Search

Solid polymer electrolytes (SPEs) have garnered extensive attention as potential alternatives to traditional liquid electrolytes, primarily due to their prowess in curbing lithium dendrite formation and preventing electrolyte leaks. The quest for SPEs that are both mechanically robust and exhibit superior ionic conductivity has been vigorous. However, achieving a harmonious balance between these two attributes remains a significant challenge. In this study, we introduce a novel quasi‐solid electrolyte, ingeniously crafted from a poly(urethane‐urea) network, enriched with lithium salts and plasticizers. This innovative composition not only boasts remarkable toughness but also ensures commendable ionic conductivity. Our post‐gelation method yields gel polymer electrolytes that undergo rigorous evaluation, leading to an optimized version that stands out with its exceptional room‐temperature ionic conductivity (2.94×10−4 S cm−1) and outstanding toughness (11.9 MJ m−3). Moreover, it demonstrates a broad electrochemical window (4.73 V), remarkable stability across a 600‐hour cycle test, a high capacity retention exceeding 80 % after 100 cycles at 0.2 C, and a noteworthy self‐healing capability. This quasi‐solid polymer electrolyte emerges as a promising contender to replace current liquid electrolyte solutions. [ABSTRACT FROM AUTHOR]

In this paper, we report for the first time the successful formation of a covalent cross-linking structure between polyacrylic acid and polyamide 66 in an electrospun nanofiber membrane by the facilitated amidation reaction using N-Hydroxy-succinimide (NHS) and N-(3-Dimethylaminopropyl)-N'-ethyl-carbodiimide hydrochloride (EDC). The structure and properties of the fiber membrane are characterized using scanning electron microscopy, wide field X-ray diffraction and differential scanning calorimetry. The results show that the presence of the cross-linked structure not only affects the construction of the nanofiber network framework but also influences the pore size distribution and size of the fiber membrane surface, which in turn affects its retention of contaminants and water absorption performance. After modification, the cross-linked membranes exhibited a significant retention performance of up to 77% for methyl tert-butyl ether (MTBE) with a reduced pure water flux. Furthermore, after crosslinking, the fiber membrane has been strongly enhanced with more stable pH response behavior. [ABSTRACT FROM AUTHOR]

Extracorporeal circulation (ECC) catheters have potential to be blood compatible and could be used to prevent thrombotic occlusion. Here, we produced heparin-mimicking anticoagulation PVC tubing on a large scale by synthesizing a heparin-mimicking polymer (HMP) and co-extruding. The PVC@HMP catheter was evaluated using whole human blood in vitro, which indicated it could prevent plasma protein attachment, reduce platelet adhesion and activation, and inhibit coagulation factors (XII, XI, IX, and VIII). Moreover, the anticoagulation PVC tubing was assembled into extracorporeal circulation with a New Zealand rabbit model, manifesting excellent real-time antithrombogenic properties without systemic heparin anticoagulation in vivo. The rapid recovery of coagulation factors after operation further confirmed its superiority over heparin, which would not completely inactivate the activity of those coagulation factors (XII, XI, IX and VIII). In addition, the PVC@HMP-1 catheters remain patent after being implanted in rats for 28 days without apparent inflammation and mortality complications. The anticoagulation PVC tubes could be used to construct various systemic and integrative anticlotting biomedical devices, which would dramatically reduce the introduction of heparin into blood circulation, thus preventing side effects and promoting the development of heparin-free treatment. [ABSTRACT FROM AUTHOR]

