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In this article, a graphite felt electrode was modified by NS double‐element and NB double‐element codoping. The surface morphology, crystal structure, element content, and surface chemical state of the modified electrode were characterized by scanning electron microscopy, X‐ray powder diffraction (XRD), Raman spectroscopy, and X‐ray photoelectron spectroscopy. The electrochemical performance of the modified electrode was evaluated by cyclic voltammetry, electrochemical impedance spectra, and a single cell. The results show that nitrogen (N) and boron (B) double‐element codoping can enhance the catalytic activity of graphite felt and create abundant defect sites, which increases the electrocatalytic activity by approximately a factor of 2. The reason why the doped graphite felt can obtain higher electrocatalytic activity may be related to the synergy between N and B atoms, especially the synergy between pyridine‐N and BC3, and the resistance of the first charge transfer reaction of 1,8‐dihydroxyanthraquinone on the doped graphite felt electrode is then reduced. [ABSTRACT FROM AUTHOR]

An aroma-producing strain MG6 with aroma production was isolated from the surface of sunny rose grape. The strain was identified and the characteristic aroma components of its fermentation broth were analyzed. Then the tobacco flavor was prepared by the strain and the aroma evaluation of cigarette was carried out. The results showed that the strain was Pichia terricola. Compared with the control group, the main characteristic aroma components such as ketones, alcohols, esters, phenols and olefins in the fermentation broth of the strain were significantly increased, and the total contents of megastigmatrien-3-one, dihydrokiwifruit lactone and neophytadiene were increased in different degrees, which were particularly important for improving the aroma quality of tobacco. When the added amount of tobacco flavoring was 0. 05%, the quality and amount of aroma were improved, the irritation was reduced, and the overall sensory quality was improved. [ABSTRACT FROM AUTHOR]

To investigate the key burnt-sweet, creamy and bean aroma components in mainstream cigarette smoke and their distribution characteristics as well as sensory contributions, and to guide the flavoring of tobacco products effectively, the tobacco and tobacco smoke components listed in The Chemical Components of Tobacco and Tobacco Smoke were systematically evaluated. The components with burnt-sweet, creamy and bean aroma characteristics were screened and identified, and their distribution characteristics in total particulate matter (TPM) of mainstream smoke from 9 cigarette brands were determined by GC/MS. The contributions of those components to the burnt-sweet, creamy and bean aroma notes in mainstream cigarette smoke were assessed based on their odor activity values (OAVs). The results showed that: 1) There were 18 components with burnt-sweet aroma note, 15 with creamy aroma note and 5 with bean aroma note in mainstream cigarette smoke. 2) In the mainstream smoke of different types of cigarettes, the releases of hydroxyacetone, 2, 3-butanedione, methyl cyclopentenolone and 4-hydroxy-2,5-dimethyl-3(2H)-furanone were higher than those of the other components. 3) The total releases of the above 38 components in mainstream smoke of blended type cigarettes were remarkably lower than those of Virginia type cigarettes. 4) The contribution of burnt-sweet aroma note to mainstream cigarette smoke was more significant than that of creamy and bean aroma notes. The key components with burnt-sweet aroma note were 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 3,4-dimethyl-1, 2-cyclopentadione, methyl cyclopentenolone and 3-ethyl-2-hydroxy-2-cyclopenten-1-one, those with creamy aroma note were 2,3-butanedione, ethyl vanillin and vanillin, and those with bean aroma note were 6-methylcoumarin and dihydrocoumarin. [ABSTRACT FROM AUTHOR]