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Showing 1 to 20 of 697 for “"Dimethyl"”.
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Large-scale production of oxymethylene dimethyl ethers
Oxymethylene dimethyl ethers (OME) show promising solubility and combustion properties for applications in various chemical processes and sectors. They enable clean and quasi soot-free combustion, which can strongly reduce NOx emissions. Besides reducing local emissions, OME can strongly reduce CO2 …
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A Self -Healing Poly(dimethyl Siloxane) Elastomer
The self-healing performance of the elastomer is also investigated under torsional fatigue loading. The microcapsule-based self-healing PDMS is capable of recovering a significant portion of the original torsional stiffness and retards dynamic crack growth rate. Depending on the matrix material, a …
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Characterization of Yeast 18S rRNA Dimethyl Transferase, Dim1p
… One conserved group of modifications is the dimethylation of two adjacent adenosines at the 3´ end of the small subunit rRNA which is ubiquitously carried out by the Dim1/KsgA methyltransferase family. Although dimethylation and KsgA are dispensable for survival in bacteria, the eukaryotic …
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Nucleophilic displacement reactions of some carbohydrates in dimethyl sulphoxide
… reactions with sodium hydrogen carbonate in dimethyl sulphoxide. Similar reactions are known to convert acylic primary sulphonates and iodides to aldehydes but the sugar derivatives were observed to yield different products. Detosylation of the sugars to give the corresponding alcohols was …
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Nucleophilic displacement reactions of some carbohydrates in dimethyl sulphoxide
… reactions with sodium hydrogen carbonate in dimethyl sulphoxide. Similar reactions are known to convert acylic primary sulphonates and iodides to aldehydes but the sugar derivatives were observed to yield different products. Detosylation of the sugars to give the corresponding alcohols was …
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Electromechanical Characterization of Poly(Dimethyl Siloxane) Based Electroactive Polymers
… polar cyano phenyl (CN) groups on poly (dimethyl siloxane) (PDMS) and 2) to characterize the electromechanical properties of the resulting CN-PDMS blend as an electroactive actuator. Materials responding to an external stimulus are referred to as electroactive materials. There are several …
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Scaling down direct dimethyl ether synthesis for biogas conversion
The feasibility of direct DME synthesis from biogas conversion as a small scale energy storage system was studied. Anaerobic digestion (AD) of grass silage was used as a feedstock for production of biogas and it was found that grass silage has high affinity for methane enriched biogas. A …
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Diffusion of dimethyl sulfoxide in aqueous mixtures and polyelectrolyte gels
<p>Diffusion coefficients, D<sub>BULK</sub>, of dimethyl sulfoxide (DMSO) were measured in free (“bulk”) aqueous mixtures by the capillary method using sulfur-35 labeled DMSO. The value of D<sub>BULK</sub> was found to pass through a minimum at approximately 33 mole percent DMSO as DMSO …
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The Development of Microfluidic Devices Fabricated From Poly(dimethyl) Siloxane
… fabrication of microfluidic devices using poly(dimethyl) siloxane (PDMS). Fabrication involved lithographic and ""soft"" lithographic techniques. Capillary electrophoretic separation ""chips"" as well as a series of patterns for surface functionalization were demonstrated in PDMS. PDMS proved to …
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Electron paramagnetic resonance analysis of dimethyl amidogen in polycrystalline tetramethyl tetrazene.
… species has been identified as the free radical dimethyl amidogen. The hyperfine coupling tensors were assigned on the basis of a polycrystalline line shape analysis. The radical exhibits axial symmetry with the parallel components of the tensors greater than the perpendicular components. The …
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The synthesis and characterisation of novel long chain dimethyl siloxane surfactants.
… has been replaced by a long, hydrophobic polydimethylsiloxane chain. Polydimethylsiloxanes are low melting materials (glass transition at ca -120°C) with very flexible chains, hence surfactants based on them might be readily soluble in water. This project involves chemical attachment of …
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The attempted synthesis of 4,4-dimethyl-3-dimethylamino-2,6-cyclohexanedione carboxamide
<p>The use of boron-containing amines for the amino alkylation of amides has been investigated in our laboratories with the aim of preparing compounds which could be used in neutron capture therapy. The purpose of this procedure is to achieve selective irradiation of a neoplactic growth by inducing …
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Poly (2,6-dimethyl-1,4-phenylene oxide) hollow fibres for gas separation.
… CO2/CH 4 gas separation performance of poly(2,6-dimethyl 1,4-phenylene oxide) (PPO). Hollow fibres were prepared by the dry-wet spinning method from solutions of PPO in trichloroethylene using the non-solvent methanol as the bore liquid and for the gelation bath. The variables studied were the …
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Development, uncertainty quantification, and reduction of a dimethyl sulfide oxidation mechanism
Dimethyl sulfide (DMS), arising from phytoplankton, is the largest natural source of sulfur in the atmosphere. The oxidation products of DMS, such as methanesulfonic acid and sulfuric acid, can contribute to cloud condensation nuclei. Studying the oxidation mechanism of DMS will help improve our …
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Dimethyl N-Aryl phosphoramidates : structural effects on bonding and solvolytic reactivity
… hydrolysis of a number of ring alkyl substituted dimethyl N-aryl phosphoramidates, (MeO)2P(0)NHAr, has been studied by measuring the rates of hyd~olysis with the aid of a UV spectrophotometer. These rates have been correlated with the pKa values of the corresponding ani I inium iOhs and the slope …
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NMR study of peptide derivatives in cryoprotective media and dimethyl sulfoxide
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1997.
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Hafnium Dioxide Nanoparticle Thin Film Morphology and Reactivity with Dimethyl Methylphosphonate
… Once characterized, they are exposed to dimethyl methylphosphonate and the surface reaction is analyzed by reflection-absorption infrared spectroscopy.
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Catalytic Conversion of Glycerol to Glycerol Carbonate Utilizing CO₂ and Dimethyl Carbonate
… CO2, an abundant, non-toxic greenhouse gas, and dimethyl carbonate (DMC), which yields more glycerol carbonate. The catalysts were prepared by co-precipitation method, and characterized by using XPS, FT-IR, XRD, TGA, SEM, and CO2-TPD techniques. Firstly, metal oxide catalysts of Al2O3, CaO, and …
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