Island-type petrochemical parks have gradually become the 'trend' in establishing new parks because of the security advantages brought by their unique geographical locations. However, due to the frequent occurrence of natural disasters and difficulties in rescue in island-type parks, an early warning model is urgently needed to provide a basis for risk management. Previous research on early warning models of island-type parks seldom considered the particularity. In this study, the early warning indicator system is used as the input parameter to construct the early warning model of an island-type petrochemical park based on the back propagation (BP) neural network, and an actual island-type petrochemical park was used as a case to illustrate the model. Firstly, the safety influencing factors were screened by designing questionnaires and then an early warning indicator system was established. Secondly, particle swarm optimization (PSO) was introduced into the improved BP neural network to optimize the initial weights and thresholds of the neural network. A total of 30 groups of petrochemical park data were taken as samples—26 groups as training samples and 4 groups as test samples. Moreover, the safety status of the petrochemical park was set as the output parameter of the neural network. The comparative analysis shows that the optimized neural network is far superior to the unoptimized neural network in evaluation indicators. Finally, the Zhejiang Petrochemical Co., Ltd., park was used as a case to verify the accuracy of the proposed early warning model. Ultimately, the final output result was 0.8324, which indicates that the safety status of the case park was "safer". The results show that the BP neural network introduced with PSO can effectively realize early warning, which is an effective model to realize the safety early warning of island-type petrochemical parks. [ABSTRACT FROM AUTHOR]

Polyamide 66 microporous membranes were prepared by cold non-solvent-induced phase separation using polyamide 66-formic acid-propylene carbonate as a ternary membrane-forming system. The formed membranes exhibited a special bicontinuous structure consisting of interglued spherical crystals or interlocked bundles of microcrystalline aggregates. The variation of the microporous structure under the influence of preparation conditions, solvent, aging time, and polymer concentration affects the comprehensive performance of the membranes. For example, the cold-induced operation and the use of different membrane-forming solvents contributed to the crystallization of polyamide 66, resulting in an increased contact angle of polyamide 66 membranes, obtaining a high resistance to contamination of up to 73.5%. Moreover, the formed membranes still have high mechanical strength. [ABSTRACT FROM AUTHOR]

Carboxymethyl chitosan (CMCS), as a water‐soluble, biocompatible, and biodegradable polymer, is an excellent carrier for a sustained drug delivery system. In this study, a amphiphilic carboxymethyl chitosan‐ursolic acid nano‐drug carrier modified by folic acid (FPCU) were prepared, and then the nano‐drug carrier wrapped another anticancer drug 10‐hydroxycamptothecin were self‐assembled into nanoparticles (FPCU/HCPT NPs). The FPCU/HCPT NPs had a suitable size, high drug loading efficiency of ursolic acid (6.4%) and 10‐hydroxycamptothecin (14.1%). The drug release study in vitro indicated that the nanoparticles have obviously sustained effect and pH sensitive behaviors, the drug release amount was higher at pH 5.5 than at pH 7.4. in vitro and in vivo study showed that the nanoparticles displayed a high antitumor efficiency to tumor cells compared with free drug. The nano delivery system as a carrier for ursolic acid (UA) and 10‐hydroxycamptothecin (HCPT) has good application prospects in cancer treatment. [ABSTRACT FROM AUTHOR]

2 9 Si Nuclear Magnetic Resonance (NMR) can measure the molecular structure of silicate in oilfield reinjection water. However, noise in 2 9 Si NMR spectra (NMRS) affects the determination of silicate molecular structure type. To solve this problem, a new peak fitting method (Two-step Greedy-Singular Spectrum Analysis-Gaussian Fitting Method, TSG-SSA-GFM) is proposed in this paper. This method first uses TSG to determine the embedding dimension, then uses SSA to determine the characteristic peak position. Finally, GFM is used to calculate the molar ratio of characteristic peaks. The results show that TSG can quickly determine the embedding dimension and reduce computation by at least 50% vs. the global ergodic method. The mean deviation of characteristic peak positions determined by SSA is 0.07 ppm, while Discrete Wavelet Transform (DWT) and Empirical Mode Decomposition (EMD) cannot determine characteristic peaks of 2 9 Si NMRS containing overlapping peak. The average R -squared of Gaussian fitting of 2 9 Si NMRS is 98.4% while Lorentzian is 90.6%. Therefore, this study provides an important method for quantitative analysis of 2 9 Si NMRS. [ABSTRACT FROM AUTHOR]

