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THEORETICAL PREDICTION OF PROEUTECTOID FERRITICTRANSFORMATION IN HYPO-PROEUTECTOID STRUCTRAL STEELS

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Acta Metallurgica Sinica(English Letters) 1998年第3期11卷 207-214页

作者： H.B.Chang z.g.li T.Y.Hsu z.Y.Xu X.Y.Ruan Shanghai Technical Coll of Metallurgy Shanghai China

Proeutectoid ferrite with carbon content xo precipitating from austenite in a multicomponent steel at temperature T is supposed to be equivalent to proeutectoid ferrite with the same carbon content precipitating from austenite in Fe-C binary system at temperature T'.is described as the temperature difference of proeutectiod ferrite formation, and can be calculated from the Fe-X diagrams and the equilibrium temperature A3. By introducing Tf and basing on the thermodynamic model for Fe-C binary alloy, the driving force for phase transformation from austenite to proeutectoid ferrite in multicomponent steels has been successfully calculated. Through the Johnson-Mehl equation and using the data hem known TTT diagrams, the relationship between the chemical composition and the intedecial edenly packeter as well as activation energy for proeutectoid ferrite formation can be calculated. The starting curves of proeutectoid ferritic transformation calculated in this way in some hypo-proeutectoid structural steels agree well with the erperimental data.

关键词： proeutectoid ferrite formation temperature difference interfacial enerpy parameters activation energy for diffusion Johnson-Mehl equation

对比增强乳腺X线摄影联合Kaiser评分对评估断层BI-RADS 4A病灶临床决策的价值

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国际医学放射学杂志 2023年第1期46卷 115-116页

作者： X.C.Rong Y.H.Kang J.Xue P.Y.Han z.g.li g.Yang 张慧慧

摘要目的探讨对比增强乳腺X线摄影(CEM)联合Kaiser评分(KS)对数字乳腺断层摄影(DBT)乳腺影像报告和数据系统(BI-RADS)4A病灶的诊断效能,以减少不必要

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Targeting epigenetic mechanisms in amyloid-β-mediated Alzheimer’s pathophysiology:unveiling therapeutic potential

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Neural Regeneration Research 2025年第1期20卷 54-66页

作者： Jennie z.li Nagendran Ramalingam Shaomin li Ann Romney Center for Neurologic Diseases Brigham and Women’s Hospital and Harvard Medical SchoolBostonMAUSA

Alzheimer’s disease is a prominent chronic neurodegenerative condition characterized by a gradual decline in memory leading to *** evidence suggests that Alzheimer’s disease is associated with accumulating various amyloid-βoligomers in the brain,influenced by complex genetic and environmental *** memory and cognitive deficits observed during the prodromal and mild cognitive impairment phases of Alzheimer’s disease are believed to primarily result from synaptic *** life,environmental factors can lead to enduring changes in gene expression and the emergence of brain *** changes,known as epigenetic modifications,also play a crucial role in regulating the formation of synapses and their adaptability in response to neuronal *** this context,we highlight recent advances in understanding the roles played by key components of the epigenetic machinery,specifically DNA methylation,histone modification,and microRNAs,in the development of Alzheimer’s disease,synaptic function,and activity-dependent synaptic ***,we explore various strategies,including enriched environments,exposure to non-invasive brain stimulation,and the use of pharmacological agents,aimed at improving synaptic function and enhancing long-term potentiation,a process integral to epigenetic ***,we deliberate on the development of effective epigenetic agents and safe therapeutic approaches for managing Alzheimer’s *** suggest that addressing Alzheimer’s disease may require distinct tailored epigenetic drugs targeting different disease stages or pathways rather than relying on a single drug.

关键词： Alzheimer’s disease DNA methylation enriched environments histone modification microRNAs non-invasive brain stimulation synaptic plasticity

Three-dimensional Morphology of Intragranular Ferrite in an Fe-C-Mn Alloy

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Three-dimensional Morphology of Intragranular Ferrite in an ...

Bioelectronic medicine in modulation of cortical spreading depolarization and beyond

第二届全国背散射电子衍射（EBSD）技术及其应用学术会议暨第六届全国材料科学与图像科技学术会议

作者： L.Cheng~1 z.g.li~2 K.M.Wu~1 1 Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Department of Applied Physics,Wuhan University of Science and Technology,Wuhan 430081,China. 2 Technology Center,Baosteel group,Shanghai 201900,China

Intragranular ferrite is an important microstructure in the transformation of weld metals, pipeline steels and other structural *** has a very good combination of high strength and toughness. Three-dimensional morphology of intragranular ferrite idiomorphs and plates or laths nucleated at inclusions in an Fe-0.09%C-1.48%Mn alloy was revealed by means of computer-aided three-dimensional reconstruction technique. Specimens were austenitized at 1250℃ under a purified argon atmosphere and isothermally reacted in a salt bath at temperatures ranging from 690℃ to 610℃.The specimens were polished with an automatic grinder polisher,then etched with 3% *** hardness indents were applied using a hardness tester with a Vickers hardness *** polishing,etching and hardness indenting a series of digital optical micrographs were *** digital image was aligned and processed by Scion Image and Adobe Photoshop,*** images were transferred into a volume data set by ImgToVol,and then was visualized using AVS software. 3D reconstruction shows that intragranular ferrite are formed on *** morphology of intragranular ferrite changes with *** higher temperatures(low undercooling) intragranular ferrite appeared to be an equiaxed *** lower temperatures(high undercooling) intragranular ferrite appeared to be a plate or a lath.

