Particulate matter (PM) pollutants, including nanoscale particles (NPs), have been considered serious threats to public health. In this work, a self-powered air filter that can be used in ...high-efficiency removal of PM, including NPs, is presented. An ionic liquid-polymer (ILP) composite is irregularly distributed onto a sponge network to form an ILP@MF filter. Enabled by its unique electrochemical properties, the ILP@MF filter can remove PM
and PM
with high efficiencies of 99.59% and 99.75%, respectively, after applying a low voltage. More importantly, the charged ILP@MF filter realizes a superior removal for NPs with an efficiency of 93.77%. A micro-button lithium cell or silicon-based solar panel is employed as a power supply platform to fabricate a portable and self-powered face mask, which exhibits excellent efficacy in particulate removal compared to commercial masks. This work shows a great promise for high-performance purification devices and facile mask production to remove particulate pollutants.
Abstract
The delivery of alkyl radicals through photocatalytic deoxygenation of primary alcohols under mild conditions is a so far unmet challenge. In this report, we present a one-pot strategy for ...deoxygenative Giese reaction of alcohols with electron-deficient alkenes, by using xanthate salts as alcohol-activating groups for radical generation under visible-light photoredox conditions in the presence of triphenylphosphine. The convenient generation of xanthate salts and high reactivity of sequential C–S/C–O bond homolytic cleavage enable efficient deoxygenation of primary, secondary and tertiary alcohols with diverse functionality and structure to generate the corresponding alkyl radicals, including methyl radical. Moreover, chemoselective radical monodeoxygenation of diols is achieved via selective formation of xanthate salts.
Administration of exosomes derived from mesenchymal stromal cells (MSCs) could improve some neurologic conditions by transferring functional biomolecules to recipient cells. Furthermore, exosomes ...from hypoxic progenitor cells exerted better therapeutic effects in organ injury through specific cargoes. However, there are no related reports about whether exosomes derived from MSCs or hypoxia‐preconditioned MSCs (PC‐MSCs) could prevent memory deficits in Alzheimer disease (AD). In this study, the exosomes derived from MSCs or PC‐MSCs were systemically administered to transgenic APP/PS1 mice. The expression of miR‐21 in MSCs was significantly increased after hypoxic treatment. Injection of exosomes from normoxic MSCs could rescue cognition and memory impairment according to results of the Morris water maze test, reduced plaque deposition, and Aβ levels in the brain; could decrease the activation of astrocytes and microglia; could down‐regulate proinflammatory cytokines (TNF‐α and IL‐1β); and could up‐regulate anti‐inflammatory cytokines (IL‐4 and ‐10) in AD mice, as well as reduce the activation of signal transducer and activator of transcription 3 (STAT3) and NF‐κB. Compared to the group administered exosomes from normoxic MSCs, in the group administered exosomes from PC‐MSCs, learning and memory capabilities were significantly improved; the plaque deposition and Aβ levels were lower, and expression of growth‐associated protein 43, synapsin 1, and IL‐10 was increased; and the levels of glial fibrillary acidic protein, ionized calcium‐binding adaptor molecule 1, TNF‐α, IL‐1β, and activation of STAT3 and NF‐κB were sharply decreased. More importantly, exosomes from PC‐MSCs effectively increased the level of miR‐21 in the brain of AD mice. Additionally, replenishment of miR‐21 restored the cognitive deficits in APP/PS1 mice and prevented pathologic features. Taken together, these findings suggest that exosomes from PC‐MSCs could improve the learning and memory capabilities of APP/PS1 mice, and that the underlying mechanism may lie in the restoration of synaptic dysfunction and regulation of inflammatory responses through regulation of miR‐21.—Cui, G.‐H., Wu, J., Mou, F.‐F., Xie, W.‐H., Wang, F.‐B., Wang, Q.‐L., Fang, J., Xu, Y.‐W., Dong, Y.‐R., Liu, J.‐R., Guo, H.‐D. Exosomes derived from hypoxia‐preconditioned mesenchymal stromal cells ameliorate cognitive decline by rescuing synaptic dysfunction and regulating inflammatory responses in APP/PS1 mice. FASEB J. 32, 654–668 (2018). www.fasebj.org
