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Gradient maturation experiment on hairs implies taphonomic changes in fossil hairs

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Science China Earth Sciences 2025年第1期68卷 62-73页

作者： Xin LI Yibo ZHOU Tao ZHAO Xingjian HE Yanhong PAN State Key Laboratory for Mineral Deposits research Center for Critical Earth Material Cycling Centre for Research and Education on Biological Evolution and Environment and Frontiers Science School of Earth Sciences and Engineering Nanjing University institute of Palaeontology Yunnan Key Laboratory of Earth System Science Yunnan Key Laboratory for PalaeobiologyYunnan University

Mammalian hair, as a key feature related to endothermy, physical protection, and camouflage, has a long geohistorical record that dates back even to the Mesozoic. However, the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep time. To address this, we conducted taphonomic experiments to simulate the transformation process of black hair. The changes in the morphological structure, microscopic characteristics, and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy, Fourier transform infrared(FTIR) spectroscopy, and Raman spectroscopy. Our results revealed that damage to the morphology of hair began at a mild temperature(150–175°C), and hair transformed into a fluid-like mass at a relatively high temperature(200°C). In addition, the morphological structure of melanosomes had relatively greater preservation potential than keratins did, and the microscopic features of melanosomes were persistently stable. The Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature increased. Although the chemical signals were not lost completely, the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200°C), whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable, even at high temperatures(>200°C). These results were confirmed by principal component analysis(PCA) and principal component analysis linear discriminant analysis(PCA–LDA). In addition, the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid), which suggested that Raman spectroscopy can be used to detect melanin in fossils.

关键词： Mammalian hair Melanin Keratin Fossilization Experimental taphonomy

Impact of Bubbles on Mechanical Performances in a Borosilicate Glass

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 25-29页

作者： LI Chengxing LI Dongfeng MA Shilong QIAO Ang ZHENG Qingshuang China Helicopter research and Development institute Jingdezhen 333001China State Key Laboratory of Silicate Materials for Ar-chitectures Wuhan University of TechnologyWuhan 430070China

To analyze the impact of bubbles on the mechanical behavior of glasses,by controlling the refining time,we prepared three borosilicate glasses with the same composition and different *** the analysis software integrated within the optical microscope,the diameter and number of the bubbles on the surface of three borosilicate glasses were *** the hardness and crack initiation resistance(CR),we built the relationship between the porosity and the mechanical performance of these borosilicate glasses.

关键词： bubbles oxide glass hardness creak initiation resistance

IoT Empowered Early Warning of Transmission Line Galloping Based on Integrated Optical Fiber Sensing and Weather Forecast Time Series Data

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Computers, Materials & Continua 2025年第1期82卷 1171-1192页

作者： Zhe Li Yun Liang Jinyu Wang Yang Gao State Grid Henan Electric Power Company Electric Power Scientific research institute State Grid Henan Electric Power CompanyZhengzhou450052China

Iced transmission line galloping poses a significant threat to the safety and reliability of power systems,leading directly to line tripping,disconnections,and power *** early warning methods of iced transmission line galloping suffer from issues such as reliance on a single data source,neglect of irregular time series,and lack of attention-based closed-loop feedback,resulting in high rates of missed and false *** address these challenges,we propose an Internet of Things(IoT)empowered early warning method of transmission line galloping that integrates time series data from optical fiber sensing and weather ***,the method applies a primary adaptive weighted fusion to the IoT empowered optical fiber real-time sensing data and weather forecast data,followed by a secondary fusion based on a Back Propagation(BP)neural network,and uses the K-medoids algorithm for clustering the fused ***,an adaptive irregular time series perception adjustment module is introduced into the traditional Gated Recurrent Unit(GRU)network,and closed-loop feedback based on attentionmechanism is employed to update network parameters through gradient feedback of the loss function,enabling closed-loop training and time series data prediction of the GRU network ***,considering various types of prediction data and the duration of icing,an iced transmission line galloping risk coefficient is established,and warnings are categorized based on this ***,using an IoT-driven realistic dataset of iced transmission line galloping,the effectiveness of the proposed method is validated through multi-dimensional simulation scenarios.

