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Infant botulism is caused by ingesting Clostridium botulinum spores and characterized by symmetric descending paralysis, which can progress to respiratory failure in severe cases (1). Specific therapies include intravenous administration [...]

Accurately predicting the departure aircraft slip out time can effectively improve the airport surface operation efficiency and reduce the operation cost. A prediction model of departure and departure time based on BP neural network is established. The key factors influencing the actual slip out time are analyzed,and the correlation is tested. The model is verified by two weeks' actual operation data of an airport in central and southern China,and the root mean square error(RMSE),mean absolute error(MAE)and MAE percentage are analyzed. The results show that there is a strong correlation between the number of aircraft launched in the same period,the number of aircraft taking off in the same period,the number of aircraft in the same period,the average taxiing time within one hour and the taxiing time of departing aircraft. The taxiing distance,the number of turns and the delay time are related to the taxiing time,but not significant. The time period at which the aircraft takes off is not related to the slip out time. The average slip out time within 1 hour plays an important role in improving the prediction accuracy of the model. The introduction of relevant but insignificant influencing factors plays a certain role in improving the accuracy of prediction results. After the introduction of irrelevant factors,the prediction accuracy of the model will decrease significantly.

This paper aims to address the issue of environmental pollution resulting from marine oil spills by evaluating the oil adsorption performance of commonly used fence materials. Conventional oil adsorption materials exhibit limited rates and capacities for oil adsorption. Existing methods have proven insufficient in meeting the requirements for efficient and rapid oil–water separation. A new oil-absorbing barrier was developed by utilizing high oil adsorption resin as the primary material and hydroxypropyl methyl cellulose (HPMC) as the binder, leveraging the exceptional oil adsorption and hydrophobic properties of P(BMA-SMA-St)/MIL-101(Fe) resin. The oil-absorbing fence was characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The oil adsorption rates of carbon tetrachloride, toluene, diesel and gasoline by the oil adsorption fence with 25 g/L resin content were 101.26 g/m2, 68.12 g/m2, 35.19 g/m2, and 46.69 g/m2, respectively. After 120 h of UV irradiation, the coating's oil absorption capacity remained nearly unchanged, and it demonstrated outstanding mechanical, chemical, and wear resistance. As a result, the oil adsorption fence possesses the capability to rapidly absorb oil from the water's surface during the process of containing oil pollution, leading to positive social and economic impacts. [ABSTRACT FROM AUTHOR]

Melamine polyphosphate (MP), a halogen-free flame retardant was utilized to prepare flame retardant enhanced montmorillonite (MP-MMT), which was introduced into polymethyl methacrylate (PMMA) by emulsion polymerization to improve its heat resistance and flame retardancy. The decorated PMMA were characterized by SEM, FTIR, XRD, and XPS, indicating that MP-MMT/PMMA composites were successfully prepared. The resulting composites exhibited excellent heat resistance, the temperature at maximum weight loss rate was increased from 360 °C to 377 °C, and the char residue at 500 °C was increased to 1.93%. In addition, the LOI value of PMMA composite system was increased from 17.2% to 22.4%, and MP-MMT/PMMA-3 achieved UL-94 V-1 rating. Compared with pure PMMA, the total heat release and peak heat release rate of MP-MMT/PMMA were reduced by 23.0% and 32.4%, respectively. The total smoke release of the optimal flame-retardant PMMA resin decreased by 22.1%, the CO production increased slightly, and the CO2 production decreased significantly. This indicates that the incorporation of MP-MMT has a good effect on flame retardancy. Finally, the flame retardant mechanism of MP-MMT to inhibit PMMA combustion was analyzed. The intercalation modification of MMT is potentially valuable for flame retardant studies of PMMA. [ABSTRACT FROM AUTHOR]

