Репозиторий Университета

© 2021 Elsevier B.V. In this work, pristine Cu2O and Au nanoparticle modified Cu2O (Au/Cu2O) spherical nanocomposites were prepared by a simple redox method at room temperature. The as-prepared Cu2O nanospheres with diameters of 150–200 nm show relatively large surface area. The dye removal abilities of the pure Cu2O and the Au/Cu2O nanocomposites were tested by evaluating their adsorption and photocatalytic activities towards different aromatic molecules (e.g., Congo red (CR), Methyl orange (MO), Methyl blue (MB), Rhodamine B (RhB)). The experimental results indicate that the Au/Cu2O nanocomposites exhibit much superior adsorption and photocatalytic properties to the pristine Cu2O nanospheres. Among the catalysts, 1 wt% Au/Cu2O nanocomposite shows the best removal abilities to various dyes. Besides, the removal abilities towards these dyes are quite different from each other. For deep understanding of the adsorption mechanism, molecular dynamics (MD) caculations were conducted to investigate the adsorption energy of the Cu2O spheres by simulating the porous structure and Au modification. The calculation results indicate that CR and MO are chemically adsorbed on the Cu2O materials while the adsorption of MB and RhB are physical adsorption, which are well consistent with the experimental results. This study demonstrates the porous Cu2O based nanocomposites are promising materials with high adsorption and solar light-photocatalytic performance. In the meanwhile, the underlying mechanism on the superior dye removal abilities of Au modified Cu2O nanospheres were systematically discussed.

© 2018 Elsevier Ltd The space-filling fibrin network is a major part of clots and thrombi formed in blood. Fibrin polymerization starts when fibrinogen, a plasma protein, is proteolytically converted to fibrin, which self-assembles to form double-stranded protofibrils. When reaching a critical length, these intermediate species aggregate laterally to transform into fibers arranged into branched fibrin network. We combined multiscale modeling in silico with atomic force microscopy (AFM) imaging to reconstruct complete atomic models of double-stranded fibrin protofibrils with γ-γ crosslinking, A:a and B:b knob-hole bonds, and αC regions—all important structural determinants not resolved crystallographically. Structures of fibrin oligomers and protofibrils containing up to 19 monomers were successfully validated by quantitative comparison with high-resolution AFM images. We characterized the protofibril twisting, bending, kinking, and reversibility of A:a knob-hole bonds, and calculated hydrodynamic parameters of fibrin oligomers. Atomic structures of protofibrils provide a basis to understand mechanisms of early stages of fibrin polymerization. Zhmurov et al. used 27 relevant crystal structures to computationally reconstruct the full-atomic models of fibrin oligomers and protofibrils, which correlate with high-resolution atomic force microscopy images. The structures contain much valuable information for understanding the early stages of fibrin polymerization.