Effect of Stone Composition on the Outcomes of Semi-Rigid Ureteroscopy Using Holmium: Yttrium-Aluminum-Garnet Laser or Pneumatic Lithotripsy.

See more Holmium products. Holmium (atomic symbol: Ho, atomic number: 67) is a Block F, Group 3, Period 6 element with an atomic radius of 164.93032. The number of electrons in each of Holmium's shells is [2, 8, 18, 29, 8, 2] and its electron configuration is [Xe] 4f¹¹ 6s². The holmium atom has a radius of 176 pm and its Covalent radius is 192±7 pm. Holmium was first discovered by Marc Delafontaine in 1878. In its elemental form, holmium has a silvery white appearance. It is relatively soft and malleable. It is stable in dry air at room temperature but rapidly oxidizes at elevated temperatures and in moist air. Holmium has unusual magnetic properties. Its name is derived from the Latin word Holmia meaning Stockholm.

See more Aluminum products. Aluminum (or Aluminium) (atomic symbol: Al, atomic number: 13) is a Block P, Group 13, Period 3 element with an atomic weight of 26.9815386. It is the third most abundant element in the earth's crust and the most abundant metallic element. Aluminum's name is derived from alumina, the mineral from which Sir Humphrey Davy attempted to refine it from in 1812. Aluminum was first predicted by Antoine Lavoisier 1787 and first isolated by Hans Christian Øersted in 1825. Aluminum is a silvery gray metal that possesses many desirable characteristics. It is light, nonmagnetic and non-sparking. It stands second among metals in the scale of malleability, and sixth in ductility. It is extensively used in many industrial applications where a strong, light, easily constructed material is needed. Although it has only 60% of the electrical conductivity of copper, it is used in electrical transmission lines because of its light weight. Pure aluminum is soft and lacks strength, but alloyed with small amounts of copper, magnesium, silicon, manganese, or other elements, it imparts a variety of useful properties.

See more Yttrium products. Yttrium (atomic symbol: Y, atomic number: 39) is a Block D, Group 3, Period 5 element with an atomic weight of 88.90585. The number of electrons in each of yttrium's shells is [2, 8, 18, 9, 2] and its electron configuration is [Kr] 4d¹ 5s². The yttrium atom has a radius of 180 pm and a Van der Waals radius of 219 pm. Yttrium was discovered by Johann Gadolin in 1794 and first isolated by Carl Gustav Mosander in 1840. In its elemental form, Yttrium has a silvery white metallic appearance. Yttrium has the highest thermodynamic affinity for oxygen of any element. Yttrium is not found in nature as a free element and is almost always found combined with the lanthanides in rare earth minerals. While not part of the rare earth series, it resembles the heavy rare earths which are sometimes referred to as the "yttrics" for this reason. Another unique characteristic derives from its ability to form crystals with useful properties. The name yttrium originated from a Swedish village near Vaxholm called Yttbery where it was discovered.