Carbon dioxide

Carbon dioxide is a colorless gas with a density about 60% higher than that of dry air. Carbon dioxide consists of a carbon atom covalently double bonded to two oxygen atoms, it occurs in Earth's atmosphere as a trace gas. The current concentration is about 0.04% by volume, having risen from pre-industrial levels of 280 ppm. Natural sources include volcanoes, hot springs and geysers, it is freed from carbonate rocks by dissolution in water and acids; because carbon dioxide is soluble in water, it occurs in groundwater and lakes, ice caps and seawater. It is present in deposits of petroleum and natural gas. Carbon dioxide is odorless at encountered concentrations, but at high concentrations, it has a sharp and acidic odor. At such concentrations it generates the taste of soda water in the mouth; as the source of available carbon in the carbon cycle, atmospheric carbon dioxide is the primary carbon source for life on Earth and its concentration in Earth's pre-industrial atmosphere since late in the Precambrian has been regulated by photosynthetic organisms and geological phenomena.

Plants and cyanobacteria use light energy to photosynthesize carbohydrate from carbon dioxide and water, with oxygen produced as a waste product. CO2 is produced by all aerobic organisms when they metabolize carbohydrates and lipids to produce energy by respiration, it is returned to water via the gills of fish and to the air via the lungs of air-breathing land animals, including humans. Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in bread and wine making, it is produced by combustion of wood and other organic materials and fossil fuels such as coal, peat and natural gas. It is an unwanted byproduct in many large scale oxidation processes, for example, in the production of acrylic acid, it is a versatile industrial material, for example, as an inert gas in welding and fire extinguishers, as a pressurizing gas in air guns and oil recovery, as a chemical feedstock and as a supercritical fluid solvent in decaffeination of coffee and supercritical drying.

It is added to drinking water and carbonated beverages including beer and sparkling wine to add effervescence. The frozen solid form of CO2, known as dry ice is used as a refrigerant and as an abrasive in dry-ice blasting, it is a feedstock for the synthesis of chemicals. Carbon dioxide is the most significant long-lived greenhouse gas in Earth's atmosphere. Since the Industrial Revolution anthropogenic emissions – from use of fossil fuels and deforestation – have increased its concentration in the atmosphere, leading to global warming. Carbon dioxide causes ocean acidification because it dissolves in water to form carbonic acid. Carbon dioxide was the first gas to be described as a discrete substance. In about 1640, the Flemish chemist Jan Baptist van Helmont observed that when he burned charcoal in a closed vessel, the mass of the resulting ash was much less than that of the original charcoal, his interpretation was that the rest of the charcoal had been transmuted into an invisible substance he termed a "gas" or "wild spirit".

The properties of carbon dioxide were further studied in the 1750s by the Scottish physician Joseph Black. He found that limestone could be heated or treated with acids to yield a gas he called "fixed air." He observed that the fixed air supported neither flame nor animal life. Black found that when bubbled through limewater, it would precipitate calcium carbonate, he used this phenomenon to illustrate that carbon dioxide is produced by animal respiration and microbial fermentation. In 1772, English chemist Joseph Priestley published a paper entitled Impregnating Water with Fixed Air in which he described a process of dripping sulfuric acid on chalk in order to produce carbon dioxide, forcing the gas to dissolve by agitating a bowl of water in contact with the gas. Carbon dioxide was first liquefied in 1823 by Michael Faraday; the earliest description of solid carbon dioxide was given by the French inventor Adrien-Jean-Pierre Thilorier, who in 1835 opened a pressurized container of liquid carbon dioxide, only to find that the cooling produced by the rapid evaporation of the liquid yielded a "snow" of solid CO2.

