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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： Mei Zhang Wenhao Li Yangfei Chen Yang Jiang Xiaofei Guo Han dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(rA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized rA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier *** volume fraction of rA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

Intermolecular reductive coupling of aliphatic ketones with alkynes and alkenes by BCN photocatalysts

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Science china Chemistry 2025年第1期68卷 181-185页

作者： Yanping Xia Luyang Sun Jiajia Cheng Sibo Wang Meifang Zheng Xinchen Wang State key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University

A photocatalytic process was developed for intermolecular reductive coupling of aliphatic ketones with alkynes/alkenes to furnish tertiary alcohols. Mechanistic studies support that boron carbonitrides(BCN) promote the single electron reduction of unactivated aliphatic ketones to generate ketyl radicals with visible light irradiation, which then react with alkynes and alkenes to afford the allylic and aliphatic alcohols, respectively. The heterogeneous photocatalytic system is compatible with diverse substrates including pharmaceutical-related molecules(43 examples) with reusability and scale-up experiments, verifying the complementary synthetic utility of this method to the homogeneous catalysts.

关键词： aliphatic ketones ketyl radical intermolecular cross-coupling tertiary alcohols

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO2 photoreduction

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Science china Chemistry 2025年第1期68卷 201-208页

作者： Hui-Feng Wang Wen-Jie Shi Yu-Xin Yang Bao-Xia dong Tong-Bu Lu di-Chang Zhong School of Chemistry and Chemical Engineering Yangzhou University Institute for New Energy Materials and Low Carbon technologies School of Materials Science and Engineering Tianjin University of Technology

dinuclear metal synergistic catalysis （dMSC） has been proved powerful in boosting CO2reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework （MOF）,obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center （M-In）,three MOFs with dinuclear homometallic catalytic centers （MM-In）,and three MOFs with dinuclear heterometallic catalytic centers (MM’-In,M/M’=Co（II）,Ni（II）,Zn（II）).It was found that all these MOFs can serve as catalysts for photochemical CO2reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g-1h-1,which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the dMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened dMSC *** work reveals the relationship between dMSC effect and bimetal centers in CO2reduction,which provides new insights into the dMSC and paves a new way to design highly active catalysts for photochemical CO2reduction.

关键词： metal-organic frameworks dinuclear metal centers synergistic catalysis CO2 reduction photocatalysis

Flexible Strain Sensors with Ultra‑High Sensitivity and Wide range Enabled by Crack‑Modulated Electrical Pathways

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Nano-Micro Letters 2025年第3期17卷 246-264页

作者： Yunzhao Bai Yunlei Zhou Xuanyu Wu Mengfei Yin Liting Yin Shiyuan Qu Fan Zhang Kan Li YongAn Huang State key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China Flexible Electronics research Center Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China Hangzhou Institute of Technology Xidian UniversityHangzhou 311200People’s Republic of China School of Mechano‑Electronic Engineering Xidian UniversityXi’an 710071People’s Republic of China department of Aerospace and Mechanical Engineering University of Southern CaliforniaLos AngelesCA 90089USA

This study presents a breakthrough in flexible strain sensor technology with the development of an ultrahigh sensitivity and wide-range sensor,addressing the critical challenge of reconciling sensitivity with measurement *** by the structure of bamboo slips,we introduce a novel approach that utilises liquid metal to modulate the electrical pathways within a cracked platinum fabric *** resulting sensor demonstrates a gauge factor greater than 108 and a strain measurement capability exceeding 100%.The integration of patterned liquid metal enables customisable tuning of the sensor’s response,while the porous fabric structure ensures superior comfort and air permeability for the *** design not only optimises the sensor’s performance but also enhances the electrical stability that is essential for practical *** systematic investigation,we reveal the intrinsic mechanisms governing the sensor’s response,offering valuable insights for the design of wearable strain *** sensor’s exceptional performance across a spectrum of applications,from micro-strain to large-strain detection,highlights its potential for a wide range of real-world uses,demonstrating a significant advancement in the field of flexible electronics.

