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Glue Jet
Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advantages over other binding techniques such as sewing, mechanical fastenings, and welding. These include the ability to bind different materials together, the more efficient distribution of stress across a joint, the cost-effectiveness of an easily mechanized process, and greater flexibility in design. Disadvantages of adhesive use include decreased stability at high temperatures, relative weakness in bonding large objects with a small bonding surface area, and greater difficulty in separating objects during testing. Adhesives are typically organized by the method of adhesion followed by ''reactive'' or ''non-reactive'', a term which refers to whether the adhesive chemically reacts in order to harden. Alternatively, they can be organized either ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrolean Iceman
Tyrolean may refer to: * Anything from Tyrol (state) Tyrol ( ; ; ) is an Austrian Provinces of Austria, federal state. It comprises the Austrian part of the historical County of Tyrol, Princely County of Tyrol. It is a constituent part of the present-day Euroregion Tyrol–South Tyrol–Trenti ... (Austria), South Tyrol (Italy) or the historical County of Tyrol or region of Tyrol * Tyrolean Zugspitze Cable Car * Tyrolean Airways * Tyrolean hat * Tyrolean traverse, mountaineering manoeuvre * Tyrolean Hound * A type of cement render, applied by a hand-operated machine {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tendon
A tendon or sinew is a tough band of fibrous connective tissue, dense fibrous connective tissue that connects skeletal muscle, muscle to bone. It sends the mechanical forces of muscle contraction to the skeletal system, while withstanding tension (physics), tension. Tendons, like ligaments, are made of collagen. The difference is that ligaments connect bone to bone, while tendons connect muscle to bone. There are about 4,000 tendons in the adult human body. Structure A tendon is made of dense regular connective tissue, whose main cellular components are special fibroblasts called tendon cells (tenocytes). Tendon cells synthesize the tendon's extracellular matrix, which abounds with densely-packed collagen fibers. The collagen fibers run parallel to each other and are grouped into fascicles. Each fascicle is bound by an endotendineum, which is a delicate loose connective tissue containing thin collagen fibrils and elastic fibers. A set of fascicles is bound by an epitenon, whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horn (anatomy)
A horn is a permanent pointed projection on the head of various animals that consists of a covering of keratin and other proteins surrounding a core of live bone. Horns are distinct from antlers, which are not permanent. In mammals, true horns are found mainly among the ruminant artiodactyls, in the families Antilocapridae ( pronghorn) and Bovidae ( cattle, goats, antelope etc.). Cattle horns arise from subcutaneous connective tissue (under the scalp) and later fuse to the underlying frontal bone. One pair of horns is usual; however, two or more pairs occur in a few wild species and in some domesticated breeds of sheep. Polycerate (multi-horned) sheep breeds include the Hebridean, Icelandic, Jacob, Manx Loaghtan, and the Navajo-Churro. Horns usually have a curved or spiral shape, often with ridges or fluting. In many species, only males have horns. Horns start to grow soon after birth and continue to grow throughout the life of the animal (except in pronghorns, whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mongols
Mongols are an East Asian ethnic group native to Mongolia, China ( Inner Mongolia and other 11 autonomous territories), as well as the republics of Buryatia and Kalmykia in Russia. The Mongols are the principal member of the large family of Mongolic peoples. The Oirats and the Buryats are classified either as distinct ethno-linguistic groups or as subgroups of Mongols. The Mongols are bound together by a common heritage and ethnic identity, descending from the Proto-Mongols. Their indigenous dialects are collectively known as the Mongolian language. The contiguous geographical area in which the Mongols primarily live is referred to as the Mongol heartland, especially in discussions of the Mongols' history under the Mongol Empire. Definition Broadly defined, the term includes the Mongols proper (also known as the Khalkha Mongols), Buryats, Oirats, the Kalmyks and the Southern Mongols. The latter comprises the Abaga Mongols, Abaganar, Aohans, Arkhorchin, Asud, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pozzolana
Pozzolana or pozzuolana ( , ), also known as pozzolanic ash (), is a natural siliceous or siliceous- aluminous material which reacts with calcium hydroxide in the presence of water at room temperature (cf. pozzolanic reaction). In this reaction insoluble calcium silicate hydrate and calcium aluminate hydrate compounds are formed possessing cementitious properties. The designation pozzolana is derived from one of the primary deposits of volcanic ash used by the Romans in Italy, at Pozzuoli. The modern definition of pozzolana encompasses any volcanic material ( pumice or volcanic ash), predominantly composed of fine volcanic glass, that is used as a pozzolan. Note the difference with the term pozzolan, which exerts no bearing on the specific origin of the material, as opposed to pozzolana, which can only be used for pozzolans of volcanic origin, primarily composed of volcanic glass. Historical use Pozzolanas such as Santorin earth were used in the Eastern Mediterranean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slaked Lime
