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Showing 1 to 20 of 151 for “"Nitrile"”.
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High Performance Materials Containing Nitrile Groups
… ′-Bis(3,4-dicyanophenoxy)biphenyl(biphenoxyphthalonitrile). A 700 g mol-1 novolac oligomer was cured with relatively low concentrations of this reagent (~20 wt %) into high Tg (~190 °C) networks. The curing reaction was attrubuted to nucleophilic attack of the phenolic hydroxyl on the nitrile …
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The crystal structure of a mutant nitrile hydratase
Nitrile hydratases can be used as industrial biocatalysts. They catalyze the conversion of nitriles to their corresponding amides. These industrial biocatalysts have recently gained attention due to the economic production of industrial commodities such as acrylamide and nicotinamide (Thomas et …
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Catalytic Mechanism and Maturation of the Metalloenzyme Nitrile Hydratase
<p>Nitrile hydratases are metalloenzymes that catalyze the hydration of nitriles to their corresponding amides in a specific manner at ambient pressures and temperatures at neutral pH. Traditional industrial methods require high temperature and pressure, extreme pH, and heavy metals. NHases are …
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Investigating the Biochemical and Catalytic Properties of Nitrile Hydratases
… is typically achieved by the hydration of nitrile compounds under acidic or basic conditions, high temperatures, and copper catalysts. However, the use of such chemical methods leads to the generation of unwanted by-products and toxic wastes, in addition to low product yields and high …
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Mechanistic studies of nitrile hydratases and their activator proteins
Nitrile hydratases (NHases) are iron- or cobalt-containing metalloenzymes with a hexadentate active site characterized by a highly conserved CXXCSC motif on the α subunit. Two of the active site cysteine residues undergo post-translational oxidation to sulfenic and sulfinic acid moieties. Both the …
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The structure, function and engineering of a thermostable nitrile hydratase
Nitrile hydratases (NHases) are enzymes that catalyse the conversion of organocyanides to amides via a non-hydrolytic hydration reaction. They are industrially relevant enzymes, currently used in the manufacture of nicotinamide and acrylamide. The target of this study belongs to the thermophilic …
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Screening for novel cold-adapted nitrile hydratases in Antarctic metagenornic libraries
Nitrile hydratases (NHase) catalyse the hydrolysis of nitriles to their corresponding amides, the first step in the nitrile degradation pathway. The second step is the conversion of the amide to a carboxylic acid, catalysed by an amidase. The NHases published to date have been isolated from …
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Isoxazole Linked siRNA Cholesterol Conjugates by Catalyst Free Nitrile Oxide/Alkyne Cycloadditions
… dipolar cycloaddition chemistry of nitrones and nitrile oxides with alkene and alkyne dipolarophiles Chapter 2 presents the somewhat disappointing findings on the cycloaddition reactions of maleimides. Reactions with “simple” maleimides suffered from poor yield and/or poor diastereoselectivity, …
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The synthesis and sensing capabilities of new amide, urea and nitrile calix4arenes
… Functional groups include ureas, amides and nitriles, targeting cations and anions as guest species. The main methods used for transducing complexation events are potentiometry and fluorescence. The various hosts and guests investigated attempt to reflect the versatility and ongoing evolution …
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The relationship between structure and thermostability of a nitrile hydratase from Goebacillus pallidus RAPc8
Nitrile hydratases (NHases) are very important biocatalysts for the enzymatic conversion of nitriles to industrially important amides such as acrylamide and nicotinamide. An “ideal” NHase should fulfil several essential criteria including, high substrate conversion rates, being able to tolerate …
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Calculation of Electron Collision Cross Sections in Fluorinated Nitrile (C4F7N) and its Dissociation Fragments
C4F7N has received considerable attention in recent years as an insulating gas due to its higher dielectric strength and low global warming potential relative to SF6. To evaluate the behavior of this novel gas during high-voltage gaseous discharges, plasma models require electron-neutral collision …
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Genetic characterization of Rhodococcus rhodochrous ATCC BAA-870 with emphasis on nitrile hydrolysing enzymes
… isolated on selective media for enrichment of nitrile hydrolysing bacteria. The organism was found to have a wide substrate range, with activity against aliphatics, aromatics, and aryl aliphatics, and enantioselectivity towards beta substituted nitriles and beta amino nitriles, compounds that …
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Synthesis And Biological Evaluation Of Nitrile-Based Inhibitors Of Cysteine Proteases Caged With Ruthenium Complexes
… developing ruthenium-based photocages for caging nitrile-based cysteine protease inhibitors. Four research areas pertaining to this dissertation, i) metals in medicine, ii) photocages in biological applications, iii) photodynamic therapy and iv) cysteine cathepsin proteases were briefly surveyed …
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Investigation of the determinants of thermal stability of the nitrile hydratase from Geobacillus pallidus RAPc8
… to enhance their application in industry. The nitrile hydratases group of enzymes catalyse the hydrolysis of nitriles to amides using an exothermic catalytic mechanism. Understanding and applying specific amino acid residue mutations at specific regions in protein structures has been important …
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Synthesis and Characterization of Nitrile Containing Polysiloxanes and Their Corresponding Networks as Aircraft Sealant Materials
Polysiloxane networks have excellent oxidative and good UV environmental stability, flexibility at low temperatures, and thermal stability at higher temperatures. This wide service temperature range makes these materials a candidate class of materials for high performance adhesives and sealants, …
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Aqueous Organometallic Catalysis: Nitrile Hydration Catalyzed by Ruthenium(II) 1,3,5-triaza-7-phosphaadamantane (PTA) Derived Complexes
… ligands for the application of aqueous phase nitrile hydration. A series of PTA and PTA derivatives were characterized via solid-state NMR (SSNMR) and compared to their corresponding solution NMR spectra. Highly water-soluble β-phosphino alcohols (PTA-CR1R2OH) were prepared by reacting …
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Synthesis and Coordination Chemistry of Novel Water Soluble Diphosphines: Application to Ruthenium Catalyzed Aqueous Nitrile Hydration
… identified as catalytically active toward benzonitrile hydration. Isolated air-stable, water-soluble ruthenium arene complexes were further investigated for a variety of nitriles featuring methoxy, nitro, pyridyl, benzyl, and alkyl functional groups. Conversion of these nitriles to the …
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Preparation of Nitrile Containing Siloxane Triblock COpolymers and Their APplication As Stabilizers For Siloxane Magnetic Fluids
Nitrile containing siloxane block copolymers were developed as stabilizers for siloxane magnetic fluids. The siloxane magnetic fluids have been recently proposed as internal tamponades for retinal detachment surgery. PDMS-b-PCPMS-b-PDMSs (PDMS = polydimethylsiloxane, PCPMS = …
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A spectroscopic study of halogenated and nitrile substituted hydrocarbons in low temperature inert matrices and other phases
Infrared and Raman spectra of halogenated and nitrile substituted hydrocarbons have been studied in various phases including temperatures as low as 8 K by isolation in matrices of solid argon or krypton.<br/><br/>In the compounds :-<br/><br/>CH 2 =CH 2 CH 2 =CHD CH 2 =CH(CH 2 ) n -X<br/>where n= …
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