Matches in DBpedia 2016-04 for { <http://wikidata.dbpedia.org/resource/Q12861> ?p ?o }
- Q12861 subject Q10798683.
- Q12861 subject Q5863686.
- Q12861 subject Q6009239.
- Q12861 subject Q7008737.
- Q12861 subject Q7008797.
- Q12861 subject Q7216223.
- Q12861 subject Q8459796.
- Q12861 abstract "Gunpowder, also known as black powder, is the earliest known chemical explosive. It is a mixture of sulfur, charcoal, and potassium nitrate (saltpeter). The sulfur and charcoal act as fuels, and the saltpeter is an oxidizer. Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks. Formulations used in blasting rock (such as in quarrying) are called blasting powder. Gunpowder is mainly used in older guns now because the propellants used today are too powerful and could break the already fragile barrels.The key to gunpowder is the fact that saltpeter gives off oxygen in certain chemical reactions. This means that gunpowder will burn without an external air supply. If you light a heap of gunpowder it burns rapidly and gives off a great deal of smoke and hot gas. If you put gunpowder in a paper container and light it the hot gas builds up until the paper bursts, making a firecracker. If you put gunpowder a metal container and light it the hot gas builds up a great deal of pressure before bursting the container and throwing fragments in all directions. This is a bomb. If you put gunpower in a bamboo tube and light it smoke and fire come out one end, making a fire lance which can be used as a weapon. If you plug up the tube the hot gas eventually expels the plug, which is the basis of the gun. The expelled gas forces the tube backwards, which is the basis if the rocket. All of these things were invented in China.Gunpowder was, according to prevailing academic consensus, invented in the 9th century in China, and the earliest record of a written formula for gunpowder appears in the 11th century Song dynasty text, Wujing Zongyao. This discovery led to the invention of fireworks and the earliest gunpowder weapons in China. In the centuries following the Chinese discovery, gunpowder weapons began appearing in the Muslim world, Europe, and India. The technology spread from China through the Middle East or Central Asia, and then into Europe. The earliest Western accounts of gunpowder appear in texts written by English philosopher Roger Bacon in the 13th century.Gunpowder is assigned the UN number UN0027 and has a hazard class of 1.1D. It has a flash point of approximately 427–464 °C (801–867 °F). The specific flash point may vary based on the specific composition of the gunpowder. Gunpowder's specific gravity is 1.70–1.82 (mercury method) or 1.92–2.08 (pycnometer), and it has a pH of 6.0–8.0. It is also considered to be an insoluble material.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 wave.Gunpowder's burning rate increases with pressure, so it will burst containers but just burns in the open. Ignition of the powder packed behind a bullet must generate enough pressure to force it from the muzzle at high speed, but not enough to rupture the gun barrel. Gunpowder thus makes a good propellant, but is less suitable for shattering rock or fortifications. Gunpowder was widely used to fill artillery shells and in mining and civil engineering to blast rock roughly until the second half of the 19th century, when the first high explosives (nitro-explosives) were devised and formulated. Gunpowder is no longer used in modern explosive military warheads, nor is it used as main explosive in mining operations due to its cost relative to that of newer alternatives such as ammonium nitrate/fuel oil (ANFO). Black powder is still used as a delay element in various munitions where its slow-burning properties are valuable.".
- Q12861 thumbnail Black_Powder_Close_Up.jpg?width=300.
- Q12861 wikiPageExternalLink search?site=default_collection&q=black+powder&btnG.x=-1050&btnG.y=-126&btnG=Google+Search&client=dticol_frontend&proxystylesheet=dticol_frontend&proxyreload=1&filter=0&tlen=200&getfields=*.
- Q12861 wikiPageExternalLink cannon.htm.
- Q12861 wikiPageExternalLink www.history-science-technology.com.
- Q12861 wikiPageExternalLink articles%202.htm.
- Q12861 wikiPageExternalLink history.html.
- Q12861 wikiPageExternalLink 244083392_Chemistry_and_Technology_of_Explosives_Vol._III_by_Tadeusz_Urbaski_Pergamon-PWN_Polish_Scientific_Publishers_Warszawa_1967_717_pages__7.10.0d_(23.00).
- Q12861 wikiPageExternalLink 817.extract.
- Q12861 wikiPageExternalLink Needham_Joseph_Science_and_Civilisation_in_China_Vol_7-2_General_Conclusions_and_Reflections.pdf.
- Q12861 wikiPageExternalLink 41.1roland.html.
- Q12861 wikiPageExternalLink 49.3.bachrach.html.
- Q12861 wikiPageExternalLink gun-powder-demonstration.
