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Low-cost and biodegradable photothermal wound dressings with remarkable therapeutic effects are highly desirable for next-generation wound healing. Herein, we report an efficient photothermal wound dressing mat made of tellurium nanosheet (TeNS)-loaded electrospun polycaprolactone/gelatin (PCL/GEL) nanofibers. The TeNS-loaded PCL/GEL nanofibrous architectures showed antibacterial efficacy against Escherichia coli and Staphylococcus aureus of 87.68% and 94.57%, respectively. Under near-infrared (NIR) light illumination, they can facilitate cell proliferation as revealed by in vitro scratch assay. The results from in vivo skin wounds combined with tissue staining experiments further showed that the TeNS-loaded dressing could substantially promote wound healing under photothermal conditions. Using immunohistochemical analysis, we found that the TeNS-loaded PCL/GEL nanofibers $+$ NIR group have a high expression of specific antigens in epidermal growth factor (EGF) ($P<0.01$) and endothelial cell adhesion molecule-31 (CD31, $P<0.05$), verifying that the nanofibrous mat can stimulate EGF generation and microvessel proliferation. Furthermore, the PCL/GEL/Te$+$NIR group has the lowest expression in endothelial cell adhesion molecule-68 (CD68, $P<0.01$), suggesting that the nanofibrous mats have a high anti-inflammatory efficiency. Our work sheds light on the development of novel nonanti-inflammatory wound dressings via photothermal sterilization and the promotion of cell growth using two-dimensional (2D) nanosheets.

Recent advances in the chemistry of main group porphyrin complexes are surveyed. New, unprecedented structural types for porphyrin complexes which have been revealed from the recent reports of boron and tellurium porphyrins are described. Advances in the preparation and reactivity of Group 14 (silicon and tin) and Group 15 porphyrin complexes are discussed. A systematic variation in the out-of-plane distortion (ruffling) of light element Group 14 and 15 porphyrin complexes has become apparent now that a significant number of structurally characterized examples are at hand.

Knowledge of distribution coefficient values is essential in estimating the refining efficiency, and plays an important role during the purification process, typically zone refining. The effective distribution coefficient "K_eff" of impurities Se, Fe, Cr and Pb in tellurium was determined in the present study and found to be 0.48, 0.05, 0.25 and 0.19, respectively. The results are validated by comparing with the available published data, and we observed a difference of less than one order, which was reasonably comparable. The influence of "K_eff" on zone refining efficiency was examined and it was noticed that the effective distribution coefficient increases with respect to the translation rate, which is minimum at an optimum lower translation rate (= 30 mm/h). The relative solute concentration C/C₀ is determined experimentally, which shows the best fit of experimental values with Pfann's equation. The impurity profile along the length of the zone refined ingot is also discussed.

An expanded heterocorrole, meso-tetraaryl-tellura[22]porphyrin(6.1.1.0), containing a bipyrrole moiety and a six-carbon long link, has been synthesized. The reaction path proceeds through a controlled acid-promoted extrusion of one tellurium atom from meso-aryl-26,28-ditellurasapphyrin, leading to a structure where one tellurophene ring of the substrate is replaced by a bridging acyclic four-carbon unit. This aromatic porphyrin-annulene hybrid is conformationally flexible in solution, on account of the C₄ unit adopting two different configurations: trans–cis–trans or all-trans. Studies of the dynamic behavior of tellura[22]porphyrin(6.1.1.0) in solution were performed by means of ¹H and ¹²⁵Te NMR spectroscopy. The X-ray structure of the all-trans form with trapezoid macrocyclic skeleton is also presented.

The normal states of simple elemental metal and complex compound superconductors have been studied by using first principle methods and model analysis. The flat/steep band electronic structure and the peak-like structure of electron-phonon coupling have been found as two universal characteristics. A new Hamiltonian is proposed to describe the electronic structure of insulating solids.