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Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng Zheng Wang Ruisong Zhu Ruijie Liu Jiang Ma Lina Hu Weihua Wang Key Laboratory for Liquid-Solid structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University college of Mechatronics and Control engineering Shenzhen University Songshan Lake Materials Laboratory Institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

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A six-variable quasi-3D isogeometric approach for free vibration of functionally graded graphene origami-enabled auxetic metamaterial plates submerged in a fluid medium

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 157-176页

作者： Wei CHEN Zhihong TANG Yufen LIAO Linxin PENG college of Civil engineering University of South China college of Civil engineering and Architecture Guangxi University Key Laboratory of Disaster Prevention and structural Safety of Ministry of Education Guangxi University

This paper presents, for the first time, an effective numerical approach based on the isogeometric analysis(IGA) and the six-variable quasi-three dimensional(3D)higher-order shear deformation theory(HSDT) to study the free vibration characteristics of functionally-graded(FG) graphene origami(GOri)-enabled auxetic metamaterial(GOEAM) plates submerged in a fluid medium. The plate theory incorporates the thickness stretching and the effects of transverse shear deformation without using any shear correction factors. The velocity potential function and Bernoulli's equation are used to derive the hydrodynamic pressure acting on the plate surface. Both horizontally and vertically immersed plate configurations are considered here in the form of inertia *** plates are composed of multilayer GOEAMs, with the GOri content varying through the plate's thickness in a layer-wise manner. This design results in graded auxetic *** material properties are evaluated by mixing rules and a genetic programming(GP)-assisted micromechanical model. The governing equations of motion for the FG-GOEAM plates immersed in a fluid medium are derived by Hamilton's principle. After validating the convergence and accuracy of the present model, a comprehensive parametric study is carried out to examine the effects of the GOri content, GOri distribution pattern, GOri folding degree, fluid level, immersed depth, and geometric parameter on the natural frequencies of the FG-GOEAM plates. The results show that the natural frequencies for the four GOri distribution patterns increase with the increase in the layer number when the lay number is fewer than 10, and then stabilize after the layer number reaches ***, in general, the natural frequency of the FG-GOEAM plate in a vacuum or fluid increases when the GOri content increases, while decreases when the GOri folding degree increases. Some additional findings related to the numerical results are presented in the conclusions. It is belie

关键词： Equations of motion

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Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 123-138页

作者： Chentong GAO Huiyu SUN Jianping GU W.M.HUANG college of Aerospace engineering Nanjing University of Aeronautics and Astronautics School of Mechanical and Aerospace engineering Nanyang Technological University Jiangsu Key Laboratory of Advanced structural Materials and Application Technology School of Materials Science and EngineeringNanjing Institute of Technology

Currently, there are a limited number of dynamic models available for braided composite plates with large overall motions, despite the incorporation of three-dimensional(3D) braided composites into rotating blade components. In this paper, a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established. Based on Kirchhoff's plate assumptions, the displacement variables of the plate are expressed. By incorporating the braiding directions into the constitutive equation of the braided composites, the dynamic model of the plate considering braiding directions is obtained. The effects of the speeds, braiding directions, and braided angles on the responses of the plate with fixed-axis rotation and translational motion, respectively, are investigated. This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions. It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications.

关键词： Constitutive equations

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Enantioselective reductive conjugate alkenylation of α,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De He Yun-Lei Luo Qiu-Quan Pan Qi-Wei Yao Xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis, yet their asymmetric variant remains elusive. Concurrently, asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–M. This manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl acetates. The method facilitates the enantioselective addition of keto alkenyl groups to α,β-enones, resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access otherwise. The use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

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Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期68卷 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology college of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

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Negative PO3-implanted bionic ion transport channels for promoting Li-S battery

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Science China Chemistry 2025年

作者： Wenhuan Huang Shun Wang Xuehan Hou Yanan Zhang Xingxing Zhang Yaoxiao Zhao Xilang Jin Huabin Zhang Fei Wang Jian Zhang Key Laboratory of Chemical Additives for China National Light Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and Technology School of Materials and Chemical engineering Xi'an Technological University Chemistry Program Physical Science and Engineering Division King Abdullah University of Science and Technology State Key Laboratory of structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Lithium-sulfur （Li-S） battery,as a promising next-generation high-energy-density battery,suffers from lithium polysulfides（LPSs） shuttle and Li dendrites *** crystalline framework-based membranes as separator can effectively absorb and restrain LPSs but without precise structural design principal exploration and mechanism ***,bio-inspired 1D oriented lithium-ion transport channels with molecular negatively charged PO3（-1） have been developed in hybrid tetrazole frameworks for promoting the transmission of Li+*** theoretical calculations and in situ spectroscopy demonstrated the higher binding energy and inhibited diffusion of LPSs in *** assembled PP@PO3Janus separator in Li-S coin cell delivered a high initial capacity of 1410.9 mAh g-1at 0.1 C and a low attenuation rate of 0.038%per cycle over 500 cycles at 5 ***,the high capacities of 862,542 and 409 mAh g-1based on high-sulfur-loading cathodes of 2.6,3.8 and 5.0 mg cm-2at0.5 C were achieved,***,the punch battery of PO3@PP separator with S-cathode of 1.2 mg cm-2has been developed for demonstrating its potentials commercial application,which displays impressive capacity of 873.4 mAh g-1with the retention of～78.9%over 50 cycles.

