نشریه شیمی کاربردی روز
پیاپی 66 (بهار 1402)

In this paper, a solid phase extraction based on magnetic graphene oxide nanocomposite has been introduced for the quantitative extraction of bupropion. The characterization and structural studies for the nanocomposite were carried out by fourier transform infrared spectrometry, scanning electron microscopy and X–ray diffraction techniques. Ion mobility spectrometry as a sensitive, rapid and simple method was applied for the determination of bupropion. The effect of experimental parameters (including desorption solvent: type and volume, adsorbent amount, pH, temperature and time extraction, and initial solution volume) on the extraction efficiency of the proposed method was investigated. Under optimum conditions, the calibration curves were linear in the two ranges of 4–10 and 10–24 ng with coefficients of determination R2≥ 0.98. The relative standard deviation was 5% and also the limits of detection and quantification were 0.66 and 2.20 ng, respectively. The proposed method was applied for the different brand tablets with various doses of bupropion which the satisfactory quantitative results were obtained (recovery: 88.0–92.0%).

Today, biodiesel is being produced and consumed around the world as one of the main sources for replacing fossil fuels. In current research, cobalt doped zinc oxide was used as nanocatalyst to produce biodiesel from soybean oil by transesterification reaction. The nanocatalysts used were first prepared by microwave method and identified by X-ray diffraction (XRD), scanning electron microscopy (SEM) and x-ray energy dispersive spectroscopy (EDS). In the next step, the prepared catalysts were used in the reaction of biodiesel production from soybean oil. The produced biodiesel was characterized using nuclear magnetic resonance spectroscopy (NMR) and gas chromatography-mass spectroscopy (GC-MS). Optimal reaction conditions of biodiesel production with cobalt doped zinc oxide nanocatalyst obtained, at 3 h, temperature 60 ˚C, catalyst concentration 3% by weight, and molar ratio of oil to methanol 1 to 41 resulted in 98% efficiency. In another part of this research, microwave radiation with a power of 250 W was used as a source of energy in the biodiesel production reaction which in the presence of 4% by weight of catalyst and molar ratio of oil to methanol 1 to 20 resulted in 91% efficiency in 180 s.

Recently, considerable attention has been focused on heteropoly acids including their anions (polyoxometalates or POMs) due to many advantages such as simple preparation, high reactivity, non-corrosive, non-pollutant and excellent stability. POMs have been used as photocatalysts for the destruction of dyes. Discharge of wastewater of synthetic dyes to environment affects both living organisms of aquatic ecosystems and human health due to toxicity and carcinogenicity. Consequently, treatment of dye-contaminated wastewaters with decontamination processes is necessary before their discharge. In this study, magnetic activated carbon nanoparticles (MAC) were coated with an organic hybrid of phosphotungstic acid that makes MAC suitable for adsorption and photocatalytic degradation of dyes. The prepared composite was characterized by Fourier transform infrared spectroscopy, powder X-ray diffraction, thermal analyses, scanning electron microscopy and vibrating sample magnetometer. Dye adsorption and photocatalytic properties of composite was examined by studying the decolorization of model dyes methylene blue (MB), methyl orange (MO) and their mixture solutions. The results show that the composite can selectively adsorb MB molecules from binary mixtures of MB/MO. While the visible light is not able to degrade alone MO solution in the presence of composite, it degrades the MO mixed with MB solution. The composite is, unlike MAC, a good photocatalyst in the degradation of dyes under sunlight and visible irradiation and can be separated by magnet, recovered and reused. Removal is via combination of adsorption and then photocatalytic degradation through direct oxidation by composite.

In this research, nanoparticles of the (1) [PdCl2(aemptrz)], and (2) [Pd2(μ-mmtz)4].2CH3CN, have been synthesized using ultrasonic waves in the ultrasonic bath (sonochemistry method, which is one of the methods of liquid state processing) at constant temperature and different times. Both complexes were analyzed using (XRD) and (FTIR) techniques. Nanoparticles of PdO, prepared by calcination in an electric furnace and characterized by (FESEM), (XRD), and (FT-IR) techniques. The results of XRD analysis showed that the synthesized PdO nanoparticles (resulting from nano complexes 1 and 2) crystallized in the space group P42/mmc of the tetragonal (for 1) and P2/c space group of the monoclinic (for 2) systems. The results of the FESEM micrographs showed that the size of the synthesized PdO particles derived from nano complex (1) and (2) is between 35.44 - 61.36 and 34.21 - 67.69 nm, respectively.

