|
Fire
Fire is the rapid oxidation of a material (the fuel) in the exothermic chemical process of combustion, releasing heat, light, and various reaction Product (chemistry), products. At a certain point in the combustion reaction, called the ignition point, flames are produced. The ''flame'' is the visible portion of the fire. Flames consist primarily of carbon dioxide, water vapor, oxygen and nitrogen. If hot enough, the gases may become ionized to produce Plasma (physics), plasma. Depending on the substances alight, and any impurities outside, the color of the flame and the fire's Intensity (heat transfer), intensity will be different. Fire in its most common form can result in conflagration, which has the potential to cause physical damage through burning. Fire is an important process that affects ecological systems around the globe. The positive effects of fire include stimulating growth and maintaining various ecological systems. Its negative effects include hazard to life and pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conflagration
A conflagration is a large fire. Conflagrations often damage human life, animal life, health, and/or property. A conflagration can begin accidentally, be naturally caused (wildfire), or intentionally created (arson). A very large fire can produce a firestorm, in which the central column of rising heated air induces strong inward winds, which supply oxygen to the fire. Conflagrations can cause casualties including deaths or injuries from burns, trauma due to collapse of structures and attempts to escape, and smoke inhalation. Firefighting is the practice of extinguishing a conflagration, protecting life and property and minimizing damage and injury. One of the goals of fire prevention is to avoid conflagrations. When a conflagration is extinguished, there is often a fire investigation to determine the cause of the fire. Causes and types During a conflagration a significant movement of air and combustion products occurs. Hot gaseous products of combustion move upward, causin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fire (classical Element)
Fire is one of the four classical elements along with earth, water and air in ancient Greek philosophy and science. Fire is considered to be both hot and dry and, according to Plato, is associated with the tetrahedron. Greek and Roman tradition Fire is one of the four classical elements in ancient Greek philosophy and science. It was commonly associated with the qualities of energy, assertiveness, and passion. In one Greek myth, Prometheus stole ''fire'' from the gods to protect the otherwise helpless humans, but was punished for this charity. Fire was one of many '' archai'' proposed by the pre-Socratics, most of whom sought to reduce the cosmos, or its creation, to a single substance. Heraclitus considered ''fire'' to be the most fundamental of all elements. He believed fire gave rise to the other three elements: "All things are an interchange for fire, and fire for all things, just like goods for gold and gold for goods." Diels-Kranz B90 (Freeman 9481970p. 45. He had a repu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fire Worship
Worship or deification of fire (also pyrodulia, pyrolatry or pyrolatria) is known from various religions. Fire has been an important part of human culture since the Lower Paleolithic. Religious or animist notions connected to fire are assumed to reach back to such early pre-''Homo sapiens'' times. Indo-European religions In Indo-European languages, there were two concepts regarding fire: that of an animate type called *''h₁n̥gʷnís'' (cf. Sanskrit ''agni'', English ''ignite'' from Latin ''ignis'', Polish ''ogień'' and Russian ''ogon''), and an inanimate type *''péh₂wr̥'' (cf. English ''fire'', Greek ''pyr'', Sanskrit ''pu''). A similar distinction existed for water. Archaeologically, evidence for Indo-Iranian fire worship and the rite of cremation is found at the transition from the Sintashta-Petrovka to the Andronovo culture around 1500 BC. Fire worship was prevalent in Vedic and the Ancient Iranian religion. Whereas cremation became ubiquitous in Hinduism, it was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bonfire
A bonfire is a large and controlled outdoor fire, used either for informal disposal of burnable waste material or as part of a celebration. Etymology The earliest recorded uses of the word date back to the late 15th century, with the Catholicon Anglicum spelling it as ''banefyre'' and John Mirk's ''Book of Festivals'' speaking of a communal fire in celebrations of Saint John's Eve that "was clene bones & no wode & that is callid a bone fyre". The word is thus a compound of "bone" and "fire." In 1755, Samuel Johnson misattributed the origin of the word as a compound of the French "''bon''" (“good”) and the English "fire" in A Dictionary of the English Language. Regional traditions In many regions of continental Europe, bonfires are made traditionally on 24 June, the solemnity of John the Baptist, as well as on Saturday night before Easter. Bonfires are also a feature of Walpurgis Night in central and northern Europe, and Bonfires of Saint John, the celebrations on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guy Fawkes Night
Guy Fawkes Night, also known as Guy Fawkes Day, Bonfire Night and Fireworks Night, is an annual commemoration observed on 5 November, primarily in Great Britain, involving bonfires and fireworks displays. Its history begins with the events of 5 November 1605 O.S., when Guy Fawkes, a member of the Gunpowder Plot, was arrested while guarding explosives the plotters had placed beneath the House of Lords. The Catholic plotters had intended to assassinate Protestant king James I and his parliament. Celebrating that the king had survived, people lit bonfires around London; and months later, the Observance of 5th November Act mandated an annual public day of thanksgiving for the plot's failure. Within a few decades Gunpowder Treason Day, as it was known, became the predominant English state commemoration. As it carried strong Protestant religious overtones it also became a focus for anti-Catholic sentiment. Puritans delivered sermons regarding the perceived dangers of p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flame
