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Thermoresponsive microgels are a kind of soft and wet material exhibiting various potential applications such as smart windows. As a concept of proof, poly(N‐isopropylacrylamide) based thermoresponsive microgel shows excellent promise in thermochoromic smart windows. While relatively expensive monomers lead to an unacceptable cost when they are used as building materials. In this work, efforts are made to exploration of an alternative for poly(N‐isopropylacrylamide) reducing the cost of thermoresponsive microgels. For this purpose, industrial chemicals acrylamide (AM) and diacetone acrylamide (DAAM) are employed to synthesize microgels through free radical precipitation polymerization. Although both homopolymers of acrylamide and diacetone acrylamide are not thermoresponsive. Their copolymers exhibit typical lower solution temperature solution (LCST) behaviors, which confirm the feasibility of the envisaged. Further, the influence of synthetic conditions including monomer ratio, concentration of surfactant, and polymerization temperature, on the size and responsive temperature of microgels is investigated. Ultimately, cost‐effective thermoresponsive microgels are prepared with adjustable diameters from 1.6 to 4.5 µm and responsive temperature from 19.3 to ≈70.0 °C. [ABSTRACT FROM AUTHOR]

C5F10O-insulated environmental-friendly power equipment has great potential to be used in the near future to reduce greenhouse effect. During maintenance, C5F10O should be supplemented or replaced, and the released gas is promisingly to be removed by advanced oxidation processes, but chemical kinetics of C5F10O with the most reactive and dominant species ·OH radical in air plasma is still not clear. Therefore, this paper studied the degradation pathways and rate constants of C5F10O + ·OH in both gaseous and aqueous phases with M06-2X/6-31G* method and transition state theory. A continuum solvation model was also employed to study the influence of solvent on chemical kinetics of C5F10O + ·OH. The results show that most reactions (except for R7 and R8) in both phases have a similar transition state vibration mode leading to same products but rate constants are different. The rate constants of reactions R5 and S5 are highest in corresponding states, respectively, playing a dominant role in the degradation of C5F10O + ·OH, but the rate constant of reaction S5 is much lower indicating that AOP treatment for C5F10O in gas phase is more effective. This work lays a theoretical basis for plasma modeling and experimental investigation for C5F10O degradation by advanced oxidation process. [ABSTRACT FROM AUTHOR]

Due to the growing problem of global warming, C5F10O is promising to replace SF6 as an insulation medium in power equipment because of its low global warming potential and excellent insulation performance and thus has a wide application prospect in the electrical engineering field. Local over-thermal fault is one of the most severe faults in power equipment and has a close relationship with the characteristic decomposition components (CDCs). This paper is devoted to proposing an evaluation method for local over-thermal fault by analyzing CDCs. The discrete wavelet transformation method was adopted to recognize CDC (CF2, CF2CF2, COCF2, and CFCF3) from their variation curves, and the fault feature vector was extracted based on the analysis of frequency band energy. The back propaganda neural network optimized by the genetic algorithm was employed to evaluate the severity of local over-thermal fault with a high accuracy. This work can lay a theoretical basis for local over-thermal fault evaluation based on CDCs in environmentally friendly power equipment. [ABSTRACT FROM AUTHOR]