Physicochemical Studies of 4-Substituted N-(2-Mercaptophenyl)-Salicylideneimines: Corrosion Inhibition of Mild Steel in an Acid Medium

A series of 4-substituted N-(2-mercaptophenyl)salicylideneimine Schiff bases were synthesized and investigated for corrosion inhibition of mild steel in hydrochloric acid medium. Inhibition through adsorption mechanism is proposed for these inhibitors, which is well supported by electrochemical impedance spectroscopy, the Langmuir adsorption isotherm and Scanning Electron Microscope morphologies of inhibited and uninhibited mild steel specimens. The negative ?G _ads indicates the spontaneous adsorption of the inhibitor on a mild steel surface. Among all the examined inhibitors, 5-bromo-N-(2-mercaptophenyl)salicylideneimine showed a higher inhibition efficiency. In order to reveal the usefulness of these Schiff bases as corrosion inhibitors under various circumstances, weight loss measurements were performed at various temperatures, acid concentrations and immersion times.     

Interface Oxygen Vacancy-Enhanced Co3O4/WO3 Nanorod Heterojunction for Sub-ppm Level Detection of NOx

Herein, a cobalt oxide/tungsten oxide (Co₃O₄/WO₃) p–n heterojunction for NO_x detection is developed and optimized. Field-emission scanning electron microscopy shows that the WO₃ nanorods are embellished with Co₃O₄ nanostructure. X-ray photoelectron spectroscopy reveals the presence of oxygen vacancy on the Co₃O₄ coupled with WO₃ heterojunction. Compared to bare WO₃ and pure Co₃O₄, the Co₃O₄/WO₃ heterojunction sensor shows significant sensitivity to NO_x at 200 °C. The sensor exhibits higher linearity from 0.4 to 10 ppm of NO_x, with a sensing response of 4.4–93%. The NO_x sensitivity of the Co₃O₄/WO₃ heterojunction sensor is ninefold higher than that of the pure WO₃ sensor. Even in a high humidity (84%) environment, the Co₃O₄/WO₃ heterojunction sensor demonstrates high NO_x sensitivity. The sensor maintains remarkable stability measured for up to 4 weeks. The possible NO_x sensing mechanism of the Co₃O₄/WO₃ heterojunction is additionally discussed.     

Performance Enhancement and Comparison of Graphene Field Effect Transistor Devices Coated with HMDS Layer

Silicon - Graphene-based devices show good transfer characteristics, which depend upon the surface morphology of the material and substrate. During fabrication of the device, the substrate...     

Study on the effect of atmospheric and low-pressure plasma and its combination on the microbial reduction and quality of milk

This study is aimed to identify the effects of atmospheric and low-pressure plasma on milk individually and in combination, as the plasma generated and applied at different conditions have variations in the effect on food. Plasma bubbling unit (200 V and 0.24 A) was used for atmospheric plasma and Dielectric Barrier Discharge discharge plasma (70 Pa) with milk passing between the electrodes was used for low-pressure plasma. After treatment, the initial coliform load of 7.62 log CFU/ml was decreased by a maximum of 1.26, 1.58, and 2.2 log reduction, when milk was treated using low-pressure plasma (2 kV and 3 ml/min milk flow rate), plasma bubbling (10 min) and combination of both atmospheric bubbling and low-pressure plasma application (10 min bubbling +2 kV and 3 ml/min milk flow rate) respectively. The conductivity (significantly increased) and pH (slight reduction) of milk supported the presence of reactive species. However, alkaline phosphatase activity was not eliminated in plasma-treated milk; the initial activity in terms of mg phenols/ml of milk was 23.20 which was reduced to 22.57 in low-pressure plasma and 22.35 in plasma bubbling, however, it increased while both the treatments were combined. The sodium dodecyl sulfate–polyacrylamide gel electrophoresis analysis uncovered that the plasma processing didn't have any prominent impact on the protein fractions in milk. Though plasma bubbling was effective compared to low-pressure plasma, the combination was proved to have a synergistic effect on milk. However, the enzyme structure needs to be studied in the future for analyzing the exact change in the activity.