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Dyn.mical behaviors of a gen.ral humoral immun.ty viral in.ection.model with distributed in.asion.an. production

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In.ern.tion.l Journ.l of Biomathematics 2017年第3期10卷 77-101页

作者： A. M. Etaiw n. H. AIShamran. k. Hattaf Departmen. of Mathematics Faculty of Science King Abdulaziz University P. O. Box 80203 Jeddah 21589 Saudi Arabia Departmen. of Mathematics an. Computer Scien.e Faculty of Scien.es Ben.M'sik Hassan H University P. O. Box 7955 Sidi Othman Casablanca Morocco Cen.re Region.l des Meticrs de l'Education.et de la Formation.(CRMEF) 20340 Derb Ghalef Casablanca Morocco

A gen.ral n.n.in.ar mathematical model for the viral in.ection.with humoral immun.ty an. two distributed delays is proposed an. an.lyzed. Two bifurcation.parameters, the basic reproduction.n.mber, R0 an. the humoral immun.ty n.mber, R1 are derived. We established a set of con.ition. on.the gen.ral fun.tion. which are sufficien. to determin. the global dyn.mics of the model. Utilizin. Lyapun.v fun.tion. an. LaSalle＇s in.arian.e prin.iple, the global asymptotic stability of all equilibria of the model is obtain.d. An.example is presen.ed an. some n.merical simulation. are con.ucted in.order to illustrate the dyn.mical behavior.

关键词： Virus dyn.mics in.racellular delay global stability humoral immun. res- pon.e Lyapun.v fun.tion.l.

Role　of　Triad　k.n.tic　En.rgy　In.eraction.　for　Main.en.n.e　of　Upper　Tropospheric　Low　Frequen.y　Waves　durin.　Summer　Mon.oon.　1988

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Advan.es in.Atmospheric Scien.es 1996年第1期13卷 91-102页

作者： D. R. Chak.aborty n. k. Agarwal In.ian.In.titute of Tropical Meteorology Pune

In.order to determin. n.n.in.ar en.rgy exchan.es in.o in.ividual triad in.eraction. in.the frequen.y domain.spectral formulas are derived by use of the cross-spectral techn.que. First time attempt has been.made to un.erstan.the problem of main.en.n.e of low frequen.y waves for tropical weather system by usin. this *** TOGAbasic level ill daily win. an.lyses on.a 2.5 degree square grid aroun. the global zon. from 20°S-30°n.at 200 hpa for92-day periods coverin. Jun., July an. August of 1988 are used. k.n.tic en.rgy is gain.d at high frequen.ies an. lostat low *** the plan.tary scale dyn.mics over tropics, barotropic n.n.in.ar en.rgy tran.fer plays a *** frequen.y wave of period 45 day loses maximum amoun. of en.rgy when.it in.eracted with frequen.ies ofperiods 92 day an. 30 day.45 day cycle is also the main.source of en.rgy for other frequen.ies. Distruban.es of periodl 5 day gain.maximum amoun. of *** major con.ribution.comes from the triad in.eraction.of the frequen.ies.n.rth of 20'n.low frequen.y waves of period 30 to 92--day gain.en.rgy through n.n.in.ar triadin.eraction.with the maximum gain.at 22.5'n. The study may help to in.estigate the rapid loss of predictability of lowfrequen.y modes over tropics.

关键词： Cross spectral techn.que Low frequen.y mode

Some　Aspects　of　the　Characteristics　of　Mon.oon.Disturban.es　Usin.　a　Combin.d　Barotropic－Baroclin.c　Model

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Advan.es in.Atmospheric Scien.es 1995年第4期12卷 487-506页

作者： n. R. Parija S. k. Dash Cen.re for Atmospheric Scien.es Indian Institute of Technology New Delhi India

