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During the forming of aramid paper honeycomb sandwich component of aircraft composites in the autoclave, the structure bears thermo-mechanical coupling case, and it may exist the phenomenon of the honeycomb crack during the forming. The tensile, compressive, shear and thermal properties of aramid paper honeycomb core are obtained by testing. Meanwhile, the numerical simulation of thermo-mechanical sequential coupling of the whole honeycomb sandwich component and the local core area are carried out by combining the finite element analysis method and the inversion method. The results show that the thermal stress during the forming process will not cause the adhesive layer between honeycomb cells to crack, but gas pressure will. The difference value of pressure difference between honeycomb cells required for adhesive layer′s slight destruction and complete destruction is positively related to the initial normal fracture stress of adhesive layer. The pressure difference required for the adhesive layer′s complete destruction is decreased with the increase of the number of loaded cells.

In order to solve the adverse effects of sulfur oxides (SOx) released during the combustion process on the environment, health and economy, oxidative deep desulfurization of diesel has become a hotspot all over the world. In this paper, HY@TiO2-x composite catalysts with different TiO2 contents were synthesised by liquid-phase deposition using HY zeolite as the parent material. The catalysts were characterized by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Ultraviolet–Visible Diffuse Reflectance (UV–vis), Raman Spectroscopy, Scanning Electron Microscopy (SEM), N2-physisorption, X-ray Photoelectron Spectroscopy (XPS). The characterization results of XRD, FT-IR, UV–vis and Raman showed that TiO2 was successfully loaded on HY zeolite. The catalysts were applied to the oxidative desulfurization (ODS) and adsorption desulfurization of benzothiophene (BT) and dibenzothiophene (DBT). Under the selected reaction condition: T = 70℃, n(H2O2)/n(Sulfur) = 6, moil: mcatalyst = 35: 1. The results show that the HY@TiO2-1.5 catalyst has the best oxidation activity, and the conversion rates of BT and DBT were 85.0% and 99.7%, respectively. Meanwhile, the adsorption of BT and DBT were 5.06 and 10.93 mg-S/g-Cat. respectively. HY@TiO2-1.5 catalyst is simple to prepare, with a high activity of bulky organic sulfides adsorption-oxidative desulfurization and has a potential application in oil refining. The reasons for the improvement of organic sulfide adsorption and oxidative desulfurization activity on HY @ TiO2-1.5 catalyst are discussed. [ABSTRACT FROM AUTHOR]

The study of catalysts supported by polyoxometalates (POMs) with green oxidative desulfurization activity is an important research topic in oil refining. In this paper, a nano-sized H-β zeolite support was modified by tetraethyl orthosilicate (TEOS) and tetrabutyl titanate (TBOT) to form a microporous–mesoporous structure. On this basis, the modified H-β zeolite was used as a support to load POMs with different structures. The characterization results of Fourier transform infrared (FT-IR) spectroscopy, X-ray powder diffraction (XRD), ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy, scanning electron microscopy (SEM), N2 adsorption–desorption, X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy showed that POMs had been successfully loaded onto the support, and the skeleton structures of POMs and zeolites were maintained. The introduction of POMs significantly improved the ODS performance of bulky organic sulfides, especially benzothiophene (BT). The order of catalytic oxidative desulfurization activity of POMs with different structures was: Keggin > Sandwich ≈ Anderson > monovacant Dawson > Dawson > MoO3. Under the optimum reaction conditions: T = 50 °C, t = 1 h, moil : mcatalyst = 35 : 1, and n(O) : n(S) = 13 : 1, the oxidation conversion of BT and dibenzothiophene over the catalyst supported by phosphotungstic acid (HPW) reached 99.9%. The role of titanium active species, peroxide polyoxometalate, and titanium–silicon composite oxides in improving the oxidative removal of organic sulfides was discussed. [ABSTRACT FROM AUTHOR]

Although curcumin possesses anti-atherogenic and anti-inflammatory properties, its application is limited because of its low aqueous solubility and poor oral bioavailability. Recently, our group synthesized a novel linear-dendrimer methoxy-poly (ethylene glycol)-b-poly(ε-caprolactone) copolymer nanoparticle loading curcumin (Cur-NPs) which could improve solubility and release property of curcumin. In the present study, we further evaluated its anti-atherosclerotic effect in apolipoprotein E−/− mice. Our results demonstrated that the Cur-NPs significantly decreased atherosclerotic lesion areas and were more effective in stabilizing vulnerable plaques compared with free curcumin. The anti-atherosclerotic mechanisms of Cur-NPs include decreasing the number of introplaque microvessels, inhibiting the matrix metalloproteinase 2 and 9 activity, reducing the inflammatory response and regulating lipoprotein cholesterol metabolism more effectively compared with free curcumin. Furthermore, Cur-NPs could increase the amount of curcumin in the thoracic aorta and no significant toxicity was observed in the blood biochemical parameters in Cur-NPs-treated groups. Overall, our findings suggested that Cur-NPs could be a stabilized aqueous formulation for application with improved curcumin activity, which could be a potential treatment strategy for arteriosclerosis in the future. [ABSTRACT FROM AUTHOR]