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HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

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Influenzavirus C
Influenza virus C is a genus in the virus family Orthomyxoviridae, which includes the viruses that cause influenza. The species in this genus is called Influenza C virus. Influenza C viruses are known to infect humans and pigs. Flu due to the Type C species is rare compared to Types A or B, but can be severe and can cause local epidemics. Type C has 7 RNA segments and encodes 9 proteins, while Types A and B have 8 RNA segments and encode at least 10 proteins.
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  • 01 Dec 2022
Topic Review
Ring Expansion and Ring Contraction
Ring expansion and ring contraction reactions in the course of organic synthesis refer to a set of reactions which can lead to the expansion or contraction of an existing ring. This often makes it possible to access structures that would be difficult if not impossible to synthesise with single cyclization reactions. Ring expansions are valuable because they allow access to larger systems that are difficult to synthesize through a single cyclization due to the slow rate of formation. Ring contractions are useful for making smaller, more strained rings from larger rings. Expansions are classified by the mechanism of expansion and the atom(s) added; contractions are characterized simply by the reactive intermediate which performs the contraction.
  • 4.2K
  • 01 Dec 2022
Topic Review
Texture
In physical chemistry and materials science, texture is the distribution of crystallographic orientations of a polycrystalline sample (it is also part of the geological fabric). A sample in which these orientations are fully random is said to have no distinct texture. If the crystallographic orientations are not random, but have some preferred orientation, then the sample has a weak, moderate or strong texture. The degree is dependent on the percentage of crystals having the preferred orientation. Texture is seen in almost all engineered materials, and can have a great influence on materials properties. The texture forms in materials during thermo-mechanical processes, for example during production processes e.g. rolling. Consequently, the rolling process is often followed by a heat treatment to reduce the amount of unwanted texture. Controlling the production process in combination with the characterization of texture and the material's microstructure help to determine the materials properties, i.e. the processing-microstructure-texture-property relationship. Also, geologic rocks show texture due to their thermo-mechanic history of formation processes. One extreme case is a complete lack of texture: a solid with perfectly random crystallite orientation will have isotropic properties at length scales sufficiently larger than the size of the crystallites. The opposite extreme is a perfect single crystal, which likely has anisotropic properties by geometric necessity.
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  • 01 Dec 2022
Topic Review
Well-Defined
In mathematics, an expression is called well-defined or unambiguous if its definition assigns it a unique interpretation or value. Otherwise, the expression is said to be not well-defined, ill-defined or ambiguous. A function is well-defined if it gives the same result when the representation of the input is changed without changing the value of the input. For instance, if f takes real numbers as input, and if f(0.5) does not equal f(1/2) then f is not well-defined (and thus not a function). The term well-defined can also be used to indicate that a logical expression is unambiguous or uncontradictory. A function that is not well-defined is not the same as a function that is undefined. For example, if f(x) = 1/x, then the fact that f(0) is undefined does not mean that the f is not well-defined — but that 0 is simply not in the domain of f.
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  • 01 Dec 2022
Topic Review
Savoia-Marchetti SM.81
The Savoia-Marchetti SM.81 Pipistrello (Italian: bat) was the first three-engine bomber/transport aircraft serving in the Italian Regia Aeronautica. When it appeared in 1935, it represented a real step ahead in Italian military aviation: it was fast, well armed and had a long range. It proved effective during the war with Ethiopia and the Spanish Civil War. Despite being too slow to remain competitive as a bomber in the later years of World War II, it was one of the most flexible, reliable and important aircraft of the Regia Aeronautica from 1935 to 1944, and adapted to second-line duties in a wide range of tasks.
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  • 01 Dec 2022
Topic Review
Shopping Hours
Customs and regulations for shopping hours for sunday (times that shops are open) vary from countries to cities.
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  • 01 Dec 2022
Biography
William V. Houston
William Vermillion Houston (January 19, 1900 – August 22, 1968) was an United States physicist who made contributions to spectroscopy, quantum mechanics, and solid-state physics as well as being a teacher and administrator. He became the second president of Rice University in 1946. His family name is pronounced HOW-stun, in contrast to the pronunciation of the city of Houston in which he live
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  • 01 Dec 2022
Topic Review
IKCO EF Engines
IKCO EF engines are a family of four-cylinder engines. The EF7 series are designed jointly by Iran Khodro Powertrain Company (IPCO) and F.E.V GmbH of Germany. The other models will be designed by IPCO itself. IPCO is the powertrain designing & producing company of Iranian car manufacturer Iran Khodro (IKCO). IKCO aims to supply 800,000 powertrains by 2010. The first phase of IKCO EF Engines project (EF7 Dual-Fuel) investments were about 80 million US$. EF4 & EF7 engines use CNG as their main fuel and they can also use gasoline. EFD is the first engine of the EF family that is single-fuel. It uses high-quality diesel (Euro 4 Quality or better) as fuel. EF engines share most of their parts between them. It was IKCO's aim to reduce costs and provide ease of supplying the parts in the future for after-sales services. The EF family dual-fuel and petrol-fuel engines have achieved the Euro IV emission standard and are able to achieve Euro V emission standard with some minor changes but EFD will be the first engine of the family which comes with the Euro IV emission standard as its first release, and is able to achieve the Euro VI emission standard with some changes. The most important suppliers for EF engines are INA for sensitive VVT parts and some other mechanical parts, MAHLE which supplies some important parts of the engine family such as pistons, with Bosch supplying the ECU and electrically controlled pedal and lots of other important sensitive electronic parts. Almost all of the parts (except high-tech and sensitive parts) from worldwide well-known companies (as mentioned) are produced in Iran under license with the highest required quality for the engines. The Germany company Bosch had shown interest in assembling the Iranian engine under license. In 2008 IKCO has announced that EF7 is among the three best CNG-based engines of the world in designing.
  • 12.8K
  • 01 Dec 2022
Topic Review
Physical Law
A physical law or a law of physics is a statement "inferred from particular facts, applicable to a defined group or class of phenomena, and expressible by the statement that a particular phenomenon always occurs if certain conditions be present." Physical laws are typically conclusions based on repeated scientific experiments and observations over many years and which have become accepted universally within the scientific community. The production of a summary description of our environment in the form of such laws is a fundamental aim of science. These terms are not used the same way by all authors. The distinction between natural law in the political-legal sense and law of nature or physical law in the scientific sense is a modern one, both concepts being equally derived from physis, the Greek word (translated into Latin as natura) for nature.
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  • 01 Dec 2022
Topic Review
IAM RoadSmart
IAM RoadSmart formerly called the Institute of Advanced Motorists (IAM) is a charity based in the United Kingdom and serving nine countries, whose objective is to improve car driving and motorcycle riding standards, and so enhance road safety, by using the British police's system of car and motorcycle control commonly known as "the System". The System was devised in 1937 by racing driver Mark Everard Pepys, 6th Earl of Cottenham, to reduce accidents in police pursuits. People who have passed an IAM test have substantially fewer accidents and typically report getting more pleasure from driving too. Research has shown that IAM training increases a wide range of driving skills, including speed, safe distances, gear changing and cornering. The IAM was formed in 1956 and has over 82,000 members, all of whom have taken and passed an advanced test in a car, commercial vehicle or on a motorcycle. In 2006, the charity took over the work of the AA Motoring Trust, which had been established in 2002 by The Automobile Association. The charity brought its different activities and programmes together under one umbrella called IAM RoadSmart in 2016.
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  • 01 Dec 2022
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