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47-583: [REDACTED] Look up tcap in Wiktionary, the free dictionary. TCAP may refer to: Science [ edit ] Acetone peroxide , the trimer version tri-cyclic acetone peroxide , a high explosive Telethonin , a protein encoded by the TCAP gene Education [ edit ] Tennessee Comprehensive Assessment Program , a public school standardized testing program Transitional Colorado Assessment Program,

94-487: A bond dissociation energy of 45–50  kcal/mol (190–210  kJ/mol ), less than half the strengths of C−C, C−H, and C−O bonds. Peroxides play important roles in biology. Hundreds of peroxides and hydroperoxides are known, being derived from fatty acids, steroids, and terpenes. The prostaglandins are biosynthesized by initial formation of a bicyclic peroxide ("endoperoxide") derived from arachidonic acid . Many aspects of biodegradation or aging are attributed to

141-739: A radical initiators , e.g., to enable polymerization of acrylates. Industrial resins based on acrylic and/or methacrylic acid esters are invariably produced by radical polymerization with organic peroxides at elevated temperatures. The polymerization rate is adjusted by suitable choice of temperature and type of peroxide. Methyl ethyl ketone peroxide , benzoyl peroxide and to a smaller degree acetone peroxide are used as initiators for radical polymerization of some thermosets , e.g. unsaturated polyester and vinyl ester resins, often encountered when making fiberglass or carbon fiber composites (CFRP), with examples including boats, RV units, bath tubs, pools, sporting equipment, wind turbine blades, and

188-465: A Predator , American reality television news segment of Dateline NBC , which used hidden cameras to catch child sex predators Transaction Capabilities Application Part (ITU-T Q.771-Q.775 or ANSI T1.114 ) a protocol to allow multiple simultaneous dialogs on the same subsystem Catholic Tercio of Political Action Party (Spanish: TCAP) a local political party in Madrid in 2007, see Results breakdown of

235-654: A catalyst. The product made by using hydrochloric acid is regarded as more stable than the one made using sulfuric acid. It is known that traces of sulfuric acid trapped inside the formed acetone peroxide crystals lead to instability. In fact, the trapped sulfuric acid can induce detonation at temperatures as low as 50 °C (122 °F). This is the most likely mechanism behind accidental explosions of acetone peroxide that occur during drying on heated surfaces. Organic peroxides in general are sensitive, dangerous explosives, and all forms of acetone peroxide are sensitive to initiation . TATP decomposes explosively; examination of

282-405: A cold place promptly after the synthesis. 3) The containers are made of non-reactive materials such as stainless steel, some aluminium alloys or dark glass. For safe handling of concentrated organic peroxides, an important parameter is temperature of the sample, which should be maintained below the self accelerating decomposition temperature of the compound. The shipping of organic peroxides

329-407: A container with a threaded lid. This process of repeated sublimation and deposition also results in a change in crystal size via Ostwald ripening . Several methods can be used for trace analysis of TATP, including gas chromatography/mass spectrometry (GC/MS), high performance liquid chromatography /mass spectrometry (HPLC/MS), and HPLC with post-column derivitization. Acetone peroxide

376-550: A cool, opaque container, as heating and illumination accelerate their chemical reactions . Small amounts of peroxides, which emerge from storage or reaction vessels are neutralized using reducing agents such as iron(II) sulfate . Safety measures in industrial plants producing large amounts of peroxides include the following: 1) The equipment is located within reinforced concrete structures with foil windows, which would relieve pressure and not shatter in case of explosion. 2) The products are bottled in small containers and are moved to

423-464: A melting point of 97 °C (207 °F). In 1899, Adolf von Baeyer and Victor Villiger described the first synthesis of the dimer and described use of acids for the synthesis of both peroxides. Baeyer and Villiger prepared the dimer by combining potassium persulfate in diethyl ether with acetone, under cooling. After separating the ether layer, the product was purified and found to melt at 132–133 °C (270–271 °F). They found that

