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Effects of Ni-Cr Based Alloys on the Fiber MetallurgyCharacteristics of Short Cast Iron Fibers

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Journal of Materials Science & Technology 1995年第4期11卷 287-290页

作者： HE, JL YU, DL ZHANG, M TIAN, YG CHEN, SZ li, dc Yanshan Univ Qinhuangdao China

The liquid sintering characteristics have been studied in the sintered compacts of short cast iron fibers added with Ni-Cr based alloy powder at the sintering temperature of 1100 degrees C. With the increase of Ni-Cr based alloy content, the microstructure of sintered compact of short cast iron fibers transformed from pearlite + ferrite to martensite + austenite, meanwhile volume expansion appeared in the sintered compact, leading to more pores. The proper addition of P-Fe powder could restrain the expansion of the sintered compact and increase the strength and hardness of the sintered compact.

关键词： Synthetic fibers

Characterization of C-N Thin Films Prepared by Ion Beam Sputtering

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Journal of Materials Science & Technology 1996年第4期12卷 312-314页

作者： Tian, YJ Ren, XJ Yu, DL He, JL Chen, SZ li, dc Yu, RC Zhang, M Wang, WK CHINESE ACAD SCI INST PHYSBEIJING 100080PEOPLES R CHINA

C-N thin films have been prepared by ion beam sputtering using pure N-2 as discharge gas. The ratio N/C of the films measured by Auger spectrum is 20% on an average. The results of X-ray diffraction and transmission electron microscopy show that beta-C3N4. phase exists in the films. X-ray photoelectron spectroscopy shows that nitrogen is mostly combined with carbon with triple (C=N) and double (C=N) bonds. The IR absorption shows an absorption bond near 2185 cm(-1) assigned to the C=N, no trace of C-C bond was observed.

关键词： Thin films

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

Deciphering the role of mtH2O2 in hepatic ischemia-reperfusion injury mechanisms with low-background super-resolution fluorogenic probe

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Science China Chemistry 2025年第1期68卷 297-307页

作者： Bin Fang limin Wang Haoqin li Jiaxin Zhang Yang Ding Pan Pan li Bo Peng Hua Bai lin li Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials &Engineering Northwestern Polytechnical University Institute of Flexible Electronics (IFE Future Technologies) Xiamen University

Hepatic ischemia-reperfusion injury（HIRI） is characterized by mitochondrial dysfunction and oxidative stress. Monitoring mitochondrial hydrogen peroxide（mtH2O2） levels in real-time through super-resolution imaging is crucial for elucidating its distribution in live cells and its mechanism of action during HIRI. However, low-background fluorogenic probes have been overlooked in the context of super-resolution imaging. In this study, we developed a low-background fluorogenic probe（MitoWG） with the potential for super-resolution morphology-correlated mitochondrial identification to track the fluctuates of mtH2O2in HIRI. Activation of the desirable fluorescence properties of the probe by mtH2O2was confirmed using structural illumination microscopy（SIM）, enabling high-quality mitochondrial imaging with exceptional specificity and *** in mtH2O2levels were successfully observed in both cellular and rat models of HIRI. Furthermore, we associated the decline in mitochondrial redox homeostasis with accelerated mtH2O2production during HIRI, which triggered mitophagy deficiency and led to cell death. In conclusion, Mito-WG possesses excellent photophysical and low-background properties for SIM imaging, making it a promising tool for mtH2O2tracking in HIRI research and clinical diagnosis.

关键词： hepatic ischemia-reperfusion injury low-background mtH2O2-activatable super-resolution imaging fluorogenic probe

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng li Meifeng Cai Shengjun Miao Yuan li Yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

Design of a cationic accelerator enabling ultrafast ion diffusion kinetics in aqueous zinc-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 377-384页

作者： Yawei Xiao Qianqian Gu Haoyu li Mengyao li Yude Wang National Center for International Research on Photoelectric and Energy Materials School of Materials and Energy Yunnan University Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources School of Chemistry and Chemical Engineering Hainan University College of Chemical Engineering Fuzhou University Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon Technologies Yunnan University

Aqueous zinc-ion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion *** address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn2+diffusion *** employing electrodeposition to coat MoS2on the surface of BaV6O16·3H2O nanowires,the directional built-in electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn2+diffusion into the active *** optimized Zn2+diffusion coefficient in CC@BaV-6O16·3H2O@MoS2(7.5×10～8cm2s-1) surpasses that of most reported V-based ***,MoS2serving as a cathodic armor extends the cycling life of the Zn-CC@BaV6O16·3H2O@MoS2full batteries to over 10000 *** work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices.

关键词： Zinc alloys