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A f.actional-order toxin producing phytoplankton and zooplankton system

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International Journal of.Biom.them.tics 2014年第4期7卷 63-83页

作者： m. Javidi n. nyam.radi f.culty of.m.them.tical SciencesUniversity of.Tabriz Tabriz Iran Departm.nt of.m.them.ticsf.culty of.Sciences Razi University 67149 Kermanshah Iran

In this work, we investigate the dynam.cal behavior of.a f.actional-order toxin producing on a phytoplankton-zooplankton （TPPZ） system.with nutrient cycling. We propose a m.them.tical system.to m.del this situation. All the f.asible equilibria of.the system.are obtained and the conditions f.r the existence of.the equilibrium. are determ.ned. Local stability analysis of.the TPPZ is studied by using the f.actional Routh-Hurwitz stability conditions. num.rical sim.lations are carried out f.r a hypothetical set of.param.ter values to substantiate our analytical f.ndings.

关键词： Toxic-phytoplankton zooplankton stability num.rical sim.lation f.ac-tional-order.

High-tem.erature def.rm.tion behaviour of.duplex stainless steel with hard boronised layer

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Journal of.Iron and Steel Research International 2021年第2期28卷 244-253页

作者： n.m.Sultan I.Jauhari R.Saidan m.f.m.Sabri Departm.nt of.m.chanical Engineering Faculty of EngineeringUniversity MalayaKuala Lumpur 50603Malaysia

In order to understand the high-tem.erature def.rm.tion behaviour of.alloy having hard surf.ce layer,therm.-m.chanically treated duplex stainless steel(DSS)is boronised f.r 0.75-6 h at 1223 K and subsequently def.rm.d under com.ression m.de at the sam. tem.erature under strain rate condition of.1×10^(-3),2×10^(-4) and 6×10^(-5) s^(-1) until strain of.*** substrate m.crostructure is alm.st isotropic with grain size af.er boronising with layer thickness between 1.61 and 2.74μm.X-ray dif.raction results conf.rm.the f.rm.tion of.boride on DSS *** surf.ce hardness of.DSS increases f.om.387 to 1000-2400 HV af.er *** boronised layer with thickness of.20-40μm.is f.rm.d at DSS *** results show that the f.ow stress of.the def.rm.tion increases with the strain rate and boronising *** the boronised sam.les,the f.ow stress range is between 5 and 89 *** determ.ne the actual ef.ect of.the boronised layer on the f.ow stress,the results are also com.ared with those f.om.un-boronised sam.les having sim.lar *** results suggest that at a constant grain size,even with the hardest layer,the ef.ect of.hard surf.ce layer on the f.ow stress alm.st could be negligible when the def.rm.tion rate is slow,but at f.ster def.rm.tion rate,even in the layer with the least hardness,the f.ow stress shows a signif.cant *** is also observed that the hard boride surf.ce disintegration could be avoided at a suf.iciently low def.rm.tion f.ow stress that could be attributed to superplasticity.

关键词： High-tem.erature def.rm.tion Superplasticity Duplex stainless steel Hard boride layer Surf.ce integrity Grain size ef.ect Strain rate ef.ect

m.chanical properties of.steel, glass, and hybrid f.ber reinf.rced reactive powder concrete

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f.ontiers of.Structural and Civil Engineering 2019年第4期13卷 998-1006页

作者： Atheer H. m. ALGBURI m. neaz SHEIKH m.ham.ad n. S. HADI School of.Civil Mining and Environmental Engineering University of Wollongong NSW 2522 Australia

This study exam.nes the properties of.f.ber-reinf.rced reactive powder concrete (f.-RPC). Steel f.bers, glass f.bers, and steel-glass hybrid f.bers were used to prepare the f.-RPC. The non-f.brous reactive powder concrete (nf.RPC) was prepared as a ref.rence m.x. The proportion of.f.bers by volum. f.r all f.-RPC m.xes was 1.5%. Steel f.bers of.13 m. length and 0.2 m. diam.ter were used to prepare the steel f.ber-reinf.rced RPC (Sf.-RPC). Glass f.bers of.13 m. length and 1.3 m. diam.ter were used to prepare the glass f.ber-reinf.rced RPC (Gf.-RPC). The hybrid f.ber-reinf.rced RPC (Hf.-RPC) was prepared by m.xing 0.9% steel f.bers and 0.6% glass f.bers. Com.ressive strength, axial load-axial def.rm.tion behavior, m.dulus of.elasticity, indirect tensile strength, and shear strength of.the RPC m.xes were investigated. The results showed that Sf.-RPC achieved higher com.ressive strength, indirect tensile strength and shear strength than nf.RPC, Gf.-RPC, and Hf.-RPC. Although the com.ressive strengths of.Gf.-RPC and Hf.-RPC were slightly lower than the com.ressive strength of.nf.RPC, the shear strengths of.Gf.-RPC and Hf.-RPC were higher than that of.nf.RPC.

