Axial Mn–C_CN Bonds of Cyano Manganese(II) Porphyrin Complexes: Flexible and Weak?

Three five-coordinate high-spin (cyano)­manganese­(II) complexes, utilized tetraphenylporphyrin (TPP), tetratolylporphyrin (TTP), and tetramesitylporphyrin (TMP) as ligands, are prepared and studied by single-crystal X-ray, FT-IR, UV–vis, and EPR spectroscopies. The crystal structure studies revealed noteworthy structural features including unexpectedly wide tilting angles of the axial Mn–C_CN bonds, which is contrasted to the isoelectronic Fe­(III)–C_CN bonds. Solid-state EPR measurements (90 K) and simulations are applied to obtain the ZFS parameters (<i>D</i>, <i>E</i>, and <i>E</i>/<i>D</i> (λ)), which are compared to Mn­(II) porphyrin analogues of hemes to understand the ligand field of the cyanide. The solution EPR studies gave new insights into the chemical equilibrium of four- and five-coordinate species, which has been monitored by UV–vis spectroscopy

Unique Axial Imidazole Geometries of Fully Halogenated Iron(II) Porphyrin Complexes: Crystal Structures and Mössbauer Spectroscopic Studies

The synthesis and characterization of several electron-poor iron­(II) porphyrin (FeTFPPBr8) complexes with axial imidazole ligands are reported. The single-crystal X-ray structures have been studied by a combination of crystal packing and Hirshfeld surface calculations, which explained the unusual axial-ligand geometries, e.g., the strong tilt of the Fe–NIm bonds and the imidazole planes. The six-coordinate [Fe­(TFPPBr8)­(1-MeIm)2] was studied by multiple-temperature solid-state Mössbauer spectroscopy, which suggested that it is a low-spin complex with δ ∼ 0.32–0.38 mm/s and ΔEQ ∼ 1.0 mm/s

Unique Axial Imidazole Geometries of Fully Halogenated Iron(II) Porphyrin Complexes: Crystal Structures and Mössbauer Spectroscopic Studies

The synthesis and characterization of several electron-poor iron­(II) porphyrin (FeTFPPBr8) complexes with axial imidazole ligands are reported. The single-crystal X-ray structures have been studied by a combination of crystal packing and Hirshfeld surface calculations, which explained the unusual axial-ligand geometries, e.g., the strong tilt of the Fe–NIm bonds and the imidazole planes. The six-coordinate [Fe­(TFPPBr8)­(1-MeIm)2] was studied by multiple-temperature solid-state Mössbauer spectroscopy, which suggested that it is a low-spin complex with δ ∼ 0.32–0.38 mm/s and ΔEQ ∼ 1.0 mm/s

Unique Axial Imidazole Geometries of Fully Halogenated Iron(II) Porphyrin Complexes: Crystal Structures and Mössbauer Spectroscopic Studies

The synthesis and characterization of several electron-poor iron­(II) porphyrin (FeTFPPBr8) complexes with axial imidazole ligands are reported. The single-crystal X-ray structures have been studied by a combination of crystal packing and Hirshfeld surface calculations, which explained the unusual axial-ligand geometries, e.g., the strong tilt of the Fe–NIm bonds and the imidazole planes. The six-coordinate [Fe­(TFPPBr8)­(1-MeIm)2] was studied by multiple-temperature solid-state Mössbauer spectroscopy, which suggested that it is a low-spin complex with δ ∼ 0.32–0.38 mm/s and ΔEQ ∼ 1.0 mm/s

Unique Axial Imidazole Geometries of Fully Halogenated Iron(II) Porphyrin Complexes: Crystal Structures and Mössbauer Spectroscopic Studies

The synthesis and characterization of several electron-poor iron­(II) porphyrin (FeTFPPBr₈) complexes with axial imidazole ligands are reported. The single-crystal X-ray structures have been studied by a combination of crystal packing and Hirshfeld surface calculations, which explained the unusual axial-ligand geometries, e.g., the strong tilt of the Fe–N_Im bonds and the imidazole planes. The six-coordinate [Fe­(TFPPBr₈)­(1-MeIm)₂] was studied by multiple-temperature solid-state Mössbauer spectroscopy, which suggested that it is a low-spin complex with δ ∼ 0.32–0.38 mm/s and Δ<i>E</i>_Q ∼ 1.0 mm/s

Graphene Oxide Membranes with Conical Nanochannels for Ultrafast Water Transport

Membrane-based separations have been increasingly utilized to address global energy crisis and water scarcity. However, the separation efficiency often suffers from the trade-off between membrane permeability and selectivity. Although great efforts have been devoted, a membrane with both high permeability and high selectivity remains a distant prospect. Inspired by the hourglass structure and ultrafast water transport in aquaporins, we propose a novel approach to fabricating membranes with conical nanochannels to reduce the mass transfer resistance and to introduce Laplace pressure as the internal driving force, which successfully breaks the permeability/selectivity trade-off. First, sulfonated polyaniline (SPANI) nanorods were in situ-synthesized and vertically aligned on sulfonated graphene oxide (SGO) nanosheets, forming SGO–SPANIX composites. Then, the graphene oxide (GO) membranes were fabricated by assembling SGO–SPANIX composites through pressure-assisted filtration, in which the SPANI nanorods would bend and flatten on the SGO nanosheets under low shear force, forming stripe arrays on SGO nanosheets. The tilted stripe arrays between the adjacent SGO nanosheets form the conical nanochannels inside GO membranes. The conical nanochannels significantly decreased the steric hindrance and enabled the generation of Laplace pressure as the internal driving force within membranes. Consequently, the resulting membranes exhibit an ultrahigh water permeability of 1222.77 L·m–2·h–1·bar–1 and high efficiency in dye removal from water with a rejection of 90.44% and permeability of 528 L·m–2·h–1·bar–1

