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Passive daytime radiative cooling has emerged as a promising green technology for the thermal management of buildings, vehicles, textiles, and electronics. Typically, both high solar reflectance and high thermal emissivity are prerequisites to achieve sufficient daytime cooling. However, colored radiative cooling materials are facing the dilemma of introducing visible light absorption, leading to challenges in balancing cooling and aesthetic demands. Here, three colored bilayer radiative cooling coatings, each comprised of a white base layer and a colored top layer with fluorescence enhancement are fabricated. Three phosphors (Sr2Si5N8:Eu2+, Y3Al5O12:Ce3+, and (Ba,Sr)SiO4:Eu2+) are employed with respective photoluminescence quantum yields (PLQYs) of 81%, 95.8%, and 91.0% as the colored pigment in the top layer. To mitigate the contradiction between coloration and solar reflectance, SiO2 microspheres are introduced into the top layer and utilize their Mie‐resonance‐based multiple scattering to increase the photoluminescent (PL) properties of the phosphors, which jointly boosts the effective solar reflectance (ESR) of the top layer. As a result, the three bilayer coatings exhibit soft colors while achieving subambient cooling with temperature drops of up to 1.5 °C. This fluorescence‐enhancement strategy may pave the way for preparing highly efficient radiative cooling coatings with tunable colors. [ABSTRACT FROM AUTHOR]

Existing studies have proved that interfaces between the prefabricated layer and the cast‐in‐place layer significantly affect the static performance of prefabricated concrete structures using the wet connection method, but little has been known about the fatigue performance, especially at high load levels. This study investigated the fatigue behavior of prefabricated composite concrete beams under negative bending moment induced by the high‐stress level cyclic load. Fifteen composite T‐beams with three different designed sections were tested. The failure mode, cracking and deflection behavior, steel strain development, and the new‐old concrete interfacial deformation were recorded and analyzed. It was found that the stress redistribution occurred with the debonding cracks generated at the new‐old concrete interface, causing the degradation of the static and fatigue performance. Setting interfacial shear keys could prevent such debonding failure at static and low cyclic loading levels. Meanwhile, the corresponding mechanisms were verified through cross‐sectional analysis. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for numerically simulating the chloride diffusivity in mortar subjected to corrosion‐induced cracking with the aid of X‐ray microcomputed tomography (X‐ray µCT). In the research, the mortar sample with embedded steel rod was subjected to accelerated corrosion and then scanned by X‐ray µCT at consecutive corrosion periods of 0, 1,000, and 2,000 minutes. Upon the scanned CT images, a meso‐scale model consisting of multiple material phases with their intrinsic structures was built up and implemented into a finite element method for diffusion simulation. In the numerical simulation, the effects of multiple phases (void, crack, aggregate, rust, and interfacial transition zone between cement and aggregate) on the chloride diffusion of mortar are studied. Since the X‐ray µCT facilitates accurate local material information in time‐dependent and in situ manner, the diffusivity of mortar under different corrosion time and its spatial distribution characteristics (e.g., at different locations from the mortar surface) can be evaluated. [ABSTRACT FROM AUTHOR]

To further explore the underlying antidepressant mechanism of ginseng total saponins (GTS), this study observed the effects on hippocampal astrocyte structural plasticity and hippocampal volume in the corticosterone-induced mouse depression model. Corticosterone (20 mg/kg/day) was administered subcutaneously for 5 weeks, and GTS (12.5, 25, and 50 mg/kg/day; namely GTSL, GTSM, and GTSH) or fluoxetine (10 mg/kg/day) were given intragastrically during the last 3 weeks. On day 33 and day 34, depression-like behavior was observed via a forced swimming test and a tail suspension test, respectively. At 6 h after the last dose of corticosterone (day 35), all mice were sacrificed followed by serum corticosterone assays, stereological analysis of hippocampal glial fibrillary acidic protein-positive (GFAP+ ) astroctyes and hippocampal volume, and hippocampal glycogen tests. Results showed that all doses of GTS ameliorated depression-like behavior and the decrease in hippocampal glycogen without normalizing hypercortisolism. Moreover, GTSH and GTSM reversed the corticosterone-induced reduction in the total number of hippocampal GFAP+ astrocytes and hippocampal volume. Additionally, GTSH alleviated the diminished protrusion length and somal volume of GFAP+ astrocytes induced by corticosterone. These findings imply that the effects of GTS on corticosterone-induced depression-like behavior may be mediated partly through the protection to hippocampal astrocyte structural plasticity. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Allowing for the tension stiffening effects resulting from the bond between steel reinforcement and surrounding concrete leads to effective deformation analysis of reinforced concrete (RC) members when using a nonlinear finite element analysis modeled on the smeared crack concept. Nowadays, externally bonded fiber reinforced polymer (FRP) composites are widely used for strengthening existing RC structures. However, it remains unclear to what extent the tension stiffening of postcracking concrete is quantitatively influenced by the addition of FRP composites, as a result of the bond between the FRP and the concrete substrate. This article presents a discrete model, which is based on rigid body spring networks (RBSN), for investigating the tension stiffening behavior of concrete in FRP-strengthened RC tensile members. A two-parameter fracture energy-based model was deployed to represent the bond-slip behavior of the FRP-to-concrete interface. The reliability of the RBSN model was verified through comparisons with previous test results. Further parametric analysis indicates that the tension stiffening of concrete is hardly influenced by the addition of FRP composites before the yield of steel reinforcement has occurred although concrete crack patterns and crack widths may be influenced by the bond-slip behavior of the FRP-to-concrete interface. [ABSTRACT FROM AUTHOR]