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Auguste Verneuil
Auguste Victor Louis Verneuil (; 3 November 1856 – 27 April 1913) was a French chemist who invented the first commercially viable process for the manufacture of synthetic gemstones. In 1902 he discovered the "flame fusion" process, called the Verneuil process, which is an inexpensive method of making artificial corundum, or rubies and sapphires. Biography Verneuil was born in Dunkirk, France, in 1856. He was the son of a watchmaker-mechanic. When he was 17, chemist Edmond Frémy accepted him as a laboratory assistant. He received his bachelor's degree in 1875, his master's in 1880 and his PhD in 1886. In 1892 he became a professor of applied chemistry in the organic chemistry section of the Museum of Natural History in Paris, where he worked for 13 years. His first publication was with L. Bourgeois in 1880 on the preparation of crystalline hydrous iron arsenate. He studied methods to synthesize ruby, the chemistry of selenium, the phosphorescence of zincblende, the chemis ...
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Phosphorescence
Phosphorescence is a type of photoluminescence related to fluorescence. When exposed to light (radiation) of a shorter wavelength, a phosphorescent substance will glow, absorbing the light and reemitting it at a longer wavelength. Unlike fluorescence, a phosphorescent material does not immediately reemit the radiation it absorbs. Instead, a phosphorescent material absorbs some of the radiation energy and reemits it for a much longer time after the radiation source is removed. In a general sense, there is no distinct boundary between the emission times of fluorescence and phosphorescence (i.e.: if a substance glows under a black light it is generally considered fluorescent, and if it glows in the dark it is often simply called phosphorescent). In a modern, scientific sense, the phenomena can usually be classified by the three different mechanisms that produce the light, and the typical timescales during which those mechanisms emit light. Whereas fluorescent materials stop emitti ...
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19th-century French Chemists
The 19th century began on 1 January 1801 (represented by the Roman numerals MDCCCI), and ended on 31 December 1900 (MCM). It was the 9th century of the 2nd millennium. It was characterized by vast social upheaval. Slavery was Abolitionism, abolished in much of Europe and the Americas. The First Industrial Revolution, though it began in the late 18th century, expanded beyond its British homeland for the first time during the 19th century, particularly remaking the economies and societies of the Low Countries, France, 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 Catholic Church, in response to the growing influence and power of modernism, secularism and materialism, formed the First Vatican Council in the late 19th century to deal with such problems an ...
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1913 Deaths
Events January * January – Joseph Stalin travels to Vienna to research his ''Marxism and the National Question''. This means that, during this month, Stalin, Hitler, Trotsky and Tito are all living in the city. * January 3 – First Balkan War: Greece completes its Battle of Chios (1912), capture of the eastern Aegean island of Chios, as the last Ottoman forces on the island surrender. * January 13 – Edward Carson founds the (first) Ulster Volunteers, Ulster Volunteer Force, by unifying several existing Ulster loyalism, loyalist militias to resist home rule for Ireland. * January 18 – First Balkan War: Battle of Lemnos (1913), Battle of Lemnos – Greek admiral Pavlos Kountouriotis forces the Turkish fleet to retreat to its base within the Dardanelles, from which it will not venture for the rest of the war. * January 23 – 1913 Ottoman coup d'état: Enver Pasha comes to power. February * February 1 – New York City's Grand Central Te ...
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1856 Births
Events January–March * January 8 – Borax deposits are discovered in large quantities by John Veatch in California. * January 23 – The American sidewheel steamer SS ''Pacific'' leaves Liverpool (England) for a transatlantic voyage on which she will be lost with all 186 on board. * January 24 – U.S. President Franklin Pierce declares the new Free-State Topeka government in " Bleeding Kansas" to be in rebellion. * January 26 – First Battle of Seattle: Marines from the suppress an indigenous uprising, in response to Governor Stevens' declaration of a "war of extermination" on Native communities. * January 29 ** The 223-mile North Carolina Railroad is completed from Goldsboro through Raleigh and Salisbury to Charlotte. ** Queen Victoria institutes the Victoria Cross as a British military decoration. * February ** The Tintic War breaks out in Utah. ** The National Dress Reform Association is founded in the United States to promote "r ...
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People From Dunkirk
The term "the people" refers to the public or common mass of people of a polity. As such it is a concept of human rights law, international law as well as constitutional law, particularly used for claims of popular sovereignty. In contrast, a people is any plurality of persons considered as a whole. Used in politics and law, the term "a people" refers to the collective or community of an ethnic group or nation. Concepts Legal Chapter One, Article One of the Charter of the United Nations states that "peoples" have the right to self-determination. Though the mere status as peoples and the right to self-determination, as for example in the case of Indigenous peoples (''peoples'', as in all groups of indigenous people, not merely all indigenous persons as in ''indigenous people''), does not automatically provide for independent sovereignty and therefore secession. Indeed, judge Ivor Jennings identified the inherent problems in the right of "peoples" to self-determination, as i ...