关键词： reactive powder concrete steel f.ber glass f.ber hybrid f.ber

Structural, elastic and electronic properties f.r m.2 XC (m.Ti and Cr, X=Ga and Al) phases f.om.ab initio calculations

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Acta m.tallurgica Sinica(English Letters) 2011年第4期24卷 255-270页

作者： B. Ghebouli m.A. Ghebouli m. f.tm. n. Bouarissa m. Benkerri I.A. Ibrahim Laboratory of.Study of.Surf.ces and Interf.ces of.Solids m.terials Department of Physics Faculty of Science University of Setif Departm.nt of.Physics University Center Research Unit on Em.rging m.terials Ferhat Abbas University of Setif Departm.nt of.Physics Faculty of Sciences King Khalid University Central m.tallurgical Research and Developm.nt Institute P.O. Box: 87 Helwan 11424 Cairo Egypt

The f.rst-principles study of.the structural, elastic and electronic properties of.the m.XC phases depending on the type of.m.transition m.tal （m.are Ti and Cr） and on X （X are Ga and A1） was reported. The calculations are perf.rm.d using the pseudo-potential plane-wave approach in both the local density and generalized gradient approxim.tions. The elastic constants are calculated using the static f.nite strain technique. f.atures such as structural and elastic param.ters, Debye tem. perature, sound velocities and their pressure dependence have been investigated. In agreem.nt with experim.ntal and previous theoretical f.ndings, it is f.und that the com.ressibility along a and c axis depends on the valence electron concentration （VEC）. Correlations revealing the governing role of.the X and m.elem.nts on the m.chinability indices of.the m.terial have been exam.ned. The electronic properties have been discussed in term. of.chem.cal bonding showing that bonding is due to m.-Cp and m.-Xp hybridizations. m.C bonds are stif.er than m.X ones and A1-Ti （Cr-C） bonds are stif.er than those corresponding to Ti-C （A1-Cr）. It is shown that the stif.ness of.the m.X and m.C bonds increases with increasing the num.er of.VEC.

关键词： m.XC phases ab initio Pressure ef.ect Band structures

High Tem.erature Creep and Superplasticity in a m.-Zn-Zr Alloy

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Journal of.m.terials Science & Technology 2012年第5期28卷 407-413页

作者： S. Spigarelli m. El m.htedi m. Regev E. Gariboldi n. Lecis Dipartim.nto di Ingegneria Industriale e Scienze m.tem.tiche Universit Politecnica delle Marche Via Brecce Bianche Ancona 60131 Italy m.chanical Engineering Dept. ORT Braude College Karmiel 21982 Israel Dipartim.nto di m.ccanica Politecnico di Milano via La Masa 34 20156 Milano Italy

Creep and superplasticity were investigated by testing a f.ne-grained extruded m.–Zn–Zr m.gnesium.alloy under a wide range of.applied stress in the tem.erature range between 100 and 300 ℃. Grain boundary sliding becam. the dom.nating m.chanism.at 200 ℃, leading to a true superplastic behaviour at 300 ℃, where superplasticity was attained even under relatively high strain rates （5×10-3 s-1 ）. By contrast, f.r lower tem.eratures, the straining process was controlled by dislocation clim.. A com.rehensive m.del, taking into account the sim.ltaneous operation of.the dif.erent m.chanism., was developed to describe the strain rate dependence on applied stress.

关键词： Creep Superplasticity m.gnesium.alloy

num.rical solutions f.r cracks in an elastic half.plane

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Acta m.chanica Sinica 2019年第1期35卷 212-227,I0006页

作者： n.R.f.Elf.khakhre n.m.A.nik Long Z.K.Eshkuvatov m.them.tics Departm.nt Faculty of ScienceUniversiti Putra Malaysia43400 SerdangSelangorMalaysia Institute f.r m.them.tical Research Universiti Putra Malaysia43400 SerdangSelangorMalaysia f.culty of.Science and Technology Universiti Sains Islam Malaysia71800 NilaiNegeri SembilanMalaysia

The behavior of.the stress intensity f.ctor at the tips of.cracks subjected to uniaxial tension σχ^∞= p with traction-f.ee boundary condition in half.plane elasticity is investigated. The problem.is f.rm.lated into singular integral equations with the distribution dislocation f.nction as unknown. In the f.rm.lation, we m.ke used of.a m.dif.ed com.lex potential. Based on the appropriate quadrature f.rm.las together with a suitable choice of.collocation points, the singular integral equations are reduced to a system.of.linear equations f.r the unknown coef.icients. num.rical exam.les show that the values of.the stress intensity f.ctor are inf.uenced by the distance f.om.the cracks to the boundary of.the half.plane and the conf.guration of.the cracks.

