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Ebonite
Ebonite is a brand name for a material generically known as hard rubber, and is obtained via vulcanizing natural rubber for prolonged periods. Ebonite may contain from 25% to 80% sulfur and linseed oil. Its name comes from its intended use as an artificial substitute for ebony wood. The material has also been called ''vulcanite'', although that name formally refers to the mineral vulcanite. Charles Goodyear's brother Nelson Goodyear experimented with the chemistry of ebonite composites. In 1851 he used zinc oxide as a filler. Hugh Silver was responsible for giving it its name. Properties The sulfur percentage and the applied temperatures and duration of vulcanizing are the main variables that determine the technical properties of the hard rubber polysulfide elastomer. The occurring reaction is basically addition of sulfur at the double bonds, forming intramolecular ring structures, so a large portion of the sulfur is highly cross-linked in the form of intramolecular additio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Rubber
Rubber, also called India rubber, latex, Amazonian rubber, ''caucho'', or ''caoutchouc'', as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Thailand, Malaysia, and Indonesia are three of the leading rubber producers. Types of polyisoprene that are used as natural rubbers are classified as elastomers. Currently, rubber is harvested mainly in the form of the latex from the rubber tree (''Hevea brasiliensis'') or others. The latex is a sticky, milky and white colloid drawn off by making incisions in the bark and collecting the fluid in vessels in a process called "tapping". The latex then is refined into the rubber that is ready for commercial processing. In major areas, latex is allowed to coagulate in the collection cup. The coagulated lumps are collected and processed into dry forms for sale. Natural rubber is used extensively in many applications and products, either alone or in combination wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tobacco Pipe
A tobacco pipe, often called simply a pipe, is a device specifically made to smoke tobacco. It comprises a chamber (the bowl) for the tobacco from which a thin hollow stem (shank) emerges, ending in a mouthpiece. Pipes can range from very simple machine-made briar models to highly prized hand-made artisanal implements made by renowned pipemakers, which are often very expensive collector's items. Pipe smoking is the oldest known traditional form of tobacco smoking. History Some cultures of the indigenous peoples of the Americas smoke tobacco in ceremonial pipes, and have done so since long before the arrival of Europeans. For instance the Lakota people use a ceremonial pipe called čhaŋnúŋpa. Other cultures of the indigenous peoples of the Americas smoke tobacco socially. The tobacco plant is native to South America but spread into North America long before Europeans arrived. Tobacco was introduced to Europe from the Americas in the 16th century and spread around the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ebony
Ebony is a dense black/brown hardwood, coming from several species in the genus '' Diospyros'', which also contains the persimmons. Unlike most woods, ebony is dense enough to sink in water. It is finely textured and has a mirror finish when polished, making it valuable as an ornamental wood. The word ''ebony'' comes from the Ancient Egyptian ', through the Ancient Greek ('), into Latin and Middle English. Species Species of ebony include ''Diospyros ebenum'' (Ceylon ebony), native to southern India and Sri Lanka; '' D. crassiflora'' (Gabon ebony), native to western Africa; and '' D. celebica'' (Sulawesi ebony), native to Indonesia and prized for its luxuriant, multi-colored wood grain. Mauritius ebony, '' D. tessellaria'', was largely exploited by the Dutch in the 17th century. Some species in the genus yield an ebony with similar physical properties, but striped rather than the even black of ''D. ebenum''. Uses Ebony has a long history of use, and carved pieces hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clarinet
The clarinet is a musical instrument in the woodwind family. The instrument has a nearly cylindrical bore and a flared bell, and uses a single reed to produce sound. Clarinets comprise a family of instruments of differing sizes and pitches. The clarinet family is the largest such woodwind family, with more than a dozen types, ranging from the BB♭ contrabass to the E♭ soprano. The most common clarinet is the B soprano clarinet. German instrument maker Johann Christoph Denner is generally credited with inventing the clarinet sometime after 1698 by adding a register key to the chalumeau, an earlier single-reed instrument. Over time, additional keywork and the development of airtight pads were added to improve the tone and playability. Today the clarinet is used in classical music, military bands, klezmer, jazz, and other styles. It is a standard fixture of the orchestra and concert band. Etymology The word ''clarinet'' may have entered the English language vi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fountain Pen
A fountain pen is a writing instrument which uses a metal nib to apply a water-based ink to paper. It is distinguished from earlier dip pens by using an internal reservoir to hold ink, eliminating the need to repeatedly dip the pen in an inkwell during use. The pen draws ink from the reservoir through a feed to the nib and deposits the ink on paper via a combination of gravity and capillary action. Filling the reservoir with ink may be achieved manually, via the use of an eyedropper or syringe, or via an internal filling mechanism which creates suction (for example, through a piston mechanism) or a vacuum to transfer ink directly through the nib into the reservoir. Some pens employ removable reservoirs in the form of pre-filled ink cartridges. History Early prototypes of reservoir pens According to Qadi al-Nu'man al-Tamimi (d. 974) in his ''Kitab al-Majalis wa 'l-musayarat'', the Fatimid caliph Al-Mu'izz li-Din Allah in Arab Egypt demanded a pen that would not stain his ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polypropylene
Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer propylene. Polypropylene belongs to the group of polyolefins and is partially crystalline and non-polar. Its properties are similar to polyethylene, but it is slightly harder and more heat-resistant. It is a white, mechanically rugged material and has a high chemical resistance. Bio-PP is the bio-based counterpart of polypropylene (PP). Polypropylene is the second-most widely produced commodity plastic (after polyethylene). In 2019, the global market for polypropylene was worth $126.03 billion. Revenues are expected to exceed US$145 billion by 2019. The sales of this material are forecast to grow at a rate of 5.8% per year until 2021. History Phillips Petroleum chemists J. Paul Hogan and Robert Banks first demonstrated the polymerization of propylene in 1951. The stereoselective polymerizat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caster
A caster (or castor) is an undriven wheel that is designed to be attached to the bottom of a larger object (the "vehicle") to enable that object to be moved. Casters are used in numerous applications, including shopping carts, office chairs, toy wagons, hospital beds, and material handling Material handling involves short-distance movement within the confines of a building or between a building and a transportation vehicle. It uses a wide range of manual, semi-automated, and automated equipment and includes consideration of the pro ... equipment. High capacity, heavy duty casters are used in many industrial applications, such as platform trucks, carts, assemblies, and tow lines in plants. Types Casters may be fixed to roll along a straight line path, or mounted on a pivot or pintle such that the wheel will automatically align itself to the direction of travel. Rigid casters A basic, rigid caster consists of a wheel mounted to a stationary fork. The orientation of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mouthpiece (woodwind)
The mouthpiece of a woodwind instrument is that part of the instrument which is placed partly in the player's mouth. Single-reed instruments, capped double-reed instruments, and fipple flutes have mouthpieces while exposed double-reed instruments (apart from those using pirouettes) and open flutes do not. The characteristics of a mouthpiece and reed can play a significant role on the sound of the instrument. Single-reed instruments On single-reed instruments, such as the clarinet and saxophone, the mouthpiece is that part to which the reed is attached. Its function is to provide an opening through which air enters the instrument and one end of an air chamber to be set into vibration by the interaction between the air stream and the reed. Single-reed mouthpieces are basically wedge shaped, with the reed placed against the surface closest to the player's lower lip (the ''table''). The player's breath causes the reed to vibrate. The reed beats against the mouthpiece, and in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saxophone
The saxophone (often referred to colloquially as the sax) is a type of Single-reed instrument, single-reed woodwind instrument with a conical body, usually made of brass. As with all single-reed instruments, sound is produced when a reed (mouthpiece), reed on a Mouthpiece (woodwind), mouthpiece vibrates to produce a sound wave inside the instrument's body. The Pitch (music), pitch is controlled by opening and closing holes in the body to change the effective length of the tube. The holes are closed by leather pads attached to keys operated by the player. Saxophones are made in various sizes and are almost always treated as transposing instruments. Saxophone players are called ''wikt:saxophonist, saxophonists''. The saxophone is used in a wide range of musical styles including classical music (such as concert bands, chamber music, List of concert works for saxophone, solo repertoire, and occasionally orchestras), military bands, marching bands, jazz (such as big bands and jazz comb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hockey Puck
A hockey puck is either an open or closed disk used in a variety of sports and games. There are designs made for use on an ice surface, such as in ice hockey, and others for the different variants of floor hockey which includes the wheeled skate variant of inline hockey ( roller hockey). They are all designed to serve the same function a ball does in ball games. A closed disk hockey puck having the shape of a short cylinder made of vulcanized rubber is used in the sport of ice hockey. The closed disk has also been referred to as a "flat ball." Hockey pucks are designed for use on either an ice surface, dry floor, or underwater, though open disk designs have only been used on floors. Open disk hockey pucks have a hole, forming the shape of a toroid, for use in a particular style of floor hockey. They should not be confused with ringette rings, which are toruses, for use in the sport of ringette. This article deals chiefly with the sport and game pucks which are closed d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poly(methyl Methacrylate)
Poly(methyl methacrylate) (PMMA) belongs to a group of materials called engineering plastics. It is a transparent thermoplastic. PMMA is also known as acrylic, acrylic glass, as well as by the trade names and brands Crylux, Plexiglas, Acrylite, Astariglas, Lucite, Perclax, and Perspex, among several others ( see below). This plastic is often used in sheet form as a lightweight or shatter-resistant alternative to glass. It can also be used as a casting resin, in inks and coatings, and for many other purposes. Although not a type of familiar silica-based glass, the substance, like many thermoplastics, is often technically classified as a type of glass, in that it is a non-crystalline vitreous substance—hence its occasional historic designation as ''acrylic glass''. Chemically, it is the synthetic polymer of methyl methacrylate. It was developed in 1928 in several different laboratories by many chemists, such as William Chalmers, Otto Röhm, and Walter Bauer, and first brough ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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