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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu lin He lin-Sen ye Xiao-Feng Yang Jia-Jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Path-Dependent Progressive Failure Analysis for 3D-Printed Continuous Carbon Fibre Reinforced Composites

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 84-93页

作者： Yuan Chen lin ye School of System Design and Intelligent Manufacturing(SDIM) Southern University of Science and TechnologyShenzhen 518055China Shenzhen Key Laboratory of Intelligent Manufacturing for Continuous Carbon Fibre Reinforced Composites Southern University of Science and TechnologyShenzhen 518055China

In order to predict the damage behaviours of 3D-printed continuous carbon fibre(CCF)reinforced composites,when additional short carbon fibre(SCF)composite components are employed for continuous printing or special functionality,a novel path-dependent progressive failure(PDPF)numerical approach is ***,a progressive failure model using Hashin failure criteria with continuum damage mechanics to account for the damage initiation and evaluation of 3D-printed CCF reinforced polyamide(PA)composites is developed,based on actual fibre placement trajectories with physical measurements of 3D-printed CCF/PA ***,an elastic-plastic model is employed to predict the plastic damage behaviours of SCF/PA ***,the accuracy of the PDPF model was validated so as to study 3D-printed CCF/PA composites with either negative Poisson's ratio or high *** results demonstrate that the proposed PDPF model can achieve higher prediction accuracies in mechanical properties of these 3D-printed CCF/PA *** analyses show that the stress distribution is generally aggregated in the CCF areas along the fibre placement paths,and the shear damage and matrix tensile/compressive damage are the key damage *** study provides a new approach with valuable information for characterising complex 3D-printed continuous fibre-matrix composites with variable mechanical properties and multiple constituents.

关键词： 3D printing Continuous carbon fibre Modelling Energy absorption Negative Poisson's ratio

Investigations of Water Flow Behaviors Induced by Local Temperature Variations through a Single Rough Fracture for the Enhanced Geothermal Systems

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Journal of Thermal Science 2024年第3期33卷 1055-1064页

作者： LI Jiawei ye lin Department of Energy and Power Engineering Tsinghua UniversityBeijing100084China School of Power and Energy Northwestern Polytechnical UniversityXi’an710072China

In recent years,Enhanced Geothermal System(EGS)technologies have been applied to the geothermal resources production in the Hot Dry Rock(HDR).The core of EGS technologies is to adopt hydraulic fracturing in the reservoir to create a connected network of discrete fractures with the consideration of water as a working fluid for hydraulic fracturing and heat *** paper investigates the characteristics of water flow behaviors through a single rough fracture under different temperature and pressure conditions.A single fracture model with rough fracture surfaces is constructed and then characterized,and influences of the anisotropic factor on the average tortuosity and frictional resistance coefficient of water flow through a single fracture with rough surfaces have been compared and *** consideration of other impacting factors(temperature,pressure,fracture roughness),the impact of mass flow rate has also been *** simulation results present that changes of average tortuosity for water flow through a single rough facture are mainly affected by *** can be observed that higher temperature leads to larger average tortuosity but the frictional resistance coefficient shows an opposite *** for pressure conditions,it is found that effects of pressure on average tortuosity and frictional resistance coefficient is very small,which can be neglected under high pressure ***,the average tortuosity shows a progressively linear relationship with the mass flow *** the contrary,the frictional resistance coefficient has a negative relationship with the mass flow *** is revealed that when the mass flow rate reaches a critical point,the influences of temperature on the frictional resistance coefficient will be *** of single rough fractures with different anisotropic factors show that values of average tortuosity and frictional resistance coefficient have positive relationships with the increase

关键词： single rough fracture tortuosity frictional resistance enhanced geothermal system

我国农产品流通效率时空演变、地区差异与收敛性

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经济问题 2025年第1期 100-112页

作者：高国生叶林祥支海兵南京财经大学粮食和物资学院江苏南京210003 南京审计大学金审学院管理学院江苏南京210023 南京财经大学经济学院江苏南京210003

