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A look into the past, present and future potential distributions of Talinopsis frutescens, a North American endemic lineage closely related to Cactaceae

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Journal of Arid Land 2020年第1期12卷 104-114页

作者： Mónica I MIGUEL-VÁZQUEZ Yasser S LÓPEZ DE OLMOS r Gilberto OCAMPO Department of Biology Basic Sciences CenterAutonomous University of Aguascalientes940 University AvenueAguascalientes 20130Mexico Biological and Health Sciences PhD Program Department of BiologyBiological and Health Sciences DivisionAutonomous Metropolitan UniversityIztapalapa 09340Mexico

Talinopsis frutescens(Anacampserotaceae,a family that is close related to Cactaceae)is a succulent species endemic to North *** aim of this study was to explore,using Ecological Niche Modeling(ENM),changes in potential distribution ranges considering different climate scenarios:past conditions during the Last Inter Glacial(LIG)and the Last Glacial Maximum(LGM),the present and projections for 2070(rCP 2.6 to 8.5).A pattern of contraction is observed during the LIG,which agrees with other studies focused in species from arid *** pattern was followed by a migration towards the south during the LGM and a possible recent expansion to the north as is observed in the present *** future projections show the same contraction and fragmentation patterns,resulting in three discontinuous areas:the northern part of the Chihuahuan Desert,the southern-central part of the Mexican Plateau,and the smallest one in the Tehuacán-Cuicatlán *** projections for future scenarios agree with other studies and support that global climate change tends to alter the current distribution of arid environment species.

关键词： Anacampserotaceae Caryophyllales ecological niche modeling succulent plants potential distribution

Stable Fano-like plasmonic resonance: its impact on the reversal of far-and near-field optical binding force

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Communications in Theoretical Physics 2020年第4期72卷 89-105页

作者： Hamim Mahmud rivy M r C Mahdy Nabila Masud Ziaur rahman Jony Saikat Chandra Das Department of Electrical&Computer Engineering North South UniversityBashundharaDhaka1229Bangladesh School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyang Ave639798 Singapore Pi Labs Bangladesh LTD ARA Bhaban39Kazi Nazrul Islam AvenueKawran BazarDhaka 1215Bangladesh

Even for a 100 nm interparticle distance or a small change in particle shape,optical Fano-like plasmonic resonance mode usually vanishes *** would be remarkable if stable Fano-like resonance could somehow be achieved in distinctly shaped nanoparticles for more than 1μm interparticle distance,which corresponds to the far electromagnetic field *** such far-field Fano-like plasmonic resonance can be achieved,controlling the reversal of the far-field binding force can be attained,like the currently reported reversals for near-field *** this work,we have proposed an optical set-up to achieve such a robust and stable Fano-like plasmonic resonance,and comparatively studied its remarkable impact on controlling the reversal of near-and far-field optical binding *** our proposed set-up,the distinctly shaped plasmonic tetramers are half immersed(***-benzene)in an inhomogeneous dielectric interface and illuminated by?circular?polarized *** have demonstrated significant differences between near-and far-field optical binding forces along with the Lorentz force field,which partially depends on the object’s shape.A clear connection is shown between the far-field binding force and the resonant modes,along with a generic mechanism to achieve controllable Fano-like plasmonic resonance and the reversal of the optical binding force in both far-and near-field configurations.

关键词： Fano resonance optical binding force Lorentz force plasmonic tetramer

Synthesis and luminescence of Eu3+ doped nanocrystalline TiO2 spheres

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Journal of rare Earths 2019年第11期37卷 1121-1125页

作者： M.Lysien K.Fiaczyk r.Tomala F.Granek W.Strek Institute of Low Temperature and Structure research Polish Academy of ScienceOkolna 2Wroclaw50-422Poland XTPL S.A. Stabtowicka 147Wroctaw54-066Poland

Eu^3+doped TiO2 anatase spheres were obtained by modified sol-gel ***(110-250 nm)are composed of smaller(5-15 nm)nanocrystals and exhibit red emission under UV light *** were synthesized by multi-step method from glycolated titania *** doped(1.0 mol%)and non-doped spheres were *** optical and structural properties were compared by materials characterization methods,such as X-ray powder diffraction,transmission electron microscopy and PL *** TiO2 spheres are crystalline phase pure and exhibit high luminescence intensity.