关键词： Optical fiber sensing multi-source data fusion early warning of galloping time series data IoT adaptive weighted learning irregular time series perception closed-loop attention mechanism

High-performance poly(aromatic pyridine) copolymers with crown ether moieties for high temperature polymer electrolyte membrane fuel cells

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Science China Chemistry 2025年

作者： Qian Wang Songhao Zhao Yunpeng Guo Wei Wei Lele Wang Jingshuai Yang Department of Chemistry College of Sciences Northeastern University institute of Metal research Chinese Academy of Sciences

This study concentrates on the development of high temperature polymer electrolyte membranes（HT-PEMs）, which are essential components for HT-PEM fuel cells（HT-PEMFCs）. Although the phosphoric acid（PA）-doped polybenzimidazole（PBI） has been regarded as the successful HT-PEM, this system still suffers from several challenges, including the use of carcinogenic monomers, complex synthesis procedures, and poor solubility in organic solvents. To develop more cost-effective, readily synthesized and high-performance alternatives, this study employs a simply superacid-catalyzed Friedel-Crafts reaction to synthesize a series of poly（triphenyl-co-dibenzo-18-crown-6 pyridine） copolymers, denoted as P(TPx%-co-CEy%), using ptriphenyl, dibenzo-18-crown-6 and 4-acetylpyridine as monomers. The copolymerized hydrophilic and bulky crown ether unites introduce large free volumes and multiple interaction sites with PA molecules, as elucidated by theoretical *** microphase separation structures are formed as confirmed by atomic force microscope（AFM）, transmission electron microscopy（TEM） and small-angle X-ray scattering（SAXS）. Thus P(TPx%-co-CEy%) membranes exhibit excellent PA absorption and proton conduction abilities. For example, after immersing in 85 wt% PA at 30 °C, the P(TP91%-co-CE9%) membrane achieves a PA doping content of 205% and a high conductivity of 0.138 S cm-1at 180 °C, while maintaining a tensile strength of 7.5 MPa at room temperature. Without humidification and backpressure, the peak power density of an H2-O2cell equipped with P(TP91%-co-CE9%)/205%PA reaches nearly 1200 mW cm-2, representing one of the highest performances reported for PA-doped HT-PEMs to date. This work demonstrates the enormous potential of poly（triphenyl-co-crown ether pyridine） membranes in the HT-PEMFC applications.

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Energy management strategy that optimizes battery degradation for electric vehicles with hybrid energy storage system

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Science China Technological Sciences 2025年

作者： Jian WANG Chaofeng PAN Zhongxing LI School of Automotive and Traffic Engineering Jiangsu University Automotive Engineering research institute Jiangsu University

The short life of electric vehicle (EV) batteries is an important factor limiting the popularization of EVs. A hybrid energy storage system (HESS) for EVs combines Li-ion batteries with supercapacitors, so that the supercapacitor shares the peak power during the starting and braking, effectively solving the problem of irreversible capacity degradation of Li-ion batteries. Herein, an energy management strategy for HESS was designed based on battery degradation to extend the service life of the EV battery. First, to obtain accurate battery degradation characteristics, a cycling charge–discharge test was *** this test, the effects of discharge rate and state of charge on battery degradation rate were determined, and the battery degradation model was constructed. Based on the working map of the motor obtained through the bench test, a data-based model of the power system was constructed to accurately characterize the energy consumption of the EV under different operating conditions. Second, rule-based and optimization-based energy management strategies that consider battery degradation were designed using the fuzzy algorithm and dynamic programming (DP) algorithm. The effectiveness of the devised control strategies was assessed using the model-in-the-loop and hardware-in-the-loop test platforms. The fuzzy control strategy had a simple structure and could be rapidly calculated but showed worse performance than the DP-based strategy in terms of battery degradation. The DP-based energy management strategy resulted in 16.68%lower capacity degradation than the fuzzy strategy.

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Effect of Bi/Si Ratio of BiBSi Glass on Its Structure, Properties and Laser Sealing Shear Strength for Vacuum Glazing

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 13-24页

作者： LIU Wei JIAO Jinxu LUO Dusha ZHOU Junjie SHI Lifen WANG Weiwei LI Changqing WANG Peng XIONG Dehua LI Hong State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Silica-Based Materials Laboratory of Anhui Province CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China State Key Laboratory of Advanced Technology for Float Glass CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China

The low-melting glass of Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi)system was used for the first time for laser sealing of vacuum *** the condition of constant boron content,how the structure and properties vary with Bi/Si ratio in low-melting glass was *** addition,the relationships between laser power,low-melting glass solder with different Bi/Si ratios and laser sealing shear strength were *** results show that a decrease in the Bi/Si ratio can cause a contraction of the glass network of the low-melting glass,leading to an increase of its characteristic temperature and a decrease of its coefficient of thermal *** laser sealing,the copper ions in the low-melting glass play an endothermic role.A change in the Bi/Si ratio will affect the valence state transition of the copper ions in the low-melting *** absorbance of the low-melting glass does not follow the expected correlation with the Bi/Si ratio,but shows a linear correlation with the content of divalent copper *** greater the concentration of divalent copper ions,the greater the absorbance of the low-melting glass,and the lower the laser power required for laser *** shear strength of the low melting glass solder after laser sealing was tested,and it was found that the maximum shear strength of Z1 glass sample was the highest up to 2.67 MPa.