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Glass
Glass is an amorphous (non-crystalline solid, non-crystalline) solid. Because it is often transparency and translucency, transparent and chemically inert, glass has found widespread practical, technological, and decorative use in window panes, tableware, and optics. Some common objects made of glass are named after the material, e.g., a Tumbler (glass), "glass" for drinking, "glasses" for vision correction, and a "magnifying glass". Glass is most often formed by rapid cooling (quenching) of the Melting, molten form. Some glasses such as volcanic glass are naturally occurring, and obsidian has been used to make arrowheads and knives since the Stone Age. Archaeological evidence suggests glassmaking dates back to at least 3600 BC in Mesopotamia, Ancient Egypt, Egypt, or Syria. The earliest known glass objects were beads, perhaps created accidentally during metalworking or the production of faience, which is a form of pottery using lead glazes. Due to its ease of formability int ...
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Glycerine
Glycerol () is a simple triol compound. It is a colorless, odorless, sweet-tasting, viscous liquid. The glycerol backbone is found in lipids known as glycerides. It is also widely used as a sweetener in the food industry and as a humectant in pharmaceutical formulations. Because of its three hydroxyl groups, glycerol is miscible with water and is hygroscopic in nature. Modern use of the word glycerine (alternatively spelled glycerin) refers to commercial preparations of less than 100% purity, typically 95% glycerol. Structure Although achiral, glycerol is prochiral with respect to reactions of one of the two primary alcohols. Thus, in substituted derivatives, the stereospecific numbering labels the molecule with a ''sn''- prefix before the stem name of the molecule. Production Natural sources Glycerol is generally obtained from plant and animal sources where it occurs in triglycerides, esters of glycerol with long-chain carboxylic acids. The hydrolysis, saponificatio ...
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Rare Earth Element
The rare-earth elements (REE), also called the rare-earth metals or rare earths, and sometimes the lanthanides or lanthanoids (although scandium and yttrium, which do not belong to this series, are usually included as rare earths), are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals. Compounds containing rare earths have diverse applications in electrical and electronic components, lasers, glass, magnetic materials, and industrial processes. The term "rare-earth" is a misnomer because they are not actually scarce, but historically it took a long time to isolate these elements. They are relatively plentiful in the entire Earth's crust ( cerium being the 25th-most-abundant element at 68 parts per million, more abundant than copper), but in practice they are spread thinly as trace impurities, so to obtain rare earths at usable purity requires processing enormous amounts of raw ore at great expense; thus the name "rare" earths. Scandium and yttrium a ...
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Zincblende
Sphalerite is a sulfide mineral with the chemical formula . It is the most important ore of zinc. Sphalerite is found in a variety of deposit types, but it is primarily in sedimentary exhalative, Mississippi-Valley type, and volcanogenic massive sulfide deposits. It is found in association with galena, chalcopyrite, pyrite (and other sulfides), calcite, dolomite, quartz, rhodochrosite, and fluorite. German geologist Ernst Friedrich Glocker discovered sphalerite in 1847, naming it based on the Greek word ''sphaleros'', meaning "deceiving", due to the difficulty of identifying the mineral. In addition to zinc, sphalerite is an ore of cadmium, gallium, germanium, and indium. Miners have been known to refer to sphalerite as ''zinc blende'', ''black-jack'', and ''ruby blende''. Marmatite is an opaque black variety with a high iron content. Crystal habit and structure Sphalerite crystallizes in the face-centered cubic zincblende crystal structure, which was named after the m ...
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Selenium
Selenium is a chemical element; it has symbol (chemistry), symbol Se and atomic number 34. It has various physical appearances, including a brick-red powder, a vitreous black solid, and a grey metallic-looking form. It seldom occurs in this elemental state or as pure ore compounds in Earth's crust. Selenium ( ) was discovered in 1817 by , who noted the similarity of the new element to the previously discovered tellurium (named for the Earth). Selenium is found in :Sulfide minerals, metal sulfide ores, where it substitutes for sulfur. Commercially, selenium is produced as a byproduct in the refining of these ores. Minerals that are pure selenide or selenate compounds are rare. The chief commercial uses for selenium today are glassmaking and pigments. Selenium is a semiconductor and is used in photocells. Applications in electronics, once important, have been mostly replaced with silicon semiconductor devices. Selenium is still used in a few types of Direct current, DC power surge ...
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Verneuil Torch Sketch
Verneuil may refer to: Places in France *Verneuil, former municipality, now merged with Moussy-Verneuil, Aisne department * Verneuil, Charente, in the Charente department * Verneuil, Cher, in the Cher department *Verneuil, Marne, in the Marne department * Verneuil, Nièvre, in the Nièvre department * Verneuil-en-Bourbonnais, in the Allier department *Verneuil-en-Halatte, in the Oise department * Verneuil-Grand, in the Meuse department * Verneuil-le-Château, in the Indre-et-Loire department * Verneuil-l'Étang, in the Seine-et-Marne department * Verneuil-Moustiers, in the Haute-Vienne department * Verneuil-Petit, in the Meuse department * Verneuil-sous-Coucy, in the Aisne department *Verneuil-sur-Avre, in the Eure department * Verneuil-sur-Igneraie, in the Indre department * Verneuil-sur-Indre, in the Indre-et-Loire department * Verneuil-sur-Seine, in the Yvelines department * Verneuil-sur-Serre, in the Aisne department * Verneuil-sur-Vienne, in the Haute-Vienne department People ...
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