农产品流通效率事关我国粮食安全和全国统一大市场的建成。运用熵值法测度了2011—2022年我国31个省级行政区的农产品流通效率,并使用Moran’s I、Kernel核密度估计、Markov链、Dagum基尼系数和β收敛模型分别分析了我国农产品流通效率... 详细信息

农产品流通效率事关我国粮食安全和全国统一大市场的建成。运用熵值法测度了2011—2022年我国31个省级行政区的农产品流通效率,并使用Moran’s I、Kernel核密度估计、Markov链、Dagum基尼系数和β收敛模型分别分析了我国农产品流通效率的时空演变、地区差异与收敛性情况。结果显示:研究期内我国农产品流通效率存在显著正向空间相关性,“高—高”集聚和“低—低”集聚特征明显;核密度曲线宽度变大呈现右拖尾和高度差明显的双峰形态,表明农产品流通效率逐渐提升,地区内部存在极化趋势;相邻省区市空间滞后水平对本省区市农产品流通效率维持原有状态或向更高水平发展均有较大影响;地区间差异是造成农产品流通效率总体差异显著的主要原因;农产品流通效率存在显著绝对β收敛和条件β收敛。据此,对如何提高农产品流通效率和缩小地区间差距提出了相关政策建议。

关键词：农产品流通效率时空演变空间分布地区差异

Functionalized interleaf technology in carbon-fibre-reinforced composites for aircraft applications

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National Science Review 2014年第1期1卷 7-8页

作者： lin ye School of Aerospace Mechanical and Mechatronic Engineering and Centre for Advanced Materials Technology University of Sydney

At the recent 19th International Conference of Composite Materials(ICCM-19),in Montreal,Professor Xiaosu Yi from the Beijing Institute of Aeronautical Materials,Aviation Industry Corporation of China,gave a plenary lecture on‘How to Make the Structural Composites Multi-functional’.His lecture highlighted the recent developments from his research team in functionalized interleaf technology(FIT).heir work

关键词： Ag

Investigation of the overconsolidation and structural behavior of Shanghai clays by element testing and constitutive modeling

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Underground Space 2016年第1期1卷 62-77页

作者： Guan-lin ye Bin ye Department of Civil Engineering and State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

The mechanical properties and constitutive modeling of Shanghai clays are very important for numerical analysis on geotechnical engineering in Shanghai,where continuous layers of soft clays run 30-40 m *** clays are divided into 5 major layers.A series of laboratory tests are carried out to investigate their mechanical *** top and bottom layers are overconsolidated hard clays,and the middle layers are normally consolidated or lightly overconsolidated sensitive marine clays.A constitutive model,which can describe the overconsolidation and structure of soils using only 8 parameters,is modified to simulate the test results.A rational procedure to determine the values of the material parameters and initial conditions is also *** model is able to effectively reproduce both one-dimensional(1D)consolidation and drained/undrained triaxial test results of Shanghai clays,with one set of parameters for each *** element testing and constitutive modeling,two findings are ***,the decay rates of overconsolidation are smaller in overconsolidated layers than in normally consolidated ***,the natural microstructure of layer 4 is relatively stable,that is,a large degree of structure is still maintained in the specimen even after 1D consolidation and drained triaxial *** modified model and obtained parameter values can be used for numerical analysis of geotechnical projects in Shanghai.

关键词： Shanghai clays Laboratory tests Constitutive model Overconsolidation Structure

Optimal mother wavelet-based Lamb wave analyses and damage detection for composite structures

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仪器仪表学报 2007年第10期28卷 1729-1735页

作者： Li Fucai Meng Guang ye lin State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China School of Aerospace Mechanical ＆ Mechatronic Engineering The University of Sydney NSW 2006 Australia

With the purpose of on-line structural health monitoring,a transducer network was embedded into compos- ite structure to minimize the influence of *** intrinsic dispersion characteristic of Lamb wave makes the wavelet transform an effective signal processing method for guided *** get high precision in feature extrac- tion,an information entropy-based optimal mother wavelet selection approach was proposed,which was used to choose the most appropriate basis function for particular Lamb wave *** using the embedded sensor network and extracting time-of-flight,delamination in the composite laminate was identified and *** results demon- strate the effectiveness of the proposed methods.

