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Calcium Phosphide
Calcium phosphide (CP) is the inorganic compound with the formula Ca3P2. It is one of several phosphides of calcium, being described as the salt-like material composed of Ca2+ and P3−. Other, more exotic calcium phosphides have the formula CaP, CaP3, Ca2P2, and Ca5P8. Ca3P2 has the appearance of red-brown crystalline powder or grey lumps. Its trade name is Photophor for the incendiary use or Polytanol for the use as rodenticide. Preparation and structure It may be formed by reaction of the elements, but it is more commonly prepared by carbothermal reduction of calcium phosphate: :Ca3(PO4)2 + 8 C → Ca3P2 + 8 CO The structure of the room temperature form of Ca3P2 has not been confirmed by X-ray crystallography. A high temperature phase has been characterized by Rietveld refinement. Ca2+ centers are octahedral. Uses Metal phosphides are used as a rodenticide. A mixture of food and calcium phosphide is left where the rodents can eat it. The acid in the digestive system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphine
Phosphine (IUPAC name: phosphane) is a colorless, flammable, highly toxic compound with the chemical formula , classed as a pnictogen hydride. Pure phosphine is odorless, but technical grade samples have a highly unpleasant odor like rotting fish, due to the presence of substituted phosphine and diphosphane (). With traces of present, is spontaneously flammable in air ( pyrophoric), burning with a luminous flame. Phosphine is a highly toxic respiratory poison, and is immediately dangerous to life or health at 50 ppm. Phosphine has a trigonal pyramidal structure. Phosphines are compounds that include and the organophosphines, which are derived from by substituting one or more hydrogen atoms with organic groups. They have the general formula . Phosphanes are saturated phosphorus hydrides of the form , such as triphosphane. Phosphine, PH3, is the smallest of the phosphines and the smallest of the phosphanes. History Philippe Gengembre (1764–1838), a student of Lavois ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrotechnic Flare
A flare, also sometimes called a fusée, fusee, or bengala in some Latin-speaking countries, is a type of pyrotechnic that produces a bright light or intense heat without an explosion. Flares are used for distress signaling, illumination, or defensive countermeasures in civilian and military applications. Flares may be ground pyrotechnics, projectile pyrotechnics, or parachute-suspended to provide maximum illumination time over a large area. Projectile pyrotechnics may be dropped from aircraft, fired from rocket or artillery, or deployed by flare guns or handheld percussive tubes. History The earliest recorded use of gunpowder for signaling purposes was the 'signal bomb' used by the Chinese Song Dynasty (960–1279) as the Mongol-led Yuan Dynasty (1271–1368) besieged Yangzhou in 1276. These soft-shelled bombs, timed to explode in midair, were used to send messages to a detachment of troops far in the distance. Another mention of the signal bomb appears in a text dating f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Compounds
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 pharmaceu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphides
In chemistry, a phosphide is a compound containing the ion or its equivalent. Many different phosphides are known, with widely differing structures. Most commonly encountered on the binary phosphides, i.e. those materials consisting only of phosphorus and a less electronegative element. Numerous are polyphosphides, which are solids consisting of anionic chains or clusters of phosphorus. Phosphides are known with the majority of less electronegative elements with the exception of mercury (element), Hg, lead, Pb, antimony, Sb, bismuth, Bi, tellurium, Te, and polonium, Po.Von Schnering, H.G. and Hönle , W. (1994) "Phosphides - Solid-state Chemistry" in ''Encyclopedia of Inorganic Chemistry''. R. Bruce King (ed.). John Wiley & Sons Finally, some phosphides are molecular. Binary phosphides Binary phosphides include phosphorus and one other element. An example of a group 1 phosphide is sodium phosphide (). Other notable examples include aluminium phosphide () and calcium phosphide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus
Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Earth. It has a concentration in the Earth's crust of about one gram per kilogram (compare copper at about 0.06 grams). In minerals, phosphorus generally occurs as phosphate. Elemental phosphorus was first isolated as white phosphorus in 1669. White phosphorus emits a faint glow when exposed to oxygen – hence the name, taken from Greek mythology, meaning 'light-bearer' (Latin ), referring to the " Morning Star", the planet Venus. The term '' phosphorescence'', meaning glow after illumination, derives from this property of phosphorus, although the word has since been used for a different physical process that produces a glow. The glow of phosphorus is caused by oxidation of the white (but not red) phosphorus — a process now called chem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colin McEvedy
Colin Peter McEvedy (6 June 1930 – 1 August 2005) was a British polymath scholar, psychiatrist, historian, demographer and non-fiction author. Early life Colin Peter McEvedy was born in Salford, Lancashire on 6 June 1930. He was the third son of Peter George McEvedy, a renowned surgeon, who was born in New Zealand. Colin was educated at Harrow School, where he was a scholar, and Magdalen College, Oxford. Career McEvedy's profession was psychiatry, in which he had a distinguished career. He became perhaps better known, though, as a historian and demographer, and certainly so by the public at large. Between 1961 and 2002 he produced a number of historical atlases which, unlike most such atlases, feature fixed base-maps; in most cases, each atlas uses a single principal base-map, which is shown repeatedly, at many dates, as the atlas goes along, thus illustrating changes over the ages, from ancient down to modern, within the chosen area. The accompanying text, typically, is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greek Fire
