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The relationship between interfacial structure and thermal conductivity in epoxy resin/Al2O3 composite is important but is still elusive. Here, we illuminate this issue by investigating the role of four silane coupling agents in thermal conductivity for epoxy resin/Al2O3 composites. The results show that 3‐glycidoxypropyltrimethoxysilane (KH560) is the best silane coupling agent to modify Al2O3, resulting in the lowest viscosity and the highest thermal conductivity of the epoxy resin/Al2O3‐KH560 composite compared with alternative systems. This is attributed to the strong interfacial interaction between Al2O3‐KH560 and epoxy resin, as confirmed by the Fowkes model and broadband dielectric spectroscopy. The interfacial thermal resistance between the epoxy resin and Al2O3 is also quantitatively measured via a photothermal radiometry technique. The epoxy resin/Al2O3‐KH560 also has the lowest interfacial thermal resistance (1.50 ± 0.02 × 10−6 m2 K W−1), compared with the other three systems. This study advances the understanding of the relationship between interfacial structure and thermal conductivity in polymer composites. Highlights: The relationship between interfacial structure and thermal conductivity in epoxy resin/Al2O3 composite is understood.The interfacial structure is characterized by broadband dielectric spectroscopy.The interfacial thermal resistance is quantitatively measured via a photothermal radiometry technique. [ABSTRACT FROM AUTHOR]

Rare earth (RE)-doped BaTiO3 materials are promising dielectric materials for base-metal electrode multilayer ceramic capacitors (BME-MLCCs). Thus, the fundamental understanding of their effect on dielectric properties and reliability is crucial for further improvement of its performance. Herein, according to Preisach model, the dielectric stability of Dy and Y-doped BaTiO3 MLCCs with different particle sizes was investigated in this study. First order reversal curve (FORC) analysis showed that the reversible and irreversible domain wall motion of Dy-doped samples was weaker than that of Y-doped samples. Results also showed that the higher "shell" proportion of "core-shell" structure in Dy-doping was beneficial for improving the dielectric stability and insulation resistance degradation. The findings provide a comprehensive understanding and illustrate the significant role of the "core-shell" volume ratio in the tetragonality and domain wall motion in RE-doped BaTiO3 materials, and consequently laying an important ground work to obtain high dielectric stability and reliability in BME-MLCCs. [ABSTRACT FROM AUTHOR]

Background: Lung cancer (LC) is currently the number one malignancy death rate disease in China, and its disease burden is serious. The study aimed to analyze trends of LC and its risk factor attributable disease in China from 1990 to 2019 and predict the next 41 years. Methods: The average annual percentage change (AAPC) was used to analyze the trend of LC and its risk factor attributable incidence, deaths, and disability‐adjusted life years (DALYs) rate in China from 1990 to 2019, collected in the Global Burden of Disease 2019. Cochran–Armitage trends examine trends in lung cancer disease burden by sex, age, and attributable risk factor groups in China from 1990 to 2019. In addition, based on data on death and DALYs rate due to LC and its risk factors between 1990 and 2019, an autoregressive integrated moving average (ARIMA) model was developed to predict the change in the trend of burden of disease due to LC and its risk factors over the next 41 years, and the model was evaluated using the model parameters root mean square error, mean absolute error, and mean absolute percentage error. Results: From 1990 to 2019, the incidence, mortality and DALYs of LC were all increased. Among the eight risk factors associated with lung cancer, the DALYs rate and mortality rate of lung cancer risk factors for Chinese residents increased from 1990 to 2019, except for household air pollution from solid fuels and diet low in fruit, which showed a decrease; among them, the DALYs rate and mortality rate due to ambient particulate matter pollution showed the greatest increase with AAPC values of 2.880 and 3.310, respectively, while DALYs and mortality rates due to household air pollution from solid fuels showed the largest decreases, with AAPC values of −4.755 and −4.348, respectively. The results of the ARIMA model predictions show that both the mortality rate and the rate of DALYs for lung cancer are increasing yearly, and it is predicted that the rate of DALYs for lung cancer by 2060 will reach 740.095/100 000 and the mortality rate will reach 35.151/100 000. It is expected that by 2060, the top four risk factors for lung cancer in China will be, in order of DALYs rate and mortality rate, smoking, ambient particulate matter pollution, high fasting plasma glucose (HFPG), and secondhand smoke, with HFPG showing the greatest increase. Conclusions: The LC burden increased from 1990 to 2019 in China, the LC burden that could be attributed to HFPG will continue to increase in the next 40 years, and will be the third most factor by 2060. Targeted interventions are warranted to facilitate the prevention of LC and improvement of health‐related quality of life patients with LC. [ABSTRACT FROM AUTHOR]