470-793: A particular set of conditions of reagent and acid catalyst concentration, the cyclic trimer is the primary product. Under neutral conditions, the reaction is reported to produce the monomeric organic peroxide . A tetrameric form has also been described, under different catalytic conditions, albeit not without disputes and controversy. The most common route for nearly pure TATP is H 2 O 2 /acetone/HCl in 1:1:0.25 molar ratios, using 30% hydrogen peroxide. This product contains very little or none of DADP with some very small traces of chlorinated compounds. Product that contains large fraction of DADP can be obtained from 50% H 2 O 2 using large amounts of concentrated sulfuric acid as catalyst or alternatively with 30% H 2 O 2 and massive amounts of HCl as

517-628: A public school standardized testing program that replaced the Colorado Student Assessment Program Finance [ edit ] Tax Credit Assistance Program , a U.S. federal housing grant program Thanachart Capital PCL (stock ticker: TCAP), the holding company of TBank , the Thanachart Bank Other uses [ edit ] Taipei Children's Amusement Park , an amusement park in Taipei, Taiwan To Catch

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564-830: A variety of industrial applications. Benzoyl peroxide , peroxyesters / peroxyketals , and alkylperoxy monocarbonates are used in production of polystyrene , expanded polystyrene , and High Impact Polystyrene , and benzoyl peroxide is utilized for many acrylate based adhesive applications. Thermoplastic production techniques for many industrial polymerization applications include processes which are carried out in bulk, solution, or suspension type batches. Relevant polymers include: polyvinyl chloride (PVC), low-density polyethylene (LDPE), high-density polyethylene (HDPE), polymethyl methacrylate (PMMA), Polystyrene , and Polycarbonates . Benzoyl peroxide and hydrogen peroxide are used as bleaching and "maturing" agents for treating flour to make its grain release gluten more easily;

611-430: Is rubrene . Six-membered cyclic peroxides are called endo peroxides. The four-membered dioxetanes can be obtained by 2+2 cycloaddition of oxygen to alkenes . The hazards associated with storage of ethers in air is attributed to the formation of hydroperoxides via the direct albeit slow reaction of triplet oxygen with C-H bonds . Organic peroxides are widely used to initiate polymerization of olefins , e.g.

658-403: Is about 2800 kJ/kg (measured in helium), enough to briefly raise the temperature of gaseous products to 2,000 °C (3,630 °F). Volume of gases at STP is 855 L/kg for TATP and 713 L/kg for DADP (measured in helium). The tetrameric form of acetone peroxide, prepared under neutral conditions using a tin catalyst in the presence of a chelator or general inhibitor of radical chemistry ,

705-501: Is also efficient in reducing egg production in Schistosoma haematobium infection. tert-Butyl hydroperoxide is used for epoxidation and hydroxylation reagents in conjunction with metal catalysts. Several analytical methods are used for qualitative and quantitative determination of peroxides. A simple qualitative detection of peroxides is carried out with the iodine-starch reaction . Here peroxides, hydroperoxides or peracids oxidize

752-428: Is an organic peroxide and a primary explosive . It is produced by the reaction of acetone and hydrogen peroxide to yield a mixture of linear monomer and cyclic dimer , trimer , and tetramer forms. The monomer is dimethyldioxirane . The dimer is known as diacetone diperoxide ( DADP ). The trimer is known as triacetone triperoxide ( TATP ) or tri-cyclic acetone peroxide ( TCAP ). Acetone peroxide takes

799-399: Is often betrayed by excessive bleach-like or fruity smells. This smell can even penetrate into clothes and hair in amounts that are quite noticeable; this was reported in the 2016 Brussels bombings . Organic peroxide Organic peroxides are classified (i) by the presence or absence of a hydroxyl (-OH) terminus and (ii) by the presence of alkyl vs acyl substituents. One gap in

846-421: Is reported to be more chemically stable, although still a very dangerous primary explosive . Its synthesis has been disputed. Both TATP and DADP are prone to loss of mass via sublimation . DADP has lower molecular weight and higher vapor pressure . This means that DADP is more prone to sublimation than TATP. This can lead to dangerous crystal growth when the vapors deposit if the crystals have been stored in

