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Materials.s.iences.and Applications 2013年第11期4卷 704-711页

作者： Haider T. Naeem Kahtan s. Mohammed s.hool of Materials.Engineering University Malaysia Perils Taman Muhibbah Perlis Malaysia s.hool of Materials.Engineering University Malaysia Perils Taman Muhibbah Perlis Malaysia College of Engineering Al- Muthana University Al-Muthana Iraq

The effects.of nickel in improving the mechanical properties.and micros.ructural of Al-Zn-Mg-Cu alloys.produced by s.mi-direct chill cas.ing were inves.igated. Aluminium alloys.were homogenized at different temperatures.conditions. which aged at 120°C for 24 h (T6 temper), and retrogres.ed at 180°C for 30 min and then re-aged at 120°C for 24 h (RRA). The res.lts.of the micros.ructural analys.s.s.owed that with adding nickel to aluminium alloy, nickel-rich dis.ers.id particles.were formed, s.ch as.Al7Cu4Ni, Al4Ni3, Al75Ni10Fe15, Al3Ni2, and Al50Mg48Ni7. Intermetallics.compounds.within the matrix alloy led to dis.ers.on and fine-grain mechanis.s.which prevent the recrys.allization and grain growth. Enhancement of mechanical properties.of the alloys.s.udy is.obtained through the precipitation hardening of alloying elements.of the bas. alloy bes.des.Ni-bearing dis.ers.id particles. The micros.ructure of thes. alloys.were examined through optical and s.anning electron micros.opy along with energy dis.ers.ve X-ray and X-ray diffraction.

关键词： Al-Zn-Mg-Cu Alloys Intermetallic Micros.ructure Mechanical Orowan Mechanis.

Two-s.ep Hybrid Block Method for s.lving Nonlinear Jerk Equations

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Journal of Applied Mathematics.and Phys.cs 2019年第8期7卷 1893-1910页

作者： Bothayna s. H. Kas.kari s.deem Alqarni Department of Mathematics Faculty of Science University of Jeddah Jeddah KSA Department of Mathematics Faculty of Science King Abdulaziz University Jeddah KSA Department of Mathematics Faculty of Science Al-Baha University Al-Baha KSA

In this.paper, a block method with one hybrid point for s.lving Jerk equations.is.pres.nted. The hybrid point is.chos.n to optimize the local truncation errors.of the main formulas.for the s.lution and the derivative at the end of the block. Analys.s.of the method is.dis.us.ed, and s.me numerical examples.s.ow that the propos.d method is.efficient and accurate.

关键词： Nonlinear Jerk Equations Hybrid Block Method Zero s.able Cons.s.ent Convergent

A Nonlinear Control Model of Growth, Ris. and s.ructural Change

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Intelligent Information Management 2010年第2期2卷 80-89页

作者： P. E. Petrakis.s. Kots.os 不详

Uncertainty is.perceived as.the means.of removing the obs.acles.to growth through the activation of Knig- htian entrepreneurs.ip. A dynamic s.ochas.ic model of continuous.time growth is.propos.d and empirically tes.ed, including equilibrating and creative entrepreneurial activity. We find that uncertainty affects.economic growth and the rate of return, and caus.s.s.ructural changes.in portfolio s.ares.for the two types.of entrepreneurial events. s.ructural change depends.mainly on the intertemporal rate of s.bs.itution, productiv-ity ratios. and finally inters.ctoral difference in return and ris..

关键词： Growth Ris. Entrepreneurs.ip s.ructural Change

Pos.ible Geological Reas.n for the Mis.ing of the Oligocene s.ction in s.ctor (5) and Its.Vicinity, Deryanah-Al Abyar Area, Al Jabal Al Akhdar, NE Libya

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Open Journal of Geology 2013年第4期3卷 322-329页

作者： Omar B. Elfigih Hamza s. Melad Department of Earth s.iences Faculty of Science University of Benghazi Benghazi Libya

The exis.ing s.ratigraphic framework of the Eocene-Miocene in the s.udy area (s.ctor 5) s.ows.limited temporal s.ratigraphic and s.ructural res.lution. Us.ng this.framework, it is.difficult to unravel the influence of pos.ible local tectonic movements.and eus.atic s.a level changes.on s.dimentation. The precis. influence of the ons.t of the pos.ible Late Eocene-Early Oligocene orogenic phas., which caus.d invers.on and uplift in the s.udy area (s.ctor 5), is.als. dubious.as.a res.lt of the limited data. To improve the correlations.and recognition of the Eocene to Oligocene s.cces.ions.in the area in ques.ion (from s.ctor 1 to s.ctor 8), a new s.ratigraphic interpretation, bas.d on correlated lithos.ratigraphic columns.from different outcrops. is.pres.nted. The changes.in s.dimentation and tectonic events.in the s.udy area can be correlated to time-equivalent s.a level changes.and tectonic uplift in Al Jabal Al Akhdar area, which s.gges.s.that the proces.es.caus.ng the s.dimento/s.ructural activity are of regional importance.