Calcium hydroxide (traditionally called slaked lime) is an inorganic compound with the chemical formula Ca( OH)2. It is a colorless crystal or white powder and is produced when quicklime ( calcium oxide) is mixed with water. Annually, approximately 125 million tons of calcium hydroxide are produced worldwide. Calcium hydroxide has many names including hydrated lime, caustic lime, builders' lime, slaked lime, cal, and pickling lime. Calcium hydroxide is used in many applications, including food preparation, where it has been identified as E number E526. Limewater, also called milk of lime, is the common name for a saturated solution of calcium hydroxide. Solubility Calcium hydroxide is moderately soluble in water, as seen for many dihydroxides. Its solubility increases from 0.66 g/L at 100 °C to 1.89 g/L at 0 °C. Its solubility product ''K''sp of 5.02 at 25 °C, its dissociation in water is large enough that its solutions are basic according to the following ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marquetry
Marquetry (also spelled as marqueterie; from the French ''marqueter'', to variegate) is the art and craft of applying pieces of wood veneer, veneer to a structure to form decorative patterns or designs. The technique may be applied to case furniture or even seat furniture, to decorative small objects with smooth, veneerable surfaces or to freestanding pictorial panels appreciated in their own right. Marquetry differs from the more ancient craft of inlay, or intarsia, in which a solid body of one material is cut out to receive sections of another to form the surface pattern. The word derives from a Middle French word meaning "inlaid work". Materials The veneers used are primarily woods, but may include bone, ivory, turtle-shell (conventionally called "Tortoiseshell material, tortoiseshell"), mother-of-pearl, pewter, brass or fine metals. Marquetry using colored Straw marquetry, straw was a specialty of some European spa resorts from the end of the 18th century. Many exotic wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wood Veneer
Veneer refers to thin slices of wood and sometimes bark that typically are glued onto core panels (typically, wood, particle board or medium-density fiberboard) to produce flat panels such as doors, tops and panels for cabinets, parquet floors and parts of furniture. They are also used in marquetry. Unlike laminates, no two veneer sheets look the same. Plywood consists of three or more layers of veneer. Normally, each is glued with its grain at right angles to adjacent layers for strength. Veneer beading is a thin layer of decorative edging placed around objects, such as jewelry boxes. Veneer is also used to replace decorative papers in wood veneer high pressure laminate. Background Veneering dates back to at least the ancient Egyptians who used expensive and rare wood veneers over cheaper timbers to produce their furniture and sarcophagi. During the Roman Empire, Romans also used veneered work in mass quantities. Production Veneer is obtained either by "peeling ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molten Beeswax
Melting, or fusion, is a physical process that results in the phase transition of a substance from a solid to a liquid. This occurs when the internal energy of the solid increases, typically by the application of heat or pressure, which increases the substance's temperature to the melting point. At the melting point, the ordering of ions or molecules in the solid breaks down to a less ordered state, and the solid melts to become a liquid. Substances in the molten state generally have reduced viscosity as the temperature increases. An exception to this principle is elemental sulfur, whose viscosity increases in the range of 130 °C to 190 °C due to polymerization. Some organic compounds melt through mesophases, states of partial order between solid and liquid. First order phase transition From a thermodynamics point of view, at the melting point the change in Gibbs free energy ''∆G'' of the substances is zero, but there are non-zero changes in the enthalpy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plaster Of Paris
Plaster is a building material used for the protective or decorative coating of walls and ceilings and for moulding and casting decorative elements. In English, "plaster" usually means a material used for the interiors of buildings, while "render" commonly refers to external applications. The term stucco refers to plasterwork that is worked in some way to produce relief decoration, rather than flat surfaces. The most common types of plaster mainly contain either gypsum, lime, or cement,Franz Wirsching "Calcium Sulfate" in Ullmann's Encyclopedia of Industrial Chemistry, 2012 Wiley-VCH, Weinheim. but all work in a similar way. The plaster is manufactured as a dry powder and is mixed with water to form a stiff but workable paste immediately before it is applied to the surface. The reaction with water liberates heat through crystallization and the hydrated plaster then hardens. Plaster can be relatively easily worked with metal tools and sandpaper and can be moulded, either ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Papyrus
Papyrus ( ) is a material similar to thick paper that was used in ancient times as a writing surface. It was made from the pith of the papyrus plant, ''Cyperus papyrus'', a wetland sedge. ''Papyrus'' (plural: ''papyri'' or ''papyruses'') can also refer to a document written on sheets of such material, joined side by side and rolled up into a scroll, an early form of a book. Papyrus was first known to have been used in Egypt (at least as far back as the First Dynasty of Egypt, First Dynasty), as the papyrus plant was once abundant across the Nile Delta. It was also used History of the Mediterranean, throughout the Mediterranean region. Apart from writing material, ancient Egyptians employed papyrus in the construction of other Artifact (archaeology), artifacts, such as reed boats, mats, rope, sandals, and baskets. History Papyrus was first manufactured in Egypt as far back as the third millennium BCE.H. Idris Bell and T.C. Skeat, 1935"Papyrus and its uses"(British Museum pam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
