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Polychlorinated Naphthalene
Polychlorinated naphthalene (PCN) are the products obtained upon treatment of naphthalene with chlorine. The generic chemical formula is C10 H8−(m+n) Cl(m+n). Commercial PCNs are mixtures of up to 75 components and byproducts.van de Plassche, E.; Schwegler, A. (2002)''Polychlorinated naphthalenes, Preliminary Risk Profile''Ministry of VROM/DGM, Netherlands The material is an oil or a waxy solid, depending on the degree of chlorination. PCNs were once used in insulating coatings for electrical wires, as well as other applications, but their use has been largely phased out. Chemical structure of PCN congeners There are 75 different PCN congeners. Production PCNs started to be produced for high-volume uses around 1910 in both Europe and the United States.Chlorinated naphthalenes , Chemical Assessment Rep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PCN Structure General
PCN or pcn may refer to: Arts and entertainment * Pennsylvania Cable Network, non-profit cable television network of Pennsylvania, US * ''Personal Computer News'', a defunct computer magazine * PCN (band), a Mexican metal band Organisations * Partido de Conciliación Nacional, former name of the National Coalition political party in El Salvador * Partidul Comuniştilor (Nepecerişti), the Communist Party in Romania Science and technology * Process control network, a communications network that transmits instructions and data between control and measurement units and SCADA equipment * Penicillin (PCN) * Pavement classification number, a code classifying types of surface at airports * Polychlorinated naphthalene, an organic pollutant * Potato cyst nematode, an agricultural pest * Program Composition Notation, a language for parallel programming * '' Polycycnis'' (Pcn), a genus of orchid * Personal communications network, mobile telephone system, Europe Other uses * Pecked curvi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloracne
Chloracne is an acne-like eruption of blackheads, cysts, and pustules associated with exposure to certain halogenated aromatic compounds, such as chlorinated dioxins and dibenzofurans. The lesions are most frequently found on the cheeks, behind the ears, in the armpits and groin region. The condition was first described in German industrial workers in 1897 by Siegfried Bettmann, and was initially believed to be caused by exposure to chlorine (hence the name "chloracne"). It was only in the mid-1950s that chloracne was associated with aromatic hydrocarbons. The substances that may cause chloracne are now collectively known as chloracnegens. Chloracne is particularly linked to toxic exposure to dioxins ( byproducts of many chemical processes, including the manufacture of herbicides such as Agent Orange)—so much so that it is considered a clinical sign of dioxin exposure. The severity and onset of chloracne may follow a typical asymptotic dose-response relationship curve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloroarenes
In organic chemistry, an aryl halide (also known as haloarene) is an aromatic compound in which one or more hydrogen atoms, directly bonded to an aromatic ring are replaced by a halide. The haloarene are different from haloalkanes because they exhibit many differences in methods of preparation and properties. The most important members are the aryl chlorides, but the class of compounds is so broad that there are many derivatives and applications. Preparation The two main preparatory routes to aryl halides are direct halogenation and via diazonium salts. Direct halogenation In the Friedel-Crafts halogenation, Lewis acids serve as catalysts. Many metal chlorides are used, examples include iron(III) chloride or aluminium chloride. The most important aryl halide, chlorobenzene is produced by this route. Monochlorination of benzene is always accompanied by formation of the dichlorobenzene derivatives. Arenes with electron donating groups react with halogens even in the absence of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-Chloronaphthalene
2-Chloronaphthalene is an organochlorine chemical compound, a chlorinated derivative of naphthalene. Its chemical formula is . The compound is an isomer for 1-chloronaphthalene. Synthesis 2-Chloronaphthalene is obtained directly by chlorination of naphthalene, with the formation of more highly substituted derivatives such as dichloro- and trichloronaphthalenes, in addition to the two monochlorinated isomeric compounds: 1-chloronaphthalene and 2-chloronaphthalene. Properties 2-Chloronaphthalene is a combustible, off-white odorless solid, which is practically insoluble in water. The compound may react with strong oxidizing agents. Applications 2-Chloronaphthalene can be used for the production of fullerenes. See also *1-Fluoronaphthalene *1-Bromonaphthalene 1-Bromonaphthalene is an organic compound with the formula C10H7Br. It is one of two isomeric bromonaphthalenes, the other being 2-bromonaphthalene. Under normal conditions, the substance is a colorless liquid. Synthesis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stockholm Convention On Persistent Organic Pollutants
Stockholm Convention on Persistent Organic Pollutants is an international environmental treaty, signed on 22 May 2001 in Stockholm and effective from 17 May 2004, that aims to eliminate or restrict the production and use of persistent organic pollutants (POPs). History In 1995, the Governing Council of the United Nations Environment Programme (UNEP) called for global action to be taken on POPs, which it defined as "chemical substances that persist in the environment, bio-accumulate through the food web, and pose a risk of causing adverse effects to human health and the environment". Following this, the Intergovernmental Forum on Chemical Safety (IFCS) and the International Programme on Chemical Safety (IPCS) prepared an assessment of the 12 worst offenders, known as the ''dirty dozen''. The INC met five times between June 1998 and December 2000 to elaborate the convention, and delegates adopted the Stockholm Convention on POPs at the Conference of the Plenipotentiaries co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Ireland
