|
Colofonia
Rosin (), also known as colophony or Greek pitch (), is a resinous material obtained from pine trees and other plants, mostly conifers. The primary components of rosin are diterpenoids, i.e., C20 carboxylic acids. Rosin consists mainly of resin acids, especially abietic acid. Rosin often appears as a semi-transparent, brittle substance that ranges in color from yellow to black and melts at stove-top temperatures. In addition to industrial applications such as in varnishes, adhesives, and sealing wax, rosin is used with string instruments on the bow hair to enhance its ability to grip and sound the strings, and it provides grip in various sports and activities. Rosin also serves as an ingredient in medicinal and pharmaceutical formulations and can cause contact dermatitis or occupational asthma in sensitive individuals. It is an FDA approved food additive. The name "colophony" originates from , Latin for "resin from Colophon" (), an ancient Ionic city. Properties Rosin is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maison Du Patrimoine De Mimizan Colophane 2
Maison (French for "house") may refer to: People * Edna Maison (1892–1946), American silent-film actress * Jérémy Maison (born 1993), French cyclist * Leonard Maison, New York state senator 1834–1837 * Nicolas Joseph Maison (1771–1840), Marshal of France and Minister of War * René Maison (1895–1962), Belgian operatic tenor * Rudolf Maison (1854–1904), German sculptor Places in France * Maison-des-Champs, a commune in the Aube department, Grand Est * Maison-Feyne, a commune in the Creuse department, Nouvelle-Aquitaine * Maison-Maugis, a former commune in the Orne department, Normandy * Maison-Ponthieu, a commune in the Somme department, Hauts-de-France * Maison-Roland, a commune in the Somme department, Hauts-de-France * Maison-Rouge, a commune in the Seine-et-Marne department, Île-de-France Music Songs * "Maison", by Dreamcatcher from ''Apocalypse: Save Us'' See also * Valérie Grand'Maison (born 1988), Canadian Paralympic swimmer * Zoé De Grand Maison (born ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brittle
A material is brittle if, when subjected to stress, it fractures with little elastic deformation and without significant plastic deformation. Brittle materials absorb relatively little energy prior to fracture, even those of high strength. Breaking is often accompanied by a sharp snapping sound. When used in materials science, it is generally applied to materials that fail when there is little or no plastic deformation before failure. One proof is to match the broken halves, which should fit exactly since no plastic deformation has occurred. Brittleness in different materials Polymers Mechanical characteristics of polymers can be sensitive to temperature changes near room temperatures. For example, poly(methyl methacrylate) is extremely brittle at temperature 4˚C, but experiences increased ductility with increased temperature. Amorphous polymers are polymers that can behave differently at different temperatures. They may behave like a glass at low temperatures (the gla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caulking
Caulk (also known as caulking and calking) is a material used to seal joints or seams against leakage in various structures and piping. The oldest form of caulk consisted of fibrous materials driven into the wedge-shaped seams between boards on wooden boats or ships. Cast iron sewerage pipes were formerly caulked in a similar way. Riveted seams in ships and boilers were formerly sealed by hammering the metal. Modern caulking compounds are flexible sealing compounds used to close up gaps in buildings and other structures against water, air, dust, insects, or as a component in firestopping. In the tunneling industry, caulking is the sealing of joints in segmental precast concrete tunnels, commonly by using concrete. Historical uses Wooden shipbuilding Traditional caulking (also spelled calking) on wooden vessels uses fibers of cotton and oakum (hemp) soaked in pine tar. These fibers are driven into the wedge-shaped seam between planks, with a caulking mallet and a broad ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bowed String Instrument
Bowed string instruments are a subcategory of string instruments that are played by a bow (music), bow rubbing the string (music), strings. The bow rubbing the string causes vibration which the instrument emits as sound. Despite the numerous specialist studies devoted to the origin of bowing, the Bow (music)#Origin, origin of bowing remains unknown.Friedrich Behn, Musikleben im Altertum und frühen page 159 List of bowed string instruments Violin family * Cello (violoncello) * Pochette (musical instrument), Pochette * Viola (altviol, bratsche) * Violin (violino) * Double bass (contrabasso) ;Variants on the standard members of the violin family include: * Baroque violin * Cello da spalla * Five string violin * Hardanger fiddle * Kit violin * Kontra * Låtfiol * Lira da braccio * Octobass * Sardino * Stroh violin * Tenor violin Viol family (Viola da Gamba family) * Viol, Alto viol * Viol, Bass viol * Viol, Tenor viol * Viol, Treble viol ;Variants on the standard ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bow (music)
In music, a bow () is a tensioned stick which has hair (usually horse-tail hair) coated in rosin (to facilitate friction) affixed to it. It is moved across some part (generally some type of strings) of a musical instrument to cause vibration, which the instrument emits as sound. The vast majority of bows are used with string instruments, such as the violin, viola, cello, and bass, although some bows are used with musical saws and other bowed idiophones. Materials and manufacture A bow consists of a specially shaped stick with other material forming a ribbon stretched between its ends, which is used to stroke the string and create sound. Different musical cultures have adopted various designs for the bow. For instance, in some bows a single cord is stretched between the ends of the stick. In the Western tradition of bow making—bows for the instruments of the violin and viol families—a hank of horsehair is normally employed. The manufacture of bows is considered a demandi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abietic Acid
