It is not that HIF-1 alpha is being oxidised, and thus destroyed.
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But those pathways depend on there being oxygen around, because they need oxidised forms of nitrogen to work with.
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The study results also showed that riboflavin, a nutrient found in milk, oxidised in as little as two hours when exposed to fluorescent light.
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Tens of vividly coloured saris hung on the back wall; wooden shelves, packed with oxidised pots, pans, and rumpled clothes occupied the other three.
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Moreover, Dr Jin, Dr Hilton and their colleagues were able to investigate if debris from the landslides had oxidised and thus released carbon back into the atmosphere before getting washed away.
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Entitled Walhalla â€" the Viking paradise â€" the main installation featured a long, poorly-illuminated and narrow room lined with oxidised steel beds draped with dark grey crumpled lead sheets and covers.
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In a study last year they found that ferrous chloride reacted vigorously with airborne hydrogen peroxide that travelled out of a small sample of TATP and that this exposure oxidised the ferrous chloride, turning it from blue-green to yellow-brown.
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Thus, decamethylferrocene is much more easily oxidised than ferrocene and can even be oxidised to the corresponding dication. Ferrocene is often used as an internal standard for calibrating redox potentials in non-aqueous electrochemistry.
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Lavendulan is a rare secondary mineral in the oxidised zone of some copper-arsenic deposits.
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The reversibility of this reaction can be used to synthesize from . Ammonia is oxidised by into .
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PMe3 is easily oxidised to the phosphine oxide with oxygen. It reacts with methyl bromide to give tetramethylphosphonium bromide.
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Unfortunately this exposed pyrite in the soil that oxidised in the open air rendering the soil acid and infertile.
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Similarly, it is also easily alkylated to give phosphonium derivatives. PEt3 is easily oxidised to the phosphine oxide with oxygen.
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Sulfoxylic acid disproportionates into sulfur and hydrogensulfite . Some of this in turn reacts to form thiosulfate . Sulfoxylates are sensitive to air, and will be oxidised by the oxygen in it. Sulfoxylate is oxidised to sulfur dioxide radical anion and then to sulfur dioxide. : + O2 → + : + O2 → SO2 \+ :2 (dithionite) The known sulfoxylate salts include cobalt sulfoxylate CoSO2·3H2O.
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Some of the carbon is oxidised into carbon monoxide, CO, and carbon dioxide, CO2. This also oxidizes impurities in the pig iron. The container is rotated and the processed pig iron can be separated from the oxidised impurities. Before the mid 19th century, pig iron from the blast furnace was made into wrought iron, which is commercially pure iron.
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According to Nicholson, these cyclic species slowly release an oxidised species, RAs(OH)2, that is likely responsible for Salvarsan's antisyphilis properties.
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The oxidised ores, extending up to 130m below ground surface, consist mainly of magnetite, martite and hydrogoethite. Two other oxidised ore types, hydrogoethite/hematite/semi-martite and carbonate/semi-martite, occur sporadically in small amounts in the deposit. Alteration that may be related to the mineralising event has been observed within the host rocks, and includes sericitisation, silicification and carbonisation.
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The tin chloride is oxidised to stannic acid and the gold chloride is reduced to metallic gold forming a colloidal precipitation onto the stannic acid.
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Cutting compound consists of an abrasive suspended in a paste. Like most abrasives, it comes in various grit sizes dependent upon how much matter is to be removed. It is used on automotive paintwork to cut through (abrade) oxidised paint or to polish out scratches in the paintwork. The oxidised paint is duller than fresh paint and the cutting compound is used to expose this fresher surface.
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A functioning phosphorus getter looks very much like an oxidised metal getter, although it has an iridescent pink or orange appearance which oxidised metal getters lack. Phosphorus was frequently used before metallic getters were developed. In systems which need to be opened to air for maintenance, a titanium sublimation pump provides similar functionality to flashed getters, but can be flashed repeatedly. Alternatively, nonevaporable getters may be used.
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The Grenache vins doux naturels can be made in an oxidised or unoxidised style whereas the Muscat wines are protected from oxidation to retain their freshness.
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Nicotinamide adenine dinucleotide phosphate is a coenzyme present in redox and biosynthetic reactions. The domain binds NADP in its oxidised or reduced forms as NADP+ or NADPH respectively.
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It was renovated in 2004, at the cost of €1.7 million, but by 2010 it was starting to decay again, with cracks in tiles caused by oxidised metal nails.
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Succinic semialdehyde (SSA) is a GABA metabolite. It is formed from GABA by the action of GABA transaminase and further oxidised to become succinic acid, which enters TCA cycle.
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PoCl2 dissolves in dilute hydrochloric acid to give a pink solution, which autoxidises to Po(IV). PoCl2 is rapidly oxidised by hydrogen peroxide or chlorine water. Addition of potassium hydroxide to the pink solution results in a dark brown precipitate – possibly hydrated PoO or Po(OH)2 – which is rapidly oxidised to Po(IV). With dilute nitric acid, PoCl2 forms a dark red solution followed by a flaky white precipitate of unknown composition.
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A noticeable difference between the Trentino and Tuscan examples is that the Trentino wines are usually less oxidised due to the wines regularly being "topped up" to prevent a large ullage.
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The apron zone is generally more oxidised, with stratiform, laminated sulfidic sediments, similar to SEDEX ores, and is generally manganese, barium and hematite enriched, with cherts, jaspers and chemical sediments common.
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The less oxidised the coal the less potassium humate extracted. Sources low in ash produce the best quality. Less oxidised brown coal contains a higher proportion of the insoluble humin fraction and along with peat which is lower in humic acid content and usually high in ash content requires separation by filtration or centrifugation to remove ash, humin. Peat is also high in non humified organic matter that needs to be reduced to produce a high quality product.
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Sulfoxylic acid has been detected in the gas phase. It is likely to be formed as an intermediate when hydrogen sulfide is oxidised by living organisms, or in the atmosphere, or anywhere else in the natural environment. It may also exist in circumstellar disks. When H2S is oxidised it starts from oxidation state −2, and should then pass through intermediate values of 0 and +2 before getting to well known sulfite at +4 and sulfate at +6.
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It is an ill-smelling, toxic compound. Phosphorus has an oxidation number of -3 in phosphine. Phosphine is produced by hydrolysis of calcium phosphide, Ca3P2. Unlike ammonia, phosphine is oxidised by air.
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Most of the active compound is excreted by the kidneys (92–93%). A small proportion is glucuronidated, oxidised, N-formylated or conjugated to a hexose. The elimination half-life is about 24 hours.
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The Decline of the Copper Industry in Chile and the Entrance of North ... By Joanne Fox Przeworski View of the wall. The Guggenheims sold the mine to Anaconda Copper in 1923. Production for many years came from the oxidised capping of the orebody which merely required leaching and then electrowinning of the copper, but by 1951 the oxidised reserves were largely exhausted and the company built a mill, flotation plant and smelter to treat the huge reserves of underlying supergene copper sulfides.
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However, the metallic silver image formed in the first developer, which is a negative image, is not a part of the reaction that takes place in this step. What is being reacted in this stage is the "leftover" of the negative image, that is, a positive image. As the colour development progresses, metallic silver image is formed, but more importantly, the colour developing agent is oxidised. Oxidised colour developer molecules react with the couplers to form colour dyes in situ.
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Oxidation of mesitylene with nitric acid affords trimesic acid, C6H3(COOH)3. Using manganese dioxide, a milder oxidising agent, 3,5-dimethylbenzaldehyde is formed. Mesitylene is oxidised by trifluoroperacetic acid to produce mesitol (2,4,6-trimethylphenol).
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Oxidation (link is dead). Wine International. URL accessed on 2 April 2006. Apart from phenolic oxidation, the ethanol present within wine can also be oxidised into other compounds responsible for flavour and aroma taints.
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Uranous is the chemical term for the reduced tetrapositive cation of uranium that exhibits the valence U4+. It is one of the two common ionic states of uranium found in nature, the other being the oxidised hexapositive ion called uranyl. Uranous compounds are usually unstable; they revert to the oxidised form on exposure to air. Examples of these compounds include uranium tetrachloride (UCl4) and uranium tetrafluoride (UF4), which are important in molten salt reactor applications, and uranium dioxide (UO2), a common form of nuclear fuel.
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Without Erv1 activity, reduced Mia40 accumulates and is in inactive conformation. Interaction between the incoming precursor proteins, Mia40 and Erv1, is maintained as a result of a flow of electrons that are transferred from the incoming protein to Mia40 and from reduced Mia40 to oxidised Erv1. Precursors are then released in oxidised state and form disulfide bridges which prevents their escape out of the intermembrane space. Small Tim proteins are then maintained in active conformation within the intermembrane space by Hot13 (helper of Tims).
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Inertinite is considered to be the equivalent of charcoal and degraded plant material. It is highly oxidised in nature and may be said to be burnt. A large portion of South Africa's coal reserves consist of inertinite.
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The increased level of bioturbation meant that sulfur, which is steadily supplied to the oceanic system from volcanoes and river runoff, was more readily oxidised - rather than being rapidly buried and sitting in its reduced form (sulfide), burrowing organisms continually exposed it to oxygen, allowing it to be oxidised to sulfate. This activity is suggested to account for a sudden rise in sulfate concentration observed near the base of the Cambrian; this can be recorded in the geochemical record both by using isotopic tracers, and by quantifying the abundance of the sulfate mineral gypsum.
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The structure of apolipoprotein(a) is similar to plasminogen and tPA (tissue plasminogen activator) and it competes with plasminogen for its binding site, leading to reduced fibrinolysis. Also, because Lp(a) stimulates secretion of PAI-1, it leads to thrombogenesis. It also may enhance coagulation by inhibiting the function of tissue factor pathway inhibitor. Moreover, Lp(a) carries atherosclerosis-causing cholesterol and binds atherogenic pro-inflammatory oxidised phospholipids as a preferential carrier of oxidised phospholipids in human plasma, which attracts inflammatory cells to vessel walls and leads to smooth muscle cell proliferation.
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Tea leaves can be processed in different ways resulting in a drink which appears and tastes different. Chinese yellow and green tea are steamed, roasted and dried; Oolong tea is semi-oxidised and appears green-black and black teas are fully oxidised. Around the world, people refer to other herbal infusions as "teas"; it is also argued that these were popular long before the Camellia sinensis shrub was used for tea making. Leaves, flowers, roots or bark can be used to make a herbal infusion and can be bought fresh, dried or powdered.
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Posnjakite is an uncommon but widespread secondary mineral in the oxidised zone of copper sulfide deposits, which may be of post-mine formation. It is associated with brochantite, langite, devilline, serpierite, woodwardite, wroewolfeite, aurichalcite, azurite, malachite and chalcopyrite.
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Polonium dibromide forms purple solutions in hydrobromic acid (prepared similarly to solutions of polonium dichloride) and ketones, although the latter are rapidly oxidised to polonium(IV). Solid polonium dibromide is rapidly reduced to metallic polonium upon reaction with ammonia.
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94–96 °C. On oxidation with permanganate in dilute sulfuric acid, propionaldehyde and succinic acid are produced, whilst the saturated substance, mp. 94–96 °C, is oxidised to n-valeric acid. These results indicate that the substance of mp.
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They became known as the Austerity Games. Many British athletes commuted to the Games on public transport. Even the "gold" medals were made from oxidised silver. However, each national team was assigned a vehicle with a uniformed female driver.
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This leaves a ketone, as R1–COR2. Ketones cannot normally be oxidised any further because this would involve breaking a C–C bond, which requires too much energy.Burton, George et al. (2000). Salters Advanced Chemistry: Chemical (2nd ed.). Heinemann.
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A variety of other synthetic methods have been published. Salts of the dodecaborate ion are stable in air and do not react with hot aqueous sodium hydroxide or hydrochloric acid. The anion can be electrochemically oxidised to [B24H23]3−.
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The powder was delivered as a raw material to the paint industry where it was mixed with water, then boiled and oxidised to form a red pigment, also known as brazilwood which in turn was used as a textile dye.
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The structure of a cobalt(IV) coordination complex with the norbornyl anion Reaction of the anhydrous compound with sodium cyclopentadienide gives cobaltocene . This 19-electron species is a good reducing agent, being readily oxidised to the yellow 18-electron cobaltacenium cation .
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A secondary alcohol can be oxidised into a ketone using acidified potassium dichromate and heating under reflux. The orange-red dichromate ion, Cr2O72−, is reduced to the green Cr3+ ion. This reaction was once used in an alcohol breath test.
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The domain is associated with the oxidoreductase family and acts on NADH or NADPH, using a heme protein as an electron acceptor. Requires FAD and FMN as cofactors to catalyse the reaction: NADPH + H+ + n oxidised hemoprotein = NADP+ + n reduced hemoprotein.
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A small amount of sulfur dioxide () is added to prevent substance abuse. Multiple washes through a base (such as sodium hydroxide) can remove this, decreasing the corrosive properties observed when is further oxidised during combustion into sulfuric acid, making emissions cleaner.
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One ancient process for extracting the silver from lead was cupellation. Lead was melted in a bone ash 'test' or 'cupel' and air blown across the surface. This oxidised the lead to litharge, and also oxidised other base metals present, the silver (and gold if present) remaining unoxidised.Metallurgy - An Elementary Text Book, E.L. Rhead F.I.C F.C.S, Longmans, 1895, pp225-229 In the 18th century, the process was carried on using a kind of reverberatory furnace, but differing from the usual kind in that air was blown over the surface of the molten lead from bellows or (in the 19th century) blowing cylinders.
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The repeated, saturated exposure to air oxidises the skin and flesh of the fruit, turning it black in an artificial process that mimics natural ripening. Once fully oxidised or "blackened", they are brined and acid corrected and are then ready for eating.
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This process oxidised the silicon to form a slag, which floated on the iron and was removed by lowering a dam at the end of the trough. The product of this process was a white metal, known as finers metal or refined iron.
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Periodates are powerful oxidising agents. They can oxidise catechol to 1,2-benzoquinone and hydroquinone to 1,4-benzoquinone. Sulfides can be effectively oxidised to sulfoxides. Periodates are sufficiently powerful to generate other strong inorganic oxidisers such as permanganate, osmium tetroxide and ruthenium tetroxide.
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Hoplite armour exhibit from the Archaeological Museum of Corfu. Note the gold inserts around the chest area of the iron breastplate at the centre of the exhibit. The helmet on the upper left is a restored version of the oxidised helmet on the right.
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Licarbazepine is metabolised by conjugation with Glucuronic acid. Approximately 4% are oxidised to the inactive 10,11-dihydroxy derivative. Elimination is almost completely renal, with faeces accounting to less than 4%. 80% of the excreted substances are to be attributed to licarbazepine or its glucuronides.
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Accessed 21 October 2013. Other handicrafts include: hand block printing of textiles; silver, bead and paste jewellery crafting; pottery; wood carving and lacquerware; brass sheet work and oxidised silver artwork;and lace and embroidery making."Maharashtra development report." Government of India Planning Commission report.
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Arsenate reductase (azurin) () is an enzyme that catalyzes the chemical reaction :arsenite + H2O + 2 azurinox \rightleftharpoons arsenate + 2 azurinred \+ 2 H+ The 3 substrates of this enzyme are arsenite, water, and oxidised azurin, whereas its 3 products are arsenate, reduced azurin, and hydrogen ion.
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Oxidised silicon is quartz, i.e. silicon dioxide, the primary component of glass. In high voltage systems containing transformers and capacitors, liquid insulator oil is the typical method used for preventing arcs. The oil replaces air in spaces that must support significant voltage without electrical breakdown.
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The lighter (lower ) methanogenic carbon can only be incorporated into the forams' shells after it has been oxidised. A gradual release of the gas would allow it to be oxidised in the deep ocean, which would make benthic forams show lighter values earlier. The fact that the planktonic forams are the first to show the signal suggests that the methane was released so rapidly that its oxidation used up all the oxygen at depth in the water column, allowing some methane to reach the atmosphere unoxidised, where atmospheric oxygen would react with it. This observation also allows us to constrain the duration of methane release to under around 10,000 years.
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The formation of hematitic jasperoids is considered to be the product of highly oxidised metasomatism of the wall rocks to a shear zone. The presence of carbonate alteration, talc-carbonated high-magnesian basalts and ultramafic rocks and the remnant mineralogy being restricted to hematite, silica, and sulfides indicates oxidising fluid chemistry. Relict volcaniclastic textures in some jasperoids indicate that aluminosilicates have been replaced pervasively by silica + hematite. Transitional forms and poorly developed analogs are present in some gold camps within the Yilgarn craton where deep, reduced methane and carbonate bearing alteration fluids mix with shallower oxidised fluids, resulting in purple-pinkish carbonate flooding alteration within basalts and ultramafic rocks.
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Wetlands and freshwater ecosystems are predicted to be the largest potential contributor to a global methane climate feedback. Long-term warming changes the balance in the methane-related microbial community within freshwater ecosystems so they produce more methane while proportionately less is oxidised to carbon dioxide.
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The oxidised beer presents the mouldy taste of old newspapers. Beer with 100% oxygen exposure has the fastest oxidation rate. Temperature is another cause of oxidation, which produces a lot of oxygen in a high-temperature environment. This oxygen also accelerates the price of beer oxidation.
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One does not expect here intensive stone-robbing. No evidence of stone robbing (“white spaces”) between oxidised stones. The site consists of a distribution of scattered house ruins, is simple. Downhill to the north-west there is loose row of mostly natural defences, not continuous building.
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Increased concentrations of 8-oxoguanine in body fluids have been found to be associated with increased risk of mutagenesis and carcinogenesis. Care must be taken in the assay of 8-oxoguanine due to the ease with which it can be oxidised during extraction and the assay procedure.
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SnF2 is a reducing agent, with a standard reduction potential of Eo (SnIV/ SnII) = +0.15 V. Solutions in HF are readily oxidised by a range of oxidizing agents (O2, SO2 or F2) to form the mixed-valence compound Sn3F8 (containing SnII and SnIV and no Sn–Sn bonds).
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Variants include homoatromentic acid. This pigment has been studied and elucidated by Wolfgang Steglich and colleagues over decades. When atromentin is oxidised with hydrogen peroxide a yellow product is produced. A sodium hydroxide solution is also yellow, but when this is neutralized with acid the red atromentic acid crystallises.
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An intermediate in this reaction is two molecules of dimethylborylhydroperoxide (CH3)2BOOH. (CAS 41557-62-5) When methyldiborane is oxidised around 150 °C a similar substance methyltrioxadiboralane is produced. At the same time dimethyltrioxadiboralane and trimethylboroxine are also formed, and also hydrocarbons, diborane, hydrogen, and dimethoxyborane (dimethyl methylboronic ester).
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Impaired reduction of an oxidised cobalt atom in the active site of MTR is associated with this condition, where enzyme activity can be corrected with reducing agents. Rare polymorphisms related to this disease include (MTRR):c.1459G>A, (MTRR):c.1623-1624insTA and (MTRR):c.903+469T>C.
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As locomotive development proceeded, larger superheaters were fitted and steam temperatures increased. When the locomotive was coasting, the air passing from the superheater to the cylinders became so hot that it oxidised the cylinder oil and interfered with lubrication. At this point, most railways decided to abandon snifting valves.
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Aqueous stannous chloride is used by many precious metals refining hobbyists and professionals as an indicator of gold and platinum group metals in solutions. Molten SnCl2 can be oxidised to form highly crystalline SnO2 nanostructures.A.R.Kamali, Thermokinetic characterisation of tin(11) chloride, J Therm Anal Calorim 118(2014) 99-104.
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Formamidopyrimidine-DNA glycosylases (Fpg, MutM) is a trifunctional DNA base excision repair enzyme that removes a wide range of oxidation-damaged bases (N-glycosylase activity; ) and cleaves both the 3'- and 5'-phosphodiester bonds of the resulting apurinic/apyrimidinic site (AP lyase activity;). Fpg has a preference for oxidised purines, excising oxidised purine bases such as 7,8-dihydro-8-oxoguanine (8-oxoG). Its AP (apurinic/apyrimidinic) lyase activity introduces nicks in the DNA strand, cleaving the DNA backbone by beta-delta elimination to generate a single-strand break at the site of the removed base with both 3'- and 5'-phosphates. Fpg is a monomer composed of 2 domains connected by a flexible hinge.
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Joining sherds that are oxidised to different degrees, from the Areopagus; probably used as test pieces to check whether full reduction was achieved (left fully oxidised; right insufficient) At about 900 °C, the oxygen supply is cut, creating reducing conditions, so that red hematite Fe2O3 turns to matte-black iron oxide FeO, and the black slip turns to deep black magnetite Fe3O4. In antiquity this could be achieved through closing the air supply openings and adding non-dried brushwood and green wood, which would only burn incompletely, producing carbon monoxide (CO rather than CO2).In modern electrical ovens, wet sawdust can be added for this purpose. See Gustav Weiß: Keramiklexikon, entry "Reduktion im Elektroofen".
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PON1 was first discovered through its ability to hydrolyse and therefore detoxify organophosphorus compounds which are widely used as pesticides and nerve gases. Despite decades of research it is only now becoming clear that PON1 protects humans from the acute and chronic harmful effects of these compounds Low PON1 activity found in children may increase their susceptibility to organophosphates. Oxidised-lipids are the major cause of inflammation and are responsible for the initiation and/or propagation of several inflammatory diseases including atherosclerosis (heart disease and stroke), diabetes, liver and kidney diseases, rheumatic diseases, eye diseases (macular degeneration), cancer and HIV infection . Because of its ability to destroy oxidised-lipids PON1 appears to play some role in all these diseases.
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Under very oxidising or very reducing conditions, the steady-state catalytic current sometimes tends to a limiting value (a plateau) which (still provided there is no mass transport limitation) relates to the activity of the fully oxidised or fully reduced enzyme, respectively. If interfacial electron transfer is slow and if there is a distribution of electron transfer rates (resulting from a distribution of orientations of the enzymes molecules on the electrode), the current keeps increasing linearly with potential instead of reaching a plateau; in that case the limiting slope is proportional to the turnover rate of the fully oxidised or fully reduced enzyme. The change in steady-state current against potential is often complex (e.g. not merely sigmoidal).
