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microscale shaping and rounding of ridge arrays and star pattern features on nickel mould via electrochemical polishing

The International Young Scholars’ Symposium on Rock mechanics

作者： Z.Y.Fan H.W.Huang d.m.zhang Key Laboratory of Geotechnical and Underground Engineering of ministry of Education department of Geotechnical Engineering Tongji University Shanghai China

＜正＞With construction of city subway and cross-river tunnels,shield driven tunnels are widely used owing to its technological and economic ***-staggering and staggering installation pattern of segments arc two main types of shield *** installation patterns of segments cause discrepancy of mechanical *** model tunnels of non-staggering and staggering installation patterns are made from *** circumferential and longitudinal joints are modeled by polyethylene *** tests of two-ring model tunnels with different installation patterns are conducted and radial displacements of model tunnels are measured;loading tests of fifty-ring model tunnels with different installation patterns are conducted, circumferential strains are recorded,and then the distribution of bending moments and axial forces of lining ring are *** results show that the transverse bending rigidity of staggering tunnel is larger than that of non- staggering tunnel and the deformation of staggering tunnel is smaller in the same *** distribution forms of internal forces are basically similar under different installation patterns and the absolute values of maximum or minimum axial force and bending moment in tunnel of staggering installation are larger than corresponding values in tunnel of non-staggering installation.

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Advances in manufacturing 2024年第2期12卷 207-226页

作者： Sana Zaki Nan zhang michael d.Gilchrist School of mechanical and materials Engineering University College DublinBelfieldDublin 4Ireland

High quality micro mould tools are critical for ensuring defect-free production of micro injection moulded *** demoulding stage of the micro injection moulding can adversely affect the surface integrity due to friction,adhesion and thermal stresses between the metallic mould and polymeric replicated *** the present work,we propose the use of precision electropolishing(EP)as a shaping and polishing process to control the draft angle and fillet radius of micro features in order to ease *** defects that occur in replicated polymer parts include cracks,burrs and distorted features.A nickel mould having multiple linear ridges and star shape patterns was designed for the present investigation to have characteristic dimensions ranging from 10μm to 150μm and with various aspect ratios to study the effect of electropolishing on modifying the shape of micro features and surface morphology.A transient 2d computational analysis has been conducted to anticipate the effect of shaping on the Ni mould after electrochemical polishing with non-uniform material removal rates,based on the distribution of current *** experimental results indicate that after shaping using EP,the draft angle of star-patterns and linear patterns can be effectively increased by approximately 3.6°,while the fillet radius increases by up to 5.0μ*** controlling the electropolishing process,the surface roughness can be maintained under 50 *** work uses a green and environmental friendly nickel sulfamate electrolyte which can be effective for shaping of nickel micro features without causing any surface deposition.

关键词： micro feature shaping and electropolishing micro mould tools Green electrolyte demoulding micro patterns

Prediction for long-term settlement of Shanghai Yangtze River Tunnel

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Prediction for long-term settlement of Shanghai Yangtze Rive...

Optical measurements of dissolved organic matter as proxies for COd_(mn)and BOd_(5)in plateau lakes

作者： d.m.zhang,H.L.Bao & H.W.Huang Key Laboratory of Geotechnical & Underground Engineering,ministry of Education, Tongji University,Shanghai,P.R.China department of Geotechnical Engineering,School of Civil Engineering,Tongji University, Shanghai,P.R.China

The drainage condition combining with the time-dependent properties of the surrounding soil play an important role in the evolution of long-term settlement of *** paper presents an analytical solution for the prediction of long-term settlement of Shanghai Yangtze River *** complex conformal transformation is used to map the considered region in the physical plane onto a circular ring region in the image *** on the visco-elastic Terzaghi - Rendulic consolidation theory,assuming that the tunnel is partially sealed with partial drainage boundary,the long-term settlement of the tunnel is studied.