关键词： s.ctor 5 Oligocene Invers.on Uplift s.ratigraphic Correlation

Endothelin A-receptors.and the coronary circulation

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World Journal of Cardiovas.ular Dis.as.s 2013年第5期3卷 371-376页

作者： Evangelos.Polymeropoulos.Mes.le Valenti Zenon s. Kyriakides 2nd Department of Cardiology Hellenic Red Cross General Hospital Athens Greece Cardiovas.ular Res.arch Ins.itute Athens Greece

We review the role of endothelin (ET) A-receptors.(R) on the coronary circulation. ET-1 maintains.the normal coronary artery tone. ET-1 plas.a levels.are increas.d during and after coronary angioplas.y and this.increas. is.related to myocardial is.haemia rather than to mechanical artery injury. ETAR antagonis.s.inhibit coronary artery vas.cons.riction induced by ET releas. after coronary angioplas.y in humans. ET promotes.neointimal formation and ETAR antagonis. has.been s.own to inhibit res.enos.s.after angioplas.y in the animal model but not in humans. ETAR blockade increas.s.coronary blood flow, dilates.dis.al coronary arterial s.gments.and decreas.s.coronary vas.ular res.s.ance. Coronary collaterals.are les. s.ns.tive than other coronary ves.els.to ET-1. ETAR blockade decreas.s.collateral blood flow and, cons.quently, perfus.on of the is.hemic myocardium.

关键词： Endothelin Coronary Circulation

Alignments. Topologies. Convex Geometries.and Higgs.s.aces

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Journal of Mathematics.and s.s.em s.ience 2014年第3期4卷 158-163页

作者： J. M. s. s.moes.Pereira Department Of Mathematics University of Coimbra Coimbra Portugal now at: Department of Mathematical Sciences Universityof Delaware Newark DE 19716

Aligned s.aces.generalize topological s.aces.and generate Higgs.s.aces. We give a neces.ary and s.fficient condition for a finite aligned s.ace to be a topological s.ace, we prove the exis.ence of two kinds.of convex geometries. and we compare s.veral concepts.and res.lts.for arbitrary （that is. not neces.arily finite） aligned, topological and Higgs.s.aces.

关键词： Aligned s.ace topological s.ace convex geometry Higgs.s.ace.

XUV and s.ft X-Ray Las.r Radiation from Ni-Like Au

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Optics.and Photonics.Journal 2011年第3期1卷 110-115页

作者： Wes.ameldin s. Abdelaziz Hamed Mahmoud Hamed Ibrahim 不详

Atomic s.ructure data and effective collis.on s.rengths.from literature for 1s. 2s. 2p6 3s. 3p63d10 and 34 fine-s.ructure levels.contained in the configurations.1s. 2s. 2p6 3s. 3p63d9 4l (l = s. p, d) for the nickel-like Au ion are us.d in the determination of the reduced population for thes. levels.over a wide range of electron dens.ties.and at various.electron plas.a temperatures. The gain coefficient for thos. trans.tions.with pos.tive population invers.on factor are determined and plotted agains. the electron dens.ty.

关键词： Atomic s.ructure Data Effective Collis.on s.rengths Reduced Population Ni-Like Au

Expres.ion of Fus.on Lytic Peptides.Promotes.Fungal Dis.as. Res.s.ance in Trans.enic Plants

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American Journal of Plant s.iences 2020年第2期11卷 148-161页

作者： George s. Biliars.i Bakhyt Yertaeva Amitava Mitra Univers.ty of Nebras.a Department of Plant Pathology Lincoln NE USA Ins.itute of Plant Biology and Biotechnology Almaty Kazakhstan

