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Cornelis Adriaan Lobry Van Troostenburg De Bruyn
Cornelis Adriaan Lobry van Troostenburg de Bruyn (1 January 1857 – 23 July 1904) was a chemist from the Netherlands. Biography De Bruyn was born on in Leeuwarden, where his father, Nicholaas Lobry van Troostenburg de Bruyn, was a physician in practice. The boy was in due time sent to the high school of the town ('' Hogere Burgerschool ''), and subsequently for a year to a gymnasium. In 1875, he entered the University of Leiden, and in 1883, while acting as assistant to Professor Franchimont, he produced his dissertation and obtained his doctorate. The subject of this thesis was the interaction of the three dinitrobenzenes with potassium cyanide in alcoholic solution, an investigation to which he several times returned, and the first results of which he published in 1904. About this time De Bruyn went to Paris and worked for a few months in the laboratories of Charles-Adolphe Wurtz and of Charles Friedel, returning to Leiden in 1884, where he remained until the following year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leeuwarden
Leeuwarden (; fy, Ljouwert, longname=yes /; Town Frisian: ''Liwwadden''; Leeuwarder dialect: ''Leewarden'') is a city and municipality in Friesland, Netherlands, with a population of 123,107 (2019). It is the provincial capital and seat of the Provincial Council of Friesland. It is located about 50 km west of Groningen and 110 km north east from the Dutch capital Amsterdam (as the crow flies). The region has been continuously inhabited since the 10th century. It came to be known as Leeuwarden in the early 9th century AD and was granted city privileges in 1435. It is the main economic hub of Friesland, situated in a green and water-rich environment. Leeuwarden is a former royal residence and has a historic city centre, many historically relevant buildings, and a large shopping centre with squares and restaurants. Leeuwarden was awarded the title European Capital of Culture for 2018. The Elfstedentocht (Eleven Cities Tour), an ice skating tour passing the eleven cities of Fri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Methoxide
Sodium methoxide is the simplest sodium alkoxide. With the formula , it is a white solid, which is formed by the deprotonation of methanol. Itis a widely used reagent in industry and the laboratory. It is also a dangerously caustic base. Preparation and structure Sodium methoxide is prepared by treating methanol with sodium: : The reaction is so exothermic that ignition is possible. The resulting solution, which is colorless, is often used as a source of sodium methoxide, but the pure material can be isolated by evaporation followed by heating to remove residual methanol. As a solid, sodium methoxide is polymeric, with sheet-like arrays of centers, each bonded to four oxygen centers. The structure, and hence the basicity, of sodium methoxide in solution depends on the solvent. It is a significantly stronger base in DMSO where it is more fully ionized and free of hydrogen bonding. Applications Organic synthesis Sodium methoxide is a routinely used base in organic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1904 Deaths
Nineteen or 19 may refer to: * 19 (number), the natural number following 18 and preceding 20 * one of the years 19 BC, AD 19, 1919, 2019 Films * ''19'' (film), a 2001 Japanese film * ''Nineteen'' (film), a 1987 science fiction film Music * 19 (band), a Japanese pop music duo Albums * ''19'' (Adele album), 2008 * ''19'', a 2003 album by Alsou * ''19'', a 2006 album by Evan Yo * ''19'', a 2018 album by MHD * ''19'', one half of the double album ''63/19'' by Kool A.D. * ''Number Nineteen'', a 1971 album by American jazz pianist Mal Waldron * ''XIX'' (EP), a 2019 EP by 1the9 Songs * "19" (song), a 1985 song by British musician Paul Hardcastle. * "Nineteen", a song by Bad4Good from the 1992 album '' Refugee'' * "Nineteen", a song by Karma to Burn from the 2001 album ''Almost Heathen''. * "Nineteen" (song), a 2007 song by American singer Billy Ray Cyrus. * "Nineteen", a song by Tegan and Sara from the 2007 album '' The Con''. * "XIX" (song), a 2014 song by Slipknot. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1857 Births
Events January–March * January 1 – The biggest Estonian newspaper, ''Postimees'', is established by Johann Voldemar Jannsen. * January 7 – The partly French-owned London General Omnibus Company begins operating. * January 9 – The 7.9 Fort Tejon earthquake shakes Central and Southern California, with a maximum Mercalli intensity of IX (''Violent''). * January 24 – The University of Calcutta is established in Calcutta, as the first multidisciplinary modern university in South Asia. The University of Bombay is also established in Bombay, British India, this year. * February 3 – The National Deaf Mute College (later renamed Gallaudet University) is established in Washington, D.C., becoming the first school for the advanced education of the deaf. * February 5 – The Federal Constitution of the United Mexican States is promulgated. * March – The Austrian garrison leaves Bucharest. * March 3 ** France and the United Kingdom for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William A
William is a male given name of Germanic origin.Hanks, Hardcastle and Hodges, ''Oxford Dictionary of First Names'', Oxford University Press, 2nd edition, , p. 276. It became very popular in the English language after the Norman conquest of England in 1066,All Things William"Meaning & Origin of the Name"/ref> and remained so throughout the Middle Ages and into the modern era. It is sometimes abbreviated "Wm." Shortened familiar versions in English include Will, Wills, Willy, Willie, Bill, and Billy. A common Irish form is Liam. Scottish diminutives include Wull, Willie or Wullie (as in Oor Wullie or the play ''Douglas''). Female forms are Willa, Willemina, Wilma and Wilhelmina. Etymology William is related to the given name ''Wilhelm'' (cf. Proto-Germanic ᚹᛁᛚᛃᚨᚺᛖᛚᛗᚨᛉ, ''*Wiljahelmaz'' > German ''Wilhelm'' and Old Norse ᚢᛁᛚᛋᛅᚼᛅᛚᛘᛅᛋ, ''Vilhjálmr''). By regular sound changes, the native, inherited English form of the name shoul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkaloid