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Extracellularly, IL-33 is rapidly oxidised. The oxidation process results in the formation of two disulphide bridges and a change in the conformation of the molecule, which prevents it from binding to its receptor, ST2. This is believed to limit the range and duration of the action of IL-33.
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During the reaction, NADH is being oxidised to NAD+. The decrease in NADH concentration can then measured by UV/vis spectroscopy using a dye. In additional to spectroscopic techniques, biophysical techniques including native non-denaturing mass spectrometry and nuclear magnetic resonance (NMR) spectroscopy have also been applied to study ICL.
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Nigrosene is an outdated trade name for a black dye made from oxidised aniline dispersed in water. It was used as a colourant in shoe polish until the 1940s, and as a dark stain for bedplates, brackets, crank handles, and wood. This name is no longer used in today's trading market.
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For economic and environmental reasons, many of the byproducts of extraction are reclaimed. Sulfur dioxide gas, for example, is captured and turned into sulfuric acid — which can then be used in the extraction process or sold for such purposes as fertiliser manufacture. Oxidised copper ores can be treated by hydrometallurgical extraction.
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The mine tailings are stored behind a dam in a large pool- like area which has an oxidised, solid surface layer. The dam contains over 100,000 cubic metres of very acidic, sulphide-rich tailings. In 1997, there had been no natural plant recolonisation on the tailings for more than 20 years.
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The Shikimate Dehydrogenase Reaction Shikimate Dehydrogenase catalyzes the reversible NADPH-dependent reaction of 3-dehydroshikimate to shikimate. The enzyme reduces the carbon-oxygen double bond of a carbonyl functional group to a hydroxyl (OH) group, producing the shikimate anion. The reaction is NADPH dependent with NADPH being oxidised to NADP+.
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800px Alkenes can also be oxidised and cleaved in the Lemieux–Johnson oxidation. This uses a catalytic loading of osmium tetroxide which is regenerated in situ by the periodate. The overall process is equivalent to that of ozonolysis. 550px Cleavage reactions proceed via a cyclic intermediate called a periodate ester.
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All monosaccharide ketoses are reducing sugars, because they can tautomerize into aldoses via an aldol intermediate, and the resulting aldehyde group can be oxidised, for example in the Tollens' test or Benedict's test. Ketoses that are bound into glycosides, for example in the case of the fructose moiety of sucrose, are nonreducing sugars.
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The total mid oceanic ridge, and hot spot volcanic emissions of carbon dioxide match the loss due to subduction: 2×1011 kg of CO2 per year. In slowly convecting mantle rocks, diamond that slowly rises above 150 km will slowly turn into graphite or be oxidised to carbon dioxide or carbonate minerals.
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As a hydroquinone, gentisic acid is readily oxidised and is used as an antioxidant excipient in some pharmaceutical preparations. In the laboratory, it is used as a sample matrix in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry, and has been shown to conveniently detect peptides incorporating the boronic acid moiety by MALDI.
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The intracellular genetic regulatory mechanisms have evolved to enforce this choice, as fermentation provides a faster anabolic growth rate for the yeast cells than the aerobic respiration of glucose, which favors catabolism. After glucose is depleted, the fermentative product ethanol is oxidised in a noticeably slower second growth phase, if oxygen is available.
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CAN is traditionally used to release organic ligands from metal carbonyls. In the process, the metal is oxidised, CO is evolved, and the organic ligand is released for further manipulation.L. Brener, J. S. McKennis, and R. Pettit "Cyclobutadiene in Synthesis: endo- Tricyclo[4.4.0.02,5]deca-3,8-diene-7,10-dione" Org. Synth. 1976, 55, 43.
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Silicon is preferentially oxidised by oxygen and is added to reduce the formation of weakening metal oxides in the rail rolling and casting procedures. AREA and ASTM specified 0.1 to 0.23 percent silicon. Phosphorus and sulfur are impurities causing brittle rail with reduced impact- resistance. AREA and ASTM specified maximum phosphorus concentration of 0.04 percent.
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Methyldiborane is hydrolyzed in water to methylboronic acid CH3B(OH)2. Methyldiborane reacts with trimethylamine to yield solid derivatives trimethylamine-methylborane (CH3)3N—BHCH3 and trimethylamine- borane (CH3)3N—BH3. Methyldiborane is pyrophoric, spontaneously inflaming when exposed to air. When methyldiborane is oxidised around 150 °C a substance 2-methyl-1,3,4-trioxadiboralane is produced.
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The oxidation of secondary alcohols to ketones is an important oxidation reaction in organic chemistry. 500px Where a secondary alcohol is oxidised, it is converted to a ketone. The hydrogen from the hydroxyl group is lost along with the hydrogen bonded to the second carbon. The remaining oxygen then forms double bonds with the carbon.
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As white phosphorus oxidises it gives out a greenish-white glow. The glow happens as PO is oxidised by one of these reactions: PO + O• → PO2; or PO + O2 →PO2 \+ O•. The possible ways that PO appears in this process is by breakup of the P2O molecule which in turn may come from P4O.
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In oxidations of alcohols or aldehydes into carboxylic acids, chromic acid is one of several reagents, including several that are catalytic. For example, nickel(II) salts catalyze oxidations by bleach (hypochlorite). Aldehydes are relatively easily oxidised to carboxylic acids, and mild oxidising agents are sufficient. Silver(I) compounds have been used for this purpose.
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For example, glycine with two carbons is converted to acetate. In this way, amino acid fermenting microbes can avoid using hydrogen ions as electron acceptors to produce hydrogen gas. Amino acids can be Stickland acceptors, Stickland donors, or act as both donor and acceptor. Only histidine cannot be fermented by Stickland reactions, and is oxidised.
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Dihydrosirohydrochlorin is one of several naturally occurring tetrapyrrole macrocyclic metabolic intermediates in the biosynthesis of vitamin B12 (cobalamin). Its oxidised form, sirohydrochlorin, is precursor to sirohaem, the iron-containing prosthetic group in sulfite reductase enzymes. Further biosynthetic transformations convert sirohydrochlorin to cofactor F430 for an enzyme which catalyzes the release of methane in the final step of methanogenesis.
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A loose-fitting four-pocket service dress jacket was worn, along with baggy knee breeches, puttees, and tan ankle- boots. A heavy woollen greatcoat was worn during cold weather. The uniform was a drab "pea soup" or khaki colour, while all buttons and badges were oxidised to prevent shine. All personnel wore a shoulder title bearing the word "Australia".
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In industry, valeric acid is produced by the oxo process from 1-butene and syngas, forming valeraldehyde, which is oxidised to the final product. :H2 \+ CO + CH3CH2CH=CH2 → CH3CH2CH2CH2CHO → valeric acid It can also be produced from biomass-derived sugars via levulinic acid and this alternative has received considerable attention as a way to produce biofuels.
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Brandsby-type ware is a lightly gritted fabric, generally oxidised to white, pink, pale brown, or reddish-yellow and sometimes with a grey core.Brooks, C.M. 1987. Medieval and Later Pottery from Aldwark and Other Sites, York, 153–154. They are generally finer and sandier, and usually more hard-fired than the earlier and comparable York Glazed Ware.
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Oxidation of carvone can also lead to a variety of products. In the presence of an alkali such as Ba(OH)2, carvone is oxidised by air or oxygen to give the diketone 7. With hydrogen peroxide the epoxide 8 is formed. Carvone may be cleaved using ozone followed by steam, giving dilactone 9, while KMnO4 gives 10.
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In non-phagocytic cells, oxidative burst products are used in intracellular signalling pathways. The generated ROS achieve this via shifting the cell redox state. This may be monitored by the ratio of the antioxidant enzyme glutathione to its oxidised product, glutathione disulphide (GSH:GSSG). Antioxidant enzymes counterbalance redox signalling by eliminating the involved molecules, importantly superoxide anion and nitric oxide.
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Here it is degraded by reaction with hydroxyl radicals and oxygen. CH2FCH2F + OH → CH2FCHF + H2O CH2FCHF + O2 → CH2FCHFO2 peroxy radical CH2FCHFO2 \+ NO → CH2FCHFO alkoxy radical When catalysed by chlorine atoms and oxidised by nitrogen oxides the end product is HCOF which can decompose further to HF and CO. The halflife in air is between 140 and 180 days.
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Phosphorus monoxide can act as a ligand on transition elements such as molybdenum, ruthenium and osmium. The phosphorus forms a triple bond with the metal. The first to be discovered was on a nickel-tungsten cluster. The WNi2P2 cluster was oxidised by a peroxide to yield a μ3-coordination, where each phosphorus atom is bound to three metal atoms.
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Paraffin, microcrystalline and montanwax are the most used fossil natural waxes that are found in emulsions. Synthetic waxes that are used include (oxidised) LDPE and HDPE, maleic anhydride grafted polypropylene and Fischer-Tropsch waxes. A range of different emulsifiers or surfactants are used to emulsify waxes. These can be anionic, cationic or non-ionic in nature.
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Premature oxidation, (sometimes shortened to premox, or POx) is a flaw that occurs in white wines, when the presumably ageworthy wine is expected to be in good condition yet is found to be oxidised and often undrinkable. In particular the affliction has received attention in connection to incidents of whites produced in Burgundy.Steinberger, Mike, Slate.com (July 6, 2005).
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The stream is exposed to ozone and ozone is unstable at atmospheric condition. The ozone (O3) decomposes into oxygen (O2) and more oxygen is dissolved into the stream. The pathogen is oxidised to form carbon dioxide. This process eliminates the odour of the stream but result in slightly acidic product due to the effect of carbon dioxide present .
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Cytidine residues, modified once to m5C (discussed above), can be further modified: either oxidised once for 5-hydroxylmethylcytidine (hm5C), or oxidised twice for 5-formylcytidine (f5C). Arising from the oxidative processing of m5C enacted in mammals by ten-eleven translocation (TET) family enzymes, hm5C is known to occur in all three kingdoms and to have roles in regulation. While 5-hydroxymethylcytidine (hm5dC) is known to be found in DNA in a widespread manner, hm5C is also found in organisms for which no hm5dC has been detected, indicating it is a separate process with distinct regulatory stipulations. To observe the in vivo addition of methyl groups to cytosine RNA residues followed by oxidative processing, mice can be fed on a diet incorporating particular isotopes and these be traced by LC-MS/MS analysis.
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Sirohydrochlorin is derived from a tetrapyrrolic structural framework created by the enzymes deaminase and cosynthetase which transform aminolevulinic acid via porphobilinogen and hydroxymethylbilane to uroporphyrinogen III. The latter is the first macrocyclic intermediate common to haem, chlorophyll, sirohaem and vitamin B12. Uroporphyrinogen III is subsequently transformed by the addition of two methyl groups to form dihydrosirohydrochlorin and this is oxidised to give sirohydrochlorin.
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Like other branched- chain amino acids, the catabolism of valine starts with the removal of the amino group by transamination, giving alpha-ketoisovalerate, an alpha-keto acid, which is converted to isobutyryl-CoA through oxidative decarboxylation by the branched-chain α-ketoacid dehydrogenase complex. This is further oxidised and rearranged to succinyl-CoA, which can enter the citric acid cycle.
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Grazoprevir reaches peak plasma concentrations two hours after oral intake together with elbasvir (variation between patients: 30 minutes to three hours). In hepatitis C patients, steady state concentrations are found after about six days. Plasma protein binding is 98.8%, mainly to albumin and alpha-1-acid glycoprotein. Part of the substance is oxidised in the liver, largely by the enzyme CYP3A4.
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Elbasvir reaches peak plasma concentrations three hours after oral intake together with grazoprevir (variation between patients: three to six hours). In hepatitis C patients, steady state concentrations are found after about six days. Plasma protein binding is over 99.9%, mainly to albumin and alpha-1-acid glycoprotein. Part of the substance is oxidised in the liver, largely by the enzyme CYP3A4.
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An entertainment, shopping, and dining complex based on Walt Disney World's Downtown Disney was designed by Frank Gehry. With its towers of oxidised silver and bronze- coloured stainless steel under a canopy of lights, it opened as Festival Disney. For a projected daily attendance of 55,000, Euro Disney planned to serve an estimated 14,000 people per hour inside the Euro Disneyland park.
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Iron(II) hydroxide or ferrous hydroxide is an inorganic compound with the formula Fe(OH)2. It is produced when iron(II) salts, from a compound such as iron(II) sulfate, are treated with hydroxide ions. Iron(II) hydroxide is a white solid, but even traces of oxygen impart a greenish tinge. The air- oxidised solid is sometimes known as "green rust".
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Degradation is a process that takes place in almost all materials. Conventional polyethylene (PE) and polypropylene (PP) plastics will typically fragment quite quickly, but will then take decades to become biodegradable. OXO-degradable products utilize a catalyst to speed up the fragmentation. Illustration of the OXO-Degradation: A process whereby the conventional polyolefin plastic is first oxidised to short-chain oxygenated molecules.
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The preserve is normally applied to soil when ready, or can be stored unopened for later use. # The preserve is mixed into soil. This exposes it to air, whereupon the lactic acid oxidises to pyruvate, a fundamental energy carrier in biological processes. # The oxidised preserve is soon consumed by the indigenous soil life, ‘disappearing’ within a very few weeks at normal temperatures.
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This process, called carbon outgassing, is the result of carbonated mantle undergoing decompression melting, as well as mantle plumes carrying carbon compounds up towards the crust. Carbon is oxidised upon its ascent towards volcanic hotspots, where it is then released as CO2. This occurs so that the carbon atom matches the oxidation state of the basalts erupting in such areas.
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The type locality is the Susanna Mine at Leadhills, Strathclyde, Scotland, UK. Leadhillite is a secondary mineral found in the oxidised zone of lead deposits associated with cerussite, anglesite, lanarkite, caledonite, linarite and pyromorphite. It may form pseudomorphs after galena or calcite, and conversely calcite and cerussite may form pseudomorphs after leadhillite. Heating leadhillite causes it to reversibly transform into susannite.
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The dithionate (or metabisulfate) anion, , is a sulfur oxoanion derived from dithionic acid, H2S2O6. Its chemical formula is sometimes written in a semistructural format, as [O3SSO3]2−. The sulfur atoms of the dithionate ion are in the +5 oxidation state due to the presence of the S–S bond. Generally dithionates form stable compounds that are not readily oxidised or reduced.
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Also, fireworks manufacturers modify the surface area of solid reactants to control the rate at which the fuels in fireworks are oxidised, using this to create diverse effects. For example, finely divided aluminium confined in a shell explodes violently. If larger pieces of aluminium are used, the reaction is slower and sparks are seen as pieces of burning metal are ejected.
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HClO may oxidise cysteines and methionines via their sulfhydryl groups and sulfur groups respectively. The former leads to the formation of disulfide bonds, inducing protein crosslinking. Both oxidations result in protein aggregation, and ultimately, cell death. Sulfhydryl groups can be oxidised up to three times by three HClO molecules, forming sulfenic acids, sulfinic acids and R–SO3H, which are increasingly irreversible and bactericidal.
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Supercritical water oxidation uses supercritical water as a medium in which to oxidize hazardous waste, eliminating production of toxic combustion products that burning can produce. The waste product to be oxidised is dissolved in the supercritical water along with molecular oxygen (or an oxidising agent that gives up oxygen upon decomposition, e.g. hydrogen peroxide) at which point the oxidation reaction occurs.
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The group had first identified the thymosin sulfoxide as an active factor in culture fluid of cells responding to treatment with a steroid hormone, suggesting that its formation might form part of the mechanism by which steroids exert anti-inflammatory effects. Extracellular thymosin β4 would be readily oxidised to the sulfoxide in vivo at sites of inflammation, by the respiratory burst.
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If wastes are preserved in anoxic environments, the Prussian blue colour may not yet have developed. Exposing these to the air and allowing them to become oxidised lets the colour develop., Fouled Wood-Shavings as "Box" Wastes, Cyanogens and Lampblack When looking for blue billy as a way to indicate the extent of contamination, this time should be allowed for.
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Pseudomalachite is a phosphate of copper with hydroxyl, named from the Greek for “false” and “malachite”, because of its similarity in appearance to the carbonate mineral malachite, Cu2(CO3)(OH)2. Both are green coloured secondary minerals found in oxidised zones of copper deposits, often associated with each other. Pseudomalachite is polymorphous with reichenbachite and ludjibaite. It was discovered in 1813.
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Polyhypophosphates are known containing linear anions, for example Na5P3O8 containing O(PO2)3O5− with a P−P−P chain and Na6P4O10·2H2O containing O(PO2)4O6−, with a P−P−P−P chain. The cyclic anion , (hypohexametaphosphate) where each phosphorus atom has an oxidation state of +3 is formed when a suspension of red phosphorus in KOH is oxidised with bromine.
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UbiD activation by UbiX/prFMN was found to be dependent on oxygen suggesting that the reduced prFMN product of UbiX is oxidised to the catalytically relevant form. Several variations of the oxidised prFMN (prFMNox) cofactor were observed: prFMNiminium, hydroxylated prFMNiminium and prFMNketimine. Determination of the prFMN isomer that was catalytically relevant involved incubation of AnFdc1UbiX with phenylpyruvate (of which a small proportion is α-hydroxycinnamic acid which closely resembles cinnamic acid - a model substrate). Incubation with phenylpyruvate lead to an altered UV-Vis spectrum and reversible enzyme inhibition. The crystal structure of AnFdc1UbiX with phenylpyruvate revealed a bond between C1’ of prFMNiminium and a phenylacetaldehyde adduct – a species that can be formed by decarboxylation of α-hydroxycinnamic acid and tautomerisation of the α-hydroxystyrene prFMNiminium adduct. This observation confirmed that it’s the prFMNiminium that is the catalytically relevant cofactor.
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The Folin–Wu and the Somogyi–Nelson methods are both based on the same principles. In the first step, glucose (or a reducing sugar) is oxidised using a solution of Cu(II) ion, which is reduced to Cu(I) by the process. In the second step, the Cu(I) ions are then oxidised back to Cu(II) using a colourless hetero-polymolybdate complex, which is, in the process, reduced to give the characteristic blue colour. Finally the absorption of the hetero-poly molybdenum blue is measured using a colorimeter and compared to standards prepared from reacting sugar solutions of known concentration, to determine the amount of reducing-sugar present. The Folin–Wu method "A system of blood analysis" O. Folin, H. Wu, The Journal of Biological Chemistry (1920), 41(3), 367 uses a reagent that contains sodium tungstate.
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Haul truck in Chuquicamata in 2016. Mine's waste rock dumped by a giant truck The modern era started when the American engineer Bradley finally developed a method of working low grade oxidised copper ores. In 1910 he approached the lawyer and industrialist Albert C Burrage who sent engineers to examine Chuquicamata. It was the start of copper mining by the Chile Exploration Company of the Guggenheim Group.
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Clinically, enflurane produces a dose-related depression of myocardial contractility with an associated decrease in myocardial oxygen consumption. Between 2% and 5% of the inhaled dose is oxidised in the liver, producing fluoride ions and difluoromethoxy-difluoroacetic acid. This is significantly higher than the metabolism of its structural isomer isoflurane. Enflurane also lowers the threshold for seizures, and should especially not be used on people with epilepsy.
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The type locality is the Tsumeb Mine, Otjikoto Region, Namibia. Type material is conserved in the Department of Natural History, Royal Ontario Museum, Toronto, Ontario, Canada, catalogue number M53150. At localities in the Caldbeck Fells ianbruceite occurs as a late-stage supergene mineral in fractures in partly oxidised sulfide-rich carbonate or quartz-carbonate matrix. The mines of Caldbeck Fells are famous for their supergene minerals.
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Here, the reduced forms are fluorescent and the oxidised forms non-fluorescent. Oxidation reactions can therefore be followed by a decrease in fluorescence and reduction reactions by an increase. Synthetic substrates that release a fluorescent dye in an enzyme- catalyzed reaction are also available, such as 4-methylumbelliferyl-β-D- galactoside for assaying β-galactosidase or 4-methylumbelliferyl-butyrate for assaying Candida rugosa lipase .
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The Weimberg pathway is an oxidative pathway where the D-xylose is oxidized to D-xylono-lactone by a D-xylose dehydrogenase followed by a lactonase to hydrolyze the lactone to D-xylonic acid. A xylonate dehydratase is splitting off a water molecule resulting in 2-keto 3-deoxy- xylonate. A second dehydratase forms the 2-keto glutarate semialdehyde which is subsequently oxidised to 2-ketoglutarate.
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Purple acid phosphatases (PAPs) () are metalloenzymes that hydrolyse phosphate esters and anhydrides under acidic condition. In their oxidised form, PAPs in solution are purple in colour. This is due to the presence of a dinuclear iron centre, to which a tyrosine residue is connected via a charge transfer. This metallic centre is composed of Fe3+ and M, where M is Fe3+, Zn2+, Mg2+ or Mn2+.
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Given that Nb2O5 is the most common and robust compound of niobium, many methods, both practical and esoteric, exist for its formation. The oxide for example, arises when niobium metal is oxidised in air. The oxidation of niobium dioxide, NbO2 in air forms the polymorph, L-Nb2O5.Electrical properties of NbO2 and Nb2O5 at elevated temperature in air and flowing argon, G. C. Vezzoli Phys. Rev.
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Furthermore, according to Fenton chemistry, these transition metal ions can be further oxidised by hydrogen peroxide to generate a highly reactive hydroxyl radical. The formation of hydrogen peroxide and hydroxyl radicals is believed to induce cytotoxicity and apoptosis of cancer cells. Although many in vitro studies have studied hydrogen peroxide generation by ascorbic acid, the pharmacological mechanism of intravenous ascorbic acid in vivo is still unclear.
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The result was spectacular in that the furnace boiled violently. This was a chemical reaction between the oxidised iron in the scale and the carbon dissolved in the pig iron. To his surprise, the resultant puddle ball produced good iron. One big problem with puddling was that almost 50% of the iron was drawn off with the slag because sand was used for the bed.
