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Augustin-Pierre Dubrunfaut
Augustin-Pierre Dubrunfaut (; 1 September 1797, Lille – 7 October 1881) was a French chemist. Mutarotation was discovered by Dubrunfaut in 1844, when he noticed that the specific rotation of aqueous sugar solution changes with time. In the same paper, he also identified that the inversion of sucrose in the presence of brewer's yeast (''Saccharomyces cerevisiae'') was not a consequence of fermentation. The organic fructose molecule was subsequently discovered by Dubrunfaut in 1847. He also discovered maltose, although this discovery was not widely accepted until it was confirmed in 1872 by Cornelius O'Sullivan Cornelius O'Sullivan, FRS (20 December 1841 – 8 January 1907) was an Irish brewer's chemist. He was born the son of merchant James O'Sullivan of Bandon, County Cork and was educated locally, before winning a scholarship to study chemistry at th .... Works * ''Art de fabriquer le sucre de betteraves, contenant 1. la description des meilleures méthodes usitées pour la c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lille
Lille ( , ; nl, Rijsel ; pcd, Lile; vls, Rysel) is a city in the northern part of France, in French Flanders. On the river Deûle, near France's border with Belgium, it is the capital of the Hauts-de-France region, the prefecture of the Nord department, and the main city of the European Metropolis of Lille. The city of Lille proper had a population of 234,475 in 2019 within its small municipal territory of , but together with its French suburbs and exurbs the Lille metropolitan area (French part only), which extends over , had a population of 1,510,079 that same year (Jan. 2019 census), the fourth most populated in France after Paris, Lyon, and Marseille. The city of Lille and 94 suburban French municipalities have formed since 2015 the European Metropolis of Lille, an indirectly elected metropolitan authority now in charge of wider metropolitan issues, with a population of 1,179,050 at the Jan. 2019 census. More broadly, Lille belongs to a vast conurbation formed w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutarotation
Mutarotation is the change in the '' optical rotation'' because of the change in the equilibrium between two anomers, when the corresponding stereocenters interconvert. Cyclic sugars show mutarotation as α and β anomeric forms interconvert. The optical rotation of the solution depends on the optical rotation of each anomer and their ratio in the solution. Mutarotation was discovered by French chemist Augustin-Pierre Dubrunfaut in 1844, when he noticed that the specific rotation of aqueous sugar solution changes with time. Measurement The α and β anomers are diastereomers of each other and usually have different specific rotations. A solution or liquid sample of a pure α anomer will rotate plane polarised light by a different amount and/or in the opposite direction than the pure β anomer of that compound. The optical rotation of the solution depends on the optical rotation of each anomer and their ratio in the solution. For example, if a solution of β-D-glucopyranose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fructose
Fructose, or fruit sugar, is a ketonic simple sugar found in many plants, where it is often bonded to glucose to form the disaccharide sucrose. It is one of the three dietary monosaccharides, along with glucose and galactose, that are absorbed by the gut directly into the blood of the portal vein during digestion. The liver then converts both fructose and galactose into glucose, so that dissolved glucose, known as blood sugar, is the only monosaccharide present in circulating blood. Fructose was discovered by French chemist Augustin-Pierre Dubrunfaut in 1847. The name "fructose" was coined in 1857 by the English chemist William Allen Miller. Pure, dry fructose is a sweet, white, odorless, crystalline solid, and is the most water-soluble of all the sugars. Fructose is found in honey, tree and vine fruits, flowers, berries, and most root vegetables. Commercially, fructose is derived from sugar cane, sugar beets, and maize. High-fructose corn syrup is a mixture of glucose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maltose
