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Polyphenylene oxide and the intumescent flame retardant were used in combination to achieve the fire-retardancy of polystyrene. The IFR system is mainly composed of ammonium polyphosphate, pentaerythritol and melamine. To solve the problems existed in the ternary IFR system, such as hydrophilicity and heterogeneity in particle size and mixing, IFR powders were surface modified by silane coupling agent KH-550 via wet ball milling. The results showed that the combination of PPO and IFR could effectively enhance the thermal stability and improve the flame-retardant performance of composites, with the synergistic effect between them.

The three-dimensional target position is vital to automatic driving, which can efficiently detect the geometrical shape of obstacles and achieve automatic environment recognition for both indoor and outdoor scenarios. In this paper, we propose an RFID 3D localization prototype based on the polarization phase model. To eliminate the impacts of tag angle, we leverage the polarization effect to obtain polarized phases. After that, we use polarized phase decomposition to get pure phases, i.e., the phase corresponding to the line of sight path. Hence, we can calculate the raw phases using the HMFCW algorithm. Finally, we can estimate the target’s 3D position according to unwrapped phase information. In this way, we implement a low-cost, high-precision, easy-for-deployment 3D position solution using commercial UHF RFID hardware. The experiments show that the method can obtain effective positioning results in various environments and achieve positioning accuracy with an average error of about 9 cm.

Corrosion of steel rebars in alkaline environments can be exacerbated in hot weather conditions, which has a direct impact on the durability of reinforced concrete structures. Here, the corrosion resistance of 304LN stainless steel and carbon steel rebars were studied using the electrochemical impedance spectroscopy and potentiodynamic polarization techniques in chloride contaminated concrete pore solution at various temperatures. Corrosion rate of all samples had increased with increasing exposure temperatures from 25 ᵒC to 55 ᵒC. Polarization data revealed enhanced corrosion resistance of stainless steel rebar under hot alkaline environments compared to carbon steel rebar which can be attributed to the formation of chemically stable, thin and passive oxide layer caused by chromium into the stainless steel structures. The electrochemical results indicate that 304LN stainless steels reveal a higher impedance with a higher durability, lower corrosion current density, and higher corrosion resistance than carbon steel.