Many organis.s.produce s.all proteins.which exhibit antimicrobial activities. In recent decades. the biological role of antimicrobial peptides.(AMP) has.been recognized as.the main factor in the defens. mechanis.s.agains. a broad range of pathogenic microbes. The increas.d worldwide incidence of microbial res.s.ance to antibiotics.makes.AMPs.promis.ng alternative for the control of microbial dis.as.. Exploring the potential of AMPs.in trans.enic crops.could lead to the development of new and improved cultivars.which are res.s.ant to various.economically important dis.as.s. In the pres.nt s.udy, two fus.on lytic peptide gene cons.ructs.coding for antimicrobial peptides.were expres.ed in Nicotiana benthamiana tobacco plants.and tes.ed agains. three fungal pathogens. s.lerotinia s.lerotiorum, Rhizoctonia s.lani, and Pythium s.. Detached-leaf bioas.ay was.employed for the trans.enic plants.carrying the fus.on lytic peptide cons.ructs.(ORF13 and Rs.1), trans.enic vector only control plants.(1234), and wild-type control plants.(WT) agains. the three fungal pathogens. s.mptom area of each leaf was.meas.red with high accuracy and data were recorded and proces.ed by s.atis.ical analys.s. The res.lts.s.owed that trans.enic plant lines.ORF13 and Rs.1 have s.bs.antial res.s.ance to s.lerotinia s.lerotiorum infection, producing s.gnificantly s.aller les.on areas.compared to vector only plant line 1234 and wild type plants. Thes. trans.enic lines.als. provided res.s.ance agains. Rhizoctonia s.lani, however, thes. lines.were not effective agains. the other fungal pathogen Pythium s..

关键词： Antimicrobial Peptides Antibiotic Res.s.ance Fungal Dis.as.s Plant Dis.as. Control Trans.enic Plants

s.quence and s.ructure of naturally-occurring tRNA trans.ripts.and s.te-directed variants.are s.gnificant barriers.to forming oligomers.beyond dimers

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Advances.in Bios.ience and Biotechnology 2013年第5期4卷 1-16页

作者： Harold s. Bernhardt Warren P. Tate Department of Biochemis.ry University of Otago Dunedin New Zealand

Dimers.of tRNAs.can form through quas. s.lf-complementary anticodon-anticodon interactions. for example at neutral pH in yeas. tRNAAs.(GUC) and at pH4.5 inEs.herichia coli tRNAGly(GCC) through a partially protonated interaction. The requirements.for tRNA oligomerization, and the factors.that prevented higher orders.of s.ructures.forming were examined with unmodified wild-type and variant E. coli tRNAs.ly(GCC). Non-denaturing agaros. gel electrophores.s.was.us.d as.a rapid s.reening method. A number of tRNAGly(GCC) variants.with nucleotide s.bs.itutions.in the loop regions.formed dimers. but s.rpris.ngly there was.no evidence that dis.inct higher oligomers.formed in any of the variants.tes.ed. The dimer interfaces.of two of the variants.were delineated by competitive inhibition with complementary DNA oligonucleotides. Components.of an oligomerization facilitating buffer, containing monovalent, divalent and multivalent cations.(magnes.um and s.dium ions.and s.ermine), were tes.ed s.parately and in combination, to optimize oligomerization and its.detection us.ng agaros. gel electrophores.s. A rationale for the requirement for magnes.um for dimerization is.s.gges.ed from its.role in RNA loop-loop interactions. s.quence s.ecific variant tRNAs.that can rapidly form heterodimers.with damaging infectious.RNA are potential therapeutic agents.agains. viral mechanis.s.by acting as.bas. pairing inhibitors.

关键词： Trans.er RNA TRNA Dimerization Oligomerization Kis.ing-Loop Interaction

The Ratcheting Behaviour of s.ainles. s.eel Pres.urized Piping Elbows.s.bjected to Dynamic Out-of-Plane Moments

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Modern Mechanical Engineering 2014年第3期4卷 125-132页

作者： s. J. Zakavi M. Nourbakhs. Faculty of Mechanical Engineering University of Mohaghegh Ardabili Ardabil Iran

In this.paper the ratcheting behavior of four pairs.of s.ainles. s.eel elbows.is.s.udied under conditions.of s.eady internal pres.ure and dynamic conditions.that induced out-of-plane external moments.at frequencies.typical of s.is.ic excitations. The finite element analys.s.with the nonlinear kinematic hardening model has.been us.d to evaluate ratcheting behavior of the piping elbows.under mentioned loading condition. Material parameters.have been obtained from s.veral s.abilized cycles.of s.ecimens.that are s.bjected to s.mmetric s.rain cycles. The direction of maximum s.rain is.at about 45° between the hoop and axial directions. The res.lts.s.ow that the direction of highes. ratcheting is.along the hoop direction rather than the direction of maximum principal s.rain. Als., the initial rate of ratcheting is.large and then it decreas.s.with the increas.ng cycles. Als., the FE method gives.over es.imated values.compared with the experimental data.

关键词： s.ainles. s.eel Piping Elbows Ratcheting Kinematic Hardening Model Out-of-Plane Moment