Along with the development of nuclear power, concerns about radioactive emissions and the potential for nuclear leakage have been widely raised, particularly of harmful iodine isotopes. However, as a ...significant component of nuclear air waste, the enrichment and detection of air‐dispersed gaseous iodine remain a challenge. In this work, it is focused on developing an attraction‐immobilization‐detection strategy‐based fluorescence method for the on‐site detection of volatile iodine, by employing a photoluminescent ionic polyimine network‐polyvinylpyrrolidone (IPIN‐PVP) composite membrane. This strategy synergizes ion‐induced dipole interactions from IPIN and complexation effects from PVP, allowing effective iodine enrichment and immobilization. As a result, the optimized IPIN‐PVP membrane exhibits rapid response times of 5 s and a low detection limit of 4.087 × 10−8 m for gaseous iodine. It also introduces a portable handheld detection device that utilizes the composite membrane, offering a practical solution for real‐time on‐site detection of volatile iodine. This innovation enhances nuclear safety measures and disaster management by providing rapid and reliable iodine detection capabilities.
Concerns about radioactive iodine emissions and the potential for nuclear leakage are raised. Herein, a fluorescence‐based method using an ionic polyimine network‐polyvinylpyrrolidone composite membrane is developed for on‐site detection of volatile iodine, by utilizing ion‐induced dipole interactions and complexation effects for iodine enrichment and immobilization. The resulting membrane shows rapid response time and low detection limit.
A novel low‐symmetry organic molecular cage with distinctive geometry was successfully synthesized from 5,5′‐(propane‐2,2‐diyl)bis(2‐hydroxyisophthalaldehyde) and 1,2‐cyclohexanediamine building ...blocks, through the desymmetrized vertex design strategy. Single‐crystal X‐ray crystallographic analysis shows that the cage contains asymmetrical and nonplanar windows, exhibiting an unprecedented C2 symmetry and an efficient packing. The molecular cage structure was also characterized by FTIR, NMR, and MALDI‐TOF. Quantum chemistry studies show that the cage structure contains rare intramolecular hydrogen‐hydrogen (C−H⋅⋅⋅H−C) bonding interactions. The cage crystals exhibit high iodine vapor uptake (3.78 g g−1), which is among the highest for porous molecular materials. The knowledge gained in this study would open new possibilities for the design and synthesis of molecular cages with novel topologies targeting a broad range of applications.
A low‐symmetry organic molecular cage with distinctive geometry was successfully synthesized through the desymmetrized vertex design strategy.
Wearable devices and systems demand multifunctional units with intelligent and integrative functions. Smart fibers with response to external stimuli, such as electrical, thermal, and photonic ...signals, etc., as well as offering energy storage/conversion are essential units for wearable electronics, but still remain great challenges. Herein, flexible, strong, and self‐cleaning graphene‐aerogel composite fibers, with tunable functions of thermal conversion and storage under multistimuli, are fabricated. The fibers made from porous graphene aerogel/organic phase‐change materials coated with hydrophobic fluorocarbon resin render a wide range of phase transition temperature and enthalpy (0–186 J g−1). The strong and compliant fibers are twisted into yarn and woven into fabrics, showing a self‐clean superhydrophobic surface and excellent multiple responsive properties to external stimuli (electron/photon/thermal) together with reversible energy storage and conversion. Such aerogel‐directed smart fibers promise for broad applications in the next‐generation of wearable systems.
A variety of multiresponsive smart fibers with a wide range of tunable phase transition temperatures and enthalpy are produced through impregnation of different types of organic phase‐change materials into graphene aerogel fibers and finished by coating a fluorocarbon resin layer, showing a self‐cleaning superhydrophobic surface and excellent multiple‐responsive properties to external stimuli (electron/photon/thermal) together with reversible energy storage and conversion.