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The "natural" substrates for PON1 appear to be lactones. However, PON1 has evolved to be a highly promiscuous enzyme capable of hydrolysing a wide variety of substrates such as lactones (including a number of important pharmaceutical agents such as statins), glucuronide drugs, thiolactones, arylesters, cyclic carbonates, organophosphorus pesticides and nerve gases such as sarin, soman and VX, oestrogen esters and lipid peroxides (oxidised lipids).
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The oxidation of wine is perhaps the most common of wine faults, as the presence of oxygen and a catalyst are the only requirements for the process to occur. Oxidation can occur throughout the winemaking process, and even after the wine has been bottled. Anthocyanins, catechins, epicatechins and other phenols present in wine are those most easily oxidised,duToit, W.J. (2005). Oxygen in winemaking: Part I. WineLand.
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Reaction scheme of the photobromination of the methyl group of toluene. Photobromination with elemental bromine proceeds analogous to photochlorination also via a radical mechanism. In the presence of oxygen, the hydrogen bromide formed is partly oxidised back to bromine, resulting in an increased yield.Because of the easier dosage of the elemental bromine and the higher selectivity of the reaction, photobromination is preferred over photochlorination at laboratory scale.
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Fondillón is a special style of wine produced in the Alicante D.O. in Spain. Fondillón is a red wine produced in an oxidised (rancio) style from overripe Monastrell grapes, and is typically semi-sweet. Its alcohol level is similar to many fortified wines, although Fondillón is not fortified. Fondillón is typically bottled and sold after an extended period of aging in barrel (minimum 10 years).
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Gmelin's test is a chemical test used for detecting the presence of bile pigments in urine. It is named after Leopold Gmelin, who introduced the test. Five millilitres of urine is slowly added to five millilitres of concentrated nitric acid in a test-tube. Different coloured rings between the two layers are visible if bile pigments are present as they are oxidised to various chemical products.
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It does not ignite in air until heated to 300 °C and is insoluble in all solvents. It is not attacked by alkali and only slowly reacts with halogens. It can be oxidised by nitric acid to phosphoric acid. If it is heated in an atmosphere of inert gas, for example nitrogen or carbon dioxide, it sublimes and the vapour condenses as white phosphorus.
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Tsumebite is a rare secondary mineral in the oxidised zone of some arsenic- bearing lead-copper deposits, with other lead-bearing phosphates and sulfates. Associated minerals include azurite, smithsonite, malachite, cerussite, mimetite, wulfenite and olivenite. The type locality is the Tsumeb mine, Tsumeb, Otjikoto Region, Namibia. The Handbook of Mineralogy states that the type material was destroyed by bombing, but does not indicate when or where.
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The medal is circular, made of silver-coloured oxidised metal, 36 mm in diameter. The obverse of the medal displays the letters WEU arranged horizontally for "Western European Union". Above the letter E is the letter U and below the letter O. UEO is the acronym for the French equivalent, Union de l'Europe Occidentale. Below the acronyms, arranged along the edge, are ten five pointed stars.
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The brine is first purified and acidified using sulfuric acid, then the iodide present is oxidised to iodine with chlorine. An iodine solution is produced, but is dilute and must be concentrated. Air is blown into the solution to evaporate the iodine, which is passed into an absorbing tower, where sulfur dioxide reduces the iodine. The hydrogen iodide (HI) is reacted with chlorine to precipitate the iodine.
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Elemental iodine hence forms diatomic molecules with chemical formula I2, where two iodine atoms share a pair of electrons in order to each achieve a stable octet for themselves; at high temperatures, these diatomic molecules reversibly dissociate a pair of iodine atoms. Similarly, the iodide anion, I−, is the strongest reducing agent among the stable halogens, being the most easily oxidised back to diatomic I2.Greenwood and Earnshaw, pp. 800–4 (Astatine goes further, being indeed unstable as At− and readily oxidised to At0 or At+, although the existence of At2 is not settled.) The halogens darken in colour as the group is descended: fluorine is a very pale yellow gas, chlorine is greenish-yellow, and bromine is a reddish-brown volatile liquid. Iodine conforms to the prevailing trend, being a shiny black crystalline solid that melts at 114 °C and boils at 183 °C to form a violet gas.
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Madeira wine Madeira is a fortified wine made in the Madeira Islands. The wine is produced in a variety of styles ranging from dry wines which can be consumed on their own as an aperitif, to sweet wines more usually consumed with dessert. Madeira is deliberately heated and oxidised as part of its maturation process, resulting in distinctive flavours and an unusually long lifespan once a bottle is opened.
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The resulting liquid is dried to produce the amorphous crystalline like product which can then be added as a granule to fertiliser. The potassium humate granules by way of chemical extraction lose their hydrophobic properties and are now soluble. Depending on the source material product quality varies. High quality oxidised lignite (brown coal), usually referred to as leonardite, is the best source material for extraction of large quantities of potassium humate.
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There are several Akabori amino acid reactions, which are named after Shirō Akabori (1900–1992), a Japanese chemist. In the first reaction, an α-amino acid is oxidised and undergoes decarboxylation to give an aldehyde at the former α position by heating with oxygen in the presence of a reducing sugar. This reaction is useful for preparing dichlorophthalimido derivatives of peptides for mass spectral analysis. :Image:Reacción de Akabori 1.
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Kukicha (茎茶), or twig tea, also known as bōcha (棒茶), is a Japanese blend made of stems, stalks, and twigs. It is available as a green tea or in more oxidised processing. Kukicha has a unique flavour and aroma among teas, due to its being composed of parts of the tea plant that are excluded from most other teas. Regular kukicha material comes from production of sencha or matcha.
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PPO catalyses the rapid polymerization of o-quinones to produce black, brown or red pigments (polyphenols) that cause fruit browning. The amino acid tyrosine contains a single phenolic ring that may be oxidised by the action of PPOs to form o-quinone. Hence, PPOs may also be referred to as tyrosinases. Common foods producing the enzyme include mushrooms (Agaricus bisporus), apples (Malus domestica), avocados (Persea americana), and lettuce (Lactuca sativa).
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It occurs in lenses and sheets, within the Awband Formation. The thickness of the lenses has been indicated by drilling to be up to 100m, while the depth of mineralisation is untested 180m below surface. There are two main ore groups: unoxidised primary ores and semi-oxidised ores. The primary ores occur below 100 m and consist of magnetite and pyrite, and up to 5% chalcopyrite and pyrrhotite.
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When sulfide in alkaline conditions is oxidised by air in the presence of nickel ions, sulfoxylate concentration first increases to around 5% and then decreases over several days. Polysulfide concentration also grows and then shrinks on a slower timescale reaching about 25% of the sulfide. The sulfur ends up forming thiosulfate. Sulfoxylic acid has been made by ultraviolet irradiation of a mixture of solid H2S and H2O, followed by warming.
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Named Bluff Town, sales were slower than in other areas and the suburb grew slowly. One of the notable characteristics of the Black Rock shoreline is Red Bluff. The bluff's name comes from the oxidised iron in the cliffs which gives off a burnt orange colour. Either side of Red Bluff are many popular beaches and seaside destinations, including Half Moon Bay, a setting for yachting since the 1890s.
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Jin Jun Mei is a celebrated black tea from the Wuyi Mountains in Fujian Province, China developed in 2006. It is made exclusively from the buds plucked in early spring from the tea plant. The buds are subsequently fully oxidised and then roasted to yield a tea that has a sweet, fruity and flowery flavour with a long lasting sweet after-taste. The brew is bright reddish in colour.
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The role of phosphotungstic acid and the mechanism of staining is not fully understood. The active component of haematoxylin is the oxidised form, haematin, although this rarely acknowledged in the literature which refer to haematoxylin staining. Phosphotungstic acid forms a lake with haematin. The make –up of the reagent is uncertain, examination of a year old sample showed there to be three coloured components, blue, red and yellow.
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However, it does not form stable aqueous solutions, due in part to its autopolymerisation, and its tendency to be oxidised by water. Copper hydride reversibly precipitates from pyridine solution, as an amorphous solid. However, repeated dissolution affords the regular crystalline form, which is insoluble. Under standard conditions, molecular copper hydride autopolymerises to form the crystalline form, including under aqueous conditions, hence the aqueous production method devised by Wurtz.
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After eating, this stored bile is discharged into the duodenum. The composition of hepatic bile is (97–98)% water, 0.7% bile salts, 0.2% bilirubin, 0.51% fats (cholesterol, fatty acids, and lecithin), and 200 meq/l inorganic salts. The two main pigments of bile are bilirubin, which is orange–yellow, and its oxidised form biliverdin, which is green. When mixed, they are responsible for the brown color of feces.
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Talmessite is a rare secondary mineral formed typically in the oxidized zone of some hydrothermal mineral deposits, as an alteration product of realgar, orpiment, or Cu–Ni arsenides. Cobalt-rich varieties are found in the oxidised zone of cobalt arsenide deposits. It occurs associated with gaitite, erythrite, annabergite, picropharmacolite, pharmacolite, austinite, fluorite, baryte, aragonite, calcite and dolomite. At the type locality it is associated with aragonite and dolomite.
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Pyocyanin inactivates catalase by reducing its gene’s transcription as well as directly targeting the enzyme itself. Glutathione is an important antioxidant modulated by pyocyanin. In particular the pool of the reduced form is depleted while the oxidised form is promoted by hydrogen peroxide which is not dismutated by catalase. In the cystic fibrosis lung, intracellular pyocyanin converts molecular oxygen to the superoxide free radical by oxidizing NADPH to NADP+.
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The lava changed as water poured on it. Before cooling, the flow of the lava was blocky, covered with volcanic bombs and was a reddish oxidised colour. After cooling, the surface became more jagged and was much more difficult to walk on, and the flow surface turned from black to grey. (Richard & James, 1983) Water cooling of the lava was slow but efficient, with almost all the water converted to steam.
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The compound can be prepared by reacting phenol with methanol at elevated temperatures over a suitable solid catalyst such as alumina. The mechanism of the process has been studied extensively, with several intermediates having been identified. Alkyne trimerisation of dimethylacetylene also yields hexamethylbenzene in the presence of a suitable catalyst. Hexamethylbenzene can be oxidised to mellitic acid, which is found in nature as its aluminium salt in the rare mineral mellite.
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Nicotinamide occurs as a component of a variety of biological systems, including within the vitamin B family and specifically the vitamin B3 complex. It is also a critically important part of the structures of NADH and NAD+, where the N-substituted aromatic ring in the oxidised NAD+ form undergoes reduction with hydride attack to form NADH. The NADPH/NADP+ structures have the same ring, and are involved in similar biochemical reactions.
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Industrially SO3 is made by the contact process. Sulfur dioxide, which in turn is produced by the burning of sulfur or iron pyrite (a sulfide ore of iron). After being purified by electrostatic precipitation, the SO2 is then oxidised by atmospheric oxygen at between 400 and 600 °C over a catalyst. A typical catalyst consists of vanadium pentoxide (V2O5) activated with potassium oxide K2O on kieselguhr or silica support.
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The sulfur atom in 1,4-oxathiane can undergo reaction as other substituted sulfides can. It can be oxidised to a sulfoxide with calcium hypochlorite or sodium periodate, or continuing to a sulfone. :400px It can react with ammonia to form diimines. With elemental chlorine below 0 °C, 3-chloro-1,4-oxathiane is formed. Above 0 °C, 2,3-dichloro-1,4-oxathiane results and further chlorination yields 2,3,5,6-tetrachloro-1,4-oxathiane.
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Radon compounds can be formed by the decay of radium in radium halides, a reaction that has been used to reduce the amount of radon that escapes from targets during irradiation. Additionally, salts of the [RnF]+ cation with the anions , , and are known. Radon is also oxidised by dioxygen difluoride to at . Radon oxides are among the few other reported compounds of radon; only the trioxide () has been confirmed.
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Most often the rasping of potato tubers is carried out with a rotary grater. The purpose of this stage is disruption of cell walls, which therefore release the starch. In practice, potato cells are not entirely destroyed and part of the starch remains in the mash. Potato pulp rapidly turns dark, because tyrosine presented in the potato is oxidised by polyphenol oxidase, which is located in the cellular juice.
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Temperature also affects the signal response time, which is generally between 6 and 15 seconds at room temperature for a 90% response to a step change in partial pressure. Cold cells react much slower and hot cells much faster. As the anode material is oxidised the output current drops and eventually will cease altogether. The oxidation rate depends on the oxygen reaching the anode from the sensor membrane.
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Functional groups containing heteroatoms in low oxidation states can be oxidised by trifluoroperacetic acid. Common cases include the oxidation of iodine (for example, the formation of the hypervalent iodine compound from iodobenzene mentioned earlier), nitrogen, sulfur, and selenium. In the case of nitrogen-containing compounds, known transformations include oximes and aromatic primary amines to nitro compounds (even with electron-withdrawing substituents, for example, pentafluoroaniline to pentafluoronitrobenzene), nitrosamines to nitramines, formation of aromatic N-oxides and aromatic azine N-oxides, and conversion of nitroso compounds to nitro compounds or nitramines. For example, a mixture of hydrogen peroxide and trifluoroperacetic acid oxidises the nitroso-substituted pyrimidine 4,6-diamino-5-nitrosopyrimidine-2-thiol to its nitro analogue while also removing the thiol moiety by oxidative hydrolytic desulfurization: 500px In the case of chalcogen elements, sulfide moieties (R–S–R) can be oxidised by trifluoroperacetic acid to sulfoxide (R–S(O)–R) and/or sulfone (R–S(O)2–R) forms, depending on the conditions used.
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The painting was cleaned and renovated, revealing the bright green background underneath a layer of oxidised pigment. The identity of the man depicted in the painting is unknown. In 15th-century Italy, the stylistic development of individual portrait-painting had awoken with new vigor after a thousand years of silence. The last period in the history was in the antiquity, when the Romans were known for their prolific depiction of individual traits of peoples.
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The type locality is the Serpieri Mine, Kamariza, Lavrion District, Greece, and type material is conserved at the National Museum of Natural History, Paris, France, reference 73.38, 78.226. Serpierite is a secondary mineral found in altered smelter slags and oxidised sulfide veins. At the type locality it is associated with smithsonite and it has also been found associated with devilline, posnjakite, ktenasite, linarite, langite, brochantite, wroewolfeite, namuwite, schulenbergite, hydrozincite, malachite and gypsum.
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The type locality is the Bloomsberry Horse level of the Brownley Hill mine, Nenthead, Alston Moor District, North Pennines, North and Western Region (Cumberland), Cumbria, England. The type material is conserved at the Royal Museum of Scotland, Edinburgh, Scotland, 1992.17.1–8. Brianyoungite occurs with gypsum on rubbly limestone in the oxidised zone of Brownley Hill Mine, and on specimens from the nearby Smallcleugh mine. It may be a secondary post-mining mineral.
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These were lead and manganese soaps of linseed fatty acids or resin, also termed lineolates or resinates. Terebines had poor shelf life in mixed paints, as they auto-oxidised and lost their effectiveness. As a result, early factory-mixed paints, unless fresh, were a poor substitute for fresh paint mixed by a painter on site from raw ingredients. This situation lasted until the late 1940s; by then further drier developments had superseded the terebines.
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During this process, the vessels in the oven initially lost whatever moisture remained in them. At a temperature of 500 °C, after 6 or 7 hours, true firing of the now red-hot vessels began. With a constant supply of oxygen and a still increasing temperature, the iron-rich shiny slip oxidised and turned red, along with the rest of the vessel. During this process, the iron content is transformed into deep red hematite (Fe2O3).
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The horns and the fleece on its shoulders are of lapis lazuli, and the body's fleece is made of shell, attached to a thicker coat of bitumen. The figure's genitals are gold, while its belly was silver plate, now oxidised beyond restoration. The tree is also covered in gold leaf with gold flowers. The figure stands on a small rectangular base decorated with a mosaic of shell, red limestone and lapis lazuli.
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After the mix is laid down the lighter fraction evaporates. Because of concerns with pollution from the volatile organic compounds in the lighter fraction, cut-back asphalt has been largely replaced by asphalt emulsion. ; Mastic asphalt concrete, or sheet asphalt: This is produced by heating hard grade blown bitumen (i.e., partly oxidised) in a green cooker (mixer) until it has become a viscous liquid after which the aggregate mix is then added.
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Silver staining is used to stain gels. The silver stain of proteins in Agarose gels was developed in 1973 by Kerenyi and Gallyas. Later it was adapted to polyacrylamide gels used in SDS-PAGE, and also for staining DNA or RNA. The glycosylations of glycoproteins and polysaccharides can be oxidised by a 1-hour pre-treatment with 0.1% periodic acid at 4 °C, which improves the binding of silver ions and the staining result.
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The Society for Medieval Archaeology Monograph Series: No 9 The glaze was applied with a brush and can be pale yellow, orange, pale green and smoke blue. This depended on many factors including glaze composition, iron content and whether fired in reduced or oxidised conditions. Examples can be seen at Stamford Museum and elsewhere. Greenish Anglo-Saxon pottery discovered in the town in 1950 suggests lead glaze was in use in early times.
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Catalases are enzymes that catalyse the conversion of hydrogen peroxide to water and oxygen, using either an iron or manganese cofactor. This protein is localized to peroxisomes in most eukaryotic cells. Catalase is an unusual enzyme since, although hydrogen peroxide is its only substrate, it follows a ping-pong mechanism. Here, its cofactor is oxidised by one molecule of hydrogen peroxide and then regenerated by transferring the bound oxygen to a second molecule of substrate.
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The hydrogen peroxide is itself produced by an initial reaction where the glucose is oxidised in the presence of the glucose oxidase catalyst into H2O2 and gluconic acid. The quinone is red-violet in colour, with the intensity of the colour being in proportion to the glucose concentration. The colour is measured at 505 nm, 510 nm, or 540 nm. Diagnostic kits containing the Trinder reagent are available, including one from Sigma-Aldrich.
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Uranium mineralisation is hosted primarily within sheeted leucogranites that intruse the rocks at various stages during the Damara Orogeny. Formation of the uranium magmatic ore body is stratigraphically controlled with the Khan- Rossing boundary acting as a redox front. The abundance of iron oxides and sulfides provide reducing conditions for uranium to be oxidised and precipitate in the form of uraninite which is the primary ore mineral that is mined at Husab.Kinnaird et al.
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Oral cyclophosphamide is rapidly absorbed and then converted by mixed-function oxidase enzymes (cytochrome P450 system) in the liver to active metabolites. The main active metabolite is 4-hydroxycyclophosphamide, which exists in equilibrium with its tautomer, aldophosphamide. Most of the aldophosphamide is then oxidised by the enzyme aldehyde dehydrogenase (ALDH) to make carboxycyclophosphamide. A small proportion of aldophosphamide freely diffuses into cells, where it is decomposed into two compounds, phosphoramide mustard and acrolein.
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Structure of ion Nickel(I) complexes are uncommon, but one example is the tetrahedral complex NiBr(PPh3)3. Many nickel(I) complexes feature Ni-Ni bonding, such as the dark red diamagnetic prepared by reduction of with sodium amalgam. This compound is oxidised in water, liberating . It is thought that the nickel(I) oxidation state is important to nickel-containing enzymes, such as [NiFe]-hydrogenase, which catalyzes the reversible reduction of protons to .
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Reverse electron flow, is the transfer of electrons through the electron transport chain through the reverse redox reactions. Usually requiring a significant amount of energy to be used, this can result in reducing the oxidised form of electron donors. For example, NAD+ can be reduced to NADH by complex I. There are several factors that have been shown to induce reverse electron flow. However, more work needs to be done to confirm this.
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Ronalds’ doctoral research was in the field of agricultural and physiological chemistry. Analysing wax by oxidation he created succinic acid, and published the results in Liebig's journal. He discovered taurine in human bile, which was announced in the Chemical Gazette (1846). That same year his important paper on urine was read to the Royal Society: he found that urine contained sulphur and phosphorus in both unoxidised and oxidised states and quantified the amounts.
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It is a secondary mineral found in the oxidised zones of copper ore deposits. Associated with libethenite at several localities in New South Wales, Australia,The Australian Journal of Mineralogy 3:50, 10:55, 10:79, 11:97 and 11:117 to 118 and at the Chino Mine, New Mexico, US.Rocks & Minerals (2009) 84:6 page 498 Other associated minerals are apatite, azurite, chalcedony, chrysocolla, cornetite, cuprite, malachite, pyromorphite, tenorite, and iron oxyhydroxides.
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Historically the prefixes “hypo-”, “per-”, “ortho-”, “meta-”, and “pyro-” were used to distinguish between different oxyacids of the same element, of these ortho acid is the most highly oxidised or hydroxylated. For example dehydration of orthoperiodic acid gives metaperiodic acid. Such naming conventions are now obsolete, however various traditional names containing these prefixes have been retained in IUPAC nomenclature (e.g. orthosilicic acid (Si(OH)4), orthotelluric acid (Te(OH)6) and orthophosphoric acid (PO(OH3)).
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The second stage used the same hypergolic propellants, whilst the third stage was the new Cryogenic Upper Stage (CUS), burning liquid hydrogen oxidised by liquid oxygen. The rocket's first and second stages performed normally, and at the time controllers reported that third stage ignition had occurred. However, shortly afterwards the rocket began to under-perform, tumbling out of control, and deviating from its planned trajectory. Around 300 seconds into the flight, contact with the rocket was lost.
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Although dichlorine is a strong oxidising agent with a high first ionisation energy, it may be oxidised under extreme conditions to form the cation. This is very unstable and has only been characterised by its electronic band spectrum when produced in a low-pressure discharge tube. The yellow cation is more stable and may be produced as follows:Greenwood and Earnshaw, pp. 842–44 :Cl2 \+ ClF + AsF5 This reaction is conducted in the oxidising solvent arsenic pentafluoride.
