In vivo synthesis of europium selenide nanoparticles and related cytotoxicity evaluation of human cells.

See more Selenium products. Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. The number of electrons in each of Selenium's shells is 2, 8, 18, 6 and its electron configuration is [Ar] 3d¹⁰ 4s² 4p⁴. The selenium atom has a radius of 120 pm and a Van der Waals radius of 190 pm. Selenium is a non-metal with several allotropes: a black, vitreous form with an irregular crystal structure three red-colored forms with monoclinic crystal structures and a gray form with a hexagonal crystal structure, the most stable and dense form of the element. One of the most common uses for selenium is in glass production the red tint that it lends to glass neutralizes green or yellow tints from impurities in the glass materials. Selenium was discovered and first isolated by Jöns Jakob Berzelius and Johann Gottlieb Gahn in 1817. The origin of the name Selenium comes from the Greek word "Selênê," meaning moon.

See more Europium products. Europium (atomic symbol: Eu, atomic number: 63) is a Block F, Group 3, Period 6 element with an atomic radius of 151.964. The number of electrons in each of Europium's shells is 2, 8, 18, 25, 8, 2 and its electron configuration is [Xe]4f⁷ 6s². The europium atom has an atomic radius of 180 pm and a Van der Waals radius of 233 pm. Europium was discovered by Eugène-Anatole Demarçay in 1896, however, he did not isolate it until 1901. Europium was named after the continent of Europe. Europium is a member of the lanthanide or rare earth series of metals. In its elemental form, it has a silvery-white appearance but it is rarely found without oxide discoloration. Europium is found in many minerals including bastnasite, monazite, xenotime and loparite. It is not found in nature as a free element.