Adsorption, storage, and conversion of gases (e.g., carbon dioxide, hydrogen, and iodine) are the three critical topics in the field of clean energy and environmental mediation. Exploring new methods ...to prepare high-performance materials to improve gas adsorption is one of the most concerning topics in recent years. In this work, an ionic liquid solution process (ILSP), which can greatly improve the adsorption kinetic performance of covalent organic framework (COF) materials for gaseous iodine, is explored. Anionic COF TpPaSO
H is modified by amino-triazolium cation through the ILSP method, which successfully makes the iodine adsorption kinetic performance (K
rate) of ionic liquid (IL) modified COF AC
tirmTpPaSO
quintuple compared with the original COF. A series of experimental characterization and theoretical calculation results show that the improvement of adsorption kinetics is benefited from the increased weak interaction between the COF and iodine, due to the local charge separation of the COF skeleton caused by the substitution of protons by the bulky cations of ILs. This ILSP strategy has competitive help for COF materials in the field of gas adsorption, separation, or conversion, and is expected to expand and improve the application of COF materials in energy and environmental science.
The strong π-π interactions in the stacking layers of two-dimensional covalent organic frameworks (2D-COFs), together with rotationally labile imine linkages, make most of the solid state ...imine-linked COFs non-fluorescent due to fluorescence quenching processes. Here, we report the successful synthesis of highly photoluminescent imine-based 2D-COFs by integrating a non-planar building unit with a pyrene-based unit and transforming the COF into spherical, sub-micron particles. High photoluminescence quantum yields (PLQY) were achieved with COF sub-micron particles dispersed in organic solvents. The as-prepared COF sub-micron particles can be used as a chemical sensor for the detection of explosive chemicals, with high sensitivity and selectivity (up to ppm level).
The removal of C2H2 and C2H6 from C2H4 streams is of great significance for feedstock purification to produce polyethylene and other commodity chemicals but the simultaneous adsorption of C2H6 and ...C2H2 over C2H4 from a ternary mixture has never been realized. Herein, a robust metal–organic framework, TJT‐100, was designed and synthesized, which demonstrates remarkably selective adsorption of C2H2 and C2H6 over C2H4. Breakthrough experiments show that TJT‐100 can be used as an adsorbent for high‐performance purification of C2H4 from a ternary mixture of C2H2/C2H4/C2H6 (0.5:99:0.5) to afford a C2H4 purity greater than 99.997 %, beyond that required for ethylene polymerization. Computational studies reveal that the uncoordinated carboxylate oxygen atoms and coordinated water molecules pointing towards the pore can trap C2H2 and C2H6 through the formation of multiple C−H⋅⋅⋅O electrostatic interactions, while the corresponding C2H4–framework interaction is unfavorable.
A robust porous metal–organic framework was synthesized and utilized for the highly selective separation of C2H4 from a ternary mixture of C2 hydrocarbons. After a single operation, the C2H4 purity of the outlet was greater than 99.997 %.
Among the d10 coinage metal complexes, cyclic trinuclear complexes (CTCs) or trinuclear metallocycles with intratrimer metal–metal interactions are fascinating and important metal–organic or ...organometallic π-acids/bases. Each CTC of characteristic planar or near-planar trimetal nine-membered rings consists of Au(I)/Ag(I)/Cu(I) cations that linearly coordinate with N and/or C atoms in ditopic anionic bridging ligands. Since the first discovery of Au(I) CTC in the 1970s, research of CTCs has involved several fundamental areas, including noncovalent and metallophilic interaction, excimer/exciplex, acid–base chemistry, metalloaromaticity, supramolecular assemblies, and host/guest chemistry. These allow CTCs to be embraced in a wide range of innovative potential applications that include chemical sensing, semiconducting, gas and liquid adsorption/separation, catalysis, full-color display, and solid-state lighting. This review aims to provide a historic and comprehensive summary on CTCs and their extension to higher nuclearity complexes and coordination polymers from the perspectives of synthesis, structure, theoretical insight, and potential applications.