parviz aberoomand azar

This work presents a novel self-healing/anti-corrosion coating based on epoxy resin decorated with electrochemically deposited silicon dioxide (SiO2)/linseed oil (LO). For this purpose, the SiO2/LO composite was prepared via a one-pot electrochemical deposition method, which was then utilized as a precursor for epoxy coating preparation. Various techniques, including Fourier Transform InfraRed (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDS), ThermoGravimetric Analysis (TGA), and X-Ray Diffraction (XRD) analysis were used to characterize the coated steel samples. Corrosion current and corrosion potential were decreased following the addition of SiO2 and LO to the steel surface. The mechanism of improved anticorrosion performance of the composite coating can be attributed to the synergistic effect of the components within the composite film. The effect of various coatings on the anticorrosive characteristics of the self-healing coatings has been investigated by electrochemical impedance spectroscopy (EIS), Tafel plots, salt spray, and optical images. The defected self-healing coating consisting of epoxy/SiO2/LO exhibited exceptional healing ability and corrosion inhibition performance toward steel metal as evidenced by EIS and optical images. The SiO2/LO coating layer shows the lowest corrosion current of 0.091 µA/cm2 compared to SiO2 with 0.822 µA/cm2 in corrosive saline media. Furthermore, epoxy-coated SiO2/linseed oil and epoxy-coated SiO2 films on steel supports exhibit corrosion resistances of 1.95×108 and 7.20×107 Ω/cm2 demonstrating better performance of silica-containing linseed oil. It seems that the addition of a hydrophobic linseed oil component can successfully delay the diffusion of water molecules or electrolyte ions, resulting in the improvement of anticorrosion characteristics of the coating layer.

This paper reports the green preparation of silver oxide and nickel oxide nanoparticles. The malva sylvestris extract was used as the green reductant and capping agent. The prepared nanoparticles were characterized using XRD, SEM, FT-IR, and EDX analysis. The XRD analysis discloses that the prepared silver oxide nanoparticles comprise both Ag2O and Ag metal phases. In addition, it was found that the prepared nickel oxide nanoparticles have an amorphous structure. The FT-IR results show the presence of metal-oxide bonds at the wavenumber range 750-600 cm-1. Also, the green synthesis of the metal oxide nanoparticles was confirmed by the existence of the organic functional groups on the surface of the prepared samples. The SEM images show the spherical nanoparticles in the size range below 50 nm for both prepared nanoparticles. These results reveal the superior ability of the malva sylvestris extract to prepare the fine metal oxide nanoparticles. In this research, synthesized Ag2O nanoparticles (Ag2O NPs) and NiO nanoparticles (NiO NPs) were used as modifiers for carbon paste electrode (CPE) and their effect on the electrochemical determination of Quercetin (QCT) was investigated by using differential pulse voltammetry (DPV).

In this research, the synthesis of L/Fe3O4-methionine and graphene oxide and graphene aerogel nanocomposites (Fe3O4/L-Met/GO, Fe3O4/L-Met, Fe3O4/L-Met/GA) was carried out. Then the structure of the synthesized nanocomposites was confirmed by FT-IR, FE-SEM and BET analyses. Then, the effect of different experimental parameters such as initial pH and contact time on the process of cadmium surface adsorption were investigated. The results showed that the highest percentage of cadmium absorption (90%) occurred at Ph=6 by Fe3O4/L-Met/GA nano adsorbent. Therefore, the cadmium (Cd2+) absorption capacity by Fe3O4/L-Met/GA nanocomposite (212.31 mg/g) is higher than the cadmium (Cd2+) absorption capacity by Fe3O4/L-Met nanocomposites (201.23 mg/g). ) Obtained. Adsorption kinetics data showed excellent fit with pseudo-second-order models (R2>0.99) and Freundlich isotherm models.showed high adsorption capacity towards Cd2+ (212.31 mg/g), which was significantly higher than Fe3O4/L-Met (201.23 mg/g). Finally, adsorption kinetics, isotherm studies were investigated. Absorption data showed excellent fit with quasi-second order models (R2> 0.99) and Freundlich isotherm models.

