Destruction Kinetics of 2,4 Dichlorophenol Aqueous Solutions in an Atmospheric Pressure Dielectric Barrier Discharge in Oxygen

The processes of degradation of 2,4-dichlorophenol (2,4-DCP) aqueous solutions under the action of atmospheric pressure of DBD in oxygen were studied. The degradation of 2,4-DCP proceeds efficiently, the degree of decomposition reaching 100%. The degradation kinetics of 2,4-DCP obeys a formal first-order kinetic law on concentration of 2,4-DCP. The effective rate constants depend weakly on the experimental conditions and are equal to ~ 2 s^?1. Based on experimental data, the energy efficiency of 2,4-DCP decomposition was determined to be in the range of 0.039–0.173 molecules per 100 eV depending on the experimental conditions. The composition of the products was studied by gas chromatography, chromatography-mass spectrometry, UV/visible spectroscopy, fluorescent methods and some chemical methods. The main decomposition products present in the solution were found to be carboxylic acids, aldehydes and chloride ions, whereas carbon dioxide and molecular chlorine appear in the gas. The results obtained are compared with similar data from other advanced oxidation processes (AOP’s) methods.     

Synthesis of tritium-labeled PAM-43

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Synthesis and electrochemical study of 2-carbamoyl-4,5-dihydro-1,3,4-thiadiazole-containing ligands and their complexes with Cuii, Coii and Niii

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Dioximes of 1,6-heptanediones from acetylene and ketones: only three atom-economic steps

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Three-dimensional grids based on graphene oxide and 3,3’,4,4’-tetraaminodiphenyl oxide for supercapacitor electrodes

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Polyacrylonitrile molecular weight effect on the structural and magnetic properties of metal–carbon nanomaterial

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Synthesis,conformational preferences in gas and solution,and molecular gear rotation in 1-(dimethylamino)-1-phenyl-1-silacyclohexane by gas phase electron diffraction (GED), LT NMR and theoretical calculations

1-(Dimethylamino)-1-phenyl-1-silacyclohexane 1, was synthesized, and its molecular structure and conformational properties studied by gas-phase electron diffraction (GED), low temperature ¹³C NMR spectroscopy and quantum-chemical calculations. The predominance of the 1-Ph_ax conformer (1-Ph_eq:1-Ph_ax ratio of 20:80%, ΔG°(317?K)?=??0.87?kcal/mol) in the gas phase is close to the theoretically estimated conformational equilibrium. In solution, low temperature NMR spectroscopy showed analyzable decoalescence of C_ipso and C(1,5) carbon signals in ¹³C NMR spectra at 103?K. Opposite to the gas state in the freon solution employed (CD₂Cl₂/CHFCl₂/CHFCl₂?=?1:1:3), which is still liquid at 100?K, the 1-Ph_eq conformer was found to be the preferred one [(1-Ph_eq: 1-Ph_ax?=?77%: 23%, K?=?77/23?=?2.8; ?ΔG°?=??RT ln K (at 103?K)?=?0.44?±?0.1?kcal/mol]. When comparing 1 with 1-phenyl-1-(X)silacylohexanes (X?=?H, Me, OMe, F, Cl), studied so far, the trend of predominance of the Ph_ax conformer in the gas phase and of the Ph_eq conformer in solution is confirmed.     

A new approach to the synthesis of lactams of muramic,isomuramic and normuramic acids via intramolecular O-alkylation: Stereochemical features of the intramolecular nucleophilic substitution

The title compounds were synthesized from the selectively protected N-acylated d-glucosamine derivatives, containing α-halo carboxylic acid moieties, via intramolecular 3-O-alkylation. It was found that if the starting compound contains asymmetric electrophilic center, isomuramic acid derivatives were mainly formed, regardless of the configuration of the electrophilic carbon atom. An explanation for the observed stereochemical results was proposed on the basis of the analysis of steric interactions in the molecules of the starting compounds, as well as using the concept of anchimeric assistance. It was shown that N-acetylation of the obtained lactam derivatives and subsequent methanolysis under mild conditions led to the selective cleavage of δ-lactam ring resulting in the formation of the corresponding ester derivatives of N-acetylmuramic acid or its analogues in high yields.