Abietic acid (also known as ''abietinic acid'' or ''sylvic acid'') is a diterpenoid found in coniferous trees. It is supposed to exist to defend the host plant from insect attack or various wounds. Chemically, it is a complicated molecule featuring two alkene groups and a carboxylic acid within a chiral tricyclic framework. As the major component of rosin, it is commercially important. Historically speaking, it was a major component of naval stores. It is the most common of the resin acids. Another common resin acid is pimaric acid, which converts to abietic acid upon heating. Characteristics and occurrence Abietic acid is found in rosin obtained from pine trees. Pure abietic acid is a colorless solid, but commercial samples are usually a glassy or partly crystalline yellowish solid that melts at temperatures as low as . Abietic acid is soluble in alcohols, acetone, and ethers. Its esters and salts are called an abietates, e.g. ethyl abietate and sodium abietate.Lars-Hugo Norlin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soap Making
Soap is a salt of a fatty acid (sometimes other carboxylic acids) used for cleaning and lubricating products as well as other applications. In a domestic setting, soaps, specifically "toilet soaps", are surfactants usually used for washing, bathing, and other types of housekeeping. In industrial settings, soaps are used as thickeners, components of some lubricants, emulsifiers, and catalysts. Soaps are often produced by mixing fats and oils with a base. Humans have used soap for millennia; evidence exists for the production of soap-like materials in ancient Babylon around 2800 BC. Types Toilet soaps In a domestic setting, "soap" usually refers to what is technically called a toilet soap, used for household and personal cleaning. Toilet soaps are salts of fatty acids with the general formula ( RCO2−)M+, where M is Na (sodium) or K (potassium). When used for cleaning, soap solubilizes particles and grime, which can then be separated from the article being cleaned. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkali
In chemistry, an alkali (; from the Arabic word , ) is a basic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The adjective alkaline, and less often, alkalescent, is commonly used in English as a synonym for basic, especially for bases soluble in water. This broad use of the term is likely to have come about because alkalis were the first bases known to obey the Arrhenius definition of a base, and they are still among the most common bases. Etymology The word ''alkali'' is derived from Arabic ''al qalīy'' (or ''alkali''), meaning (see calcination), referring to the original source of alkaline substances. A water-extract of burned plant ashes, called potash and composed mostly of potassium carbonate, was mildly basic. After heating this substance with calcium hydroxide (''slaked lime''), a far more strongly basic substance known as ''caustic potash ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloroform
Chloroform, or trichloromethane (often abbreviated as TCM), is an organochloride with the formula and a common solvent. It is a volatile, colorless, sweet-smelling, dense liquid produced on a large scale as a precursor to refrigerants and polytetrafluoroethylene (PTFE). Chloroform was once used as an inhalational anesthetic between the 19th century and the first half of the 20th century. It is miscible with many solvents but it is only very slightly soluble in water (only 8 g/L at 20°C). Structure and name The molecule adopts a tetrahedral molecular geometry with C3v symmetry. The chloroform molecule can be viewed as a methane molecule with three hydrogen atoms replaced with three chlorine atoms, leaving a single hydrogen atom. The name "chloroform" is a portmanteau of ''terchloride'' (tertiary chloride, a trichloride) and ''formyle'', an obsolete name for the methylylidene radical (CH) derived from formic acid. Natural occurrence Many kinds of seaweed produce chlor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzene
Benzene is an Organic compound, organic chemical compound with the Chemical formula#Molecular formula, molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar hexagonal Ring (chemistry), ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon. Benzene is a natural constituent of petroleum and is one of the elementary petrochemicals. Due to the cyclic continuous pi bonds between the carbon atoms, benzene is classed as an aromatic hydrocarbon. Benzene is a colorless and highly Combustibility and flammability, flammable liquid with a sweet smell, and is partially responsible for the aroma of gasoline. It is used primarily as a Precursor (chemistry), precursor to the manufacture of chemicals with more complex structures, such as ethylbenzene and cumene, of which billions of kilograms are produced annually. Although benzene is a major Chemical industry, industrial che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethyl Ether
Diethyl ether, or simply ether, is an organic compound with the chemical formula , sometimes abbreviated as . It is a colourless, highly Volatility (chemistry), volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It belongs to the ether class of organic compounds. It is a common solvent and was formerly used as a general anesthetic. Production Most diethyl ether is produced as a byproduct of the vapor-phase Hydration reaction, hydration of ethylene to make ethanol. This process uses solid-supported phosphoric acid Catalysis, catalysts and can be adjusted to make more ether if the need arises: Vapor-phase Dehydration reaction, dehydration of ethanol over some Aluminium oxide, alumina catalysts can give diethyl ether yields of up to 95%. : Diethyl ether can be prepared both in laboratories and on an industrial scale by the acid ether synthesis. Uses The dominant use of diethyl ether is as a solvent. One particular application is in the production of cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethanol
Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the pseudoelement symbol for ethyl group, ethyl. Ethanol is a Volatility (chemistry), volatile, flammable, colorless liquid with a characteristic wine-like odor and pungent taste. As a psychoactive depressant, it is the active ingredient in alcoholic beverages, and the second most consumed drug globally behind caffeine. Ethanol is naturally produced by the fermentation process of sugars by yeasts or via petrochemical processes such as ethylene hydration. Historically it was used as a general anesthetic, and has modern medical applications as an antiseptic, disinfectant, solvent for some medications, and antidote for methanol poisoning and ethylene glycol poisoning. It is used as a chemical solvent and in the Chemical synthesis, synthesis of orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
