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The powder of treated watermelon seeds (WST), obtained through hexane extraction, has proven to be a promising adsorbent for the environmentally friendly and cost-effective removal of Basic Yellow 28 (BY28) using adsorption techniques. By optimizing conditions through Central Composite Design (CCD), focusing on key factors such as temperature, adsorbent weight, and dye concentration, we aimed to enhance the efficiency of the adsorption process. Our study assessed the accuracy of the model and regression coefficients through analysis of variance (ANOVA). The results revealed a strong agreement between the predicted values derived from the model and the experimental values for BY28, with a coefficient of determination (R2) equal to 0.92, indicating a high level of reliability and effectiveness of the developed model in predicting the adsorption behavior of BY28 on WST. Under optimal conditions, including a temperature of 35°C, an adsorbent weight of 2.45 g/L, and a dye concentration of 50 mg/L, the adsorption process demonstrated exceptional efficiency. This study highlights the remarkable potential of treated watermelon seeds for the removal of organic pollutants, emphasizing the importance of using sustainable and readily available agricultural materials for environmental remediation, thus contributing to both environmental conservation and cost-effectiveness in wastewater treatment processes.

This study focuses on the potential of treated avocado seed to remove azoic organic dyes (basic yellow 28 and tartrazine). The treated avocado seed was characterized, and batch adsorption studies were carried out to evaluate the effects of several removal dye parameters (contact time, ionic strength, initial concentration, adsorbent dose, and temperature). The adsorption kinetics of the dyes examined showed that the adsorption mechanism on the two selected catalysts followed pseudo-second-order kinetics (R2 > 0.999). The adsorption process of each dye was reported to fit using five non-linear regressions. Freundlich and Temkin adsorption isotherms described well the adsorption of basic yellow 28, and Freundlich adsorption isotherms described well the adsorption of tartrazine on the Treated Avocado Seed. The results suggested that the maximum amount adsorbed was 49.30 mg/g for basic yellow 28 and 38.43 mg/g for tartrazine and a high removal rate of 89.93% for BY 28 and 93.22% for tartrazine and that a chemical, spontaneous and endothermic process of adsorption occurred. Boyd’s expression demonstrated a mechanism of film diffusion for adsorption. Based on the findings, we suggest the application of activated avocado seeds for the removal of azoic dyes in aqueous solutions.

In this paper, we focused on the green synthesis of titanium dioxide (TiO2) nanoparticles via an ecofriendly process using Citrus limon extract. Several analytical techniques were used to characterize the prepared samples: X-ray diffraction (XRD), infrared spectroscopy, Raman spectroscopy, Scanning Electron Microscopy (SEM) and X-ray photoelectrons spectroscopy (XPS). XRD diffractograms revealed an anatase crystal structure of TiO2. SEM analysis showed the presence of particles with nanometric sizes, and the Fourier transform infrared (FTIR) spectra confirmed the presence of the synthesized nanoparticles. The antibacterial activity of the green prepared TiO2 nanoparticles was assessed. Additionally, the antibacterial efficiency of the green prepared TiO2 nanoparticles was compared with TiO2 nanoparticles prepared via a chemical process. The results prove the efficacy of this ecofriendly process. This method can be used for the rapid and environmentally friendly biosynthesis of stable titanium oxide nanoparticles. This work is a contribution to the valorization of bio-sources for the synthesis of titanium dioxide crystals using Citrus limon fruit extract and tetrabutile titanate as a precursor.

La tempête Alex, qui a touché le 2 octobre 2020 les vallées de la Roya, la Tinée, et la Vésubie dans les Alpes-Maritimes, constitue un événement de référence qu’il est important de documenter au mieux pour en conserver la mémoire et permettre son étude ultérieure. Les différents services et opérateurs de l’État se sont largement mobilisés pour acquérir et regrouper des jeux de données décrivant cet événement. Cet article présente une contribution de la communauté scientifique à la reconstitution des débits de pointe des crues, conduite dans le cadre du programme de recherche HyMeX. Des relevés de sections d’écoulement ont permis d’obtenir 32 estimations de débits de pointe, contribuant à la connaissance des crues observées sur les cours d’eau principaux et leurs petits affluents.

Biosynthetic procedure is the best alternative to the preparation of nonmaterials as the challenges faced by the scientist from the last few decades. Present research reports cost-effective, inexpensive eco-friendly synthesis of titanium dioxide nanoparticles using a methanolic extract of fruits peel agro-waste. X-ray diffraction spectrum of identified TiO2NPs found noncrystalline in nature. Fourier transform infrared showed O–H, C = O, C–O, and C–H functional groups present in the fruit peel involved in the biosynthesis of TiO2NPs. The prominent peak at 1708, 1720 and 1700 cm−1 observed in the spectrum attributed to O–Ti–O stretching in Plum, Kiwi and Peach mediated TiO2NPs. The SEM images of all three TiO2NPs revealed cylindrical in shape. The size of TiO2NPs synthesized from Plum, Kiwi and Peach were found to be 47.1 and 63.2, 54.1 and 85.1 and 200 nm, respectively. All the TiO2NPs exhibited size- and dose-dependent antibacterial and antioxidant activities.

An eco-friendly and efficient method was developed for the preparation of a new series of sulfur-containing quinolinthiones. Compounds 6a–o were synthesized from 4-methyl-2-thiocoumarin and arylhydrazides using water as a solvent under microwave irradiation. Some noteworthy features of our novel method are its cleanliness, short reaction time and high conversion rate, and the reaction proceeds (profiles) using a simple procedure. All of the prepared compounds were screened for their antibacterial efficacy in vitro using the disc diffusion method against bacterial strains. Compound (6j) showed the greatest potency with a 16 and 19 mm inhibition zone against Klebsiella pneumonia and Staphylococcus aureus, respectively.

An efficient and ecofriendly method for the synthesis of disubstituted 5-aminopyrimidines from vinyl azides and urea or thiourea was developed. This reaction proceeds under microwave irradiation conditions in the presence of water as a solvent. The remarkable features of this new protocol are high conversion, short reaction times, cleaner reaction profiles and straightforward procedure.

Animal-bone-meal-supported palladium (0) was prepared and used as catalyst in the Suzuki coupling reaction in water, under sunlight as an alternative source of energy. This palladium has showed a high catalytic activity than tetrakis(triphenylphosphine) palladium (Pd(PPh3)4) in the Suzuki cross-coupling reaction (the reaction of 4-halogenopyridopyrimidine with boronic acids) in water via sunlight as the light source, with no addition of ligands. This green method affords heteroaryls with excellent yields in comparison with the classical method using tetrakis(triphenylphosphine) palladium. The green catalyst did not show any significant loss of activity, even when used up to five times.