Ruthenium is a chemical element with the symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group of the periodic table. Like the other metals of the platinum group, ruthenium is inert to most other chemicals. Russian-born scientist of Baltic-German ancestry Karl Ernst Claus discovered the element in 1844 at Kazan State University and named ruthenium in honor of Russia. Ruthenium is found as a minor component of platinum ores. Most ruthenium produced is used in thick-film resistors. A minor application for ruthenium is as a chemistry catalyst. A new application of ruthenium is as the capping layer for extreme ultraviolet photomasks. Ruthenium is found in ores with the other platinum group metals in the Ural Mountains and in North and South America. Small but commercially important quantities are found in pentlandite extracted from Sudbury, Ontario and in pyroxenite deposits in South Africa. Ruthenium, a polyvalent hard white metal, is a member of the platinum group and is in group 8 of the periodic table: Whereas all other group 8 elements have two electrons in the outermost shell, in ruthenium, the outermost shell has only one electron.
This anomaly is observed in the neighboring metals niobium and rhodium. Ruthenium does not tarnish at ambient conditions. Ruthenium dissolves in fused alkalis to give ruthenates, is not attacked by acids but is attacked by halogens at high temperatures. Indeed, ruthenium is most attacked by oxidizing agents. Small amounts of ruthenium can increase the hardness of palladium; the corrosion resistance of titanium is increased markedly by the addition of a small amount of ruthenium. The metal can be plated by thermal decomposition. A ruthenium-molybdenum alloy is known to be superconductive at temperatures below 10.6 K. Ruthenium is the last of the 4d transition metals that can assume the group oxidation state +8, then it is less stable there than the heavier congener osmium: this is the first group from the left of the table where the second and third-row transition metals display notable differences in chemical behavior. Like iron but unlike osmium, ruthenium can form aqueous cations in its lower oxidation states of +2 and +3.
Ruthenium is the first in a downward trend in the melting and boiling points and atomization enthalpy in the 4d transition metals after the maximum seen at molybdenum, because the 4d subshell is more than half full and the electrons are contributing less to metallic bonding. Unlike the lighter congener iron, ruthenium is paramagnetic at room temperature, as iron is above its Curie point; the reduction potentials in acidic aqueous solution for some common ruthenium ions are shown below: Naturally occurring ruthenium is composed of seven stable isotopes. Additionally, 34 radioactive isotopes have been discovered. Of these radioisotopes, the most stable are 106Ru with a half-life of 373.59 days, 103Ru with a half-life of 39.26 days and 97Ru with a half-life of 2.9 days. Fifteen other radioisotopes have been characterized with atomic weights ranging from 89.93 u to 114.928 u. Most of these have half-lives that are less than five minutes except 105Ru; the primary decay mode before the most abundant isotope, 102Ru, is electron capture and the primary mode after is beta emission.
The primary decay product before 102Ru is the primary decay product after is rhodium. As the 74th most abundant element in Earth's crust, ruthenium is rare, found in about 100 parts per trillion; this element is found in ores with the other platinum group metals in the Ural Mountains and in North and South America. Small but commercially important quantities are found in pentlandite extracted from Sudbury, Canada, in pyroxenite deposits in South Africa; the native form of ruthenium is a rare mineral. 30 tonnes of ruthenium are mined each year with world reserves estimated at 5,000 tonnes. The composition of the mined platinum group metal mixtures varies depending on the geochemical formation. For example, the PGMs mined in South Africa contain on average 11% ruthenium while the PGMs mined in the former USSR contain only 2%. Ruthenium and iridium are considered the minor platinum group metals. Ruthenium, like the other platinum group metals, is obtained commercially as a by-product from nickel, copper, platinum metals ore processing.