Organic solvent purification and molecular separation play a remarkable role in textile, petrochemical and pharmaceutical industries, which is usually an energy intensive process, e.g. high temperature-driven distillation or high pressure-driven organic solvent nanofiltration. Here, we provide a promising alternative solar-thermal evaporation for organic solvent recovery and purification, an economic and green technology due to the sustainability and inexhaustibility of solar energy. To achieve that, cubic Prussian blue (PB) nanocrystals are elaborately synthesized and in situ loaded on cotton fibers (CFs) to form stable solar-thermal materials. The so-assembled composite PB@CF shows great light absorption, photothermal conversion and solvent self-pumping capacity, which was successfully used for photothermal purification of a library of organic solvents with the dielectric constant from 2.38 to 37.78 and a high rejection up to 99.9%. The vaporization flux ranges from 29.2 L m−2 h−1 for acetone to 0.73 L m−2 h−1 for N-methylpyrrolidone under one sun illumination, negatively correlating with the evaporation enthalpy change. The interfacial solar evaporation rate is significantly improved by 4.0–11.5 times compared to the bare solvent evaporation without the photothermal material. More practically, the composite PB@CF with excellent organic solvent resistance undergoes stable solar evaporation, even after immersion in a highly polar solvent such as N,N-dimethylacetamide for 3 months. Thus, such a robust PB@CF composite offers a prospective energy economic alternative to solving the organic solvent related issue, e.g. solvent recovery, catalyst recycle, molecular separation in petrochemical and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Inhibiting thrombosis in extracorporeal dialyzer is predominantly determined by the compatible interface design. It is challenging to develop anticoagulant dialyzers for clinical heparin free dialysis. Herein, we develop an environmentally friendly approach to construct a hydrogel skin composed of poly (sodium alginate-acrylic acid) P (SA-AA) network on polysulfone (PSf) membranes via pre-seeding initiator into membrane matrix and subsequently crosslinking SA and AA in aqueous solution. Physicochemical properties of modified membranes with different SA/AA ratio were characterized by attenuated total reflectance fourier transform infrared spectra (ATR-FTIR) spectrum, proton nuclear magnetic resonance (13 C NMR), scanning electron microscopy (SEM) and atomic force microscope (AFM) and contact angle. Antifouling property was demonstrated by proteins adsorption and E. coli adhesion. Hemocompatibility was comprehensively evaluated by hemolysis ratio, anticoagulation activity (APTT and TT), complement activation, platelets activation and contact activation. Anticoagulant dialyzer was fabricated via skin implantation strategy to implement a chronic renal swine dialysis with heparin free administration. Clotting was significantly inhibited during the whole dialysis session, moreover, the dialyzer showed improved toxins clearance, including urea (~185 mL/min), creatine (~153 mL/min), inorganic phosphorous (~120 mL/min) and β 2 -microglobulin (~110 mL/min). The modified membrane bearing abundant carboxylate groups contributes to excellent hydrophilicity and Ca2+ chelation capability, which is considered to be the predominant anti-clotting mechanism via both intrinsic and extrinsic cascades. The anticoagulant PSf dialyzer demonstrates promising clinical application for heparin free dialysis. • We develop an anti-coagulant dialyzer via constructing a hydrogel skin layer. • The membrane was endowed with carboxylic groups while preserving porous structure. • Both hydrophilicity and Ca2+ chelation enhanced hemocompatibility. • The hydrophilic dialyzer exhibited an improved toxin clearance. • The dialyzer realized the heparin free dialysis for a renal failed swine. [ABSTRACT FROM AUTHOR]

