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Thumbtack
A drawing pin (in British English) or thumb tack (in North American English) is a short nail or pin used to fasten items to a wall or board for display and intended to be inserted by hand, usually using the thumb. A variety of names is used to refer to different designs intended for various purposes. Thumb tacks made of brass, tin or iron may be referred to as brass tacks, brass pins, tin tacks or iron tacks, respectively. These terms are particularly used in the idiomatic expression ''to come'' (or ''get'') ''down to brass'' (or otherwise) ''tacks'', meaning to consider basic facts of a situation. History The drawing pin was invented in name and first mass-produced in what is now the United States in the mid/late 1750s. It was first mentioned in the Oxford English Dictionary in 1759. It was said that the use of the newly invented drawing pin to attach notices to school house doors was making significant contribution to the whittling away of their gothic doors. Modern draw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lychen
Lychen (), also known as ''Flößerstadt'' (raftsman city), is a town in the Uckermark district, in Brandenburg, Germany. It is situated southeast of Neustrelitz, and east of Fürstenberg/Havel. This is the town where the thumbtack was created. History Historically, timber rafting was one of the most important sectors of the economy. The timber was built into rafts and used for building projects, and was also used to transport other goods. Lychen has a timber rafting museum, and tourists can travel by raft on the lake. Flat-headed thumbtacks were invented in Lychen in 1903 by Johann Kirsten. His invention is celebrated in a memorial. At the beginning of the 20th century there were a number of small factories here manufacturing thumbtacks. The Hohenlychen Sanatorium used by the Schutzstaffel during World War II, is located in the town. Demography File:Bevölkerungsentwicklung Lychen.pdf, Development of population since 1875 within the current Boundaries (Blue Line: Popul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fasteners
A fastener (US English) or fastening (UK English) is a hardware device that mechanically joins or affixes two or more objects together. In general, fasteners are used to create non-permanent joints; that is, joints that can be removed or dismantled without damaging the joining components. Welding is an example of creating permanent joints. Steel fasteners are usually made of stainless steel, carbon steel, or alloy steel. Other alternative methods of joining materials include: crimping, welding, soldering, brazing, taping, gluing, cement, or the use of other adhesives. Force may also be used, such as with magnets, vacuum (like suction cups), or even friction (like sticky pads). Some types of woodworking joints make use of separate internal reinforcements, such as dowels or biscuits, which in a sense can be considered fasteners within the scope of the joint system, although on their own they are not general purpose fasteners. Furniture supplied in flat-pack form often uses cam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plastic
Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptability, plus a wide range of other properties, such as being lightweight, durable, flexible, and inexpensive to produce, has led to its widespread use. Plastics typically are made through human industrial systems. Most modern plastics are derived from fossil fuel-based chemicals like natural gas or petroleum; however, recent industrial methods use variants made from renewable materials, such as corn or cotton derivatives. 9.2 billion tonnes of plastic are estimated to have been made between 1950 and 2017. More than half this plastic has been produced since 2004. In 2020, 400 million tonnes of plastic were produced. If global trends on plastic demand continue, it is estimated that by 2050 annual global plastic production will reach over 1, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Products Introduced In 1900
Product may refer to: Business * Product (business), an item that serves as a solution to a specific consumer problem. * Product (project management), a deliverable or set of deliverables that contribute to a business solution Mathematics * Product (mathematics) Algebra * Direct product Set theory * Cartesian product of sets Group theory * Direct product of groups * Semidirect product * Product of group subsets * Wreath product * Free product * Zappa–Szép product (or knit product), a generalization of the direct and semidirect products Ring theory * Product of rings * Ideal operations, for product of ideals Linear algebra * Scalar multiplication * Matrix multiplication * Inner product, on an inner product space * Exterior product or wedge product * Multiplication of vectors: ** Dot product ** Cross product ** Seven-dimensional cross product ** Triple product, in vector calculus * Tensor product Topology * Product topology Algebraic topology * Cap product * Cup product * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Lancet
''The Lancet'' is a weekly peer-reviewed general medical journal and one of the oldest of its kind. It is also the world's highest-impact academic journal. It was founded in England in 1823. The journal publishes original research articles, review articles ("seminars" and "reviews"), editorials, book reviews, correspondence, as well as news features and case reports. ''The Lancet'' has been owned by Elsevier since 1991, and its editor-in-chief since 1995 has been Richard Horton. The journal has editorial offices in London, New York City, and Beijing. History ''The Lancet'' was founded in 1823 by Thomas Wakley, an English surgeon who named it after the surgical instrument called a lancet (scalpel). Members of the Wakley family retained editorship of the journal until 1908. In 1921, ''The Lancet'' was acquired by Hodder & Stoughton. Elsevier acquired ''The Lancet'' from Hodder & Stoughton in 1991. Impact According to the ''Journal Citation Reports'', the journal has a 202 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FEMA - 44675 - Logistics Maps Locations Of Disaster Recovery Centers
