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Transportation structures such as composite pavements and railway foundations typically consist of multi-layered media designed to withstand high bearing capacity. A theoretical understanding of load transfer mechanisms in these multi-layer composites is essential, as it offers intuitive insights into parametric influences and facilitates enhanced structural performance. This paper employs an improved transfer matrix method to address the limitations of existing theoretical approaches for analyzing multi-layer composite structures. By establishing a two-dimensional composite pavement model, it investigates load transfer characteristics and validates the accuracy through finite element simulation. The proposed method offers a straightforward analytical approach for examining internal interactions between structural layers. Case studies indicate that the concrete surface layer is the main load-bearing layer for most vertical normal and shear stresses. The soil base layer reduces the overall mechanical response of the substructure, while horizontal actions increase the risk of interfacial slip and cracking. Structural optimization analysis demonstrates that increasing the thickness of the concrete surface layer, enhancing the thickness and stiffness of the soil base layer, or incorporating gradient layers can significantly mitigate these risks of interfacial slip and cracking. The findings of this study can guide the optimization design, parameter analysis, and damage prevention of multi-layer composite structures.

Understanding the spatiotemporal dynamics of coastal intertidal meta-ecosystems in response to sea-level rise (SLR) is essential for understanding the interactions between terrestrial and aquatic meta-ecosystems. However, given that annual SLR changes are typically measured in millimeters, ecosystems may take decades to exhibit noticeable shifts. As a result, the extent of lateral responses at a single point is constrained by the fragmented temporal and spatial scales. We integrated the tidal inundation gradient of a coastal meta-ecosystem—comprising a high-elevation flat (H), low-elevation flat (L), and mudflat—to quantify the potential application of inferring the spatiotemporal impact of environmental features, using China’s Yangtze Estuary, which is one of the largest and most dynamic estuaries in the world. We employed both flood ratio data and tidal elevation modeling, underscoring the utility of spatial modeling of the role of SLR. Our results show that along the tidal inundation gradient, SLR alters hydrological dynamics, leading to environmental changes such as reduced aboveground biomass, increased plant diversity, decreased total soil, carbon, and nitrogen, and a lower leaf area index (LAI). Furthermore, composite indices combining the enhanced vegetation index (EVI) and the land surface water index (LSWI) were used to characterize the rapid responses of vegetation and soil between sites to predict future ecosystem shifts in environmental properties over time due to SLR. To effectively capture both vegetation characteristics and the soil surface water content, we propose the use of the ratio and difference between the EVI and LSWI as a composite indicator (ELR), which effectively reflects vegetation responses to SLR, with high-elevation sites driven by tides and high ELRs. The EVI-LSWI difference (ELD) was also found to be effective for detecting flood dynamics and vegetation along the tidal inundation gradient. Our findings offer a heuristic scenario of the response of coastal intertidal meta-ecosystems in the Yangtze Estuary to SLR and provide valuable insights for conservation strategies in the context of climate change.

The wide-spread application of carbon fiber-reinforced polymer (CFRP) composites in industrial fields has led to high demand for developing a rapid detection method for assessing the structural performance of CFRP composites in operation based on optical fiber sensing technology. Therefore, the effectiveness and reliability of evaluating the fatigue resistance of CFRP plates based on fiber Bragg grating (FBG) monitoring information were explored. The strain response of CFRP plates at key positions under constant amplitude fatigue load was monitored by bare FBGs in series and packaged quasi-distributed FBGs in series. The structural performance and fatigue resistance characteristics of CFRP plates were evaluated by statistical analysis and fatigue life prediction theory. The validity and accuracy of the test and analysis results were demonstrated by finite element modeling analysis. Compared with the traditional methods that evaluate the structural fatigue performance based on mass destructive experiments, this method significantly improves the detection efficiency and realizes the non-destructive and rapid online evaluation of structural service performance. Research shows that the designed FBG sensors can effectively monitor the strain response of CFRP plate under fatigue load, and the correlated fatigue algorithm can provide feasible and reliable technical approaches for online detection and evaluation on the structural performance of CFRP components.

As a key storage facility, the structural safety of large oil tanks is directly related to the stable operation of the energy system. The static pressure caused by the change of liquid level is one of the main loads in the service process of storage tanks, which determines the structural deformation and damage risk. To explore the structural deformation properties under the change of liquid levels and provide a theoretical basis for the prevention and control of damage risk, this paper systematically analyzes the mechanical response of storage tanks under the pressures induced by different liquid levels based on the shell theory. Combined with the finite element software COMSOL, the radial displacement and stress-strain distribution under different liquid levels are simulated to verify the accuracy and effectiveness of the proposed theoretical model. The increase in liquid level and radius aggravates the radial deformation and makes the risk point move up, while the increase in wall thickness can effectively reduce the deformation response. Suggestions on the monitoring zone and damage risk prevention measures have also been given to instruct the safe operation of oil tanks. The research provides theoretical support for the optimization design of storage tank structures, the construction of advanced structural health monitoring system and the prevention and control of damage risk.

