Photocatalytic degradation of an organic dye, emerald green, on nano titanium dioxide (anatase 99.5%) at basic buffer pH of 7, 8 and 9 has been investigated. The effects of various operating parameters such as initial concentration of dye, catalyst dosage, bufferic pH and irradiation time on photocatalytic degradation have been studied in a photoreactor cell containing high pressure mercury lamp to obtain the optimum conditions. COD removal was found to be 65-71% confirming considerable mineralization. The photodegradation of the dye obeyed a pseudo-first order kinetics according to the Langmuir-Hinshelwood model at all used buffer pH. The observed rate constants (k obs) of photocatalytic degradation were 3.3 × 10-2 min-1 , 7.09 × 10-2 min-1 and 1.32 × 10-1 min-1 at buffer pH of 7-9 respectively. Furthermore, the Langmuir-Hinshelwood rate constants, k r and adsorption constants, K A are reported for current process at various buffer pH.

A new tetradentate Schiff base ligand entitled as (L = (N2E, N2′E)‐N1, N1′‐(ethane‐1,2‐diyl)bis(N2‐((E)‐3‐(2‐nitrophenyl)allylidene)ethane‐1,2‐diamine) and its six cadmium(II) complexes formulated as CdLX2 in which X is Cl, Br, I, NO3, NCS, or N3 were synthesized under ultrasound irradiation and characterized by various physical and spectral techniques. Moreover, some complexes were also prepared in nanostructured dimensions confirmed by scanning electron microscopy (SEM), energy dispersive X‐ray analysis (EDXA), and X‐ray powder diffraction (XRPD) techniques and then were used as precursor for preparation of CdO nanoparticles via direct calcination at 600°C. As typical, the crystal structure of cadmium(II) nitrate complex was determined using single crystal X‐ray diffraction. Accordingly, it was found that [Cd(L)(NO3)2] complex crystallizes in the monoclinic space group P21/n with two independent molecules in the asymmetric unit with two coordination modes of nitrate anions. This complex has zero‐dimensional (0D) coordination supramolecular structure. Hirshfeld surface analyses suggested that H … O (49.5%), H … H (30.3%), and H … C (11.8%) intermolecular interactions are most considerable in the crystal packing. Computational studies of ligand structure leading to electrostatic potentials of the solid state geometry and some occupied molecular orbitals (HOMO, HOMO‐1, HOMO‐2, and HOMO‐5) prevailing the contribution of nitrogen lone pairs are also reported. Thermal behavior studies of the compounds under nitrogen atmosphere from room temperature to 900°C revealed that the ligand is completely decomposed without any residual whereas the complexes are decomposed via two to four thermal steps with trace amount of metallic cadmium as residue. Moreover, antibacterial and antifungal screening well showed that the complexes inhibit from the growth of the various bacteria and fungi more efficient than free ligand especially against Gram‐positive bacteria. DNA cleavage potentials of the compounds may be one of the reasons for their antimicrobial activity.

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A new tetradentate Schiff base ligand (L) (L = obtained by condensation reaction between triethylenetetraamine and (E)‐3‐(2‐nitrophenyl)acrylaldehyde) and some of its zinc (II) complexes formulated as ZnLX2 in which X = halide/pseudohalide were synthesized and characterized by some physical and spectral techniques such as infra‐red (IR), nuclear magnetic resonance (NMR), UV–Visible, microanalyses, and conductivity measurements. Among the complexes, zinc chloride, iodide, and nitrate complexes were also prepared as nanostructure powder under sonication conditions confirmed by x‐ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x‐ray analysis (EDAX). Moreover, zinc oxide nanoparticles were prepared by direct thermolysis of nanopowder of ZnLI2 complex under air atmosphere. Moreover, the thermal behaviors of the compounds were studied based on thermo‐gravimetric (TG)/differential thermal gravimetric (DTG)/differential thermal analyses (DTA) analyses data under nitrogen atmosphere. Furthermore, antibacterial/antifungal activities of the ligand and its zinc complexes were screened by the well diffusion method against some bacteria and funguses. Ultimately, the DNA cleavage potential of the compounds was evaluated by gel electrophoresis technique.

In this paper, five new zinc‐Schiff base compounds formulated as ZnLX2 (L is a new N3‐Schiff base ligand obtained by condensation reaction between diethylenetriamine and (Z)‐3‐(4‐(dimethylamino)phenyl) acrylaldehyde and X is (Cl−, Br−, I−, N3−, and NCS−)) were synthesized and characterized by Fourier transform infrared, 1H and 13C NMR, UV–visible, thermal analyses, and molar conductivity measurements. Low molar conductivity values of the compounds in dimethylformamide (DMF) showed nonelectrolyte character of them. Zinc complexes have been also prepared in nanostructure sizes under ultrasonic irradiation confirmed by X‐ray powder diffraction and scanning electron microscopy. Thereafter, ZnO nanoparticles were prepared by direct calcination process of zinc iodide complex at 600°C under air atmosphere. Furthermore, thermogravimetric analyses of the complexes were used for the investigation of thermal behavior of the tiled compounds. Based on TG/DTG plots, some kinetics activation parameters of the compounds at all thermal decomposition steps were calculated. In final, antimicrobial activities of the compounds were investigated by the well diffusion technique against the gram‐positive bacteria of Staphylococcus aureus and Bacillus subtilis, and the gram‐negative bacteria of Escherichia coli and Pseudomonas aeruginosa and the fungi strains of Aspergillus oryzae and Candida albicans. The results showed that all zinc‐Schiff base organic compounds are more antimicrobial active than free ligand.

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