关键词： Flexible strain sensor Fabric Crack response regulation Epidermal device

direct Photolithography of WO_(x)Nanoparticles for High‑resolution Non‑Emissive displays

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Nano-Micro Letters 2025年第3期17卷 297-309页

作者： Chang Gu Guojian Yang Wenxuan Wang Aiyan Shi Wenjuan Fang Lei Qian Xiaofei Hu Ting Zhang Chaoyu Xiang Yu‑Mo Zhang Laboratory of Optoelectronic Information Technology and devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China Hangzhou Bay Laboratory of Advanced Nano‑Optoelectronic Materials and devices Qianwan Institute of CNITECHNingbo 315336People’s Republic of China Smart Materials for Architecture research Lab Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100People’s Republic of China University of Science and Technology of china Hefei 230026People’s Republic of China State key Lab of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012People’s Republic of China

High-resolution non-emissive displays based on electrochromic tungsten oxides(WOx)are crucial for future near-eye virtual/augmented reality interactions,given their impressive attributes such as high environmental stability,ideal outdoor readability,and low energy ***,the limited intrinsic structure of inorganic materials has presented a significant challenge in achieving precise patterning/pixelation at the micron ***,we successfully developed the direct photolithography for WOx nanoparticles based on in situ photo-induced ligand *** strategy enabled us to achieve ultra-high resolution efficiently(line widthresolution for reported inorganic electrochromic materials).Additionally,the resulting device exhibited impressive electrochromic performance,such as fast response(ration efficiency(119.5 cm^(2) C^(−1)),good optical modulation(55.9%),and durability(>3600 cycles),as well as promising applications in electronic logos,pixelated displays,flexible electronics,*** success and advancements presented here are expected to inspire and accelerate research and development(r&d)in high-resolution non-emissive displays and other ultra-fine micro-electronics.

关键词： Electrochromic direct photolithography WOx nanoparticles In situ photo-induced ligand exchange High-resolution displays

Optimizing Fine-Tuning in Quantized Language Models:An In-depth Analysis of key Variables

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Computers, Materials & Continua 2025年第1期82卷 307-325页

作者： Ao Shen Zhiquan Lai dongsheng Li Xiaoyu Hu national key Laboratory of Parallel and distributed Computing National University of Defense TechnologyChangsha410073China Strategic Assessments and Consultation Institute Academy of Military ScienceBeijing100091China

Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning *** this approach allows models to specialize in specific tasks with reduced training costs,the substantial memory requirements during fine-tuning present a barrier to broader ***-Efficient Fine-Tuning(PEFT)techniques,such as Low-rank Adaptation(LorA),and parameter quantization methods have emerged as solutions to address these challenges by optimizing memory usage and computational *** these,QLorA,which combines PEFT and quantization,has demonstrated notable success in reducing memory footprints during fine-tuning,prompting the development of various QLorA *** these advancements,the quantitative impact of key variables on the fine-tuning performance of quantized LLMs remains *** study presents a comprehensive analysis of these key variables,focusing on their influence across different layer types and depths within LLM *** investigation uncovers several critical findings:(1)Larger layers,such as MLP layers,can maintain performance despite reductions in adapter rank,while smaller layers,like self-attention layers,aremore sensitive to such changes;(2)The effectiveness of balancing factors depends more on specific values rather than layer type or depth;(3)In quantization-aware fine-tuning,larger layers can effectively utilize smaller adapters,whereas smaller layers struggle to do *** insights suggest that layer type is a more significant determinant of fine-tuning success than layer depth when optimizing quantized ***,for the same discount of trainable parameters,reducing the trainable parameters in a larger layer is more effective in preserving fine-tuning accuracy than in a smaller *** study provides valuable guidance for more efficient fine-tuning strategies and opens avenues for further research into optimizing LLM

关键词： Large-scale Language Model Parameter-Efficient Fine-Tuning parameter quantization key variable trainable parameters experimental analysis

A robust statistical prediction model for late-summer heavy precipitation days in North china

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Science china Earth Sciences 2025年第1期68卷 158-171页

作者： Shunli JIANG Tingting HAN Xin ZHOU Huijun WANG Zhicong YIN Xiaolei SONG Collaborative Innovation Center on Forecast and Evaluation of Meteorological disasters/key Laboratory of Meteorological disaster Ministry of Education Nanjing University for Information Science and Technology Nansen-Zhu International research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)

