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Enhancing strength and ductility.of AlSi10Mg fabricated by.selective laser melting by.TiB_(2)nanoparticles

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Journal of Materials Science & Technology 2022年第14期109卷 254-266页

作者： y.K.Xiao H.Chen Z.y.Bian T.T.Sun H.ding Q.y.ng y.Wu Q.Lian Z.Chen H.W.Wang State Key.Laboratory.of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China School of Materials Science&Engineering Shanghai Jiao Tong UniversityShanghai 200240China

In the metallic components fabricated by.the emerging selective laser melting(SLM)technology.most strategies used for strengthening the materials sacrifice the ductility.leading to the so-called strengthductility.*** the present study.we report that the strength and ductility.of materials can be enhanced simultaneously.by.introducing nanoparticles,which can break the trade-off of the metallic *** the case of in-situ nano-TiB_(2)decorated AlSi10Mg composites,the introduced nanoparticles lead to columnar-to-equiaxed transition,grain refinement and texture *** increasing content of nanoparticles,the strength increases ***,the ductility.first increases and then *** results show that the ductility.is controlled by.the competition between the crack-induced catastrophic fracture and ductile fracture associated with dislocation *** first increase of ductility.is mainly.attributed to the suppression of crack-induced catastrophic fracture when TiB_(2)nanoparticles *** the further increase of TiB_(2)nanoparticles,the subsequent decrease of ductility.is mainly.controlled by.dislocation ***,the materials will exhibit the optimum strength and ductility.combination in a certain range of TiB_(2)*** study.clarifies the phy.ical mechanism controlling ductility.for nano-TiB_(2)decorated Al Si10Mg composites,which provides the insights for the design of structural materials.

关键词： Selective laser melting Aluminium matrix composites Ductility Mechanical behavior Dislocations Cracks

A newly.unraveled 13.6-y.ar oscillation from GPS displacements and its potential implications for the dy.amic reference frame

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Science China Earth Sciences 2024年第10期67卷 3204-3212页

作者： Hao ding Weiping JIANG School of Geodesy.and Geomatics Hubei Luojia LaboratoryWuhan UniversityWuhan 430079China GNSS Research Center Wuhan UniversityWuhan 430079China

Numerous practical geodetic and geophy.ical applications necessitate precise measurements of GNSS displacements at the millimeter or sub-millimeter level. To attain such precision, it is imperative to identify.and analy.e the unidentified decadal signals inherent in the GPS displacements. In this research, we employ.the optimal sequence estimation method to effectively.detect an about 13.6-y.ar oscillational signal with an excited amplitude of 3.6±1.2 mm in the U-components of the GPS displacements. It is noteworthy.that this signal demonstrates a consistent spatial pattern characterized by.the spherical harmonic y.(2,-2). We conduct a comparative analy.is with the 13.6-y.ar oscillation observed in length-of-day.variations(and geomagnetic records), finding that they.are in reverse phase. After eliminating the Earth's external excitation sources through the utilization of two distinct in-situ hy.rological records, we suggest that the 13.6-y.ar GPS signal may.come from the internal motions within the Earth. However, the specific excitation source and the detailed phy.ical mechanism remain uncertain. Additionally. we develop a mathematical displacement model to explain the 13.6-y.ar signal. Our findings indicate that this signal can result in displacements of up to 1.37 mm and velocity.effects of 0.63 mm/y.(for U-component) at maximum. These results underscore the necessity.of incorporating this 13.6-y.ar signal into the construction and maintenance of a dy.amic reference frame at the millimeter level.

