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Shell materials play significant impact on corrosion resistance and mechanical properties on self-healing coating of composite with core-shell nanofiber. In this paper, three promising shell materials were investigated to optimize the performance of self-healing coating. Self-healing core-shell nanofibers with different shell materials were prepared with coaxial electrospinning. The resulting nanofibers were used to prepare self-healing corrosion resistance coating. The tensile test revealed a notable enhancement in the tensile strength of PA6 core-shell nanofiber epoxy composite coatings compared with the epoxy coating, demonstrating increase of 26.92%. Friction and wear test indicated reductions in the friction coefficients of PAN, PVDF, and PA6 core-shell nanofibers by 13.82%, 12.44%, and 26.27%, respectively. The self-healing and anti-corrosion abilities were evaluated through electrochemical impedance spectroscopy (EIS) test. All three coatings exhibited exceptional self-healing efficiencies exceeding 90%, highlighting the substantial potential of the chosen shell materials as nanocontainers for self-healing agent. Results indicate that the nanofibers with PA6 as shell material can achieve the best enhancement performance, which has a greater potential for the corrosion protection and long-lasting use of offshore wind turbine tower coatings. Highlights * Optimizing coating performance by screening coaxial nanofibers for shell materials * Shell material can improve the tensile strength of coating up to 26.92% * Friction coefficient of PA6 nanofiber coating was about 15% lower than PAN and PVDF * All three coatings exhibited exceptional self-healing efficiencies exceeding 90% KEYWORDS coating, core-shell nanofibers, mechanical properties, self-healing, shell material, 1 | INTRODUCTION Offshore wind turbine towers are easy to be corrosive under high humidity and high salt spray marine environments. (1) Application of anti-corrosion coating with self-healing ability is [...]

C21H25ClO, orthorhombic, Pna21 (no. 33), a = 14.152(2) Å, b = 22.112(3) Å, c = 6.0109(7) Å, V = 1880.9(4) Å3, Z = 4, Rgt(F) = 0.0586, wRref(F2) = 0.1227, T = 150 K.

Carbon emissions and land use intensity serve as crucial indicators of land management. This paper proposes a methodological framework to elucidate the sustainability of carbon emissions in rural areas via a coordination model, scrutinizes the correlation with land use intensity, and investigates the significance of influential factors. The study focuses on village-level units within Ningde City, and finds the pronounced spatial heterogeneity characterizing the distribution of carbon emissions across different villages: (1) Villages exhibiting high levels of carbon emissions are predominantly concentrated in the southeast region, whereas those with low carbon emission levels are primarily clustered in the northwest region. The majority of the villages serve as net carbon emission sources. (2) Spatial disparities exist in the impact of land use intensity on economic benefits from carbon sources, ecological benefits from carbon sinks, and carbon emission sustainability. (3) Significant variations exist in the influence of factors affecting land use intensity, economic benefits of carbon sources, ecological benefits of carbon sinks, and the sustainability of carbon emissions in rural areas. These findings could guide governments in implementing distinct land use control policies and provide a framework for assessing carbon emission sustainability within land management strategies. [ABSTRACT FROM AUTHOR]

As the impact of climate change intensifies, meeting the energy demand of buildings in China's cold regions is becoming increasingly challenging, particularly in terms of cooling energy consumption. The effectiveness of integrating phase change material (PCM) into building envelopes for energy saving in China's cold regions is unclear. The aim of this study is to assess the effectiveness of PCM integration in building enclosures for energy efficiency in these regions. The research monitored and recorded indoor temperature data from typical residential cases from May to September. This measured data was then used to validate the accuracy of EnergyPlus22-1 software simulation models. Subsequently, the calibrated model was utilized to conduct a comparative analysis on the effects of PCM on indoor temperatures and cooling energy consumption across these regions. The results of these comparative analyses indicated that PCM can alleviate indoor overheating to varying degrees in severe cold regions of China. Focusing on north-facing bedrooms, applying PCMs reduced the duration of overheating in non-air-conditioned buildings in severe cold regions of China by 136 h (Yichun), 340 h (Harbin), 356 h (Shenyang), and 153 h (Dalian). In terms of cooling energy consumption, the energy saved by applying PCMs ranged from 1.48 to 13.83 kWh/m2. These results emphasize that the performance of PCM varies with climate change, with the most significant energy-saving effects observed in severe cold regions. In north-facing bedrooms in Harbin, the energy-saving rate was as high as 60.30%. Based on these results, the study offers guidance and recommendations for feasible passive energy-saving strategies for buildings in severe cold and cold regions of China in the face of climate change. Additionally, it provides practical guidance for applying PCMs in different climatic zones in China. [ABSTRACT FROM AUTHOR]