High fire hazard, including heat release and toxic volatile production, has been the bottleneck in expanding the application of polystyrene (PS). Here, a heteroatom doping strategy is adopted to strengthen the flame-retardant effect of graphitic carbon nitride (g-C3N4) on PS. It is observed that the doped g-C3N4 fillers (PCN-1, PCN-2, PCN-3, BCN-1, BCN-2, BCN-3, PBCN-1, PBCN-2, and PBCN-3) show nanosheet-like morphologies, while common g-C3N4 presents bulky morphology. Also, the doped g-C3N4 fillers show higher thermal stability than common g-C3N4. Consequently, the doped g-C3N4 fillers show a better dispersion state in the PS matrix, benefiting the generation of an efficient barrier network. Cone results reveal that using the doped g-C3N4 fillers endows the polymer with a lower peak heat release rate, a peak smoke production rate, and a peak CO yield (PCOY). Typically, adding CN results in corresponding reductions of 7.2, 3.74, and 12.4%, respectively. By contrast, incorporating PCN-2 leads to decreases of 39.9, 23.0, and 53.2%, respectively. Thermogravimetric analysis/infrared spectrometry analysis indicates that the use of these additives contributes to the inhibition of the release of decomposed volatiles. Thus, it is firmly believed that utilizing heteroatom-doped g-C3N4 impairs the fire hazard of the polymer. [ABSTRACT FROM AUTHOR]

In order to solve the problem of demulsification of oil-water emulsion, a new type of highly efficient and recyclable magnetic fluorine-containing polyether composite demulsifier (Fe3O4@Ti-F) was synthesized. Fe3O4@Ti-F was prepared by one-pot method to combine magnetic nanomaterial TiO2 with Fe3O4 and graft fluorinated polyether. The successful synthesis of Fe3O4@Ti-F was confirmed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and X-ray diffraction (XPS). The demulsification performance of Fe3O4@Ti-F was evaluated by using the self-made crude oil emulsion as the experimental object. The demulsification mechanism of the demulsifier and the influence of external factors such as temperature and pH on the demulsification performance of the demulsifier were discussed, and the amount of TiO2 in the preparation process was determined. The results show that the demulsification efficiency of 50:50 (v/v %) W/O emulsion can reach 90.83% when the dosage of Fe3O4@Ti-F is 600 mg/L, the temperature is 65 °C and the time is 30 min. In the neutral acid environment, the demulsification rate of the demulsifier is above 80%. In addition, Fe3O4@Ti-F has been proved to have good magnetic effect. Under the action of external magnetic field, it can be recovered and recycled from the two-phase system for 4 times, and its demulsification efficiency is still above 60%. Fe3O4@Ti-F will have broad application prospects in the field of oil-water separation in an energy-saving way. [ABSTRACT FROM AUTHOR]

Oil in water (O/W) and water in oil (W/O) crude oil emulsions have caused many production safety hazards and environmental problems, which have attracted widespread attention. In this article, an amphiphilic nano demulsifier ZIF-8@CNTs was prepared by solvothermal method based on the metal-organic frameworks (MOFs) and carbon nanotubes (CNTs). Scanning electron microscopy (SEM) and infrared spectroscopy (FT-IR) showed that ZIF-8@CNTs were grape dendritic, and ZIF-8 was successfully combined with OX-CNTs. Thermogravimetric analysis (TGA) showed that ZIF-8@CNTs had good thermal stability. The demulsification test showed that the demulsification rate could reach 99.4% when ZC-1 was added at 500 mg/L for 30 min at room temperature. The demulsification mechanism was studied by interfacial tension and interfacial activity experiments. [ABSTRACT FROM AUTHOR]

In this study, a new type of highly efficient and recyclable magnetic-fluorine-containing polyether composite demulsifier (Fe3O4@G-F) was synthesized by the solvothermal method to solve the demulsification problem of oil–water emulsion. Fe3O4@G-F was successfully prepared by grafting fluorinated polyether onto Fe3O4 and graphene-oxide composites. Fe3O4@G-F was characterized using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Taking the self-made crude-oil emulsion as the experimental object, the demulsification mechanism of the demulsifier and the influence of external factors, such as the temperature and pH value, on the demulsification performance of the demulsifier are discussed. The results show that the demulsification efficiency of the Fe3O4@G-F emulsion can reach 91.38% within 30 min at a demulsifier dosage of 750 mg/L, pH of 6, and a demulsification temperature of 60 °C. In neutral and acidic environments, the demulsification rate of the demulsifier is more than 90%. In addition, Fe3O4@G-F has been proven to have good magnetic effects. Under the action of an external magnetic field, Fe3O4@G-F can be recycled and reused in a two-phase system four times, and the demulsification efficiency is higher than 70%. This magnetic nanoparticle demulsifier has broad application prospects for various industrial and environmental processes in an energy-saving manner. [ABSTRACT FROM AUTHOR]