The medium-intensity karst desertification environment is typically characterized by more rocks and less soil. The abandoned land in the construction areas of the dry-hot river valley hydropower station has more infertile soil, severe land degradation, and very low land productivity. Therefore, it is urgent to improve the soil quality to curb the increasingly degrading land and reuse the construction site. Few studies have focused on the effect of soil restoration and comprehensive evaluation of soil quality with multi-treatment in abandoned land in the dry-hot valley hydropower station construction area. Here, 9 soil restoration measures and 1 control group were installed at the Guangzhao Hydropower Station construction in Guizhou Province, China, for physical and chemical property analysis. In total, 180 physical and 90 chemical soil samples were collected on three occasions in May, August, and December 2022. Soil fertility and quality were evaluated under various measures using membership functions and principal component analysis (PCA). This study showed that almost all measures could enhance soil water storage capacity (The average total soil porosity of 9 soil treatments was 57.56%, while that of the control group was 56.37%). With the increase in soil porosity, soil evaporation became stronger, and soil water content decreased. Nevertheless, no decrease in soil water content was observed in the presence of vegetation cover (soil water content: 16.46% of hairy vetch, 13.99% of clover, 13.77% of the control). They also proved that manure, synthetic fertilizer, and straw could promote total and available nutrients (Soil total nutrient content, or the total content of TN、TP、TK,was presented as: synthetic fertilizer (11.039g kg-2)>fowl manure (10.953g kg-2)>maize straw (10.560g kg-2)>control (9.580g kg-2);Total available nutrient content in soil, or the total content of AN,AP,A,was shown as:fowl manure (1287.670 mg kg-1)>synthetic fertilizer (925.889 mg kg-1)>sheep manure (825.979 mg kg-1)>control (445.486 mg kg-1). They could also promote soil fertility, among which the first two reached the higher comprehensive soil quality. Fertilizer was conducive to improve soil quality and fertility, yet long-term application could cause land degradation like soil non-point source pollution, compaction, and land productivity decline. Ultimately, combining fertilizer with biochar or manure is recommended to improve soil fertility. Biochar and green manure could play an apparent role in soil improvement only when there is abundant soil water. The above views provide theoretical support for curbing soil degradation, improving soil fertility and quality, enhancing land productivity, and promoting the virtuous cycle of the soil ecosystem. [ABSTRACT FROM AUTHOR]

Elastomers are widely used for their large‐strain reversible stretchability, but their low thermal conductivity limits their applications in thermal management. Increasing the thermal conductivity of elastomers usually involves adding fillers, which deteriorate their stretchability and other desirable properties. Here, a supramolecular structure design strategy is proposed to enhance the thermal conductivity of amorphous elastomers without compromising their stretchability and self‐healing abilities. Supramolecular poly(thioctic acid‐N,N′‐methylenebis acrylamide) elastomers are designed with ordered hydrogen bonding interactions that improve the heat transfer efficiency and maintain excellent stretchability. The resulting elastomers exhibit a thermal conductivity of 0.72 W m−1 K−1, a remarkable stretchability of 427%, a low elastic modulus of 475 kPa, and self‐healing and reprocessing capabilities. This strategy offers a promising alternative for developing thermally conductive elastomers that do not rely on traditional fillers. [ABSTRACT FROM AUTHOR]

With the popularization of 5G technology and artificial intelligence, thermally conductive epoxies with self‐healing ability will be widely used in flexible electronic materials. Although many compounds containing both performances have been synthesized, there is little systematic theory to explain the coordination mechanism. In this paper, alkyl chains of different lengths were introduced to epoxies to discuss the thermally conductive, the self‐healing performance, and the synergistic effect. A series of electronic‐grade biphenyl epoxies (4,4′‐bis(oxiran‐2‐ylmethoxy)‐1,1′‐biphenyl (1), 4,4′‐bis(2‐(oxiran‐2‐yl)ethoxy)‐1,1′‐biphenyl (2), 4,4′‐bis(3‐(oxiran‐2‐yl)propoxy)‐1,1′‐biphenyl (3), and 4,4′‐bis(4‐(oxiran‐2‐yl)butoxy)‐1,1′‐biphenyl (4) were synthesized and characterized. Furthermore, they were cured with decanedioic acid to produce polymers. Results showed that alkyl chains can both affect the two properties, and the epoxies suitable for specific application scenarios can be prepared by adjusting the length of alkyl chains. In terms of thermal conductivity, compound 1 was a most promising material. However, compound 4 was expected to be utilized in flexible electronic devices because of its acceptable thermal conductivity, self‐healing ability, transparency, and flexibility. [ABSTRACT FROM AUTHOR]

2D magnetic materials hold substantial promise in information storage and neuromorphic device applications. However, achieving a 2D material with high Curie temperature (TC), environmental stability, and multi‐level magnetic states remains a challenge. This is particularly relevant for spintronic devices, which require multi‐level resistance states to enhance memory density and fulfil low power consumption and multi‐functionality. Here, the synthesis of 2D non‐layered triangular and hexagonal magnetite (Fe3O4) nanosheets are proposed with high TC and environmental stability, and demonstrate that the ultrathin triangular nanosheets show broad antiphase boundaries (bAPBs) and sharp antiphase boundaries (sAPBs), which induce multiple spin precession modes and multi‐level resistance. Conversely, the hexagonal nanosheets display slip bands with sAPBs associated with pinning effects, resulting in magnetic‐field‐driven spin texture reversal reminiscent of "0" and "1" switching signals. In support of the micromagnetic simulation, direct explanation is offer to the variation in multi‐level resistance under a microwave field, which is ascribed to the multi‐spin texture magnetization structure and the randomly distributed APBs within the material. These novel 2D magnetite nanosheets with unique spin textures and spin dynamics provide an exciting platform for constructing real multi‐level storage devices catering to emerging information storage and neuromorphic computing requirements. [ABSTRACT FROM AUTHOR]