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DMS is oxidised in the atmosphere to form sulfur dioxide, and this leads to the production of sulfate aerosols. These aerosols act as cloud condensation nuclei and increase cloud droplet number, which in turn elevate the liquid water content of clouds and cloud area. This acts to increase cloud albedo, leading to greater reflection of incident sunlight, and a decrease in the forcing that initiated this chain of events. The figure to the right shows a summarising schematic diagram.
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The development of atherosclerosis is a complex process, though the main underlying feature is simply an increase in low-density lipoprotein (LDL) oxidation. PON1 and PON3 prevent the formation of atherogenic oxidised-LDL, the form of LDL present in foam cells of an atheromatous plaque. Because of their know association with high-density lipoprotein (HDL) and their effect on oxidized-LDL, PON1 and PON3 are implicated in lowering the risk of developing coronary artery disease and atherosclerosis.
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Chromatograms showing the oxidation of a proanthocyanidin B2 dimer. New peaks have appeared in the oxidised sample. Natural phenols are reactive species toward oxidation, notably the complex mixture of phenolics, found in food for example, can undergo autoxidation during the ageing process. Simple natural phenols can lead to the formation of B-type procyanidins in wines"Tandem mass spectrometry of the B-type procyanidins in wine and B-type dehydrodicatechins in an autoxidation mixture of (+)-catechin and (−)-epicatechin".
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Derivatised proteins: If [Ru(NH3)5]3+ is attached to certain histidine residues in a myoglobin protein, myoglobin is no longer a passive oxygen carrier, but gains enzymatic activity of an oxidase. Ascorbic acid is oxidised with molecular oxygen. Antibodies can act as enzymes, then named abzymes, if they are selected against transition state analogues. Abzymes have a low KM, meaning that they readily bind a target molecule, but have low Vmax values, indicating a slow reaction rate.
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Sulfur aerosols, especially stratospheric sulfur aerosols have a significant effect on climate. One source of such aerosols is the sulfur cycle, where plankton release gases such as DMS which eventually becomes oxidised to sulfur dioxide in the atmosphere. Disruption to the oceans as a result of ocean acidification or disruptions to the thermohaline circulation may result in disruption of the sulfur cycle, thus reducing its cooling effect on the planet through the creation of stratospheric sulfur aerosols.
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Particle moving from the work-piece to the cathode 5\. Surface before polishing 6\. Surface after polishing Typically, the work-piece is immersed in a temperature-controlled bath of electrolyte and serves as the anode; it is connected to the positive terminal of a DC power supply, the negative terminal being attached to the cathode. A current passes from the anode, where metal on the surface is oxidised and dissolved in the electrolyte, to the cathode.
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Oriel Sea Salt was established at Port Oriel, Clogherhead in 2010 by Brian Fitzpatrick and John Delany. It extracts and harvests salt and minerals from Irish Sea seawater. It describes itself as "the only non-oxidised sea salt on the planet": the seawater is pumped from the seabed without being exposed to air, resulting in a naturally white salt with a fine powdery grain and a "smooth depth of flavour." They received Protected designation of origin in 2016.
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Aira Caldera was created 22,000 years ago after a large scale of pyroclastic surges. The eruption of the Caldera assisted in its formation creating its total area of 17 x 23km. The formation of Aira Caldera started with a Plinian Pumice Eruption and was quickly followed by an oxidised Tsumaya pyroclastic flow (Aramaki, S. 1984). Basement rock fragments and pumiceous materials from a violent explosion formed the Ito pyroclastic flow about 300km3 in volume (Aramaki, S. 1984).
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A slowly oxidised plug of metallic uranium can sometimes resemble an onion subjected to desquamation. The main hazard however arises from the pyrophoric character of actinide metals which can spontaneously ignite when their specific area is high. This property, along with these elements inherent toxicity and (for some to a lesser extent) radioactivity, make them dangerous to handle in metallic form under air. Therefore, they are often handled under an inert atmosphere (nitrogen or argon) inside an anaerobic glovebox.
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The oxidation potential (Eh, measured in volts) is, as in any reaction system, the thermodynamic driving force of anaerobic respiration, which takes place in oxygen depleted environments. Prokaryotes are among the cells that have anaerobic respiration as metabolic strategy for survival. The electron transport takes place along and across the cellular membrane (prokaryotes lack of mitochondria). Electrons are transferred from an electron donor (molecule to be oxidised anaerobically) to an electron acceptor (NO3, SO4, MnO4, etc.).
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When ozone is bubbled through a slurry of americium(III) hydroxide in 0.03 M potassium bicarbonate at 92 °C, hexagonal KAmO2CO3 (potassium dioxoamericium(V) carbonate) can be obtained. Potassium carbonate can also be used. The resulting KAmO2CO3 reacts with dilute acids to produce americium dioxide. O3 \+ Am(OH)3 \+ KHCO3 \+ H2O → KAmO2CO3 \+ 3H2O + O2 In a dilute base such as sodium hypochlorite, Am(OH)3 gets oxidised to Am(OH)4, which is black in solution.
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Thus colour dye is formed at the site of development in each of the three layers of the film. Each layer of the film contains different couplers, which react with the same oxidised developer molecules but form different colour dyes. Next, the film goes into the pre- bleach (formerly conditioner) bath, which has a precursor of formaldehyde (as a dye preservative) and EDTA to "kick off" the bleach. Next, the film goes into a bleach solution.
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La Lucha de los Mineros Contra la Leyes: Chuquicamata (1900-1915) Luis Orellana Retamales The modern era started when the American engineer Bradley finally developed a method of working low grade oxidised copper ores. In 1910 he approached the lawyer and industrialist Albert C Burrage who sent engineers to examine Chuquicamata. Their reports were good and in April 1911 he started to buy up mines and claims in association with Duncan Fox y Cia., an English entrepreneur.
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Boyd also experimented with an electrolytic deposition of silver combined with a layer of copper, but abandoned that after finding that applying heated carbon tetrachloride to dissolve the wax from the metal shell was affecting his health. Boyd discontinued the electroplating with powdered granite compound infill described above in 1966, and the majority of his mature work is fine-face bronze casts using the lost wax process, in which he innovated through the admixture of silicon with wax, with editions of usually six produced in bronze and aluminium. Often a thin finish in silver is applied over the bronze or aluminium cast, oxidised to near-black then burnished lightly to reveal texture in relief; his 1971 Aboriginal Legend of Flight, commissioned for Sydney Kingsford Smith International Airport arrivals gate, after an earlier version (1969) for Tullamarine Airport, is an example. It is five and a half metres in width, modelled in clay, cast in plaster and then sand-cast in aluminium in 27 sections, coated in sterling silver over nickel and copper layers, then oxidised before being bolted together and the joins concealed.
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Exhaled air also passes through the respirator mouthpiece and an exhaust valve, but not the catalyst, as damp exhaled air would affect its efficiency. Respirators may provide a heat exchanger to carry away some of their heat in this exhaled air. These respirators are not designed to protect against toxic gases other than carbon monoxide. They may have some ability to reduce it, especially if it will be oxidised safely by the catalyst (such as ozone), but this is incidental.
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Erosion of the then recently uplifted landmass formed Aeolian deposits in the southern and central parts of the country. This iron-rich silica sandstone was both oxidised and reworked to give it its red colouration and its name, "New Red Sandstone". British deposits of the era consist of these red beds, alluvial, fluvial and lake deposits, with some shallow-water marine and evaporite deposits. These Permo-Triassic outcrops can be seen on either side of the Pennines and in Devon.
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Sulfur is input into the clinker burning process via raw materials and fuels. Depending on their origin, the raw materials may contain sulfur bound as sulfide or sulfate. Higher SO2 emissions by rotary kiln systems in the cement industry are often attributable to the sulfides contained in the raw material, which become oxidised to form SO2 at the temperatures between 370 °C and 420 °C prevailing in the kiln preheater. Most of the sulfides are pyrite or marcasite contained in the raw materials.
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Kurup's initial idea that won her the Discovery Education 3M Young Scientist in 2012 is based on using a photocatalytic compound for water purification. This project involved a photocatalytic composite made up of titanium dioxide and zinc oxide, hollow glass microspheres, and Portland cement. In 2012 Kurup's photocatalytic composite was able to reduce the amount of total coliform from 8000 colony- forming units to 50. In addition, it oxidised Methylene blue at a faster rate than standard solar disinfection methods.
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Rufous () is a colour that may be described as reddish-brown or brownish-red, as of rust or oxidised iron. The first recorded use of rufous as a colour name in English was in 1782.Maerz and Paul A Dictionary of Color New York:1930 McGraw-Hill Page 203; Color Sample of Rufous: Page 45 Plate 10 Color Sample A10 However, the colour is also recorded earlier in 1527 as a diagnostic urine colour.Anon., Here begineth the seinge of urynes.
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The white phosphorus is then oxidised to phosphoric acid and subsequently neutralised with base to give phosphate salts. Phosphoric acid produced from white phosphorus is relatively pure and is the main route for the production of phosphates for all purposes, including detergent production. In the early 1990s, Albright and Wilson's purified wet phosphoric acid business was being adversely affected by phosphate rock sales by China and the entry of their long-standing Moroccan phosphate suppliers into the purified wet phosphoric acid business.
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Electrochemical experiments show that (+)-catechin oxidation mechanism proceeds in sequential steps, related with the catechol and resorcinol groups and the oxidation is pH-dependent. The oxidation of the catechol 3',4'-dihydroxyl electron-donating groups occurs first, at very low positive potentials, and is a reversible reaction. The hydroxyl groups of the resorcinol moiety oxidised afterwards were shown to undergo an irreversible oxidation reaction. The laccase/ABTS system oxidizes (+)-catechin to oligomeric products of which proanthocyanidin A2 is a dimer.
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15N tracing allows researchers to distinguish specific nitrogen conversions from a network of simultaneous reactions; e.g. ammonium can at the same time be oxidised by autotrophic microorganisms, produced by mineralisation of organic matter, produced by dissimilatory nitrate reduction and assimilated by microbes and plants. In this case, quantifying the absolute amounts of ammonium does not explain how it is produced or consumed. However, the conversion of one 15N labelled compound to another can directly be linked through the isotopic signature.
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LDL contains apolipoprotein B (apoB), which allows LDL to bind to different tissues, such as the artery wall if the glycocalyx has been damaged by high blood sugar levels. If oxidised, the LDL can become trapped in the proteoglycans, preventing its removal by HDL cholesterol efflux. Normal functioning HDL is able to prevent the process of oxidation of LDL and the subsequent inflammatory processes seen after oxidation. Lipopolysaccharide, or LPS, is the major pathogenic factor on the cell wall of Gram-negative bacteria.
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The nitric acid process produces nitric acid for use in making ammonium nitrate fertiliser. Using the Ostwald process, ammonia is vaporised and then oxidised over a 95% platinum and 5% rhodium catalyst at and to form nitric oxide and superheated steam. The reaction gases are cooled to before absorption by various heat recovery mechanisms. The cooled reaction gases are then passed through the bottom of an absorption column where a stream of air is added to oxidise nitric oxide to nitrogen dioxide.
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The workshop/storeroom area was completed and an ablution block was adapted from concrete engine beds remaining from previous operations. Mullock, soil and oxidised material were spread over much of the site during this time to provide a safer working surface. Mullock was also spread out between the main shaft and river, covering the Daintree shaft mouth. In February 1971 the steel tripod was put over the main shaft, and in March a tramway was installed between the main shaft and the river bank.
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Isoleucine is both a glucogenic and a ketogenic amino acid. After transamination with alpha-ketoglutarate the carbon skeleton is oxidised and split into propionyl-CoA and acetyl-CoA. Propionyl- CoA is converted into succinyl-CoA, a TCA cycle intermediate which can be converted into oxaloacetate for gluconeogenesis (hence glucogenic). In mammals acetyl-CoA cannot be converted to carbohydrate but can be either fed into the TCA cycle by condensing with oxaloacetate to form citrate or used in the synthesis of ketone bodies (hence ketogenic) or fatty acids.
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Working temperatures for threadlocked fasteners are typically limited to 150°C (300°F), which is below the softening point of the methacrylate polymer. Above this temperature, the material softens and strength reduces. Because thread locking adhesives typically rely on the electrochemical activity of a metal substrate to form a bond, surfaces must be clean to develop the full bonding strength. In the case of less electrochemically active metals such as the normally oxidised surface of aluminium, an additional step of priming is required for full strength results.
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It occurs as small prismatic or pyramidal crystals, usually forming drusy crusts and stalactitic aggregates; also as fibrous encrusting masses with a mammillary surface. Descloizite occurs in oxidised portions of veins of lead ores in association with pyromorphite, vanadinite, wulfenite, mottramite, mimetite and cerussite. The Otavi ("O-tarvi") Mountainland of northern Namibia was once considered home to the greatest vanadium deposits in the world, including those at Berg Aukas ("OW- cuss"), Abenab ("UB-en-ub"), Baltika ("BUL-tika") and Uitsab ("ATE-sub").Boni et al.
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The pnictogen hydrides become denser down the group and the M–H bond lengths increase, while the H–M–H bond angle decreases slightly. The standard enthalpies of formation reflect the increasing thermal instability going down the group. Arsine decomposes to arsenic and hydrogen at 250–300 °C, stibine to antimony and hydrogen at room temperature, and bismuthine to bismuth and hydrogen above −45 °C. Arsine and stibine are very easily oxidised to arsenic or antimony trioxide and water; a similar reaction happens with sulfur or selenium.
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When fresh the rocks have a greenish colouration owing to the presence of glauconite, but on exposure to the atmosphere this is rapidly oxidised to limonite, giving rise to a yellow or reddish brown staining.Gallois (1965), p.30. The Lower Greensand is composed of alternating mudstones (sandy, with clay particles such as smectite) and sandstones, up to a maximum thickness of about , and is composed of a number of distinct formations, namely the Folkestone Beds, Sandgate Beds, Bargate Beds, Hythe Beds and Atherfield Clay.Gallois (1965), p.4.
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The achiral meso compound (1R,2S)-1,2-diphenyloxirane arises from cis-stilbene, though peroxide epoxidations of the cis-isomer produce both cis- and trans-epoxide products. For example, using tert-butyl hydroperoxide, oxidation of cis-stilbene produces 0.8% cis-stilbene oxide, 13.5% trans-stilbene oxide, and 6.1% benzaldehyde. Enantiopure stilbene oxide has been prepared by Nobel laureate Karl Barry Sharpless. :500px Stilbene can be cleanly oxidised to benzaldehyde by ozonolysis or Lemieux–Johnson oxidation, and stronger oxidants such as acidified potassium permanganate will produce benzoic acid.
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Between 2009 and 2013, a freestanding 24sqm studio was added. It is designed in dialog with but also in opposition to the original house; as stated on Godsell's website, they are 'connected by their common materiality of oxidised steel and recycled hardwood flooring, but are physically separate', and is ' deliberately solid and dark in comparison to the light filled and screened earlier house', and 'vertical, where the existing house is horizontal.' The addition won the 2014 National Award for Small Projects from the Australian Institute of Architects.
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The Carius halogen method in analytical chemistry is a method for the quantitative determination of halogens in chemical substances.Julius B. Cohen Practical Organic Chemistry 1910 Link to online text A known mass of an organic compound is heated with fuming nitric acid in the presence of silver nitrate contained in a hard glass tube known as carius tube, in a furnace. Carbon and hydrogen present in the compound are oxidised to carbon dioxide and water. The halogen present forms the corresponding silver halide (AgX).
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Inosine is a nucleoside that is formed when hypoxanthine is attached to a ribose ring (also known as a ribofuranose) via a β-N9-glycosidic bond. Inosine is commonly found in tRNAs and is essential for proper translation of the genetic code in wobble base pairs. Wobble base pairs for inosine and guanine Knowledge of inosine metabolism has led to advances in immunotherapy in recent decades. Inosine monophosphate is oxidised by the enzyme inosine monophosphate dehydrogenase, yielding xanthosine monophosphate, a key precursor in purine metabolism.
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By monitoring the amount of arsenic at various positions downstream, Hering found that the concentration remained constant, but the oxidation state changed. Hering found that arsenic was being oxidised into Arsenic(V) by a biological agent known as a macrophyte. She monitored Owens Lake, which is once of the largest in California but has dried up since the Los Angeles Aqueduct was constructed. The dusty lake bed results in large (> 10 μm) particles of high arsenic content airborne dust that can travel far and be inhaled.
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Rhodocene is ca. 500 mV more reducing than cobaltocene, indicating that it is more readily oxidised and hence less stable. An earlier polarographic investigation of rhodocenium perchlorate at neutral pH showed a cathodic wave peak at −1.53 V (versus SCE) at the dropping mercury electrode, corresponding to the formation rhodocene in solution, but the researchers were unable to isolate the neutral product from solution. In the same study, attempts to detect iridocene by exposing iridocenium salts to oxidising conditions were unsuccessful even at elevated pH.
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The organic matter is vaporised by heating and nature and position of mineral ash is determined microscopically. Aqueous or cryo-EM fixed tissue materials can also be examined under transmission and scanning electron microscopy (TEM & SEM). The ashing procedure produces cellular oxidised-residues rich in Na2O, CaO, MgO, Fe2O3, SiO2, Ca(PO4)2, Mg(PO4)2, etc., which are detected by X-ray microanalysis with 2-4 times sensitivity gained after incineration of sample, due to increased mineral concentration and reduced nonspecific background radiation.
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They are now quite common in the Languedoc- Roussillon of southwest France. As the names suggest, Muscat de Beaumes-de- Venise, Muscat de Rivesaltes, Muscat de Frontignan, Muscat de Lunel, Muscat de Mireval and Muscat de St-Jean Minervois are all made from the white Muscat grape, whilst Banyuls and Maury are made from red Grenache. Regardless of the grape, fermentation is stopped with up to 10% of 95% grape spirit. The Muscats are made in a somewhat oxidised style, the Grenaches less so.
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In N,N-dialkylhydrazones the C=N bond can be hydrolysed, oxidised and reduced, the N-N bond can be reduced to the free amine. The carbon atom of the C=N bond can react with organometallic nucleophiles. The alpha-hydrogen atom is more acidic by 10 orders of magnitude compared to the ketone and therefore more nucleophilic. Deprotonation with for instance LDA gives an azaenolate which can be alkylated by alkyl halides, a reaction pioneered by Elias James Corey and Dieter Enders in 1978.
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The town is situated on an ancient geological feature known as the Hartbeesfontein basin (or KOSH basin), which is the source of the gold found on its southern rim. Underground water occurs in abundance in dolomitic aquifers of the region. When the water is however allowed to seep into mines it is oxidised and polluted by the exposed iron pyrites. As of 2005 when Buffelsfontein mine went out of business, it became a burden on the remaining mines to keep the interconnected tunnels free of water.
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Hydrazine can be synthesized from ammonia and hydrogen peroxide in the Peroxide process (sometimes called Pechiney-Ugine-Kuhlmann process, the Atofina–PCUK cycle, or ketazine process). The net reaction follows: :2NH3 + H2O2 -> H2NNH2 + 2H2O In this route, the ketone and ammonia first condense to give the imine, which is oxidised by hydrogen peroxide to the oxaziridine, a three-membered ring containing carbon, oxygen, and nitrogen. Next, the oxaziridine gives the hydrazone by treatment with ammonia, which process creates the nitrogen-nitrogen single bond. This hydrazone condenses with one more equivalent of ketone.
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Zinc(II) hydride slowly decomposes to metallic zinc and H2 at room temperature, with decomposition becoming rapid if it is heated above 90°C. :ZnH2 → H2 \+ Zn0 It is readily oxidised and is sensitive to both air and moisture; being hydrolysed slowly by water but violently by aqueous acids, which indicates possible passivation via the formation of a surface layer of ZnO. Despite this older samples may be pyrophoric. Zinc hydride can therefore be considered metastable at best, however it is still the most stable of all the binary first row transition metal hydrides (c.f.
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The event resulted in the supersaturated deep water rapidly mixing with the upper layers of the lake, where the reduced pressure allowed the stored CO2 to effervesce out of solution. It is believed that about of gas was released. The normally blue waters of the lake turned a deep red after the outgassing, due to iron-rich water from the deep rising to the surface and being oxidised by the air. The level of the lake dropped by about a metre and trees near the lake were knocked down.
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The Kelabit Highlands is thought to developed from the rifted continental crust where water sediments were deposited before Borneo was separated from the mainland Eurasian plate. This is evidenced by the presence of evaporite and limestone found in the area. Evidence of folding and faulting along the NE-SW axis is also found in this area. The types of stones changes from oxidised iron and coal-bearing sandstones in the east of Kelabit highlands, to mudstone and limestone of the Kelabit highlands, and grey sandsones westwards in the Mount Murud region.
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The development of an economic ultrafine grinding technology has made possible atmospheric leaching of minerals for which this was previously impossible. MIM Holdings also developed, through its research facility located in Albion, a suburb of Brisbane, an atmospheric leaching process called the Albion Process. By using IsaMills to grind the particles of refractory minerals to ultrafine sizes, the Albion Process increases the activity of sulfide concentrates to the point where they can be readily oxidised in conventional open tanks. Thus, the oxidation is carried out without the need for high pressure, expensive reagents or bacteria.
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This formation is thick and is composed of carbonate-silicate iron formations and associated manganese oxide deposits. The iron oxidised to form hematite and goethite. The uppermost Rabbit Lake Formation has a lower member of black mudstone inserted with beds of iron formation and units of volcanogenic origin; and an upper member of slate, carbonaceous mudstone, greywacke and thin units of iron-rich strata. Syncline and anticlines The top sedimentary layer is the Thomson Formation which was deposited 1,880 to 1,870 million years ago and deformed by the Penokean orogeny 1,850 million years ago.
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The sealing is necessary to stop the CO either leaking out or being oxidised to CO2 by excess outside air. Adding an easily decomposed carbonate "energiser" such as barium carbonate breaks down to BaO + CO2 and this encourages the reaction :C (from the donor) + CO2 <—> 2 CO increasing the overall abundance of CO and the activity of the carburising compound. It is a common knowledge fallacy that case-hardening was done with bone but this is misleading. Although bone was used, the main carbon donor was hoof and horn.
