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A novel magnetic graphene nanocomposites (MGN) was fabricated via a environment-friendly electrochemical exfoliation in Fe2(SO4)3 aqueous solutions. Ferrous sulfate in the electrolyte had the potential to enhance both the exfoliation efficiency of graphite and the in-situ magnetization of graphene. The as-obtained MGN-700 °C was explored as an adsorbent for the removal of Congo red (CR) from aqueous solutions. The adsorption equilibrium was rapidly achieved in 20 min, and the kinetic adsorption was well fitted with the pseudo-second-order kinetic model. Meanwhile, the adsorption isotherms followed the Freundlich model with a maximum capability of 582 mg g−1 for CR. Moreover, thermodynamic study indicated that the adsorption process was spontaneous and exothermic. Characterizations of the adsorbent suggested that the adsorption mechanisms of CR onto MGN-700 °C mainly involved hydrogen bond, electrostatic interaction and π–π stacking. After five cycles of adsorption/desorption, the removal efficiency of CR onto MGN-700 °Cremained at approximately 80%, demonstrating its excellent reusability. Furthermore, the adsorbent exhibited high adsorption capacity and a ferromagnetic feature, indicating its potential practical application in dye wastewater treatment. [ABSTRACT FROM AUTHOR]

A series of Si4+ or Gd3+ doped KBa0.9BP2O8:0.1Eu3+ phosphors emitting orangish-red light were successfully synthesized via a conventional high-temperature solid-state method in air atmosphere. The crystal structure and luminescence properties of the phosphors were characterized. The effects of calcination temperature and different ions (Si4+ or Gd3+) co-doping amount on the crystal structure and spectra properties of the phosphors were investigated. The excitation spectra includes a series of spikes in 310–500 nm with the maximum excitation peak of wavelength at 394 nm that matches with the near ultraviolet (UV) LED chips. Under the near UV excitation at 394 nm, the maximum and the sub-strong emission peak appears orange light at 594 nm and red light at 614 nm, which belongs to 5D0 → 7F1 and 5D0 → 7F2 transition of Eu3+, respectively. The results indicate Si4+ or Gd3+ have no obvious influence on the emission peak positions of phosphors, but leads to the change of R/O value. Furthermore, doping Si4+ or Gd3+ both can enhance the luminous intensity of phosphors. [ABSTRACT FROM AUTHOR]

A quantitative method for the analysis of trace anions of dyestuffs by microwave ablation ion chromatography was established. The effect of pH on the separation efficiency, the effect of different drenching solutions on the retention time, the effect of flow rate on the peak height, peak area, separation, and theoretical talk plate number were investigated through the analysis of ion chromatographic interferences. The results showed that the best separation was achieved on SH-AC-3 anion column with pH 10.12 and flow rate of 1.0-1.2 mL/min. The separation time was only 12 min with sodium hydroxide as the eluent. The spiked recoveries were 97.6%-101%, the anion precision was < 0.03%-2.6%, and the instrument quantitative and qualitative precision was < 3.0%. This method has the advantages of precision, accuracy stability which is of practical application for the determination of the content of halogen introduced in the 2,6-position of the Aza-BODIPY fluorescent dye. [ABSTRACT FROM AUTHOR]

Super-thermal insulation materials have important applications in the field of building insulation. The construction of one-dimensional nanotube thermal insulation materials is expected to further reduce their thermal conductivity. Organosilica nanotubes are fabricated using an in situ interfacial sol–gel reaction at the inverse-emulsion interface. Compared with the preparation method of silica aerogel, this one-pot sol–gel method is facile and can be carried out at room temperature. The nanotube morphologies and gelation process can be controlled. Because of their hierarchical porous structures, the as-formed nanotube materials have high thermal insulation properties, which are below that of air. [ABSTRACT FROM AUTHOR]