Molecular dynamics simulations were used to analyze the internal mechanism for the observed improvement in performance of nano-modified meta-aramid insulation paper from a microscopic point of view. The results showed that the k-polyphenylsilsesquioxane(PPSQ) modified meta-aramid insulation paper was superior to b-PPSQ modified meta-aramid insulation paper in terms of its thermal stability and mechanical and electrical properties. The analysis of microscopic parameters showed that the stiffness of k-PPSQ was less than that of b-PPSQ, and the hydroxyl groups on the open-loop system were more likely to enter the dispersed system, resulting in higher bonding strength, meta-aramid fiber chains between k-PPSQ molecules, and the formation of hydrogen bonds. Additionally, the nano-enhancement effects of k-PPSQ and b-PPSQ resulted in various improvements, including a reduction in pores between molecules in the blend model, an increase in the contact area, the formation of interfacial polarization, and a reduction in defects at the interface.

In this work, the adsorption of SF6 decomposition products (SO2, SOF2, and SO2F2) on Ru–MoTe2 monolayer is investigated based on density‐functional theory (DFT) calculations. The doping structure, band structure, adsorption structure, adsorption energy, charge transfer, density of states (DOS), and molecular orbital are analyzed to better analyze the interaction mechanism between gas molecules and Ru–MoTe2 system. In the results, it is shown that the conductivity of MoTe2 monolayer can be greatly increased by doping Ru atom. Pristine MoTe2 shows a weak adsorption capacity for SO2, SOF2, and SO2F2 gases, which belongs to physical adsorption. When Ru atom is doped on MoTe2, the adsorption capacity of the doping system for these three gases is obviously improved. The adsorption capacity of Ru–MoTe2 monolayer to the gases is ranked as SO2F2 > SOF2 > SO2. Moreover, the strong interaction between gas molecules and Ru–MoTe2 surfaces leads to the rise of the conductivity of all adsorption systems to varying degrees, and the degree of the rise of conductivity influenced by gas molecules is ranked as SO2F2 > SO2 > SOF2. Herein, a theoretical basis for the preparation of gas sensors or adsorbers based on Ru–MoTe2 is provided for detecting and absorbing SF6 decomposition products.

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The coaxial electrospun fibers with large specific surface area, high porosity and core-shell structure have been great applied in biomedical field, especially as drug delivery carriers. In this paper, PLGA(polylactic acid/glycolic acid copolymer) was used as the core and the mixture of PLGA and gelatin was used as the shell. PLGA/gelatin fiber was prepared by coaxial electrospinning technology. The effects of different parameters on the surface morphology and the diameter of fibers were investigated.

The interaction mechanism between CO, CO 2 , and NO gas molecules and Pt n -SnS 2 (n = 1−3) and Pt n -MoTe 2 (n = 1− 3) is analyzed based on density functional theory calculations. For Pt 2 -SnS 2 , the structure of Pt 2 -SnS 2 is deformed during CO 2 adsorption. For Pt 3 -SnS 2 , its structure is also significantly deformed when the gas is adsorbed. Pt 2 -SnS 2 is not suitable for the detection and adsorption of CO 2 gas, while Pt 3 -SnS 2 is not suitable for the detection and adsorption of these three gases. According to the density of states and molecular orbital analysis, the conductivity of the adsorption system of Pt-SnS 2 remains almost unchanged after the adsorption of CO, so Pt-SnS 2 is not suitable for the detection of CO gases. The adsorption of gases on intrinsic MoTe 2 is a weakly interacting physical adsorption. Doping with one to three Pt atoms all resulted in different degrees of enhancement of the adsorption capacity of the substrates for these three target gases. However, for Pt 2 -MoTe 2 and Pt 3 -MoTe 2 , the structure of these two materials undergoes significant deformation upon NO adsorption. In addition, the interaction between Pt 3 -MoTe 2 and CO 2 is weak, and the conductivity of this system is almost unaffected by CO 2 adsorption. In addition, all other constructions are suitable for the detection of the corresponding gases. This paper provides a theoretical basis for the development of gas sensors for the detection of automotive and industrial emission gases.