关键词： GPS displacements Decadal changes 13.6-y.ar oscillation Displacement model Dy.amic reference frame

A qualitative and quantitative study.of color emotion using valence-arousal

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Frontiers of Computer Science 2012年第4期6卷 469-476页

作者： Shangfei WANG Rui ding Key.Lab of Computing and Communicating Software of Anhui Province School of Computer Science and TechnologyUniversity of Science and Technology of ChinaHefei 230027China

This paper describes qualitative and quantita- tive analy.is of color emotion dimension expression using a standard device-independent colorimetric sy.tem. To collect color emotion data, 20 subjects are required to report their emotion responses, using a valence-arousal emotion model, to 52 color samples that are chosen from CIELAB Lch color spaces. Qualitative analy.is, including analy.is of variance （ANOVA）, Pearson＇s correlation and Spearman＇s rank cor- relation, shows that significant differences exist between re- sponses to achromatic and chromatic stimuli, but there are no significant differences between chromatic samples. There is a positive linear relationship between lightness/chroma and valence-arousal dimensions. Subsequently. several clas- sic predictors are used to quantitatively.predict emotion in- duced by.color attributes. Furthermore, several explicit color emotion models are developed by.using multiple linear re- gression with stepwise and pace regression. Experimental results show that chroma and lightness have stronger effects on emotions than hue, which is consistent with our qualitative results and other psy.hological studies. Arousal has greater predictive value than valence.

关键词： color emotion valence and arousal qualitative quantitative

Preliminary.Study.on Corrosion Behaviour of Carbon Steel in Oil–Water Two-Phase Fluids

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Journal of Materials Science & Technology 2015年第12期31卷 1274-1281页

作者： Z.y.Hu D.L.Duan S.H.Hou X.J.ding S.Li Institute of Metal Research Chinese Academy of Sciences

The corrosion behavior of ty.e 1045（AISI） carbon steel（CS） in oil-water fluids was investigated by.considering the surface wetting state as the breakthrough *** surface water wetting percentage（SWWP）and corrosion weight loss of CS in different oil-water fluids were *** morphology.and composition of the corrosion films were detected via scanning electron microscopy.electron-probe facescanning technology.and Fourier-transform infrared *** results indicated that the corrosion weight loss of CS in the oil-water fluids corresponded with SWWP and that the corrosion process was influenced by.the participation of oil.

关键词： Carbon steel Corrosion behavior Wetting Fluid flow Fourier transform infrared(FTIR) spectroscopy

Inhomogeneous Cauchy.Riemann equation in Octonion space

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Applied Mathematics(A Journal of Chinese Universities) 2015年第4期30卷 447-452页

作者： GONG ding-dong Department of Mathematical Science Zhejiang Sci-Tech University

The integral representation of differentiable functions in Octonion space is obtained and the explicit solution of the inhomogeneous Cauchy.Riemann equation is given by.integral representation. As an application, the ... 详细信息

关键词： Octonion integral representation of differentiable functions inhoraogeneous Cauchy.RiemannEquation Cousin problem.

New Generalized R-KKM Ty.e Theorems in General Topological Spaces and Applications

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Acta Mathematica Sinica,English Series 2007年第10期23卷 1869-1880页

作者： Xie Ping ding College of Mathematics and Software Science Sichuan Normal University Chengdu 610066 P. R. China

In this paper, some new generalized R-KKM ty.e theorems for generalized R-KKM mappings with finitely.closed values and with finitely.open values are established in noncompact topological spaces without any.convexity.structure under much weaker assumptions. As applications, some new minimax inequalities, saddle point theorem and equilibrium existence theorem for equilibrium problems with lower and upper bounds are established in general noncompact topological spaces. These theorems unify.and generalize many.known results in the literature.

关键词： generalized R-KKM mapping finitely.closed-valued (open-valued) generalized R-KKM ty.e theorem minimax inequality saddle point equilibrium problem

Continuous Selection,Collectively.Fixed Points and Sy.tem of Coincidence Theorems in Product Topological Spaces

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Acta Mathematica Sinica,English Series 2006年第6期22卷 1629-1638页

作者： Xie Ping ding College of Mathematics and Software Science Sichuan Normal University Chengdu 610066 P. R. China

Some new continuous selection theorems are first proved in noncompact topological spaces. As applications, some new collectively.fixed point theorems and coincidence theorems for two families of set-valued mappings defined on product space of noncompact topological spaces are obtained under very.weak assumptions. These results generalize many.known results in recent literature.