893-453: Is soluble in toluene, chloroform, acetone, dichloromethane and methanol. Recrystalization of primary explosives may yield large crystals that detonate spontaneously due to internal strain. Ketone peroxides, including acetone peroxide and methyl ethyl ketone peroxide , find application as initiators for polymerization reactions, e.g., silicone or polyester resins , in the making of fiberglass -reinforced composites. For these uses,

940-442: Is the major contaminant found in diisopropyl ether as a result of photochemical oxidation in air. Accidental occurrence at illicit MDMA laboratories is possible. Numerous methods are used to reduce their appearance, including shifting pH to more alkaline, adjusting reaction temperature, or adding inhibitors of their production. TATP has been used in bomb and suicide attacks and in improvised explosive devices, including

987-443: Is useful for comparing the relative concentration of peroxy groups in formulations, which is related to the energy content. In general, energy content increases with active oxygen content, and thus the higher the molecular weight of the organic groups, the lower the energy content and, usually, the lower the hazard. The term active oxygen is used to specify the amount of peroxide present in any organic peroxide formulation. One of

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1034-507: The London bombings on 7 July 2005 , where four suicide bombers killed 52 people and injured more than 700. It was one of the explosives used by the "shoe bomber" Richard Reid in his 2001 failed shoe bomb attempt and was used by the suicide bombers in the November 2015 Paris attacks , 2016 Brussels bombings , Manchester Arena bombing , June 2017 Brussels attack , Parsons Green bombing ,

1081-595: The Surabaya bombings , and the 2019 Sri Lanka Easter bombings . Hong Kong police claim to have found 2 kg (4.4 lb) of TATP among weapons and protest materials in July 2019, when mass protests were taking place against a proposed law allowing extradition to mainland China . TATP shockwave overpressure is 70% of that for TNT, and the positive phase impulse is 55% of the TNT equivalent . TATP at 0.4 g/cm has about one-third of

1128-664: The brisance of TNT (1.2 g/cm ) measured by the Hess test. TATP is attractive to terrorists because it is easily prepared from readily available retail ingredients, such as hair bleach and nail polish remover. It was also able to evade detection because it is one of the few high explosives that do not contain nitrogen , and could therefore pass undetected through standard explosive detection scanners, which were hitherto designed to detect nitrogenous explosives. By 2016, explosives detectors had been modified to be able to detect TATP, and new types were developed. Legislative measures to limit

1175-556: The rate of peroxide decomposition generates heat at a faster rate than it can be dissipated to the environment. Temperature is the main factor in the rate of decomposition. The lowest temperature at which a packaged organic peroxide will undergo a self-accelerating decomposition within a week is defined as the self-accelerating decomposition temperature (SADT). A large fire at the Arkema Chemical Plant in Crosby, Texas (USA) in 2017

1222-458: The 2007 Spanish local elections (Community of Madrid) See also [ edit ] [REDACTED] Search for "tcap" on Misplaced Pages. All pages with titles containing TCAP or TCAPs Traverse City Area Public Schools (TCAPS) Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title TCAP . If an internal link led you here, you may wish to change

1269-406: The added potassium iodide into iodine , which reacts with starch producing a deep-blue color. Commercial paper indicators using this reaction are available. This method is also suitable for quantitative evaluation, but it can not distinguish between different types of peroxide compounds. Discoloration of various indigo dyes in presence of peroxides is used instead for this purpose. For example,

1316-453: The alternative is letting the flour slowly oxidize by air, which is too slow for the industrialized era. Benzoyl peroxide is an effective topical medication for treating most forms of acne . Dialkyl peroxides, e.g., dicumyl peroxide , are synthesized by addition of hydrogen peroxide to alkenes or by O-alkylation of hydroperoxides. Diacyl peroxides are typically prepared by treating hydrogen peroxide with acid chlorides or acid anhydrides in