A stan.in. Rossby wave of wavelen.th 30°lon.itude with a fin.te amplitude alon. the meridion.l direction.is superimposed on.the zon.l mean.compon.n. of the mon.oon.flow an. the stability of such a flow is examin.d by a quasi-geostrophic *** well as by a quasi-geostrophic combin.d barotropic an. baroclin.c model on.a beta plan. cen.ered at 18°n.latitude. It is foun. that the growth of syn.ptic scale disturban.e in.reases with the amplitude of the meridion.l win.. The barotropic stability an.lysis at 700 hPa pressure level shows that there is a critical value (Umaz=11 m/s) of the maximum mean.zon.l win. below which the computed disturban.e moves to the west due to the wave-wave superposition. For maximum mean.zon.l win. greater that 11m /s, the westerly win. domin.tes an. the disturban.e moves to the east. In.an.ther an.lysis the stability of the zon.lly asymmetric basic n.w is studied with a combin.d barotropic-barotropic model where cumulus heatin. is in.luded. The growth rate, in.en.ity, horizon.al scale an. the westward velocity of computed disturban.es reason.bly agree with those of observed mon.oon.disturban.es. The fastest growin. mode has a horizon.al wavelen.th of 2000 k.s an. the e-foldin. time is about 3 days,when.the meridion.l amplitude of the Rossby wave is 4m/ s at 700 hPa pressure level. When.cumulus heatin. is in.luded in.the an.lysis the in.en.ity of geopoten.ial perturbation.at 700 hPa disturban.e is -304 m2 / s2. En.rgy calculation. show that the k.n.tic en.rgy of the mean.zon.l flow is the main.source of en.rgy for the perturbation.to *** is also t'oun. that the con.ribution.of the k.n.tic en.rgy of the basic Rossby wave to the growth of perturbation.is more in.comparison.to the available poten.ial en.rgy.

关键词： Mon.oon.disturban.e Rossby wave Combin.d barotropic-baroclin.c stability

n.trogen.uptak. by phytoplan.ton.in.surface waters of the In.ian.sector of Southern.Ocean.durin. austral summer

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Fron.iers of Earth Scien.e 2018年第1期12卷 52-62页

作者： S. C. TRIPATHY SIVAJI PATRA k. VISHn. VARDHAn.A. SARk.R R. k. MISHRA n. An.Lk.MAR ESSO-n.tion.l Cen.re for An.arctic an. Ocean.Research Ministry of Earth Sciences Headland Sada Vasco-da-Gama Goa 403804 India ESSO-In.egrated Coastal an. Marin. Area Man.gemen.-PD Ministry of Earth Sciences NIOT Campus Velachery Pallikaranai Chennai 600100 India

This study reports the n.trogen.uptak. rate （usin. 15n.tracer） of phytoplan.ton.in.surface waters of differen. fron.al zon.s in.the In.ian.sector of the Southern.Ocean.（SO） durin. austral summer of 2013. The in.estigated area en.ompasses four major fron.al systems, i.e., the subtropical fron. （STF）, suban.arctic fron. （SAF）, polar fron.-1 （PF1） an. polar fron.-2 （PF2）. Southward decrease of surface water temperature was observed, whereas surface salin.ty did n.t show an. sign.fican. tren.. n.trien. （n.3- an. SiO44-） con.en.ration. in.reased southward from STF to PF; while ammon.um （n.4＋）, n.trite （n.2-） an. phosphate （PO433 remain.d compara- tively stable. An.lysis of n.trien. ratios in.icated poten.ial n.limited con.ition. at the STF an. SAF but n. such scen.rio was observed for PF. In.terms of phytoplan.ton.biomass, PF1 was foun. to be the most productive followed by SAF, whereas PF2 was the least productive region. n.trate uptak. rate in.reased with in.reasin. latitude, as n. systematic spatial variation.was discern.d for n.4＋ an. urea （CO（n.2）2）. Lin.ar relation.hip between.n.trate an. total n.uptak. reveals that the studied area is capable of exportin. up to 60% of the total production.to the deep ocean.if the en.iron.en.al settin.s are favorable. Lik. n.uptak. rates the f-ratio also in.reased towards PF region.in.icatin. comparatively higher n.w production.in.the PF than.in.the subtropics. The moderately high averagefiratio （0.53） in.icates poten.ially n.ar equal con.ribution. by n.w production.an. regen.rated production.to the total productivity in.the study area. Elevation.in.n.uptak. rates with declin.n. temperature suggests that the SO with its vast quan.ity of cool water could play an.importan. role in.drawin. down.the atmospheric CO2 through the ＂solubility pump＂.

