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China Foundry 2025年

作者： Wen-tong Liu Yi-dong Wu Lei gao Jing-yang Chen Cheng-bo Xiao Xi-dong hui State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

The size and shape effect(SSE) of components has become a critical issue for mechanical properties, application reliability, and processing. In this study, the creep rupture life(CRL) of components with different wall thicknesses and positions in a combustion chamber casing simulator made of K439B superalloy was investigated. The intrinsic mechanisms of the SSE were explored from the dendrite structure, volume fraction and size of the γ' phase, and element segregation, etc. It is shown that this casting exhibits a strong SSE of creep rupture life, characterized by a significant difference in the CRL values up to 60% with the variation of wall thickness and position in the casing. In terms of casting technology, the influence of SSE on CRL is actually determined by the cooling rate. The SSE on the creep rupture life originates from the dendrite structure(such as the secondary dendrite arm spacing), volume fraction size of the γ' phase in the dendrite trunk, and elements segregation rate. This work may have implications for the design and application of engineering components with large sizes and complex structures.

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Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai Li Zhen Ma Jin-Hua gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： Xu Liang Ni-hui Zhang Zhi-Lai Zhan Guang-Lu Chang yan gao Xia Li Wen-Yuan gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

基于非对称流场流分离系统优化脂蛋白的分离条件

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北京大学学报（医学版） 2018年第3期50卷 564-571页

作者：吴迪邱百灵朱尘琪郭爽高杨亚雅梁启慧高也宋宇韩南银北京大学药学院化学生物学系北京100191

目的:使用自组装非对称流场流分离(asymmetrical flow field-flow fractionation,AF4)仪器对脂蛋白的分离条件进行优化,分析仪器的分离性能并验证载液黏度对分离效果的影响。方法:使用2种标准蛋白(碳酸酐酶和甲状腺球蛋白)初步验证自组... 详细信息

目的:使用自组装非对称流场流分离(asymmetrical flow field-flow fractionation,AF4)仪器对脂蛋白的分离条件进行优化,分析仪器的分离性能并验证载液黏度对分离效果的影响。方法:使用2种标准蛋白(碳酸酐酶和甲状腺球蛋白)初步验证自组装非对称流场流分离仪器的性能,标定分离通道相关参数(压制后的分离通道实际高度),进而通过四水平五因素的正交设计试验进行脂蛋白的分离条件优化,通过直观分析和方差分析评价差异具有统计学意义的影响因素,并对这些影响因素进行深入验证分析。结果:通过调节流速条件及载液条件得到碳酸酐酶和甲状腺球蛋白混合样品的分离图,根据流体动力学原理及Stoke’s公式计算得到分离通道高度为164μm。使用正交设计试验得到优化后的分离条件可实现高密度脂蛋白与低密度脂蛋白大于1.50的分离度(分离度为1.61和1.58),所选取的5种主要影响因素及其水平分别为分离总流速(3.00,3.50,4.00,4.50 m L/min)、聚焦时间(3.00,3.50,4.00,4.50 min)、过渡时间(0.5,1.0,1.5,2.0 min)、载液p H(6.8,7.00,7.20,7.40)、载液黏度(使用不同浓度的羟丙基甲基纤维素调节载液黏度,其浓度分别为0.00%,0.03%,0.06%,1.00%),正交设计试验结果显示,5种主要因素中载液黏度对分离度影响最大,结果差异具有统计学意义。进一步分析载液黏度的影响,发现增大黏度可有效提高分离度,但会带来增大负峰的作用。结论:自组装非对称流场流分离仪器可根据颗粒的粒径差异对脂蛋白进行有效分离,在优化的条件下可实现高、低密度脂蛋白的基线分离,载液黏度对分离度的影响差异具有统计学意义。

关键词：非对称流场流分离脂蛋白正交设计试验

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Macro-mechanics and Microstructure of Nanomaterial-modified Geopolymer Concrete: A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 204-214页

作者： WANG Tao FAN Xiangqian gao Changsheng QU Chiyu The National Key Laboratory of Water Disaster Prevention Nanjing Hydraulic Research InstituteNanjing 210024China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China School of Water Conservancy and Transportation Zhengzhou UniversityZhengzhou 450001China

We have described in detail the effects of nano-SiO_(2),nano-CaCO_(3),carbon nanotubes,and nano-Al_(2)O_(3) on geopolymer concrete from the perspectives of macro mechanics and *** existing research results show that the mechanism of nano-materials on geopolymer concrete mainly includes the filling effect,nucleation effect,and bridging effect,the appropriate amount of nano-materials can be used as fillers to reduce the porosity of geopolymer concrete,and can also react with Ca(OH)2 to produce C-S-H gel,thereby improving the mechanical properties of geopolymer *** optimum content of nano-SiO_(2) is between 1.0%and 2.0%.The optimum content of nano-CaCO_(3) is between 2.0%and 3.0%.The optimum content of carbon nanotubes is between 0.1%and 0.2%.The optimum content of nano-Al_(2)O_(3) is between 1.0%and 2.0%.The main problems existing in the research and application of nanomaterial-modified geopolymer concrete are summarized,which lays a foundation for the further application of nanomaterial in geopolymer concrete.