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The second half of glycolysis is known as the pay-off phase, characterised by a net gain of the energy-rich molecules ATP and NADH. Since glucose leads to two triose sugars in the preparatory phase, each reaction in the pay-off phase occurs twice per glucose molecule. This yields 2 NADH molecules and 4 ATP molecules, leading to a net gain of 2 NADH molecules and 2 ATP molecules from the glycolytic pathway per glucose. The aldehyde groups of the triose sugars are oxidised, and inorganic phosphate is added to them, forming 1,3-bisphosphoglycerate.
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Chlorophyllide-a oxygenase (), chlorophyllide a oxygenase, chlorophyll-b synthase, CAO) is an enzyme with systematic name chlorophyllide-a:oxygen 7-oxidoreductase. This enzyme catalyses the following chemical reactions : (1) chlorophyllide a + O2 \+ NADPH + H+ \rightleftharpoons 7-hydroxychlorophyllide a + H2O + NADP+ : (2) 7-hydroxychlorophyllide a + O2 \+ NADPH + H+ \rightleftharpoons chlorophyllide b + 2 H2O + NADP+ Chlorophyllide a, (R=H) is converted to chlorophyllide b, in which the methyl group show in the green box is oxidised to a formyl group. This enzyme contains a mononuclear iron centre and is part of the biosynthetic pathway to chlorophylls.
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This is known as regeneration, since the ammonium can be used by phytoplankton, and again enter the food-web. Primary production fuelled by ammonium in this way is thus referred to as regenerated production. However, ammonium can also be oxidised to nitrate (via nitrite), by the process of nitrification. This is performed by different bacteria in two stages : :::NH3 \+ O2 → NO2− \+ 3H+ \+ 2e− :::NO2− \+ H2O → NO3− \+ 2H+ \+ 2e− Crucially, this process is believed to only occur in the absence of light (or as some other function of depth).
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Oxidation is usually relatively easy to detect, owing to the strong absorption by the carbonyl group in the spectrum of polyolefins. Polypropylene has a relatively simple spectrum, with few peaks at the carbonyl position (like polyethylene). Oxidation tends to start at tertiary carbon atoms because free radicals here are more stable, so last longer and are attacked by oxygen. The carbonyl group can be further oxidised to break the chain, so weakening the material by lowering the molecular weight, and cracks start to grow in the regions affected.
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To achieve more than one colour on a given vase, a further trick is necessary: The black magnetite Fe3O4 has to be prevented from returning to matt red hematite Fe2O3. In other words, the areas to remain black have to be denied access to oxygen, their oxidised particles must be "sealed". This is achieved by using a further property of the clay: the vitrification point, i.e. the temperature at which the individual clay particles irreversibly merge, depends on the composition of the clay and on the particles contained in it.
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This is known as regeneration, since the ammonium can be used by phytoplankton, and again enter the food-web. Primary production fuelled by ammonium in this way is thus referred to as regenerated production. However, ammonium can also be oxidised to nitrate (via nitrite), by the process of nitrification. This is performed by different bacteria in two stages : NH3 \+ O2 → NO2− \+ 3H+ \+ 2e− NO2− \+ H2O → NO3− \+ 2H+ \+ 2e− Crucially, this process is believed to only occur in the absence of light (or as some other function of depth).
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Copper(II) chloride is prepared commercially by the action of chlorination of copper. Copper at red heat (300-400°C) combines directly with chlorine gas, giving (molten) copper (II) chloride. The reaction is very exothermic. : Cu(s) + Cl2(g) → CuCl2(l) It is also commercially practical to combine copper(II) oxide with an excess of ammonium chloride at similar temperatures, producing copper chloride, ammonia, and water: : CuO + 2NH4Cl → CuCl2 \+ 2NH3 \+ H2O Although copper metal itself cannot be oxidised by hydrochloric acid, copper- containing bases such as the hydroxide, oxide, or copper(II) carbonate can be.
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In solution, the ferrioxalate complex undergoes photoreduction. In this process, the complex absorbs a photon of light and subsequently decomposes to form and . The iron centre is reduced (gains an electron) from the +3 to the +2 oxidation state, while an oxalate ion is oxidised to carbon dioxide: : 2 []3− \+ hν → 2 []2− \+ 2 + This reaction provides an efficient chemical method for photometry and actinometry, the measurement of light and higher-energy electromagnetic radiation. Potassium ferrioxalate is over 1000 times more sensitive than uranyl oxalate, the compound previously used for these purposes.
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Luminescent bacteria emit light as the result of a chemical reaction during which chemical energy is converted to light energy. Luminescent bacteria exist as symbiotic organisms carried within a larger organism, such as many deep sea organisms, including the Lantern Fish, the Angler fish, certain jellyfish, certain clams and the Gulper eel. The light is generated by an enzyme- catalyzed chemoluminescence reaction, wherein the pigment luciferin is oxidised by the enzyme luciferase. The expression of genes related to bioluminescence is controlled by an operon called the lux operon.
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Sb2S3 can be prepared from the elements at temperature 500-900 °C: :2Sb + 3S → Sb2S3 Sb2S3 is precipitated when H2S is passed through an acidified solution of Sb(III). This reaction has been used as a gravimetric method for determining antimony, bubbling H2S through a solution of Sb(III) compound in hot HCl deposits an orange form of Sb2S3 which turns black under the reaction conditions.A.I. Vogel, (1951), Quantitative Inorganic analysis, (2d edition), Longmans Green and Co Sb2S3 is readily oxidised, reacting vigorously with oxidising agents. It burns in air with a blue flame.
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Cyclic heme is oxidised to linear biliverdin IXα by heme oxygenase and further converted to 3Z-phycocyanobilin, the dominant phycocyanobilin isomer, by 3Z-phycocyanobilin:ferredoxin oxidoreductase. Insertion of 3Z-phycocyanobilin into the C-PC apo-protein via thioether bond formation is catalysed by phycocyanobilin lyase. The promoter for the cpc operon is located within the 427-bp upstream region of the cpcB gene. In A. platensis, 6 putative promoter sequences have been identified in the region, with four of them showing expression of green fluorescent protein when transformed into E. coli.
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Superheated water, along with supercritical water, has been used to oxidise hazardous material in the wet oxidation process. Organic compounds are rapidly oxidised without the production of toxic materials sometimes produced by combustion. However, when the oxygen levels are lower, organic compounds can be quite stable in superheated water. As the concentration of hydronium () and hydroxide () ions are 100 times larger than in water at 25 °C, superheated water can act as a stronger acid and a stronger base, and many different types of reaction can be carried out.
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Oxidation is usually relatively easy to detect owing to the strong absorption by the carbonyl group in the spectrum of polyolefins. Polypropylene has a relatively simple spectrum with few peaks at the carbonyl position (like polyethylene). Oxidation tends to start at tertiary carbon atoms because the free radicals formed here are more stable and longer lasting, making them more susceptible to attack by oxygen. The carbonyl group can be further oxidised to break the chain, this weakens the material by lowering its molecular weight, and cracks start to grow in the regions affected.
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The roasting process is generally undertaken in combination with reverberatory furnaces. In the roaster, the copper concentrate is partially oxidised to produce "calcine" and sulfur dioxide gas. The stoichiometry of the reaction which occurs is: :2 CuFeS2 \+ 3 O2 → 2 FeO + 2 CuS + 2 SO2 Roasting generally leaves more sulfur in the calcined product (15% in the case of the roaster at Mount Isa MinesB V Borgelt, G E Casley and J Pritchard (1974) "Fluid bed roasting at Mount Isa," The Aus.I.M.M. North West Queensland Branch, Regional Meeting, August 1974.
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Esophagitis or gastritis, for example, may bleed and produce coffee-ground vomitus. When unaccompanied by melena, hematemesis or a fall in hemoglobin with corresponding urea rises and creates an unstable reaction, and other causes of coffee ground vomitus need to be elucidated; for example, gastric stasis, bowel obstruction or ileus, that can cause oxidised food material to be vomited. Vomiting iron supplements can also mimic coffee grounds to the untrained eye. When attributed to peptic inflammation, use of nonsteroidal anti-inflammatory drugs (NSAIDs) and selective serotonin reuptake inhibitors (SSRIs) are commonly implicated.
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There are several possible explanations for this difference, of which the most likely one given is the hypothesis that the temperature is evenly distributed enough that soot is not formed and complete combustion occurs., National Aeronautics and Space Administration, April 2005. Experiments by NASA in microgravity reveal that diffusion flames in microgravity allow more soot to be completely oxidised after they are produced than diffusion flames on Earth, because of a series of mechanisms that behaved differently in microgravity when compared to normal gravity conditions.LSP-1 experiment results, National Aeronautics and Space Administration, April 2005.
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A primary size-limiting factor is the amount of atmospheric oxygen. Without a complex circulatory system, low concentrations of oxygen cannot reach the centre of an organism quickly enough to supply its metabolic demand. On the early Earth, reactive elements, such as iron and uranium, existed in a reduced form that would react with any free oxygen produced by photosynthesising organisms. Oxygen would not be able to build up in the atmosphere until all the iron had rusted (producing banded iron formations), and all the other reactive elements had been oxidised.
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Another view of the memorial The chemical works, owned by Nypro UK (a joint venture between Dutch State Mines (DSM) and the British National Coal Board (NCB)) had originally produced fertiliser from by- products of the coke ovens of a nearby steelworks. Since 1967, it had instead produced caprolactam, a chemical used in the manufacture of nylon 6. The caprolactam was produced from cyclohexanone. This was originally produced by hydrogenation of phenol, but in 1972 additional capacity was added, built to a DSM design in which hot liquid cyclohexane was partially oxidised by compressed air.
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It is one of the three most used acids (the other two being sulfuric acid and hydrochloric acid) and was first discovered by the alchemists in the 13th century. It is made by catalytic oxidation of ammonia to nitric oxide, which is oxidised to nitrogen dioxide, and then dissolved in water to give concentrated nitric acid. In the United States of America, over seven million tonnes of nitric acid are produced every year, most of which is used for nitrate production for fertilisers and explosives, among other uses.
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Whatever the cause, the event resulted in the rapid mixing of the supersaturated deep water with the upper layers of the lake, where the reduced pressure allowed the stored to effervesce out of solution. It is believed that about of gas was released. The normally blue waters of the lake turned a deep red after the outgassing, due to iron-rich water from the deep rising to the surface and being oxidised by the air. The level of the lake dropped by about a metre and trees near the lake were knocked down.
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The Bungle Bungle Range, lying fully within the park, has elevations as high as above sea level. It is famous for the sandstone domes, unusual and visually striking with their striping in alternating orange and grey bands. The banding of the domes is due to differences in clay content and porosity of the sandstone layers: the orange bands consist of oxidised iron compounds in layers that dry out too quickly for cyanobacteria to multiply; the grey bands are composed of cyanobacteria growing on the surface of layers of sandstone where moisture accumulates.
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Cellular respiration is the process by which biological fuels are oxidised in the presence of a high-energy inorganic electron acceptor (such as oxygen) to produce large amounts of energy, to drive the bulk production of ATP. Anaerobic respiration is used by some microorganisms in which neither oxygen (aerobic respiration) nor pyruvate derivatives (fermentation) is the high-energy final electron acceptor. Rather, an inorganic acceptor such as sulfate or nitrate is used. Such organisms are typically found in unusual places such as underwater caves or near hydrothermal vents at the bottom of the ocean.
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The ate complex undergoes a 1,2-metallate rearrangement to give the homologated product, which is then further oxidised to a secondary alcohol.Iterative Stereospecific Reagent-Controlled Homologation of Pinacol Boronates by Enantioenriched -Chloroalkyllithium Reagents Paul R. Blakemore and Matthew S. Burge J. Am. Chem. Soc.; 2007; 129(11) pp 3068 - 3069; (Communication) :Insertion of carbenoid into C-B bond The enantiopurity of the chiral sulfoxide is preserved in the ultimate product after oxidation of the boronic ester to the alcohol indicating that a true carbene was never involved in the sequence.
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Dr. Gurpreet Singh Wander has published 120 papers, 45 of them in foreign journals of repute like The Lancet, Nature, Journal of Genetics, Journal of American College of Cardiology, American Journal of Cardiology, British Heart Journal and Japanese Heart Journal. He has presented 115 papers at national and international conferences. He had conducted few animal experiment studies on atherogenicity of oxidised cholesterol and a British collaborative study on Coronary Heart Disease. He has been co-supervisor of post-graduation MD/MS thesis for Punjab University, Chandigarh and Baba Farid University, Faridkot, Punjab.
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Kits for a quality repair are available that allow the lens to be polished with progressively finer abrasives, and then be sprayed with an aerosol of ultra violet resistant clear coating. The reflector, made out of vaporized aluminum deposited in an extremely thin layer on a metal, glass or plastic substrate, can become dirty, oxidised, or burnt, and lose its specularity. This can happen if water enters the headlamp, if bulbs of higher than specified wattage are installed, or simply with age and use. Reflectors thus degraded, if they cannot be cleaned, must be replaced.
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It refers to the major changes that culminated in the Firefox 57 release with the Quantum project. "Time and Space" refer to Quantum itself, while "Flow" refers to the Quantum Flow project, "new raiment" and "Light" refer to the UI refresh known as the Photon project. The Quantum Project contained the first major piece of code taken from Servo, the layout engine written in Rust, to which "oxidised metal" is a reference. The 11:14 chapter and verse notation refers to November 14, 2017, the day Firefox 57 was released.
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Adipose tissue contains many small blood vessels. In the integumentary system, which includes the skin, it accumulates in the deepest level, the subcutaneous layer, providing insulation from heat and cold. Around organs, it provides protective padding. However, its main function is to be a reserve of lipids, which can be oxidised to meet the energy needs of the body and to protect it from excess glucose by storing triglycerides produced by the liver from sugars, although some evidence suggests that most lipid synthesis from carbohydrates occurs in the adipose tissue itself.
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HALS do not absorb UV radiation, but act to inhibit degradation of the polymer by continuously and cyclically removing free radicals that are produced by photo-oxidation of the polymer. The overall process is sometimes referred to as the Denisov cycle, after Evguenii T. Denisov and is exceedingly complex. Broadly, HALS react with the initial polymer peroxy radical (ROO•) and alkyl polymer radicals (R•) formed by the reaction of the polymer and oxygen, preventing further radical oxidation. By these reactions HALS are oxidised to their corresponding aminoxyl radicals (R2NO• c.f.
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An Anglo-Saxon burial dated to the early 7th century, known as Grave AX, was found located amidst the buildings at Yeavering. Hope- Taylor characterised it as "one of the strangest and most interesting minor features of the site" and it contained the diffuse outline of an adult body which had been interned in an east-west alignment. Various oxidised remnants of what were originally metal objects were found with the body, as was the remnants of a goat skull, which had been positioned to face eastward.Hope- Taylor 1977. p. 67-69.
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A methyl cobalt bond of the intermediary methyl carrier, methlycob(III)alamin is cleaved heterolytically producing cobalamin in its highly reactive oxidation state as cob(I)alamin. The enzyme bound cob(I)alamin cofactor of the MTR enzyme functions as a methyl carrier between 5-MTHF and homocysteine. Cob(I)alamin is oxidised to cob(II)alamin about once every 100 methyl transfer cycles, rendering the cob(I)alamin-MTR-enzyme complex inactive. Reactivation of this enzyme complex occurs through reductive remethylation by MTRR, utilizing S-adenosylmethionine as a methyl donor.
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The lower oxidation state of manganese (Mn2+) is yellow in common glass while the higher oxidation states (Mn3+ or higher) is purple. A combination of the two states will give a pink glass. As the manganese and iron may each be in different states of oxidation, the combination of the two can result in a broad range of attractive colours. Manganese in its fully oxidised state, if not present in too great a mass, will also act as a decolourant of glass if the iron is in its yellow, ferric form.
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In 1911 the Dumet-wire seal was invented which is still the common practice to seal copper leads through soda-lime or lead glass. If copper is properly oxidised before it is wetted by molten glass a vacuum tight seal of good mechanical strength can be obtained. After copper is oxidized, it is often dipped in a borax solution, as borating the copper helps prevents over-oxidation when reintroduced to a flame. Simple copper wire is not usable because its coefficient of thermal expansion is much higher than that of the glass.
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The latter, discovered at Ruvo di Puglia, is "almost identical" to that of Ksour Essef, "the differences [...] are insignificant", even if the latter is in a poorer state of conservation because it is strongly oxidised. The representation of Minerva can be compared to the representations of the same deity known for Campania between 317 and 211 according to the searcher. The belt also belongs to a type present in Southern Italy. The presence of such a breastplate in Tunisia very quickly prompted historians to link it to the Second Punic War.
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The river coursing out of the north of the site, a tributary of the River Par, was found to flow through tin-bearing gravels by the early mediaeval period. This part of Red Moor was mined for loose tin until the end of the 19th century and the oxidised metal is thought to give the moor its descriptive name. This SSSI used to belong to the Red Moor–Breney Common SSSI, the two sites having split in the 1986 revision where both sites were expanded. It is adjacent to Helman Tor nature reserve.
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In the early steps of the biosynthesis, which starts from glutamic acid, a tetrapyrrole is created by the enzymes deaminase and cosynthetase which transform aminolevulinic acid via porphobilinogen and hydroxymethylbilane to uroporphyrinogen III. The latter is the first macrocyclic intermediate common to haem, sirohaem, cofactor F430, cobalamin and chlorophyll itself. The next intermediates are coproporphyrinogen III and protoporphyrinogen IX, which is oxidised to the fully aromatic protoporphyrin IX. Insertion of iron into protoporphyrin IX in for example mammals gives haem, the oxygen-carrying cofactor in blood, but plants combine magnesium instead to give, after further transformations, chlorophyll for photosynthesis.
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Some producers will still use non-oak barrels, such as chestnut, juniper and cherry wood and may even blend batches of Vin Santo aged in different wood barrels together. This has the potential of giving the wines more layers of complexity in much the same way that vinegar producers in the Emilia-Romagna region use different wood types to add complexity to their vinegar. As a fall back, if their wines become too oxidised or do not develop the way the producer wishes, some Vin Santo may be intentionally converted into vinegar that is very desirable in the culinary market.
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This allows electro-ablation to break through highly resistive oxide surfaces, such as those found on Titanium and other exotic metals and alloys. Through software control, electro-ablation processes are able to quickly remove - via ablation - tough protective oxide layers and then immediately reduce the current flow to avoid melting the underlying non-oxidised metal or alloy. This allows very quick surface finishing. The process is capable of providing surface finishing for a wide range of exotic and widely used metals and alloys, including: Titanium, Stainless Steel, Niobium, Chromium-Cobalt, Inconel, Aluminium and a range of widely available steels and alloys.
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Under anaerobic conditions, the iron(II) hydroxide can be oxidised by the protons of water to form magnetite (iron(II,III) oxide) and molecular hydrogen. This process is described by the Schikorr reaction: :3 Fe(OH)2 → Fe3O4 \+ H2 \+ 2 H2O Anions such as selenite and selenate can be easily adsorbed on the positively charged surface of iron(II) hydroxide, where they are subsequently reduced by Fe2+. The resulting products are poorly soluble (Se0, FeSe, or FeSe2). Iron(II) hydroxide has also been investigated as an agent for the removal of toxic selenate and selenite ions from water systems such as wetlands.
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Chalcopyrite-rich ore specimen from Olympic Dam Chalcopyrite in hematised breccia from Prominent Hill Ore minerals in IOCG deposits are typically copper-iron sulfide chalcopyrite and gangue pyrite, forming 10–15% of the rock mass. Supergene profiles can be developed above weathered examples of IOCG deposits, as exemplified by the Sossego deposit, Para State, Brazil, where typical oxidised copper minerals are present, e.g.; malachite, cuprite, native copper and minor amounts of digenite and chalcocite. Alteration is a mixture of sodic-calcic (albite-epidote) to potassic (K-feldspar) in style, and may vary from province to province based on host rocks and mineralising processes.
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Supersonic nozzles enable oxygen jets to penetrate foaming slag and reach the liquid bath. An important part of steelmaking is the formation of slag, which floats on the surface of the molten steel. Slag usually consists of metal oxides, and acts as a destination for oxidised impurities, as a thermal blanket (stopping excessive heat loss) and helping to reduce erosion of the refractory lining. For a furnace with basic refractories, which includes most carbon steel-producing furnaces, the usual slag formers are calcium oxide (CaO, in the form of burnt lime) and magnesium oxide (MgO, in the form of dolomite and magnesite).
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The adsorbent, loaded with adsorbed pollutant on its surface sediments and forms a bed in the regeneration zone in the cell. The mass of the Nyex causes the bed to travel down the regeneration column slowly and eventually pass back into the cell. During the journey down the regeneration column, a DC current is passed across the electrochemical cell of which the adsorbent forms the anode. The applied current causes the pollutants adsorbed on the surface of the Nyex to be electrochemically oxidised regenerating the adsorbent surface restoring its full adsorptive capacity completing the adsorption-regeneration cycle.
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The older and relatively simple method of cupellation can then be used to separate the silver from the lead. If the lead is assayed and found not to contain enough silver to make the cupellation process worthwhile it is reused in liquation cakes until it has sufficient silver. The ‘exhausted liquation cakes’ which still contain some lead and silver are ‘dried’ in a special furnace which is heated to a higher temperature under oxidising conditions. This is essentially just another stage of liquation and most of the remaining lead is expelled and oxidised to form liquation thorns, though some remains as lead metal.
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Bond is a heavy smoker, at one point smoking 70 cigarettes a day. Bond has his cigarettes custom-made by Morland of Grosvenor Street, mixing Balkan and Turkish tobacco and having a higher nicotine content than normal; the cigarettes have three gold bands on the filter. Bond carried his cigarettes in a wide gunmetal cigarette case which carried fifty; he also used a black oxidised Ronson lighter. The cigarettes were the same as Fleming's, who had been buying his at Morland since the 1930s; the three gold bands on the filter were added during the war to mirror his naval Commander's rank.