- Q12861 wikiPageExternalLink 6291240?selectedversion=NBD14331705.
- Q12861 wikiPageExternalLink explosive.
- Q12861 wikiPageExternalLink www.gunpowderworks.co.uk.
- Q12861 wikiPageExternalLink index.html.
- Q12861 wikiPageExternalLink 40109543.
- Q12861 wikiPageExternalLink recipe.html.
- Q12861 wikiPageExternalLink www.royalgunpowdermills.com.
- Q12861 wikiPageExternalLink gun.shtml.
- Q12861 wikiPageExternalLink BentonJames-1862.
- Q12861 wikiPageExternalLink gporigins.html&date=2009-10-25+05:32:43.
- Q12861 wikiPageExternalLink dangerous-energy.
- Q12861 wikiPageWikiLink Q10088.
- Q12861 wikiPageWikiLink Q1017175.
- Q12861 wikiPageWikiLink Q102769.
- Q12861 wikiPageWikiLink Q1058629.
- Q12861 wikiPageWikiLink Q1061.
- Q12861 wikiPageWikiLink Q1065.
- Q12861 wikiPageWikiLink Q10798683.
- Q12861 wikiPageWikiLink Q10972285.
- Q12861 wikiPageWikiLink Q109746.
- Q12861 wikiPageWikiLink Q10987.
- Q12861 wikiPageWikiLink Q1106331.
- Q12861 wikiPageWikiLink Q11162356.
- Q12861 wikiPageWikiLink Q11183742.
- Q12861 wikiPageWikiLink Q11190.
- Q12861 wikiPageWikiLink Q1124327.
- Q12861 wikiPageWikiLink Q11427.
- Q12861 wikiPageWikiLink Q1148444.
- Q12861 wikiPageWikiLink Q11570.
- Q12861 wikiPageWikiLink Q1182714.
- Q12861 wikiPageWikiLink Q1194773.
- Q12861 wikiPageWikiLink Q12099.
- Q12861 wikiPageWikiLink Q127197.
- Q12861 wikiPageWikiLink Q12757.
- Q12861 wikiPageWikiLink Q127933.
- Q12861 wikiPageWikiLink Q12796.
- Q12861 wikiPageWikiLink Q12870.
- Q12861 wikiPageWikiLink Q12892.
- Q12861 wikiPageWikiLink Q130327.
- Q12861 wikiPageWikiLink Q1316061.
- Q12861 wikiPageWikiLink Q132298.
- Q12861 wikiPageWikiLink Q1324245.
- Q12861 wikiPageWikiLink Q132851.
- Q12861 wikiPageWikiLink Q133235.
- Q12861 wikiPageWikiLink Q13424364.
- Q12861 wikiPageWikiLink Q1344031.
- Q12861 wikiPageWikiLink Q1353.
- Q12861 wikiPageWikiLink Q1354.
- Q12861 wikiPageWikiLink Q1364934.
- Q12861 wikiPageWikiLink Q137056.
- Q12861 wikiPageWikiLink Q138937.
- Q12861 wikiPageWikiLink Q142.
- Q12861 wikiPageWikiLink Q1424040.
- Q12861 wikiPageWikiLink Q1430251.
- Q12861 wikiPageWikiLink Q145.
- Q12861 wikiPageWikiLink Q146136.
- Q12861 wikiPageWikiLink Q1461850.
- Q12861 wikiPageWikiLink Q1464982.
- Q12861 wikiPageWikiLink Q1469447.
- Q12861 wikiPageWikiLink Q14975330.
- Q12861 wikiPageWikiLink Q1503383.
- Q12861 wikiPageWikiLink Q15432539.
- Q12861 wikiPageWikiLink Q156.
- Q12861 wikiPageWikiLink Q156212.
- Q12861 wikiPageWikiLink Q160066.
- Q12861 wikiPageWikiLink Q16062995.
- Q12861 wikiPageWikiLink Q161205.
- Q12861 wikiPageWikiLink Q1645059.
- Q12861 wikiPageWikiLink Q16746543.
- Q12861 wikiPageWikiLink Q16821449.
- Q12861 wikiPageWikiLink Q16931406.
- Q12861 wikiPageWikiLink Q16957.
- Q12861 wikiPageWikiLink Q16984320.
- Q12861 wikiPageWikiLink Q170167.
- Q12861 wikiPageWikiLink Q1703941.
- Q12861 wikiPageWikiLink Q170591.
- Q12861 wikiPageWikiLink Q171677.
- Q12861 wikiPageWikiLink Q173366.
- Q12861 wikiPageWikiLink Q173517.
- Q12861 wikiPageWikiLink Q17504814.