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Christian Friedrich Bucholz
Christian Friedrich Bucholz (19 September 1770 – 9 June 1818) was a German pharmaceutical chemist who is credited with the isolation of the oleoresin capsaicin in a crude form from chilli peppers using solvent extraction in 1816. Life and work Bucholz was born in Eisleben and his father worked as an apothecary. When his father died when he was still five years old, his mother married a pharmacist in Erfurt named Voigt who along with an uncle W.H.S. Bucholz trained the young boy in laboratory techniques. In 1784 he went to apprentice under the Kassel pharmacist Karl Wilhelm Fiedler and in 1794 published his first paper on the crystallization of barium acetate. In the same year he returned to Erfurt to take over his father's pharmacy. In 1805 he discovered high solubility of uranyl nitrate in organic solvents, including diethyl ether, and first studied its partitioning between water and ether depending on the concentration. This finding laid a foundation for some early methods o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oleoresin
Oleoresins are semi-solid extracts composed of resin and essential or fatty oil, obtained by evaporation of the solvents used for their production. The oleoresin of conifers is known as crude turpentine or gum turpentine, which consists of oil of turpentine and rosin. Properties In contrast to essential oils obtained by steam distillation, oleoresins abound in heavier, less volatile and lipophilic compounds, such as resins, waxes, fats and fatty oils. Gummo-oleoresins (oleo-gum resins, gum resins) occur mostly as crude balsams and contain also water-soluble gums. Processing of oleoresins is conducted on a large scale, especially in China (400,000 tons per year in the 1990s), but the technology is too labor-intensive to be viable in countries with high labor costs, such as the US. Oleoresins are prepared from spices, such as basil, capsicum (paprika), cardamom, celery seed, cinnamon bark, clove bud, fenugreek, fir balsam, ginger, jambu, labdanum, mace, marjoram, nutm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capsaicin
Capsaicin (8-methyl-''N''-vanillyl-6-nonenamide) (, rarely ) is an active component of chili peppers, which are plants belonging to the genus ''Capsicum''. It is a potent Irritation, irritant for Mammal, mammals, including humans, and produces a sensation of burning in any Tissue (biology), tissue with which it comes into contact. Capsaicin and several related amides (capsaicinoids) are produced as secondary metabolites by chili peppers, likely as deterrents against certain mammals and fungi. Pure capsaicin is a hydrophobic, colorless, highly pungent (i.e., spicy) crystalline solid. Natural function Capsaicin is present in large quantities in the Placentation#In plants, placental tissue (which holds the seeds), the internal membranes and, to a lesser extent, the other fleshy parts of the fruits of plants in the genus ''Capsicum''. The seeds themselves do not produce any capsaicin, although the highest concentration of capsaicin can be found in the white Fruit anatomy#Mesocar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid–liquid Extraction
Liquid–liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds or metal complexes, based on their relative solubility, solubilities in two different Miscibility, immiscible liquids, usually water (polar) and an organic solvent (non-polar). There is a net transfer of one or more Chemical species, species from one liquid into another liquid phase, generally from aqueous to organic. The transfer is driven by chemical potential, i.e. once the transfer is complete, the overall system of chemical components that make up the solutes and the solvents are in a more stable configuration (lower free energy). The solvent that is enriched in solute(s) is called extract. The feed solution that is depleted in solute(s) is called the raffinate. Liquid–liquid extraction is a basic technique in chemical laboratories, where it is performed using a variety of apparatus, from separatory funnels to countercurrent distribution equipment called as Mixe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eisleben
Eisleben is a town in Saxony-Anhalt, Germany. It is famous as both the hometown of the influential theologian Martin Luther and the place where he died; hence, its official name is Lutherstadt Eisleben. First mentioned in the late 10th century, Eisleben is divided into the old town of Altstadt, and new town of Neustadt. Neustadt was created for Eisleben's miners in the 14th century. As of 2020, Eisleben had a population of 22,668. It lies on the Halle–Kassel railway. History Eisleben was first mentioned in 997 as a market called Islebia, and in 1180 as a town. The counts of Mansfeld governed the area until the 18th century. During the Protestant Reformation, Count Hoyer VI of Mansfeld-Vorderort (1477–1540) remained loyal to his Catholic faith, but the family's Mittelort and Hinterort branches sided with Martin Luther. The German Peasants' War devastated the area, about a century before the Thirty Years War. Count Albert VII of Mansfeld-Hinterort (1480–1560) signed th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erfurt
Erfurt () is the capital (political), capital and largest city of the Central Germany (cultural area), Central German state of Thuringia, with a population of around 216,000. It lies in the wide valley of the Gera (river), River Gera, in the southern part of the Thuringian Basin, north of the Thuringian Forest, and in the middle of a line of the six largest Thuringian cities ('':de:Thüringer Städtekette, Thüringer Städtekette''), stretching from Eisenach in the west, via Gotha, Erfurt, Weimar and Jena, to Gera in the east. Together with Kassel and Göttingen, it is one of the cities with more than 100,000 inhabitants lying closest to the geographic centre of Germany. Erfurt is south-west of Leipzig, north-east of Frankfurt, south-west of Berlin and north of Munich. Erfurt's old town is one of the best preserved medieval city centres in Germany. The Gera (river), Gera is spanned by the Krämerbrücke, Merchants' Bridge (''Krämerbrücke''), one of the rare bridges with ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kassel