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The plant was effective at removing sulphur compounds from the flue-gases (over its operational life it achieved an overall average sulphur removal efficiency of 97.2%). However, the process cooled the gases which caused ‘plume-droop’ under certain atmospheric conditions, causing a fume nuisance at ground level.'Children to survey pollution', The Times, 19 June 1972, p.14. Contaminated water from the flue-gas washing plant was treated in tanks through which air was bubbled, this oxidised the sulphite to sulphate, the water was diluted with water from the condensers before being returned to the river.
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Hoffman voltameter connected to a direct current power supply If the above described processes occur in pure water, H+ cations will be consumed/reduced at the cathode and OH− anions will be consumed/oxidised at the anode. This can be verified by adding a pH indicator to the water: the water near the cathode is basic while the water near the anode is acidic. The negative hydroxide ions that approach the anode mostly combine with the positive hydronium ions (H3O+) to form water. The positive hydronium ions that approach the cathode mostly combine with negative hydroxide ions to form water.
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Radon hexafluoride (), the heavier homologue of xenon hexafluoride, has been studied theoretically, but its synthesis has not yet been confirmed. Higher fluorides of radon may have been observed in experiments where unknown radon-containing products distilled together with xenon hexafluoride, and perhaps in the production of radon trioxide: these may have been RnF4, RnF6, or both. It is likely that the difficulty in identifying higher fluorides of radon stems from radon being kinetically hindered from being oxidised beyond the divalent state. This is due to the strong ionicity of RnF2 and the high positive charge on Rn in RnF+.
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Coated in pink-coloured sugar, an analysis of the pills conducted in 1909 for the British Medical Association revealed them to contain sulphate of iron, potassium carbonate, magnesia, powdered liquorice, and sugar. Approximately one third of the iron sulphate in the pills had oxidised in the sampling analysed, leading to the statement that the pills had been "very carelessly prepared".Secret Remedies: What They Cost & What They Contain,British Medical Association, London 1909, pp170, 174-155. The formula went through several changes, and at one stage included the laxative aloe, the major ingredient of Beecham's Pills.
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His work is characterised by rough finishes, visible fingerprints, the use of oxidised silver, and mixing high and low materials, such as precious stones, plastic pearls, and glass gemstones. He uses lost wax casting, moulding, and reshaping of found materials to make his jewellery. In a 2015 interview Fritsch stated: > A key moment was while studying at the Munich academy around 1991/92 when > instead of melting down the old jewellery I bought for casting, I started to > fix the pieces instead. It was a revelation to be able to use those pre- > existing often conventional pieces of jewellery.
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Acetaldehyde may be prepared from ethylene via the Wacker process, and then oxidised as above. In more recent times, chemical company Showa Denko, which opened an ethylene oxidation plant in Ōita, Japan, in 1997, commercialised a cheaper single-stage conversion of ethylene to acetic acid. The process is catalyzed by a palladium metal catalyst supported on a heteropoly acid such as silicotungstic acid. Similar process use the same metal catalyst on silicotungstic acid and silica: :C2H4 \+ O2 → CH3CO2H It is thought to be competitive with methanol carbonylation for smaller plants (100–250 kt/a), depending on the local price of ethylene.
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However, PSII has an additional function over the bacterial system. At the oxidising side of PSII, a redox-active residue in the D1 protein reduces P680, the oxidised tyrosine then withdrawing electrons from a manganese cluster, which in turn withdraw electrons from water, leading to the splitting of water and the formation of molecular oxygen. PSII thus provides a source of electrons that can be used by photosystem I to produce the reducing power (NADPH) required to convert CO2 to glucose. Instead of assigning specialized roles to quinones, the PsaA-PsaB photosystem I centre evolved to make both quinones immobile.
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Methane, a VOC whose atmospheric concentration has increased tremendously during the last century, contributes to ozone formation but on a global scale rather than in local or regional photochemical smog episodes. In situations where this exclusion of methane from the VOC group of substances is not obvious, the term Non-Methane VOC (NMVOC) is often used. The chemical reactions involved in tropospheric ozone formation are a series of complex cycles in which carbon monoxide and VOCs are oxidised to water vapour and carbon dioxide. The reactions involved in this process are illustrated here with CO but similar reactions occur for VOC as well.
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General mechanism in the Stickland fermentation Stickland fermentation exempflified with D-alanine and glycine Stickland fermentation or The Stickland Reaction is the name for a chemical reaction that involves the coupled oxidation and reduction of amino acids to organic acids. The electron donor amino acid is oxidised to a volatile carboxylic acid one carbon atom shorter than the original amino acid. For example, alanine with a three carbon chain is converted to acetate with two carbons. The electron acceptor amino acid is reduced to a volatile carboxylic acid the same length as the original amino acid.
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All of the fountains represent themes from classical mythology, including Greek deities, allegories and scenes from myths. They are cast in lead to prevent corrosion, and painted over to simulate bronze, a nobler material, or lacquered over white oxidised lead to imitate marble. A group of richly sculptural vases have been attributed to designs by the "dazzling maverick" Gilles-Marie Oppenord,Bruno Pons, "Oppenord and the Granja de San Ildefonso" The Burlington Magazine 131 No. 1034 (May 1989), pp. 337-341, based on drawings at the Victoria and Albert Museum and among Robert de Cotte's papers at the Bibliothèque Nationale.
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Long afterwards, the chamber roof collapsed violently under the weight of the mound, compressing the ship's contents into a seam of earth. It is thought that the helmet was shattered either by the collapse of the burial chamber or by the force of another object falling on it. The fact that the helmet had shattered meant that it was possible to reconstruct it. Had the helmet been crushed before the iron had fully oxidised, leaving it still pliant, the helmet would have been squashed, leaving it in a distorted shape similar to the Vendel and Valsgärde helmets.
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The G3P is converted to 1,3-bisphosphoglycerate int the presence of enzyme glyceraldehyde-3-phosphate dehydrogenase (an oxido- reductase). The aldehyde groups of the triose sugars are oxidised, and inorganic phosphate is added to them, forming 1,3-bisphosphoglycerate. The hydrogen is used to reduce two molecules of NAD+, a hydrogen carrier, to give NADH + H+ for each triose. Hydrogen atom balance and charge balance are both maintained because the phosphate (Pi) group actually exists in the form of a hydrogen phosphate anion (HPO42−), which dissociates to contribute the extra H+ ion and gives a net charge of -3 on both sides.
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Some of these soils are, in fact, red. For example, in the UK reddish brown earths occur on the Old Red Sandstone (Devonian) and the New Red Sandstone (Permian), and are red because the rocks from which they formed are derived from strongly oxidised deposits that were laid down under desert conditions millions of years ago. In long-cultivated soils the pH in the topsoil tends to be higher (more alkaline) than in the subsoil as a result of the addition of lime over the years. In general, the wetter the climate, the more acidic the soils. This is because rain tends to wash the “alkaline” bases out of the soil.
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Praseodymium metal tarnishes slowly in air, forming a spalling oxide layer like iron rust; a centimetre-sized sample of praseodymium metal corrodes completely in about a year. It burns readily at 150 °C to form praseodymium (III,IV) oxide, a nonstoichiometric compound approximating to Pr6O11: :12 Pr + 11 O2 → 2 Pr6O11 This may be reduced to praseodymium(III) oxide (Pr2O3) with hydrogen gas.Greenwood and Earnshaw, pp. 1238–9 Praseodymium(IV) oxide, PrO2, is the most oxidised product of the combustion of praseodymium and can be obtained by either reaction of praseodymium metal with pure oxygen at 400 °C and 282 bar or by disproportionation of Pr6O11 in boiling acetic acid.
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The small fleet meant overall ozone-layer degradation caused by Concorde was negligible. In 1995, David Fahey, of the National Oceanic and Atmospheric Administration in the United States, warned that a fleet of 500 supersonic aircraft with exhausts similar to Concorde might produce a 2 percent drop in global ozone levels, much higher than previously thought. Each 1 percent drop in ozone is estimated to increase the incidence of non-melanoma skin cancer worldwide by 2 percent. Dr Fahey said if these particles are produced by highly oxidised sulphur in the fuel, as he believed, then removing sulphur in the fuel will reduce the ozone-destroying impact of supersonic transport.
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Despite its promising start, in 1872 the Ravenswood goldfield entered a "period of depression",Maclaren, "Report on the Geology and Reefs of the Ravenswood Gold Field", p.2 as its most important mines reached the water table at about deep - starting with the Sunset in 1871, followed by the General Grant, Black Jack, and Melaneur in 1872.Menghetti, Ravenswood: Five heritage trails, p.6 Although the oxidised quartz ('red stone' or "brown stone" quartz) close to the surface yielded its gold to traditional methods of mechanical crushing, below the water table the gold was in fine particles, which was not easily recovered by mechanical means.
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IR spectrum showing carbonyl absorption due to oxidative degradation of polypropylene crutch moulding Polymers are susceptible to attack by atmospheric oxygen, especially at elevated temperatures encountered during processing to shape. Many process methods such as extrusion and injection moulding involve pumping molten polymer into tools, and the high temperatures needed for melting may result in oxidation unless precautions are taken. For example, a forearm crutch suddenly snapped and the user was severely injured in the resulting fall. The crutch had fractured across a polypropylene insert within the aluminium tube of the device, and infra-red spectroscopy of the material showed that it had oxidised, possibly as a result of poor moulding.
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The statue of Cooke is not marble, but copper, like most other architecture around the city of Belfast around the same time. Due to exposure to the elements, most of these statues and domes around the city have oxidised, producing a green colour of copper oxide, especially noticeable on the nearby City Hall. Other specialist colleges were subsequently established in the city including Stanhope Street, Rupert Stanley, and the College of Business Studies in Brunswick Street. In the early 1990s, these colleges amalgamated as the Belfast Institute of Further and Higher Education which in turn merged with Castlereagh College to form the current college in 2007.
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Compounds of cobalt in the +3 oxidation state exist, such as cobalt(III) fluoride , nitrate , and sulfate ; however, cobalt(III) chloride is not stable in normal conditions, and would decompose immediately into and chlorine.Handbook of Chemistry and Physics, 71st edition, CRC Press, Ann Arbor, Michigan, 1990. On the other hand, cobalt(III) chlorides can be obtained if the cobalt is bound also to other ligands of greater Lewis basicity than chloride, such as amines. For example, in the presence of ammonia, cobalt(II) chloride is readily oxidised by atmospheric oxygen to hexamminecobalt(III) chloride: :4 ·6 + 4 Cl + 20 + → 4 + 26 Similar reactions occur with other amines.
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The ore profile of the 132 North deposit is, from base upwards, 0.1 to 1m of massive pentlandite-pyrrhotite-pyrite-chalcopyrite sulfide, matrix sulfide containing 40-80% sulfide, and disseminated sulfide. Accessory nickeline and gersdorffite are reported. The transition zone supergene sulfide phases include; violarite, smythite, covellite, chalcocite and marcasite after pyrite. The nickel sulfides within the regolith have been oxidised into a complex series of weathering fronts including a rare expression of a carbonate front which has resulted in a host of unusual nickel carbonate, arsenate and silicate minerals such as gaspeite, atacamite, annabergite, carrboydite, glaucospaerite, hydrohonessite, kambaldaite, népouite, nullaginite, pecoraite, olivenite, otwayite, reevesite, retgersite, takovite and of course widgiemoolthalite.
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Type E were different from the Asian lacquers judging from the distinctive surface appearances, different flow and expressions. A series of scientific analysis including cross-section optical microscopy observation, staining tests,Odegaard, N./Carroll, S./Zimmt, W. S., Material characterization tests for objects of art and archaeology, London 2005, p. 45. GC-MS and Py-GC-MS were performed on these precious lacquers. Results illustrated that objects were multi-layer structured, the lacquer layer was mainly composed of aged laccol with some urushiol, drying oil and cedrol oil, the coating was based on oxidised shellac and oil-resinous varnish composed of linseed oil and Manila copal among the Chinese lacquers.
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Wurster's blue is the trivial name given to the chemical N,N,N′,N′-tetramethyl-p-phenylenediamine, also known as TMPD. It is an easily oxidised phenylenediamine, which loses two electrons in one-electron oxidation steps; the radical cation is a characteristic blue-violet colour, which gives the compound part of its name. The remaining part of its name comes from its discoverer, the German chemist Casimir Wurster (7 August 1854 – 29 November 1913). The hydrochloride salt finds use as a redox indicator in the oxidase test and is also used in electron transport chain analysis as it is capable of donating electrons to cytochrome c.
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The cliffs of Alum Bay, showing the steeply-dipping multi-coloured sands above the white Chalk, with shallower dips towards the northern end Alum Bay is the location of a classic sequence of upper Paleocene and Eocene beds of soft sands and clays, separated by an unconformity from the underlying Cretaceous Chalk Formation that forms the adjoining headland of West High Down. Due to geological folding of the Alpine orogeny, the strata in the main section of the bay are near vertical, with younger rocks with progressively lower dips to the west. The sands are coloured due to oxidised iron compounds formed under different conditions.West, I.M. and Helsby, R. 2007.
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The preparation of pyrithione was first reported in 1950 by Shaw and was prepared by reaction of 2-chloropyridine N-oxide with sodium hydrogensulfide followed by acidification, or more recently with sodium sulfide. 2-chloropyridine N-oxide itself can be prepared from 2-chloropyridine using peracetic acid. Another approach involves treating the same starting N-oxide with thiourea to afford pyridyl-2-isothiouronium chloride N-oxide which undergoes base hydrolysis to pyrithione. 2-Bromopyridine can be oxidised to its N-oxide using a suitable peracid (as per 2-chloropyridine), both approaches being analogous to that reported in Organic Syntheses for the oxidation of pyridine to its N-oxide.
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Akali Phula Singh. gouache, with oxidised gold Akali Phula Singh did not like that Maharajah Ranjit Singh replaced the Bani (Language) and Bana (Clothing) of the traditional Sikh appearance blessed by the Sikh gurus, as the national army military drills were now being done in French and the traditional Bana dress was replaced with European clothing. Akali Phula Singh disapproved the treaty that Ranjit Singh created with the British Raj as he had wanted the Sikh Empire to retake all of India from the British. The Maharajah then calmed the warrior by telling him they would first subdue the Punjab, Kashmir and Tibet before taking on the British.
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Antlerite is a greenish hydrous copper sulfate mineral, with the formula Cu3(SO4)(OH)4. It occurs in tabular, acicular, or fibrous crystals with a vitreous luster. Originally believed to be a rare mineral, antlerite was found to be the primary ore of the oxidised zones in several copper mines across the world, including the Chuquicamata mine in Chile, and the Antler mine in Arizona, US from which it takes its name. It is chemically and optically similar in many respects to other copper minerals such as malachite and brochantite, though it can be distinguished from the former by a lack of effervescence in hydrochloric acid.
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Based on the analysis of rat and human urine by gas chromatography and mass spectrometry, mephedrone is thought to be metabolised by three phase 1 pathways. It can be demethylated to the primary amine (producing compounds 2, 3 and 5), the ketone group can be reduced (producing 3) or the tolyl group can be oxidised (producing 6). Both 5 and 6 are thought to be further metabolised by conjugation to the glucuronide and sulfate derivatives. Knowledge of the primary routes of metabolism should allow the intake of mephedrone to be confirmed by drug tests, as well as more accurate determination of the causes of side effects and potential for toxicity.
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Straits undertook a resource definition drilling programme and upgraded the resource to around 10 million tonnes of ore grading 1% copper, predominantly composed of oxidised copper minerals such as malachite, azurite, chalcocite and chrysocolla. Other minerals noted within the ore bodies are willemite, sphalerite, chalcopyrite and rare native copper. The majority of resources were defined at the Mons Cupri deposit and the Whim Creek deposit. Straits Resources Limited, after closure of the Girilambone Copper Mine in 2001-02, investigated the feasibility of translocating the solvent extraction and electrowinning plant from New South Wales to Whim Creek to set up a large scale open cut oxide copper SX-EW heap leach operation.
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A caesium-antimony cathode gives a device that is very sensitive in the violet to ultra-violet region with sensitivity falling off to blindness to red light. Caesium on oxidised silver gives a cathode that is most sensitive to infra-red to red light, falling off towards blue, where the sensitivity is low but not zero.Mullard Technical Handbook Volume 4 Section 4:Photoemissive Cells (1960 Edition) Vacuum devices have a near constant anode current for a given level of illumination relative to anode voltage. Gas-filled devices are more sensitive, but the frequency response to modulated illumination falls off at lower frequencies compared to the vacuum devices.
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The NSW Government Architect's Office's Ken Woolley designed a 38-floor tower of composite concrete and steel with deep window recesses clad in black granite. Woolley's design accounted for the sun-exposure for such a tall building by including measures such as floor slabs projecting beyond the window line to make sunhoods, which were clad in bronze sheeting. Woolley also designed the interiors which were influenced by Scandinavian modernism exemplified by the use of modular furniture. The lift lobby leading for the Premier's office floor was decorated by a double-sided oxidised bronze Coat of Arms of New South Wales by sculptor Bert Flugelman.
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She then received an honours degree from the Department of Experimental Pharmacology and Toxicology at Adelaide University and a PhD in cell biology from Sydney Medical School in 2005. Her PhD dissertation examined the mechanisms of impaired degradation of oxidised proteins with a focus on the consequences for heart disease. She worked as a medical researcher at the Heart Research Institute in Camperdown, New South Wales, and is currently a postdoctoral fellow at the University of Technology, Sydney, where she studies ageing disorders and motor neurone disease. She is also on the editorial board for the peer-reviewed journal Focus on Alternative and Complementary Therapies.
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Molten iron from the ladle is added as required for the charge balance. A typical chemistry of hotmetal charged into the BOS vessel is: 4% C, 0.2–0.8% Si, 0.08%–0.18% P, and 0.01–0.04% S, all of which can be oxidised by the supplied oxygen except sulphur.(which requires reducing conditions) # The vessel is then set upright and a water-cooled, copper tipped lance with 3–7 nozzles is lowered into it and high purity oxygen is delivered at supersonic speeds. The lance "blows" 99% pure oxygen over the hot metal, igniting the carbon dissolved in the steel, to form carbon monoxide and carbon dioxide, causing the temperature to rise to about 1700 °C.
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The Rocketdyne division of North American Aviation developed a relatively small liquid-fuelled rocket engine for thrust augmentation of manned aircraft during the late 1950s. The AR2 is a single-chamber rocket engine burning kerosene (JP-4 or JP-5) jet fuel, oxidised with 90% High Test Peroxide (H2O2 / HTP), allowing the engine to use the same fuel as an aircraft fuel system. The variable-thrust AR2 is a direct development of the fixed thrust AR1, which was given the military designation LR36. The AR2-3 had variable-thrust and single lever throttle control, regulating flow of oxidiser to the turbo-pump gas- generator and thus flow of propellants to the combustion chamber.
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Methemoglobinaemia is a form of abnormal hemoglobin where the iron centre has been oxidised from the ferrous +2 oxidation state (the normal form) to the ferric +3 state. This causes a leftward shift in the oxygen hemoglobin dissociation curve, as any residual heme with oxygenated ferrous iron (+2 state) is unable to unload its bound oxygen into tissues (because 3+ iron impairs hemoglobin's cooperativity), thereby increasing its affinity with oxygen. However, methemoglobin has increased affinity for cyanide, and is therefore useful in the treatment of cyanide poisoning. In cases of accidental ingestion, administration of a nitrite (such as amyl nitrite) can be used to deliberately oxidise hemoglobin and raise methemoglobin levels, restoring the functioning of cytochrome oxidase.
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The vinyl ferrocene can be converted into a polymer (polyvinylferrocene, PVFc), a ferrocenyl version of polystyrene (the phenyl groups are replaced with ferrocenyl groups). Another polyferrocene which can be formed is poly(2-(methacryloyloxy)ethyl ferrocenecarboxylate), PFcMA. In addition to using organic polymer backbones, these pendant ferrocene units have been attached to inorganic backbones such as polysiloxanes, polyphosphazenes, and polyphosphinoboranes, (-PH(R)-BH2-)n, and the resulting materials exhibit unusual physical and electronic properties relating to the ferrocene / ferrocinium redox couple. Both PVFc and PFcMA have been tethered onto silica wafers and the wettability measured when the polymer chains are uncharged and when the ferrocene moieties are oxidised to produce positively charged groups.
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This concept has previously been explored as a means to circumvent the unwanted release of potentially pathogenic genetically modified bacteria. It was proposed that an auxotrophic strain of Escherichia coli (X1776) could be used for all genetic modification practices, as the strain is unable to survive without the supplementation of DAP, and thus, cannot live outside of a laboratory environment. Lysine has also been proposed to be involved in calcium intestinal absorption and renal retention, and thus, may play a role in calcium homeostasis. Finally, lysine has been shown to be a precursor for carnitine, which transports fatty acids to the mitochondria, where they can be oxidised for the release of energy.
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Enzymes with single-substrate mechanisms include isomerases such as triosephosphateisomerase or bisphosphoglycerate mutase, intramolecular lyases such as adenylate cyclase and the hammerhead ribozyme, an RNA lyase. However, some enzymes that only have a single substrate do not fall into this category of mechanisms. Catalase is an example of this, as the enzyme reacts with a first molecule of hydrogen peroxide substrate, becomes oxidised and is then reduced by a second molecule of substrate. Although a single substrate is involved, the existence of a modified enzyme intermediate means that the mechanism of catalase is actually a ping–pong mechanism, a type of mechanism that is discussed in the Multi- substrate reactions section below.
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The Medal "Veteran of the Armed Forces of the USSR" was a 32mm in diameter silver- plated tombac circular medal with a raised rim. The obverse was oxidised, it bore at its upper section a ruby-red enamelled five pointed star superimposed on the relief image of the hammer and sickle, just below in the center, the relief inscription "USSR" () over a curled laurel branch; at the bottom along the medal circumference, a relief scroll with the inscription in prominent letters "VETERAN OF THE ARMED FORCES" (). The reverse was plain with a matte finish. The medal was secured to a standard Soviet pentagonal mount by a ring through the medal suspension loop.