The Federal Emergency Management Agency (FEMA) is an agency of the United States Department of Homeland Security (DHS), initially created under President Jimmy Carter by Presidential Reorganization Plan No. 3 of 1978 and implemented by two Executive Orders on April 1, 1979. The agency's primary purpose is to coordinate the response to a disaster that has occurred in the United States and that overwhelms the resources of local and state authorities. The governor of the state in which the disaster occurs must declare a state of emergency and formally request from the President that FEMA and the federal government respond to the disaster. The only exception to the state's gubernatorial declaration requirement occurs when an emergency or disaster takes place on federal property or to a federal asset—for example, the 1995 bombing of the Alfred P. Murrah Federal Building in Oklahoma City, Oklahoma, or the Space Shuttle ''Columbia'' in the 2003 return-flight disaster. While on-the- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star (polygon)
In geometry, a star polygon is a type of non-convex polygon. Regular star polygons have been studied in depth; while star polygons in general appear not to have been formally defined, certain notable ones can arise through truncation operations on regular simple and star polygons. Branko Grünbaum identified two primary definitions used by Johannes Kepler, one being the regular star polygons with intersecting edges that don't generate new vertices, and the second being simple isotoxal concave polygons. The first usage is included in polygrams which includes polygons like the pentagram but also compound figures like the hexagram. One definition of a ''star polygon'', used in turtle graphics, is a polygon having 2 or more turns (turning number and density), like in spirolaterals.Abelson, Harold, diSessa, Andera, 1980, ''Turtle Geometry'', MIT Press, p.24 Etymology Star polygon names combine a numeral prefix, such as ''penta-'', with the Greek suffix '' -gram'' (in this cas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heart (symbol)
The heart symbol is an ideograph used to express the idea of the "heart" in its metaphorical or symbolic sense. Represented by an anatomically inaccurate shape, the heart symbol is often used to represent the center of emotion, including affection and love, especially romantic love. It is sometimes accompanied or superseded by the "wounded heart" symbol, depicted as a heart symbol pierced with an arrow or as a heart symbol "broken" into two or more pieces, indicating lovesickness. History Similar shapes from antiquity Peepal leaves were used in artistic depictions of the Indus Valley civilisation: a heart-shaped pendant originating from there has been discovered and is now exhibited in the Delhi national museum. In the 5th–6th century BC, the heart shape was used to represent the heart-shaped fruit of the plant silphium, a plant possibly used as a contraceptive and an aphrodisiac. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steel
Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant typically need an additional 11% chromium. Because of its high tensile strength and low cost, steel is used in buildings, infrastructure, tools, ships, trains, cars, machines, electrical appliances, weapons, and rockets. Iron is the base metal of steel. Depending on the temperature, it can take two crystalline forms (allotropic forms): body-centred cubic and face-centred cubic. The interaction of the allotropes of iron with the alloying elements, primarily carbon, gives steel and cast iron their range of unique properties. In pure iron, the crystal structure has relatively little resistance to the iron atoms slipping past one another, and so pure iron is quite ductile, or soft and easily formed. In steel, small amounts of carbon, other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wood
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin that resists compression. Wood is sometimes defined as only the secondary xylem in the stems of trees, or it is defined more broadly to include the same type of tissue elsewhere such as in the roots of trees or shrubs. In a living tree it performs a support function, enabling woody plants to grow large or to stand up by themselves. It also conveys water and nutrients between the leaves, other growing tissues, and the roots. Wood may also refer to other plant materials with comparable properties, and to material engineered from wood, or woodchips or fiber. Wood has been used for thousands of years for fuel, as a construction material, for making tools and weapons, furniture and paper. More recently it emerged as a feedstock for the productio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metal
A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typically ductile (can be drawn into wires) and malleable (they can be hammered into thin sheets). These properties are the result of the ''metallic bond'' between the atoms or molecules of the metal. A metal may be a chemical element such as iron; an alloy such as stainless steel; or a molecular compound such as polymeric sulfur nitride. In physics, a metal is generally regarded as any substance capable of conducting electricity at a temperature of absolute zero. Many elements and compounds that are not normally classified as metals become metallic under high pressures. For example, the nonmetal iodine gradually becomes a metal at a pressure of between 40 and 170 thousand times atmospheric pressure. Equally, some materials regarded as metals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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