|
Georges Friedel
Georges Friedel (19 July 1865 – 11 December 1933) was a French Mineralogy, mineralogist and Crystallography, crystallographer. Life Georges was the son of the chemist Charles Friedel. Georges' grandfather was Georges Louis Duvernoy, Louis Georges Duvernoy who held the chair in comparative anatomy from 1850 to 1855 at the Muséum national d'histoire naturelle. Georges studied at the École Polytechnique in Paris and the École des mines de Saint-Étienne, École Nationale des Mines in St. Etienne, and was a student of François Ernest Mallard. In 1893 he obtained a professorship at the École Nationale des Mines, the director of which he would later become. After the World War I, First World War, he returned as a professor at the University of Strasbourg in Alsace. Due to ill health, he took early retirement in 1930, and died in 1933. He was married with five children. Scientific works Like his teacher Mallard, Friedel concerned himself with the theories of Auguste Bravais, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mulhouse
Mulhouse (; Alsatian language, Alsatian: or , ; ; meaning ''Mill (grinding), mill house'') is a city of the Haut-Rhin Departments of France, department, in the Grand Est Regions of France, region, eastern France, close to the France–Switzerland border, Swiss and France–Germany border, German borders. It is the largest city in Haut-Rhin and second largest in Alsace after Strasbourg. Mulhouse is famous for its museums, especially the (also known as the , 'National Museum of the Automobile') and the (also known as , 'French Museum of the Railway'), respectively the largest automobile and railway museums in the world. An industrial town nicknamed "the French Manchester", Mulhouse is also the main seat of the Upper Alsace University, where the secretariat of the European Physical Society is found. Administration Mulhouse is a Communes of France, commune with a population of 108,312 in 2019. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auguste Bravais
Auguste Bravais (; 23 August 1811, Annonay, Ardèche – 30 March 1863, Le Chesnay, France) was a French physicist known for his work in crystallography, the conception of Bravais lattices, and the formulation of Bravais law. Bravais also studied magnetism, the northern lights, meteorology, geobotany, phyllotaxis, astronomy, statistics and hydrography. He studied at the Collège Stanislas in Paris before joining the École Polytechnique in 1829, where he was a classmate of groundbreaking mathematician Évariste Galois, whom Bravais actually beat in a scholastic mathematics competition. Towards the end of his studies he became a naval officer, and sailed on the ''Finistere'' in 1832 as well as the ''Loiret'' afterwards. He took part in hydrographic work along the Algerian Coast. He participated in the ''Recherche'' expedition and helped the ''Lilloise'' in Spitzbergen and Lapland. Bravais taught a course in applied mathematics for astronomy in the Faculty of Sciences in Lyon, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smectic
Liquid crystal (LC) is a state of matter whose properties are between those of conventional liquids and those of solid crystals. For example, a liquid crystal may flow like a liquid, but its molecules may be oriented in a crystal-like way. There are many types of LC phases, which can be distinguished by their optical properties (such as textures). The contrasting textures arise due to molecules within one area of material ("domain") being oriented in the same direction but different areas having different orientations. LC materials may not always be in a LC state of matter (just as water may be ice or water vapor). Liquid crystals can be divided into 3 main types: *thermotropic, * lyotropic, and * metallotropic. Thermotropic and lyotropic liquid crystals consist mostly of organic molecules, although a few minerals are also known. Thermotropic LCs exhibit a phase transition into the LC phase as temperature changes. Lyotropic LCs exhibit phase transitions as a function of both ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disclination
In crystallography, a disclination is a line defect in which rotational symmetry is violated. In analogy with dislocations in crystals, the term, ''disinclination'', for liquid crystals first used by Frederick Charles Frank and since then has been modified to its current usage, ''disclination''. It is a defect in the orientation of director whereas a dislocation is a defect in positional order. Example in two dimensions In 2D, disclinations and dislocations are point defects instead of line defects as in 3D. They are topological defects and play a central role in melting of 2D crystals within the KTHNY theory, based on two Kosterlitz–Thouless transitions. Equally sized discs (spheres, particles, atoms) form a hexagonal crystal as dense packing in two dimensions. In such a crystal, each particle has six nearest neighbors. Local strain and twist (for example induced by thermal motion) can cause configurations where discs (or particles) have a coordination number different of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nematic
Liquid crystal (LC) is a state of matter whose properties are between those of conventional liquids and those of solid crystals. For example, a liquid crystal may flow like a liquid, but its molecules may be oriented in a crystal-like way. There are many types of LC Phase (matter), phases, which can be distinguished by their Optics, optical properties (such as Texture (crystalline), textures). The contrasting textures arise due to molecules within one area of material ("domain") being oriented in the same direction but different areas having different orientations. LC materials may not always be in a LC state of matter (just as water may be ice or water vapor). Liquid crystals can be divided into 3 main types: *thermotropic, *lyotropic, and *#Metallotropic liquid crystals, metallotropic. Thermotropic and lyotropic liquid crystals consist mostly of organic molecules, although a few minerals are also known. Thermotropic LCs exhibit a phase transition into the LC phase as tempera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annales De Chimie Et De Physique