recently, heavy precipitation(HP) events have occurred frequently in North china(NC), causing devastating economic losses and human fatalities. However, the short-term climate prediction of HP is quite limited. Combining year-to-year increment(dY) method and sliding correlations, we developed a robust seasonal prediction model for late-summer HP days(HPds) in NC during 1982–2022, utilizing three independent predictors—February sea surface temperature(SST) in the Indian Ocean(SST＿IO), February snow depth over North Asia(SdE＿NA), and May melted snow depth in NC(MSdE＿NC). The SST＿IO anomalies affect NC's precipitation through the Pacific-Japan pattern. The SdE＿NA anomalies are associated with East Asian anomalous anticyclone by southeastern propagation of rossby wave at Eurasia. The MSdE＿NC anomalies are followed by vertical motion and moisture anomalies in situ and thereby cause precipitation anomalies. This prediction model can well simulate the variations of the HPds, with a correlation coefficient(CC) of 0.81(0.65) between the observed and predicted HPds＿dY(HPds＿anomaly). The percentage with the same sign for 15 extreme HPds＿anomaly years(PSSE) is 100%.Moreover, in the cross-validation test during 1982–2022, the PSSE for HPds＿anomaly is as high as 100%, along with a low rootmean-square error of 1.14. For independent hindcasts during 2013–2022, the CC between the observed and predicted HPds＿dY(HPds＿anomaly) is 0.93(0.83), together with high Nash-Sutcliffe efficiency(0.82) and agreement index(0.89). Specifically, the predictions are broadly consistent with the observations for 2015, 2016, 2017, 2021, and 2022, reflecting excellent performance of this prediction model of HPds in NC.

关键词： Heavy precipitation at North china Year-to-year increment approach robust seasonal prediction Sea surface temperature Snow depth

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Establishing a new testing protocol of the electrochemical stability window for electric double-layer capacitors

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Science china Chemistry 2025年第1期68卷 217-225页

作者： ruilin Hou Xiaoxi Zhao Tingting Liang Qingyun dou Shan Xu Xingbin Yan School of Materials Science and Engineering Sun Yat-sen University Laboratory of Clean Energy Chemistry and Materials Lanzhou Institute of Chemical Physics Chinese Academy of Sciences College of Engineering and Applied Sciences Nanjing University Center of Industrial Analysis and Testing Guangdong Academy of Science

The electrochemical stability window(ESW) is crucial for determining the energy density of electric double-layer capacitors(EdLCs). However, current ESW testing protocols of EdLCs are strongly affected by artificial factors, thereby leading to unreliable result. To solve this problem, we first identify the key shortcomings of the traditional protocols by analyzing their test principles. Subsequently, taking an aqueous carbon-based EdLC as an example, we design a side reaction descriptor to represent the response difference in the charging capacitance to side reactions between the cyclic voltammetry and galvanostatic chargedischarge methods. With the aid of this descriptor, we propose a new ESW testing protocol, which is not only able to completely avoid the adverse influence of subjective factors but also fully consider the operating condition limitations. The protocol can be extended from the single electrode to the full device. This work proposes a more rigorous definition of ESW and provides a reliable protocol for evaluating the ESW of EdLCs.

关键词： electric double-layer capacitors electrochemical stability window testing protocol side reaction descriptor operating limitation

The detection, extraction and parameter estimation of extreme-mass-ratio inspirals with deep learning

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Science china(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 86-96页

作者： Qianyun Yun Wen-Biao Han Yi-Yang Guo He Wang Minghui du Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physics and Astronomy Shanghai Jiao Tong University School of Astronomy and Space Science University of Chinese Academy of Sciences Taiji Laboratory for Gravitational Wave Universe (Beijing/Hangzhou) University of Chinese Academy of Sciences Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Province Key Laboratory of Quantum Theory and Applications of MoE Lanzhou University Institute of Theoretical Physics & research Center of Gravitation Lanzhou University International Centre for Theoretical Physics Asia-Pacific (ICTP-AP) University of Chinese Academy of Sciences (UCAS) Center for Gravitational Wave Experiment National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences

One of the primary goals of space-borne gravitational wave detectors is to detect and analyze extreme-mass-ratio inspirals(EMrIs). This task is particularly challenging because EMrI signals are complex, lengthy, and faint. In this work, we introduce a2-layer convolutional neural network(CNN) approach to detect EMrI signals for space-borne detectors, achieving a true positive rate(TPr) of 96.9% at a 1% false positive rate(FPr) for signal-to-noise ratio(SNr) from 50 to 100. Especially, the key intrinsic parameters of EMrIs such as the mass, spin of the supermassive black hole(SMBH) and the initial eccentricity of the orbit can also be inferred directly by employing a neural network. The mass and spin of the SMBH can be determined at 99% and 92% respectively. This will greatly reduce the parameter spaces and computing cost for the following Bayesian parameter *** model also has a low dependency on the accuracy of the waveform model. This study underscores the potential of deep learning methods in EMrI data analysis, enabling the rapid detection of EMrI signals and efficient parameter estimation.

关键词： gravitational wave EMrIs deep-learing

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40卷 246-257页

作者： ZHANG Jian NIE Wei HUANG Jin ZHU Ke LIU ruxia ZHANG ruizhi LUO Guoqiang SHEN Qiang State key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W_(8)Ti_(8) are 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.

关键词： first-principles mechanical properties thermodynamic properties tungsten-titanium alloys