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Design and fabrication of lightweight AlCrFeNiTi_(x) compositionally complex alloys with exceptional specific strength

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Rare Metals 2024年第7期43卷 3314-3328页

作者： Jun-zhi Li Wei-Zong Bao Jie Chen Bo-Hua Yu Kun zuo Tian Gao Ze-Yun Cai Guo-qiang Xie School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

This study focuses on compositionally complex alloys(CCAs),aiming to achieve a balance between high strength and low density for new energy and aerospace *** composition of AlCrFeNiTi_(x) CCAs is strategically guided by employing density functional theory and the theoretical design of thermodynamic *** CCAs,particularly AlCrFeNiTi_(0.25) alloy,demonstrate remarkable specific yield strength(1640.8 MPa) and 22.7% maximum *** incorporation of Ti facilitates the formation of lightweight and high-strength L2_(1)phase,contributing to the overall high specific *** effects of grain boundary strengthening,solid solution strengthening,Orowan strengthening and Peierls flow stress further enhance *** exploration of micros tructural changes during fracture reveals the role of ordered phases in suppressing crack propagation and absorbing energy within disordered phases,thereby improving the toughness and fracture resistance of *** methods and discoveries establish a robust foundation for advancing the development of novel lightweight CCAs.

关键词： Lightweight Compositionally complex alloys Specific yield strength

A comprehensive review on microchannel heat sinks for electronics cooling

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International Journal of Extreme Manufacturing 2024年第2期6卷 133-162页

作者： zhi-qiang Yu Mo-Tong Li Bing-Yang Cao Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084People’s Republic of China

The heat generation of electronic devices is increasing dramatically,which causes a serious bottleneck in the thermal management of electronics,and overheating will result in performance deterioration and even device *** the development of micro-machining technologies,the microchannel heat sink(MCHS)has become one of the best ways to remove the considerable amount of heat generated by high-power *** has the advantages of large specific surface area,small size,coolant saving and high heat transfer *** paper comprehensively takes an overview of the research progress in MCHSs and generalizes the hotspots and bottlenecks of this *** heat transfer mechanisms and performances of different channel structures,coolants,channel materials and some other influencing factors are ***,this paper classifies the heat transfer enhancement technology and reviews the related studies on both the single-phase and phase-change flow and heat *** comprehensive review is expected to provide a theoretical reference and technical guidance for further research and application of MCHSs in the future.

关键词： microchannel heat sink thermal management of electronics microscale heat transfer heat transfer enhancement

Precise Asymptotics in Limit Theorems for a Supercritical Branching Process with Immigration in a Random Environment

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1850-1874页

作者： Chun Mao HUANG Rui ZHANG zhi qiang GAO Department of Mathematics Harbin Institute of Technology(Weihai)Weihai 264209P.R.China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China

Let(Zn)be a supercritical branching process with immigration in an independent and identically distributed random *** necessary moment conditions,we show the exact convergence rate in the central limit theorem on log Zn and establish the corresponding local limit theorem by using the moments of the natural submartingale and the convergence rates of its *** similar approach and with the help of a change of measure,we also present the so-called integrolocal theorem and integral large deviation theorem to characterize the precise asymptotics of the upper large deviations.

关键词： Branching process with immigration random environment central limit theorem large deviation

Research progress on micro-force measurement of a hydrate particle system

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Petroleum Science 2024年第4期21卷 2169-2183页

作者： qiang Luo Wei Li zhi-Hui Liu Feng Wang zhi-Chao Liu Fu-Long Ning Faculty of Engineering China University of Geosciences (Wuhan) Suzhou Laboratory

It remains a great challenge to understand the hydrates involved in phenomena in practical oil and gas systems. The adhesion forces between hydrate particles, between hydrate particles and pipe walls, and between hydrate particles and reservoir particles are essential factors that control the behaviors of clathrate hydrates in different applications. In this review, we summarize the typical micro-force measurement apparatus and methods utilized to study hydrate particle systems. In addition, the adhesion test results, the related understandings, and the applied numerical calculation models are systematically discussed.

关键词： Clathrate hydrates Hydrate particle Micro-force measurements Adhesion Interactions

Transcriptome-based analysis of key signaling pathways affecting the formation of primordial germ cell in chickens

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Journal of Integrative Agriculture 2024年第5期23卷 1644-1657页

作者： Ying Ding Qiong zhi Qisheng zuo Kai Jin Wei Han Bichun Li Key Laboratory of Animal Genetics Breeding and Molecular Design of Jiangsu ProvinceCollege of Animal Science and TechnologyYangzhou UniversityYangzhou 225009China Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China Yangzhou UniversityYangzhou225009China Poultry Research Institute Chinese Academy of Agricultural Sciences/Jiangsu Institute of Poultry ScienceYangzhou 225009China

