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McGraw Hill Financial, Inc. is an American publicly traded corporation headquartered in Rockefeller Center in New York City. Its primary areas of business are financial, publishing, and business services.
A chemical element, symbol U, atomic number 92, atomic weight 238.03. The melting point is 1132°C (2070°F) and the boiling point is 3818°C (6904°F). Uranium is one of the actinide series.
Industry:Science
A chemical element, Tc, atomic number 43, discovered by Carlo Perrier and Emilio Segrè in 1937. They separated and isolated it from molybdenum (Mo; atomic number 42), which had been bombarded with deuterons in a cyclotron. Technetium does not occur naturally.
Industry:Science
A chemical element, Te, atomic number 52, and atomic weight 127.60. There are eight stable isotopes of natural tellurium. Tellurium makes up approximately 10<sup>−9</sup> % of the Earth's igneous rock. It is found as the free element, sometimes associated with selenium. It is more often found as the telluride sylvanite (graphic tellurium), nagyagite (black tellurium), hessite, tetradymite, altaite, coloradoite, and other silver-gold tellurides, as well as the oxide, tellurium ocher.
Industry:Science
A chemical element, Th, atomic number 90. Thorium is a member of the actinide series of elements. It is radioactive with a half-life of about 1.4 × 10<sup>10</sup> years.
Industry:Science
A chemical element, Ti, atomic number 22, and atomic weight 47.90. It occurs in the fourth group of the periodic table, and its chemistry shows many similarities to that of silicon and zirconium. On the other hand, as a first-row transition element, titanium has an aqueous solution chemistry, especially of the lower oxidation states, showing some resemblances to that of vanadium and chromium.
Industry:Science
A chemical element, TI, atomic number 81, relative atomic weight of 204.37. The valence electron notation corresponding to its ground state term is 6s<sup>2</sup>6<i>p</i><sup>1</sup>, which accounts for the maximum oxidation state of III in its compounds. Compounds of oxidation state I and apparent oxidation state II are also known.
Industry:Science
A chemical element, Tm, atomic number 69, atomic weight 168.934. It is a rare metallic element belonging to the rare-earth group. The stable isotope <sup>169</sup>Tm makes up 100% of the naturally occurring element.
Industry:Science
A chemical element, V, with atomic number 23. Natural deposits contain two isotopes, <sup>50</sup>V (0.24%), which is weakly radioactive, and <sup>51</sup>V (99.76%). Commercially important as an oxidation catalyst, vanadium also is used in the production of alloy steel and ceramics and as a colorizing agent. Studies have demonstrated the biological occurrence of vanadium, especially in marine species; in mammals, vanadium has a pronounced effect on heart muscle contraction and renal function.
Industry:Science
A chemical element, W, atomic number 74, and atomic weight 183.85. Naturally occurring tungsten consists of five stable isotopes having the following mass numbers and relative abundances: 180 (0.14%), 182 (26.4%), 183 (14.4%), 184 (30.6%), and 186 (28.4%). Twelve radioactive isotopes ranging from 173 to 189 also have been characterized.
Industry:Science
A chemical element, Xe, atomic number 54. It is a member of the family of noble gases, group 18 in the periodic table. Xenon is colorless, odorless, and tasteless; it is a gas under ordinary conditions (see <b>table</b>).
Industry:Science