关键词： continuous selection collectively.fixed point coincidence theorem for two families of set-valued mappings FC-space

Low back pain and osteoarthritis pain:a perspective of estrogen

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Bone Research 2023年第3期11卷 443-456页

作者： Huiwen Pang Shihui Chen David M.Kly.e David Harrich Weny.an ding Sidong y.ng Felicity.y.Han Australian Institute for Bioengineering and Nanotechnology The University of QueenslandSt.LuciaBrisbaneQLD 4072Australia NHMRC Centre of Clinical Research Excellence in Spinal Pain Injury and HealthThe University of QueenslandSt.LuciaBrisbaneQLD 4072Australia Department of Cell and Molecular Biology QIMR Berghofer Medical Research InstituteHerstonQLD 4006Australia Department of Spine Surgery The Third Hospital of Hebei Medical University139 Ziqiang RoadShijiazhuang 050051China Hebei Joint International Research Center for Spinal Diseases 139 Ziqiang RoadShijiazhuang 050051China

Low back pain(LBP)is the world's leading cause of disability.and is increasing in prevalence more rapidly.than any.other pain *** disc(IVD)degeneration and facet joint osteoarthritis(FJOA)are two common causes of LBP,and both occur more frequently.in elderly.women than in other ***,osteoarthritis(OA)and OA pain,regardless of the joint,are experienced by.up to twice as many.women as men,and this difference is amplified during *** in estrogen may.be an important contributor to these pain *** for estrogen have been found within IVD tissue and nearby.joints,highlighting the potential roles of estrogen within and surrounding the IVDs and *** addition,estrogen supplementation has been shown to be effective at ameliorating IVD degeneration and OA progression,indicating its potential use as a therapeutic agent for people with LBP and OA *** review comprehensively.examines the relationship between estrogen and these pain conditions by.summarizing recent preclinical and clinical *** potential molecular mechanisms by.which estrogen may.relieve LBP associated with IVD degeneration and FJOA and OA pain are discussed.

关键词： agent degeneration pain

Bird guild loss and its determinants on subtropical land-bridge islands, China

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Chinese Birds 2015年第2期6卷 99-106页

作者： Zhifeng ding Kenneth James Feeley.Huijian Hu Ping ding The Key.Laboratory.of Conservation Biology.for Endangered Wildlife of the Ministry.of Education College of Life Sciences Zhejiang UniversityZijin’gang Campus Guangdong Entomological Institute & South China Institute of Endangered Animals Department of Biological Sciences Florida International University Center for Tropical Plant Conservation Fairchild Tropical Botanic Garden

Background: The guild concept is useful for understanding the community.structure in a land-bridge island sy.tem,but most fragmentation studies have focused only.on the importance of island area and isolation, other island attributes such as perimeter-area ratio(PAR) were overlooked or ***: We have adopted a guild approach to investigate the impacts of island attributes on bird guild richness on a set of 41 recently.isolated land-bridge islands in the Thousand Island Lake(TIL), ***: We found insectivores had the largest number of species(34 species), fol owed by.understory.foraging guilds(28 species), omnivores(27 species) and canopy.guilds(25 species). Furthermore, our data showed that migrants and residents responded equal y.to island area, insectivores and understory.guilds were sensitive to island area but omnivores and canopy.guilds were not very.sensitive. Most guild richness was determined by.island area, except for omnivores and canopy.***: Although PAR or habitat diversity.found to be important for bird species richness, our results highlight the importance of island area in maintaining bird diversity.in fragmented island sy.tems.

关键词： Bird guilds Island area Land-bridge islands PAR Thousand Island Lake z values