracks.
This word ultimately comes from the Latin 'vermis,' worm.
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