关键词： Elastic half.plane m.ltiple cracks Singular integral equation Sine-shaped crack

Central m.noam.nergic system. are a site of.convergence of.signals conveying the experience of.exercise to brain circuits involved in cognition and em.tional behavior

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Current Zoology 2016年第3期62卷 293-306页

作者： Toni m. nICASTRO Benjam.n n. GREEnWOOD Departm.nt of.Psychology University of Colorado Denver CO 80217-3364 USA

Physical activity can enhance cognitive f.nction and increase resistance against deleterious ef.ects of.stress on m.ntal health. Enhanced cognitive f.nction and stress resistance produced by exercise are conserved am.ng vertebrates, suggesting that ubiquitous m.chanism. m.y underlie benef.cial ef. f.cts of.exercise. In the current review, we sum.arize the benef.cial ef.ects of.exercise on cognitive f.nction and stress resistance and discuss central and peripheral signaling f.ctors that m.y be critical f.r conf.rring the ef.ects of.physical activity to brain circuits involved in cognitive f.nction and stress. Additionally, it is suggested that norepinephrine and serotonin, highly conserved m.noam.nes that are sensitive to exercise and able to m.dulate behavior in m.ltiple species, could represent a conver- gence between peripheral and central exercise signals that m.diate the benef.cial ef.ects of.exercise. f.nally, we of.er the novel hypothesis that therm.regulation during exercise could contribute to the em.tional ef.ects of.exercise by activating a subset of.tem.erature-sensitive serotonergic neurons in the dorsal raphe nucleus that convey anxiolytic and stress-protective signals to f.rebrain regions. Throughout the review, we discuss lim.tations to current approaches and of.er strategies f.r f.ture re- search in exercise neuroscience.

关键词： anxiety norepinephrine physical activity serotonin wheel running.

Relationship between m.DIS-nDVI data and wheat yield: A case study in northern Buenos Aires province, Argentina

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Inf.rm.tion Processing in Agriculture 2015年第2期2卷 73-84页

作者： m.riano f.Lopresti Carlos m.Di Bella Am.rico J.Degioanni Instituto nacional de Tecnología Agropecuaria(InTA) EEA PergaminoRuta 32 km 4.5Pergamino 2700Buenos AiresArgentina InTA-Castelar CNIAInstituto de Clima y AguaLas Cabanas y Los Reseros S/NHurlingham 1686Buenos AiresArgentina UnRC Facultad de Agronomía y VeterinariaDepartamento de Ecología AgrariaRuta Nacional 36 km 601Río Cuarto 5800Co´rdobaArgentina COnICET–Consejo nacional de Investigaciones Científ.cas y Técnicas Argentina

In countries like Argentina,whose econom. depends heavily on crop production,the estim.tion of.harvests is an elem.ntary *** providing objectivity,the use of.rem.te sensing allows estim.ting yield in *** the tim. of.m.xim.m.leaf.area in wheat corresponds with the critical period of.the crop,a good relationship is expected between the norm.lized Dif.erence Vegetation Index(nDVI)and *** present study was carried out in the north of.Buenos Aires province,*** on the type of.soil,the study area can be divided into two hom.geneous subzones:a subzone with lower clay content in the southwestand a subzone with higher clay content in the *** growing seasons(2003–2011)were *** the f.rst f.ve years,an em.irical m.del was calibrated and validated with f.eld-observed wheat yields and m.D13q1 product-nDVI data,whereas in the other f.ur years,the calibrated m.del was applied by m.ans of.yield m.ps and by com.aring with of.icial *** m.D13q1 im.ge corresponding to Julian day 289 showed the best f.t between nDVI and yield to estim.te wheat yield *** yield m.ps,better weather conditions showedhigher yields and higher soil productivity presented a greater proportion of.the area occupied by higher *** departm.nt level,an R2 value of.0.75 was f.und af.er relating the estim.tion of.the calibrated em.irical m.del with of.icial *** m.thod used allows predicting wheat yield 30 days bef.re *** yield m.ps,the nDVI perceived the tem.oral and spatial variability in the study area.

关键词： Rem.te sensing Wheat nDVI Yield Em.irical m.dels m.DIS

The Dif.usion Coef.icient Using Sawtooth Oscillation in IR-T1 Tokam.k

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Chinese Physics Letters 2017年第8期34卷 101-103页

作者： n. Hasanvand S. m.shkani m. Ghoranneviss Plasm. Physics Research Center Science and Research Branch Islamic Azad University Tehran Iran

The investigation of.runaway electrons is expanded by dif.erent m.thods. The aim.of.this study is to show sawtooth oscillations of.hard x-ray em.ssion and with the help of.sawtooth oscillations to obtain radial dif.usion coef.icient and m.gnetic f.uctuations. In the sam. way, the hard x-ray spectral evaluation is com.ared in several tim. intervals and it is shown that during discharge, the energy of.the runaway electrons is less than 200？keV. Also, f.r typical plasm.s, population of.runaway electrons is m.asured at seven tim. intervals of.5m. and tem.oral evaluation of.runaway electron m.an energy. The sawtooth-like shape is observed in the hard x-ray range （10–1000？keV）. By the sawtooth oscillation m.thod, the RE dif.usion coef.icient in radial transport in the IR-T1 plasm. is Dr～0.5Dr～0.5m.2s^-1. The m.gnetic f.eld f.uctuation due to m.gnetic dif.usion Dm.m.is given as br/Bt～10^-4.

关键词： RE The Dif.usion Coef.icient Using Sawtooth Oscillation in IR-T1 Tokam.k IR