Determination of Catechol by Cetyltrimethylammonium Bromide Functionalized Graphene Modified Electrode

A simple and sensitive electrochemical sensor was prepared by using electrodeposition of the cetyltrimethylammonium Bromide (CTMAB ) functionalized Graphene (GR) on the glassy carbon electrode (GCE) to determine Catechol (CC) in water. The performance of the CTMAB functionalized GR sensor was studied and the analysis conditions of the CC were optimized. The experimental results showed that, compared with bare GCE, the redox peak current of CC on the modified electrode was obviously enhanced. Under the optimized conditions, the oxidation and reduction peak current all showed a good linear relationship with the concentration of CC from 5μmol/L to 1000 μmol/L. The detection limit of oxidation peak is 2.92 μmol/L, and that of reduction peak is 2.44 μmol/L. The recovery was founded to be in the range of 92.70 %~101.80 %. Moreover, the sensor could be used for the determination of CC in real samples with satisfactory results. And the mechanism of the sensitization of CC detected by CTMAB-GR modified GCE was discussed preliminarily

Determination of Catechol by Cetyltrimethylammonium Bromide Functionalized Graphene Modified Electrode

A simple and sensitive electrochemical sensor was prepared by using electrodeposition of the cetyltrimethylammonium Bromide (CTMAB ) functionalized Graphene (GR) on the glassy carbon electrode (GCE) to determine Catechol (CC) in water. The performance of the CTMAB functionalized GR sensor was studied and the analysis conditions of the CC were optimized. The experimental results showed that, compared with bare GCE, the redox peak current of CC on the modified electrode was obviously enhanced. Under the optimized conditions, the oxidation and reduction peak current all showed a good linear relationship with the concentration of CC from 5μmol/L to 1000 μmol/L. The detection limit of oxidation peak is 2.92 μmol/L, and that of reduction peak is 2.44 μmol/L. The recovery was founded to be in the range of 92.70 %~101.80 %. Moreover, the sensor could be used for the determination of CC in real samples with satisfactory results. And the mechanism of the sensitization of CC detected by CTMAB-GR modified GCE was discussed preliminarily

Determination of Catechol by Cetyltrimethylammonium Bromide Functionalized Graphene Modified Electrode

A simple and sensitive electrochemical sensor was prepared by using electrodeposition of the cetyltrimethylammonium Bromide (CTMAB ) functionalized Graphene (GR) on the glassy carbon electrode (GCE) to determine Catechol (CC) in water. The performance of the CTMAB functionalized GR sensor was studied and the analysis conditions of the CC were optimized. The experimental results showed that, compared with bare GCE, the redox peak current of CC on the modified electrode was obviously enhanced. Under the optimized conditions, the oxidation and reduction peak current all showed a good linear relationship with the concentration of CC from 5μmol/L to 1000 μmol/L. The detection limit of oxidation peak is 2.92 μmol/L, and that of reduction peak is 2.44 μmol/L. The recovery was founded to be in the range of 92.70 %~101.80 %. Moreover, the sensor could be used for the determination of CC in real samples with satisfactory results. And the mechanism of the sensitization of CC detected by CTMAB-GR modified GCE was discussed preliminarily

Design, synthesis and characterization of new organic semi-conductors for photovoltaics

Les cellules photovoltaïques organiques sont une technologie prometteuse pour répondre aux besoins futurs en énergie. Elles présentent de faibles coûts de production, peuvent être réalisées sur substrats flexibles et s'intègrent dans des dispositifs légers. Une voie d'amélioration du rendement de photoconversion est la conception de nouvelles molécules actives présentant des propriétés structurales optimisées. Le présent travail s'inscrit dans cette dynamique: sur la base de calculs utilisant la théorie de la fonctionnelle de la densité, de nouveaux semiconducteurs organiques ont été conçus puis synthétisés. Pour cela, des techniques de synthèses les plus économiques et les moins polluantes possible ont été mises en œuvre. Ainsi, le couplage du benzothiadiazole avec le thiophène carboxhaldéhyde par hétéroarylation directe sans additif ni ligand est utilisé avec succès pour la première fois selon des techniques de chimie verte. Cinq molécules sont ainsi isolées en seulement deux étapes. L'étude de leurs propriétés optiques et électroniques par différentes techniques spectroscopiques (UV/vis, fluorescence) et par électrochimie, de leurs propriétés thermiques, et de leur aptitude à s'auto-organiser ont permis de révéler leur aptitude prometteuse pour une utilisation en photovoltaïque organique. Une série de molécules dérivées du fragment dithiénosilole (DTS) ont été également étudiées par calculs de DFT. Les résultats obtenus montrent que ces dérivés présentent des largeurs de bande interdite très faibles, ce qui constitue un atout pour leur utilisation en cellule photovoltaïque. Ces résultats ont par conséquent motivé leur synthèse. Enfin, un travail purement théorique a été réalisé sur des molécules dérivées des subphthalocyanines de bore. Les calculs effectués révèlent des propriétés électroniques originales pour ces nouveaux matériaux qui devraient mener à des performances intéressantes pour le photovoltaïque organique, ouvrant ainsi la voie vers des matériaux innovants et prometteurs.Organic solar cells appear as a promising technology to meet future energy requirements, owing to their low production costs, their great flexibility and their ability to be integrated into light devices. Currently, they exhibit modest performances in photoconversion, thus new active molecules with optimized structural properties need to be developed. This work comes in that aim: on the basis of theoretical calculations with density functional theory, new organic semiconductors have been designed and synthesized. For this, the more economical and cleaner syntheses techniques have been employed. Thus, the coupling of the benzothiadiazole with thiophene carboxhaldehyde via direct heteroarylation without additive nor ligand is performed with success for the first time. According to green chemistry techniques, five molecules are thus isolated in only two steps. The study of their optical and electronic properties by means of different spectroscopic techniques (UV/vis, fluorescence) and electrochemistry, of their thermal properties, and of their ability to self-organize have revealed their promising abilities for use in organic photovoltaics. A series of small molecules based on dithienosilole (DTS) core have also been designed via DFT computations. The calculations show their considerable low bandgap. Their syntheses have been conducted. It anticipates their promising potential for organic photovoltaic applications. Finally, a purely theoretical work has been completed on molecules derived from boron subphthalocyanines. The calculations predict interesting electronic properties for these new materials that may lead to promising performances in organic photovoltaics, paving the way for innovative materials

Numerical simulation on dynamic response of the chest wall loaded by the blast wave

In this paper, a three-dimensional finite element model of the human thorax was constructed using Mimics software and Icem CFD software. This model was loaded with a 100-kPa blast wave and constructed to analyze the dynamic response of the chest wall. The simulation results have shown that a blast wave can cause stress concentration on the ribs and ribs inward movement. The third, fourth, and fifth ribs have the maximum inward moving velocity of 1.6 m / s without any injury for the human body. The three-dimensional finite element model can realistically reflect the characteristic mechanical response of the chest wall to blast wave loadings and can be used for further studies on blast injury mechanism, i.e., injury prediction