RESUMO
Electromagnetic interference (EMI) shielding and infrared stealth technologies are essential for military and civilian applications. However, it remains a significant challenge to integrate various functions efficiently into a material efficiently. Herein, a minimalist strategy to fabricate multifunctional phase change organohydrogels (PCOHs) was proposed, which were fabricated from polyacrylamide (PAM) organohydrogels, MXene/PEDOT:PSS hybrid fillers, and sodium sulfate decahydrate (Na2SO4·10H2O, SSD) via one-step photoinitiation strategies. PCOHs with a high enthalpy value (130.7 J/g) and encapsulation rate (98%) could adjust the temperature by triggering a phase change of SSD, which can hide infrared radiation to achieve medium-low temperature infrared stealth. In addition, the PCOH-based sensor has good strain sensing ability due to the incorporation of MXene/PEDOT:PSS and can precisely monitor human movement. Remarkably, benefiting from the electron conduction of the three-dimensional conductive network and the ion conduction of the hydrogel, the EMI shielding efficiency (k) of PCOHs can reach 99.99% even the filler content as low as 1.8 wt %. Additionally, EMI shielding, infrared stealth, and sensing-integrated PCOHs can be adhered to arbitrary targets due to their excellent flexibility and adaptability. This work offers a promising pathway for fabricating multifunctional phase change materials, which show great application prospects in military and civilian fields.
RESUMO
NOx and SO2 formation in the sintering process and the influence of coke powder content, moisture content and adding additives on NO emissions were investigated by the sintering pot experimental method. The results showed that the combustion zone moved downward along the sintering pot after the sintering started. The NOx concentrations of all monitoring points below the combustion zone were basically the same. SO2 generated in the combustion zone was adsorbed and accumulated in the sintering materials below the zone. Then, SO2 was released by pyrolysis, and finally discharged from the outlet of sintering pot. So the significant SO2 couldn't be detected before the burning through point, and the relationship between the SO2 concentration and the sintering time displayed an inverted "V" curve. NOx produced from the sintering process was mainly thermal-NOx, and most of it was NO, the NO2 concentration was very low. Reducing the coke powder and moisture contents, or adding sintering additives could effectively reduce NOx emissions.