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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu zhenyu Sun Weichen zheng Liangwei z.ang Yanling xue Wenning Liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

Construction of 3D porous Cu_(1.81)S/nitrogen-doped carbon frameworks for ultrafast and long-cycle life sodium-ion storage

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 191-200页

作者： Chen Chen Hongyu xue Qilin Hu Mengfan Wang Pan Shang ziyan Liu Tao Peng Deyang z.ang Yongsong Luo Key Laboratory of Microelectronics and Energy of Henan Province Henan Joint International Research Laboratory of New Energy Storage TechnologyCollege of Physics and Electronic EngineeringXinyang Normal UniversityXinyang 464000China School of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific ***,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs ***,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for ***,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 *** work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.

关键词： copper sulfide nanoparticles porous carbon framework fast charging long-cycle performance sodium-ion full batteries

A transfer learning enhanced physics-informed neural network for parameter identification in soft materials

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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1685-1704页

作者： Jing’ang zHU Yiheng xue zishun LIU International Center for Applied Mechanics State Key Laboratory for Strength and Vibration of Mechanical StructuresSchool of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China

Soft materials,with the sensitivity to various external stimuli,exhibit high flexibility and *** prediction of their mechanical behaviors requires advanced hyperelastic constitutive models incorporating multiple ***,identifying multiple parameters under complex deformations remains a challenge,especially with limited observed *** this study,we develop a physics-informed neural network(PINN)framework to identify material parameters and predict mechanical fields,focusing on compressible Neo-Hookean materials and *** improve accuracy,we utilize scaling techniques to normalize network outputs and material *** framework effectively solves forward and inverse problems,extrapolating continuous mechanical fields from sparse boundary data and identifying unknown mechanical *** explore different approaches for imposing boundary conditions(BCs)to assess their impacts on *** enhance efficiency and generalization,we propose a transfer learning enhanced PINN(TL-PINN),allowing pre-trained networks to quickly adapt to new *** TL-PINN significantly reduces computational costs while maintaining *** work holds promise in addressing practical challenges in soft material science,and provides insights into soft material mechanics with state-of-the-art experimental methods.

关键词： soft material parameter identification physics-informed neural network(PINN) transfer learning inverse problem

Distinguishing Oil and Water Layers in a Porous Cracked Medium by Interpreting Acoustic Logging Data on the Basis of Hudson Theory

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Journal of Earth Science 2017年第3期28卷 500-506页

作者： xue'ang z.ang zhuwen Wang zhichao Yang Engineering Research Center of Nuclear Technology Application Ministry of EducationEast China University of TechnologyNanchang 330013China Faculty of GeoExploration Science and Technology Jilin UniversityChangchun 130000China School of Geophysics and Measurement-Control Technology East China University of TechnologyNanchang 330013China

During surveys, water layers may interfere with the detection of oil layers. In order to distinguish between oil and water layers in a porous cracked medium, research on the properties of cracks and oil and water layers and their relation to acoustic logging rules is essential. On the basis of Hudson＇s crack theory, we simulated oil and water layers in crack-porous medium with different crack parameters corresponding to the well-field response. We found that in a cracked medium with high crack angle or low number density of cracks, compressional and shear wave velocities are sensitive to crack characteristics; further, these velocities are more sensitive to crack characteristics when the waves propagate through the water layer than when they propagate through the oil layer. Compressional and shear wave velocities increase with an increase in crack angle： in the water layer, the increase is approximately linear. On comparing the full waveforms observed in the oil and water layers, we find that the amplitudes of most waves are higher in the water layer. Among the considered waves, the Stoneley wave suffers maximum amplitude attenuation in the oil layer. The maximum excitation intensity for oil layer is greater than that for the water layer. These results can guide further cracked media logging field exploration work.

关键词： crack acoustic logging Hudson theory numerical simulation reservoir

Experimental Study on the Effect of Increased Downstroke Duration for an FWAV with Morphing-coupled Wing Flapping Configuration

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Journal of Bionic Engineering 2024年第1期21卷 192-208页

作者： ang Chen Bifeng Song zhiheWang Kang Liu Dong xue Xiaojun Yang School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China Harbin Institute of Technology Shenzhen 518055China

This paper is based on a previously developed bio-inspired Flapping Wing Aerial Vehicle(FWAV),RoboFalcon,which can fly with a morphing-coupled flapping *** this paper,a simple flapping stroke control system based on Hall effect sensors is designed and applied,which is capable of assigning different up-and down-stroke speeds for the RoboFalcon platform to achieve an adjustable downstroke *** aerodynamic and power characteristics of the morphing-coupled flapping pattern and the conventional flapping pattern with varying downstroke ratios are measured through a wind tunnel experiment,and the corresponding aerodynamic models are developed and analyzed by the nonlinear least squares *** relatively low power consumption of the slow-downstroke mode of this vehicle is verified through outdoor flight *** results of wind tunnel experiments and flight tests indicate that increased downstroke duration can improve aerodynamic and power performance for the RoboFalcon platform.

