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Journal of Iron and Steel Research(International) 2024年第3期31卷 767-777页

作者： Hong-bin Dai jian miao jia-xin Lin School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

The welding arc,as a carrier for the conversion of electrical energy to thermal energy,has a direct impact on the quality of welding by its properties and *** the tungsten inert gas(TIG)welding process under the condition of Ar-He alternating gas supply,the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle,which has obvious arc change *** FLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply,and the arc temperature field,arc pressure,electric potential and current density distribution under the condition of alternating gas supply were *** with the real-time data of arc pressure measured by the water-cooled copper plate with holes,it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar-He alternating gas *** unique dynamic TIG arc acts on the 5A06 aluminum alloy weld,causing the molten pool to stir,resulting in uniform microstructure and grain refinement at the weld,and thereby improving the mechanical properties of the welded joint.

关键词： Alternating gas supply Grain refinement Numerical simulation Tungsten argon arc morphology Microstructure Mechanical property

Origin and evolution of false brinelling and fretting corrosion under rolling conditions

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Friction 2024年第4期12卷 618-631页

作者： Xin jia Lu HUANG miao SUN Wenbin LI National Institute of Metrology Beijing 100029China Yantai Tiancheng Machinery Co. Ltd.Yantai 264006China

Rolling bearings working in oscillating applications often suffer from false brinelling and fretting corrosion that limit their service *** present,the study of oscillation-induced failures is primarily dominated by a large number of sliding and bench ***,most of the previous work are not able to fully describe the two closely related but different failure *** this study,the origin and evolution of the two failures are thoroughly investigated under strictly controlled oscillating rolling *** results show that failure evolves from false brinelling to fretting corrosion under dry friction conditions regardless of the oscillation *** process is accompanied by a large area peeling and serious oxidation,and the oxygen content increases from 2.50 wt%to 21.22 wt%.Oxidation is a crucial factor in the evolution of false brinelling into fretting ***,the distribution of microwear and oxygen content depend on the oscillation *** lubrication conditions,the friction coefficient(COF)is smaller in the initial stage and led to local slip or transient instability of rolling ***,the size of the wear marks and COF increased and appeared to be larger than those under a dry friction ***,grease can separate the contact surfaces,only surface deformation owing to false brinelling and slight damage at the roughness level *** evolution of false brinelling and fretting corrosion is also closely related to residual *** brinelling often occurrs with residual stress accomulation,meanwhile,the residual stress increases from 120 to 300 *** peeling occurs,residual stress is *** failure pattern transformed from false brinelling to fretting corrosion and is accompanied by *** far,none of investigation is able to show satisfactory evolution of oscillating-induced failures,this study may contribute to more scientific understanding of rolling bearings against long-

关键词： oscillating false brinelling fretting corrosion wear residual stress

Influence of Human Activity Intensity on Habitat Quality in Hainan Tropical Rainforest National Park,China

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Chinese Geographical Science 2024年第3期34卷 519-532页

作者： HAN Nianlong YU miao jia Peihong ZHANG Yucheng HU Ke School of Geography and Tourism Huizhou UniversityHuizhou 516007China School of Public Administration Hainan Uni-versityHaikou 570228China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong KongChina School of Geographic Sciences and Remote Sensing Guangzhou UniversityGuangzhou 510006China School of Public Administration Nanjing Agricultural UniversityNanjing 210095China

Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding scope and intensity of human activity impact,the regional ecological security is facing serious challenges.A scientific assessment of the interrelationship between human activity intensity and habitat quality in the HTRNP is a prerequisite for achieving effective management of ecological disturbances caused by human activities and can also provide scientific strategies for the sustainable development of the *** on the land use change data in 2000,2010,and 2020,the spatial and temporal variations and the relationship between habitat quality(HQ)and human activity intensity(HAI)in the HTRNP were explored using the integrated valuation of ecosystem services and trade-offs(InVEST)*** dynamics and land use simulation models were also combined to conduct multi-scenario simulations of their *** results showed that during 2000–2020,the habitat quality of the HTRNP improved,the intensity of human activities decreased each year,and there was a negative correlation between the ***,the system dynamic model could be well coupled with the land use simulation model by combining socio-economic and natural *** simulation scenarios of the coupling model showed that the harmonious development(HD)scenario is effective in curbing the increasing trend of human activity intensity and decreasing trend of habitat quality,with a weaker trade-off between the two compared with the baseline development(BD)and investment priority oriented(IPO)*** maintain the authenticity and integrity of the HTRNP,effective measures such as ecological corridor construction,ecological restoration,and the implementation of ecological compensation policies need to be strengthened.

