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Use of ultrasound as an additional source for promoting polymerization reactions has gained great attention. Phase transfer catalyst (PTC) along with ultrasonication in polymerization process is an attractive methodology to achieve good yield and realizing principles of green chemistry. Herein, we reported the facile polymerization of synthesized novel N-butenyl isatin (NBI) at 60 ± 2 °C with and without ultrasonic irradiation (45 kHz; 550 W) using dual-site phase transfer catalyst (1, 4-bis (triethyl methyl ammonium) benzene dibromide, TEMABDB) and potassium peroxydisulphate (PDS or PPS) as initiator. Ultrasonication (US) promotes the formation of reactive radicals, which can be utilized effectively in phase transfer polymerization process. Hence, the rate was multi-folded (twice) in comparison with silent condition. The effect of sonication frequency and various reaction parameters on the polymerization process were investigated in both conditions. An enhancement of reaction rate under sonication was validated by activation parameter. Synthesized monomer and poly (N-butenyl isatin) was characterized by different spectral methods. Facile polymerization of N-butenyl isatin by sonication aided dual-site PTC. Green approach and mild conditions used for polymerization of NBI. Sonication lifts the rate significantly in comparison with standard condition. Effects of variables in polymerization rate were explored in both conditions. Poly (N-butenyl isatin) was analyzed by different spectral techniques. [ABSTRACT FROM AUTHOR]

The ongoing exponential increase in population intensifies the overexploitation of food, water, energy, and other resources. Overcoming the problem has emerged as a tedious task, and the most probable solution seems to be upgradation in agricultural practices. To achieve a superior quality harvest with maximum yield, synthetic herbicides, insecticides, weedicides, and pesticides have been extensively developed and employed. These pesticides generally wash down to the water bodies, polluting the water and causing serious health issues for human, animal, and aquatic lives. The suggested study uses a zinc peroxide (ZnO2) based carbon composite doped with sulphur adsorbent to remove the very hazardous pesticide thiamethoxam (TMX) from the contaminated water in a cost‐effective and efficient manner. In an acidic environment, a remarkable removal efficiency of 99.5 % is achieved at pH levels 1–3. Additionally, at pH level 11, an impressive removal rate of 96.4 % is obtained. Furthermore, this composite material exhibits a high adsorption capacity of 142.86 mg/g. The batch studies experiments revealed that the adsorption of TMX. complied with the Langmuir isotherm model and demonstrated Pseudo‐second order kinetics. The adsorbent eco‐friendly and effective, can be prepared easily, is ecologically friendly, and does not cause any sort of secondary pollution. The present work has high potential to take the science of water purification to the next step further. [ABSTRACT FROM AUTHOR]

Chromic acid (Cr6+) anodization process is widely used for the corrosion protection of aircraft aluminium alloys. Hexavalent chromium being toxic in nature need to be phased out by eco-friendly alternatives. In the present study modified tartaric-sulphuric acid (TSA) process has been developed followed by sealing in permanganate based bath to obtain 4 to 6 µm thick anodic oxide layer on 2024-T3, 6061-T6 and 7075-T6 aluminium alloys. The process was carried out using a pilot scale anodizing plant. The anodized specimens were characterized for visual observation, thickness, adhesion, electrical breakdown voltage, corrosion resistance and tensile behaviour. All the tests were carried out as per MIL-A-8625F specifications. The specimens were also subjected for about 800 hrs to real time corrosion testing, 200 metres away from sea shore at Mandapam Camp, Rameshwaram, India. The performance of the permanganate sealed TSA anodized aluminium alloys are comparable with that of the conventional chromic acid anodized coatings. This chromic acid-free anodization process has been qualified to airworthiness regulating standards by Indian military certification authorities. Efforts are in progress to commercialize this technology for use on aero platforms. [ABSTRACT FROM AUTHOR]

Crystal violet (CV) dye is one of the most toxic dyes majorly generated by textile industries. It may cause health issues if enters human beings. A lot of research has been reported for the removal of CV dye from wastewater; however, most of them are time-consuming and hardly remove more than 95% of the CV dye. In the last few years, we have tested several materials, and most of them have exhibited very low efficacy toward adsorption of CV including zinc peroxide (ZnO 2 ). To enhance adsorption efficacy, dispersibility, and stability, the surfaces of several reported materials were modified using different wetting agents and nonionic surfactants. Interestingly, ZnO 2 , which was earlier very less effective after surface modification by sodium salt of dioctyl sulfosuccinate, efficiently adsorbed >99.5% of CV from contaminated water within 5 min of contact time at pH ∼10. The adsorption capacity obtained for the sodium docusate surface-modified zinc peroxide (ZnSD) adsorbent was found to be 123 mg/g, which is much better than the other reported for CV removal. Different physiochemical experiment parameters like pH, contact time, initial dye concentration, adsorbent dosages, and temperature were optimum to achieve maximum adsorption of the CV dye. The adsorption rate and adsorption mechanism studies show that the adsorption of CV follows pseudo-second-order kinematics and the Freundlich isotherm model. The adsorption results are consistent, and even treated water can be reutilized for various applications., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)