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Background and Objective: Due to the water shortages and the presence of industrial pollutants in water resources, wastewater treatment, especially colored wastewater, is essential. The aim of this study was to treat wastewater containing Methylene Blue dye using activated carbon nanocomposite/zinc oxide nanoparticles (ZnO/AC) obtained from canola oil waste by green method. Materials and Methods: In the present study, the effect of different parameters (pH, Methylene Blue concentration, adsorbent amount, temperature and contact time) on the adsorption of Methylene Blue was investigated. Design of Experiment 7 software (Response Surface Method (RSM)) was used to evaluate the influence of various parameters on Methylene Blue removal. Results: The results of the predicted experiments showed that the highest adsorption of Methylene Blue is at pH = 10, temperature 70 °C, contact time of 50 min, initial adsorption concentration of 10 mg/ L and adsorbent amount of 0.05 g. Under optimal conditions, ZnO/AC adsorbent was able to remove 98.22% of Methylene Blue from the aqueous medium. Conclusion: Appropriate to the high potential of ZnO/AC nanocomposite in the removal of Methylene Blue pigment, it can be a good candidate for the removal of dye contaminants and wastewater treatment of textile factories.

In this study, the effects of solvent on the electrode potentials of menthol and carvacrol species were investigated experimentally and computationally and their antioxidant properties were compared in different solvents by calculating the half-wave potential E1/2 of species, Vand Dissociative Energy (BDE), Ionization Energy (IE), and Electron Affinity (EA). Electrochemical behavior of menthol and carvacrol species in four solvents (MeOH, EtOH, DMSO, and Heptane) were studied using cyclovoltametric technique in a glass electrode as a working electrode and the calculations for obtaining the electrode potential were performed using DFT functional including B3LYP with 6-311+G(d,p)basis set and PCM and IEFPCM models for calculation of solvent energy. Finally, the results were compared and confirmed by experimental methods. Where in the compound carvacrol represent more properties antioxidant than menthol due to lower values E1/2 in gas and solution phases. Also, the lower BDE in the gas phase is 80.19 kcal/mol compared with menthol (98.91 kcal/mol). Moreover, compound carvacrol has the IE value of 1.12 eV smaller than menthol and has the EA value of 0.35 eV higher than menthol. Calculations show that the model had no effect on computational results. Also, according to the results, the antioxidant properties of carvacrol in non-polar solvents were higher due to the smaller amount of E1/2.

In this work, magnetic activated carbon (MGAC) was investigated to remove the antibiotic cefazolin from aqueous solutions as well as its antibacterial properties. To determine the optimal process conditions and achieve maximum efficiency, the effect of temperature, contact time, initial concentration of the drug, composite dosage, and pH using the response surface method (RSM) and the central composite design model (CCD) were investigated by DOE software. Structural characteristics and morphology of the nanocomposite were analyzed by using FTIR, XRD, EDAX, SEM, TEM, BET, TGA, VSM, analyzes. The results showed that pH = 6, the temperature of 30 ℃, contact time 150 minutes, initial concentration of drug 20 mg/l, and composite dosage 0.03 g were the best conditions for removing cefazolin from aqueous solution. In these conditions, the magnetically activated carbon was able to remove 96% of cefazolin. The Langmuir, Freundlich, and Temkin isotherms were also studied and the results showed that the absorption behavior is most consistent with the Temkin isotherm. The results of thermodynamic experiments also showed that the adsorption process is exothermic and spontaneous. Finally, the antibacterial properties of the prepared nano composite on Streptococcus and Salmonella were investigated and the results showed that the prepared sample has antibacterial properties.

Corrosion inhibitory impacts of turmeric with concentrations of 200-800 ppm on the electrochemical behavior of mild steel were studied in the medium of NaCl 3.5% using several techniques such as electrochemical impedance spectroscopy (EIS) and polarization. Scanning electron microscopy (SEM) was used for analyzing the surface of mild steel after 24 hours of immersion in the electrolyte solution, with and without turmeric. The results of polarization and EIS demonstrated that for the steel sample immersed in a salt solution containing 800 ppm of turmeric extract, the corrosion current density was decreased and the corrosion potential was shifted to positive values. On the other hand, the electric capacitance of the double-layer was decreased and the charge transfer resistance and inhibition efficiency were increased, confirming an improved corrosion resistance compared to the other sample concentrations. SEM results for the mentioned inhibitor with 800 ppm concentration showed a more even and continuous film formed on the surface of mild steel and no corrosion products was observed.