The carbon dioxide molecule is centrosymmetric. The carbon–oxygen bond length is 116.3 pm, noticeably shorter than the bond length of a C–O single bond and shorter than most other C–O multiply-bonded functional groups. Since it is centrosymmetric, the molecule has no electrical dipole. Only two vibrational bands are observed in the IR spectrum – an antisymmetric stretching mode at wavenumber 2349 cm−1 and a degenerate pair of bending modes at 667 cm−1. There is a symmetric stretching mode at 1388 cm−1, only observed in the Raman spectrum. Carbon dioxide is soluble in water, in which it reversibly forms H2CO3, a weak acid since its ionization in water is incomplete. CO2 + H2O ⇌ H2CO3The hydration equilibrium constant of carbonic acid is K h = = 1.70 × 10 − 3 {\displaystyle K_==

Kevin H. Sharp

Kevin Hunter Sharp is a former United States District Judge of the United States District Court for the Middle District of Tennessee. Sharp was born on January 1963, in Memphis, Tennessee, he earned an Associate of Arts from Mesa Community College in 1988. Sharp received a Bachelor of Science, summa cum laude, from Christian Brothers College in 1990 and a Juris Doctor from Vanderbilt University School of Law in 1993. During the 111th Congress, Democrats from the Tennessee House delegation provided recommendations to the Obama White House for filling a vacancy on the United States District Court for the Middle District of Tennessee. Sharp, himself a Democrat, was included on the original list of recommendations, but the delegation recommended Nashville attorney Kathryn Barnett as its first choice. However, Sharp was the preferred choice of Republican Tennessee Senators Lamar Alexander and Bob Corker. On November 17, 2010, President Barack Obama nominated Sharp to a judgeship on the Middle District of Tennessee.

His nomination was for the seat vacated by Judge Robert L. Echols. On April 14, 2011, the Senate scheduled a vote on his nomination for May 2, 2011 and the Senate confirmed his nomination by a vote of 89 to 0, he received his commission on May 3, 2011. He had served as Chief Judge since October 1, 2014. On January 26, 2017, he sent a letter to President Trump resigning his judgeship effective April 15, 2017. Sharp's former father-in-law, Lew Conner, is a former state court judge and a prominent Republican fundraiser who has donated over forty thousand dollars to the campaigns and political action committees of Senators Lamar Alexander and Bob Corker. Kevin H. Sharp at the Biographical Directory of Federal Judges, a public domain publication of the Federal Judicial Center. Kevin Hunter Sharp at Ballotpedia

John Stowell

John F. Stowell is an American jazz guitarist, composer and lecturer. Stowell, who plays electric and acoustic guitar, was raised in Connecticut, he had private studies with John Mehegan. Several years he met bassist David Friesen in New York City. Stowell took a trip to Portland, where Friesen lives, decided to stay; the two formed a duo in 1976 that recorded and toured prolifically for seven years, with performances in the United States, Canada and Australia. The duo continues to perform thirty years after their first meeting. In 1983, Stowell and David Friesen joined flutist Paul Horn and Paul's son Robin Horn for a tour of the Soviet Union. In 1977 Stowell recorded his debut album Golden Delicious, he has been an artist-in-residence at schools in Germany, Argentina, the United States and Canada. He served as assistant director and performer at Oregon Public Broadcasting's PDX Jazz Summit in 1991, since 1995 has been a contributing columnist for a number of magazines, including Down Beat, Guitar Player, Canadian Musician and Guitar Club.

In Germany, he teaches at Jazz & Rock Schulen Freiburg with Frank Haunschild, with whom he plays regularly. He has worked with Uwe Kropinski, Dave Liebman, Hiram Mutschler, Gérard Pansanel, Gustavo Assis-Brasil, David Becker, Nicolao Valiensi. In 2005 he published Jazz Guitar Mastery. Stowell holds his guitar in a diagonal position, which facilitates playing close, piano-like voicings more comfortably. Stowell's Through the Listening Glass with David Friesen was chosen Best Jazz Albums of the Decade by the Los Angeles Examiner. Golden Delicious Through the Listening Glass with David Friesen Other Mansions with David Friesen Somewhere Picture in Black and White with Uwe Kropinski Elle Scenes The Banff Sessions Listen to This with Frank Haunschild Resonance Solitary Tales Shot Through with Beauty with Michael Zilber New York Conversations with Kendra Shank Anytime with Tomas Sauter Night Visitor with Ulf Bandgren Petit Fleur with Dave Liebman Official site John Stowell at AllMusic Portrait at Doolin Guitars Portrait at Origin Records Portland Jazz Festival 2005 at All About Jazz Excerpts from Jazz Guitar Mastery at Google Books John Stowell Interview NAMM Oral History Library