Asymmetric Aerogel Membranes with Ultrafast Water Permeation for the Separation of Oil-in-Water Emulsion

Owing to highly porous and low density attributes, aerogels have been actively utilized in catalysis and adsorption processes, but their great potential in filtration requires exploitation. In this study, an asymmetric aerogel membrane is fabricated via one-pot hydrothermal reaction-induced self-cross-linking of poly­(vinyl alcohol) (PVA), which exhibits ultrafast permeation for the separation of oil-in-water emulsion. Meanwhile, carbon nanotubes are added to improve the mechanical strength of the aerogel membranes. The self-cross-linking of PVA forms the supporting layer, and the exchange of water and vapor at the interface of PVA solution and air generates the separating layer as well as abundant hydroxyl groups on the membrane surface. The density, porosity, pore size, and wettability of the aerogel membrane can be tuned by the PVA concentration. Owing to high porosity (>95%) and suitable pore size (<85 nm), the aerogel membrane exhibits high rejection (99.0%) for surfactant-stabilized oil-in-water emulsion with an ultrahigh permeation flux of 135.5 × 10³ L m^–2 h^–1 bar^–1 under gravity-driven flow, which is 2 orders of magnitude higher than commercial filtration membranes with similar rejection. Meanwhile, the aerogel membrane exhibits superhydrophilicity, superoleophobicity underwater, and excellent antifouling properties for various surfactant-stabilized oil-in-water emulsions, as indicated by the fact that the flux recovery ratio maintains more than 93% after five cycles of the filtration experiment. The findings in this study may offer a novel idea to fabricate high-throughput filtration membranes

Image_1_Interleukin-10 Promotes Porcine Circovirus Type 2 Persistent Infection in Mice and Aggravates the Tissue Lesions by Suppression of T Cell Infiltration.tif

Interleukin (IL)-10, as a key anti-inflammatory cytokine, increases during porcine circovirus type 2 (PCV2) infection, but the role of IL-10 in the process remains to be defined. In the present study, using an IL-10 deficient mice model, we found that IL-10 deficiency prevented the reduction of splenic lymphocytes (CD45+ cells) induced by PCV2 and promoted CD4+ and CD8+ T cell infiltration in lungs through inducting more T cell chemokines (CCL3, CXCL9, and CXCL10). Simultaneously, PCV2 infection induced a significant increase of pro-inflammatory cytokines and PCV2-specific antibodies in IL-10 deficient mice than in wild-type mice, resulting in a lower viral load in lung and a milder lung lesion in IL-10 deficient mice relative to wild-type mice. Moreover, the amounts of pulmonary CD4+ and CD8+ T cells were all inversely correlated with the lung lesions, as well as the viral load of PCV2. These results demonstrate that PCV2 infection employs IL-10 to block the transfer of T cells to the lungs of mice, and IL-10 attenuates the production of pro-inflammatory cytokines and PCV2-specific antibodies. The lack of T cell infiltration, pro-inflammatory cytokines, and PCV2-specific antibodies promote PCV2 replication, leading to a more severe lung lesion in mice.</p

Enhanced Mono/Divalent Ion Separation via Charged Interlayer Channels in Montmorillonite-Based Membranes

Efficient mono- and divalent ion separation is pivotal for environmental conservation and energy utilization. Two-dimensional (2D) materials featuring interlayer nanochannels exhibit unique water and ion transport properties, rendering them highly suitable for water treatment membranes. In this work, we incorporated polydopamine/polyethylenimine (PDA/PEI) copolymers into 2D montmorillonite (MMT) nanosheet interlayer channels through electrostatic interactions and bioinspired bonding. A modified laminar structure was formed on the substrate surface via a straightforward vacuum filtration. The electrodialysis experiments reveal that these membranes could achieve monovalent permselectivity of 11.06 and Na+ flux of 2.09 × 10–8 mol cm–2 s–1. The enhanced permselectivity results from the synergistic effect of electrostatic and steric hindrance effect. In addition, the interaction between the PDA/PEI copolymer and the MMT nanosheet ensures the long-term operational stability of the membranes. Theoretical simulations reveal that Na+ has a lower migration energy barrier and higher migration rate for the modified MMT-based membrane compared to Mg2+. This work presents a novel approach for the development of monovalent permselective membranes

Self-standing 3D core-shell nanohybrids based on amorphous Co-Fe-Bi nanosheets grafted on NiCo2O4 nanowires for efficient and durable water oxidation

Here, a three-dimensional (3D) core–shell nanohybrid based on few-layer amorphous Co–Fe–Bi nanosheets directly grown on crystalline NiCo2O4 nanowires supported on the Ni foam (Co–Fe–Bi/NiCo2O4/NF) are facilely fabricated as highly efficient and durable electrocatalysts for water oxidation. This self-standing 3D core–shell nanohybrid design with unique materials chemistry and excellent interface engineering enhances the mass transport and stimulates the production of active sites during the oxygen evolution reaction. Serving as the anode catalysts, the resulting self-standing Co–Fe–Bi/NiCo2O4/NF nanohybrid electrocatalysts show a better electrocatalytic activity with an overpotential of 227 mV at 10 mA/cm2, a Tafel slope of 45 mV dec–1, excellent durability over 40 h, and the ability to deliver a current density of 200 mA/cm2 at an overpotential of ∼410 mV in an alkaline medium. Thus, the excellent electrocatalytic performance of the Co–Fe–Bi/NiCo2O4/NF nanohybrid demonstrates the importance of design and development of core–shell nanohybrids for large-scale practical applications in a multitude of energy conversion devices