关键词： Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi) Bi/Si ratio low-melting glass laser sealing vacuum glazing

Multi-layer multi-pass friction rolling additive manufacturing of Al alloy:Toward complex large-scale high-performance components

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 425-438页

作者： Haibin Liu Run Hou Chenghao Wu Ruishan Xie Shujun Chen College of Mechanical&Energy Engineering Beijing University of TechnologyBeijing 100124China Chongqing research institute of Beijing University of Technology Chongqing 401121China

At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass *** this study,multi-layer multi-pass FRAM-deposited alumin-um alloy samples were successfully prepared using a non-shoulder tool *** material flow behavior and microstructure of the over-lapped zone between adjacent layers and passes during multi-layer multi-pass FRAM deposition were studied using the hybrid 6061 and 5052 aluminum *** results showed that a mechanical interlocking structure was formed between the adjacent layers and the adja-cent passes in the overlapped center *** friction and rolling of the tool head led to different degrees of lateral flow and plastic deformation of the materials in the overlapped zone,which made the recrystallization degree in the left and right edge zones of the over-lapped zone the highest,followed by the overlapped center zone and the non-overlapped *** tensile strength of the overlapped zone exceeded 90%of that of the single-pass deposition *** is proved that although there are uneven grooves on the surface of the over-lapping area during multi-layer and multi-pass deposition,they can be filled by the flow of materials during the deposition of the next lay-er,thus ensuring the dense microstructure and excellent mechanical properties of the overlapping *** multi-layer multi-pass FRAM deposition overcomes the limitation of deposition width and lays the foundation for the future deposition of large-scale high-performance components.

关键词： aluminum alloy additive manufacturing solid-state friction stir welding multi-layer multi-pass

Graphene oxide wrapped-silica microspheres humidity sensor with fast response/recovery, high sensitivity, and selectivity for pig respiratory rate monitoring

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Science China Technological Sciences 2025年

作者： Jing LI Bo LI Ziqi LIAO Yunhui DUAN Xinglan FU Yuehua HUANG Guanglin LI College of Engineering and Technology Southwest University Modern Agricultural Equipment research institute Xihua University

Respiratory rate monitoring is of great significance in pig healthy breeding for the early detection and timely prevention of respiratory diseases. Humidity sensing is an important noncontact method to monitor pig respiration, which does not cause direct harm to pigs and meets the requirements of animal welfare. This paper proposes a humidity sensor based on graphene oxide wrapped-silica microspheres （GO@SiO2）. First, the sensor shows fast response/recovery performances of0.24/0.73 s. Experiments demonstrate that the wrapped microsphere structure can inhibit water aggregation. It is speculated that the wrapped microsphere structure can inhibit the stacking of GO, and its curved surface can promote the evaporation of water molecules. Second, the sensor shows a high sensitivity of 1.2%/%RH–4.2%/%RH in 11%–95%RH range. This can be attributed to different sensing mechanisms, from hopping transport to increasing ion transport, leading to a significant change in the sensor’s resistance. Third, the sensor shows selectivity to water molecules due to the hydrophilic characteristic of GO and the significant increase in conductivity by ion transport. Finally, the sensor is applied to realize the respiratory rate monitoring of adult pigs and piglets.

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First observation results of Macao Science Satellite-1 on lightning-induced electron precipitation

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Science China Earth Sciences 2025年第1期68卷 1-10页

作者： Yongping WANG Yixin SUN Qiugang ZONG Gaopeng LU Xudong GU Ze-Jun HU Bin LI Key Laboratory for Polar Science Ministry of Natural Resources Polar Research Institute of China institute of Space Physics and Applied Technology Peking University State Key Laboratory of Lunar and Planetary Science Macau University of Science and Technology School of Earth and Space Sciences University of Science and Technology of China School of Electronic Information Wuhan University

The Medium-energy Electron Spectrometers(MES) is a space-borne instrument onboard Macao Science Satellite-1(MSS-1) dedicated to monitoring the typical charged particle radiation characteristics in the satellite orbit and the process of their occurrence and development, including short bursts of lightning-induced electron precipitation(LEP).This paper presents the first results of the LEP measurements by the MSS-1.47 LEP events are identified with the routine operation for 3 months since satellite launch, all within the range of 1.5

关键词： Lightning-induced electron precipitation Inner radiation belts Energetic electrons Macao Science Satellite-1