关键词： nanomaterials low carbon geopolymer concrete macro-mechanics microstructure

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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

Optimizing battery deployment: Aging trajectory prediction enabling homogenous performance grouping

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Journal of Energy Chemistry 2025年第1期100卷 565-577页

作者： Shuquan Wang Feng gao Zhan Ma Hao Tian Yusen Zhang School of Control Science and Engineering Shandong University Key Lab of Power System Intelligent Dispatch and Control of Ministry of Education Shandong University

As battery deployments in electric vehicles and energy storage systems grow, ensuring homogeneous performance across units is crucial. We propose a multi-derivative imaging fusion(MDIF) model, employing advanced imaging and machine learning to predict battery aging trajectories from minimal initial data, thus facilitating effective performance grouping before deployment. Utilizing a derivative strategy and Gramian Angular Difference Field for dimensional enhancement, the MDIF model uncovers subtle predictive features from discharge curve data after only ten cycles. The architecture includes a parallel convolutional neural network with lateral connections to enhance feature integration and *** on a self-developed dataset, the model achieves an average root-mean-square error of 0.047 Ah and an average mean absolute percentage error of 1.60%, demonstrating high precision and *** robustness is further validated through transfer learning on two publicly available datasets, adapting with minimal retraining. This approach significantly reduces the testing cycles required, lowering both time and costs associated with battery testing. By enabling precise battery behavior predictions with limited data, the MDIF model optimizes battery utilization and deployment strategies, enhancing system efficiency and sustainability.

关键词： Lithium-ion battery Battery prognostics Fusion model Convolutional neural network Transfer learning

Analysis and solution of streak effect in high dynamic range CMOS image sensors

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Science China(Information Sciences) 2025年第1期68卷 402-403页

作者： Wanbin ZHA Jiangtao XU Jinghua AO Kaiming NIE Zhiyuan gao School of Microelectronics Tianjin University Tianjin Key Laboratory of Imaging and Sensing Microelectronic Technology Tianjin University

The high dynamic range (HDR) CMOS image sensor has been widely used in many fields,such as autonomous driving and security guarding [1].The dual conversion gain (DCG)structure,which adjusts the conversion gain (CG) by changing the capacitors connected to the floating diffusion (FD)nodes in the pixel,is an effective and prevalent method for realizing HDR imaging [2].While the DCG structure can extend the dynamic range,in the practical HDR imaging process,the substantial number of photo-generated electrons in bright areas can cause significant voltage variations in the pixel *** variations affect the gray values in darker areas of the same image,leading to the streak effect [3].This study primarily investigates the streak effect caused by forward conduction current of the PN junction in DCG pixels,and proposes a circuit to suppress this effect.

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Simulation and analysis of the long-term impacts of 1.5°C global climate pledges on China's land systems

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Science China Earth Sciences 2025年

作者： Jiaying LV Changqing SONG Yifan gao Sijing YE Peichao gao State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Center for GeoData and Analysis Beijing Normal University

Global warming has become a shared issue for humanity. At the 26th Conference of the Parties to the United Nations Framework Convention on Climate Change in 2021, participating countries reached climate pledges aimed at making more proactive contributions to limit the global average temperature rise within 1.5°C by 2100. Land system changes are significant responses of land to climate change. As one of the contracting parties, China has proposed climate targets such as carbon peaking and carbon neutrality goals in recent years to support the global pledges of limiting global warming to1.5°C, which will profoundly impact China's future land system changes. This study focuses on China as the study area,produces data with a thematic resolution of 27 types of land systems, integrates the output of various land types by the Global Change Assessment Model(GCAM) into four categories of land service demand, and combines these with the improved CLUMondo model to simulate China's land system changes in 2100 under a 1.5°C global warming scenario and a reference scenario without updated emission reduction measures. The conclusions of this study are as follows:(1) The method of integrating the GCAM and improved CLUMondo model demonstrates high validation accuracy in simulating China's land system changes, effectively predicting the changes.(2) Under the 1.5°C global warming scenario, the quality of ecosystems related to mountains, water, forests, farmland, lakes, and grasslands in China improved. The areas of shrubland, wetland, and forest are projected to increase by 185%, 79%, and 33%, respectively, with low-density shrubland, high-density wetland, and high-density forest showing the most significant increases.(3) Compared with the reference scenario, the 1.5°C climate pledges drive greater changes in future land systems, with wetland and forest area growth levels exceeding those of the reference scenario by 20% and 10%, respectively. Notably, the changes in cropland, grasslan

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Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： Qiang Liu Xiang Li Shen Du Ming gao yanbin Yin Jiongming Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity

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