Bone morphogenetic protein 4(BMP4)can induce the formation of chicken primordial germ cells(PGCs)in vitro;however,its regulatory mechanism in poultry remains *** study aimed to use RNA-seq to analyze PGCs in chicken embryos and iPGCs induced by BMP4 in vitro,clarify the internal regulatory factors of PGCs,analyze the mechanism of the formation of PGCs,and lay a theoretical foundation for the further optimization of PGCs induction *** stem cells(ESCs),PGCs and iPGCs induced by BMP4 in vitro were *** transcriptional maps of the three cell types were studied using *** results showed 6,142 genes differentially expressed between PGCs and iPGCs,of which 2,728 were upregulated in iPGCs and 3,414 were downregulated in *** to that in ESCs,BMP4 was significantly upregulated in PGCs and *** results showed that both the TGF-βand Wnt signaling pathways were activated during the formation of PGCs in vitro and in vivo,and the activation was more significant during iPGCs induced by *** expression of Nodal,an inhibitory factor of TGF-βsignaling,was significantly decreased in PGCs and iPGCs,but was not expressed in iPGCs,which further supports our ***,the Lysosome and PI3K-AKT signaling pathways were significantly enriched in PGCs and iPGCs,***,transmission electron microscopy(TEM)results showed that the number of autolysosomes was significantly higher after the addition of BMP4,which is consistent with the KEGG ***,the number of PGCs was significantly reduced after ATG14 was interfered in vivo and in *** conclusion,this study screened out the key signaling pathways during the formation of PGCs,aiming to provide help for enriching the mechanism network regulating PGCs formation in chicken and laying a theoretical foundation for further improving the efficiency of inducing PGCs in vitro.

关键词： RNA-seq BMP4 PGCs ATG14 chicken

Effects of environment and genotype-by-environment interaction on phenotype of Rorippa elata(Brassicaceae),an endemic alpine plant in the Hengduan mountains

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Journal of Plant Ecology 2024年第4期17卷 42-55页

作者： zhi-qiang Du Yao-Wu Xing Ting-Shen Han CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Plant Diversity and Specialty Crops Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China

Global climate change poses a severe threat to mountain *** plasticity and local adaptation are two common strategies for alpine plant to cope with such *** may facilitate organismal adaptation to contrasting environments,depending on the influences of the environment or genotype or their interacted *** this study,we use an endemic alpine plant(Rorippa elata)in the Hengduan mountains(HDM)to unravel its phenotypic basis of adaptation strategy and evaluate the relative contributions of environment and genotype to its *** transplanted 37 genotypes of *** into two common gardens across low and high elevations(2800 vs.3800 m)during *** fitness-related traits were measured,including flowering probability and glucosinolates(GS)*** estimated the environmental or genotypic contributions to the phenotype and identified the main environmental *** results revealed that both environment and genotype-by-environment interactions contributed to the phenotypes of *** heterogeneity was identified as a key factor that explained 24%of the total phenotypic *** particular,genotypes of the northern HDM showed significantly higher plasticity in flowering probability than those of the southern ***,within the southern HDM,GS content indicated local adaptation to herbivory stresses for *** genotypes along *** conclusion,our results suggest that *** may have adapted to the alpine environment through species-level plasticity or regional-level local *** processes were shaped by either complex topography or interactions between genotype and mountain *** study provides empirical evidence on the adaptation of alpine plants.

关键词： alpine plant common garden genotype-by-environment Hengduan mountains local adaptation phenotypic plasticity

Intermittent disturbance mechanical behavior and fractional deterioration mechanical model of rock under complex true triaxial stress paths

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International Journal of Mining Science and Technology 2024年第1期34卷 117-136页

作者： zhi Zheng Hongyu Xu Kai Zhang Guangliang Feng qiang Zhang Yufei Zhao State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationCollege of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100080China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China

Mechanical excavation,blasting,adjacent rockburst and fracture slip that occur during mining excavation impose dynamic loads on the rock mass,leading to further fracture of damaged surrounding rock in three-dimensional high-stress and even causing ***,a novel complex true triaxial static-dynamic combined loading method reflecting underground excavation damage and then frequent intermittent disturbance failure is *** triaxial static compression and intermittent disturbance tests are carried out on *** effects of intermediate principal stress and amplitude on the strength characteristics,deformation characteristics,failure characteristics,and precursors of monzogabbro are analyzed,intermediate principal stress and amplitude increase monzogabbro strength and tensile fracture *** increases in microseismic parameters during rock loading can be precursors for intermittent rock *** on the experimental result,the new damage fractional elements and method with considering crack initiation stress and crack unstable stress as initiation and acceleration condition of intermittent disturbance irreversible deformation are proposed.A novel three-dimensional disturbance fractional deterioration model considering the intermediate principal stress effect and intermittent disturbance damage effect is established,and the model predicted results align well with the experimental *** sensitivity of stress states and model parameters is further explored,and the intermittent disturbance behaviors at different f are *** study provides valuable theoretical bases for the stability analysis of deep mining engineering under dynamic loads.

