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Azodicarbonamide
Azodicarbonamide, ADCA, ADA, or azo(''bis'')formamide, is a chemical compound with the molecular formula C2H4O2N4. It is a yellow to orange-red, odorless, crystalline powder. It is sometimes called a 'yoga mat' chemical because of its widespread use in foamed plastics. It was first described by John Bryden in 1959. Synthesis It is prepared in two steps via treatment of urea with hydrazine to form biurea, as described in this idealized equation: :2 OC(NH2)2 + N2H4 → H2NC(O)-N(H)-N(H)-C(O)NH2 + 2 NH3 Oxidation with chlorine or chromic acid yields azodicarbonamide: :H2NC(O)-N(H)-N(H)-C(O)NH2 + Cl2 → H2NC(O)-N=N-C(O)NH2 + 2 HCl Applications Blowing agent The principal use of azodicarbonamide is in the production of foamed plastics as a blowing agent. The thermal decomposition of azodicarbonamide produces nitrogen, carbon monoxide, carbon dioxide, and ammonia gases, which are trapped in the polymer as bubbles to form a foamed article. Azodicarbonamide is used in plastics, sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethylene-vinyl Acetate
Ethylene-vinyl acetate (EVA), also known as poly (ethylene-vinyl acetate) (PEVA), is the copolymer of ethylene and vinyl acetate. The weight percent of vinyl acetate usually varies from 10 to 40%, with the remainder being ethylene. There are three different types of EVA copolymer, which differ in the vinyl acetate (VA) content and the way the materials are used. The EVA copolymer which is based on a low proportion of VA (approximately up to 4%) may be referred to as vinyl acetate modified polyethylene. It is a copolymer and is processed as a thermoplastic material – just like low density polyethylene. It has some of the properties of a low density polyethylene but increased gloss (useful for film), softness and flexibility. The material is generally considered non-toxic. The EVA copolymer, which is based on a medium proportion of VA (approximately 4 to 30%), is referred to as thermoplastic ethylene-vinyl acetate copolymer and is a thermoplastic elastomer material. It is not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dough Conditioner
A dough conditioner, flour treatment agent, improving agent or bread improver is any ingredient or chemical added to bread dough to strengthen its texture or otherwise improve it in some way. Dough conditioners may include enzymes, yeast nutrients, mineral salts, oxidants and reductants, bleaching agents and emulsifiers. They are food additives combined with flour to improve baking functionality. Flour treatment agents are used to increase the speed of dough rising and to improve the strength and workability of the dough. While they are an important component of modern factory baking, some small-scale bakers reject them in favour of longer fermentation periods that produce greater depth of flavour. These agents are often sold as mixtures in a soy flour base, as only small amounts are required. Examples Examples of dough conditioners include ascorbic acid, distilled monoglycerides, citrate ester of monoglycerides, diglycerides, ammonium chloride, enzymes, diacetyl tartaric aci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
E Number
E numbers ("E" stands for "Europe") are codes for substances used as food additives, including those found naturally in many foods such as vitamin C, for use within the European Union (EU) and European Free Trade Association (EFTA). Commonly found on food labels, their safety assessment and approval are the responsibility of the European Food Safety Authority (EFSA). The fact that an additive has an E number implies that its use was at one time permitted in products for sale in the European Single Market; some of these additives are no longer allowed today. Having a single unified list for food additives was first agreed upon in 1962 with food colouring. In 1964, the directives for preservatives were added, in 1970 antioxidants were added, in 1974 emulsifiers, stabilisers, thickeners and gelling agents were added as well. Numbering schemes The numbering scheme follows that of the International Numbering System for Food Additives, International Numbering System (INS) as determ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flour Bleaching Agent
Flour bleaching agent is the agent added to fresh milled grains to whiten the flour by removing the yellow colour pigment called xanthophyll. It whitens the flour, which is used in the baking industry. Overview Usual flour bleaching agents are: *Organic peroxides (benzoyl peroxide) *Calcium peroxide *Chlorine *Chlorine dioxide * Azodicarbonamide *Nitrogen dioxide *Atmospheric oxygen, used during natural aging of flour Use of chlorine, bromates, and peroxides is not allowed in the European Union. Bleached flour improves the structure-forming capacity, allowing the use of dough formulas with lower proportions of flour and higher proportions of sugar . In biscuit making, use of chlorinated flour reduces the spread of the dough, and provides a "tighter" surface. The changes of functional properties of the flour proteins are likely to be caused by their oxidation. In countries where bleached flour is prohibited, microwaving plain flour produces similar chemical changes to the bleach ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semicarbazide
Semicarbazide is the chemical compound with the formula OC(NH2)(N2H3). It is a water-soluble white solid. It is a derivative of urea. Synthesis The compound prepared by treating urea with hydrazine:Jean-Pierre Schirmann, Paul Bourdauducq "Hydrazine" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2002. . :OC(NH2)2 + N2H4 → OC(NH2)(N2H3) + NH3 A further reaction can occur to give carbohydrazide: :OC(NH2)(N2H3) + N2H4 → OC(N2H3)2 + NH3 Derivatives Semicarbazide is frequently reacted with aldehydes and ketones to produce semicarbazones via a condensation reaction. This is an example of imine formation resulting from the reaction of a primary amine with a carbonyl group. The reaction is useful because semicarbazones, like oximes and 2,4-DNPs, typically have high melting points and crystallize, facilitating purification or identification of reaction products. Properties Semicarbazide products (semicarbazones and thiosemicarbazones) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biurea
