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Cadmium is one of the most hazardous heavy metal contaminants, and it is usually abundant in the wastewater released from paint and pigment industries. Such effluents urgently need to be treated before their proper reuse for various industrial and agricultural purposes. Therefore, in this study, the process of Cd(ii) ion adsorption from waste aqueous-solutions was investigated using polystyrene (PS), ethanolamine-modified polystyrene (EA-PS), and chromium hydroxide-impregnated ethanolamine-modified polystyrene (Cr@EA-PS) as new effective sorbents. The structural and textual properties as well as the surface charges and particle sizes of the prepared sorbents were examined using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), N 2 adsorption-desorption surface area analysis, X-ray diffraction (XRD), dynamic light scattering (DLS) and zeta potential analysis. Herein, correlations between different features of the three adsorbents and their impacts on adsorption efficiency were extensively investigated. Adsorption kinetics and isotherm studies were also conducted to evaluate the sorption mechanisms and the achieved capacities of the presented adsorbents. Results showed that surface functionalization with ethanol amine particles significantly improved adsorption capacity owing to the introduction of amino groups, providing further interactions with heavy metal species. Moreover, the subsequent impregnation of Cr(OH) 3 into the EA-PS structure could successively enhance surface properties and porosity, leading to observation of the highest adsorption capacity (13.6 mg g -1 for Cr@EA-PS). Such increased adsorption capacity is nearly 10-fold higher than the reported capacity of PS. Kinetic studies revealed that the adsorption process followed a pseudo-second-order model, indicating chemisorption as the primary adsorption mechanism. Isotherm analysis confirmed a favorable monolayer adsorption process exhibited by the three structures. The combination of chemical bonding and physical adsorption mechanisms was observed for Cr@EA-PS, explaining its performance superiority in removing Cd(ii) ions. Thus, the inorganic-organic composite exhibits the highest potential among the three introduced sorbents for practical applications in the field of wastewater treatment., Competing Interests: The authors of this article would like to confirm that there are no conflicts of interests with any organization or any person, and the funding body is listed., (This journal is © The Royal Society of Chemistry.)

Antimicrobial resistance (AMR) is one of ten global public health threats facing humanity. This created the need to identify and develop effective inhibitors as antimicrobial agents. In this respect, quinazolin-2,4-dione hybrids bearing N-heterocyclic cores such as pyrrolidine-2,5-dione, pyrazole and oxadiazole and/or bioactive scaffolds such as hydrazone, amide, sulfonamide, azomethine, and thiourea linkage are described for design, synthesis, antibacterial investigation, and in silico studies. The characterization of the target compounds was accomplished by elemental analysis and various spectroscopic data like FT-IR, 1 H-NMR, 13 C-NMR and MS. The antibacterial evaluation was achieved for the newly synthesized compounds using two G -ve bacteria ( Escherichia coli ATCC 25955 and Pseudomonas aeruginosa ATCC 10145), and two G +ve bacteria ( Bacillus subtilis ATCC 6633 and Staphylococcus aureus NRRL B-767). Synthesized compounds exhibited various activities against the tested pathogens, the results revealed that compound 3c exhibited a characteristic antimicrobial efficacy against all the tested pathogenic strains at a concentration lower than the tested standard drug ranging from 2.5 to 10 μg ml -1 . Moreover, the molecular docking study against the target S. aureus tyrosyl-tRNA synthetase (PDB ID: 1JIJ) was carried out to investigate the mechanism of action of the prepared compounds, which is in line with an in vitro study. Most new compounds exhibited zero violation of Lipinski's rule (Ro5). These candidate molecules have shown promising antibacterial activity. Among these molecules, compound 3c with di-hydroxyl groups on two phenyl rings at position-4 exhibited a promising potent antibacterial inhibitory effect. Further SAR analysis reveals that a greater number of hydroxyl groups in an organic compound might be crucial for antibacterial efficacy. These findings demonstrate the potential activity of compound 3c as an antibacterial agent., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)