关键词： Titanium dioxide Nanophosphors rare earth elements Europium doped nanoparticles Luminescence

Comparative Study on the Corrosion resistance of Al–Cr–Fe Alloy Containing Quasicrystals and Pure Al

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Journal of Materials Science & Technology 2016年第10期32卷 1054-1058页

作者： r.T.Li Vinod K.Murugan Z.L.Dong K.A.Khor School of Mechanical and Aerospace Engineering Nanyang Technological University 50 Nanyang AvenueSingapore 639798 Singapore School of Materials Science and Engineering Nanyang Technological University50 Nanyang Avenue Singapore 639798Singapore

Al-Cr-Fe alloy containing quasicrystals has been consolidated using spark plasma sintering（SPS）. Its corrosion resistance properties were comparatively investigated with pure Al by electrochemical methods in 3.5 wt% NaCl solution. Their corrosion current density was also compared with that of three commercial steels-316 stainless steel, AISI 440C stainless steel and AISI H13 tool steel. Al-Cr-Fe alloy exhibits nobler corrosion potential and evident passivation with a potential range of around 150 mV while no passivation of pure Al sample is seen. The corrosion resistance of Al-Cr-Fe alloy is less than that of pure Al, but is close to that of 316 stainless steel and superior to that of AISI 440C stainless steel and AISI H13 tool steel.

关键词： Quasicrystal Spark plasma sintering Microstructure Corrosion resistance

Age and sex specific timing, frequency, and spatial distribution of horseshoe crab spawning in Delaware Bay:Insights from a large-scale radio telemetry array

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Current Zoology 2010年第5期56卷 563-574页

作者： David r.SMITH Lorne J.BrOUSSEAU Mary T. MANDT Michael J.MILLArD USGS Leetown Science Center Cornell University Cooperative Extension U.S. Fish and Wildlife Service

To study horseshoe crab Limulus polyphemus spawning behavior and migration over a large-spatial extent （〉100 km）, we arrayed fixed station radio receivers throughout Delaware Bay and deployed radio transmitters and archival tags on adult horseshoe crabs prior to their spawning season. We tagged and released 160 females and 60 males in 2004 and 217 females in 2005. The array covered approximately 140 km of shoreline. recapture rates were 〉70% with multi-year recaptures. We categorized adult age by carapace wear. Older females tended to spawn earlier in the season and more frequently than young females, but those tendencies were more apparent in 2004 when spawning overall occurred earlier than in 2005 when spawning was delayed possibly due to decreased water temperatures. Timing of initial spawning within a year was correlated with water temperature. After adjusting for day of first spring tide, the day of In＇st spawning was 4 days earlier for every 1 degree （℃） rise in mean daily water temperature in May. Seventy nine % of spawning occurred during nighttime high tides. Fifty five % of spawning occurred within 3 d of a spring tide, which was slightly higher than the 47% expected if spawning was uniformly distributed regardless of tidal cycle. Within the same spawning season, males and females were observed spawning or intertidally resting at more than one beach separated by 〉5 kin. Between years, most （77%） did not return to spawn at the same beach. Probability of stranding was strongly age dependent for males and females with older adults experiencing higher stranding rates. Horseshoe crabs staging in the shallow waters east of the channel spawned exclusively along the eastern （N J） shoreline, but those staging west of the channel spawned throughout the bay. Overall, several insights emerged from the use of radio telemetry, which advances our understanding of horseshoe crab ecology and will be useful in conserving the Delaware Bay horseshoe crab population and habita

关键词： Spawning behavior Marine arthropod Xiphosurid Limulus polyphemus Delaware Bay radio telemetry

Investigation of dry sliding wear properties of multi-directional forged Mg-Zn alloys

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Journal of Magnesium and Alloys 2019年第3期7卷 444-455页