关键词： human activity intensity(HAI) habitat quality(HQ) bivariate spatial autocorrelation system dynamics model integrated valuation of ecosystem services and trade-offs(InVEST)model Hainan Tropical Rainforest National Park(HTRNP)of China

Damage on intestinal barrier function and microbial detoxification of deoxynivalenol:A review

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Journal of Integrative Agriculture 2024年第8期23卷 2507-2524页

作者： jia Chen Xinran Zhang Ziqi He Dongwei Xiong miao Long Key Laboratory of Livestock Infectious Diseases Ministry of Education/College of Animal Science and Veterinary Medicine ShenyangAgricultural UniversityShenyang 110866China

Deoxynivalenol(DON)is a mycotoxin that is produced by various species of Fusarium and is ubiquitous in food and *** low concentrations,it can cause metabolic disorders in animals and humans and,at high concentrations,it can lead to pathological changes in the *** impact of DON on human/animal health and animal productivity has thus attracted a great deal of attention around the *** causes severe damage to the intestine,including compromised intestinal barrier,mucosal damage,weakened immune function,and alterations in gut microbiota *** effects exacerbate intestinal infections and inflammation in livestock and poultry,posing adverse effects on overall ***,research into biological methods for DON detoxification is a crucial avenue for future *** includes the utilization of adsorption,enzymatic degradation,and other biological approaches to mitigate DON's impact,offering new strategies for prevention and treatment of DON-induced *** research will focus on identifying highly efficient detoxifying microorganisms or enzymes to reduce DON levels in food and feed,thereby mitigating its risks to both animals and human health.

关键词： deoxynivalenol(DON) intestinal barrier function mucus barrier immune function flora composition biological detoxification

Axial segregation characteristics and size-induced flow behavior of particles in a novel rotary drum with curved sidewalls

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Particuology 2024年第4期87卷 1-19页

作者： Qiuhua miao Wenchang Zhu Yudong Cao Peng Huang Chaobin Hu Minping jia School of Mechanical Engineering Southeast UniversityNanjing211189China jiangsu Key Laboratory for Elevator Inteligent Safety Changshu215500China

Particle mixing and segregation are common phenomena in rotary drums,which are challenging to be controlled and driven artificially in powder *** this work,the discrete element method(DEM)was applied to construct the novel rotary drum composed of different shaped curved *** varying the operation parameters of particle and sidewall shapes as well as the length-to-diameter(L/D)ratio of drums,the axial mixing and segregation processes of binary size-induced particles were *** results show that the axial flow velocity of the particle mixtures is noticeably weakened once the particle angularity increases,making the non-spherical particles to mix better in rotary drums compared to the spherical ***,in the short drums with size-induced spherical particles,the axial segregation characteristics are significantly enhanced by the convex sidewalls while suppressed by the concave ***,for size-induced non-spherical particles,the axial segregation structure can be present in rotary drums with plane and concave sidewalls while not in drums with convex ***,the axial segregation band structure of spherical particles eventually increases proportionally with the increased drum L/D *** contrast,the non-spherical particles cannot form obvious multi-proportional segregation bands.

关键词： Axial flow behaviors Size-induced particles Curved sidewalls Non-spherical particles Rotary drum

In-situ polymerized PEO-based solid electrolytes contribute better Li metal batteries:Challenges,strategies,and perspectives

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Journal of Energy Chemistry 2024年第5期92卷 548-571页

作者： Zhihui jia Yong Liu Haoming Li Yi Xiong Yingjie miao Zhongxiu Liu Fengzhang Ren School of Materials Science and Engineering Henan Key Laboratory of Non-Ferrous Materials Science&Processing TechnologyHenan University of Science and TechnologyLuoyang 471023HenanChina Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal new Materials and Advanced Processing Technology Henan University of Science and TechnologyLuoyang 471023HenanChina

Polyethylene oxide(PEO)-based solid polymer electrolytes(SPEs)with good electrochemical stability and excellent Li salt solubility are considered as one of the most promising SPEs for solid-state lithium metal batteries(SSLMBs).However,PEO-based SPEs suffer from low ionic conductivity at room temperature and high interfacial resistance with the electrodes due to poor interfacial contact,seriously hindering their practical *** an emerging technology,in-situ polymerization process has been widely used in PEO-based SPEs because it can effectively increase Li-ion transport at the interface and improve the interfacial contact between the electrolyte and ***,we review recent advances in design and fabrication of in-situ polymerized PEO-based SPEs to realize enhanced performance in *** merits and current challenges of various SPEs,as well as their stabilizing strategies are ***,various in-situ polymerization methods(such as free radical polymerization,cationic polymerization,anionic polymerization)for the preparation of PEO-based SPEs are *** addition,the application of in-situ polymerization technology in PEO-based SPEs for adjustment of the functional units and addition of different functional filler materials was systematically discussed to explore the design concepts,methods and working ***,the challenges and future prospects of in-situ polymerized PEO-based SPEs for SSLMBs are also proposed.