Designing efficient and affordable electrocatalysts for reversible oxygen electrocatalysis (oxygen reduction reaction [ORR] and oxygen evolution reaction [OER]) reactions is highly desirable for rechargeable metal–air batteries. The hybrid electrocatalysts composed of transition metal oxides and N‐doped carbonaceous materials are promising bifunctional ORR/OER electrocatalysts, whose improved electrocatalytic activities can be attributed to the synergistic effect originated from the metal–N–C active sites. Herein, NiFe2O4/N‐doped graphene (NFO/NG) composites are prepared which own enhanced OER, especially superior ORR performance for the utilization of rechargeable Zn–air batteries. Significantly, it is also verified that the interfacial Ni–(pyridinic or pyrrolic) N–C species, rather than Fe–N–C, play key role infactors for promoting ORR/OER bifunctional electrocatalysis. The optimized catalyst displays remarkably reduced overpotential for both ORR and OER with an overall potential difference as low as 0.67 V. The assembled rechargeable Zn–air battery shows a high specific capacity (513.6 mA h gzn−1) and power density (173.6 mW cm−2), as well as a long‐term cycling stability. For NiFe2O4/N‐doped graphene nanocomposites, it is verified that the interfacial Ni–(pyridinic or pyrrolic) N–C species, rather than Fe–N–C, are identified to predominantly contribute to synergistic catalysis, and substantially promoting oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) bifunctional electrocatalysis. The assembled rechargeable Zn–air battery also possesses a high specific capacity and power density, as well as a long‐term cycling stability.

A novel bipolar host tris(4-(pyrimidin-5-yl)phenyl)amine(TPMTPA) constructed by incorporating triphenylamine as the electron-donating core and pyrimidine as the electron-accepting peripheries was designed and synthesized.TPMTPA achieves excellent bipolar charge transport properties and has high enough triplet energy level to sensitize green,yellow,orange,red and deep-red phosphors.By using TPMTPA as a host,high performance green,yellow,orange,red and deep-red phosphorescent organic light-emitting devices(PhOLEDs) were demonstrated with maximum external quantum efficiencies of 20.4%,17.6%,15.1%,15.3%and 15.7%respectively.These results suggested that TPMTPA is a versatile high performance host for PhOLEDs of different emission colors.

A novel bipolar host tris（4-（pyrimidin-5-yl）phenyl）amine （TPMTPA） constructed by incorporating triphenylamine as the electron-donating core and pyrimidine as the electron-accepting peripheries was designed and synthesized. TPMTPA achieves excellent bipolar charge transport properties and has high enough triplet energy level to sensitize green, yellow, orange, red and deep-red phosphors. By using TPMTPA as a host, high performance green, yellow, orange, red and deep-red phosphorescent organic light-emitting devices （PhOLEDs） were demonstrated with maximum external quantum efficiencies of 20.4%, 17.6%, 15.1%, 15.3% and 15.7% respectively. These results suggested that TPMTPA is a versatile high performance host for PhOLEDs of different emission colors.

In virtue of Auger electron spectroscopy, the grain boundary concentrations of phosphorus in Ni-Cr-Fe superalloy are measured after solution treatment at 1 180 ℃ for 45 min. The results show that a peak of phosphorus concentration occurs at about 180 min during isothermal ageing at 500 ℃, and a maximum concentration of phosphorus appears also at about 500 ℃ for all specimens aged for 20 min at temperatures of 200, 400, 500, 700 and 800 ℃. The results are analyzed with the laws of nonequilibrium grain boundary segregation. It is found from the analysis that peaks are related to critical time for nonequilibrium grain boundary segregation of phosphorus.

In order to confirm the segregation characteristic of phosphorus in an Fe-17Cr alloy at grain boundary, the phosphorus segregation was obtained by Auger electron spectroscopy. The results show that a maximum phosphorus segregation appeared at 450 °C for all specimens aged for 30 min at 350, 400, 450, 500, and 600 °C after being solution-treated at 1000 °C for 1 h. These results were analyzed by the characteristics of segregation peak temperature of non-equilibrium segregation.

Exploring high‐safety but convenient encryption and decryption technologies to combat threats of information leakage is urgently needed but remains a great challenge. Here, a synergistically time‐ and temperature‐resolved information coding/decoding solution based on functional photonic inks is demonstrated. Encrypted messages can be stored into multiple channels with dynamic‐color patterns, and information decryption is only enabled at appointed temperature and time points. Notably, the ink can be easily processed into quick‐response codes and multipixel plates. With high transparency and responsive color variations controlled by ink compositions and ambient temperatures, advanced 3D stacking multichannel coding and Morse coding techniques can be applied for multi‐information storage, complex anticounterfeiting, and information interference. This study paves an avenue for the design and development of dynamic photonic inks and complex encryption technologies for high‐end anticounterfeiting applications. Here, a synergistically time‐/temperature‐resolved information coding/decoding solution based on a photonic anticounterfeiting ink is demonstrated. The ink can be easily processed into different patterns, which enable the storage of messages into multiple channels as well as the information decryption at appointed temperature and time points, providing inspirations for advanced information‐encryption and anticounterfeiting technologies.