关键词：拉姆波损失探测内传感器信息熵最优小波基

Nuclear clustering in light neutron-rich nuclei

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Nuclear Science and Techniques 2018年第12期29卷 112-127页

作者： Yang Liu Yan-lin ye School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University

Clustering is a general phenomenon observed in light nuclei, especially in neutron-rich nuclei in which molecular configurations can be formed with various combinations of valence neutrons. Thus far, many theoretical models have been developed to describe nuclear clustering phenomena. These models are outlined in this review article, with an emphasis on their basic formulations and physical ingredients. In addition, various experimental tools, such as inelastic excitation and decay, transfer reactions, and resonant scattering reactions, have been applied to investigate the cluster structures inside the nucleus. Each tool possesses certain advantages and favorable applications, which are also described. In the case of neutron-rich nuclei, cluster structures may be configured as molecular states that form rotational bands with an extremely large moment of inertia and generate relatively large cluster decay width. The major experimental criteria for the identification of cluster formation are discussed herein.

关键词：轻原子核中子聚类转移反应簇结构物理成分应用程序试验性

Expression and function of leptin and its receptor in mouse mammary gland

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Science China(Life Sciences) 2007年第5期50卷 669-675页

作者： lin ye LI QingZhang Key Laboratory of Dairy Science of Ministry of Education Northeast Agricultural University Harbin 150030 China Key Laboratory of Dairy Science of Ministry of Education Northeast Agricultural University Harbin 150030 China

Leptin is an autocrine and paracrine factor which affects the development of duct, formation of gland alveolus, expression of milk protein gene and onset involution of mammary gland. In order to know the function and mechanism of leptin in mammary gland, the protein expression and localization of leptin and its long form receptor (OB-Rb) were detected by a confocal laser scanning microscope. To study the impacts of leptin on mammary gland and leptin signal transduction pathway in pregnancy-, lacta-tion-and involution-stage mammary gland, explants were cultured and Western blotting was used. The results showed that in the whole development cycle of mammary gland, the expression of leptin and OB-Rb was in positive correlation. In virgin the leptin expression was the highest and then decreased in pregnancy. In lactation the expression of leptin was low and upgraded in involution, and recovered to the original level about virgin on involution 13 d. The localization of leptin and OB-Rb revealed that leptin induced the expression of OB-Rb specifically and controlled the development and physiological function of the mammary gland by binding to OB-Rb. In pregnancy stage, leptin stimulated proliferation and differentiation of ductal epithelial cells by JAK-MAPK signal pathway. In lactation, leptin induced gene expression of β-casein by JAK-STAT5 signal pathway, and in involution leptin induced mammary epithelial cell apoptosis and mammary gland restitution by JAK-STAT3 signal pathway.

关键词： mammary gland, leptin, OB-Rb, expression, signal transduction

Clustering in nuclei:progress and perspectives

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Nuclear Science and Techniques 2024年第12期35卷 343-375页

作者： Kang Wei Yan‑lin ye Zai‑Hong Yang School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China

Nucleus is essentially composed of protons and neutrons,which are commonly known as ***,some of nucleons may group together and exhibit collective behavior inside a *** clustering efects have been known since the early stages of nuclear physics because of the observation and description ofα-cluster decay from many heavy *** studies demonstrated that cluster structures exist in many nuclear systems,especially in weakly bound or excited states,and are complementary to the shell-like *** this review article,we provide a brief historical recall of the feld,and follow it with a conceptual and logical description of the major theoretical models that have been frequently applied in the literature to describe nuclear *** methods and progress are outlined,recent outcomes are emphasized,and perspectives relevant to future studies of heavy neutron-rich systems are discussed.

关键词： Nuclear matter Cluster structure Wave-packet presentation Molecular bond Condensation confguration