Greek fire was an incendiary weapon used by the Eastern Roman Empire beginning . Used to set fire to enemy ships, it consisted of a combustible compound emitted by a flame-throwing weapon. Some historians believe it could be ignited on contact with water, and was probably based on naphtha and quicklime. The Byzantines typically used it in naval battles to great effect, as it could continue burning while floating on water. The technological advantage it provided was responsible for many key Byzantine military victories, most notably the salvation of Constantinople from the first and second Arab sieges, thus securing the empire's survival. The impression made by Greek fire on the western European Crusaders was such that the name was applied to any sort of incendiary weapon, including those used by Arabs, the Chinese, and the Mongols. However, these mixtures used formulas different from that of Byzantine Greek fire, which was a closely guarded state secret. Byzantines also used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Carbide
Calcium carbide, also known as calcium acetylide, is a chemical compound with the chemical formula of Ca C2. Its main use industrially is in the production of acetylene and calcium cyanamide. The pure material is colorless, while pieces of technical-grade calcium carbide are grey or brown and consist of about 80–85% of CaC2 (the rest is CaO (calcium oxide), Ca3P2 (calcium phosphide), CaS ( calcium sulfide), Ca3N2 (calcium nitride), SiC (silicon carbide), etc.). In the presence of trace moisture, technical-grade calcium carbide emits an unpleasant odor reminiscent of garlic. Applications of calcium carbide include manufacture of acetylene gas, generation of acetylene in carbide lamps, manufacture of chemicals for fertilizer, and steelmaking. Production Calcium carbide is produced industrially in an electric arc furnace from a mixture of lime and coke at approximately . This is an endothermic reaction requiring per mole and high temperatures to drive off the carbon monox ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Kingsford Smith
Sir Charles Edward Kingsford Smith (9 February 18978 November 1935), nicknamed Smithy, was an Australian aviation pioneer. He piloted the first transpacific flight and the first flight between Australia and New Zealand. Kingsford Smith was born in Brisbane. He grew up in Sydney, leaving school at the age of 16 and becoming an engineering apprentice. He joined the Australian Army in 1915 and was a motorcycle despatch rider on the Gallipoli campaign. He later transferred to the Royal Flying Corps and was awarded the Military Cross in 1917 after being shot down. After the war's end, Kingsford Smith worked as a barnstormer in England and the United States before returning to Australia in 1921. He subsequently joined West Australian Airways as one of the country's first commercial pilots. In 1928, Kingsford Smith completed the first transpacific flight, a three-leg journey from California to Brisbane via Hawaii and Fiji. He and his co-pilot Charles Ulm became celebrities, tog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torpedo
A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, such a device was called an automotive, automobile, locomotive, or fish torpedo; colloquially a ''fish''. The term ''torpedo'' originally applied to a variety of devices, most of which would today be called mines. From about 1900, ''torpedo'' has been used strictly to designate a self-propelled underwater explosive device. While the 19th-century battleship had evolved primarily with a view to engagements between armored warships with large-caliber guns, the invention and refinement of torpedoes from the 1860s onwards allowed small torpedo boats and other lighter surface vessels, submarines/ submersibles, even improvised fishing boats or frogmen, and later light aircraft, to destroy large ships without the need of large guns, though ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic Compound
In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemistry''. Inorganic compounds comprise most of the Earth's crust, although the compositions of the deep mantle remain active areas of investigation. Some simple carbon compounds are often considered inorganic. Examples include the allotropes of carbon (graphite, diamond, buckminsterfullerene, etc.), carbon monoxide, carbon dioxide, carbides, and the following salts of inorganic anions: carbonates, cyanides, cyanates, and thiocyanates. Many of these are normal parts of mostly organic systems, including organisms; describing a chemical as inorganic does not necessarily mean that it does not occur within living things. History Friedrich Wöhler's conversion of ammonium cyanate into urea in 1828 is often cited as the starting point of m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fireworks
Fireworks are a class of low explosive pyrotechnic devices used for aesthetic and entertainment purposes. They are most commonly used in fireworks displays (also called a fireworks show or pyrotechnics), combining a large number of devices in an outdoor setting. Such displays are the focal point of many cultural and religious celebrations. Fireworks take many forms to produce four primary effects: noise, light, smoke, and floating materials ( confetti most notably). They may be designed to burn with colored flames and sparks including red, orange, yellow, green, blue, purple and silver. They are generally classified by where they perform, either 'ground' or 'aerial'. Aerial fireworks may have their own propulsion ( skyrocket) or be shot into the air by a mortar (aerial shell). Most fireworks consist of a paper or pasteboard tube or casing filled with the combustible material, often pyrotechnic stars. A number of these tubes or cases may be combined so as to make whe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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