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Natural peatlands do not always have a measurable cooling effect on the climate in a short time span as the cooling effects of sequestering carbon are offset by the emission of methane, which is a strong greenhouse gas. However, given the short "lifetime" of methane (12 years), it is often said that methane emissions are unimportant within 300 years compared to carbon sequestration in wetlands. Within that time frame or less, most wetlands become both net carbon and radiative sinks. Hence, peatlands do result in cooling of the Earth's climate over a longer time period as methane is oxidised quickly and removed from the atmosphere whereas atmospheric carbon dioxide is continuously absorbed.
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The following reaction is catalyzed by thymidylate synthase: : 5,10-methylenetetrahydrofolate + dUMP \rightleftharpoons dihydrofolate + dTMP By means of reductive methylation, deoxyuridine monophosphate (dUMP) and N5,N10-methylene tetrahydrofolate are together used to form dTMP, yielding dihydrofolate as a secondary product. This provides the sole de novo pathway for production of dTMP and is the only enzyme in folate metabolism in which the 5,10-methylenetetrahydrofolate is oxidised during one- carbon transfer. The enzyme is essential for regulating the balanced supply of the 4 DNA precursors in normal DNA replication: defects in the enzyme activity affecting the regulation process cause various biological and genetic abnormalities, such as thymineless death. The enzyme is an important target for certain chemotherapeutic drugs.
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Another polymer which can be formed is poly( ferrocenecarboxylate), PFcMA. Both PVFc and PFcMA have been tethered onto silica wafers and the wettability measured when the polymer chains are uncharged and when the ferrocene moieties are oxidised to produce positively charged groups, as illustrated at right. The contact angle with water on the PFcMA-coated wafers was 70° smaller following oxidation, while in the case of PVFc the decrease was 30°, and the switching of wettability has been shown to be reversible. In the PFcMA case, the effect of longer chains with more ferrocene groups (and also greater molar mass) has been investigated, and it was found that longer chains produce significantly larger contact angle reductions.
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The HO2 radical produced by the reaction of OH with O3 is recycled to OH by reaction with oxygen atoms or ozone. In addition, solar proton events can significantly affect ozone levels via radiolysis with the subsequent formation of OH. Nitrous oxide (N2O) is produced by biological activity at the surface and is oxidised to NO in the stratosphere; the so-called NOx radical cycles also deplete stratospheric ozone. Finally, chlorofluorocarbon molecules are photolysed in the stratosphere releasing chlorine atoms that react with ozone giving ClO and O2. The chlorine atoms are recycled when ClO reacts with O in the upper stratosphere, or when ClO reacts with itself in the chemistry of the Antarctic ozone hole.
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Metmyoglobin is the oxidised form of the oxygen-carrying hemeprotein myoglobin. Metmyoglobin is the cause of the characteristic brown colouration of meat that occurs as it ages. In living muscle, the concentration of metmyoglobin is vanishingly small, due to the presence of the enzyme metmyoglobin reductase, which, in the presence of the cofactor NADH and the coenzyme cytochrome b4 converts the Fe3+ in the heme prosthetic group of metmyoglobin back to the Fe2+ of normal myoglobin. In meat, which is dead muscle, the normal processes of removing metmyoglobin are prevented from effecting this repair, or alternatively the rate of metmyoglobin formation exceeds their capacity, so that there is a net accumulation of metmyoglobin as the meat ages.
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Since the iodide ion is a mild reducing agent, is easily oxidised to by powerful oxidising agents such as chlorine: : This reaction is employed in the isolation of iodine from natural sources. Air will oxidize iodide, as evidenced by the observation of a purple extract when aged samples of KI are rinsed with dichloromethane. As formed under acidic conditions, hydriodic acid (HI) is a stronger reducing agent.N. N. Greenwood, A. Earnshaw, Chemistry of the Elements, Pergamon Press, Oxford, UK, 1984Handbook of Chemistry and Physics, 71st edition, CRC Press, Ann Arbor, Michigan, 1990The Merck Index, 7th edition, Merck & Co., Rahway, New Jersey, 1960 Like other iodide salts, forms when combined with elemental iodine.
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Thallium triiodide is a chemical compound of thallium and iodine with formula TlI3. Unlike the other thallium trihalides, which contain thallium(III), is a thallium(I) salt and contains the triiodide ion, I3−. An appreciation as to why Tl+ is not oxidised to Tl3+ in the reaction: : Tl3+ \+ 2 I− → Tl+ \+ I2 can be gained by considering the standard reduction potentials of the half cells which are: : Tl3+ \+ 2 → Tl+; Er° = 1.252 : I2 \+ 2 → 2 I−; Er° = 0.5355 The favoured reaction is therefore the reduction of Tl3+ (1.252 > 0.5355). Using standard electrode potentials in this way must be done with caution as factors such as complex formation and solvation may affect the reaction.
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The five active chimneys of Loki's Castle are venting water as hot as 300 °C (570 °F) and sit on a vast mound of sulfide minerals which is about 825 ft (250 m) in diameter at its base, and some 300 feet (90 m) across its top. A member of the 2008 expedition, oceanographer Marvin Lilley has speculated that this may be the largest such deposit ever seen on the sea floor. The active chimneys are mostly black in colour, but are covered with mats of white bacteria which are living on minerals and materials emitted by the vents. The older chimneys are a mottled red colour, due to the presence of deposits of oxidised iron.
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This reaction produces oxidised α-tocopheroxyl radicals that can be recycled back to the active reduced form through reduction by other antioxidants, such as ascorbate, retinol or ubiquinol. This is in line with findings showing that α-tocopherol, but not water-soluble antioxidants, efficiently protects glutathione peroxidase 4 (GPX4)-deficient cells from cell death. GPx4 is the only known enzyme that efficiently reduces lipid-hydroperoxides within biological membranes. However, the roles and importance of the various forms of vitamin E are presently unclear, and it has even been suggested that the most important function of α-tocopherol is as a signaling molecule, with this molecule having no significant role in antioxidant metabolism.
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The Petrochemicals Division of Imperial Chemical Industries (ICI) operated many plants with large inventories of flammable chemicals at its Wilton site (including one in which cyclohexane was oxidised to cyclohexanone and cyclohexanol). Historically good process safety performance at Wilton had been marred in the late 1960s by a spate of fatal fires caused by faulty isolations/handovers for maintenance work. Their immediate cause was human error but ICI felt that saying that most accidents were caused by human error was no more useful than saying that most falls are caused by gravity. ICI had not simply reminded operators to be more careful, but issued explicit instructions on the required quality of isolations, and the required quality of its documentation.
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Since all the sample is oxidised or reduced during the potential sweep, the peak current and peak area should be proportional to scan rate (observing that the peak current is proportional to scan rate proves that the redox species that gives the peak is actually immobilised). The same is true for experiments performed with non- biological redox molecules adsorbed onto electrodes. The theory was mainly developed by the French electrochemist Etienne Laviron in the 1980s,,. Since both this faradaic current (which results from the oxidation/reduction of the adsorbed molecule) and the capacitive current (which results from electrode charging) increase in proportion to scan rate, the peaks should remain visible when the scan rate is increased.
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In 1999 researchers in Glasgow University found that an oxidised derivative of thymosin β4 (the sulfoxide, in which an oxygen atom is added to the methionine near the N-terminus) exerted several potentially anti-inflammatory effects on neutrophil leucocytes. It promoted their dispersion from a focus, inhibited their response to a small peptide (F-Met- Leu-Phe) which attracts them to sites of bacterial infection and lowered their adhesion to endothelial cells. (Adhesion to endothelial cells of blood vessel walls is pre-requisite for these cells to leave the bloodstream and invade infected tissue). A possible anti-inflammatory role for the β4 sulfoxide was supported by the group's finding that it counteracted artificially-induced inflammation in mice.
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The lower iodides ThI3 (black) and ThI2 (gold) can be prepared by reducing the tetraiodide with thorium metal. (ThI is also predicted to form as an intermediate in the dissociation of ThI4 to thorium metal.) These do not contain Th(III) and Th(II), but instead contain Th4+ and could be more clearly formulated as and respectively. Depending on the amount of time allowed for the reaction between ThI4 and thorium, two modifications of ThI3 can be produced: shorter times give thin lustrous rods of α-ThI3, while longer times give small β-ThI3 crystals with green to brass-coloured luster. Both forms are quickly oxidised by air and reduce water, quickly forming large quantities of hydrogen gas.
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Dirhenium decacarbonyl is the most common entry to organorhenium chemistry. Its reduction with sodium amalgam gives Na[Re(CO)5] with rhenium in the formal oxidation state −1. Dirhenium decacarbonyl can be oxidised with bromine to bromopentacarbonylrhenium(I): :Re2(CO)10 \+ Br2 → 2 Re(CO)5Br Reduction of this pentacarbonyl with zinc and acetic acid gives pentacarbonylhydridorhenium: :Re(CO)5Br + Zn + HOAc → Re(CO)5H + ZnBr(OAc) Methylrhenium trioxide ("MTO"), CH3ReO3 is a volatile, colourless solid has been used as a catalyst in some laboratory experiments. It can be prepared by many routes, a typical method is the reaction of Re2O7 and tetramethyltin: :Re2O7 \+ (CH3)4Sn → CH3ReO3 \+ (CH3)3SnOReO3 Analogous alkyl and aryl derivatives are known.
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These include acid rain where sulfur dioxide in the airshed is dissolved in rainfall to produce sulfurous acid. In lightning storms, the dioxide is oxidised to trioxide making the residual sulfuric acid in rainfall even more highly acidic. Local government infrastructure is most commonly corroded by sulfate arising from the oxidation of sulfide which occurs when bacteria (for example in sewer mains) reduce the ever-present hydrogen sulfide gas to a film of sulfide (S-) or bi-sulfide (HS-) ions. This reaction is reversible, both readily oxidising on exposure to air or oxygenated stormwater, to produce sulfite or sulfate ions and acidic hydrogen ions in the reaction HS− \+ H2O+ O2 -> 2H+ \+ SO4-.
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This results in the separation of oxidised ferric compounds from paramagnetic chromite components within the ore at the reactor outlet where the product may be further refined to synthesize iron or rutile downstream. In roasting gold-bearing sulfide ores, sulfur or arsenic diffusion gradients encourage the migration of gold towards mineral pores. Hence, continual roasting and volatilisation of sulfur and arsenic allows for the coalescence of gold at the surface of mineral particles which can then be separated efficiently by downstream processes such as leaching. In a FR, the high throughput implies a high particle concentration per unit volume of gas and hence a large contact area of reaction for mass transfer.
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The chemistry sets the voltage and the oxygen concentration controls the electric current output. If an electrical load is connected across the cell it can draw up to this current but if the cell is overloaded the voltage will drop. When the lead electrode has been substantially oxidised, the maximum current that the cell can produce will drop, and eventually linearity of output voltage to partial pressure of oxygen at the reactive surface will fail within the required range of measurement, and the cell will no longer be accurate. There are two commonly used ways to specify expected sensor life span: The time in months at room temperature in air, or volume percentage oxygen hours (Vol%O2h).
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Following apoptosis, the dying cells need to be taken up into the surrounding tissues by macrophages in a process called efferocytosis. One of the features of an apoptotic cell is the presentation of a variety of intracellular molecules on the cell surface, such as calreticulin, phosphatidylserine (from the inner layer of the plasma membrane), annexin A1, oxidised LDL and altered glycans. These molecules are recognised by receptors on the cell surface of the macrophage such as the phosphatidylserine receptor or by soluble (free-floating) receptors such as thrombospondin 1, GAS6, and MFGE8, which themselves then bind to other receptors on the macrophage such as CD36 and alpha-v beta-3 integrin. Defects in apoptotic cell clearance is usually associated with impaired phagocytosis of macrophages.
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The two DNA-binding motifs (a zinc finger and the H2TH (helix-two-turns-helix) motifs) suggest that the oxidised base is flipped out from double-stranded DNA in the binding mode and excised by a catalytic mechanism similar to that of bifunctional base excision repair enzymes. Fpg binds one ion of zinc at the C terminus, which contains four conserved and essential cysteines. Endonuclease VIII (Nei) has the same enzyme activities as Fpg above (,), but with a preference for oxidized pyrimidines, such as thymine glycol, 5,6-dihydrouracil and 5,6-dihydrothymine. These proteins contain three structural domains: an N-terminal catalytic core domain, a central helix-two turn-helix (H2TH) module and a C-terminal zinc finger (see PDB:1K82).
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Photocatalyst activity indicator inks (Paii's) are a recent advance in the visual demonstration of photocatalysis and the assessment of the activity of photocatalyst materials. They are an inexpensive, easy to use and provide a very quick route to demonstrating the presence of a photocatalytic film, even under low levels of UV light. Unlike the photo-oxidative bleaching of methylene blue, they use the underlying semiconductor photocatalyst film to photoreduce the dye (Dox in figure 2), in the ink coating, to another (usually colourless) form, (Dred in figure 2) whilst simultaneously oxidising an easily oxidised organic species, a sacrificial electron donor (SED), such as glycerol, which is also present in the ink. The kinetics of reduction of the dye in a paii have been studied in great detail.
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The aldehydes and ketones provided material for his earlier work. He observed that aldehydes and ketones may suffer reduction in neutral, alkaline, and sometimes acid solution to secondary and tertiary glycols, substances which he named pinacones; and also that certain pinacones when distilled with dilute sulfuric acid gave compounds, which he named pinacolines. The unsaturated acids also received much attention, and he discovered the internal anhydrides of oxyacids, termed lactones. He also discovered what is now known as the pinacol rearrangement, whereby 1,2-diols rearrange to aldehydes or ketones under acid catalysis. His work involved the preparation of 2,3-dimethyl-2,3-butanediol (pinacol) from acetone, followed by the rearrangement to 3,3-dimethylbutanone (pinacolone), which was then oxidised with dichromate to trimethylacetic acid.
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Gadolinium-doped ceria (GDC) (known alternatively as gadolinia-doped ceria, gadolinium-doped cerium oxide, cerium(IV) oxide, gadolinium-doped, and GCO, formula Gd:CeO2) is a ceramic electrolyte used in solid oxide fuel cells (SOFCs). It has a cubic structure and a density of around 7.2 g/cm3 in its oxidised form. It is one of a class of ceria-doped electrolytes with higher ionic conductivity and lower operating temperatures (<700 °C) than those of yttria-stabilized zirconia, the material most commonly used in SOFCs. Because YSZ requires operating temperatures of 800–1000 °C to achieve maximal ionic conductivity, the associated energy and costs make GDC a more optimal (even "irreplaceable", according to researchers from the Fraunhofer Society) material for commercially viable SOFCs.
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Most of the information on mechanism comes from work on the pea cytosolic and soybean cytosolic enzymes. The mechanism of oxidation of ascorbate is achieved by means of an oxidized Compound I intermediate, which is subsequently reduced by substrate in two, sequential single electron transfer steps (equations [1]–[3], where HS = substrate and S• = one electron oxidised form of substrate). :APX + H2O2 → Compound I + H2O [1] :Compound I + HS → Compound II + S• [2] :Compound II + HS → APX + S• \+ H2O [3] In ascorbate peroxidase, Compound I is a transient (green) species and contains a high- valent iron species (known as ferryl heme, FeIV) and a porphyrin pi-cation radical,, as found in horseradish peroxidase. Compound II contains only the ferryl heme.
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The mechanism of thiol–disulfide exchange between oxidoreductases is understood to begin with the nucleophilic attack on the sulfur atoms of a disulfide bond in the oxidised partner, by a thiolate anion derived from a reactive cysteine in a reduced partner. This generates mixed disulfide intermediates, and is followed by a second, this time intramolecular, nucleophilic attack by the remaining thiolate anion in the formerly reduced partner, to liberate both oxidoreductases. The balance of evidence discussed thus far supports a model in which oxidising equivalents are sequentially transferred from Ero1 via a thiol–disulfide exchange reaction to PDI, with PDI then undergoing a thiol–disulfide exchange with the nascent polypeptide, thereby enabling the formation of disulfide bonds within the nascent polypeptide.
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13-Vanadonickelate(IV) compounds such as K7NiV13O38 with black octahedral crystals exist. It can be made from isopolyvanadate, with nickel(II) oxidised by peroxydisulfate at a pH around 4. Nickel(IV) heteropolyniobates such as the dark maroon Na12NiNb12O38 are also known. An alternate orange red hydrate perhaps with 44 water molecules also exists. With nickel-II (tetramethylammonium)6[H3NiNb9O28 forms a green salt that is very soluble in water, but hardly soluble in ethanol. H43K14Na6Nb32 Ni10O183 is a nickel- cation-bridged polyoxoniobate which crystallizes in the monoclinic system with cell dimensions a=15.140 b=24.824 c=25.190 Å and β=103.469 and two formulas per unit cell. Na8Li12[Ni2(P2W15O56)2] forms a sandwich structure, and Na4Li5[Ni3(OH)3(H2O)3P2W16O59] is a Wells-Dawson polyoxometalate.
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The lithium economy concept is used primarily as a political argument to prevent over-domination of the post-carbon energy future by oil companies; and as a post-carbon economy on which action can be taken now instead of deferred to some future date (see FreedomCAR project). The lithium economy differs from the other proposed future fuel economies in that the transition roadmap begins with convencional recreable batteries using conventional Li-ion or Lithium polymer cell batteries and progressing to chemistries (such as Li-S and Li-iron-phosphate) and cell types with higher energy densities. Eventually, anode replacement Li-air or Li-water cells are envisaged where only anodes (lithium metal) are replaced. The energy is stored in unoxidised lithium atoms, which release energy when oxidised.
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Cornubite is a secondary mineral found in the oxidised zone of copper deposits. In Cornwall it is found in drusy quartz associated with malachite, Cu2(CO3)(OH)2, olivenite, Cu2(AsO4)(OH), cuprite, Cu2O, cornwallite, Cu2+5(AsO4)2(OH)2, and liroconite, Cu2+2Al(AsO4)(OH)4·4H2O. Some of the world’s best specimens come from the Majuba Hill Mine in the Antelope District, Nevada, US. Cornubite occurs there as light green botryoidal crusts on rhyolite or as balls and crusts on cornwallite, also as coatings on clinoclase and pseudomorphs after parnauite.Castor and Ferdock (2004) Minerals of Nevada, Nevada Bureau of Mines and Geology with the University of Nevada Press Other associations are with chalcophyllite, chenevixite, pseudomalachite, bayldonite, tyrolite, azurite and chrysocolla.
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The Radomiro Tomic deposit, 5 km north of the main pit, was discovered in 1952 when Anaconda conducted an extensive churn drilling programme to explore for oxidised ore to the north of the Chuquicamata pit. It was named Chuqui Norte but they did not develop it, largely because the technology had not been developed, particularly SX/EW. Two smaller areas of interest were found and the overall results showed that the Chuquicamata complex of mineralised porphyries is no less than 14 km long. The deposit is covered with some 100 metres of alluvium and in 1993/94 Codelco estimated a resource base for the operation of 802 million tonnes of oxide ore grading 0.59% copper and 1,600 million tonnes of refractory (sulphide) ore.
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Consequently it is a strong Lewis acid and reacts with any Lewis base, L to form an adduct. :BH3 \+ L → L—BH3 in which the base donates its lone pair, forming a dative covalent bond. Such compounds are thermodynamically stable, but may be easily oxidised in air. Solutions containing borane dimethylsulfide and borane–tetrahydrofuran are commercially available; in tetrahydrofuran a stabilising agent is added to prevent the THF from oxidising the borane.Hydrocarbon Chemistry, George A. Olah, Arpad Molner, 2d edition, 2003, Wiley-Blackwell A stability sequence for several common adducts of borane, estimated from spectroscopic and thermochemical data, is as follows: :PF3 < CO < Et2O < Me2O < C4H8O < C4H8S < Et2S < Me2S < Py < Me3N < H− BH3 has some soft acid characteristics as sulfur donors form more stable complexes than do oxygen donors.
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On the Mohs hardness scale, Opalstone rates between 5.0-5.5. Lemon Opal,Usually a much deeper colouration all over the stone, more colourful and a harder stone to sculpt than the usual Opal Stone, mostly due to the particles of quartz found within the stone. Lemon Opalstone is easily identified by contrasting yellow striations within the stone. On the Mohs hardness scale, Opalstone rates between 5.0-5.5. Springstone,Springstone is a very hard serpentine with high iron content and a fine texture, no cleavages, hard and firm offering a good resistance to the sculptor. Springstone has a rich outer "blanket" of reddish brown oxidised rock. They emerge from the quarry like sculptures created by nature millions of years ago and are often a source of inspiration to the artist.
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West Rigg Open Cutting is a Site of Special Scientific Interest in the Wear Valley district of west County Durham, England. It is a disused ironstone quarry, located just over 1 km north of the village of Westgate, in Weardale. At West Rigg, the Slitt Vein, a 20 km-long quartz intrusion in the Namurian Great Limestone, is exposed at the surface; the exposure is up to 5 m wide over a distance of some 200 m. During Late Permian times, extensive mineralisation occurred in the vicinity of the Slitt Vein: high salinity fluids, rich in iron, permeated the Great Limestone which, throughout its full thickness, was mineralised, producing siderite and ankerite minerals which were subsequently oxidised, yielding a limonitic ore with an iron content of over 40 percent.
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First, the transfer of an electron from BPh− to P960+ is relatively slow compared to two other redox reactions in the reaction center. The faster reactions involve the transfer of an electron from BPh− (BPh− is oxidised to BPh) to the electron acceptor quinone (QA), and the transfer of an electron to P960+ (P960+ is reduced to P960) from a heme in the cytochrome subunit above the reaction center. The high-energy electron that resides on the tightly bound quinone molecule QA is transferred to an exchangeable quinone molecule QB. This molecule is loosely associated with the protein and is fairly easy to detach. Two of the high-energy electrons are required to fully reduce QB to QH2, taking up two protons from the cytoplasm in the process.