关键词： Prediction for long-term settlement of Shanghai Yangtze River Tunnel

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Environmental Science and Ecotechnology 2024年第3期19卷 132-138页

作者： Xuan Yang Yongqiang Zhou Xiaoying Yang Yunlin zhang Robert G.m.Spencer Justin d.Brookes Erik Jeppesen Hucai zhang Qichao Zhou Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental SciencesYunnan UniversityKunming650500China Institute of International River and Eco-security Yunnan UniversityKunming650500China Zhejiang College of Security Technology Wenzhou325016China Taihu Laboratory for Lake Ecosystem Research State Key Laboratory of Lake Science and EnvironmentNanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing210008China department of Earth Ocean and Atmospheric ScienceFlorida State UniversityTallahassee32306United States Water Research Centre School of Biological ScienceThe University of AdelaideAdelaide5005Australia department of Ecoscience Aarhus UniversityAarhus8000Denmark Sino-danish Centre for Education and Research Chinese Academy of SciencesBeijing100101China Limnology Laboratory Department of Biological Sciences and Centre for Ecosystem Research and ImplementationMiddle East Technical UniversityAnkara06800Turkey Institute of marine Sciences Middle East Technical UniversityErdemliMersin33731Turkey Yunnan Key Laboratory of Pollution Process and management of Plateau Lake-Watershed Yunnan Research Academy of Eco-environmental SciencesKunming650034China

The presence of organic matter in lakes profoundly impacts drinking water supplies,yet treatment processes involving coagulants and disinfectants can yield carcinogenic disinfection *** assessments of organic matter,such as chemical oxygen demand(COd_(mn))and biochemical oxygen demand(BOd_(5)),are often ***,optical measurements of dissolved organic matter(dOm)offer a rapid and reliable means of obtaining organic matter composition *** we employed dOm optical measurements in conjunction with parallel factor analysis to scrutinize COd_(mn)and BOd_(5)*** was performed using an independent dataset encompassing six lakes on the Yungui Plateau from 2014 to 2016(n=256).Leveraging multiple linear regressions(mLRs)applied to dOm absorbance at 254 nm(a254)and fluorescence components C1-C5,we successfully traced COd_(mn)and BOd_(5)variations across the entire plateau(68 lakes,n=271,R^(2)>0.8,PdOm optical indices yielded superior estimates(higher R^(2))of COd_(mn)and BOd_(5)during the rainy season compared to the dry season and demonstrated increased accuracy(R^(2)>0.9)in mesotrophic lakes compared to oligotrophic and eutrophic *** study underscores the utility of mLR-based dOm indices for inferring COd_(mn)and BOd_(5)variability in plateau lakes and highlights the potential of integrating in situ and remote sensing platforms for water pollution early warning.

关键词： dissolved organic matter Chemical oxygen demand Biochemical oxygen demand Water quality Yungui plateau lakes

Global patterns and ecological drivers of taxonomic and phylogenetic endemism in angiosperm genera

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Plant diversity 2024年第2期46卷 149-157页

作者： Hong Qian Brent d.mishler Jian zhang Shenhua Qian Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA University and Jepson Herbaria Department of Integrative BiologyUniversity of CaliforniaBerkeleyCA 94720-2465USA Center for Global Change and Complex Ecosystems Zhejiang Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment Ministry of EducationChongqing UniversityChongqing 400045China

Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation,extinction,and dispersal have influenced current ***,we investigated geographic patterns and ecological drivers of taxonomic and phylogenetic endemism of angiosperm genera across the *** identify centers of paleo-endemism and neo-endemism of angiosperm genera,and show that they are mostly located in the Southern Hemisphere in tropical and subtropical regions,particularly in Asia and *** categories of phylogenetic endemism centers can be differentiated using current climate *** climate,historical climate change,and geographic variables together explained~80%of global variation in taxonomic and phylogenetic endemism,while 42-46%,1%,and 15%were independently explained by these three types of variables,*** our findings show that past climate change,current climate,and geography act together in shaping endemism,which are consistent with the findings of previous studies that higher temperature and topographic heterogeneity promote *** study showed that many centers of phylogenetic endemism of angiosperms,including regions in Amazonia,Venezuela,and west-central tropical Africa that have not previously been identified as biodiversity hotspots,are missed by taxon-based measures of endemism,indicating the importance of including evolutionary history in biodiversity assessment.

