The atmospheric reaction of a series of furan compounds (furan (F), 2methylfuran (2-MF), 3-methylfuran (3-MF), 2,5-dimethylfuran (2,5-DMF), and 2,3,5trimethylfuran (2,3,5-TMF)) with nitrate radical (NO 3 ) has been investigated using the relative rate kinetic method in the CHamber for the Atmospheric Reactivity and the Metrology of the Environment (CHARME) simulation chamber at the laboratoire de Physico-Chimie de l'Atmosphere (LPCA) laboratory (Dunkerque, France). The experiments were performed at (294 ± 2) K atmospheric pressure and under dry conditions (relative humidity, RH < 2%) with proton transfer mass reaction−time of flight−mass spectrometer (PTR-ToF-MS) for the chemical analysis. The following rate coefficients (in units cm 3 molecule −1 s −1 ) were determined: furan, 5.82 ± 1.21) × 10 −11 , and 2,3,5-trimethylfuran, k (2,3,5-TMF) = (1.66 ± 0.69) × 10 −10 . The uncertainty on the measured rate coefficient (Δk FC ) includes both the uncertainty on the measurement and that on the rate coefficient of the reference molecule. To our knowledge, this work represents the first determination for the rate coefficient of the 2,3,5-TMF reaction with NO 3 . This work shows that the reaction between furan and methylated furan compounds with nitrate radical (NO 3 ) is the dominant removal pathway during the night with lifetimes between 0.5 and 55 min for the studied molecules.

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The inhibition effect of quince pulp extract (QPE) on the adsorption and corrosion of carbon steel in 1M HCl solution was investigated using the weight loss method, potentiodynamic polarization and impedance spectroscopy measurements. At first, the quince extract was characterized, its polyphenolic content was qualitatively and quantitatively determined and its anti-oxidant activity was assessed. The HPLC-DAD-MS showed that the quince extract contained a high quantity of polyphenols with the main compounds being neochlorogenic acid, rutin and chlorogenic acid (7.68, 9.05 and 18.57 mg/g fw, respectively), which represent together about 84 % of total phenolics. The extract exhibited a strong antioxidant potential as it inhibited 87 % of the DPPH Á anionic radical. The polarization measurements indicate that the extract acts as a mixed inhibitor. The values of inhibition efficiency increase with inhibitor concentration reaching a maximum value (88 %) at 5 9 10 -1 g/L. The presence of QPE enhances the values of R t and reduces the C dl values. The adsorption of QPE under consideration on a steel/acidic solution

The corrosion inhibition and adsorption of ethanol extracts of leaves (LV), stems (ST) and roots (RT) of Rotula aquatica plant for mild steel in H 2 SO 4 solutions were investigated using conventional weight loss, gasometric techniques, electrochemical polarizations and electrochemical impedance spectroscopy. The results showed that all the three extracts of Rotula aquatica plant performed well as inhibitor for the corrosion of steel in sulphuric acid media and the inhibition efficiencies of the extract follow the trend RT > LV > ST. Inhibition efficiencies increased with increasing concentration of the plant extracts but decreased with the temperature rise for all cases. Both the cathodic hydrogen evolution and the anodic dissolution of mild steel were inhibited, hence the active molecules of all the extracts studied acted as mixed type corrosion inhibitors.