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Two-dimensional representation of neuraminic acid in its straight chain form. Neuraminic acid (5-amino-3,5-dideoxy-D-glycero-D-galacto- non-2-ulosonic acid) is an acidic amino sugar with a backbone formed by nine carbon atoms. Although 9-carbon sugars do not occur naturally, neuraminic acid may be regarded as a theoretical 9-carbon ketose in which the first link of the chain (the –CH2OH at position 1) is oxidised into a carboxyl group (–C(=O)OH), the hydroxyl group at position 3 is deoxidised (oxygen is removed from it), and the hydroxyl group at position 5 is substituted with an amino group (–NH2). Neuraminic acid may also be visualized as the product of an aldol-condensation of pyruvic acid and D-mannosamine (2-amino-2-deoxy- mannose).
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Heat- bodied linseed oil, oxidised shellac, aged urushiol and soot or tar were also detected in the Japanese panels.Miklin-Kniefacz, S./ Miklin, R./ Kafer, S./ Schwetz, F./ Pitthard, V./ Stanek, S./ Griesser, M./ Parson, W., First investigation of the Asian lacquer panels in the “Chinese Cabinets”, Schönbrunn Palace, Vienna, p. 151. As for the European ones, traces of pine pitch or pine resins were found in addition to linseed oil. What also draws the attention was the confirmation of pig’s blood in the grounding of the Chinese panels with the forensic DNA fingerprint. It is a tradition that pig’s blood is used to seal the wooden support by whisking the blood and adding chalk or lime and also as a mixture with tile powder to build up foundation layers.Zhang,K.
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Oxidised copper ore bodies may be treated via several processes, with hydrometallurgical processes used to treat oxide ores dominated by copper carbonate minerals such as azurite and malachite, and other soluble minerals such as silicates like chrysocolla, or sulfates such as atacamite and so on. Such oxide ores are usually leached by sulfuric acid, usually in a heap leaching or dump leaching process to liberate the copper minerals into a solution of sulfuric acid laden with copper sulfate in solution. The copper sulfate solution (the pregnant leach solution) is then stripped of copper via a solvent extraction and electrowinning (SX-EW) plant, with the barred (denuded) sulfuric acid recycled back on to the heaps. Alternatively, the copper can be precipitated out of the pregnant solution by contacting it with scrap iron; a process called cementation.
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The mantle was a gift of the city of Paris to the Queen upon her marriage to Carlos, Prince Royal of Portugal in 1886. She is known to have worn it on only two occasions: on 4 July 1892, during the ceremony at Necessidades Palace in which she was presented with the Golden Rose, conferred to her by Pope Leo XIII; and on 21 March 1899, during a gala reception at the Palace of Ajuda to celebrate her son Luís Filipe, Prince Royal's 12th birthday. The mantle has been kept in the National Coach Museum, in Lisbon, since 1936. In 2018, as it was showing evident signs of deterioration (several tears, the silver embroidery had oxidised, the rose-coloured velvet had taken on a brownish tinge), it underwent restoration.
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Map of Laurentia and Baltica during the Devonian period The Paleo-Tethys Ocean opened during the Devonian The Devonian period was a time of great tectonic activity, as Euramerica and Gondwana drew closer together. The continent Euramerica (or Laurussia) was created in the early Devonian by the collision of Laurentia and Baltica, which rotated into the natural dry zone along the Tropic of Capricorn, which is formed as much in Paleozoic times as nowadays by the convergence of two great air-masses, the Hadley cell and the Ferrel cell. In these near-deserts, the Old Red Sandstone sedimentary beds formed, made red by the oxidised iron (hematite) characteristic of drought conditions. Near the equator, the plate of Euramerica and Gondwana were starting to meet, beginning the early stages of the assembling of Pangaea.
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Initially, copper is oxidized to the cuprous ion: (1) Cu → Cu+ \+ e− The cuprous ion reacts with the chloride ion to form the insoluble white colored salt cuprous chloride: (2) Cu+ \+ Cl− → CuCl The cuprous chloride reacts with atmospheric moisture and oxygen to form a green cupric chloride/cupric hydroxide compound and hydrochloric acid: (3) 4 CuCl + 4 H2O + O2 → CuCl2·3 Cu(OH)2 \+ 2 HCl The remaining copper is oxidised by air to the cuprous ion: (4) Cu → Cu+ \+ e− The cuprous ion reacts with the chloride ion in the hydrochloric acid to form the insoluble white colored salt cuprous chloride: (5) Cu+ \+ Cl− → CuCl The reaction then repeats from equation (3). It is the presence of two different white and green salts that lead to the fuzzy green appearance.
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The trophy was finished and presented to the league in September. It was described thus; "measuring 27 inches across by 22 inches deep, the base is a handsome sample of polished rimu, with overlay of contrasting puriri, on which is an ornate centrepiece in oxidised silver depicting an incident of play in the New Zealand v Australia match of 1926". The donators of the trophy even went to the extent of sending the silver piece to England to have it effectively reproduced. The Auckland City Council Parks Committee designated the following of its grounds to the league code: Auckland Domain (2), Outer Domain (1), Victoria Park, Auckland (1), Walker Road (2), Western Springs (1), Grey Lynn Park (1), and 1 additional ground at Grey Lynn to alternate between rugby and league.
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The oxidised chlorophyll a replaces the electrons by photolysis that involves the oxidation of water molecules to oxygen, protons and electrons. Under changing light conditions, the reversible phosphorylation of light harvesting chlorophyll a/b binding proteins (LHCII) represents a system for balancing the excitation energy between the two photosystems. The N-terminus of the chlorophyll a-b binding protein extends into the stroma where it is involved with adhesion of granal membranes and photo-regulated by reversible phosphorylation of its threonine residues. Both these processes are believed to mediate the distribution of excitation energy between photosystems I and II. This family also includes the photosystem II protein PsbS, which plays a role in energy-dependent quenching that increases thermal dissipation of excess absorbed light energy in the photosystem.
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Ice cores containing thin nitrate-rich layers have been analysed to try to reconstruct a history of past solar storms predating reliable observations. This was based on the hypothesis that solar energetic particles would ionize nitrogen, leading to the production of NO and other oxidised nitrogen compounds, which would not be too diluted in the atmosphere before being deposited along with snow. Beginning in 1986, some researchers claimed that data from Greenland ice cores showed evidence of individual solar-proton events, including the Carrington event. More ice core work casts significant doubt on this interpretation, and shows that nitrate spikes are likely not a result of solar energetic particle events but can be due to terrestrial events such as forest fires, and also correlate with other chemical signatures of known forest fire plumes.
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Eight full-time workers helped execute the designs when Maryon joined in 1900, rising to 15 by 1903. Maryon also had the help of his sisters: Edith Maryon designed at least one work for the school, a 1901 relief plaque of Hardwicke Rawnsley, while Mildred Maryon, who the 1901 census listed as living with her sister, worked for a time as an enameller at the school. Both Herbert and Mildred Maryon worked on an oxidised silver and enamel casket that was presented to Princess Louise upon her 1902 visit to the Keswick School; Herbert Maryon was responsible for the design and his sister for the enamelling, with the resulting work being termed "of a character highly creditable to the School" in The Magazine of Art. Strife with colleagues eventually led to Maryon's departure.
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Production from the capping of oxidised minerals, which required mere leaching in sulphuric acid to dissolve the copper and the recovery of the copper by electrolysis was the sole means of production until the 1950s. However their gradual depletion forced the construction of a mill and flotation plant in 1961 to treat the underlying secondary sulphides. These have been steadily expanded until recently the pit was producing over 600,000 tonnes of copper annually, though this has now fallen with the lower grades as the richer secondary mineralisation is also depleted in the three porphyries that make up the orebody. The present mine is a conventional truck and shovel operation, with a large proportion of the ore crushed in-pit and transported by underground conveyors to the mill bins.
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There are at least two species of bats, frugivorous bat (Rousettus leschenaultii) and insectivorous bat (Hipposideros armiger), that retain (or regained) their ability of vitamin C production. Some of these species (including humans) are able to make do with the lower amounts available from their diets by recycling oxidised vitamin C. On a milligram consumed per kilogram of body weight basis, most simian species consume the vitamin in amounts 10 to 20 times higher than what is recommended by governments for humans. This discrepancy constitutes much of the basis of the controversy on current recommended dietary allowances. It is countered by arguments that humans are very good at conserving dietary vitamin C, and are able to maintain blood levels of vitamin C comparable with simians on a far smaller dietary intake, perhaps by recycling oxidized vitamin C.
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On his return to Newcastle, Richardson became a specialist in manufacturing chemistry, taking out a number of patents for processes. In 1840 he began, at Blaydon, near Newcastle, to remove the impurities, consisting chiefly of antimony, from "hard" lead, and thus to convert it into "soft" lead, by means of a current of air driven over the molten metal; the impurities were oxidised, floated to the surface, and were then skimmed off. Practical improvements introduced into the process by George Burnett soon after led to the annual importation of several thousand tons of Spanish hard lead into the Tyne district, where it was purified. John Percy brought forward evidence that Richardson was not the inventor of this process, quoting a letter from James Leathart, and stating that a patent for it was granted to Walter Hall in 1814.
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A misfired black-figure vessel, with reduction satisfactory only in the left part: the area on the right either reduced insufficiently or reoxidised due to insufficient sealing, perhaps as a result of uneven temperature distribution or bad circulation of reducing gases in the kiln. All colours of Greek black-red vase painting are produced by the different concentrations of iron in the clay, and the different degrees to which that iron is oxidised during firing. Iron has the special feature of forming oxides of various colours, including grey Iron(II) oxide (FeO), red Iron(III) oxide (Fe2O3), and deep black magnetite (Fe3O4). Which of these types of oxidation is achieved depends on the availability of oxygen and the temperature of the reactive mix: a high oxygen content encourages the production of Fe2O3, while a lack of it tends to lead to the creation of FeO or Fe3O4.
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However, the greatest research interest has been the role of PON1 in atherosclerosis, where, because of its ability to remove harmful oxidised-lipids, PON1 protects against the development of atherosclerosis Oxidized polyunsaturated fatty acids (notably in oxidized low-density lipoprotein) form lactone-like structures that are PON substrates. PON1 also protects against bacterial infection by destroying the bacterial signalling molecules that cause gram negative bacteria to invade human tissue and form colonies, thus PON1 contributes to the bodies innate immunity Recently it has been suggested that PON1 has a role in healthy aging, however, the mechanism is currently unknown PON1 activity is low in infants compared to adults. A study of Mexican-American children showed that PON1 activity increased 3.5 times between birth and age seven. An association between PON1 gene polymorphism and susceptibility to Parkinson's disease was not found in a Chinese population.
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Crystal Palace concert platform and lake - Ian Ritchie Architects, 1997 In 1996 an architectural competition was by held by London Borough of Bromley and Arts Council England, to design a new permanent stage in the park. Ian Ritchie Architects won with a proposal for a “simple structure causing minimal disturbance” to the rich and complex Paxton landscape. The sculptural form was inspired by artists like Richard Serra and architects like John Winter in its use of a single material and a continuous surface, namely the self-weathering pre-rusted Corten Steel; it was of the first public buildings in the UK to use the material for external cladding. The outward appearance of the deep red oxidised steel drew inspiration from the earthy colours of the soil and reflections of the sky in the ornamental lake in front of the stage area, aiming to produce a greater harmony between structure and the beauty of surrounding landscape.
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Unusual for proteins, this enzyme crystallizes when dialysed against distilled water. More so, the enzyme purifies as a consequence of crystallization, making cycles of crystallization an effective final purification step. Much like catalase, the reaction of cytochrome c peroxidase proceeds through a three-step process, forming first a Compound I and then a Compound II intermediate: : CCP + ROOH → Compound I + ROH + H2O : CCP-compound I + e− \+ H+ → Compound II : Compound II + e− \+ H+ → CCP CCP-catalyzed redox cycle CCP in the resting state has a ferric heme, and, after the addition of two oxidizing equivalents from a hydroperoxide (usually hydrogen peroxide), it becomes oxidised to a formal oxidation state of +5 (FeV, commonly referred to as ferryl heme. However, both low-temperature magnetic susceptibility measurements and Mössbauer spectroscopy show that the iron in Compound I of CCP is a +4 ferryl iron, with the second oxidising equivalent existing as a long-lived free-radical on the side-chain of the tryptophan residue (Trp-191).
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MIA is composed of two main essential cysteine-rich proteins; Mia40 and Erv1. Mia40 is also referred to as Tim40 in yeast and deficiency of Mia40 has been reported to affect import of the small Tims. Mia40 is anchored to the mitochondrial inner membrane via an N-terminal hydrophobic segment, exposing a large domain to the intermembrane space. It contains 6 conserved cysteine residues, which allow the binding of incoming Tim precursor proteins.Chacinska, A., Pfannschimdt, S., Wiedemann, N., Kozjak, V., Sanjuán Szklarz, LK., Schulze-Specking, A., Truscott, KN., Guiard, B., Meisinger, C., Pfanner, N.(2004) Essential role of Mia40 in import and assembly of intermembrane space proteins. EMBO J 23: 3735-3746. Following import of small Tim proteins into the intermembrane space Mia40 interacts with small Tim proteins via disulfide bonds. Following isomerisation of the disulfide bridge, the polypeptide is released. Mia40 which is now in reduced state, is then oxidised by Erv1.Tokatlidis, K. (2005) A disulphide relay system in mitochondria.
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Other variations focus on specialisms within the profession; for example Blacksmith, from those who worked predominantly with iron, Whitesmith, from those who worked with tin (and the more obvious Tinsmith), Brownsmith and Redsmith, from those who worked with copper (Coppersmith and Greensmith; copper is green when oxidised), Silversmith and Goldsmith – and those based on the goods produced, such as Hammersmith, Bladesmith, Naismith (nail-smith), Arrowsmith which in turn was shortened to Arsmith, or Shoesmith (referring to horseshoes). Sixsmith is variant spelling of a sickle- or scythe-smith. Wildsmith in turn is a corruption of wheelsmith The patronymic practice of attaching son to the end of a name to indicate that the bearer is the child of the original holder has also led to the surnames Smithson and Smisson. Historically, "Smitty" has been a common nickname given to someone with the surname, Smith; in some instances, this usage has passed into "Smitty" being used as a surname itself.
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The metabolism of the tobacco smoke procarcinogen benzo[a]pyrene involves three distinct steps - the introduction of an epoxide group in the 7,8-position, its hydration to a vicinal diol and the introduction of an epoxide in the 9,10-position. In the first step, a cytochrome P450 1A1 (CYP1A1) catalysed oxidation produces several products including (+)-benzo[a]pyrene-7,8-epoxide. The enzyme epoxide hydrolase, then hydrates the epoxide ring to yield the vicinal diol (−)-benzo[a]pyrene-7,8-dihydrodiol, which is then oxidised by cytochrome P450 oxidase again forming the mutagen and carcinogen (+)-benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide. This diol epoxide covalently binds to DNA by a ring-opening to alkylate the nucleobase forming a distorted structure, as shown at right, with intercalation of a pyrene polycyclic aromatic hydrocarbon moiety between the base pairs favouring π-stacking; these distortions have been confirmed by X-ray crystallographic and nuclear magnetic resonance structure studies.
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The ion-selective membrane (B) allows the counterion Na+ to freely flow across, but prevents anions such as hydroxide (OH−) and chloride from diffusing across. At the cathode (C), water is reduced to hydroxide and hydrogen gas. The net process is the electrolysis of an aqueous solution of NaCl into industrially useful products sodium hydroxide (NaOH) and chlorine gas. Saturated brine is passed into the first chamber of the cell where the chloride ions are oxidised at the anode, losing electrons to become chlorine gas (A in figure): :2Cl− → + 2e− At the cathode, positive hydrogen ions pulled from water molecules are reduced by the electrons provided by the electrolytic current, to hydrogen gas, releasing hydroxide ions into the solution (C in figure): :2 + 2e− → H2 \+ 2OH− The ion- permeable ion exchange membrane at the center of the cell allows the sodium ions (Na+) to pass to the second chamber where they react with the hydroxide ions to produce caustic soda (NaOH) (B in figure).
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In a zinc–carbon dry cell, the outer zinc container is the negatively charged terminal. The zinc is oxidised by the charge carrier, chloride (Cl−), via the following half-reactions: Anode (oxidation reaction, marked −) : Zn + 2 Cl− → ZnCl2 \+ 2 e− Cathode (reduction reaction, marked +) : 2 MnO2 \+ 2 NH4Cl + H2O + 2 e− → Mn2O3 \+ 2 NH4OH + 2 Cl− Other side reactions are possible, but the overall reaction in a zinc–carbon cell can be represented as : Zn + 2 MnO2 \+ 2 NH4Cl + H2O → ZnCl2 \+ Mn2O3 \+ 2 NH4OH If zinc chloride is substituted for ammonium chloride as the electrolyte, the anode reaction remains the same: : Zn + 2 Cl− → ZnCl2 \+ 2 e− and the cathode reaction produces zinc hydroxide instead of ammonium hydroxide: : 2 MnO2 \+ ZnCl2 \+ H2O + 2 e− → Mn2O3 \+ Zn(OH)2 \+ 2 Cl− giving the overall reaction : Zn + 2 MnO2 \+ H2O → Mn2O3 \+ Zn(OH)2 The battery has an electromotive force (e.m.f.) of about 1.5 V. The approximate nature of the e.m.f is related to the complexity of the cathode reaction.
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Original variant 1938 to 1943 of the Jubilee Medal "XX Years of the Workers' and Peasants' Red Army" The Jubilee Medal "XX Years of the Workers' and Peasants' Red Army" is a 32 mm in diameter oxidised silver matte finished circular medal with a polished 2.5 mm rim. On the obverse, a large red enamelled five pointed star with a silvered edge, the tip of each point reaching the medal's edge; at the bottom sitting on the rim, in deep relief, the prominent 8 mm high gilded Roman numeral "XX" going up between the star's lower rays to superimpose it over 4 mm. On the reverse, a 25 mm high relief image of a Red Army soldier clad in the winter uniform of the Red Guard and firing a rifle, at the lower right side of the soldier, the dates "1918-1938". From its establishment in 1938 to 1943, the medal was secured by a ring through the medal suspension loop to a small rectangular mount covered by a red silk moiré ribbon.
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The work remained with the descendants of Pedro de Sousa Holstein, 1st Duke of Palmela, who bought it in 1845 from Sequeira's daughter Mariana Benedita, along with the four other paintings that comprise the Palmela Series, until 2016. A public fundraising campaign called "Vamos pôr o Sequeira no Lugar Certo" (Let's put the Sequeira in the right place), launched in October 2015, counted with the small contributions of thousands of private citizens, institutions, companies, schools, local governments, and even President Rebelo de Sousa; the largest contribution, of 200 thousand euros, was made by the Aga Khan Foundation in the person of Prince Amyn Aga Khan. The campaign raised more than 745 thousand euros, surpassing the 600 thousand the owners asked for — the leftover revenue was set aside to buy another painting, in 2018: a 15th- century Annunciation by Álvaro Pires de Évora, sold in a Sotheby's auction in New York. The painting then underwent restoration by the Museum's Department for Conservation and Restoration, for two months: even though it was in very good state of preservation, restorers removed applications of old oxidised varnish that gave the painting a yellowish hue and concealed some detail, as well as minor overpainting.
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As such, iodide is the best leaving group among the halogens, to such an extent that many organoiodine compounds turn yellow when stored over time due to decomposition into elemental iodine; as such, they are commonly used in organic synthesis, because of the easy formation and cleavage of the C–I bond. They are also significantly denser than the other organohalogen compounds thanks to the high atomic weight of iodine. A few organic oxidising agents like the iodanes contain iodine in a higher oxidation state than −1, such as 2-iodoxybenzoic acid, a common reagent for the oxidation of alcohols to aldehydes, and iodobenzene dichloride (PhICl2), used for the selective chlorination of alkenes and alkynes. One of the more well-known uses of organoiodine compounds is the so-called iodoform test, where iodoform (CHI3) is produced by the exhaustive iodination of a methyl ketone (or another compound capable of being oxidised to a methyl ketone), as follows: :450px Some drawbacks of using organoiodine compounds as compared to organochlorine or organobromine compounds is the greater expense and toxicity of the iodine derivatives, since iodine is expensive and organoiodine compounds are stronger alkylating agents.
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Magnesium-protoporphyrin IX monomethyl ester (oxidative) cyclase (), is an enzyme with systematic name magnesium-protoporphyrin-IX 13-monomethyl ester, ferredoxin:oxygen oxidoreductase (hydroxylating). In plants this enzyme catalyses the following overall chemical reaction The chlorin ring system forms as the esterified propionate sidechain is cyclised on to the porphyrin ring of protoporphyrin IX to form divinylprotochlorophyllide : magnesium- protoporphyrin IX 13-monomethyl ester + 3 NADPH + 3 H+ \+ 3 O2 \rightleftharpoons divinylprotochlorophyllide + 3 NADP+ \+ 5 H2O (overall reaction) Recent evidence shows that the necessary electrons which cycle the enzyme from oxidised to reduced form come from ferredoxin. In green tissue, ferredoxin can receive these electrons directly from photosystem I so that NADPH need not be involved. However, in the dark, ferredoxin can also be reduced via Ferredoxin—NADP(+) reductase, allowing the reaction to proceed in that case. It is therefore more accurate to show the individual steps as follows: :(1a) magnesium-protoporphyrin IX 13-monomethyl ester + 2 reduced ferredoxin + O2 \rightleftharpoons 131-hydroxy-magnesium-protoporphyrin IX 13-monomethyl ester + H2O :(1b) 131-hydroxy-magnesium-protoporphyrin IX 13-monomethyl ester + 2 reduced ferredoxin + O2 \rightleftharpoons 131-oxo- magnesium-protoporphyrin IX 13-monomethyl ester + 2 H2O :(1c) 131-oxo- magnesium-protoporphyrin IX 13-monomethyl ester + 2 reduced ferredoxin + O2 \rightleftharpoons divinylprotochlorophyllide + 2 H2O This enzyme requires Fe(II) for activity.
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