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Ebonite
Ebonite is a brand name for a material generically known as hard rubber or vulcanite, 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 intramolecul ... [...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. 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 Hevea brasiliensis, Pará 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". Manufacturers refine this latex into the rubber that is ready for commercial processing. Natural rubber is used extensively in many applications and products, either alone or in combination with other materials. In most of its useful forms, it has a large stretch ratio and high resilience and also is buoyant and water-proof. Industrial demand for rubber-like materials began to out ... [...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 (smoking), 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. 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, Lakota people use a ceremonial pipe called Chanunpa, 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 world rapidly. As tobacco was no ... [...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 includes the persimmon tree. A few ''Diospyros'' species, such as macassar and mun ebony, are dense enough to sink in water. Ebony is finely textured and has a mirror finish when polished, making it valuable as an ornamental wood. It is often cited as one of the most expensive woods in the world. Etymology 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; '' D. humilis'' (Queensland ebony), native to Queensland, the Northern Territory, New Guinea and Timor; 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clarinet
The clarinet is a Single-reed instrument, single-reed musical instrument in the woodwind family, with a nearly cylindrical bore (wind instruments), bore and a flared bell. Clarinets comprise a Family (musical instruments), family of instruments of differing sizes and pitches. The clarinet family is the largest woodwind family, ranging from the contrabass clarinet, BB♭ contrabass to the A-flat clarinet, A♭ piccolo. The B soprano clarinet is the most common type, and is the instrument usually indicated by the word "clarinet". German instrument maker Johann Christoph Denner is generally credited with inventing the clarinet sometime around 1700 by adding a register key to the chalumeau, an earlier single-reed instrument. Over time, additional keywork and airtight pads were added to improve the tone and playability. Today the clarinet is a standard fixture of the orchestra and concert band and is used in classical music, military bands, klezmer, jazz, and other styles. Etymol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fountain Pen
A fountain pen is a writing instrument that uses a metal nib (pen), nib to apply Fountain pen ink, water-based ink, or special pigment ink—suitable for fountain pens—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 that 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 () in his ''Kitab al-Majalis wa 'l-musayarat'', the Fatimid caliph Al-Mu'izz ... [...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 Propene, propylene. Polypropylene belongs to the group of polyolefins and is Crystallization of polymers#Degree of crystallinity, partially crystalline and Chemical polarity#Nonpolar molecules, 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. Polypropylene is the second-most widely produced Commodity plastics, commodity plastic (after polyethylene). History Phillips Petroleum chemists J. Paul Hogan and Robert Banks (chemist), Robert Banks first demonstrated the polymerization of propylene in 1951. The stereoselective polymerization to the isotactic was discovered by Giulio Natta and Karl Rehn in March 1954. This pioneering discovery led to large-scale commercial producti ... [...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 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 fork, which is fixed relative to the vehicle, is determined when the caster is mounted to the vehicle. An example of this is the wheels found at the rear of a shopping cart in North America. Rigid casters tend to restrict vehicle motion so that the vehicle ... [...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. List of woodwind instruments#Single-reed, Single-reed instruments, List of woodwind instruments#Capped, capped double-reed instruments, and List of woodwind instruments#Closed (fipple), fipple flutes have mouthpieces while List of woodwind instruments#Exposed, exposed double-reed instruments (apart from those using #Pirouettes, pirouettes) and List of woodwind instruments#Open, 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 bore (wind instruments), air chamber to be set into vibration by the interaction between the air stream and the reed. Single-ree ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saxophone
The saxophone (often referred to colloquially as the sax) is a type of single-reed woodwind instrument with a conical body, usually made of brass. As with all single-reed instruments, sound is produced when a reed on a mouthpiece vibrates to produce a sound wave inside the instrument's body. The 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. A person who plays the saxophone is called a ''saxophonist'' or ''saxist''. The saxophone is used in a wide range of musical styles including classical music (such as concert bands, chamber music, solo repertoire, and occasionally orchestras), military bands, marching bands, jazz (such as big bands and jazz combos), and contemporary music. The saxophone is also used as a solo and melody instrument or as a mem ... [...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. 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 disks. Etymology The origin of the word ''puck'' is vague. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poly(methyl Methacrylate)
Poly(methyl methacrylate) (PMMA) is a synthetic polymer derived from methyl methacrylate. It is a transparent thermoplastic, used as an engineering plastic. PMMA is also known as acrylic, acrylic glass, as well as by the trade names and brands Crylux, Walcast, Hesalite, Plexiglas, Acrylite, 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. It 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''. History The first acrylic acid was created in 1843. Methacrylic acid, derived from acrylic acid, was formulated in 1865. The reaction between methacrylic acid and methanol results in the ester methyl methacrylate. It was developed in 1928 in several different la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
