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Russell Marker
Russell Earl Marker (March 12, 1902 – March 3, 1995) was an American chemist who invented the octane rating system when he was working at the Ethyl Corporation. Later in his career, he went on to found a steroid industry in Mexico when he successfully made semisynthetic progesterone from chemical constituents found in Mexican yams in a process known as Marker degradation. This eventually led to the development at Syntex of the combined oral contraceptive pill and synthetic cortisone – and to the development of the Mexican barbasco trade. Biography He was born on March 12, 1902, in Hagerstown, Maryland. He received his B.S. in 1923 from the University of Maryland and an M.S. in physical chemistry in 1924 from the same institution. In 1926, he married Mildred Collins (1899–1985) and worked as an analytical chemist at the Naval Powder Factory in Indian Head, Maryland. He then began work at the Ethyl Corporation where he came up with the concept of the octane rating. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemist
A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms. Chemists carefully measure substance proportions, chemical reaction rates, and other chemical properties. In Commonwealth English, pharmacists are often called chemists. Chemists use their knowledge to learn the composition and properties of unfamiliar substances, as well as to reproduce and synthesize large quantities of useful naturally occurring substances and create new artificial substances and useful processes. Chemists may specialize in any number of subdisciplines of chemistry. Materials scientists and metallurgists share much of the same education and skills with chemists. The work of chemists is often related to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Chemistry
Physical chemistry is the study of macroscopic and microscopic phenomena in chemical systems in terms of the principles, practices, and concepts of physics such as motion, energy, force, time, thermodynamics, quantum chemistry, statistical mechanics, analytical dynamics and chemical equilibria. Physical chemistry, in contrast to chemical physics, is predominantly (but not always) a supra-molecular science, as the majority of the principles on which it was founded relate to the bulk rather than the molecular or atomic structure alone (for example, chemical equilibrium and colloids). Some of the relationships that physical chemistry strives to resolve include the effects of: # Intermolecular forces that act upon the physical properties of materials ( plasticity, tensile strength, surface tension in liquids). # Reaction kinetics on the rate of a reaction. # The identity of ions and the electrical conductivity of materials. # Surface science and electrochemistry of cell membrane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1902 Births
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 Slipkn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diosgenin
Diosgenin, a phytosteroid sapogenin, is the product of hydrolysis by acids, strong bases, or enzymes of saponins, extracted from the tubers of ''Dioscorea'' wild yam species, such as the Kokoro. The sugar-free (aglycone) product of such hydrolysis, diosgenin is used for the commercial synthesis of cortisone, pregnenolone, progesterone, and other steroid products. Sources It is present in detectable amounts in '' Costus speciosus'', '' Smilax menispermoidea'', ''Helicteres isora'', species of ''Paris'', ''Aletris'', ''Trigonella'', and ''Trillium'', and in extractable amounts from many species of ''Dioscorea'' – '' D. althaeoides'', '' D. colletti'', '' D. composita'', '' D. floribunda'', '' D. futschauensis'', '' D. gracillima'', '' D. hispida'', '' D. hypoglauca'', '' D. mexicana'', '' D. nipponica'', '' D. panthaica'', '' D. parviflora'', '' D. septemloba'', and '' D. zingiberensis''. Industrial uses Diosgenin is a precursor for several hormones, starting with the Marker ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dioscorea
''Dioscorea'' is a genus of over 600 species of flowering plants in the family Dioscoreaceae, native throughout the tropical and warm temperate regions of the world. The vast majority of the species are tropical, with only a few species extending into temperate climates. It was named by the monk Charles Plumier after the ancient Greek physician and botanist Dioscorides. Description Wild Yam (''Dioscorea'') is a vine that is invasive, deciduous, and herbaceous. This species is native to Asia, though, in the U.S., it is commonly found in Florida. They can grow over in length. Wild yams are an important crop, as they have been used to prevent menstrual cramps, stomach cramps, and general pain for centuries. During the 1950s scientists found that the roots of wild yams contained diosgenin which is a plant-based estrogen; diosgenin is hypothesized to aid in chemical defense against herbivores. This was used to create the first birth control pills during the 60s. In addition, some '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dioscorea Mexicana
''Dioscorea mexicana'', Mexican yam or ''cabeza de negro'' is a species of yam in the genus ''Dioscorea''. ''Dioscorea mexicana'' is a caudiciform dioscorea having either a partly to completely above-ground dome-shaped caudex with a thick, woody outer layer up to 3 feet (90 cm) in diameter and 8–10 inches (20 to 25 cm) in height. The caudex of ''D. mexicana'' is divided into regular polygonal plates that become protuberant with age, and separated by deep fissures. The vigorous annual vines which may reach 30 feet (9 m) long before dying back in winter, that grow up from the caudex, bear heart-shaped leaves. ''Dioscorea mexicana'' ranges from the state of San Luis Potosí in northeastern Mexico south to Panama. It is notable for its production of diosgenin, which is a precursor for the synthesis of hormones such as progesterone. Russell Marker developed the extraction and manufacture of hormones from ''D. mexicana'' at Syntex. Later the Mexican barbasco trade fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science History Institute
