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Ischemic stroke is one of the leading causes of morbidity and mortality in humans. Cerebral ischemia-reperfusion (CIR) injury serves as a leading cause of stroke.

We demonstrated the controlled growth of two-dimensional (2D) hexagonal tin disulfide (SnS2) nanoflakes with stacked monolayer atomic steps. The morphology was similar to flat-topped and step-sided mesa plateaus or step pyramids. The SnS2 nanoflakes were grown on mica substrates via an atmospheric-pressure chemical vapor deposition process using tin monosulfide and sulfur powder as precursors. Atomic force microscopy (AFM), electron microscopy, and Raman characterizations were performed to investigate the structural features, and a sequential layer-wise epitaxial growth mechanism was revealed. In addition, systematic Raman characterizations were performed on individual SnS2 nanoflakes with a wide range of thicknesses (1–100 nm), indicating that the A1g peak intensity and Raman shifts were closely related to the thickness of the SnS2 nanoflakes. Moreover, photoconductive AFM was performed on the monolayer-stepped SnS2 nanoflakes, revealing that the flat surface and the edges of the SnS2 atomic steps had different electrical conductive properties and photoconductive behaviors. This is ascribed to the dangling bonds and defects at the atomic step edges, which caused a height difference of the Schottky barriers formed at the interfaces between the PtIr-coated AFM tip and the step edges or the flat surface of the SnS2 nanoflakes. The 2D SnS2 crystals with regular monolayer atomic steps and fast photoresponsivity are promising for novel applications in photodetectors and integrated optoelectronic circuits.

Considerable efforts have been devoted on the design and fabrication of non-platinum electrocatalysts with high performance and low cost for hydrogen evolution reaction (HER). However, the catalytic activity of existing electrocatalysts usually subjects to the limited amount of exposed active sites. Herein, we propose that self-assembled ultrathin NiCo2S4 nanoflakes grown on nickel foam (NiCo2S4/Ni foam) can serve as excellent electrocatalyst for HER in alkaline solution with high activity and stability. The NiCo2S4/Ni foam electrodes were prepared by the complete sulfidation of networked ultrathin NiCo-layered double hydroxide nanoflakes grown on Ni foam (NiCo-LDH/Ni foam). The advantages of this unique architecture are that the ultrathin and porous NiCo2S4 nanoflakes can provide a huge number of exposed active sites, the highly-conductive Ni foam can promote the transfer of electrons, and the three-dimensional-networked structure can facilitate the diffusion and penetration of electrolyte. Electrochemical measurements reveal that NiCo2S4/Ni foam electrodes exhibit greatly improved performance than NiCo-LDH/Ni foam for HER in alkaline solution with low onset overpotential (17 mV), small Tafel slope (84.5 mV/dec) and excellent long-duration cycling stability (maintaining an onset overpotential of ~20 mV and an overpotential of 155 mV at 50 mA/cm2 after testing for 100,000 s). In addition, the highly-flexible NiCo2S4/Ni foam electrodes show no obvious catalytic degradation after bending for 200 times, confirming the high flexibility and robustness under severe conditions.

Molecularly imprinted poly(hydroxyethyl methacrylate) microspheres (PHEMA MIPMs) were prepared via precipitation polymerization in this article, using gatifloxacin (GFLX), hydroxyethyl methacrylate (HEMA), and ethylene glycol dimethacrylate (EGDMA) as template molecule, functional monomer and cross-linker, respectively. The effects of reaction medium, initial total monomers, cross-linker and molecular imprinting on the polymerization were investigated systematically. The interaction between GFLX and HEMA in pre-solution was studied by UV–Visible spectrophotometer, both size and morphology of products were characterized by a scanning electron microscope. When the total initial monomer concentration was 1 vol%, EGDMA content was 70 mol%, a group of uniform PHEMA MIPMs were prepared at different GFLX/MAA molar ratios, with diameter range from 2.06 ± 0.07 to 2.82 ± 0.20 μm. The results of drug loading and in vitro release experiments demonstrated that PHEMA MIPMs could achieve a higher GFLX loading content and a more acceptable sustained release than non-imprinted ones.

Practical teaching is the key to the development of vocational education, is the “core” and “breakthrough” of higher vocational education personnel training mode reform. And the construction of practical training base is the premise and guarantee of training education, China's higher vocational education training base construction after years of groping, what problems still exist, what new problems are developed, how to deal with these problems is very important.