A flame (from Latin ''flamma'') is the visible, gaseous part of a fire. It is caused by a highly exothermic chemical reaction taking place in a thin zone. When flames are hot enough to have ionized gaseous components of sufficient density they are then considered plasma. Mechanism Color and temperature of a flame are dependent on the type of fuel involved in the combustion, as, for example, when a lighter is held to a candle. The applied heat causes the fuel molecules in the candle wax to vaporize (if this process happens in inert atmosphere without oxidizer, it is called pyrolysis). In this state they can then readily react with oxygen in the air, which gives off enough heat in the subsequent exothermic reaction to vaporize yet more fuel, thus sustaining a consistent flame. The high temperature of the flame causes the vaporized fuel molecules to decompose, forming various incomplete combustion products and free radicals, and these products then react with each other and with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burning
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion does not always result in fire, because a flame is only visible when substances undergoing combustion vaporize, but when it does, a flame is a characteristic indicator of the reaction. While the activation energy must be overcome to initiate combustion (e.g., using a lit match to light a fire), the heat from a flame may provide enough energy to make the reaction self-sustaining. Combustion is often a complicated sequence of elementary radical reactions. Solid fuels, such as wood and coal, first undergo endothermic pyrolysis to produce gaseous fuels whose combustion then supplies the heat required to produce more of them. Combustion is often hot enough that incandescent light in the form of either glowing or a flame is produced. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combustion
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion does not always result in fire, because a flame is only visible when substances undergoing combustion vaporize, but when it does, a flame is a characteristic indicator of the reaction. While the activation energy must be overcome to initiate combustion (e.g., using a lit match to light a fire), the heat from a flame may provide enough energy to make the reaction self-sustaining. Combustion is often a complicated sequence of elementary radical reactions. Solid fuels, such as wood and coal, first undergo endothermic pyrolysis to produce gaseous fuels whose combustion then supplies the heat required to produce more of them. Combustion is often hot enough that incandescent light in the form of either glowing or a flame is produced. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuel
A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. The concept was originally applied solely to those materials capable of releasing chemical energy but has since also been applied to other sources of heat energy, such as nuclear energy (via nuclear fission and nuclear fusion). The heat energy released by reactions of fuels can be converted into mechanical energy via a heat engine. Other times, the heat itself is valued for warmth, cooking, or industrial processes, as well as the illumination that accompanies combustion. Fuels are also used in the cells of organisms in a process known as cellular respiration, where organic molecules are oxidized to release usable energy. Hydrocarbons and related organic molecules are by far the most common source of fuel used by humans, but other substances, including radioactive metals, are also utilized. Fuels are contrasted with other substances or de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasma (physics)
Plasma () 1, where \nu_ is the electron gyrofrequency and \nu_ is the electron collision rate. It is often the case that the electrons are magnetized while the ions are not. Magnetized plasmas are ''anisotropic'', meaning that their properties in the direction parallel to the magnetic field are different from those perpendicular to it. While electric fields in plasmas are usually small due to the plasma high conductivity, the electric field associated with a plasma moving with velocity \mathbf in the magnetic field \mathbf is given by the usual Lorentz force, Lorentz formula \mathbf = -\mathbf\times\mathbf, and is not affected by Debye shielding. Mathematical descriptions To completely describe the state of a plasma, all of the particle locations and velocities that describe the electromagnetic field in the plasma region would need to be written down. However, it is generally not practical or necessary to keep track of all the particles in a plasma. Therefore, plasma physicist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lightning
Lightning is a naturally occurring electrostatic discharge during which two electric charge, electrically charged regions, both in the atmosphere or with one on the land, ground, temporarily neutralize themselves, causing the instantaneous release of an average of one Joule, gigajoule of energy. This discharge may produce a wide range of electromagnetic radiation, from heat created by the rapid movement of electrons, to brilliant flashes of visible light in the form of black-body radiation. Lightning causes thunder, a sound from the shock wave which develops as gases in the vicinity of the discharge experience a sudden increase in pressure. Lightning occurs commonly during thunderstorms as well as other types of energetic weather systems, but volcanic lightning can also occur during volcanic eruptions. The three main kinds of lightning are distinguished by where they occur: either inside a single Cumulonimbus cloud, thundercloud (intra-cloud), between two clouds (cloud-to-cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, that is easily removed to create an ion with a positive charge – a cation, that combines with anions to form salts. Potassium in nature occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in the reaction, and burning with a lilac- colored flame. It is found dissolved in sea water (which is 0.04% potassium by weight), and occurs in many minerals such as orthoclase, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
