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Ameliorating the Strength-Modulus Synergy in GNPs Reinforced Mg-Zn-Zr Composites via Multidirectional Forging and Hot Extrusion Deformation

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 425-437页

作者： Yuhao Chen Kaibo Nie Kunkun Deng Zhilong Liu Quanxin Shi College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China state key laboratory of compressor technology(compressor technology laboratory of Anhui Province) Hefei 230031China Instrumental Analysis Center Taiyuan University of TechnologyTaiyuan 030024China

The integration of lightweight and high-modulus magnesium-based materials is becoming increasingly valued as structural materials due to the complexity and intelligence of industrial products like automobiles and *** this study,the graphene nanoplatelets(GNPs)/Mg-Zn-Zr composites with 0.5 wt%GNPs were successfully prepared by the combination of multidirectional forging(MDF)and hot extrusion(Ex).The newly-developed composites after multi-step deformation possessed excellent strength and modulus,with a tensile strength exceeding 375 MPa and an elastic modulus reaching 54 *** results revealed that the stripping and thinning of GNPs bands parallel to the extrusion direction occurred after MDF+Ex,which promoted the dynamic recrystallization and the formation of numerous fine *** significant improvement in comprehensive mechanical performances of the composites could be primarily ascribed to the refinement of grain size caused by the optimized distribution of GNPs,and efficient load transfer facilitated by the tight interface.

关键词： Magnesium matrix composites Graphene nanoplatelets(GNPs) Multi-step deformation Microstructure Strength-modulus

De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

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Science China Chemistry 2025年第1期 174-180页

作者： Fan-Xiao Meng Xing-Yu Wang Ka Lu Ju-Song Yang Fu-Min Zhang Ai-Jun Ma Bao Du Yong-Qiang Tu state key laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of Biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

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Real-time modular dynamic modeling for compression system of altitude ground test facilities

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Chinese Journal of Aeronautics 2023年第5期36卷 202-211页

作者： Yang SU Xuejiang CHEN Xin WANG Xiaodong LI Xiaoming LIU School of Energy and Power Engineering Xi’an Jiaotong UniversityXi’an 710049China AECC Sichuan Gas Turbine Establishment Mianyang 621703China state key laboratory of compressor technology(compressor technology laboratory of Anhui Province) Hefei 230031China

Modeling of a centrifugal compressor is of great significance to surge characteristics and fluid dynamics in the Altitude Ground Test Facilities(AGTF).Real-time Modular Dynamic System Greitzer(MDSG)modeling for dynamic response and simulation of the compression system is *** centrifugal compressor,pipeline network,and valve are divided into pressure output type and mass flow output type for module modeling,and the two types of components alternate when the system is *** pressure loss and thermodynamics of the system are *** air supply compression system of AGTF is modeled and simulated by the MDSG *** simulation results of mass flow,pressure,and temperature are compared with the experimental results,and the error is less than 5%,which demonstrates the reliability,practicability,and universality of the MDSG model.

关键词： Altitude Ground Test Facilities(AGTF) Compression modeling Dynamic simulation Real-time modelling Modular Dynamic System Greitzer(MDSG)modeling

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Effect of Ti Additions on Mechanical and Thermodynamic Properties of W-Ti Alloys:A First-principles Study

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Journal of Wuhan University of technology(Materials Science) 2025年第1期 246-257页

作者：张建 NIE Wei HUANG Jin ZHU Ke LIU Ruxia 张睿智 LUO Guoqiang SHEN Qiang state key laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of Technology Institute for Carbon Neutrality University of Science and Technology Beijing

The mechanical and thermodynamic properties of W-Ti alloys (including W15Ti1,W14Ti2,W12Ti4and W8Ti8alloys) were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W8Ti8are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.

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Exploring the interaction between the gut microbiota and cyclic adenosine monophosphate-protein kinase A signaling pathway:a potential therapeutic approach for neurodegenerative diseases

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Neural Regeneration Research 2025年第11期20卷 3095-3112页

作者： Fengcheng Deng Dan Yang Lingxi Qing Yifei Chen Jilian Zou Meiling Jia Qian Wang Runda Jiang Lihua Huang College of Pharmacy Chengdu University of Traditional Chinese MedicineChengduSichuan ProvinceChina state key laboratory of Southwestern Chinese Medicine Resources Chengdu University of Traditional Chinese MedicineChengduSichuan ProvinceChina