Northern Ireland ( ga, Tuaisceart Éireann ; sco, label= Ulster-Scots, Norlin Airlann) is a part of the United Kingdom, situated in the north-east of the island of Ireland, that is variously described as a country, province or region. Northern Ireland shares an open border to the south and west with the Republic of Ireland. In 2021, its population was 1,903,100, making up about 27% of Ireland's population and about 3% of the UK's population. The Northern Ireland Assembly (colloquially referred to as Stormont after its location), established by the Northern Ireland Act 1998, holds responsibility for a range of devolved policy matters, while other areas are reserved for the UK Government. Northern Ireland cooperates with the Republic of Ireland in several areas. Northern Ireland was created in May 1921, when Ireland was partitioned by the Government of Ireland Act 1920, creating a devolved government for the six northeastern counties. As was intended, Northern Ireland ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neoprene
Neoprene (also polychloroprene) is a family of synthetic rubbers that are produced by polymerization of chloroprene.Werner Obrecht, Jean-Pierre Lambert, Michael Happ, Christiane Oppenheimer-Stix, John Dunn and Ralf Krüger "Rubber, 4. Emulsion Rubbers" in Ullmann's Encyclopedia of Industrial Chemistry, 2012, Wiley-VCH, Weinheim. Neoprene exhibits good chemical stability and maintains flexibility over a wide temperature range. Neoprene is sold either as solid rubber or in latex form and is used in a wide variety of commercial applications, such as laptop sleeves, orthopaedic braces (wrist, knee, etc.), electrical insulation, liquid and sheet-applied elastomeric membranes or flashings, and automotive fan belts. Production Neoprene is produced by free-radical polymerization of chloroprene. In commercial production, this polymer is prepared by free radical emulsion polymerization. Polymerization is initiated using potassium persulfate. Bifunctional nucleophiles, metal oxides (e.g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxic Substances Control Act Of 1976
The Toxic Substances Control Act (TSCA) is a United States law, passed by the 94th United States Congress in 1976 and administered by the United States Environmental Protection Agency (EPA), that regulates chemicals not regulated by other U.S. federal statutes, including chemicals already in commerce and the introduction of new chemicals.Auer, Charles, Frank Kover, James Aidala, Marks Greenwood“Toxic Substances: A Half Century of Progress.”EPA Alumni Association. March 2016. When the TSCA was put into place, all existing chemicals were considered to be safe for use and subsequently grandfathered in. Its three main objectives are to assess and regulate new commercial chemicals before they enter the market, to regulate chemicals already existing in 1976 that posed an "unreasonable risk of injury to health or the environment", as for example PCBs, lead, mercury and radon, and to regulate these chemicals' distribution and use. Contrary to what the name implies, TSCA does not se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harvard T
Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher learning in the United States and one of the most prestigious and highly ranked universities in the world. The university is composed of ten academic faculties plus Harvard Radcliffe Institute. The Faculty of Arts and Sciences offers study in a wide range of undergraduate and graduate academic disciplines, and other faculties offer only graduate degrees, including professional degrees. Harvard has three main campuses: the Cambridge campus centered on Harvard Yard; an adjoining campus immediately across Charles River in the Allston neighborhood of Boston; and the medical campus in Boston's Longwood Medical Area. Harvard's endowment is valued at $50.9 billion, making it the wealthiest academic institution in the world. Endowment inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Institute For Occupational Safety And Health
The National Institute for Occupational Safety and Health (NIOSH, ) is the United States federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness. NIOSH is part of the Centers for Disease Control and Prevention (CDC) within the U.S. Department of Health and Human Services. Despite its name, it is not part of the National Institutes of Health. Its current director is John Howard. NIOSH is headquartered in Washington, D.C., with research laboratories and offices in Cincinnati, Ohio; Morgantown, West Virginia; Pittsburgh, Pennsylvania; Denver, Colorado; Anchorage, Alaska; Spokane, Washington; and Atlanta, Georgia. NIOSH is a professionally diverse organization with a staff of 1,200 people representing a wide range of disciplines including epidemiology, medicine, industrial hygiene, safety, psychology, engineering, chemistry, and statistics. The Occupational Safety and Health Act, signed by President Rich ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liver Disease
Liver disease, or hepatic disease, is any of many diseases of the liver. If long-lasting it is termed chronic liver disease. Although the diseases differ in detail, liver diseases often have features in common. Signs and symptoms Some of the signs and symptoms of a liver disease are the following: * Jaundice * Confusion and altered consciousness caused by hepatic encephalopathy. * Thrombocytopenia and coagulopathy. * Risk of bleeding symptoms particularly taking place in gastrointestinal tract Liver diseases File:Ground glass hepatocytes high mag cropped 2.jpg, Ground glass hepatocytes File:Primary biliary cirrhosis intermed mag much cropping.jpg, Primary biliary cirrhosis File:Buddchiari2.PNG, Budd-chiari syndrome File:Non-alcoholic_fatty_liver_disease1.jpg, Micrograph of non-alcoholic fatty liver disease There are more than a hundred different liver diseases. Some of the most common are: * Fascioliasis, a parasitic infection of liver caused by a liver fluke of the genus '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
