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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]