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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 the t ... [...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 its transmitter is located in Randleman, North Carolina. History WFMY's facility was the site of the first live television broadcast in the state of North Carolina on August 18, 1949, at 6:10 p.m. and officially signed on the air on September 22, 1949, as the second television station in North Carolina, debuting just a few months after fellow CBS affiliate WBTV in Charlotte. It was originally owned by the Greensboro News Company, publishers of the ''Greensboro Daily News'' and ''Daily Record'' (now merged as the ''Greensboro News & Record''). The News Company had put WFMY-FM on the air in 1948, but it shut the FM station down in 1953. A new radio station would be built by different owners in 1962 on an adjacent frequency, WQMG-F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comet (pyrotechnics)
In pyrotechnics a comet is a block attached to the outside of a shell or launched freely, 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 an astronomical object comprising a luminous spheroid of plasma held together by its gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night, but their immense distances from Earth ma ... 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 pieces to produce a branching effect. Comets intended for use indoors near an audience, such as at a rock concert, are typically freely-launched projectiles designed to completely consume themselves to reduce the hazard to audience members. File:Jeffhardyentrancepyrophilly.JPG, Jeff Hardy using the comet pyrote ... [...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 high-tech artillery. For rocket-propelled projectiles, internal ballistics covers the period during which a rocket motor is providing thrust. Parts and equations Hatcher breaks the duration of interior ballistics into three parts: *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. There are many processes that are significant. The source of energy is the burning propellant. It generates hot gases that raise the chambe ... [...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 Chinese between the 10th and 12th centuries. After the Chinese invented gunpowder, they began adapting its explosive properties for use in military technology ... [...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. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay particles, but become hard, brittle and non–plastic upon drying or firing. 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. Clay is the oldest 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 dated to around 14,000 BC, and clay tablets were the first known writing medium. Clay is used in many modern industrial processes, such as paper making, cement production, and chemical filtering. Between one-half and two-thirds of the world's population live or work in buildings made with clay, often ... [...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: * Fuels: ... [...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, carbon (in the form of charcoal) and potassium nitrate (saltpeter). The sulfur and carbon 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 pipelines and road building. Gunpowder is classified as a low explosive because of its relatively slow decomposition rate and consequently low brisance. Low explosives deflagrate (i.e., burn at subsonic speeds), whereas high explosives detonate, producing a supersonic shockwave. Ignition of gunpowder packed behind a projectile generates enough pressure to force the shot from the muzzle at high speed, but usually not enough force to rupture the gun barrel. It thus makes a good propellant but is ... [...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 some water is sprayed on cores. Then an amount of a pyrotechnic composition is dropped into the mixer. These two steps are repeated, and the stars will grow bigger and bigger into a spherical A sphere () is a geometrical object that is a three-dimensional ... [...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 a class of 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 l ... Industry. References {{DEFAULTSORT:Lift Powder Pyrotechnic compositions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bentonite
Bentonite () is an 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 dissolved and leached away, leaving the bentonite deposit in place. Bentonite beds are white or pale blue or green (traces of reduced ) in fresh exposures, turning to a cream color and then yellow, red, or brown (traces of oxidized ) as the exposure is weathered further. As a swelling clay, bentonite has the ability to absorb large quantities of water, which increa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roman Candle Structure Drawing-en
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 ancient Rome *''Epistle to the Romans'', shortened to ''Romans'', a letter in the New Testament of the Christian Bible 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), including a list of people named Roman or Romans *Ῥωμαῖ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