关键词： Angiosperm Current climate Endemism Historical climate change Topographic heterogeneity

On self-affine tiles that are homeomorphic to a ball

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Science China mathematics 2024年第1期67卷 45-76页

作者： Jorg m.Thuswaldner Shu-Qin zhang mathematics and Statistics University of LeobenLeoben 8700Austria School of mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China

Let m be a 3×3 integer matrix which is expanding in the sense that each of its eigenvalues is greater than 1 in modulus and let d?Z^(3)be a digit set containing|det m|*** the unique nonempty compact set T=T(m,d)defined by the set equation mT=T+d is called an integral self-affine tile if its interior is *** d is of the form d={0,v,...,(|det m|-1)v},we say that T has a collinear digit *** present paper is devoted to the topology of integral self-affine tiles with collinear digit *** particular,we prove that a large class of these tiles is homeomorphic to a closed 3-dimensional ***,we show that in this case,T carries a natural CW complex structure that is defined in terms of the intersections of T with its neighbors in the lattice tiling{T+z:z∈Z^(3)}induced by *** CW complex structure is isomorphic to the CW complex defined by the truncated octahedron.

关键词： self-afine sets tiles and tilings low-dimensional topology truncated octahedron

Sparse-Grid Implementation of Fixed-Point Fast Sweeping WENO Schemes for Eikonal Equations

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Communications on Applied mathematics and Computation 2024年第1期6卷 3-29页

作者： Zachary m.miksis Yong-Tao zhang department of Applied and Computational mathematics and Statistics University of Notre DameNotre DameIN46556USA

Fixed-point fast sweeping methods are a class of explicit iterative methods developed in the literature to efficiently solve steady-state solutions of hyperbolic partial differential equations(PdEs).As other types of fast sweeping schemes,fixed-point fast sweeping methods use the Gauss-Seidel iterations and alternating sweeping strategy to cover characteristics of hyperbolic PdEs in a certain direction simultaneously in each sweeping *** resulting iterative schemes have a fast convergence rate to steady-state ***,an advantage of fixed-point fast sweeping methods over other types of fast sweeping methods is that they are explicit and do not involve the inverse operation of any nonlinear local ***,they are robust and flexible,and have been combined with high-order accurate weighted essentially non-oscillatory(WENO)schemes to solve various hyperbolic PdEs in the *** multidimensional nonlinear problems,high-order fixed-point fast sweeping WENO methods still require quite a large amount of computational *** this technical note,we apply sparse-grid techniques,an effective approximation tool for multidimensional problems,to fixed-point fast sweeping WENO methods for reducing their computational ***,we focus on fixed-point fast sweeping WENO schemes with third-order accuracy(zhang et al.2006[41]),for solving Eikonal equations,an important class of static Hamilton-Jacobi(H-J)*** experiments on solving multidimensional Eikonal equations and a more general static H-J equation are performed to show that the sparse-grid computations of the fixed-point fast sweeping WENO schemes achieve large savings of CPU times on refined meshes,and at the same time maintain comparable accuracy and resolution with those on corresponding regular single grids.