During electrorefining of copper and nickel, noble metals such as silver and the platinum group metals precipitate as anode mud, the feedstock for the extraction. The metals are converted to ionized solutes by any of several methods, depending on the composition of the feedstock. One representative method is fusion with sodium peroxide followed by dissolution in aqua regia, solution in a mixture of chlorine with hydrochloric acid. Osmium, ruthenium and iridium are insoluble in aqua regia and precipitate, leaving the other metals in solution. Rhodium is separated from the residue by treatment with molten sodium bisulfate; the insoluble residue, containing Ru, Os, Ir is treated with sodium o
Philippe Honoré is a French violinist, a regular recitalist in France and the United Kingdom. He was appointed Violin Professor at the Royal Academy of Music in London in September 2012, he has performed in broadcast recitals on French radio and television. Honoré divides his busy schedule between solo work, chamber music, collaboration with leading orchestras, he was a principal player with the Philharmonia Orchestra. After receiving top honours from the Paris Conservatoire and the Royal Academy of Music in London, he was made a Laureat of the Yehudi Menuhin Foundation in France in 1992, he was awarded an Honorary Associateship by the Royal Academy of Music in 2001. Honoré is a founder member of the Mobius Ensemble; as such, he has appeared in some of the most prestigious venues abroad and in the UK. He has appeared as a soloist performing Beethoven, Mozart and Vivaldi concerti, as well as Ravel's Tzigane. Honoré appears as guest leader with some of the UK's best orchestras, he has made numerous chamber music recordings.
His solo violin performances on the Decca album An Equal Music are featured on both Classic FM and Radio 3. The novel of that name by the author Vikram Seth was dedicated to him. Honoré's collaboration with the composer Alec Roth over a recent four-year project earned him great critical acclaim; the performances took place at the Salisbury and Lichfield Festivals. BBC Radio 3 recorded and broadcast these annual concerts, in which, in addition to the world premières of Roth's work, Honoré played solo Bach and Ysaÿe sonatas; the Times described his account of Roth's solo work in 2007 as “magically played”. A studio recording by Honoré of Roth's Ponticelli for solo violin was released by Signum records in November 2011. Honoré gave a performance of the entirety of this four-year-long project at the Music and Beyond Festival in Ottawa in July 2012; the series of these four concerts including Songs In Time Of War, The Traveller, the Seven Elements Suite was reviewed by the Wordpress Music and Beyond blog, which descrobed Honoré as both a violin virtuoso and a super violinist and the performances were referred to as spine-tingling.
Honoré's work with the Mobius Ensemble was awarded favourable reviews. Honoré's violin is an Eberle, made in 1786 in Naples; the Telegraph Alison Nicholls and Philippe Honoré Violin and Harp Duo Signum Records The Telegraph Philippe Honoré official website
Robert David Mariani is an American lawyer and a United States District Judge of the United States District Court for the Middle District of Pennsylvania. Born in Scranton, Mariani earned an Artium Baccalaureus degree in 1972 from Villanova University and a Juris Doctor in 1976 from Syracuse University College of Law. Robert Mariani was married to Sallyann Price until her death in 2008, they have three children together, Robert Jr. Christine and Jeanne-Michele. Out of law school, Mariani worked for three years at a Scranton law firm, he worked as a partner at a Scranton law firm from 1979 until 1993. From 1993 until his confirmation, Mariani was a lawyer in sole private practice in Scranton, specializing in labor and employment law. On December 1, 2010, President Obama nominated Mariani to a vacant judicial seat on the United States District Court for the Middle District of Pennsylvania, held by Judge James Martin Munley, who took senior status in January 2009. Mariani never received a Judiciary Committee hearing before the end of 2010, his nomination lapsed at the end of the year.
Obama renominated Mariani on January 5, 2011. On July 21, 2011, the Senate Judiciary Committee reported his nomination to the Senate floor and he was confirmed by the full Senate on October 19, 2011 by a vote of 82–17, he received his commission that same day. Robert D. Mariani at the Biographical Directory of Federal Judges, a public domain publication of the Federal Judicial Center. Robert David Mariani at Ballotpedia