MOF-5 has been employed as a powerful catalyst for the preparation of 2-amino-4H-chromene. A wide variety of aromatic aldehydes was condensed with malononitrile and 2-naphthol under mild and solvent-free conditions in the presence of the trace amount of catalyst. A variety of 2-amino-4H-chromene can be obtained in good to excellent yield up to 95% in relatively short time reaction and easy workup. MOF-5 has been employed as a powerful catalyst for the preparation of 2-amino-4H-chromene. A wide variety of aromatic aldehydes was condensed with malononitrile and 2-naphthol under mild and solvent-free conditions in the presence of the trace amount of catalyst. A variety of 2-amino-4H-chromene can be obtained in good to excellent yield up to 95% in relatively short time reaction and easy workup.MOF-5 has been employed as a powerful catalyst for the preparation of 2-amino-4H-chromene. A wide variety of aromatic aldehydes was condensed with malononitrile and 2-naphthol under mild and solvent-free conditions in the presence of the trace amount of catalyst. A variety of 2-amino-4H-chromene can be obtained in good to excellent yield up to 95% in relatively short time reaction and easy workup. MOF-5 has been employed as a powerful catalyst for the preparation of 2-amino-4H-chromene. A wide variety of aromatic aldehydes was condensed with malononitrile and 2-naphthol under mild and solvent-free conditions in the presence of the trace amount of catalyst. A variety of 2-amino-4H-chromene can be obtained in good to excellent yield up to 95% in relatively short time reaction and easy workup.MOF-5 has been employed as a powerful catalyst for the preparation of 2-amino-4H-chromene. A wide variety of aromatic aldehydes was condensed with malononitrile and 2-naphthol under mild and solvent-free conditions in the presence of the trace amount of catalyst. A variety of 2-amino-4H-chromene can be obtained in good to excellent yield up to 95% in relatively short time reaction and easy workup.

Schiff bases, an aldehyde- or ketone-like compounds in which the carbonyl group is replaced by an imine or azomethine, are some of the most widely used organic compounds. In this study, the quantum mechanics calculations were performed on M(Chel) where M=Ni(II) and Chel= BAE (bis-acetylacetoneethylenediimine), BBE=bis(benzoyl acetone)ethylenediimine, BFE= bis(1,1,1-triflouroacetylacetone) ethylenediimine and BCE = bis(3-chloroacetylacetone) ethylenediimine) ligands using Gaussian 03 and hartree-fock theory (HF) at B3LYP/6-311G level in the gas phase and solution phase. The polarized continuum model (PCM) is used to calculate salvation energies. After optimizing, various parameters such as electrode potentials, energy gap, chemical hardness, chemical potential and electrophilicity in solvent (DMSO) have been calculated. It was found to be planar and four coordinate. Reduction potentials toward a given M(II) according to the Schiff base ligands changed in the trend: BAE >BCE >BFE.

In this study, the adsorption of thallium (I) ion as a dangerous pollutant from aqueous solution onto modified ZnO nanopowder as a fairly cheap adsorbent has been examined in batch mode. It was known that modification of the adsorbent was necessary to reach a significant adsorption percentage. The adsorbent used here was modified by sodium phosphate solution. The effect of experimental conditions such as initial pH of solution, contact time, adsorbent dosage, initial concentration of thallium and temperature is studied. The results showed the dependence of the adsorption percentage to these conditions specially its pH. The maximum adsorption percentage of Tl (I) ions at 25±1oC was 92.8%. Freundlich isotherm model provided a better fit with the experimental data than Langmuir and Temkin isotherm models by high correlation. Separation factor, RL, values showed that modified ZnO nanopowder was favorable for the adsorption of Tl (I) ion. The negative value of ΔH0 showed that Tl (I) sorption is an exothermic process and the negative value of ΔS0 represented that there is a little decrease of randomness at the solid-solution interface during sorption.

A novel ion-selective poly(vinyl chloride) membrane sensor for Fe(III) ions based on Tris-(1,2-diiminocyclohexylmethyl-5-Cl-2-hydroxyl benzaldehyde) are reported in this paper. The electrode exhibits a good potentiometric response for Fe(III), response time ≤ 20 s, over a wide concentration range 1.0 × 10-5 to 1.0 × 10-1 M with a slope 19.4 ± 0.5 mV/decade. The potentiometric response is independent on the pH of solution in the range of 1.5-5.0. The proposed electrode can be used for at least two months without any considerable divergence in potentials.It exhibits very good selectivity relative to a wide variety of alkali, alkaline earth, transition and heavy metal ions. The electrode assembly was also used as indicator electrode in the potentiometric titration of Fe(III) with EDTA.

The formation constants of species formed in the system H+ + alanine and VO2+ +alanine have been determined in aqueous solution for 1.0

The stability constants of the systems dioxovanadium(V) with alanylalanine, alanylglycine, and alanine have been determined in aqueous solution in 0.8 ≤ pH ≤ 5 at 25°C and 0.1 mol-dm−3 (NaClO4), using a combination of potentiometric and spectrophotometric techniques. The compositions of the formed complexes were determined and it was shown that dioxovanadium(V) forms two mononuclear 1:1 and 1:2 species with alanine of the type VO2L and VO2L2−, and two mononuclear 1:1 complexes with alanylpeptides of the type VO2HL and VO2L−.