In this study, a new solid phase micro extraction (SPME)fiber coated by sol-gel technology based on polyethyleneglycol (PEG) grafted ionic liquids (ILs), and silicananoparticles (silica NPs) on a porous copper substratewas fabricated. The as-prepared fiber (PEG-ILs-silicaNPs) was then used to extract a variety of pesticides intomato samples before prior to their gas chromatographyflame ionization detection (GC-FID). The key parametersinfluencing extraction efficiency containing includingextraction time, stirring rate, extraction temperature, pH,ionic strength, and desorption temperature, and time wereinvestigated and optimized. The relative standarddeviations (RSDs) for single fiber repeatability rangedfrom 1.2 to 4.6% (n=6), and the RSDs for fiber-to-fiberreproducibility (n=6) were 3.3–6.8%, respectively. Theproposed method based on the PEG-ILs-silica NPs fiberwas successfully applied for the determination of targetedpesticides in tomato samples with good recoveries from89.8 to 103.5% (RSDs=2.1-6.9).

In the present work, the ability of wood-plastic composite containing high density polyethylene and wood powder as a recycled material to remove methylene blue cation pigment was studied. The effect of some important parameters such as pH, adsorbent amount and contact time was investigated. Adsorption efficiencies for methylene blue were maximized at alkaline pH. Adsorption capacity increased with increasing adsorbent amount and contact time. The value of R2 in Langmuir model was equal to 1 and the separation factor for 0.5 and 1 g of adsorbent was 0.09 and 0.1, respectively. Given that the methylene blue adsorption data were more consistent with the Langmuir isotherm model, it can be stated that the wood-plastic composite probably has uniform adsorption surfaces and the adsorption process occurred in a homogeneous system on the adsorbent surface. Based on the results of this study, it was observed that this composite is a suitable adsorbent for removing methylene blue from aqueous solutions and used as a purifying agent in the decolorization of effluents containing pigments. This adsorbent is recyclable and cost-effective for dye removal from textile industry wastewater.

Nd/Pd/TiO2 photocatalyst has been synthesized in the presence of Hydroxyl Propyl Cellulose by sol-gel method with Titanium tetra isopropoxide as titanium precursor. Photocatalyst size and structure properties of the nano-catalyst have been determined by X-Ray Diffraction (XRD). It has contained the anatase phase in advance. The surface area is measured by the Brunauer, Emmett, and Teller (BET) method. The presence of Ti, Nd, and Pd in the nanostructure has been confirmed by EDX, equipped tool with SEM. Photocatalytic degradation of PCB-28 under solar light has been investigated by the Taguchi method with five factors such as the amount of HPC (g/gsol), the percentage of Pd (%), the percentage of Nd (%), calcination temperature (°C), and calcination time (h). Under optimal conditions such as 0.003 of HPC (g/gsol), 0.2 percentage of Pd (%), 0.2 percentage of Nd (%), 700°C of the calcination temperature, and 5 hours for the calcination time, the best desorption result monitored by Solid Phase Nano Extraction (SPNE) technique method before degradation process. By GC-ECD, complete degradation of PCBs was observed after solar irradiation in 14min, and no PCBs chromatogram was observed after this time.

In this research, first, nanoparticles of SrFe11.98Mg0.1Sn0.1O19 hexaferrite was synthesized via sol-gel autocombustion process and then the nanocomposites of hexagonal ferrites/perovskite with the amounts of SrFe11.98Mg0.1Sn0.1O19 /BaTiO3 (50/50, 40/60, 70/30 w/w) was prepared by ball-milling method. FTIR spectra were shown that the bands at about 400 and 500 cm-1 proved the formation of hexagonal ferrites. XRD analysis was confirmed the formation of hexaferrite and perovskite phase of BaTiO3. FESEM pictures was represented the formation of hexagonal nanoparticles and sphere shape of BaTiO3. VSM hysteresis loop was revealed that SrFe11.98Mg0.1Sn0.1O19 belonged to the soft magnetic materials due to the 604.45Oe coercivity. By formation of nanocomposites the coercivity was increased up to 1500 Oe. VNA analysis was VNA analysis revealed that the maximum absorption of -16.4db at 11.5 GHz frequency for SrFe11.98Mg0.1Sn0.1O19 /BaTiO3 (60/40) nanocomposite. Microwave absorption properties of samples was investigated by (vector network analyzer) VNA. The maximum value of reflection loss was --16.4db at 11.5 GHz frequency for SrFe11.98Mg0.1Sn0.1O19 /BaTiO3 (60/40) nanocomposite.