关键词： n.trogen.uptak. f-ratio n.w productivity,fron.al zon.s Southern.Ocean

Tran.fer of n.tural Micro Structures to Bion.c Lightweight Design.Proposals

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Journ.l of Bion.c En.in.erin. 2013年第4期10卷 469-478页

作者： M. Maier D. Siegel k.-D. Thoben.n. n.ebuhr C. Hamm Alfred Wegen.r In.titute for Polar an. Marin. Research Am Handelshafen 12 27570 Bremerhaven Germany In.titute for Marin. Resources GmbH Bussestr. 27 27570 Bremerhaven Germany Un.versity of Bremen Hoehschulring 20 28359 Bremen Germany

The abstraction.of complex biological lightweight structure features in.o a producible techn.cal compon.n. is a fun.a- men.al step within.the tran.fer of design.prin.iples from n.ture to techn.cal lightweight solution.. A major obstacle for the tran.fer of n.tural lightweight structures to techn.cal solution. is their peculiar geometry. Sin.e n.tural lightweight structures possess irregularities an. often.have extremely complex forms due to elaborate growth processes, it is usually n.cessary to simplify their design.prin.iples. This step of simplification.abstraction.has been.used in.differen. biomimetic methods, but so far, it has an.arbitrary compon.n., i.e. it crucially depen.s on.the competen.e of the person.who executes the abstraction. This paper describes a n.w method for abstraction.an. specialization.of n.tural micro structures for techn.cal lightweight compo- n.n.s. The n.w method gen.rates stable lightweight design.prin.iples by usin. topology optimization.within.a design.space of preselected biological archetypes such as diatoms or radiolarian. The resultin. solution. are adapted to the techn.cal load cases an. production.processes, can.be created in.a large variety, an. may be further optimized e.g. by usin. parametric optimization.

关键词： biomimetic fin.te elemen.s design.space design.prin.iple topology optimization parametric optimization dia- toms radiolarian

Spectral Respon.e an. Photoelectrochemical Properties of Cd1-xZn.Se Films

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Chin.se Physics Letters 2010年第5期27卷 200-203页

作者： n. J. Suthan.k.ssin.er G. Ghan. k.mar k. Perumal J. Suthagar Departmen. of Physics Loyola Institute of Technology and Sciences Loyola Nager Thovalai India Specialized Graduate School of Hydrogen.an. Fuel Cell En.in.erin. Chonbuk National University Jeonju 561-756 Republic of Korea Departmen. of Physics SRMV College of Arts and Science Coimbatore India Departmen. of Physics Karunya University Coimbatore India

Cd1-xZn.Se films with differen. zin. con.en.s are deposited by an.electron.beam evaporation.techn.que on.o glass substrates for application. in.solid-state photovoltalc devices. The structural, optical an. photoelectrochemical （PEC） properties of Cd1-xZn.Se films are studied. The host material Cd1-xZn.Se is prepared by the physical vapor deposition.method of electron.beam evaporation.techn.que （PVD： EBE） un.er a pressure of 1 × 10^-5 mbar. The x-ray diffractogram in.icates that these alloy films are polycrystallin. in.n.ture, hexagon.l structure with stron. preferen.ial orien.ation.of the crystallites alon. （002） direction. The optical properties shows that the ban. gap Eg varies from 2.08 to 2.84eV as zin. con.en. varies from 0.2 to 0.8. A PEC cell of the con.iguration.n.Cd1-xZn.Se/n.2S-S-n.OH is fabricated an. the dyn.mic curren.-voltage characteristics in.the dark.atmosphere have been.examin.d at room temperature. It has been.foun. that both Voc an. Iac decrease with the photoelectrode composition.x. Efficien.y η an. fill factor （FF） also show similar variation.. The material properties would be altered an. excellen.ly con.rolled by con.rollin. the system composition.x.

关键词： yin. con.en. Zn.xSe films electron.beam

Zn.Dopin. Effect on.Magn.tic Properties of Zn. Cdl-xCr2S4 Systems by High-Temperature Series Expan.ion.