Kassel (; in Germany, spelled Cassel until 1926) is a city on the Fulda River in North Hesse, northern Hesse, in Central Germany (geography), central Germany. It is the administrative seat of the Regierungsbezirk Kassel (region), Kassel and the district Kassel (district), of the same name, and had 201,048 inhabitants in December 2020. The former capital of the States of Germany, state of Hesse-Kassel, it has many palaces and parks, including the Bergpark Wilhelmshöhe, which is a UNESCO World Heritage Site. Kassel is also known for the ''documenta'' Art exhibition, exhibitions of contemporary art. Kassel has a Public university, public University of Kassel, university with 25,000 students (2018) and a multicultural population (39% of the citizens in 2017 had a migration background). History Kassel was first mentioned in 913 AD, as the place where two deeds were signed by King Conrad of Franconia, Conrad I. The place was called ''Chasella'' or ''Chassalla'' and was a fortifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranyl Nitrate
Uranyl nitrate is a water-soluble yellow uranium salt with the formula . The hexa-, tri-, and dihydrates are known. The compound is mainly of interest because it is an intermediate in the preparation of nuclear fuels. In the nuclear industry, it is commonly referred to as yellow salt. Uranyl nitrate can be prepared by reaction of uranium salts with nitric acid. It is soluble in water, ethanol, and acetone. As determined by neutron diffraction, the uranyl center is characteristically linear with short U=O distances. In the equatorial plane of the complex are six U-O bonds to bidentate nitrate and two water ligands. At 245 pm, these U-O bonds are much longer than the U=O bonds of the uranyl center. Uses Processing of nuclear fuels Uranyl nitrate is important for nuclear reprocessing. It is the compound of uranium that results from dissolving the decladded spent nuclear fuel rods or yellowcake in nitric acid, for further separation and preparation of uranium hexafluoride for i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethyl Ether
Diethyl ether, or simply ether, is an organic compound with the chemical formula , sometimes abbreviated as . It is a colourless, highly Volatility (chemistry), volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It belongs to the ether class of organic compounds. It is a common solvent and was formerly used as a general anesthetic. Production Most diethyl ether is produced as a byproduct of the vapor-phase Hydration reaction, hydration of ethylene to make ethanol. This process uses solid-supported phosphoric acid Catalysis, catalysts and can be adjusted to make more ether if the need arises: Vapor-phase Dehydration reaction, dehydration of ethanol over some Aluminium oxide, alumina catalysts can give diethyl ether yields of up to 95%. : Diethyl ether can be prepared both in laboratories and on an industrial scale by the acid ether synthesis. Uses The dominant use of diethyl ether is as a solvent. One particular application is in the production of cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Reprocessing
Nuclear reprocessing is the chemical separation of fission products and actinides from spent nuclear fuel. Originally, reprocessing was used solely to extract plutonium for producing nuclear weapons. With commercialization of nuclear power, the reprocessed plutonium was recycled back into MOX nuclear fuel for thermal reactors. The reprocessed uranium, also known as the spent fuel material, can in principle also be re-used as fuel, but that is only economical when uranium supply is low and prices are high. Nuclear reprocessing may extend beyond fuel and include the reprocessing of other nuclear reactor material, such as Zircaloy cladding. The high radioactivity of spent nuclear material means that reprocessing must be highly controlled and carefully executed in advanced facilities by specialized personnel. Numerous processes exist, with the chemical based PUREX process dominating. Alternatives include heating to drive off volatile elements, burning via oxidation, and fluoride vola ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rudolph Brandes
Rudolph Brandes (18 October 1795 – 3 December 1842) was a German apothecary and chemist who served as the founding editor of the journal '' Archiv des Pharmazie'' from 1822. He also took an interest in meteorology and collaborated with Johann Wolfgant von Goethe and Alexander von Humboldt. Life and work Brandes was born in Salzuflen, the son of pharmacist Johann Gottlieb (1751–1816) and Friederike née Nolte. His father held license for their pharmacy in Salzuflen from 1792 and the pharmacy still exists. After studies at Osnabrück and Erfurt and he went to the University of Halle where he received a doctorate in 1817 for a dissertation titled ''Dissertatio de Strontiane mineralogico-chemica'' guided by Dr Dobereiner from Jena. His father died on October 16, 1816, and the son returned to take over his father's pharmacy. Brandes worked initially with Bucholz and after his death in 1818, he continued to work on plant compounds. He used his analytical chemistry skills to pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henri Braconnot
Henri Braconnot (; 29 May 178013 January 1855) was a French chemist and pharmacist. He was born in Commercy, his father being a counsel at the local parliament. At the death of his father, in 1787, Henri began his instruction in an elementary school in Commercy and then with private teachers. At 13, he was placed as apprentice in a pharmacy in Nancy where he learned and practiced pharmacy, chemistry, and botany. At 15, he left Nancy for a military service in a hospital in Strasbourg. In 1801-1802, he lived in Paris where he learnt in various schools, Museum, school of medicine among others, and followed the lectures of Antoine François, comte de Fourcroy, Jean-Baptiste Lamarck and Étienne Geoffroy Saint-Hilaire. He carried out some chemical investigations on the composition of a fossil horn which were published later (J Chim Phys 1806). From 1802 to his death, he lived in Nancy where he was named in 1807 as director of the botanical garden and member of the scientific acad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