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Breaking the structural symmetry of active sites in zeolite imidazolate framework for enhanced CO2 photoreduction

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Science China Chemistry 2025年

作者： Yupeng Han Yayu Yan Qiaohong Li Xin Wu Fei Wang Jian Zhang State Key Laboratory of structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences college of Chemistry Fuzhou University

Adjusting the structure and composition of active sites is a highly effective method for activating linear ***, precise control of interfacial chemistry within molecular-scale environments presents a significant challenge in heterogeneous catalysis. In our study, we present symmetry-broken Mo-O-Co triple-atom active sites within the hybrid zeolite imidazole framework HZIF-CoMo. These sites disrupt the electronic balance and create a weak built-in electric field, thus promoting photocatalytic CO2reduction. The CO yield over HZIF-CoMo is improved to 3.1 mmol g-1h-1, which is over four times higher than the parent cobalt-imidazole framework MAF-6-Co. Both experimental and theoretical studies indicate that electronic modulation through the symmetry-breaking Mo-O-Co moiety acts as an organizing knob to accelerate charge separation and result in more carriers participating in the catalytic reaction. This work provides important insights into optimizing site-related electronic structures for targeted photocatalytic reactions.

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Tribo-piezoelectric hybrid nanogenerator based on temporary solution template process

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Science China Technological Sciences 2025年

作者： Jinxian ZHANG Peng PAN Zhengchun YANG Jie HE Peifeng ZENG college of Integrated Circuit Science and engineering Tianjin University of Technology

In this study, a friction piezoelectric hybrid nanogenerator （HNG） with a sponge-like structure was developed. A novel temporary solution template process was proposed to create smaller, uniformly distributed pores within the sponge structure, allowing for the complete volatilization of the porous agent without causing structural defects. The output voltage of the porous HNG structure was nearly twice that of its solid structure, demonstrating superior electrical output performance. A peak-to-peak open circuit voltage of 168 V, a short circuit current density of 36.41μA cm-2, and a maximum power density of 32 W m-2were obtained at a load resistance of 200 MΩby periodically compressing an HNG with a dimension of 0.8 cm×0.8 cm. The generated electricity was sufficient to directly illuminate 180 tandem white LEDs and power small electronic devices. In addition, this study shows that the HNG could detect electrical signals from different parts of the human body during movement, suggesting significant potential for applications in energy harvesting and motion sensing.

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Recent progress in constructing fluorinated solid-electrolyte interphases for stable lithium metal anodes

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 270-291页

作者： Di Zhang Pengfei Lv Wei Qin Xin He Yuanhua He Civil Aircraft Fire Science and Safety engineering Key Laboratory of Sichuan Province College of Civil Aviation Safety EngineeringCivil Aviation Flight University of ChinaGuanghan 618307China School of Chemical engineering Sichuan UniversityChengdu 610065China

Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific ***,the non-uniform plating of lithium and the potential rupture of the solid-electrolyte interphase(SEI)during extended cycling use may result in dendrite growth,which can penetrate the separator and pose significant short-circuit *** a stable SEI is essential for the long-term operation of the ***-rich SEI has garnered significant attention for its ability to effectively passivate electrodes,regulate lithium deposition,and inhibit electrolyte *** the structural components and preparation methods of existing fluorinated SEI is crucial for optimizing lithium metal anode *** paper reviews the research on optimizing LiF passivation interfaces to protect lithium metal *** focuses on four types of compositions in fluorinated SEI that work synergistically to enhance SEI *** instance,combining compounds with LiF can further enhance the mechanical strength and ionic conductivity of the *** metals with LiF significantly improves electrochemical performance at the SEI/anode interface,with a necessary focus on reducing electron tunneling ***,incorporating polymers with LiF offers balanced improvements in interfacial toughness and ionic conductivity,though maintaining structural stability over long cycles remains a critical area for future *** alloys combined with LiF increase surface energy and lithium affinity,challenges such as dendrite growth and volume expansion *** summary,this paper emphasizes the crucial role of interfacial structures in LMBs and offers comprehensive guidance for future design and development efforts in battery technology.

关键词： LiF lithium metal anodes solid-electrolyte interphase interface cycling stability

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Dual-ligand chiral MOFs exhibiting circularly polarized room temperature phosphorescence for anti-counterfeiting

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Science China Chemistry 2025年

作者： Hongrui Zheng Qingqing Wang Xinchao Wang Fei Wang Shangda Li Jian Zhang State Key Laboratory of structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fujian Key Laboratory of Polymer Materials College of Chemistry and Materials Science Fujian Normal University

Advanced chiral optical materials exhibiting circularly polarized room-temperature phosphorescence（CPRTP） possess significant research value. This study facilitates the synthesis of chiral metal-organic frameworks（CMOFs） with good CPRTP performance by implementing a dual-ligand strategy. By self-assembling the luminescent ligand H2BIIM with the chiral ligands L-or D-H2IDPA in the presence of Zn（II） ions, two robust three-dimensional（3D） CMOFs were successfully constructed. These complexes demonstrated intense fluorescence and exhibited prolonged yellow room-temperature phosphorescence（RTP） with a duration of up to 6 s. Notably, they exhibited both circularly polarized fluorescence(glum= ±7.57 × 10-3) and CPRTP(glum=±2.68 × 10-3). These unique properties were effectively utilized in the creation of multi-color anti-counterfeiting patterns,underscoring their promising potential for a wide range of applications.

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