1363-415: The base-catalyzed Kornblum–DeLaMare rearrangement , which involves the breaking of bonds within peroxides to form these products. Some peroxides are drugs , whose action is based on the formation of radicals at desired locations in the organism. For example, artemisinin and its derivatives, such as artesunate , possess the most rapid action of all current drugs against falciparum malaria . Artesunate

1410-514: The classes of organic peroxides is diphenyl peroxide. Quantum chemical calculations predict that it undergoes a nearly barrierless reaction akin to the benzidine rearrangement . The O−O bond length in peroxides is about 1.45  Å , and the R−O−O angles (R = H, C) are about 110° (water-like). Characteristically, the C−O−O−R (R = H, C) dihedral angles are about 120°. The O−O bond is relatively weak, with

1457-497: The events just behind the detonation front. The authors of the 2004 Dubnikova et al. study confirm that a final redox reaction (combustion) of ozone, oxygen and reactive species into water, various oxides and hydrocarbons takes place within about 180   ps after the initial reaction—within about a micron of the detonation wave. Detonating crystals of TATP ultimately reach temperature of 2,300 K (2,030 °C; 3,680 °F) and pressure of 80 kbar. The final energy of detonation

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1504-554: The explosive decomposition of TATP at the very edge of detonation front predicts "formation of acetone and ozone as the main decomposition products and not the intuitively expected oxidation products." Very little heat is created by the explosive decomposition of TATP at the very edge of the detonation front; the foregoing computational analysis suggests that TATP decomposition is an entropic explosion . However, this hypothesis has been challenged as not conforming to actual measurements. The claim of entropic explosion has been tied to

1551-451: The explosive of choice in several terrorist bomb attacks since 2001. Acetone peroxide (specifically, triacetone triperoxide) was discovered in 1895 by the German chemist Richard Wolffenstein . Wolffenstein combined acetone and hydrogen peroxide , and then he allowed the mixture to stand for a week at room temperature, during which time a small quantity of crystals precipitated, which had

1598-456: The form of a white crystalline powder with a distinctive bleach -like odor when impure, or a fruit-like smell when pure, and can explode powerfully if subjected to heat, friction, static electricity, concentrated sulfuric acid, strong UV radiation, or shock . Until about 2015, explosives detectors were not set to detect non-nitrogenous explosives, as most explosives used preceding 2015 were nitrogen-based. TATP, being nitrogen-free, has been used as

1645-477: The formation and decay of peroxides formed from oxygen in air. Countering these effects, an array of biological and artificial antioxidants destroy peroxides. In fireflies , oxidation of luciferins , which is catalyzed by luciferases , yields a peroxy compound 1,2-dioxetane . The dioxetane is unstable and decays spontaneously to carbon dioxide and excited ketones , which release excess energy by emitting light ( bioluminescence ). Many peroxides are used as

1692-688: The formation of polyethylene . A key step is homolysis : The tendency to homolyze is also exploited to modify polymers by grafting or visbreaking , or cross-link polymers to create a thermoset . When used for these purposes, the peroxide is highly diluted, so the heat generated by the exothermic decomposition is safely absorbed by the surrounding medium (e.g. polymer compound or emulsion ). Especially when in concentrated form, organic peroxides can decompose by self-oxidation, since organic peroxides contain both an oxidizer (the O-O bond) and fuel (C-H and C-C bonds). A "self-accelerating decomposition" occurs when

1739-415: The hydrogen peroxide the anthraquinone is catalytically reduced to anthrahydroquinone and reused in the process. There are other hydroquinones reacting in a similar fashion. Organoperoxides can be reduced to alcohols with lithium aluminium hydride , as described in this idealized equation: The phosphite esters and tertiary phosphines also effect reduction: Cleavage to ketones and alcohols occurs in

1786-499: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=TCAP&oldid=1095550954 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Acetone peroxide Acetone peroxide ( / æ s ə ˈ t ə ʊ n p ɛr ˈ ɒ k s aɪ d / also called APEX and mother of Satan )