In this paper, the degradation of p-nitrophenol (PNP) by high gravity technology in the presence of Fenton reagent is investigated. In this process, a rotating packed bed reactor with a blade packing consisting of twelve blades was used. The purpose of this study was to investigate the effect of pH (3, 4, and 5), as well as the rotational speed of the rotating packed bed (600, 800, 1000, and 1200 rpm), the flow rate of inlet liquid (50 and 100 l/h), the dosage of hydrogen peroxide (1.25, 2.25, 3.25 and 4.25 ml) and the concentration of ferrous sulfate (0.1, 0.3, 0.4, 0.5 and 0.6 mM) on the PNP degradation. The initial solution contains 100 mg / l PNP. The results showed that excessive increase of rotational speed (more than 800 rpm) and increase of liquid inlet flow rate to 100 l/h did not contribute to the degradation of pollutant and reducing PNP removal efficiency. Increasing the amount of hydrogen peroxide from 1.25 to 3.25 ml improves the degradation of the pollutant, but increasing this amount to 4.25 does not help to improve the PNP removal process. Increasing the concentration of ferrous sulfate from 0.1 to 0.5 mM reduces the degradation time of the contaminant, but increasing the concentration to 0.6 mM has the opposite effect. In the best case, ie pH 5, the rotational speed of 800 rpm, the liquid inlet flow rate of 50 l/h, Fe2 + concentration of 0.5 mM, and H2O2 of 3.25 ml, PNP in 70 minutes destroyed completely (100%).

In this work, two Schiff bases named 1-(2-hydroxybenzylidene)-4-phenylthiosemicarbazide (2-HTSC) and 1-(3-hydroxybenzylidene)-4-phenylthiosemicarbazide (3-HTSC) were synthesized and evaluated their inhibitory properties on corrosion of carbon steel in 15% HCl environment. Inhibitory effect of compounds were investigated by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), polarization, Scanning electron microscopy (SEM) analysis, X-ray diffraction (EDX) spectroscopy and absorption isotherms. Concentrations of 0.5, 1, 1.5 and 2 mM of the inhibitor were evaluated and the best result was obtained at a concentration of 1.5 mM. The results showed that the 3-HTSC Schiff base has a better inhibitory percentage than the Schiff base 2-HTSC. Adsorption of inhibitors on the steel surface follows all Langmuir adsorption isotherm and the results of thermodynamic parameters indicate physico-chemical adsorption. In the presence of inhibitor, the adsorption rate of chloride ions on the metal substrate decreased by 26% and 74% for inhibitors 2-HTSC and 3-HTSC, respectively, due to the predominance of better interactions of 3-HTSC with the metal substrate in Comparison with 2-HTSC inhibitor.

Here in this research a novel bis-salophen schiff base ligand anchored magnetic Fe3O4@SiO2 nanoparticles was prepared and applied for removal of Pb(II) from aqueous solutions. The obtained adsorbent Fe3O4@SiO2/Schiff base MNPs was characterized by using broad range of characterization techniques including fourier transform infrared (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray analysis (EDX) and vibration sample magnetometry (VSM). After synthesizing bis-salophen schiff base ligand immobilized on Fe3O4@SiO2 nanoparticles, the adsorption activity of this adsorbent for lead ions by nonmagnetic, in terms of effect of adsorbent dosage on the adsorption and kinetics behavior was investigated in detail. Furthermore, the adsorption and regeneration experiment showed there was about 91% in the adsorption capacity of the prepared Fe3O4@SiO2/Schiff base MNPs for lead. Finally, our results suggested that the Fe3O4@SiO2/Schiff base composites have a great potential to be employed for treatment of water and wastewater containing lead(II).

Stable ylide of di-tert-butyl-2-(2-indolinon-1-yl)-3-(trimethoxyphosphorane ylidene) butanedioate was synthesized by means of catalyst-free reaction of trimethyl phosphite, di-tert-butylacetylene dicarboxylate and 2-indolinone in n-hexane/diethyl ether at ambient temperature. Obtained product was characterized by 1H, 13C, 31P NMR, FT-IR and mass spectroscopy. The crystal structure of the stable ylide was determined by X-ray crystallography. The title compound crystallized in monoclinic, space group P21/c and cell parameters a=15.8079(7) Å, b= 18.7521(13) Å, c =17.4987(10) Å, β= 95.504(6)° and Z=8. The X-ray study showed that adjacent carbonyl group (C291=O291, C191=O191) in the ylide moiety of compound had a resonance with bond of C=P. These results show clearly that environment of C(19, 29) is planar.

In this work, the micellization behavior of tetradecyltrimethylammonium bromide ‎‎(TTAB) surfactant was investigated in aqueous solvent mixtures of methanol, ethanol ‎and propanol on different mass fractions (10-30%) and aqueous solution of Ponceau 4R ‎and Sunset yellow FCF dyes at concentrations (0.001-0.007mM) based on ‎conductometric technique at T=(298-313)K. The critical micelle concentration (CMC) ‎values and dissociation degrees of TTAB surfactant were determined. The obtained ‎results showed that the CMC value increases with rising of methanol and ethanol mas ‎fractions but the CMC value decreases with rising of propanol mas fractions. Also, the ‎obtained results indicated that the CMC value decreases with concentration increasing of ‎Ponceau 4R and Sunset yellow FCF dyes. In addition, thermodynamic properties such as ‎the Gibbs energy, enthalpy and entropy of micellization were calculated as a function of ‎temperature, dye concentration and alcohol mass fractions. ‎