关键词： True triaxial static and disturbance test Mechanical properties Failure mechanism and precursor Intermittent disturbance effect Fractional mechanical model

Focal mechanics and disaster characteristics of the 2024 M 7.6 Noto Peninsula Earthquake,Japan

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Frontiers of Structural and Civil Engineering 2024年第9期18卷 1378-1387页

作者： Guang-qi CHEN Yan-qiang WU Ming-yao XIA zhi-yuan LI School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300131China Graduate School of Engineering Kyushu UniversityFukuoka 819-0395Japan The First Monitoring and Application Center China Earthquake AdministrationTianjin 300180China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China

On January 1,2024,a devastating M 7.6 earthquake struck the Noto Peninsula,Ishikawa Prefecture,Japan,resulting in significant casualties and property *** information from the first six days after the earthquake,this article analyzes the seismic source characteristics,disaster situation,and emergency response of this *** results show:1)The earthquake rupture was of the thrust type,with aftershock distribution showing a north-east-oriented belt-like feature of 150 km.2)Global Navigation Satellite System(GNSS)and Interferometric synthetic aperture radar(InSAR),observations detected significant westward to north-westward co-seismic displacement near the epicenter,with the maximum horizontal displacement reaching 1.2 m and the vertical uplift displacement reaching 4 m.A two-segment fault inversion model fits the observational data well.3)Near the epicenter,large Peak Ground Velocity(PGV)and Peak Ground Acceleration(PGA)were observed,with the maxima reaching 145 cm/s and 2681 gal,respectively,and the intensity reached the highest level 7 on the Japanese(Japan Meteorological Agency,JMA)intensity standard,which is higher than level 10 of the United States Geological Survey(USGS)Modified Mercalli Intensity(MMI)standard.4)The observation of the very rare multiple strong pulse-like ground motion(PLGM)waveform poses a topic worthy of research in the field of earthquake engineering.5)As of January 7,the earthquake had left 128 deaths and 560 injuries in Ishikawa Prefecture,with 1305 buildings completely or partially destroyed,and had triggered a chain of disasters including tsunamis,fires,slope failures,and road ***,this paper summarizes the emergency rescue,information dissemination,and other disaster response and management measures taken in response to this *** work provides a reference case for carrying out effective responses,and offers lessons for handling similar events in the future.

关键词： Noto Peninsula Earthquake earthquake rupture mechanism earthquake disaster emergency response pulse-like ground motion

Mechanical parameter evolutions and deterioration constitutive model for ductile-brittle failure of surrounding rock in high-stress underground engineering

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Underground Space 2024年第2期15卷 131-152页

作者： zhi Zheng Ronghua Li qiang Zhang Xiaohua Huang Wei Wang Shuling Huang State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationCollege of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang 110819China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources Yangtze River Scientific Research InstituteWuhan 430010China

The deep surrounding rock is usually in the true triaxial stress state,and previous constitutive models based on the understanding of uniaxial and conventional triaxial test results have difficulty characterizing the degradation and fracture process of rock ductile–brittle failure under true triaxial stress ***,this study conducted a series of true triaxial tests to obtain the understanding of the ductile–brittle behaviour of rock,and then combined the test results and the Mogi–Coulomb strength criterion,and proposed calculation methods for the elastic modulus E,cohesion c and internal friction angle u and the evolution functions of E,c and u of rock under true triaxial *** the decreasing of the minimum principal stress r3 or increasing of the intermediate principal stress r2,the marble post-peak stress drop rate gradually increases,the ductility gradually weakens,and the brittleness significantly *** calculation method and evolution function of rock E,c and u under true triaxial stress were proposed.E decreased at first and then tended to remain stable with the increasing of equivalent plastic strain increment dep.c and u slowly increased at first and then rapidly *** a method of parameter degradation rate to realize post-peak stress drop rate to reflect the ductile–brittle characteristics,a new three-dimensional ductile–brittle deterioration mechanical model(3DBDM)was *** proposed model can accurately characterize the influence of r2 and r3 on mechanical parameters,the ductile–brittle behaviour of rock under true triaxial stresses,and the asymmetric failure characteristics of surrounding rock after excavation of deep underground *** proposed model can be reduced to elastic–perfectly plastic,elastic–brittle,cohesion weakening friction strengthening(CWFS),Mohr–Coulomb,and Drucker–Prager models.

关键词： True triaxial stress Post-peak characteristics 3D deterioration model Elastic modulus evolution Cohesion and friction angle evolution