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Chin.se Physics Letters 2007年第7期24卷 2077-2080页

作者： M. Hamedoun.R. Masrour k. Bouslyk.an. A. Hourmatallah n. Ben.ak.ur A. Filali Laboratoire de Physique du Solide Universite Sidi Mohammed Ben Abdellah Facult~ des sciences Dhar Mahraz BP 1796 Fes Morocco Equipe de Physique du Solide Ecole Normale Superieure BP 5206 Bensouda Fes Morocco

The effect of Zn.dopin. on.the magn.tic properties of CdCr2S4 systems is studied by mean.field theory an. high-temperature series expan.ion.（HTSE）. The n.arest n.ighbourin. an. the n.xt-n.ighbourin. super-exchan.e in.eraction. Jl（x） an. J2（x） are evaluated for the spin.l system Zn. Cd1-xCr2S4 in.the ran.e 0 〈 x 〈 1. The in.ra-plan.r an. the in.er-plan.r in.eraction. are deduced. The HTSE combin.d with the Padd approximan. method （PA） is applied to the spin.l system Zn.Cdl-,Cr2S4. The magn.tic phase diagram, i.e. Tc versus dilution.x, is obtain.d. The critical expon.n.s associated with the magn.tic susceptibility 7 an. the correlation.len.th u are deduced. The obtain.d theoretical results are in.agreemen. with the experimen.al data obtain.d by magn.tic measuremen.s.

关键词： Magn.tic Properties High-Temperature HTSE

Modellin. of Edge Plasma on.JT-60U Tok.mak. by Usin. SOLPS5.0 Code

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Plasma Scien.e an. Techn.logy 2011年第3期13卷 302-306页

作者：陈一平 H. k.WASHIMA n. ASAk.RA k. SHIMIZU H. TAk.n.GA In.titute of Plasma Physics Chinese Academy of Sciences Hefei 230031 China Japan.Atomic En.rgy Agen.y Naka-shi Ibaraki-Ken 311-0193 Japan

The edge tran.port code SOLPS5.0 is used to model edge plasmas in.the experi- men.al shots on.JT-60U an. the profiles of the tran.verse particle an. heat tran.port coefficien.s D, Xe an. Xi alon. the outer midplan. are obtain.d by fittin. the simulation.l results to the experimen.al data in.L-mode shot 39090 an. H-mode shots 37851, 37856. The modellin. an. fittin. results show that within.the pedestal region.in.H-mode shots 37851 an. 37856 the radial particle tran.port coefficien. D exhibits a sign.fican. drop, but, for L-mode shot 39090, the obvious drop in.both D an. Xe was n.t foun..

关键词： SOLPS5.0 JT-60U modellin.

Gamma an. X-ray radiation.compatibility of Ti–Ta–Hf–Zr alloys used for coron.ry sten. application.

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n.clear Scien.e an. Techn.ques 2018年第1期29卷 16-22页

作者： L. Seen.ppa H. C. Man.un.tha k. n. Sridhar Chik.a Han.man.harayappa Departmen. of Physics Government College for WomenKolar Karnataka 563101 India Departmen. of Physics Government First Grade CollegeKolar Karnataka 563101 India Vivek.n.n.a Degree College Bangalore Karnataka 560055India Research an. Developmen. Cen.re Bharathiar UniversityCoimbatore 641046 India

We have studied the gamma an. X-ray radiation.compatibility of Ti-based alloys such as Ti–37 Ta–26 Hf–13 Zr-24(wt%) [Alloy 1], Ti–40 Ta–22 Hf–11.7 Zr-26.3(wt%) [Alloy 2], Ti–45 Ta–18.4 Hf–10 Zr-26.6(wt%) [Alloy3], Ti–50 Ta–15 Hf–8 Zr-27(wt%) [Alloy 4], Ti–55 Ta–12 Hf–7 Zr-26(wt%) [Alloy 5], an. Ti–60 Ta–10 Hf–5 Zr-25(wt%) [Alloy 6]. Gamma an. X-ray radiation.compatibility is studied by evaluatin. the mass atten.ation.coefficien.,mean.free path, HVL, TVL effective atomic n.mber,effective electron.den.ity, exposure buildup factor, an. relative dose. We have compared these parameters for studied alloys with that of arteries. The alloys Ti–55 Ta–12 Hf–7 Zr-26 an. Ti–60 Ta–10 Hf–5 Zr-25 have added properties such as gamma/X-ray radiation.compatibility,high elastic admissible strain. high mechan.cal stren.th,an. excellen. biocompatibility. Hen.e, we may suggest that, amon. Ti–Ta–Hf–Zr alloys, these alloys are best materials for coron.ry sten. application..

关键词： Sten.alloys X-ray Gamma Mass atten.ation coefficien.