作者： S.ramesh Gajanan Anne H.Shivananda Nayaka Sandeep Sahu M.r.ramesh Department of Mechanical Engineering National Institute of Technology KarnatakaSurathkal 575025India Department of Mechanical Engineering Shri Madhwa Vadiraja Institute of Technology and ManagementUdupiKarnataka 574115India Department of Materials Science and Engineering Indian Institute of Technology KanpurKanpur 208016India

Effect of multi-directional forging(MDF)on wear properties of Mg-Zn alloys(with 2,4,and 6wt%Zn)is *** sliding wear test was performed using pin on disk machine on MDF processed and homogenized *** behavior of samples was analyzed at loads of ION and 20 N,with sliding distances of 2000m and 4000m,at a sliding velocity of 3m/*** of worn samples were observed under scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),and x-ray diffraction(XrD)and the results were *** properties were evaluated using microhardness *** 5 passes of MDF,the average grain size was found to be 30±4p m,22±3 pm,and 18±3 pm,in Mg-2%Zn,Mg-4%Zn,and Mg-6%Zn alloys,respectively,with significant improvement in hardness in all *** resistance was improved after MDF processing,as well as,with increment in Zn content in Mg ***,it decreased when the load and the sliding distance *** surface exhibited ploughing,delamination,plastic deformation,and wear debris along sliding direction,and abrasive wear was found to be the main mechanism.

关键词： Multi-directional forging Mg-Zn alloy Microhardness Wear Coefficient of friction

Toeplitz Operators on Dirichlet Spaces

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Acta Mathematica Sinica,English Series 2001年第4期17卷 643-648页

作者： Yu Feng LU Shun Hua SUN Department of Applied Mathematics, Dalian University of Technology, Dalian 116024, P. r. China Department of Mathematics, Sichuan University, Chengdu 610064, P. r. China Department of Mathematics, Sichuan University, Chengdu 610064, P. r. China Department of Applied Mathematics Dalian University of Technology Dalian 116024 P. R. China Department of Mathematics Sichuan University Chengdu 610064 P. R. China

In this paper we study Toeplitz operators on Dirichlet spaces and describe the boundedness and compactness of Toeplitz operators on Dirichlet spaces. Meanwhile, we give density theorems for Toeplitz operators on Diric... 详细信息

关键词： Dirichlet space Toeplitz operator Compact operator Strong operator topology

The ε-Complexity of the Approximate Solution of Integral Equations with Isotropic Kernels

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Acta Mathematica Sinica,English Series 2002年第4期18卷 679-686页

作者： Wan MA Gen Sun FANG College of Mathematics & Information Science of Wenzhou University, Wenzhou 325027, P. r. China Department of Mathematics, Beijing Normal University, Beijing 100875, P. r. China College of Mathematics & Information Science of Wenzhou University Wenzhou 325027 P. R. China Department of Mathematics Beijing Normal University Beijing 100875 P. R. China

The exact order of s-complexity is determined in L_p (2≤p≤∞) spaces for the second kind of Fredholm integral equations with kernels belonging to an isotropic Sobolev class.

关键词： Fredholm equation ε-complexity Sobolev classes

State Transition Induced by Self-Steepening and Self Phase-Modulation

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Chinese Physics Letters 2014年第1期31卷 33-36页

作者： He Jing-Song Xu Shu-Wei M. S. ruderman r. Erdélyi Department of Mathematics Ningbo University Ningbo 315211 DAMTP University of Cambridge Cambridge CB3 0WA UK School of Mathematics University of Science and Technology of China Hefei 230026 Solar Physics and Space Plasma research Centre University of Sheffield Sheffield S3 7RH UK

We present a rational solution for a mixed nonlinear Schr6dinger （MNLS） equation. This solution has two free parameters, a and b, representing the contributions of self-steepening and self phase-modulation （SPM） of an associated physical system, respectively. It describes five soliton states： a paired bright-bright soliton, a single soliton, a paired bright-grey soliton, a paired bright-black soliton, and a rogue wave state. We show that the transition among these live states is induced by self-steepening and SPM through tuning the values of a and b. This is a unique and potentially fundamentally important phenomenon in a physical system described by the MNLS eauation.

关键词： Solitons