Remediation of copper ions from aqueous solution using hybrid magadiite: kinetics,isotherm and mechanism of removal

Research on Chemical Intermediates - This paper deals with the potential use of hybrid magadiite composite as an alternative adsorbent for the removal of copper ions. Na-magadiite was synthesized...     

Hollow fibre-supported graphene oxide nanosheets modified with a deep eutectic solvent to be used for the solid-phase microextraction of silver ions

A deep eutectic solvent (DES) of choline chloride and thiourea was synthesised, immobilised on the surface of graphene oxide (GO) nanosheets and reinforced inside the pores of the hollow fibre (DES-GO-HF). Then, solid-phase microextraction flame atomic absorption spectrometry was designed for separation, preconcentration and determination of trace amounts of silver. Various parameters affecting the extraction recovery of the analyte, such as pH, sample volume, type of DES, extraction time, length of the hollow fiber, nature, as well as the volume and concentration of the eluent, were investigated and optimised. Under optimum conditions, the method showed good linearity in the concentration range of 1.0–40.0 µg L^?1 with the determination coefficient of (r²) 0.9990 for silver. The method was very sensitive and has limits of detection and quantification (defined as 3S_b/m and 10S_b/m) of 0.2 and 0.7 µg L^?1, respectively. The method was successfully applied for the determination of Ag(I) in water, wastewater, ore and hair samples. The accuracy of the method was evaluated through the recovery experiments and the analysis of certified reference materials.     

Corrosion protection of carbon steel in acidic media by expired bupropion drug; experimental and theoretical study

The effects of expired bupropion on the corrosion protection of carbon steel in hydrochloric acid (1.0 M) and sulfuric acid (0.5 M) solutions were examined by Fourier transform infrared (FTIR) spectroscopy, Tafel polarization and electrochemical impedance spectroscopy (EIS). Bupropion concentrations in both acid solutions were raised, which improved corrosion prevention. Bupropion was a mixed inhibitor because it retarded the anodic and cathodic processes, as indicated by polarization data. The inhibition efficiency decreased with the increasing temperature from 25 to 55 °C. In the presence of bupropion, the activation energies of corrosion in both acid solutions increased. The thermodynamic quantities were deduced from the influence of temperature on the corrosion process of carbon steel in both acid media. Bupropion adsorption on carbon steel followed the Langmuir adsorption isotherm. The polarization data yielded outcomes consistent with the results arising from impedance measurements. FTIR spectroscopy showed the active sites of bupropion molecule during adsorption on the alloy surface. The theoretical study and molecular dynamics simulation of bupropion was done by a density functional theory (DFT) approach to realize the effects of molecular structure on the inhibitive action of bupropion.     

Use of phosphorylated chitosan/alumina nanoadditives for polymer performance improvement

Cellulose - In this research, a new generation of ternary nanocomposites based on poly(ethylene terephthalate) (PET), phosphorylated chitosan and surface modified alumina nanoparticles were...     

Enhancement of Congo red dye removal efficiency using Mg-Fe-layered double hydroxide

Research on Chemical Intermediates - In this study, Mg-Fe(II)-Al-layered double hydroxide with different molar ratios Fe/Al (Mg0.80-Fe0.14-Al0.06-LDHs and Mg0.80-Fe0.20-Al0.00-LDHs) was prepared...     

Mechanically changed band gap of single walled carbon nanotube: a third neighbor tight-binding approach

Analytical derivation of electronic band gap of Single Walled Carbon Nanotube (SWCNT) under a small percent of uniaxial and torsional strains is in this paper. Our approach is based on a kind of π-Tight Binding (π-TB) approximation which includes interactions of the second and the third neighbors of each carbon atom in addition to the nearest ones. Implementing the approach of this paper, yields more precise results than those of other researches.     

二氧化硅包覆NiFe_2O_4担载Preyssler杂多酸用于合成双(二氢嘧啶酮)苯和3,4-二氢嘧啶-2(1H)-酮（英文）

A novel magnetic acidic catalyst comprising Preyssler(H14[Na P5W30O110]) heteropoly acid support‐ed on silica coated nickel ferrite nanoparticles (Ni Fe2O4@Si O2) was prepared.The catalyst was characterized by Fourier transform infrared,scanning electron microscopy,transmission electron microscopy,X‐ray diffraction,energy dispersive spectrum,VSM and particle size neasurement.Its catalytic activity was investigated for the synthesis of bis(dihydropyrimidinone)benzene and 3,4‐dihydropyrimidin‐2(1H)‐ones derivatives by the Biginelli reaction.With the catalyst,the reac‐tions occurred in less than 1 h with good to excellent yields.More importantly,the catalyst was easily separated from the reaction mixture by an external magnet and reused at least five times without degradation in the activity.