关键词： Fixed-point fast sweeping methods Weighted essentially non-oscillatory(WENO)schemes Sparse grids Static Hamilton-Jacobi(H-J)equations Eikonal equations

Viscoelastic potential flow instability theory of Rivlin-Ericksen electrified fluids of cylindrical interface

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Journal of Ocean Engineering and Science 2024年第4期9卷 311-316页

作者： d.m.mostafa department of mathematics College of ScienceQassim UniversityPO Box 6644Buraidah 51452Saudi Arabia department of mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

A linear electrohydrodynamic Kelvin-Helmholtz instability of the interface between two viscoelastic Rivlin-Ericksen fluids enclosed by two concentric horizontal cylinders has been studied via the viscoelastic potential flow *** dispersion equation of complex coefficients for asymmetric disturbance has been obtained by using normal mode *** stability criteria are analyzed theoretically and illustrated *** imaginary part of growth rate is plotted versus the wave *** influences of dynamic viscoelastic,uniform velocities,Reynolds number,electric field,dynamic viscosity,density fluids ratio,dielectric constant ratio and inner fluid fraction on the stability of the system are *** study finds its significance in Ocean pipelines to transfer oil or gas such as Eastern Siberia-Pacific Ocean oil pipeline.

关键词： Rivlin-Ericksen fluid Cylindrical flow Viscoelastic potential flow Electrohydrodynamics stability

One-neutron stripping process in the^(209)Bi(^(6)Li,^(5)Li)^(210)Bi*reaction reaction

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Nuclear Science and Techniques 2024年第6期35卷 120-129页

作者： Gao-Long zhang Zhen-Wei Jiao Guang-Xin zhang E.N.Cardozo B.Paes Shi-Peng Hu Jian-Qiang Qian daniele mengoni Wei-Wei Qu Cong-Bo Li Yun Zheng Huan-Qiao zhang Hui-Bin Sun Nan Wang Chun-Lei zhang J.J.Valiente-dobón d.Testov m.mazzocco A.Gozzelino C.Parascandolo d.Pierroutsakou m.La Commara A.Goasduff d.Bazzacco d.R.Napoli F.Galtarossa F.Recchia A.Illana S.Bakes I.Zanon S.Aydin Gde Angelis m.Siciliano R.menegazzo S.m.Lenzi S.Akkoyun L.F.Canto J.Lubian School of Physics Beihang UniversityBeijing 100191China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Instituto de Física Universidade Federal Fluminense24210-340 NiteróiRio de JaneiroBrazil Laboratorio TANdAR Comisión Nacional de Energía AtómicaBKNA1650 San MartíınArgentina Institute for Advanced Study in Nuclear Energy and Safety Shenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Research and manufacture of High Purity Germanium materials and Fetectors Shenzhen UniversityShenzhen 518060China INFN Sezione di PadovaPaduaItaly dipartimento di fisica Astronomia dell’Universita di padova PaduaItaly State Key Laboratory of Radiation medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China China Institute of Atomic Energy Beijing 102413China The Key Laboratory of Beam Technology and material modification of ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Laboratori Nazionali di Legnaro INFN35020 LegnaroItaly INFN Sezione di Napoli80126 NaplesItaly dipartimento di Farmacia Universitàdi Napoli“Federico II”80131 NaplesItaly department of Natural and mathematical Sciences Faculty of EngineeringTarsus University33480 MersinTurkey Physics division Argonne National LaboratoryLemontILUSA department of Physics Sivas Cumhuriyet UniversitySivasTurkey Instituto de Física Universidade Federal do Rio de JaneiroRio de Janeiro CP 6852821941-972Brazil

One-neutron stripping process between^(6)Li and^(209)Bi was studied at 28,30,and 34 meV using the in-beamγ-ray spectroscopy ***γ-γcoincident analysis clearly identified twoγ-rays feeding the ground and long-lived isomeric states,which were employed to determine the cross *** one-neutron stripping cross sections were similar to the cross sections of complete fusion in the^(6)Li+^(209)Bi system,but the one-neutron stripping cross sections decreased more gradually at the sub-barrier region.A coupled-reaction-channel calculation was performed to study the detailed reaction mechanism of the one-neutron stripping process in^(6)*** calculations indicated that the first excited state of 5 Li is critical in the actual one-neutron transfer mechanism,and the valence proton of 209Bi can be excited to the low-lying excited state in(^(6)Li,^(5)Li)reaction,unlike in the(d,p)reaction.

关键词： Transfer reaction Weakly bound nuclei Cross section