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This study presents the development of three new chiral stationary phases (CSP). Three new peptides CSPs with a main chain of L-proline (L-Pro), L-phenylalanine (L-Phe), L-valine (L-Val) and L-leucine (L-Leu) and different terminals of L-citrulline (L-Cit), L-lysine (L-Lys) and L-tryptophan (L-Typ) immobilized on 3-aminopropyltrimethoxysilane modified silica gel (APS) were prepared, furthermore, successful analyses and characterizations were conducted using Fourier transform infrared spectra, elemental analysis, and thermogravimetric analysis. After this, the enantioselective performance of the three L-Pro-L-Phe-L-Val-L-Leu peptide stationary phases columns were evaluated. The evaluation used 9 racemic compounds under normal-phase high performance liquid chromatography mode. Optimized enantiomeric separation conditions were established. Under these conditions, the resolutions of flurbiprofen, naproxen, benzoin, 1,1'-bi-2-naphthol and ketoprofen on the CSP-1 column were 1.61, 2.0, 0.62, 0.52, and 1.20, respectively. In addition, the reproducibility of the CSP-1 column was also investigated. The results of the investigation illustrated that the stationary phases have good reproducibility (RSD = 0.12%, n = 5).

Peanut shell, a widely available agricultural waste, was successfully grafted with quaternary ammine groups on its surface by using amination modification. The sorption mechanism of U(VI) on the amine cross-linked peanut shell (PNN) was examined by batch experiments and spectroscopy analysis. The physical adsorption was dominated by the liquid film diffusion and the intra-particle diffusion, whereas the chemical adsorption was dominated by surface complexation with quaternary amine groups and carboxyl groups. The maximum adsorption capacity of U(VI) on PNN was calculated to be 574.81 mg g−1 at pH = 6.0 and T = 298 K, which was much higher than that of U(VI) on pristine pure peanut shell and many other materials. Consideration of the high sorption efficiency and eco-friendliness of peanut shell, PNN presented promising potential in the preconcentration of radionuclides in radioactive pollution management.

The nanoscale zero valent iron (NZVI) modified coal fly ash (CFA) magnetic composites (NZVI/CFA) were synthesized from the waste CFA and applied for the high-efficiency sequestration of U(VI) ions from water solution. The sequestration capacity of U(VI) ions on NZVI/CFA (0.62 mmol·g−1) was larger than that on bare CFA (0.25 mmol·g−1) or NZVI (0.38 mmol·g−1). The sequestration of U(VI) on NZVI and NZVI/CFA was primary controlled by outer-sphere surface complexation at low pH, and by inner-sphere surface complexation at high pH. According to the thermodynamic data and the adsorption isotherms' analysis, the U(VI) sorption process to the NZVI/CFA was spontaneous and endothermic. The main reaction mechanism was that, most of the soluble U(VI) ions were firstly adsorbed to NZVI/CFA and then the surface adsorbed U(VI) was partly reduced to U(VI) on the porous NZVI/CFA composites, and this synergistically affected U(VI) removal from solution to NZVI/CFA. The results of DFT calculation indicated that the NZVI/CFA had a strong sequestration capacity towards U(VI) and U(IV) ions, and the binding energy of U(IV) species was larger than that of U(VI) species, which evidenced the higher sorption of U(IV) than U(VI) on NZVI/CFA. The results showed that NZVI/CFA was an appropriate material for U(VI) sequestration from large volumes of actual effluent in wastewater cleanup.

Concerns about the potential environmental risks of zinc oxide nanoparticles (ZnO NPs) are becoming an important issue because of their rapid growth in different fields. ZnO NPs are inevitably released in the environment during the production, transport, use and disposal process. Therefore, it is necessary to understand their toxicities and mode of actions. This review summarizes the toxic effects of ZnO NPs with different properties and exposed conditions on different species. The mechanisms of ZnO NPs on living organisms could be mainly attributed to one or more of the following aspects: the physical damage of direct contact, the dissolved zinc ions and the ROS-mediated mechanism. This paper systematically reviews the toxic effects of ZnO NPs on organisms and puts forward the existing problems, which are helpful for the safe and efficient use of ZnO NPs, providing the basis for further study of the toxic effects of ZnO NPs and establishing a comprehensive and safe evaluation system.

Germanium is considered as a potential anode material for sodium-ion batteries due to its fascinating theoretical specific capacity. However, its poor cyclability resulted from the sluggish kinetics and large volume change during repeated charge/discharge poses major threats for its further development. One solution is using its ternary compound as an alternative to improve the cycling stability. Here, high-purity CuGeO3 nanowires were prepared via a facile hydrothermal method, and their sodium storage performances were firstly explored. The as-obtained CuGeO3 delivered an initial charge capacity of 306.7 mAh g−1 along with favorable cycling performance, displaying great promise as a potential anode material for sodium ion batteries.

In this study, ternary Cu2SnS3 (CTS) nanostructure materials with high crystallinity were successfully prepared via a facile solvothermal method, which was followed by high-temperature treatment. The morphology of the as-synthesized samples is uniform flower-like spheres, with these spheres consisting of hierarchical nanosheets and possessing network features. Sodium storage measurements demonstrate that the annealed CTS electrodes have high initial reversible capacity (447.7 mAh&middot, g&minus, 1 at a current density of 100 mA&middot, 1), good capacity retention (200.6 mAh&middot, 1 after 50 cycles at a current density of 100 mA&middot, 1) and considerable rate capability because of their high crystallinity and unique morphology. Such good performances indicate that the high crystallinity CTS is a promising anode material for sodium ion batteries.