关键词： In-situ polymerization Polyethylene oxide Solid polymer electrolytes Lithium metal anodes

Extending Structures for Gel'fand-Dorfman Bialgebras

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Acta Mathematica Sinica,English Series 2024年第2期40卷 619-638页

作者： jia jia WEN Yan Yong HONG School of Mathematics Hangzhou Normal UniversityHangzhou 311121P.R.China

Gel'fand-Dorfman bialgebra,which is both a Lie algebra and a Novikov algebra with some compatibility condition,appeared in the study of Hamiltonian pairs in completely integrable *** also emerged in the description of a class special Lie conformal algebras called quadratic Lie conformal *** this paper,we investigate the extending structures problem for Gel'fand-Dorfman bialgebras,which is equivalent to some extending structures problem of quadratic Lie conformal ***,given a Gel'fand-Dorfman bialgebra(A,o,[.,.]),this problem is how to describe and classify all Gel'fand-Dorfman bialgebra structures on a vector space E(A⊂E)such that(A,o,[.,.])is a subalgebra of E up to an isomorphism whose restriction on A is the identity *** by the theories of extending structures for Lie algebras and Novikov algebras,we construct an object gH2(V,A)to answer the extending structures problem by introducing the notion of a unified product for Gel'fand-Dorfman bialgebras,where V is a complement of A in *** particular,we investigate the special case when dim(V)=1 in detail.

关键词： Gel'fand-Dorfman bialgebra Lie conformal algebra Extending structures problem Novikovalgebra

Historical biogeography and evolutionary diversification of Lilium(Liliaceae): New insights from plastome phylogenomics

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Plant Diversity 2024年第2期46卷 219-228页

作者： Nian Zhou Ke miao Changkun Liu Linbo jia Jinjin Hu Yongjiang Huang Yunheng Ji CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengduSichuan 610065China Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Population Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China

Here, we infer the historical biogeography and evolutionary diversification of the genus Lilium. For this purpose, we used the complete plastomes of 64 currently accepted species in the genus Lilium(14plastomes were newly sequenced) to recover the phylogenetic backbone of the genus and a timecalibrated phylogenetic framework to estimate biogeographical history scenarios and evolutionary diversification rates of Lilium. Our results suggest that ancient climatic changes and geological tectonic activities jointly shaped the distribution range and drove evolutionary radiation of Lilium, including the Middle Miocene Climate Optimum(MMCO), the late Miocene global cooling, as well as the successive uplift of the Qinghai-Tibet Plateau(QTP) and the strengthening of the monsoon climate in East Asia during the late Miocene and the Pliocene. This case study suggests that the unique geological and climatic events in the Neogene of East Asia, in particular the uplift of QTP and the enhancement of monsoonal climate, may have played an essential role in formation of uneven distribution of plant diversity in the Northern Hemisphere.

关键词： Asian monsoon Climatic changes Distribution range Evolutionary complexity Radiative diversification Species diversity Qinghai-Tibet Plateau(QTP)

Influence of different magnetic forces on the effect of colonic anastomosis in rats

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 860-870页

作者： Bo-Yan Tian miao-miao Zhang jia Ma Yi Lyu Xiao-Peng Yan Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina Department of Surgical Oncology Shaanxi Provincial People's HospitalXi'an 710068Shaanxi ProvinceChina

BACKGROUND Despite much work having been conducted on magnetic compression anastomo-sis(MCA)in the digestive tract,there are no reports on the influence of magnetic force on the *** To investigate the effect of different magnetic force magnets on the MCA of the digestive *** Two groups of magnets of the same sizes but different magnetic forces were designed and produced.A total of 24 Sprague-Dawley rats were randomly assigned into two groups(powerful magnet group and common magnet group),with 12 rats in each *** types of magnets were used to complete the colonic side-to-side anastomosis of the *** operation time and magnet discharge time were *** anastomotic specimens were obtained 4 wk after the operation and then the burst pressure and diameter of the anastomosis were measured,and the anastomosis was observed via the naked eye and subjected to histological *** The magnetic forces of the powerful and common magnet groups at zero distance were 8.26 N and 4.10 N,*** colonic side-to-side anastomosis was completed in all 24 rats,and the operation success rate and postoperative survival rate were 100%.No significant difference was noted in the operation time between the two *** magnet discharge time of the powerful magnet group was slightly longer than that of the common magnet group,but the difference was not statistically significant(P=0.513).Furthermore,there was no statistical difference in the burst pressure(P=0.266)or diameter of magnetic anastomosis(P=0.095)between the two *** gross specimens of the two groups showed good anastomotic healing,and histological observation indicated good mucosal continuity without differences on *** In the rat colonic side-to-side MCA model,both the powerful magnet with 8.26 N and the common magnet with 4.10 N showed no significant impact on the anastomosis establishment process or its effect.

关键词： Magnetosurgery Magnetic compression anastomosis Colonic anastomosis Magnetic force Rats

Geometric Constraints for Global Regularity of 3D Shear Thickening Fluids

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 205-210页

作者： jia-qi Yang Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518063China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China

We consider the relation between the direction of the vorticity and the global regularity of 3D shear thickening *** is showed that a weak solution to the non-Newtonian incompressible fluid in the whole space is stron... 详细信息

关键词： direction of the vorticity non-Newtonian fluid global regularity