关键词： Steels Microstructure Intragranualr Ferrite Three-dimensional morphology

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Neural Regeneration Research 2025年第2期20卷 481-482页

作者： Khaled Alok Timothy g.White Chunyan li Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trigeminal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading depolarizations(CSDs)accompanied by compromised cerebral perfusion may exacerbate neurological *** pharmacological interventions have demonstrated initial potential in addressing CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerging bioelectronic methodologies for addressing CSDs,particularly emphasizing TNS,and to underscore TNS’s capacity to enhance neurovascular coupling and cerebral perfusion.

关键词： cerebral perfusion electronic

Interpretable Machine Learning Method for Compressive Strength Prediction and Analysis of Pure Fly Ash-based geopolymer Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 65-78页

作者： SHI Yuqiong li Jingyi zHANg Yang li li Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F Uni-versityYangling 712100China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China Chongqing Key Laboratory of Public Big Data Security Technology Chongqing 401420China Chongqing College of Mobile Communication Chongqing 401520China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityKowloonHung HomHong KongChina

In order to study the characteristics of pure fly ash-based geopolymer concrete(PFgC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive *** this study,505 groups of data were collected,and a new database of compressive strength of PFgC was *** order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative *** five machine learning models all showed good compressive strength prediction performance on *** them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,*** R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,*** two models have high prediction accuracy and outstanding generalization *** order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 *** 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide *** temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFgC than ordinary Portland cement *** importance of curing conditions of PFgC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.

关键词： machine learning pure fly ash geopolymer compressive strength feature perception

Manufacture the conducting polymer with light

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Science China Chemistry 2025年第1期68卷 8-9页

作者： Yang li Tianyu li Yan Ji Baoguang liu College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology) Nanjing University of Posts & Telecommunications

Poly(3,4-ethylenedioxythiophene) (PEDOT), heralded as the “king” of conducting polymers, is esteemed in bioelectronics for its mixed electronic and ionic conductivity, mechanical properties compatible with biological tissues, tunable healing ability and stability in diverse environments [1]. Based on additive manufacturing of three-dimensional structures,PEDOT realizes the implementation in the efficient production of flexible bioelectronics, the construction of intricate electrode-neural implantations, and the development of smart brain-computer-interfaces [2].

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A Wind Tunnel Experimental Study on the Wake Characteristics of a Horizontal Axis Wind Turbine

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Journal of Thermal Science 2025年第1期34卷 145-158页

作者： gUO Xingduo li Yinran li Rennian MA Yulong WEI Kui College of Energy and Power Engineering Lanzhou University of Technology Key Laboratory of Fluid Machinery and Systems gansu Provincial Technology Centre for Wind Turbines

The characteristics of wind turbine wakes are influenced by multiple factors,including the atmospheric boundary layer(ABL) wind and wind turbine operating conditions(e.g.,tip speed ratio and yaw angle).In this study,two types of ABL winds with different velocity gradients and turbulence intensities are generated in a wind tunnel through configurations of spires,baffles,and various numbers of roughness elements.A wind turbine with a rotor diameter of 0.8 m and a hub height of 0.6 m is tested under varying tip speed ratios,yaw angles,and ABL wind *** results indicate that the streamwise velocity deficit in the near-wake region becomes more pronounced with an increase in the tip speed ratio,while the far-wake velocity deficit remains largely unaffected by changes in the tip speed *** the yaw angle increases,the wake deflection becomes more prominent and the wake narrows;the offset of the wake center at various downstream positions grows linearly,reaching a maximum value of approximately half the rotor ***,the turbulence level and influence range in the wake region are reduced when the turbine is *** ABL wind conditions,high turbulence intensity in the incoming flow accelerates wake recovery,and the Reynolds stress at different lateral positions tends to become consistent with increasing longitudinal ***,turbulence has a significant impact on the meandering characteristics of the wind turbine wake,with greater fluctuations in the wake center observed under higher turbulence ***,this study provides insights that could inform the optimal operation of wind farms.

关键词： horizontal axis wind turbine turbulence wind tunnel experiment wind turbine wake

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He li li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(gWs) within the standard model of particle physics. If these background gWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes