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The large temperature differences between day and night in winter at plateau areas can lead to the reduction of skid resistance of roads. However, most of the traditional salt storage and deicing fillers are chlorides, and their long-term usage will cause damage to the ecological environment. In order to achieve green deicing of asphalt pavement, this paper developed efficient and environmentally friendly salt storage fibers for the anti-icing of asphalt pavement, and the optimal components of salt storage fibers were determined. On this basis, the morphology and rust resistance of salt storage fibers were characterized, and the ice suppression and deicing performances were also determined. The experimental results show that the optimal component ratio of anti-icing reagent for sodium acetate, potassium acetate and sodium formate follows 7∶2∶1 and the optimal component ratio of organic salt and fiber is 3∶1 , which can achieve a better ice-melting effect and sustainable economy. According to the scanning electron microscope (SEM) images, the salts in the salt storage fiber are fully absorbed, which has a certain slow-release performance due to the resin package. In addition, the effective anti-icing components of the salt storage fiber are less corrosive to the metal materials, and the asphalt mixtures doped with salt storage fibers can melt ice at the rate of (1,022 g/ h·m2) under relatively low temperatures. This can effectively weaken the freeze-bond strengths and ice–road interface adhesion. [ABSTRACT FROM AUTHOR]

At present, the prediction of the icing occurrence for asphalt pavement will take a lot of time, and data are relatively discrete. In this study, the heat transfer equation of phase transition was deduced based on theory of heat transfer and ice–water phase transition, and icing prediction model of pavement was also established through finite element software. The results show that the icing time and rutting plate temperature of indoor experiment are close to simulated results, which verifies effectiveness of prediction model. On this basis, when other factors remain unchanged, the lower ambient temperature and higher the wind speed will accelerate speed of road icing, but the degree of speeding up speed of road icing will reduce. The reduction of depth of accumulated water can also accelerate speed of road icing, but the degree of speeding up speed of road icing first increases and then decreases. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the nonlinear rheological behavior of two types of modified asphalt binders, namely reactive elastomeric terpolymer-modified asphalt binder (REA) and styrene-butadiene-styrene–modified asphalt binder (SBA), under large strains using large-amplitude oscillatory shear (LAOS) testing. To determine the test strain levels, we conducted strain sweeps at different temperatures and shear frequencies before subjecting the asphalt binders to the LAOS test. Our findings show that the nonlinear critical strain of asphalt binders has a temperature and frequency dependence, with smaller values at lower temperatures and higher frequencies, indicating stronger nonlinear rheological properties. We used Fourier-transform rheology to analyze the relative intensity of higher harmonics of asphalt binders (In/I1 , 3≤n≤9) and found that the nonlinear parameter I3/I1 increased with shear frequency and strain amplitude, and that the In/I1 of REA was much larger than that of SBA. To evaluate the performance of the modified asphalt binders, we used the zero-strain nonlinear parameter Q0 and found that REA had a higher Q0 value than SBA at the same frequency. Furthermore, based on the Lissajous curves at 25°C and 10 rad/s , we observed that the aberration degree of the curves increased with increasing strain amplitude. The Lissajous curves of both base asphalt binder (BA) and SBA failed to form a closed ellipse due to sample damage at larger strain levels, which means that BA and SBA are less resistant to large deformations, whereas REA maintained a higher load-bearing capacity. We also observed that both modified asphalt binders exhibited continuous shear-thinning properties. At higher strains, the intermolecular forces in SBA were overcome by shear deformation, whereas the chemical bonds formed between oxygen-containing functional groups and carboxylic acid groups in REA were gradually broken by stretching. LAOS test results demonstrated that REA exhibited higher deformation resistance potential at large strain levels compared with SBA. [ABSTRACT FROM AUTHOR]

Improving hepatic glucose and lipid metabolisms is an important strategy to treat type 2 diabetes mellitus complicated with non-alcoholic fatty liver disease (T2DM-NAFLD). Silybin (SLB) has the potential hepatoprotection, while its oral bioavailability is poor. This study aims to investigate the functional role and mechanism of liposomal SLB in modulating glucose/lipid metabolism in T2DM-NAFLD. SLB was prepared by thin film dispersion method and characterized using dynamic light scattering, scanning electron microscope, high performance liquid chromatography and zeta potential analyzer. A rat model of T2DM-NAFLD was used to determine the role of liposomal SLB in regulating glycolipid metabolism and hepatic damage. Rat primary hepatocytes were used to demonstrate the hepatoprotection mechanism of liposomal SLB. The encapsulation efficiency was more than 80%, which showed the average particle size of 119.76 nm. Also, the average Zeta potential was -4.76 mV. These liposomes were spherical. In rats with T2DM-NAFLD, liposomal SLB alleviated insulin resistance and lipid metabolism, thereby improving hepatic lipid accumulation, inflammation and fibrosis. Besides, liposomal SLB elevated AMPK phosphorylation, and decreased collagen I/III, α-smooth muscle actin (α-SMA), transforming growth factor-β1 (TGF-β1) and the phosphorylation of Smad2/3. In hepatocyte model, compound C partially reversed the effects of liposomal SLB on cell viability, glycolipid metabolism and AMPK/TGF-β1/Smad pathway activation. Liposomal SLB ameliorates hepatic glucose and lipid metabolisms in T2DM-NAFLD via activating AMPK/TGF-β1/Smad pathway, providing an efficient strategy for treating T2DM-NAFLD.