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A novel electrochemical sensor was constructed based on modification of polyaniline (PANI) and graphitic-phase carbon nitride (g-C 3 N 4) composites. Detection of Cd(II) ions in the aqueous environment using differential pulsed anodic stripping voltammetry (DPASV) technique. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), contact angle (CA), and Tafel curve analyses were used to characterize the physical and electrochemical properties of electrode. We prepared a new PANI@g-C 3 N 4 composite material by combining the two substances based on their respective advantages. The composite material was applied to electrode detection for the first time, which significantly enhanced the transfer of free electrons on the surface of the electrode, improved the sensitivity of the electrode, increased the adsorption capacity of Cd ions, and significantly improved the detection effect of the electrode. Parameters such as the amount of PANI@g-C 3 N 4 modification, deposition potential, deposition time and solution pH were optimized to determine the best conditions for the detection of Cd(II) ions. Under optimal conditions, our sensor achieves a best signal at −0.78 V (vs. Ag/Agcl electrode), and exhibits a wide linear concentration range of 0.1–140 μg/L with a low detection limit of 0.05 μg/L. The sensor was successful in implementing the identification of real water samples with recoveries ranging from 91 % to 106 %. The relative standard deviation (RSD) is less than 4.31 %. Besides, the sensor has outstanding anti-interference, repeatability and steadiness. The successful application of this sensor provides a new idea for efficient detection of Cd(II) ions in aquatic environments. [Display omitted] • PANI and g-C 3 N 4 composites were firstly used to modify GCE for Cd(II) detection. • The composite improves the electrode conductivity and Cd adsorption performance. • The PANI@g-C 3 N 4 @GCE shows a low Cd detection limit with wide linear range. • This sensor was also applied to the detection of Cd(II) ions in real water samples [ABSTRACT FROM AUTHOR]

This work adopted a simple and green method for synthesizing a composite of magnetic carboxylic multi–walled carbon nanotube–metal–organic frame (MCNTs–UiO–66–NH 2) at room temperature, which was applied to the remediation of ibuprofen (Ibu) and naproxen (Nap) in wastewater. The influencing factors of adsorption were investigated, including adsorbent dosage, pH value, coexisting ions, temperature, and contact time, etc. Various methods were employed for analyzing the structural features and surface characteristics exhibited by MCNTs–UiO–66–NH 2. The values of max adsorption quantity about MCNTs–UiO–66–NH 2 toward Ibu and Nap reached 143 mg·g–1 and 139 mg·g–1 at 313 K, respectively. The Langmuir model and Pseudo–second–order model can describe the adsorption process of Ibu and Nap. According to the values of the thermodynamic parameters, both adsorption processes were endothermic, spontaneous and could lead to an increase in entropy. In addition, the composite can be used to capture Ibu and Nap in the pH range of 1–10 and the salinity range of 0–0.2 mol·L–1 with an ideal regeneration performance taking 5 mmol·L–1 NaHCO 3 as eluent. The mechanism of adsorption is including complexation, π–π conjugation, electrostatic action and H–bonding. These properties confirm MCNTs–UiO–66–NH 2 as one potential adsorbent for remediation of Ibu and Nap in wastewater. [Display omitted] • The preparation process of MCNTs-UiO-66-NH 2 is simple, green, economical and operable at room temperature. • MCNTs-UiO-66-NH 2 has high adsorption performance for Ibu and Nap. • There are good salt tolerance, acid and alkali resistance and regeneration property about the adsorption process. • MCNTs-UiO-66-NH 2 can be quickly separated from wastewater. [ABSTRACT FROM AUTHOR]

• Better preparation of alloy coatings by scanning electron beam technology. • The coating prepared by scanning electron beam showed a composite gradient. • The elements in the melt pool are sufficiently stirred to create segregation. • Martensite structure in the superheated zone can also be delaminated. The surface WC/Ni-Co based alloying treatment of 30CrMnSi steel was carried out using scanning electron beam technology, and the tissue distribution after alloying were tested and investigated. The results show that the cross-section of the alloyed specimen consists of three parts: the alloy layer, the heat affected zone and the substrate. The thickness of the alloy layer was increased by 18.3 μm compared to the thickness of the pre-coated layer. The alloy layer is organised in a composite gradient, consisting of martensite and ledeburite with carbides. [ABSTRACT FROM AUTHOR]

A kind of novel composite nanophosphor consisting of corroded SiO 2 and La 2 MoO 6 :0.14Eu3+ (abbreviated as LMO:0.14Eu3+) had been successfully synthesized by hydrothermal approach followed by calcination. The mic-morphology of the composite material was observed by FE-SEM. The positive effect of corroded SiO 2 on the luminescence performance of phosphor had been studied in detail. The SiO 2 corroded by different concentrations of NaOH changed the diffuse reflection path of excitation light and the stacked structure of nanophosphor. Under the excitation of 465 nm, the excitation light was more continuously scattered in SiO 2 -LMO:0.14Eu3+ nanophosphor than in LMO:0.14Eu3+ nanophosphor, which caused more activator ions Eu3+ were successfully activated to enhance the luminescence intensity and color purity. The results suggest that adding corroded SiO 2 to improve optical conversion properties of phosphors might become a relatively effective method. • The SiO 2 -La 2 MoO 6 :0.14Eu3+ material had been successfully synthesized by hydrothermal approach followed by calcination. • The corroded SiO 2 changed the diffuse reflection path of excitation light and the stacked structure of nanophosphor. • The value of the luminescence intensity of nanophosphor increased by 57.3%. • The color purity of nanophosphor increased by 3.959%. • The mechanism of adding corroded SiO 2 to improve the luminescence performance of phosphor is explained. [ABSTRACT FROM AUTHOR]