In this research, first, nanoparticles of SrFe11.98Mg0.1Sn0.1O19 hexaferrite was synthesized via sol-gel auto-combustion process and then the nanocomposites of hexagonal ferrites/perovskite with the amounts of SrFe11.98Mg0.1Sn0.1O19/BaTiO3 (50/50, 40/60, 70/30 w/w) was prepared by the ball-milling method. Fourier transform infrared (FTIR) spectrums of SrFe11.98Mg0.1Sn0.1O19,was shown that the bands at about 400 and 500 cm-1 proved the formation of nano hexagonal ferrites. On the FTIR spectrum of nanocomposites, the Ti-O bond of perovskite appeared. X-ray diffraction (XRD) analysis was confirmed the formation of hexaferrite and perovskite phase of BaTiO3. Field emission electron microscopy (FESEM) pictures have represented the formation of hexagonal nanoparticles and sphere shape of BaTiO3. Vibrating sample magnetometer (VSM) hysteresis loop was revealed that SrFe11.98Mg0.1Sn0.1O19 belonged to the soft magnetic materials due to the 604.45Oe coercivity. By formation of nanocomposites, the coercivity was increased up to 1500 Oe. Vector network analyzer (VNA) analysis was revealed the maximum absorption of -16.4 db at 11.5 GHz frequency for SrFe11.98Mg0.1Sn0.1O19/BaTiO3 (60/40) nanocomposite sample.

In this research, a novel method is reported for the surface grafting of n-vinylcaprolactam as a thermosensitive agent and 3-allyloxy-1,2-propandiol with an affinity toward ceftriaxone onto modified magnetic nanoparticles by 3-mercaptopropyltrimethoxysilane. The grafted nanoparticles were characterized by Fourier Transform Infrared Spectroscopy, Elemental Analysis, and Vibrating Sample Magnetometer. The surface morphology was studied using Scanning Electron Microscopy. The resulting grafted nanoparticles were used for determining trace ceftriaxone in biological human fluids. The profile of ceftriaxone uptake by the modified magnetic nanoparticles indicated good accessibility of the active sites in the grafted copolymer. It was found that the adsorption behavior could be fitted by the Langmuir adsorption isotherm model. Solid phase extraction for biological fluids such as urine and serum were also investigated. In this study, a urine extraction recovery of more than 95% was obtained. Overall, magnetic nanoparticles coated with sensitive polymer have proved to enjoy unique properties in biotechnology and drug delivery research.

Sensitized ZnS and Cu-loaded ZnS nanoparticles have been synthesized by chemical precipitation method using anthocyanin as the capping agent and sensitizer. X-ray diffraction, transmission electron microscopy, UV visible spectrophotometer methods were used for the characterization of nanoparticles. Photocatalytic activities of sensitized ZnS and Cu-loaded ZnS were compared in degradation of tetracycline in aqueous solution under visible light irradiation. The progress of the reaction was monitored spectrophotometrically. The different parameters affecting on the photocatalytic reaction such as amount of semiconductor, the initial tetracycline (TC) concentration, the pH of solution, Influence of Cu content and the photocatalytic degradation kinetics of TC were studied. Sensitized Cu-loaded ZnS nanoparticles exhibit high photocatalytic activity during the mineralization of tetracycline under visible light due to decrease of recombination rate of electron–hole pairs. More than 90 % of tetracycline solution degraded with sensitized Cu-loaded ZnS in less than 90 min while Sensitized ZnS was degrading 80 percent within 5 hours.

ZnO- nanoparticles with an average particle size of 24 nm were successfully synthesized using the microwave assisted sol- gel technique. Structural and morphological properties of the nanoparticles were characterized by X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy disperse spectrum (EDS) and Fourier transform infrared spectroscopy (FTIR). The band gap energy was measured to be 3.27 eV. The photocatalytic degradation of tartrazine has been studied in aqueous solution under UV-C irradiation at different pH values, catalyst doses, and tartrazine concentration. Degradation of samples was monitored by a spectrophotometer. Results have shown that 95% of 50 mg L-1 tartrazine was degraded in 120 min due to the photocatalytic degradation in presence of 0.02 g of ZnO-nanoparticles. The photocatalytic degradation kinetics has also been investigated. The experimental data were fitted very well in the pseudo-first-order kinetic and Langmuir-Hinshelwood models.

This paper reports the synthesis and characterization of photocatalyst CdS nanoparticles for investigation of photocatalytic degradation of 2,4,6-trichlorophenol. CdS nanoparticles were synthesized by the microwave-assisted sol-gel method and characterized by various techniques such as X-ray diffraction, filed emission scanning electron microscopy, energy dispersive spectroscopy, Fourier transform infrared spectroscopy and UV-visible spectrophotometer. The average crystallite size was found to be 46 nm. The influences of catalyst amount, contaminant concentration, and pH of the reaction solution were evaluated and optimized. Highest degradation was obtained after 3hours UV-C light irradiation. The kinetic was evaluated in different contaminant concentrations under optimized conditions. It showed that the 2,4,6-trichlorophenol degradation reactions follow pseudo first order kinetic.

