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Roman Candle (firework)
A Roman candle is a traditional type of firework that ejects one or more stars or exploding shells. Roman candles come in a variety of sizes, from diameter for consumers, up to diameter in professional fireworks displays. Roman candles are banned in some countries as they have a tendency to malfunction. They are banned in Finland and the Netherlands, and illegal to possess or set off in the U.S. states of California, Delaware, Florida, Maryland, Massachusetts, Minnesota, New Jersey, New York, North Carolina, Oregon, and Rhode Island. Construction and ignition Roman candles are fireworks constructed with bentonite, lifting charge, pyrotechnic star, black powder, and delay charge. The device is ignited from the top, which should be pointed into the sky, away from people. The delay powder is packed tightly in the tube, so that the flame cannot reach around the sides of the plug of delay composition. It therefore burns slowly; as it is consumed, the flame moves down through th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WFMY
WFMY-TV (channel 2) is a television station licensed to Greensboro, North Carolina, United States, serving as the CBS affiliate for the Piedmont Triad region. Owned by Tegna Inc., the station maintains studios on Phillips Avenue in Greensboro and a transmitter in Randleman, North Carolina. WFMY began broadcasting in 1949; it was the second television station in North Carolina after WBTV in Charlotte and the first to originate a live broadcast. It was owned by the Greensboro News Company, publishers of the ''Greensboro Daily News'' and ''Daily Record''. It aired programming from all major networks in its early years, when it was the only station in the Triad, though it was always primarily a CBS affiliate. WFMY became the highest-rated station in the market and the traditional ratings leader, with such regionally popular local shows as ''The Old Rebel Show'' and ''The Good Morning Show''. Beginning in the late 1990s, sharper competition from the other major stations in the mar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comet (pyrotechnics)
A comet is a type of firework star fired into the sky from the ground which leaves a long trail of sparks in its wake as it flies through the air. A low noise effect that is popular in pyro-musicals because comets can be easily synchronized to music given their instantaneous impact. A comet may also be a small block attached to the outside of a shell which burns and emits sparks as the shell is rising, leaving a trail in the sky. Some comets use a matrix composition with small stars A star is a luminous spheroid of plasma held together by self-gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night; their immense distances from Earth make them appear as fixed points of ... embedded in it. The matrix composition burns with little light but ignites the stars, producing the effect. Some freely-launched comets contain crossette breaks, which explode and break the comet into several pieces to produce a branching effect. Co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Ballistics
Internal ballistics (also interior ballistics), a subfield of ballistics, is the study of the propulsion of a projectile. In guns, internal ballistics covers the time from the propellant's ignition until the projectile exits the gun barrel. The study of internal ballistics is important to designers and users of firearms of all types, from small-bore rifles and pistols, to artillery. For rocket-propelled projectiles, internal ballistics covers the period during which a rocket motor is providing thrust. General concepts Interior ballistics can be considered in three time periods: *Lock time - the time from sear release until the primer is struck *Ignition time - the time from when the primer is struck until the projectile starts to move *Barrel time - the time from when the projectile starts to move until it exits the barrel. The burning firearm propellant produces energy in the form of hot gases that raise the chamber pressure which applies a force on the base of the projectile, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuse (explosives)
In an explosive, pyrotechnics, pyrotechnic device, or military munition, a fuse (or fuze) is the part of the device that initiates function. In common usage, the word fuse is used indiscriminately. However, when being specific (and in particular in a military context), the term ''fuse'' describes a simple pyrotechnic initiating device, like the cord on a firecracker whereas the term ''fuze'' is used when referring to a more sophisticated ignition device incorporating mechanical and/or electronics, electronic components, such as a proximity fuze for an M107 projectile, M107 artillery shell, magnetometer, magnetic or acoustic signature, acoustic fuze on a sea mine, spring-loaded grenade fuze, pencil detonator, or anti-handling device. History Documented evidence suggests that the earliest fuses were first used by the Song dynasty, Song Chinese between the 10th and 12th centuries. After the Chinese invented gunpowder, they began adapting its explosive properties for use in milit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clay
Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolinite, ). Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impurities, such as a reddish or brownish colour from small amounts of iron oxide. Clays develop plasticity (physics), plasticity when wet but can be hardened through Pottery#Firing, firing. Clay is the longest-known ceramic material. Prehistoric humans discovered the useful properties of clay and used it for making pottery. Some of the earliest pottery shards have been radiocarbon dating, dated to around 14,000 BCE, and Clay tablet, clay tablets were the first known writing medium. Clay is used in many modern industrial processes, such as paper making, cement production, and chemical filtration, filtering. Between one-half and two-thirds of the world's population live or work in buildings made with clay, often baked into brick, as an essenti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delay Charge