The Science History Institute is an institution that preserves and promotes understanding of the history of science. Located in Philadelphia, Pennsylvania, it includes a library, museum, archive, research center and conference center. It was founded in 1982 as a joint venture of the American Chemical Society and the University of Pennsylvania, as the Center for the History of Chemistry (CHOC). The American Institute of Chemical Engineers (AIChE) became a co-founder in 1984. It was renamed the Chemical Heritage Foundation (CHF) in 1992, and moved two years later to the institution's current location, 315 Chestnut Street in Old City, Philadelphia, Old City. On December 1, 2015, CHF merged with the Life Sciences Foundation, creating an organization that covers "the history of the life sciences and biotechnology together with the history of the chemical sciences and engineering." As of February 1, 2018, the organization was renamed the Science History Institute, to reflect its wide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liliaceae
The lily family, Liliaceae, consists of about 15 genera and 610 species of flowering plants within the order Liliales. They are monocotyledonous, perennial, herbaceous, often bulbous geophytes. Plants in this family have evolved with a fair amount of morphological diversity despite genetic similarity. Common characteristics include large flowers with parts arranged in threes: with six colored or patterned petaloid tepals (undifferentiated petals and sepals) arranged in two whorls, six stamens and a superior ovary. The leaves are linear in shape, with their veins usually arranged parallel to the edges, single and arranged alternating on the stem, or in a rosette at the base. Most species are grown from bulbs, although some have rhizomes. First described in 1789, the lily family became a paraphyletic "catch-all" (wastebasket) group of lilioid monocots that did not fit into other families and included a great number of genera now included in other families and in some cases in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarsasapogenin
Sarsasapogenin is a steroidal sapogenin, that is the aglycosidic portion of a plant saponin. It is named after sarsaparilla (''Smilax'' sp.),. a family of climbing plants found in subtropical regions. It was one of the first sapogenins to be identified, and the first spirostan steroid to be identified as such.. The identification of the spirostan structure, with its ketone spiro acetal functionality, was fundamental in the development of the Marker degradation, which allowed the industrial production of progesterone and other sex hormones from plant steroids. Sarsasapogenin is unusual in that it has a ''cis''-linkage between rings A and B of the steroid nucleus, as opposed to the more usual ''trans''-linkage found in other saturated steroids. This 5β configuration is biologically significant, as a specific enzyme – sarsasapogenin 3β-glucosyltransferase – is found in several plants for the glycosylation of sarsasapogenin. The (''S'')-configuration at C-25 is also in cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of The American Chemical Society
The ''Journal of the American Chemical Society'' is a weekly peer-reviewed scientific journal that was established in 1879 by the American Chemical Society. The journal has absorbed two other publications in its history, the ''Journal of Analytical and Applied Chemistry'' (July 1893) and the ''American Chemical Journal'' (January 1914). It covers all fields of chemistry. Since 2021, the editor-in-chief is Erick M. Carreira (ETH Zurich). In 2014, the journal moved to a hybrid open access publishing model. Abstracting and indexing The journal is abstracted and indexed in Chemical Abstracts Service, Scopus, EBSCO databases, ProQuest databases, Index Medicus/MEDLINE/PubMed, and the Science Citation Index Expanded. According to the ''Journal Citation Reports'', the journal has a 2021 impact factor of 16.383. Editors-in-chief The following people are or have been editor-in-chief: * 1879–1880 – Hermann Endemann * 1880–1881 – Gideon E. Moore * 1881–1882 – Hermann Endemann ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander H
Alexander is a male given name. The most prominent bearer of the name is Alexander the Great, the king of the Ancient Greek kingdom of Macedonia (ancient kingdom), Macedonia who created one of the largest empires in ancient history. Variants listed here are Aleksandar, Aleksander and Aleksandr. Related names and diminutives include Iskandar, Alec, Alek, Alex, Alexandre (given name), Alexandre, Aleks (given name), Aleks, Aleksa (given name), Aleksa and Sander (name), Sander; feminine forms include Alexandra, Alexandria (given name), Alexandria, and Sasha (name), Sasha. Etymology The name ''Alexander'' originates from the (; 'defending men' or 'protector of men'). It is a compound of the verb (; 'to ward off, avert, defend') and the noun (, genetive, genitive: , ; meaning 'man'). It is an example of the widespread motif of Greek names expressing "battle-prowess", in this case the ability to withstand or push back an enemy shield wall, battle line. The earliest Attested langua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