Biurea is a chemical compound with the molecular formula C2H6N4O2. It is produced in food products containing azodicarbonamide, a common ingredient in bread flour, when they are cooked. Upon exposure, biurea is rapidly eliminated from the body through excretion. Biurea is produced from urea and hydrazine by transamidation. Its major use is as a chemical intermediate in the production of azodicarbonamide, a common blowing agent A blowing agent is a substance which is capable of producing a cellular structure via a foaming process in a variety of materials that undergo hardening or phase transition, such as polymers, plastics, and metals. They are typically applied when .... References {{reflist External links Biurea NLM Hazardous Substances Data Bank Semicarbazides Ureas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Official Journal Of The European Union
An official is someone who holds an office (function or mandate, regardless whether it carries an actual working space with it) in an organization or government and participates in the exercise of authority, (either their own or that of their superior and/or employer, public or legally private). An elected official is a person who is an official by virtue of an election. Officials may also be appointed '' ex officio'' (by virtue of another office, often in a specified capacity, such as presiding, advisory, secretary). Some official positions may be inherited. A person who currently holds an office is referred to as an incumbent. Something "official" refers to something endowed with governmental or other authoritative recognition or mandate, as in official language, official gazette, or official scorer. Etymology The word ''official'' as a noun has been recorded since the Middle English period, first seen in 1314. It comes from the Old French ''official'' (12th century), from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Union
The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been described as a ''sui generis'' political entity (without precedent or comparison) combining the characteristics of both a federation and a confederation. Containing 5.8per cent of the world population in 2020, the EU generated a nominal gross domestic product (GDP) of around trillion in 2021, constituting approximately 18per cent of global nominal GDP. Additionally, all EU states but Bulgaria have a very high Human Development Index according to the United Nations Development Programme. Its cornerstone, the Customs Union, paved the way to establishing an internal single market based on standardised legal framework and legislation that applies in all member states in those matters, and only those matters, where the states have agree ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substance Of Very High Concern
A substance of very high concern (SVHC) is a chemical substance (or part of a group of chemical substances) concerning which it has been proposed that use within the European Union be subject to authorisation under the REACH Regulation. Indeed, listing of a substance as an SVHC by the European Chemicals Agency (ECHA) is the first step in the procedure for authorisation or restriction of use of a chemical. The first list of SVHCs was published on 28 October 2008 and the list has been updated many times to include new candidates. The most recent update occurred in January 2022 to include a total of 223 SVHC. Criteria The criteria are given in article 57 of the REACH Regulation. A substance ''may'' be proposed as an SVHC if it meets one or more of the following criteria: *it is carcinogenic; *it is mutagenic; *it is toxic for reproduction; *it is persistent, bioaccumulative and toxicAnnex XIII, REACH Regulation, at pp. 383–85. (PBT substances); *it is very persistent and very bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Registration, Evaluation, Authorisation And Restriction Of Chemicals
Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) is a European Union regulation dating from 18 December 2006. REACH addresses the production and use of chemical substances, and their potential impacts on both human health and the environment. Its 849 pages took seven years to pass, and it has been described as the most complex legislation in the Union's history and the most important in 20 years. It is the strictest law to date regulating chemical substances and will affect industries throughout the world. REACH entered into force on 1 June 2007, with a phased implementation over the next decade. The regulation also established the European Chemicals Agency, which manages the technical, scientific and administrative aspects of REACH. Overview When REACH is fully in force, it will require all companies manufacturing or importing chemical substances into the European Union in quantities of one tonne or more per year to register these substances with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WorkSafe Victoria
WorkSafe Victoria is the trading name of the Victorian WorkCover Authority, a statutory authority of the state government of Victoria, Australia. History After being renamed in 2014 as Victorian Work-cover Authority by Minister Gordon Rich-Phillips, it returned to the WorkSafe trading name after the election of the Labor Government in November 2014. It has had a number of previous names including ''VWA'', ''WorkCare'' and the ''Department of Labour''. The name ''WorkSafe'' became the trading name for the workplace health and safety and workers compensation divisions in mid-2008, as it reflected the objective of encouraging people to work safely and reduce workplace injuries. The organisation reports to a Minister and has Board of Management The Chief Executive is Clare Amies. reviewof WorkSafe and the Geelong Geelong ( ) (Wathawurrung: ''Djilang''/''Djalang'') is a port city in the southeastern Australian state of Victoria, located at the eastern end of Corio Bay (th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
