Characterization of relative n-isoclinism of a pair of lie algebras

No Abstrac

Application of a dispersive micro-solid-phase extraction method for pre-concentration and ultra-trace determination of cadmium ions in water and biological samples

A method for the trace determination of cadmium ions in water, human urine and human blood serum samples using ultrasonic-assisted dispersive micro-solid-phase extraction (UA-D-μSPE) was developed. Silica-coated magnetic nanoparticles were coated with polythiophene, and the resulting sorbent was characterized using thermogravimetry, differential thermal analysis, scanning electron microscopy, Fourier transform infrared spectrometry and X-ray diffraction. Following UA-D-μSPE, cadmium ions were quantified using graphite furnace atomic absorption spectrometry. A Box�Behnken design was used for optimization of important sorption and desorption parameters in UA-D-μSPE: in the sorption step, pH of solution, sorption amount and sonication time for sorption; in the desorption step, concentration of eluent, volume of eluent and sonication time. The optimum conditions for the method were: pH of solution, 7.5; sonication time for sorption, 3 min; sorption amount, 35 mg; type and concentration of eluent, HCl and 1.1 mol l�1; volume of eluent, 360 μl; sonication time for desorption, 110 s. Under the optimized conditions the limit of detection and relative standard deviation for the detection of cadmium ions by UA-D-μSPE were found to be 0.8 ng l�1 and <6, respectively. Copyright © 2017 John Wiley & Sons, Ltd

Green synthesis of silver nanoparticles using aqueous extract of Stachys lavandulifolia flower, and their cytotoxicity, antioxidant, antibacterial and cutaneous wound-healing properties

In a biological process where the herbal tea (Stachys lavandulifolia) aqueous extract was applied as a capping and reducing agent, nanoparticles (NPs) of silver (Ag) were synthesized. These AgNPs were characterized using Fourier transform-infrared spectroscopy, field emission-scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy and ultraviolet-visible spectroscopy. The synthesized AgNPs had great cell viability dose-dependently investigating the effect of the plant on human umbilical vein endothelial cell line and indicated this method was non-toxic. In this study, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging test was carried out to examine antioxidant properties, which revealed similar antioxidant properties for AgNPs and butylated hydroxytoluene. Agar diffusion tests were applied to determine the antibacterial characteristics. The macro-broth tube test was run to determine minimum inhibitory concentration. All data of antibacterial and cutaneous wound-healing examinations were analyzed by SPSS 21 software (Duncan post hoc test). AgNPs showed higher antibacterial property than all standard antibiotics (p <= 0.01). Also, AgNPs prevented the growth of all bacteria at 2-8 mg/ml concentrations and destroyed them at 2-16 mg/ml concentrations (p <= 0.01). For the in vivo experiment, after creating the cutaneous wound, the rats were randomly divided into six groups: untreated control; treatment with Eucerin basal ointment; treatment with 3% tetracycline ointment; treatment with 0.2% AgNO3 ointment; treatment with 0.2% S. lavandulifolia ointment; and treatment with 0.2% AgNPs ointment. These groups were treated for 10 days. For histopathological and biochemical analysis of the healing trend, a 3 x 3-cm section was prepared from all dermal thicknesses at day 10. Use of AgNPs ointment in the treatment groups substantially reduced (p <= 0.01) the wound area, total cells, neutrophil, macrophage and lymphocyte, and remarkably raised (p <= 0.01) the wound contracture, hydroxyl proline, hexosamine, hexuronic acid, fibrocyte and fibrocytes/fibroblast rate compared with other groups. Seemingly, AgNPs can be used as a medical supplement owing to their non-cytotoxic, antioxidant, antibacterial and cutaneous wound-healing properties

The conjunction of a new ultrasonic-assisted dispersive solid-phase extraction method with HPLC-DAD for the trace determination of diazinon in biological and water media

Herein, a new ultrasonic-assisted dispersive solid-phase extraction method using a TiO2/magnetic graphene-based sorbent in conjunction with the HPLC-diode array detection (HPLC-DAD) was successfully developed for the trace detection of diazinon. Initially, the TiO2/magnetic graphene-based sorbent was successfully synthesized and subsequently characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDS) and elemental mapping techniques. Then, the sorbent was used for the sorption and extraction of diazinon mainly through �-� stacking hydrophobic interactions. Under the optimized conditions, the calibration curves were linear over the concentration range of 0.8-800 μg L-1 for urine, plasma and milk samples and 0.2-200 μg L-1 for water samples. The method detection limits were determined to be in the range of 0.05-0.3 μg L-1 based on a signal-to-noise ratio of 3 (S/N = 3). To test the extraction efficiency, the method was applied to various fortified real samples. The average recoveries obtained from the fortified samples varied between 92-104 with relative standard deviations of 6.1-10.2. Finally, the method was determined to be effective for the analysis of diazinon in environmental and biological samples. © 2018 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique

Effect of sunlight and ultraviolet radiation on the efficacy of Fe-doped titanium dioxide (Fe-TiO2) nanoparticles for the removal of furfural from aqueous solutions

Furfural, chemical compound very harmful to human health and difficult to degrade, is used or generated in many industries, including petrochemical, paper, and oil refining industries. The study evaluates the performance of Fe-TiCh nanoparticles for the removal of furfural in the presence of sunlight and UV radiation. Fe-TiO2 nanoparticles were prepared by the sol-gel method, and the characteristics of the resultant nanoparticles were determined using scanning electron microscopy. Samples with known concentrations of furfural and nanoparticles were individually exposed to sunlight and UV radiation under varying conditions, and the residual furfural concentration was measured using high- performance liquid chromatography. The results showed that for both processes the efficiency of furfural removal increased with increased reaction time, nanoparticle loading, and pH, whereas the efficiency decreased with increased furfural concentratioa The highest removal efficiencies of the Fe-TiCh/UV and Fe-TiCh/sun processes were 95 and 76%, respectively. In general, the degradation and elimination rate of furfural using Fe-TiO2/UV process was higher than Fe-TiCVsun process because TiO2 nanoparticles can only be activated upon irradiation with photons of light in the UV domain