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Nuclear magnetic resonance spectroscopy

Nuclear magnetic resonance spectroscopy, most known as NMR spectroscopy or magnetic resonance spectroscopy, is a spectroscopic technique to observe local magnetic fields around atomic nuclei. The sample is placed in a magnetic field and the NMR signal is produced by excitation of the nuclei sample with radio waves into nuclear magnetic resonance, detected with sensitive radio receivers; the intramolecular magnetic field around an atom in a molecule changes the resonance frequency, thus giving access to details of the electronic structure of a molecule and its individual functional groups. As the fields are unique or characteristic to individual compounds, in modern organic chemistry practice, NMR spectroscopy is the definitive method to identify monomolecular organic compounds. Biochemists use NMR to identify proteins and other complex molecules. Besides identification, NMR spectroscopy provides detailed information about the structure, reaction state, chemical environment of molecules; the most common types of NMR are proton and carbon-13 NMR spectroscopy, but it is applicable to any kind of sample that contains nuclei possessing spin.

NMR spectra are unique, well-resolved, analytically tractable and highly predictable for small molecules. Different functional groups are distinguishable, identical functional groups with differing neighboring substituents still give distinguishable signals. NMR has replaced traditional wet chemistry tests such as color reagents or typical chromatography for identification. A disadvantage is that a large amount, 2–50 mg, of a purified substance is required, although it may be recovered through a workup. Preferably, the sample should be dissolved in a solvent, because NMR analysis of solids requires a dedicated magic angle spinning machine and may not give well-resolved spectra; the timescale of NMR is long, thus it is not suitable for observing fast phenomena, producing only an averaged spectrum. Although large amounts of impurities do show on an NMR spectrum, better methods exist for detecting impurities, as NMR is inherently not sensitive - though at higher frequencies, sensitivity is higher.

Correlation spectroscopy is a development of ordinary NMR. In two-dimensional NMR, the emission is centered around a single frequency, correlated resonances are observed; this allows identifying the neighboring substituents of the observed functional group, allowing unambiguous identification of the resonances. There are more complex 3D and 4D methods and a variety of methods designed to suppress or amplify particular types of resonances. In nuclear Overhauser effect spectroscopy, the relaxation of the resonances is observed; as NOE depends on the proximity of the nuclei, quantifying the NOE for each nucleus allows for construction of a three-dimensional model of the molecule. NMR spectrometers are expensive. Between 2000 and 2015, an NMR spectrometer cost around 500,000 - 5 million USD. Modern NMR spectrometers have a strong and expensive liquid helium-cooled superconducting magnet, because resolution directly depends on magnetic field strength. Less expensive machines using permanent magnets and lower resolution are available, which still give sufficient performance for certain applications such as reaction monitoring and quick checking of samples.

There are benchtop nuclear magnetic resonance spectrometers. NMR can be observed than a millitesla. Low-resolution NMR produces broader peaks which can overlap one another causing issues in resolving complex structures; the use of higher strength magnetic fields result in clear resolution of the peaks and is the standard in industry. Credit for the discovery of NMR goes to Isidor Isaac Rabi, who received the Nobel Prize in Physics in 1944; the Purcell group at Harvard University and the Bloch group at Stanford University independently developed NMR spectroscopy in the late 1940s and early 1950s. Edward Mills Purcell and Felix Bloch shared the 1952 Nobel Prize in Physics for their discoveries; when placed in a magnetic field, NMR active nuclei absorb electromagnetic radiation at a frequency characteristic of the isotope. The resonant frequency, energy of the radiation absorbed, the intensity of the signal are proportional to the strength of the magnetic field. For example, in a 21 Tesla magnetic field, hydrogen atoms resonate at 900 MHz.

It is common to refer to a 21 T magnet as a 900 MHz magnet since hydrogen is the most common nucleus detected, however different nuclei will resonate at different frequencies at this field strength in proportion to their nuclear magnetic moments. An NMR spectrometer consists of a spinning sample-holder inside a strong magnet, a radio-frequency emitter and a receiver with a probe that goes inside the magnet to surround the sample, optionally gradient coils for diffusion measurements, electronics to control the system. Spinning the sample is necessary to average out diffusional motion, however some experiments call for a stationary sample when solution movement is an important variable. For instance, measurements of diffusion constants are done using a stationary sample with spinning off, flow cells can be used for online analysis of process flows; the vast majority of molecules in a solution are solvent molecules, most regular solvents are hydrocarbons and so contain NMR-active protons. In order to avoid detecting only signals from solvent hydrogen atoms, deuterated solvents are used where 99+% of the protons are replaced with deuterium.