} Maltose ( or ), also known as maltobiose or malt sugar, is a disaccharide formed from two units of glucose joined with an α(1→4) bond. In the isomer isomaltose, the two glucose molecules are joined with an α(1→6) bond. Maltose is the two-unit member of the amylose homologous series, the key structural motif of starch. When beta-amylase breaks down starch, it removes two glucose units at a time, producing maltose. An example of this reaction is found in germinating seeds, which is why it was named after malt. Unlike sucrose, it is a reducing sugar. History Maltose was discovered by Augustin-Pierre Dubrunfaut, although this discovery was not widely accepted until it was confirmed in 1872 by Irish chemist and brewer Cornelius O'Sullivan. Its name comes from malt, combined with the suffix '-ose' which is used in names of sugars. Structure and nomenclature Carbohydrates are generally divided into monosaccharides, oligosaccharides, and polysaccharides depending on the n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cornelius O'Sullivan
Cornelius O'Sullivan, FRS (20 December 1841 – 8 January 1907) was an Irish brewer's chemist. He was born the son of merchant James O'Sullivan of Bandon, County Cork and was educated locally, before winning a scholarship to study chemistry at the Royal School of Mines, London. After completing the three-year course he joined the Royal College of Chemistry as a student assistant to Professor August Wilhelm von Hofmann. When Hofman returned to Germany in 1865 to become Professor of Chemistry in Berlin he took O'Sullivan with him as his assistant. The following year Hofman's influence had secured O'Sullivan the post of assistant brewer and chemist to Messrs. Bass & Co. at Burton-on-Trent, Staffordshire, a major centre for English brewing. At Bass he applied his chemical knowledge and aptitude for original research to the scientific and practical issues of brewing and ultimately became head of the scientific and analytical staff of the company, a post he held for the rest of his ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
19th-century French Chemists
The 19th (nineteenth) century began on 1 January 1801 ( MDCCCI), and ended on 31 December 1900 ( MCM). The 19th century was the ninth century of the 2nd millennium. The 19th century was characterized by vast social upheaval. Slavery was abolished in much of Europe and the Americas. The First Industrial Revolution, though it began in the late 18th century, expanding beyond its British homeland for the first time during this century, particularly remaking the economies and societies of the Low Countries, the Rhineland, Northern Italy, and the Northeastern United States. A few decades later, the Second Industrial Revolution led to ever more massive urbanization and much higher levels of productivity, profit, and prosperity, a pattern that continued into the 20th century. The Islamic gunpowder empires fell into decline and European imperialism brought much of South Asia, Southeast Asia, and almost all of Africa under colonial rule. It was also marked by the collapse of the large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1797 Births
Events January–March * January 3 – The Treaty of Tripoli, a peace treaty between the United States and Ottoman Tripolitania, is signed at Algiers (''see also'' 1796). * January 7 – The parliament of the Cisalpine Republic adopts the Italian green-white-red tricolour as the official flag (this is considered the birth of the flag of Italy). * January 13 – Action of 13 January 1797, part of the War of the First Coalition: Two British Royal Navy frigates, HMS ''Indefatigable'' and HMS ''Amazon'', drive the French 74-gun ship of the line '' Droits de l'Homme'' aground on the coast of Brittany, with over 900 deaths. * January 14 – War of the First Coalition – Battle of Rivoli: French forces under General Napoleon Bonaparte defeat an Austrian army of 28,000 men, under ''Feldzeugmeister'' József Alvinczi, near Rivoli (modern-day Italy), ending Austria's fourth and final attempt to relieve the fortress city of Mantua. * January 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1881 Deaths
Events January–March * January 1– 24 – Siege of Geok Tepe: Russian troops under General Mikhail Skobelev defeat the Turkomans. * January 13 – War of the Pacific – Battle of San Juan and Chorrillos: The Chilean army defeats Peruvian forces. * January 15 – War of the Pacific – Battle of Miraflores: The Chileans take Lima, capital of Peru, after defeating its second line of defense in Miraflores. * January 24 – William Edward Forster, chief secretary for Ireland, introduces his Coercion Bill, which temporarily suspends habeas corpus so that those people suspected of committing an offence can be detained without trial; it goes through a long debate before it is accepted February 2. * January 25 – Thomas Edison and Alexander Graham Bell form the Oriental Telephone Company. * February 13 – The first issue of the feminist newspaper ''La Citoyenne'' is published by Hubertine Auclert. * February 16 &ndas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