Free radicals play an important role in pathological processes such as aging and developing cancer; hence, natural products inhibit free radical production, and can play an important role in preventing diseases. We aimed to evaluate the scavenging activity of free radicals, reducing power, inhibition of lipid peroxidation and malondialdehyde (MDA) formation, and the antioxidant composition of rolB-transformed hairy roots and leaf callus of Catharanthus roseus. Hairy roots of the Catharanthus roseus were induced using Agrobacterium rhizogenes strain ATCC 15834 to transfer the rolB gene. Polymerase chain reaction analysis was used to identify the presence of the gene in the transformed hairy roots. Folin-Ciocalteu reagent, aluminum chloride calorimetry and high performance liquid chromatography were used to determine the content of total phenolic, flavonoid and gallic acid, respectively. To this end, we assayed the free radicals scavenging activity by 1-diphenyl-2-picrylhydrazyl (DPPH), reducing power, inhibition of lipid peroxidation and inhibition of malondialdehyde production. The results showed that phenolic, flavonoid, and gallic acid contents in the ethanol extract of the hairy roots were significantly higher (p ≤ 0.01) than those naturally found in the extracts of root, leaf, and leaf callus of C. roseus. The hairy roots extract showed the lowest IC50 for the inhibition of DPPH•. Furthermore, the ethanol extract showed the best reducing power and had the highest potential to inhibit lipid peroxidation and to form the MDA. The transformed hairy roots can be considered a rich natural source of antioxidants.

Essential oils are isolated from different sections of plants such as flowers, seeds, leaves, stems and roots. Essential oils are applied extensively in producing of perfumes, cosmetics, foods, beverages and confectioneries and as ingredients of disinfectants and insecticides. Experimental: Essential oil are obtained by several isolation methods, such as hydrodistillation (HD), steam distillation (SD), solid phase micro extraction (SPME), microwave assisted distillation (MAD) and solvent free microwave extraction (SFME). Hydrodistillation, solvent free microwave extraction (SFME) and solid phase microextraction (SPME) methods has been applied to extraction of essential oil from Perovskia abrotanoides and Nepeta glomerulosa growing in Iran. Camphor (15.2, 15.50 and 9.02%), 1,8-cineole (15.03, 14.21 and 9.87%) and §-carene (6.4, 7.19 and 9.78%) were the main compounds in the Perovskia abrotanoides essential oil, respectively.  Geraniol(12.74%) and β-caryophyllene (10.05%) identified by hydrodistillation whereas carvacrol (70.52%) and β-caryophyllene (4.13%) identified by solvent free microwave extraction that were the main compounds in the Nepeta glomerulosa essential oil. Industrial and practical recommendations: Hence, it can be High amount of sesquiterpenes and low quantity of hydrocarbon monoterpenes were identified in each essential oil.

When the level of free radicals is increased and also when both the enzymatic systems and low molecular antioxidants are not sufficient to protect the organism, it seems necessary to get antioxidants from external sources. This study aimed to evaluate the antioxidant potential of different parts of Catharantus roseus The antioxidant potential of ethanol extracts of roots, stems, leaves, flowers, seed pods and seeds of C. roseus  plant were measured based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, inhibition of linoleic acid peroxidation by ferric thiocyanate (FTC), and malondialdehyde inhibition by thiobarbituric acid method (TBA) against the standards: Butylated hydroxytoluene (BHT), Butylated hydroxyanisole (BHA) and ascorbic acid.   The phenolic content in the root (61.61 ± 2.58 µg of gallic acid per mg of dried weight extract) according to Folin–Ciocalteu method were more than any other organs. In scavenging a half of DPPH• free radicals (IC50), the extract of root, seed, and leaf (238.9 ± 2.02, 253.78 ± 1.42, 277.95 ± 2.56 µg mL-1),respectively, had the best performance.  In the inhibition of linoleic acid peroxidation, the root extract had the best inhibitory power after ascorbic acid and BHT, and the leaf and seed extract had the performance similar to BHA. The root (78.68 ± 0.54%), and seed (77.44 ± 0.66%) had the best performance in the inhibition of MDA compared with other extracts. Pearson correlation coefficients between the phenolic content and antioxidant capacity of extracts were high and equal to -0.838, 0.895, and 0.740, respectively, according to DPPH, FTC and TBA methods. The results of this study can be promising in the potential of other applications of the plant organ especially in the inhibition of free radicals and lipids' peroxidation.