Wikipedia:Main Page history/2018 March 5
From today's featured articleThorium is a chemical element with symbol Th and atomic number 90. A reactive actinide metal, its chemistry is dominated by the +4 oxidation state; it is silvery and tarnishes black in air, forming the dioxide. It is malleable and moderately hard, with a high melting point. Its most stable isotope, 232Th, is weakly radioactive with a half-life of 14.05 billion years, roughly the age of the universe: it decays very slowly to stable lead. Thorium and uranium are the only two significantly radioactive primordial elements. Thorium is chiefly refined from monazite sands as a byproduct of extracting rare earth metals. It was discovered in 1829 by the Norwegian mineralogist Morten Thrane Esmark and identified by the Swedish chemist Jöns Jacob Berzelius, who named it after Thor, the Norse god of thunder. Applications were found for the element in the 19th century, but after its radioactivity was discovered in the early 20th century, its use significantly declined. Thorium has been suggested as a replacement for uranium in nuclear reactors. (Full article...)
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On this day...March 5: Learn From Lei Feng Day in China
Gerardus Mercator (b. 1512) · Marietta Piccolomini (b. 1834) · Lena Baker (d. 1945) |
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The 70th Academy Awards ceremony, organized by the Academy of Motion Picture Arts and Sciences (AMPAS), took place on March 23, 1998, at the Shrine Auditorium in Los Angeles. During the ceremony, AMPAS presented Academy Awards (commonly referred to as Oscars) in 24 categories honoring films released in 1997. The ceremony, televised in the United States by ABC, was produced by Gil Cates and directed by Louis J. Horvitz. Actor Billy Crystal hosted for the fifth time, having last emceed the previous year's ceremony. Titanic received a record-tying 14 nominations and also won a record-tying eleven awards including Best Picture and Best Director for James Cameron (pictured). The telecast garnered more than 57 million viewers in the United States, making it the most watched Oscars broadcast in history. (Full list...)
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A ten Canadian dollar note, dated 1935. The first note of the 1935 issue by the Bank of Montreal, it depicts J. Dodds and C.B. Gordon with their signatures. The building on the reverse, then the Toronto branch of the Bank, is now part of the Hockey Hall of Fame. For more than a century, chartered banks were allowed to issue banknotes for domestic use. After the Bank of Canada was established in 1934, it took over the federal issuance of notes; chartered banks were prohibited from issuing their own currency in 1944. Banknote: Bank of Montreal (image courtesy of the National Numismatic Collection, National Museum of American History)
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