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Fire Retardant
A fire retardant is a substance that is used to slow down or stop the spread of fire or reduce its intensity. This is commonly accomplished by chemical reactions that reduce the flammability of fuels or delay their combustion. Fire retardants may also cool the fuel through physical action or endothermic chemical reactions. Fire retardants are available as powder, to be mixed with water, as fire-fighting foams and fire-retardant gels. Fire retardants are commonly used in fire fighting, where they may be applied aerially or from the ground. Principles of operation In general, fire retardants reduce the flammability of materials by either blocking the fire physically or by initiating a chemical reaction that stops the fire. Physical action There are several ways in which the combustion process can be retarded by physical action: * By cooling: Some chemical reactions actually cool the material down. * By forming a protective layer that prevents the underlying material from i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminium Hydroxide
Aluminium hydroxide, , is found as the mineral gibbsite (also known as hydrargillite) and its three much rarer polymorphs: bayerite, doyleite, and nordstrandite. Aluminium hydroxide is amphoteric, i.e., it has both basic and acidic properties. Closely related are aluminium oxide hydroxide, AlO(OH), and aluminium oxide or alumina (), the latter of which is also amphoteric. These compounds together are the major components of the aluminium ore bauxite. Aluminium hydroxide also forms a gelatinous precipitate in water. Structure is built up of double layers of hydroxyl groups with aluminium ions occupying two-thirds of the octahedral holes between the two layers. Four polymorphs are recognized. All feature layers of octahedral aluminium hydroxide units, with hydrogen bonds between the layers. The polymorphs differ in terms of the stacking of the layers. All forms of crystals are hexagonal : * gibbsite is also known as γ- or α- * bayerite is also known as α- or ''β ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tumbleweed Fire, Los Angeles County 2021, Part 9
A tumbleweed is a structural part of the above-ground anatomy of a number of species of plants. It is a Diaspore (botany), diaspore that, once mature and dry, Abscission, detaches from its root or stem and Rotating locomotion in living systems, rolls due to the force of the wind. In most such species, the tumbleweed is in effect the entire plant apart from the root system, but in other plants, a hollow fruit or inflorescence might detach instead. Xerophyte tumbleweed species occur most commonly in steppe and arid ecosystems, where frequent wind and the open environment permit rolling without prohibitive obstruction. Apart from its primary vascular system and roots, the tissues of the tumbleweed structure are dead; their death is functional because it is necessary for the structure to degrade gradually and fall apart so that its seeds or spores can escape during the tumbling, or germinate after the tumbleweed has come to rest in a moist location. In the latter case, many species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminum Oxide
Aluminium oxide (or aluminium(III) oxide) is a chemical compound of aluminium and oxygen with the chemical formula . It is the most commonly occurring of several aluminium oxides, and specifically identified as aluminium oxide. It is commonly called alumina and may also be called aloxide, aloxite, ALOX or alundum in various forms and applications and alumina is refined from bauxite. It occurs naturally in its crystalline polymorphic phase α-Al2O3 as the mineral corundum, varieties of which form the precious gemstones ruby and sapphire,which have an alumina content approaching 100%. Al2O3 is used as feedstock to produce aluminium metal, as an abrasive owing to its hardness, and as a refractory material owing to its high melting point. Natural occurrence Corundum is the most common naturally occurring crystalline form of aluminium oxide. Rubies and sapphires are gem-quality forms of corundum, which owe their characteristic colours to trace impurities. Rubies are given their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plastic Additive
Plastics are a wide range of synthetic or semisynthetic materials composed primarily of polymers. Their defining characteristic, plasticity, allows them to be molded, extruded, or pressed into a diverse range of solid forms. This adaptability, combined with a wide range of other properties such as low weight, durability, flexibility, chemical resistance, low toxicity, and low-cost production, has led to their widespread use around the world. While most plastics are produced from natural gas and petroleum, a growing minority are produced from renewable resources like polylactic acid. Between 1950 and 2017, 9.2 billion metric tons of plastic are estimated to have been made, with more than half of this amount being produced since 2004. In 2023 alone, preliminary figures indicate that over 400 million metric tons of plastic were produced worldwide. If global trends in plastic demand continue, it is projected that annual global plastic production will exceed 1.3 billion tons by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Insulation
Thermal insulation is the reduction of heat transfer (i.e., the transfer of thermal energy between objects of differing temperature) between objects in thermal contact or in range of radiative influence. Thermal insulation can be achieved with specially engineered methods or processes, as well as with suitable object shapes and materials. Heat flow is an inevitable consequence of contact between objects of different temperature. Thermal insulation provides a region of insulation in which thermal conduction is reduced, creating a thermal break or thermal barrier, or thermal radiation is reflected rather than absorbed by the lower-temperature body. The insulating capability of a material is measured as the inverse of thermal conductivity, thermal conductivity (k). Low thermal conductivity is equivalent to high insulating capability (R-value (insulation), resistance value). In thermal engineering, other important properties of insulating materials are product density, density (ρ) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intumescent