The interaction between the gut microbiota and cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)signaling pathway in the host's central nervous system plays a crucial role in neurological diseases and enhances communication along the gut–brain *** gut microbiota influences the cAMP-PKA signaling pathway through its metabolites,which activates the vagus nerve and modulates the immune and neuroendocrine ***,alterations in the cAMP-PKA signaling pathway can affect the composition of the gut microbiota,creating a dynamic network of microbial-host *** reciprocal regulation affects neurodevelopment,neurotransmitter control,and behavioral traits,thus playing a role in the modulation of neurological *** coordinated activity of the gut microbiota and the cAMP-PKA signaling pathway regulates processes such as amyloid-β protein aggregation,mitochondrial dysfunction,abnormal energy metabolism,microglial activation,oxidative stress,and neurotransmitter release,which collectively influence the onset and progression of neurological *** study explores the complex interplay between the gut microbiota and cAMP-PKA signaling pathway,along with its implications for potential therapeutic interventions in neurological *** pharmacological research has shown that restoring the balance between gut flora and cAMP-PKA signaling pathway may improve outcomes in neurodegenerative diseases and emotional *** can be achieved through various methods such as dietary modifications,probiotic supplements,Chinese herbal extracts,combinations of Chinese herbs,and innovative dosage *** findings suggest that regulating the gut microbiota and cAMP-PKA signaling pathway may provide valuable evidence for developing novel therapeutic approaches for neurodegenerative diseases.

关键词： cyclic adenosine monophosphate emotional disorders gut microbiota neurodegenerative diseases neurological diseases protein kinase A reciprocal regulation signaling pathway strategy therapies

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An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao National laboratory of Solid state Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China key laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

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Simulations of electron zebra stripes in the inner radiation belt using a composite empirical electric field model

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Science China Earth Sciences 2025年第1期 27-38页

作者： Ziyang WANG Ying LIU Qiugang ZONG Hong ZOU Yuguang YE Xuzhi ZHOU Chao YUE Shan WANG Institute of Space Physics and Applied technology Peking University state key laboratory of Lunar and Planetary Science Macau University of Science and Technology

The phenomenon termed “zebra stripes” manifests as regular patterns in the energy-space(L shell) spectrum of energetic electrons(ranging from tens to hundreds ke V) within the inner radiation belt. These structures exhibit drift-periodic behavior and commonly arise from large-scale electric field perturbations near the substorm onsets. In this study, we introduce a composite electric field model and replicate the formation, structure, and evolution of zebra stripes using a bounce-averaged test particle code under this electric field model. High-resolution measurements of energetic electrons obtained from the Van Allen Probes and the recently launched Macao Science Satellites-1 are used as initial conditions and served to validate our test particle simulations. Comparative analyses between observed data and simulations demonstrate our test particle method's efficacy in capturing zebra stripes' general behavior. Moreover, the composite model proves capable of reproducing realistic variations in the electric field within the inner radiation belt to a certain extent. Nevertheless, subtle differences emerge in the flux strength and the positions of stripes. These disparities primarily stem from limitations inherent in the electric field model and the initial conditions of the simulation. Acknowledging that the model represents an average case, it is conceivable that real-world scenarios may deviate from the average, thereby introducing variations in the observed phenomena.

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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 25-29页

作者：李成行 LI Dongfeng MA Shilong QIAO Ang 郑庆双 China Helicopter Research and Development Institute state key laboratory of Silicate Materials for Architectures Wuhan University of Technology

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.

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基于共价有机框架的分子工程高效光催化CO2还原为CO（英文）

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Science China Materials 2025年第1期 165-172页

作者：赵文玲孙磊杨丽张瑞玲任国庆王森吴昊康欣晨邓伟侨刘乘乘 Institute of Frontier Chemistry School of Chemistry and Chemical Engineering Shandong University Beijing National laboratory for Molecular Sciences Key Laboratory of Colloid and Interface and Thermodynamics Institute of Chemistry Chinese Academy of Sciences College of Chemistry Chemical Engineering and Resource Utilization Northeast Forestry University state key laboratory of Microbial technology Shandong University

共价有机框架广泛应用于光催化CO2还原中.然而,它们在分离光生载流子方面的效率有限,且催化位点较少,因此其光催化性能有待提高.本文利用分子工程设计了一种芘基共价有机框架（PyTa-H COF）,并将钴单原子（Co SACs）负载在COF骨架中用...

共价有机框架广泛应用于光催化CO2还原中.然而,它们在分离光生载流子方面的效率有限,且催化位点较少,因此其光催化性能有待提高.本文利用分子工程设计了一种芘基共价有机框架（PyTa-H COF）,并将钴单原子（Co SACs）负载在COF骨架中用于二氧化碳还原.在COF中,芘基团可以增强可见光捕获能力和电荷分离能力, Co SACs可以加速光生载流子的迁移及降低决速步的反应能垒.在可见光照射下,PyTa-H@Co在4小时内的CO产率为18.36 mmol g-1h-1,选择性为94%,其性能与目前报道的COFs的最佳性能相当.密度泛函理论计算表明,Co SACs稳定了*COOH中间体,并大大降低了决定性步骤的能垒,从而获得了优异的光催化性能.本工作通过分子工程设计,突出了催化剂结构和功能在提高光催化效率方面的重要作用.

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