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar structure may also be termed alkaloids. In addition to carbon, hydrogen and nitrogen, alkaloids may also contain oxygen, sulfur and, more rarely, other elements such as chlorine, bromine, and phosphorus.Chemical Encyclopedia: alkaloids xumuk.ru Alkaloids are produced by a large variety of organisms including , , Medicinal plant, plants, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tautomer
Tautomers () are structural isomers (constitutional isomers) of chemical compounds that readily interconvert. The chemical reaction interconverting the two is called tautomerization. This conversion commonly results from the relocation of a hydrogen atom within the compound. The phenomenon of tautomerization is called tautomerism, also called desmotropism. Tautomerism is for example relevant to the behavior of amino acids and nucleic acids, two of the fundamental building blocks of life. Care should be taken not to confuse tautomers with depictions of "contributing structures" in chemical resonance. Tautomers are distinct chemical species that can be distinguished by their differing atomic connectivities, molecular geometries, and physicochemical and spectroscopic properties, whereas resonance forms are merely alternative Lewis structure (valence bond theory) depictions of a single chemical species, whose true structure is best described as the "average" of the idealized, hypothe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Willem Alberda Van Ekenstein
Willem Alberda van Ekenstein (March 28, 1858 – May 5, 1937) was a Dutch chemist and discovered the Lobry de Bruyn–van Ekenstein transformation together with Adriaan Lobry van Troostenburg de Bruyn. Ekenstein studied chemistry from 1876 till 1879 at the Delft University of Technology later he worked at the University of Amsterdam, University of Groningen, Dutch National Sugar Laboratory in Amsterdam Amsterdam ( , , , lit. ''The Dam on the River Amstel'') is the capital and most populous city of the Netherlands, with The Hague being the seat of government. It has a population of 907,976 within the city proper, 1,558,755 in the urban ar .... References short Biography * 1858 births 1937 deaths 20th-century Dutch chemists Academic staff of the University of Amsterdam Academic staff of the University of Groningen Scientists from Groningen (city) Delft University of Technology alumni 19th-century Dutch chemists {{Chemist-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meisenheimer Complex
A Meisenheimer complex or Jackson–Meisenheimer complex in organic chemistry is a 1:1 reaction adduct between an arene carrying electron withdrawing groups and a nucleophile. These complexes are found as reactive intermediates in nucleophilic aromatic substitution but stable and isolated Meisenheimer salts are also known. Background The early development of this type of complex takes place around the turn of the 19th century. In 1886 Janovski observed an intense violet color when he mixed ''meta''-dinitrobenzene with an alcoholic solution of alkali. In 1895 Cornelis Adriaan Lobry van Troostenburg de Bruyn investigated a red substance formed in the reaction of trinitrobenzene with potassium hydroxide in methanol. In 1900 Jackson and Gazzolo reacted trinitroanisole with sodium methoxide and proposed a quinoid structure for the reaction product. : In 1902 Jakob Meisenheimer observed that by acidifying their reaction product, the starting material was recovered. With three electron w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isomer
In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Isomers do not necessarily share similar chemical or physical properties. Two main forms of isomerism are structural or constitutional isomerism, in which ''bonds'' between the atoms differ; and stereoisomerism or spatial isomerism, in which the bonds are the same but the ''relative positions'' of the atoms differ. Isomeric relationships form a hierarchy. Two chemicals might be the same constitutional isomer, but upon deeper analysis be stereoisomers of each other. Two molecules that are the same stereoisomer as each other might be in different conformational forms or be different isotopologues. The depth of analysis depends on the field of study or the chemical and physical properties of interest. The English word "isomer" () is a back-for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vienna
en, Viennese , iso_code = AT-9 , registration_plate = W , postal_code_type = Postal code , postal_code = , timezone = CET , utc_offset = +1 , timezone_DST = CEST , utc_offset_DST = +2 , blank_name = Vehicle registration , blank_info = W , blank1_name = GDP , blank1_info = € 96.5 billion (2020) , blank2_name = GDP per capita , blank2_info = € 50,400 (2020) , blank_name_sec1 = HDI (2019) , blank_info_sec1 = 0.947 · 1st of 9 , blank3_name = Seats in the Federal Council , blank3_info = , blank_name_sec2 = GeoTLD , blank_info_sec2 = .wien , website = , footnotes = , image_blank_emblem = Wien logo.svg , blank_emblem_size = Vienna ( ; german: Wien ; ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South African Republic
The South African Republic ( nl, Zuid-Afrikaansche Republiek, abbreviated ZAR; af, Suid-Afrikaanse Republiek), also known as the Transvaal Republic, was an independent Boer Republic in Southern Africa which existed from 1852 to 1902, when it was annexed into the British Empire as a result of the Second Boer War. The ZAR was established as a result of the 1852 Sand River Convention, in which the Government of the United Kingdom, British government agreed to formally recognise independence of the Boers living north of the Vaal River. Relations between the ZAR and Britain started to deteriorate after the British Cape Colony expanded into the Southern African interior, eventually leading to the outbreak of the First Boer War between the two nations. The Boer victory confirmed the ZAR's independence; however, Anglo-ZAR tensions soon flared up again over various diplomatic issues. In 1899, war again broke out between Britain and the ZAR, which was swiftly occupied by the British mil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
