Hydrothermal Synthesis g‑C₃N₄/Nano-InVO₄ Nanocomposites and Enhanced Photocatalytic Activity for Hydrogen Production under Visible Light Irradiation

We synthesized g-C₃N₄/nano-InVO₄ heterojunction-type photocatalyts by in situ growth of InVO₄ nanoparticles onto the surface of g-C₃N₄ sheets via a hydrothermal process. The results of SEM and TEM showed that the obtained InVO₄ nanoparticles 20 nm in size dispersed uniformly on the surface of g-C₃N₄ sheets, which revealed that g-C₃N₄ sheets was probably a promising support for in situ growth of nanosize materials. The achieved intimate interface promoted the charge transfer and inhibited the recombination rate of photogenerated electron–hole pairs, which significantly improved the photocatalytic activity. A possible growth process of g-C₃N₄/nano-InVO₄ nanocomposites was proposed based on different mass fraction of g-C₃N₄ content. The obtained g-C₃N₄/nano-InVO₄ nanocomposites could achieve effective separation of charge-hole pairs and stronger reducing power, which caused enhanced H₂ evolution from water-splitting compared with bare g-C₃N₄ sheets and g-C₃N₄/micro-InVO₄ composites, respectively. As a result, the g-C₃N₄/nano-InVO₄ nanocomposite with a mass ratio of 80:20 possessed the maximum photocatalytic activity for hydrogen production under visible-light irradiation

Heterogeneous fluid flow in fractured layered carbonates and its implication for generation of incipient karst

We use numerical models to investigate fluid flow in layered fractured carbonate rocks, and specifically to investigate the effects of the structural and hydraulic properties of both joints and bedding planes on flow localization. Synthetic fracture networks made up of two jointed layers separated by a horizontal bedding plane are generated to represent the typical layered fracture systems often formed in carbonate rocks. A uniform aperture field is assumed for each joint set and for the bedding plane, but different joint sets and the bedding plane can have non-identical values. The aperture ratio of the joint sets to the bedding plane is found to dominate the behaviour of flow heterogeneity on the bedding plane. Three distinct flow regimes, i.e. joint-dominated, transitional and bedding plane-dominated, are recognized. The magnitude of the aperture ratio controls which flow regime develops. We further suggest that the different flow regimes may be responsible for the initiation of different types of incipient karst morphologies observed in nature: pipe karst, stripe karst and sheet karst

Monitoring plasmon coupling and SERS enhancement through in situ nanoparticle spacing modulation

Self-assembled nanoparticle (NP) arrays at liquid interfaces provide a unique optical response which has opened the door to new tuneable metamaterials and for sensing and optical applications. NPs can spontaneously assemble at the liquid-liquid interface, forming an ordered, self-healing, low-defect 2D film. The close proximity of the NPs at the interface results in collective plasmonic modes with a spectral response dependent on the distance between the NPs and induces large field enhancements within the gaps. In this study, we assembled spherical and rod-shaped gold NPs with the aim of improving our understanding of NP assembly processes at liquid interfaces, working towards finely controlling their structure and producing tailored optical and enhanced Raman signals. We systematically tuned the assembly and spacing between NPs through increasing or decreasing the degree of electrostatic screening between NPs with the addition of electrolyte or pH adjustment. The in situ modulation of nanoparticle positioning on the same sample allowed us to monitor plasmon coupling and the resulting SERS enhancement processes in real time, with sub-nm precision

Engineered Multifunctional Zinc–Organic Framework-Based Aggregation-Induced Emission Nanozyme for Accelerating Spinal Cord Injury Recovery

Functional recovery following a spinal cord injury (SCI) is challenging. Traditional drug therapies focus on the suppression of immune responses; however, strategies for alleviating oxidative stress are lacking. Herein, we developed the zinc–organic framework (Zn@MOF)-based aggregation-induced emission–active nanozymes for accelerating recovery following SCI. A multifunctional Zn@MOF was modified with the aggregation-induced emission–active molecule 2-(4-azidobutyl)-6-(phenyl(4-(1,2,2-triphenylvinyl)phenyl)amino)-1H-phenalene-1,3-dione via a bioorthogonal reaction, and the resulting nanozymes were denoted as Zn@MOF-TPD. These nanozymes gradually released gallic acid and zinc ions (Zn2+) at the SCI site. The released gallic acid, a scavenger of reactive oxygen species (ROS), promoted antioxidation and alleviated inflammation, re-establishing the balance between ROS production and the antioxidant defense system. The released Zn2+ ions inhibited the activity of matrix metalloproteinase 9 (MMP-9) to facilitate the regeneration of neurons via the ROS-mediated NF-κB pathway following secondary SCI. In addition, Zn@MOF-TPD protected neurons and myelin sheaths against trauma, inhibited glial scar formation, and promoted the proliferation and differentiation of neural stem cells, thereby facilitating the repair of neurons and injured spinal cord tissue and promoting functional recovery in rats with contusive SCI. Altogether, this study suggests that Zn@MOF-TPD nanozymes possess a potential for alleviating oxidative stress-mediated pathophysiological damage and promoting motor recovery following SCI

Additional file 8: Table S4. of Analysis of the genomic sequences and metabolites of Serratia surfactantfaciens sp. nov. YD25T that simultaneously produces prodigiosin and serrawettin W2

The less than 98.7 % 16S rRNA gene sequence similarities between YD25T and type strains of phylogenetically related species. (DOCX 12 kb

Additional file 11: Figure S6. of Analysis of the genomic sequences and metabolites of Serratia surfactantfaciens sp. nov. YD25T that simultaneously produces prodigiosin and serrawettin W2

Neighbor-joining tree showing the phylogenetic relationships of YD25T and phylogenetically related reference strains based on rpoB gene sequences. Bootstrap analysis (1000 resamplings) was used to evaluate the topology of the NJ tree, and the bootstrap values > 50 % are displayed at branch points. Bar, 0.01 substitutions per nucleotide position. (DOCX 148 kb