1833-453: The loss of blue color in leuco- methylene blue is selective for hydrogen peroxide. Quantitative analysis of hydroperoxides can be performed using potentiometric titration with lithium aluminium hydride . Another way to evaluate the content of peracids and peroxides is the volumetric titration with alkoxides such as sodium ethoxide . Each peroxy group is considered to contain one active oxygen atom. The concept of active oxygen content

1880-413: The oxygen atoms in each peroxide group is considered "active". The theoretical amount of active oxygen can be described by the following equation: where p is the number of peroxide groups in the molecule, and m is the molecular mass of the pure peroxide. Organic peroxides are often sold as formulations that include one or more phlegmatizing agents . That is, for safety sake or performance benefits

1927-540: The peroxides are typically in the form of a dilute solution in an organic solvent; methyl ethyl ketone peroxide is more common for this purpose, as it is stable in storage. Acetone peroxide is used as a flour bleaching agent to bleach and "mature" flour. Acetone peroxides are unwanted by-products of some oxidation reactions such as those used in phenol syntheses. Due to their explosive nature, their presence in chemical processes and chemical samples creates potential hazardous situations. For example, triacetone peroxide

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1974-537: The presence of base: The reaction competes with hydrolysis of the acylating agent but the hydroperoxide anion is a superior nucleophile relative to hydroxide. Unsymmetrical diacyl peroxides can be produced by treating acyl chlorides with the peroxy acid. Peresters , an example being tert -Butyl peroxybenzoate , are produced by treating acid anhydrides or acid chlorides with hydroperoxides. Cyclic peroxides can be obtained by cycloaddition of singlet oxygen (generated by UV radiation) to dienes. An important example

2021-458: The properties of an organic peroxide formulation are commonly modified by the use of additives to phlegmatize (desensitize), stabilize, or otherwise enhance the organic peroxide for commercial use. Commercial formulations occasionally consist of mixtures of organic peroxides, which may or may not be phlegmatized. Peroxides are also strong oxidizers and easily react with skin, cotton and wood pulp. For safety reasons, peroxidic compounds are stored in

2068-564: The sale of hydrogen peroxide concentrated to 12% or higher have been made in the European Union. A key disadvantage is the high susceptibility of TATP to accidental detonation, causing injuries and deaths among illegal bomb-makers, which has led to TATP being referred to as the "Mother of Satan". TATP was found in the accidental explosion that preceded the 2017 terrorist attacks in Barcelona and surrounding areas . Large-scale TATP synthesis

2115-402: The trimer could be prepared by adding hydrochloric acid to a chilled mixture of acetone and hydrogen peroxide. By using the depression of freezing points to determine the molecular weights of the compounds, they also determined that the form of acetone peroxide that they had prepared via potassium persulfate was a dimer, whereas the acetone peroxide that had been prepared via hydrochloric acid

2162-659: Was a trimer, like Wolffenstein's compound. Work on this methodology and on the various products obtained, was further investigated in the mid-20th century by Milas and Golubović. The chemical name acetone peroxide is most commonly used to refer to the cyclic trimer, the product of a reaction between two precursors , hydrogen peroxide and acetone, in an acid- catalyzed nucleophilic addition , although monomeric and dimeric forms are also possible. Specifically, two dimers, one cyclic (C 6 H 12 O 4 ) and one open chain (C 6 H 14 O 4 ), as well as an open dihydroperoxide monomer (C 3 H 8 O 4 ), can also be formed; under

2209-618: Was caused by the decomposition of various organic peroxides following power failure and subsequent loss of cooling systems. This occurred due to extreme flooding from Hurricane Harvey , which destroyed main and back-up power generators at the site. Hydroperoxides are intermediates or reagents in major commercial processes. In the cumene process , acetone and phenol are produced by decomposition of cumene hydroperoxide (Me = methyl): Anthrahydroquinone reacts spontaneously with oxygen to form anthraquinone and hydrogen peroxide, possibly through some organic peroxide intermediate. After extraktion of

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