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This work presents the hydrothermal synthesis of [Co(2,2′-bipyridine)2(NCS)2] (1) (150 °C, 48 h). The structure of 1 was characterized step by step by elemental analysis CHN, atomic absorption spectroscopy, Fourier transform infrared spectroscopy, thermal gravimetric analysis, differential thermal analysis and single crystal X-ray diffraction. Complex 1 crystallizes in orthorhombic structure with space group Pbca of expected composition. The full geometry optimization and energy values of the highest occupied molecular orbital and the lowest unoccupied molecular orbital were performed using GAUSSIAN 09. Magnetic characterization of complex 1 revealed a paramagnetic behavior at room temperature. Complex 1 was used as a significant precursor to prepare nanoparticles of Co3O4 by thermal decomposition process. The obtained Co3O4 was characterized by various techniques such as FT-IR spectroscopy, powder X-ray diffraction, nitrogen adsorption–desorption isotherms, scanning electron microscope and vibrating sample magnetometer. Co3O4 nanoparticles revealed a ferromagnetic behavior at room temperature. The SEM images of Co3O4 nanoparticles showed an octahedral morphology with a particle size of about 25 nm. Complex 1, commercial, and synthetic Co3O4 nanoparticles were used for the removal of Cr(VI) ions from the aqueous solution. The results showed that Co3O4 nanoparticles which obtained through thermal decomposition of inorganic complex could be employed as an efficient adsorbent for the removal of Cr(VI). Batch adsorption studies were conducted to find the optimal adsorption conditions such as contact time and pH. The results indicate that the adsorption kinetics data followed a pseudo-second-order model. [ABSTRACT FROM AUTHOR]

Background and Objectives: The use of plants for the synthesis of nanoparticles has received attention. The present study aimed to evaluate the antibacterial effects of silver nanoparticles synthesized by Verbena officinalis leaf extract against Yersinia ruckeri, Vibrio cholerae and Listeria monocytogenes. Materials and Methods: Silver nanoparticles were obtained by reacting silver nitrate solution 2 mM and V. officinalis leaf extract. The AgNPs were characterized by UV-visible spectrophotometer, scanning electron microscopy (SEM), and Fourier transform infrared spectrometer (FTIR). To determine minimum inhibitory concentration and test antibiogram of nanoparticle synthesized, broth micro dilution and agar well diffusion methods were used, respectively. Results: The zones of bacterial inhibition were 16 ± 0.5 and 9.16 ± 0.28 mm against Y. ruckeri and L. monocytogenes using 10 and 0.62 mg/mL AgNPs, respectively. Among the studied bacterial species, silver nanoparticles were more effective on Y. ruckeri and L. monocytogenes and less effective on V. cholerae. The highest MIC and MBC of AgNPs (2.5 and 5 mg/mL) were observed for V. cholerae. The lowest MIC and MBC of AgNPs (0.32 and 0.62 mg/mL) were observed for Y. ruckeri, respectively. The MIC and MBC of AgNPs were found to be 1.25 and 2.5 mg/mL for L. monocytogenes. Conclusion: The results clearly indicated that V. officinalis AgNPs have potential antimicrobial activity against Gram-positive and Gram-negative bacteria. [ABSTRACT FROM AUTHOR]

The article presents a study conducted by Hamid R. Memarian and other related to the electronic effect of 4-substitution on the tautomerism in 5-acetyl-2-methoxydihydropyrimidines based on the Nuclear Magnetic Resonance and computational Density Functional Theory. Topics discussed include use of Infrared spectroscopy, Nuclear Magnetic Resonance spectroscopy in characterization of the compound, use of Cyclic voltammetry measurements in determinig electron donating behavior of compound.