关键词： Flapping wing aerial vehicle(FWAV) Downstroke ratio Bio-inspired design Morphing-coupled flapping

Ethylene Response Factor TERF1 Enhances Glucose Sensitivity in Tobacco through Activating the Expression of Sugar-related Genes

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Journal of Integrative Plant Biology 2009年第2期51卷 184-193页

作者： ang Li zhijin z.ang xue-Chen Wang Rongfeng Huang National Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University Beijing 100094 China Biotechnology Research Institute the Chinese Academy of Agricultural Sciences Beijing 100081 China National Key Facility of Crop Gene Resources and Genetic Improvement Beijing 100081 China National Center for Plant Gene Research (Beijing) Beijing 100081 China

Ethylene response factor （ERF） proteins are important plant-specific transcription factors. Increasing evidence shows that ERF proteins regulate plant pathogen resistance, abiotic stress response and plant development through interaction with different stress responsive pathways. Previously, we revealed that overexpression of TERF1 in tobacco activates a cluster gene expression through interacting with GCC box and dehydration responsive element （DRE）, resulting in enhanced sensitivity to abscisic acid （ABA） and tolerance to drought, and dark green leaves of mature plants, indicating that TERF1 participates in the integration of ethylene and osmotic responses. Here we further report that overexpression of TERF1 confers sugar response in tobacco. Analysis of the novel isolated tomato TERF1 promoter provides information indicating that there are many cis-acting elements, including sugar responsive elements （SURE） and W box, suggesting that TERF1 might be sugar inducible. This prediction is confirmed by results of reverse transcription-polymerase chain reaction amplification, indicating that transcripts of TERF1 are accumulated in tomato seedlings after application of glucose. Further investigation indicates that the expression of TERF1 in tobacco enhances sensitivity to glucose during seed germination, root and seedling development, showing a decrease of the fresh weight and root elongation under glucose treatment. Detailed investigations provide evidence that TERF1 interacts with the sugar responsive cis-acting element SURE and activates the expression of sugar response genes, establishing the transcriptional regulation of TERF1 in sugar response. Therefore, our results deepen our understanding of the glucose response mediated by the ERF protein TERF1 in tobacco.

关键词： Ethylene response factor protein TERF1 glucose sugar responsive gene tobacco

Precise large deviations for sums of random vectors in a multidimensional size-dependent renewal risk model

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Applied Mathematics(A Journal of Chinese Universities) 2018年第4期33卷 491-502页

作者： SHEN Xin-mei FU Ke-ang zHONG xue-ting School of Mathematical Sciences Dalian University of Technology School of Statistics and Mathematics Zhejiang Gongshang University

Consider a multidimensional renewal risk model, in which the claim sizes {Xk, k ≥1} form a sequence of independent and identically distributed random vectors with nonnegative components that are allowed to be dependent on each other. The univariate marginal distributions of these vectors have consistently varying tails and finite means. Suppose that the claim sizes and inter-arrival times correspondingly form a sequence of independent and identically distributed random pairs, with each pair obeying a dependence structure. A precise large deviation for the multidimensional renewal risk model is obtained.

关键词： Precise large deviation Size-dependent Consistent variation Multidimensional risk model Renewal counting process

Analyzing the Flavor Compounds in Chinese Traditional Fermented Shrimp Pastes by HS-SPME-GC/MS and Electronic Nose

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Journal of Ocean University of China 2017年第2期16卷 311-318页

作者： FAN Yan YIN Li-ang xue Yong LI zhaojie HOU Hu xue Changhu College of Food Science and Engineering Ocean University of ChinaQingdao 266003P.R.China