In this research, first, the cobalt (III) complex of 20,15,10,5-tetrakis (tetra(4-carboxyphenol)) porphyrin (Co-THPBP) was synthesized and its terminal acidic groups were chlorinated using thionyl chloride. Then, in order to stabilize the desired complex on the chitosan polymer substrate, the chlorinated cobalt-porphyrin complex was modified using protected 4-aminophenol, and as well as by deprotection of the terminal hydroxyl group of 4-aminophenol, the modified complex was attached to the chitosan polymer substrate. The prepared compounds were characterized using Fourier transform infrared spectroscopy (FT-IR), 1H NMR, Ultraviolet–visible spectroscopy (UV-Vis), scanning electron microscope (SEM), Diffuse Reflectance Spectroscopy (DRS). The prepared compound was applied for the photocatalytic removal of methylene blue in the presence of visible light. The results confirmed that the presence of chitosan polymer substrate has a significant effect on increasing the photodegradation of methylene blue dye.

Non-invasive detection of explosive materials concealed in the container is became one of the defense priorities, due to the increasing of organized crimes and terrorist activities. In this research, detection of ammonium nitrate(AN) concealed in common polymer containers such as polypropylene(PP) and high density polyethylene (HDPE) using different Deep Raman techniques such as spatial offset Raman spectroscopy (SORS), time-resolved Raman spectroscopy (TRRS) and the integration of these two techniques is known as time resolved spatially offset Raman spectroscopy(TR-SORS) has been performed. Since the ability to detection of explosives at a safe distance is a critical issue in the defense, a stand-off Deep Raman set-up at a distance of 5m was set up to detect AN concealed in HDPE container. The SORS ratio has been considered as a criterion, to evaluate the accuracy of the performance and to express a measure of the correctness of the qualitative identification, in all recorded spectra. This value in the TR-SORS technique for detection of AN in the PP container in the near distance, HDPE container in the near and far distance was 3.3, 11.5, and 3.5, respectively. The results of research showed that the integration of spatial offset Raman spectroscopy and time-resolved Raman spectroscopy will improve the SORS ratio, which is important in the safe identification of suspicious packages without harming the package and the user.

In the present work, a computational analysis of the chemical structure of curcumin, the most important component of turmeric, is carried out by means of state-of-the-art methods of calculations. High-level ab initio calculations (G4) along with reliable methods of density functional theory (DFT) have been used to studythe enol-diketo tautomerism of curcumin. The electrochemical behavior of curcumin has been also investigated by means of cyclic voltammetry and standard theoretical quantum chemical calculations in a mixed solvent of water-ethanol. The pH dependence of the redox activity of curcumin derivatives in the mixture solutions at different temperatures has been used for the experimental determination of the standard reduction potential and changes of entropy, enthalpy, and Gibbs free energy for the studied reaction. The electrooxidation process leads to several products that are studied theoretically using DFT calculations. The calculated values of E° are in good agreement with the experiment. Uniquely, the change of solvation energy for the studied reaction has been investigated by two models and the results are in perfect agreement with one another.

In this manuscript,, the synthesis and characterization by NMR spectroscopy of the two novel platinum complexes with the imine ferocene with different coordination mode to platinum center, Pt(Cl)2(dmso)(Imine) (1) and Pt(Me)(dmso)(Imine) (2) was introduced , in which the ligand was attached as the monodentate ligand in (1) and in (2) the ligand was attached as the cyclomatalated bidentate ligand , were introduced for checking their anticancer properties. Also their interaction waith DNA was studied by UV-Vis titration technique. In addition, Molecular docking simulation by Schrödinger sofware was used for checking the various possible attachment mode of their interaction with DNA.

In this study, graphene oxide (GO) was synthesized through the improved Hummer method and sulfonated graphene oxide nanoparticles (s-GO) were prepared by effective sulfonation reaction. To evaluate the effectiveness of nanofiltration membranes, the membranes were prepared based on the mixing of polyether sulfone with graphene oxide (GO) and sulfonated graphene oxide nanoparticles. Synthesis of GO and s-GO nanoparticles was structurally evaluated using FT-IR and Raman spectroscopy. Nanocomposite membrane containing nanoparticles were fabricated via phase inversion method and their performance was evaluated using membrane evaluation tests. Surface, cross-section morphology and membrane structure were observed by FE-SEM. The wettability of the membrane surface was determined by the test of contact angle, membrane porosity, water absorption and average membrane pore radius. Nanofiltration membrane performance was evaluated by measuring pure water flux, dye removal ability, desalination from aqueous solution, removal of heavy metals, fouling rate and flux recovery ratio. It seems, practically very hydrophilic -OSO3H groups located on GO surfaces can increase the hydrophilicity of the membrane and improve its anti-fouling properties in the final membrane. Fouling test for graphene sulfone-containing membranes showed better results.