The wide application of flexible polyurethane foam (FPUF) poses a giant challenge to human society in terms of fire prevention and environmental pollution. To solve this problem, the lignocellulose-based P-N flame retardant (LFPN) has been developed using mechanochemical methods. It was found that FPUF treated using LFPN exhibited good flame retardancy, but suffered from high smoke generation and toxicity.
View Article and Find Full Text PDFDue to frequent petrochemical spills, environmental pollution and the threat of secondary marine fires have arisen, necessitating an urgent need for petrochemical spill treatment strategies with high-performance oil-water separation capabilities. To address the challenges of poor durability, instability in hydrophobic conditions, and difficulty in absorbing high-viscosity crude oil associated with hydrophobic absorbent materials, the authors of this study took inspiration from the unique micro and nanostructures of springtails' water-repellent skin. We engineered a superhydrophobic melamine sponge using interfacial assembly techniques designated as Si@PBA@PDA@MS.
View Article and Find Full Text PDFSimultaneously enhancing the fire safety and mechanical properties of epoxy resin (EP) remains a persistent challenge. Herein, a high-efficient phosphaphenanthrene-based flame retardant (FNP) is synthesized using 3,5-diamino-1,2,4-triazole, 4-formylbenzoic acid, and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide. Due to the presence of active amine groups, FNP is employed as a co-curing agent for fabricating EP composites with outstanding fire safety and mechanical properties.
View Article and Find Full Text PDFThe aircraft electro-thermal anti-icing system that can guarantee flight safety may be affected by periodic heating and cyclic aerodynamic force during long-term flight missions, which seems to be a potential threat to ice protection. This paper aims to investigate the impacts of thermal and mechanical cycles on heating elements of the electro-thermal anti-icing system. Specimens were manufactured with CFRP (carbon fiber reinforced polymer) laminated composite, glass fiber prepreg and copper screen, in which sprayable metal film (SMF) was embedded as the heating element.
View Article and Find Full Text PDFBased on the 12-hour PM samples collected in an urban site of Beijing, sixteen PM-bound Polycyclic Aromatic Hydrocarbons (PAHs) were measured to investigate the characteristics and potential source regions of particulate PAHs in Beijing. The study period included the summer period in July-August 2014, the APEC source control period during the Asia-Pacific Economic Cooperation (APEC) meeting in the first half of November 2014, and the heating period in the second half of November 2014. Compared to PM, sum of 16 PM-bound PAHs exhibited more significant seasonal variation with the winter concentration largely exceeding the summer concentration.
View Article and Find Full Text PDFThe Atractylodes macrocephala polysaccharide (AMP) was extracted purified and modified in selenylation by Nitric acid-sodium selenite method to get nine selenizing AMPs (sAMPs), sAMP(1)-sAMP(9). In vitro test their effects on chicken peripheral lymphocyte proliferation were determined by MTT assay. The results showed that nine sAMPs and AMP at five concentrations could significantly promote lymphocyte proliferation, the actions in six sAMPs were significantly stronger than that in AMP, and in sAMP(9) was the strongest.
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