Shrimp paste is a type of condiments with high nutritional ***,the flavors of shrimp paste,particularly the non-uniformity flavors,have limited its application in food *** order to identify the characteristic flavor compounds in Chinese traditional shrimp pastes,five kinds of typical commercial products were evaluated in this *** differences in the volatile composition of the five products were *** phase micro-extraction method was employed to extract the volatile ***-MS and electronic nose were applied to identify the compounds,and the data were analyzed using principal component analysis(PCA).A total of 62 volatile compounds were identified,including 8 alcohols,7 aldehydes,3 ketones,7 ethers,7 acids,3 esters,6 hydrocarbons,12 pyrazines,2 phenols,and 7 other *** typical volatile compounds contributing to the flavor of shrimp paste were found as follows:dimethyl disulfide,dimethyl tetrasulfide,dimethyl trisulfide,2,3,5-trimethyl-6-ethyl pyrazine,ethyl-2,5-dimethyl-pyrazine,phenol and *** acid,butanoic acid,furans,and 2-hydroxy-3-pentanone caused unpleasant odors,such as pungent and rancid *** component analysis showed that the content of volatile compounds varied depending on the processing conditions and shrimp *** results indicated that the combinations of multiple analysis and identification methods could make up the limitations of a single method,enhance the accuracy of identification,and provide useful information for sensory research and product development.

关键词： volatile flavor compounds GC-MS electronic nose sensory analysis

Effects of dynamical spanwise retraction and stretch on flapping-wing forward flights

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Chinese Journal of Aeronautics 2024年第4期37卷 181-202页

作者： Kang LIU Bifeng SONG ang CHEN zhihe Wang Dong xue Wenqing Yang School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Intelligent Aircraft Research Center Chengdu Technological UniversityChengdu 610031China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China Harbin Institute of Technology Shenzhen 518055China

Birds and bats retract and stretch their wings dynamically during each flap in level flights, implying intriguing mechanisms for the aerodynamic performance improvement of flapping wings. A numerical investigation into the aerodynamic effects of such bio-inspired concept in forward flights has been performed based on a three-dimensional wing in plunging motion and a twosection wing in flapping motion. The currently considered Reynolds number and Strouhal number are Re=1.5×10^(5) and St=0.3, respectively. During the research, the mean angle of attack is varied in relatively wide ranges to achieve lift-thrust interconversion for the wings. The conclusive results show that dynamical spanwise retraction and stretch has induced three absolutely desirable scenarios for the oscillating wings in forward flights, namely producing more lift and consuming less power for a given thrust generation, producing more thrust and consuming less power for a given lift generation, and producing more lift and more thrust while consuming less power. Furthermore,the morphing wings have alleviated periodical aerodynamic load fluctuations compared with the non-morphing baseline. The mechanism of the aerodynamic effects of the bionic morphing mode is analyzed with the aid of field visualization. The current article is the first to reveal the absolute advantages of the bionic spanwise morphing. Hopefully, it may help comprehend the behaviors of natural fliers and provide inspirations for performance enhancement of micro artificial flappingwing vehicles.

关键词： Flapping wing Morphing wing Bionic Aerodynamics Vortex Flight

PREPARATION OF POLY(METHYL METHACRYLATE)/LAYERED DOUBLE HYDROXIDES NANOCOMPOSITES via in situ SOLUTION POLYMERIzATION

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Chinese Journal of Polymer Science 2007年第6期25卷 573-579页

作者： ang-ran Wang Yong-zhong Bao zhi-xue Weng zhi-ming Huang State Key Laboratory of Chemical Engineering Zhejiang University Hangzhou 310027 China

An exfoliated layered double hydroxides/poly（methyl methacrylate）（LDHs/PMMA） nanocomposite was prepared by in situ solution polymerization of methyl methacrylate （MMA） in the presence of 4-vinylbenzenesulfonate intercalated LDHs（MgAl-VBS LDHs）. MgAl-VBS LDHs was prepared by the ion exchange method, and the structure and composition of the MgAl-VBS LDHs were determined by X-ray diffraction （XRD）, infrared spectroscopy and elemental analysis. XRD and transmission electron microscopy （TEM） were employed to examine the structure of LDHs/PMMA nanocomposite. It was indicated that the LDHs layers were well exfoliated and dispersed in the PMMA matrix. The grafting of PMMA onto LDHs was confirmed by the extraction result and the weight fraction of grafted PMMA increased as the weight fraction of LDHs in the nanocomposites increased.

关键词： Nanocomposite Poly(methyl methacrylate) Layered double hydroxides.