An intumescent substance is one that swells as a result of heat exposure, leading to an increase in volume and decrease in density. Intumescence refers to the process of swelling. Intumescent materials are typically used in passive fire protection and require listing and approval use and compliance, listing, approval, and compliance in their installed configurations in order to comply with the national building codes and laws. The details for individual building parts are specified in technical standards which are compiled and published by national or international standardization bodies like the BSI Group, British Standards Institute (BSI), the Deutsches Institut für Normung, German Institute for Standardization (DIN), the ASTM International, American Society for Testing and Materials (ASTM) or the International Organization for Standardization (ISO). Intumescent coatings for steel constructions must be approved in standardized fire tests. Types Soft char These intumescent ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon
Carbon () is a chemical element; it has chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 electrons. It belongs to group 14 of the periodic table. Carbon makes up about 0.025 percent of Earth's crust. Three Isotopes of carbon, isotopes occur naturally, carbon-12, C and carbon-13, C being stable, while carbon-14, C is a radionuclide, decaying with a half-life of 5,700 years. Carbon is one of the timeline of chemical element discoveries#Pre-modern and early modern discoveries, few elements known since antiquity. Carbon is the 15th abundance of elements in Earth's crust, most abundant element in the Earth's crust, and the abundance of the chemical elements, fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen. Carbon's abundance, its unique diversity of organic compounds, and its unusual abi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Char (chemistry)
Char is the solid material that remains after light gases (e.g. coal gas) and tar have been driven out or released from a carbonaceous material during the initial stage of combustion, which is known as carbonization, charring, devolatilization or pyrolysis. Further stages of efficient combustion (with or without char deposits) are known as gasification reactions, ending quickly when the reversible gas phase of the water gas shift reaction is reached. See also * Biochar * Charcoal * Coke (fuel) * Petroleum coke Petroleum coke, abbreviated coke, pet coke or petcoke, is a final carbon-rich solid material that derives from oil refinery, oil refining, and is one type of the group of fuels referred to as Coke (fuel), cokes. Petcoke is the coke that, in parti ... * Shale oil extraction * Spent shale References Oil shale Coal {{hydrocarbon-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plastic
Plastics are a wide range of synthetic polymers, synthetic or Semisynthesis, semisynthetic materials composed primarily of Polymer, polymers. Their defining characteristic, Plasticity (physics), plasticity, allows them to be Injection moulding, molded, Extrusion, extruded, or Compression molding, pressed into a diverse range of solid forms. This adaptability, combined with a wide range of other properties such as low weight, durability, flexibility, chemical resistance, low toxicity, and low-cost production, has led to their widespread use around the world. While most plastics are produced from natural gas and petroleum, a growing minority are produced from renewable resources like polylactic acid. Between 1950 and 2017, 9.2 billion metric tons of plastic are estimated to have been made, with more than half of this amount being produced since 2004. In 2023 alone, preliminary figures indicate that over 400 million metric tons of plastic were produced worldwide. If global trends ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymer
A polymer () is a chemical substance, substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeat unit, repeating subunits derived from one or more species of monomers. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compound (chemistry), compounds, produces unique physical property, physical properties including toughness, high rubber elasticity, elasticity, viscoelasticity, and a tendency to form Amorphous solid, amorphous and crystallization of polymers, semicrystalline structures rath ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PhostrEx
PhostrEx is a fire suppression agent developed for use in aviation applications to replace halon, a greenhouse gas (GHG). It was developed by Eclipse Aviation for use aboard their Eclipse 500 very light jets as an engine fire suppression system, and is now being marketed to other aviation manufacturers. Overview The PhostrEx fire suppression system addresses many of the problems with halon, from system weight to environmental concerns. These concerns, including halon's ozone-depleting and global warming characteristics, prompted the Montreal Protocol to outlaw its use. The only exception allowed by this international treaty was in aviation applications, and only until a suitable replacement became available. PhostrEx meets the requirements of both the Montreal Protocol and the Clean Air Act, and is the first commercially viable Federal Aviation Administration and United States Environmental Protection Agency certified halon replacement fire extinguishing agent. The EPA awarded th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