The mos

Renzo Gobbo

Renzo Gobbo is the Italian association football former manager of Sambonifacese and former player. Gobbo, a midfielder, made his playing debut with Montebelluna before to move to Como in 1980, where he made his Serie A debut. During his time at Como, Gobbo made a single appearance in the Italian U-21 team in 1981, he played for several Serie B and C teams before to retire from professional football in 1995. In 1996, he became coach of amateur team Sondrio. In 1998, he signed for Canzese, a Prima Categoria club which he led to two consecutive promotions up to Eccellenza. In 2001, he obtained the coaching license with a top grade of 110/110. After a short spell at Serie D team Usmate, which he did not manage to save from relegation, Gobbo was appointed coach of Serie C2 club Pro Vercelli in November 2002, saved the team from relegation. In April 2004 he was appointed by Carrarese, another Serie C2 team in danger of relegation, which he saved too, he coached Carrarese in 2004–2005, missing a spot in the promotion playoffs.

He was fired after the fifth matchday. In 2006, after having been considered for the Kazakhstan national football team managing position, he became assistant coach of Francesco Guidolin at Serie A club U. S. Città di Palermo. On April 23, 2007, Renzo Gobbo was appointed as caretaker alongside Rosario Pergolizzi following the dismissal of Guidolin, he however served for only three matches before being sacked himself too, being replaced by his predecessor Guidolin and moved back to his previous assistantship position alongside him. He was confirmed as assistant coach after Stefano Colantuono's signing as new head coach, being fired on late November together with Colantuono and the whole technical staff. On December 8, 2008 he was appointed as new head coach of Lega Pro Seconda Divisione club Montichiari. A relegation to Serie D under his tenure was followed by a prompt return into professionalism in 2009–10 as league champions. On July 2010 Gobbo was announced as new head coach of Lega Pro Prima Divisione club Ternana.

On 12 October 2010 he was sacked. Since 28 February to 19 March 2012 he was the coach of Sambonifacese

Linda B. Hayden

Linda Bailey Hayden is an African-American mathematician. She specializes in mathematics education and applications of mathematics in geoscience, is known for her mentorship of minorities and women in science, technology and mathematics, she is a professor and associate dean of mathematics and computer science at Elizabeth City State University. Hayden is from Portsmouth, Virginia, she grew up interested in mathematics, but because of segregation she could only read mathematics books from the Colored Community Library in Portsmouth by specially requesting them to be transferred from the town's main library. She attended the public schools in Portsmouth, including I. C. Norcom High School. Through her participation in high school mathematics competitions, she won a scholarship to Virginia State University, a black university, she graduated from Virginia State in 1970, with a bachelor's degree in mathematics and physics, earned a master's degree in mathematics education from the University of Cincinnati in 1972.

She completed a second master's degree in 1983 in computer science at Old Dominion University. After this work she returned to graduate study in mathematics education, with Mary W. Gray at American University, she completed her Ph. D. there in 1988. After earning her first master's degree in 1972, Hayden joined the mathematics department at Kentucky State University as an assistant professor, she moved to Norfolk State University in 1976, again to Elizabeth City State University in 1980. At Elizabeth City State University, she founded the Center of Excellence in Remote Sensing Education and Research, with the goal of increasing minority participation in environmental science. In 2003, Hayden won the Presidential Award for Excellence in Science and Engineering Mentoring, US Black Engineer magazine gave her their Emerald Honors for Educational Leadership. A former ice shelf in the Antarctic was named for her institution by the Advisory Committee on Antarctic Names

Ivan Garvanov

Ivan Garvanov was a Bulgarian revolutionary and leader of the revolutionary movement in Ottoman Macedonia and Southern Thrace. He was born in Stara Zagora in the Ottoman Empire, his father was a merchant, killed during the Russo-Turkish War in 1878, his uncle and grandfather had been killed by the Turks. Garvanov had been in Plovdiv at the time of the Unification of the Principality of Bulgaria and Eastern Rumelia and supported it, he learned mathematics in Sofia, Vienna, where the Austrian Academy of Sciences published a work of his. From 1894 onwards, Garvanov worked as a Bulgarian teacher in Thessaloniki. In 1897 he founded the Bulgarian Secret Revolutionary Brotherhood and entered the Internal Macedonian Adrianople Revolutionary Organization. In fact the real aim of Garvanov was to take over the IMRO, thus prevent the early outbreak of an uprising which he believed would bring disaster upon the population; however he changed his opinion and the reason was the death of his colleague Christo Ganev.

Ganev was a chemistry teacher and was killed in June 1897 in Thessaloniki by a renegade Bulgarian, who became a Serboman. Garvanov himself was wounded while trying to save his colleague, he was introduced into the organization in 1899 by Dame Gruev. In 1900 Garvanov was chosen as a leader of the Regional Committee in Salonica and in 1901 he became a member of Central Committee and a leader of the IMARO. In this way, under the leadership of Garvanov, the IMARO made a decision supporting a military revolt; as president of the Central Committee, he convened in January 1903 a congress in Thessaloniki, that resolved to launch an uprising against the Ottomans. The question regarding the timing of the uprising implicated an apparent discordance among the IMARO's leadership; this led to debates among the representatives at the Sofia IMARO's Conference in March 1903. The Centralists' majority was convinced that if the Organization would unleash an uprising, Bulgaria would declare war of the Ottomans and after the subsequent intervention of the Great Powers the Empire would collapse.