Two dimensional covalent triazine frameworks (2D-CTF) with controlled pore size and stable structure are a new class of 2D building blocks for constructing separation membrane materials. In this work, we synthesize few-layer 2D-CTF-1 nanosheets with high crystallinity and excellent solvent dispersion using a micro-interface method. The as-prepared 2D-CTF-1 membrane via filtration assembly of few-layer 2D-CTF-1 nanosheets exhibits superior permeability due to its ultralow solvent-interface interaction and the abundant in-plane pores, with a water permeance of 141.5 L m−2 h−1 at 1 bar. The skeleton-pores are proved to be the main transfer channels on 2D-CTF-1 membrane, which are stable and nondeformable by external pressure. Size screening based on the cut-off of skeleton-pore (1.39 nm) is also demonstrated, which enables 2D-CTF-1 membrane a huge application potential in precise molecule/ion sieving. Besides, a stable layered structure in aqueous environment renders 2D-CTF-1 membrane with outstanding separation performance in the long-term running, continuously keeping high permeability and selectively. Thus, this work shows a promising application of 2D-CTF-1 as building blocks for 2D membrane construction in the separation field. 2D-CTF-1 membrane with highly ordered skeleton nanopores (intrasheet pathways) as the main transfer channels exhibits robust and precise molecule/ion separation performance. Image 1 • Covalent triazine frameworks membranes were fabricated for precise separation. • The abundant skeleton-pores dominated the mass transfer of 2D-CTF-1 membrane. • Precise molecule sieving was achieved via the skeleton-pores at nano-scale. • 2D-CTF-1 membrane showed stable layered structure and separation performance. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • hNFs biocatalyst was prepared by immobilizing modified laccase. • hNFs biocatalyst activity increased to 165% compared to laccase. • hNFs biocatalyst achieved 375% pH stability and 430% temperature stability. • hNFs biocatalyst catalyzed resveratrol to obtain 45% yield of dimer with no byproduct. • hNFs biocatalyst has higher catalytic yields, specificity than chemical catalyst. Abstract In order to face the increasing demand of laccase with high stability and high performance, laccase was chemically modified by acid anhydride, and copper ion (Ⅱ) was coordinated with the hetero atom of the modified laccase to obtain the nanoflower biocatalyst. The effects of different reaction time, laccase concentration and copper sulfate concentration on the formation of nanoflowers were investigated in detail. Compared to free laccase, the enzyme activity, pH stability and thermal stability of nanoflowers increased by 165%, 375% and 430%, respectively. Furthermore, the catalytic properties of our nanoflower biocatalysts were investigated by catalyzing the synthesis of viniferin. The results showed that a higher yield of 45.0% was obtained in shorter period of time than that of the free laccase (21.6%), and the product was single without other by-products. What's more, nanoflower biocatalyst exhibited excellent storage stability, repeatability and reproducibility in cycle operation. We believed that this study provided a feasible and efficient biocatalytic method for conversion of resveratrol to viniferin. These preliminary results indicated that nanoflowers would have great potential for application in biotransformation and biocatalysis. [ABSTRACT FROM AUTHOR]

Precise ions sieving at angstrom-scale is gaining tremendous attention thanks to its significant impact at the water-energy nexus. Herein, a novel polycation-modulated interfacial polymerization (IP) strategy is developed to prepare a heterogeneously charged covalent organic frameworks (COFs) membrane. Cationic poly(diallyldimethylammonium chloride) (PDDA) regulates the growth and assembly of anionic COFs nanosheets, which thus provides a negative, smooth top surface and positive, rough bottom surface, indicating the presence of heterogeneously charged angstrom-scale channels through the membrane. Experiments and simulations are conducted to understand the facilitated ions transport behavior relative to specific interactions raised by heterogeneously charged channels and angstrom-scale steric hinderance as well, rendering the membrane with robust mono-/divalent cations sieving capabilities. The selectivity (61.6) of Li + to Mg 2+ in mixed saline under the continuous cross-flow filtration mode is superior to most of the reported nanofiltration membranes. This polycation-mediated interfacial polymerization strategy offers a compelling opportunity to develop versatile heterogeneously charged COF membranes for exquisite ion sieving., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Solid polymer electrolytes (SPEs) have garnered extensive attention as potential alternatives to traditional liquid electrolytes, primarily due to their prowess in curbing lithium dendrite formation and preventing electrolyte leaks. The quest for SPEs that are both mechanically robust and exhibit superior ionic conductivity has been vigorous. However, achieving a harmonious balance between these two attributes remains a significant challenge. In this study, we introduce a novel quasi-solid electrolyte, ingeniously crafted from a poly(urethane-urea) network, enriched with lithium salts and plasticizers. This innovative composition not only boasts remarkable toughness but also ensures commendable ionic conductivity. Our post-gelation method yields gel polymer electrolytes that undergo rigorous evaluation, leading to an optimized version that stands out with its exceptional room-temperature ionic conductivity (2.94×10 -4  S cm -1 ) and outstanding toughness (11.9 MJ m -3 ). Moreover, it demonstrates a broad electrochemical window (4.73 V), remarkable stability across a 600-hour cycle test, a high capacity retention exceeding 80 % after 100 cycles at 0.2 C, and a noteworthy self-healing capability. This quasi-solid polymer electrolyte emerges as a promising contender to replace current liquid electrolyte solutions., (© 2024 Wiley-VCH GmbH.)