__NOTOC__ ''Annales de chimie et de physique'' ( French for ''Annals of Chemistry and Physics'') is a scientific journal founded in Paris, France, in 1789 under the title ''Annales de chimie''. One of the early editors was the French chemist Antoine Lavoisier. Lavoisier, an aristocrat, was guillotined in May 1794, ostensibly for tax fraud: and the journal was not published from 1794 to 1796 while the Reign of Terror was at its height under the French Directory. In 1815, it became the ''Annales de chimie et de physique'', and was published under that name for the next 100 years. In 1914, it split into two successor journals. The first one, '' Annales de physique'', was latterly published by EDP Sciences under the same name up to 2009, when it became integrated in the ''European Physical Journal'' series as the '' European Physical Journal H – Historical Perspectives on Contemporary Physics''. The second successor, ''Annales de chimie'', later became '' Annales de chimie: Scien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
François Grandjean
François () is a French masculine given name and surname, equivalent to the English name Francis. People with the given name * Francis I of France, King of France (), known as "the Father and Restorer of Letters" * Francis II of France, King of France and King consort of Scots (), known as the husband of Mary Stuart, Queen of Scots * François Amoudruz (1926–2020), French resistance fighter * François-Marie Arouet (better known as Voltaire; 1694–1778), French Enlightenment writer, historian, and philosopher *François Aubry (other), several people *François Baby (other), several people * François Beauchemin (born 1980), Canadian ice hockey player for the Anaheim Duck *François Blanc (1806–1877), French entrepreneur and operator of casinos *François Boucher (other), several people *François Caron (other), several people * François Cevert (1944–1973), French racing driver * François Chau (born 1959), Cambodian American actor * F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholesteryl Benzoate
Cholesteryl benzoate, also called 5-cholesten-3-yl benzoate, is an organic chemical, an ester of cholesterol and benzoic acid. It is a liquid crystal material forming cholesteric liquid crystals with helical structure. It can be used with cholesteryl nonanoate and cholesteryl oleyl carbonate in some thermochromic liquid crystals. It is used in some hair colors, make-ups, and some other cosmetic preparations. It can be also used as a component of the liquid crystals used for liquid crystal displays. Cholesteryl benzoate was the first material in which liquid crystal properties were discovered. In the late 1880s Friedrich Reinitzer, an Austrian botanist Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek wo ..., while studying the chemicals in plants, heated cholesteryl benzoate. At 145&nb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Friedrich Reinitzer
Friedrich Richard Reinitzer (25 February 1857 in Prague – 16 February 1927 in Graz) was an Austrian botanist and chemist. In late 1880s, experimenting with cholesteryl benzoate, he discovered properties of liquid crystals (named later by Otto Lehmann). Reinitzer was born into a German Bohemian family in Prague. He studied chemistry at the German technical university in Prague; in 1883 he was habilitated there as a private docent. From 1888-1901 he was a professor at Karl-Ferdinands-Universität, then professor at technical university in Graz. During 1909 - 1910 he served as the rector of the university. While at Karl-Ferdinands-Universität in 1888 he discovered a strange behaviour of what would later be called liquid crystals. For the explanation of their behaviour he collaborated with the physicist Otto Lehmann from Aachen. The discovery received plenty of attention at the time but no practical uses were apparent and the interest dropped soon. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macle
{{no footnotes, date=April 2009 Macle is a term used in crystallography. It is a crystalline form, twin-crystal or double crystal (such as chiastolite). It is crystallographic twin according to the spinel twin law and is seen in octahedral crystals or minerals such as diamond and spinel. The twin law name comes from the fact that is commonly observed in the mineral spinel. ''Macle'' is an old French word, a heraldic term for a voided lozenge (one diamond shape within another). Etymologically the word is derived from the Latin ''macula'' meaning spot, mesh A mesh is a barrier made of connected strands of metal, fiber, or other flexible or ductile materials. A mesh is similar to a web or a net in that it has many attached or woven strands. Types * A plastic mesh may be extruded, oriented, ex ..., or hole. Bibliography * Georges Friedel (1904) "Étude sur les groupements cristallins", ''Extrait du Bulletin de la Société de l'Industrie minérale'', Quatrième série, T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Aluminate
Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to its heavier homologues strontium and barium. It is the fifth most abundant element in Earth's crust, and the third most abundant metal, after iron and aluminium. The most common calcium compound on Earth is calcium carbonate, found in limestone and the fossilised remnants of early sea life; gypsum, anhydrite, fluorite, and apatite are also sources of calcium. The name derives from Latin ''calx'' "lime", which was obtained from heating limestone. Some calcium compounds were known to the ancients, though their chemistry was unknown until the seventeenth century. Pure calcium was isolated in 1808 via electrolysis of its oxide by Humphry Davy, who named the element. Calcium compounds are widely used in many industries: in foods and pharmaceut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal
A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macroscopic single crystals are usually identifiable by their geometrical shape, consisting of flat faces with specific, characteristic orientations. The scientific study of crystals and crystal formation is known as crystallography. The process of crystal formation via mechanisms of crystal growth is called crystallization or solidification. The word ''crystal'' derives from the Ancient Greek word (), meaning both "ice" and "rock crystal", from (), "icy cold, frost". Examples of large crystals include snowflakes, diamonds, and table salt. Most inorganic solids are not crystals but polycrystals, i.e. many microscopic crystals fused together into a single solid. Polycrystals include most metals, rocks, ceramics, and ice. A third category of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Annales De Chimie Et De Physique")