Delay composition, also called delay charge or delay train, is a pyrotechnic composition, a sort of pyrotechnic initiator, a mixture of oxidizer and fuel that burns in a slow, constant rate that should not be significantly dependent on temperature and pressure. Delay compositions are used to introduce a delay into the firing train, e.g. to properly sequence firing of fireworks, to delay firing of ejection charges in e.g. model rockets, or to introduce a few seconds of time between triggering a hand grenade and its explosion. Typical delay times range between several milliseconds and several seconds. A popular delay charge is a tube of pressed black powder. The mechanical assembly prevents the outright detonation of the charge. While delay compositions are principally similar to other fuel-oxidizer compositions, larger grain sizes and less aggressively reacting chemicals are used. Many of the compositions generate little or no gas during burning. Typical materials used are: * Fuel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Powder
Gunpowder, also commonly known as black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur, charcoal (which is mostly carbon), and potassium nitrate, potassium nitrate (saltpeter). The sulfur and charcoal act as fuels while the saltpeter is an oxidizer. Gunpowder has been widely used as a propellant in firearms, artillery, rocketry, and pyrotechnics, including use as a blasting agent for explosives in quarrying, mining, building Pipeline transport, pipelines, tunnels, and road#Construction, roads. Gunpowder is classified as a Explosive#Low, low explosive because of its relatively slow decomposition rate, low ignition temperature and consequently low brisance, brisance (breaking/shattering). Low explosives deflagration, deflagrate (i.e., burn at subsonic speeds), whereas high explosives detonation, detonate, producing a supersonic shockwave. Ignition of gunpowder packed behind a projectile generates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrotechnic Star
Pyrotechnic stars are pellets of pyrotechnic composition which may contain metal powders, salts or other compounds that, when ignited, burn a certain color or make a certain spark effect. They are a part of all projectile-type fireworks. The most common is the aerial shell. When watching this firework, it will launch into the sky, burning a lifting charge. Once the shell has attained proper altitude, due to other mechanisms within the firework, it will ignite the stars. Procedure Stars are either rolled, pumped or cut. *Rolled stars are small cores of a hard material (often lead shot or an organic material such as mustard seeds or even cut stars) which are coated in a rotating mixer similar to a concrete mixer. First, water is sprayed on these cores. Then an amount of a pyrotechnic composition is placed into the mixer. As these two steps are repeated, the stars grow into a larger spherical shape. *Pumped stars are stars that have been pumped using a star pump. A dampened comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lifting Charge
Lift Powder, or Lift Charge is a slang term for Gunpowder. The term "Lift Powder" is mostly used in the Fireworks Fireworks are Explosive, low explosive Pyrotechnics, 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 numbe ... Industry. References {{DEFAULTSORT:Lift Powder Pyrotechnic compositions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bentonite
Bentonite ( ) is an Absorption (chemistry), absorbent swelling clay consisting mostly of montmorillonite (a type of smectite) which can either be Na-montmorillonite or Ca-montmorillonite. Na-montmorillonite has a considerably greater swelling capacity than Ca-montmorillonite. Bentonite usually forms from the weathering of volcanic ash in seawater, or by hydrothermal circulation through the porosity of volcanic ash beds, which converts (devitrification) the volcanic glass (obsidian, rhyolite, dacite) present in the ash into clay minerals. In the mineral alteration process, a large fraction (up to 40–50 wt.%) of amorphous silica is dissolution (chemistry), dissolved and leaching (agriculture), leached away, leaving the bentonite deposit in place. Bentonite beds are white or pale blue or green (traces of redox, reduced ) in fresh exposures, turning to a cream color and then yellow, red, or brown (traces of oxidation, oxidized ) as the exposure is weathered further. As a swel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roman Candle Jakarta NYE2020
Roman or Romans most often refers to: *Rome, the capital city of Italy *Ancient Rome, Roman civilization from 8th century BC to 5th century AD *Roman people, the people of Roman civilization *Epistle to the Romans, shortened to Romans, a letter written by Paul, found in the New Testament of the Christian Bible * Ar-Rum (), the 30th sura of the Quran. Roman or Romans may also refer to: Arts and entertainment Music * Romans (band), a Japanese pop group * ''Roman'' (album), by Sound Horizon, 2006 * ''Roman'' (EP), by Teen Top, 2011 *" Roman (My Dear Boy)", a 2004 single by Morning Musume Film and television *Film Roman, an American animation studio * ''Roman'' (film), a 2006 American suspense-horror film * ''Romans'' (2013 film), an Indian Malayalam comedy film * ''Romans'' (2017 film), a British drama film * ''The Romans'' (''Doctor Who''), a serial in British TV series People * Roman (given name), a given name, including a list of people and fictional characters *Roman (surname ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