In China, the post-Winter Olympics era has seen the rapid development and promotion of ice rinks with air-supported membrane structures. With the rise of large indoor spectator areas in ice rinks, thermal comfort needs in spectator areas are receiving more and more attention. The satisfaction of thermal comfort needs is crucial to people's health and well-being, so further study of the issue of thermal comfort in such spectator areas is needed. Unfortunately, models currently used to evaluate the thermal comfort of traditional building envelopes are not applicable to air-supported membrane-envelope ice rinks. Researchers need to focus on the internal thermal comfort needs of air-supported membrane envelopes for spectator areas. The aim of this research was to establish a thermal comfort model to provide exact temperature-range recommendations for spectator areas in air-supported membrane ice rinks. The indoor thermal-environment parameters of the ice rink in Harbin were measured from 2 January to 15 January 2023. To elicit data on spectators' actual thermal sensations in the ice rink, a field questionnaire was administered. By modifying the expectancy factor, an extended predicted thermal comfort model was established. The results suggested that the operative temperature required to meet spectators' thermal comfort needs in the case study ice rink ranged from 17 °C to 26 °C. The results of the study offer specific insights into the indoor thermal comfort needs of air-supported ice rinks and provide a more accurate temperature-setting reference for the healthy and energy-efficient development of such rinks. [ABSTRACT FROM AUTHOR]

Due to global warming, the overheating risk in the severe cold region of China has attracted attention, but so far, no studies have examined summer overheating in this region. This paper aims to reveal the overheating risk in recent and future climates in the severe cold region of China. An 18-storey residential building in the severe cold region of China was monitored from May to September 2021 to validate the simulation data of the indoor temperature. Weather files of the typical meteorological year (TMY) from 2007 to 2020, observations in 2021, and forecasts for the climate in different carbon emission scenarios (2030, 2060) were used to simulate the indoor temperature and assess the overheating risk. The results revealed the severity of the overheating risk; the overheating hours in the south-facing bedroom were recorded as 884 h (24.07%) with the TMY weather data and 1043 h (28.40%) in 2030 and 1719 h (46.81%) in 2060 under the RCP8.5 carbon emission scenario. Thus, the low carbon emissions policy may significantly alleviate overheating. Moreover, to cope with climate change, it is suggested that the Chinese local design standards should consider the summer overheating risk and make the necessary adjustments. [ABSTRACT FROM AUTHOR]

Metallic glasses (MGs) have excellent properties, such as high strength and low elastic modulus, can be used as reinforcement in metal matrix composites. In this paper, aluminum matrix composites reinforced with Fe80Si9B11 MG strips with different weight contents (5, 10, 15, 20 and 25%) were produced by roll-bonding at an initial temperature of 450 °C and 80% deformation. Tensile mechanical tests showed that the tensile strength of the composite sheets containing 10% MG strips showed the highest tensile strength of 166 MPa. Further studies on the sandwich structured samples were conducted using high-pressure torsion (HPT) technology with various pressures of 0.55 GPa, 1.10 GPa, 1.65 GPa, and 2.20 GPa. X-ray diffractometry (XRD), scanning electron microscopy (SEM), TriboIndenter nanomechanical testing, and transmission electron microscopy (TEM) were used to study the microstructures, mechanical properties and the bonding interface of the material. The results show that the hardness near the interface presented a transition area. High-resolution TEM observation showed that physical metallurgical bonding can be achieved between MG and aluminum alloy. A preliminary fitting of metallurgical bonding conditions was carried out according to the experimental parameters of HPT and the interface bonding condition in this study. [ABSTRACT FROM AUTHOR]

The corrosion resistance of multi-principal element alloy (MPEA) films is complex dependent on their composition. The purpose of this paper is to explain the relationship between the corrosion resistance and the Cu content of AlCuxNiTiZr MPEA films. AlCuxNiTiZr films were deposited by magnetron sputtering. Their corrosion resistance in 3.5 wt. % NaCl was studied by potentiodynamic polarization experiment and inductively coupled plasma emission spectroscopy. In this paper, the potentiodynamic polarization curve is analyzed from the perspective of corrosion type and corrosion control. Combined with x-ray photoelectron spectroscopy, the change in corrosion current density in AlCuxNiTiZr films is explained. [ABSTRACT FROM AUTHOR]

C21H25ClO, orthorhombic, Pna21 (no. 33), a = 14.152(2) Å, b = 22.112(3) Å, c = 6.0109(7) Å, V = 1880.9(4) Å3, Z = 4, Rgt(F) = 0.0586, wRref(F2) = 0.1227, T = 150 K. [ABSTRACT FROM AUTHOR]

Ordered mesoporous carbon (CMK-3) was fabricated by a simple nanocasting method using SBA-15 as a hard template. The CMK-3 had a two-dimensional hexagonal mesoporous structure and a specific surface area of approximately 975.9 m g. The CMK-3 was modified by HNO solutions with magnetic stirring and ultrasonic activation, respectively, to explore the influence of various activation methods on pore structure, surface state, morphology, and electrochemical performance. The CMK-3 modified by ultrasonic activation (CMK-3-US) reached the optimal specific capacitance of 233.4 A g at 0.5 A g and retained 94.2% after 500 cycles in 3 M KOH electrolyte. Furthermore, a symmetric supercapacitor was successfully assembled using CMK-3-US electrodes, which delivered an excellent energy density of 21.5 Wh kg at a power density of 225 W kg and exhibited great long-term stability with 97.5% retention after 4000 cycles. Compared to magnetic stirring activation, ultrasonic cavitation could better increase the efficiency of the HNO activation for mesoporous carbon particles. The results indicate ultrasonic activation is an efficient way to modify carbon-based electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]