The left-wing faction warned against the risks of such unrealistic plans, opposing the uprising as inappropriate as tactics and premature by time. In April Garvanov met with Dame Gruev and Gotse Delchev and they discussed the decision of starting the uprising. Garvanov, did not participate in the Ilinden uprising, because of his arrest and exile in Rhodes after the Thessaloniki bombings of 1903. In 1904 he was settled in Sofia where he worked as a teacher; the failure of the uprising reignited the rivalries between the varying factions of the Macedonian revolutionary movement. The left-wing faction opposed Bulgarian nationalism but the Centralist's faction of the IMARO, drifted more and more towards it; the years 1905–1907 saw the slow split between the two factions. The leaders of the Centralist's were sentenced to death from the leftists. Garvanov, along with Boris Sarafov was killed by Todor Panitsa, close to the left wing leader of IMARO Yane Sandanski, in 1907. Garvanov was one of the staunchest opponents of Sandanski in the squabbles dividing the IMARO after 1903.

The assassination of Sarafov and Garvanov, turned the IMARO factions into a war of extermination that lasted for decades

John Waldegrave, 3rd Earl Waldegrave

General John Waldegrave, 3rd Earl Waldegrave was a British politician and soldier. Waldegrave was the youngest son of the 1st Earl Waldegrave, he joined the 1st Regiment of Foot in 1735, rising to the rank of captain in 1739. He became a lieutenant-colonel in the 3rd Regiment of Foot in 1743 and fought in 1745 at the Battle of Fontenoy, where he was wounded, during the War of the Austrian Succession, he became a Member of Parliament for Orford in 1747 and for Newcastle-under-Lyme in 1754. Promoted to major-general in 1757, he took part in the raid on St Malo in June 1758 and the Battle of Minden in August 1759 during the Seven Years' War, he was promoted to lieutenant-general in 1759 and became a Groom of the Bedchamber in 1760. On the death of his elder brother James Waldegrave, 2nd Earl Waldegrave without male heirs in 1763, Waldegrave inherited his titles and estates, including the family seat at Chewton Mendip, he was promoted to full general in 1772 and died in 1784. On 7 May 1751, he had married Lady Elizabeth Leveson-Gower, a younger daughter of the 1st Earl Gower and they had four children: George Waldegrave William Waldegrave Lady Elizabeth Waldegrave Lady Caroline Waldegrave Stirnet: Waldegrave1

Ed Garvey

Edward R. Garvey was an American lawyer and activist. Garvey graduated from the University of Wisconsin and spent two years in the U. S. Army. Soon after graduation, Garvey joined a Minneapolis law firm; the firm worked for the National Football League Players Association, the labor organization representing the professional American football players in the National Football League, in 1970 Garvey was assigned to counsel union president John Mackey regarding negotiations on a new four year contract with the league's owners. Garvey was offered the position of executive director in the now-certified NFLPA in 1971. Garvey served as its executive director until 1983, through two strikes and invoking antitrust legislation in his many court battles with the league. Garvey directed the NFLPA though a series of court battles that led, in 1975, to the ruling in Mackey v. NFL that antitrust laws applied to the NFL's restrictions on player movement. In 1976, armed with leverage regarding player movement from team to team and the union won major concessions from the owners.

Garvey's negotiations with the league exchanged the players' threat of pursuing a system of unfettered free agency for an improved package of player benefits. The NFLPA became recognized by the owners as a full-fledged National Labor Relations Board union, damages totaling $13.65 million were awarded to past and present players for antitrust violations against them. After leaving the NFLPA, Garvey served as deputy attorney general in Wisconsin under Bronson La Follette, serving as the number-two official in the Wisconsin Department of Justice and specializing in environmental issues. Garvey became a prominent leader with Wisconsin labor groups the Paperworkers Union in contract disputes with International Paper, he organized the Fighting Bob Fest, named for Robert M. La Follette Sr. Garvey was the editor and publisher of the political website FightingBob.com, which focused on Wisconsin and national issues from a center-left perspective. He appeared on the local NPR national public radio affiliate WHAD to provide a progressive viewpoint on a variety of topics.

In 1986, Garvey ran for the U. S. Senate from Wisconsin, losing to Republican incumbent Bob Kasten by a small margin after a bitter election. In an unsuccessful bid for Wisconsin governor in 1998 against three-term incumbent Tommy G. Thompson, Garvey sought to highlight campaign finance reform and limited contributions to his campaign to a fixed amount per donor. Thompson won by a wide margin. Garvey died in a nursing home in Wisconsin. Ed Garvey Matt Flynn Bob Kasten, 50.9% Ed Garvey, 47.4% Herb Kohl Tony Earl Ed Garvey Doug La Follette Tommy Thompson, 60% Ed Garvey, 39% "Garvey McNeil & McGillivray, S. C. Biography". Archived from the original on 2009-07-25. Retrieved 2009-08-02. FightingBob.com, Garvey's blog. FightingBobFest.org, home of an annual progressive festival conceived by Garvey. Fightin' Bob Fest