The aim of this study was to investigate the molecular mechanism by which miR-497-5p regulates neuronal injury after ischemic stroke through the BDNF/TrkB/Akt signaling pathway. PC12 cells were used to construct a stroke injury model by oxygen-glucose deprivation/reoxygenation (OGD/R). The expression level of miR-497-5p was measured by RT-qPCR. CCK-8 kit was used to detect cell viability. Cell apoptosis and reactive oxygen species (ROS) were detected by flow cytometry. MDA and SOD detection kits were used to detect MDA content and SOD activity. A double luciferase reporter system was used to verify the targeting relationship between miR-497-5p and BDNF. The expression of BDNF, TrkB, p-TrkB, Akt and p-Akt was detected by Western blot. We have found that miR-497-5p expression was inhibited after treatment with OGD/R. Simultaneously, cell apoptosis, MDA content and ROS were upregulated, while cell viability and SOD were significantly decreased in PC12 cells. The effects of OGD/R on PC12 cells were reversed with the downregulation of miR-497-5p. A double luciferase reporter assay demonstrated that miR-497-5p negatively targets BDNF. BDNF inhibited cell apoptosis and oxidative stress injury in PC12 cells. These findings suggest that miR-497-5p aggravates neuronal injury in experimental model of ischemic stroke by inhibiting the BDNF/TrkB/PI3K/Akt signaling pathway.

Interactions between astrocytes and microglia play an important role in the regeneration and repair of traumatic brain injury (TBI), and exosomes are involved in cell-cell interactions. A TBI model was constructed in rats. Brain extract (Ext) was isolated 1 d after TBI. Astrocyte-derived exosomes were obtained by coculturing Ext with primary astrocytes, and the morphology of exosomes was observed by electron microscopy. The isolated exosomes were cocultured with microglia to observe phenotypic changes in M1 and M2 markers. Aberrant RNA expression was detected in necrotic brain tissue and edematous brain tissue. The role of miR-148a-3p in regulating microglial phenotype was explored by knocking down or overexpressing miR-148a-3p. Finally, the effect of miR-148a-3p on TBI was studied in a rat TBI model. Astrocyte-derived exosomes stimulated by Ext promoted the transition of microglia from the M1 phenotype to the M2 phenotype. MiR-148a-3p was highly expressed in TBI. Transfecting miR-148a-3p promoted the transition of microglia from the M1 phenotype to the M2 phenotype and inhibited the lipopolysaccharide-induced inflammatory response in pre-microglia. In a rat TBI model, miR-148a-3p significantly improved the modified neurological severity score and attenuated brain injury, which promoted the transition of microglia from the M1 phenotype to the M2 phenotype. MiR-148a-3p alleviated TBI by inhibiting the nuclear factor κB pathway. Astrocyte-derived exosomal miR-148a-3p regulates the microglial phenotype, inhibits neuroinflammation, and restores neurological function in TBI. These results provide new potential targets for the treatment of TBI., (Copyright © 2024 Qian et al.)