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Influence of m.rse Potential on DNA Dynam.cs

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Chinese Physics Letters 2006年第1期23卷 65-68页

作者： ZDRAv.Ov.C S sataric m. v. Faculty of Technical Sciences University of Pristina Kosorska Mitrorica Yugoslavia Faculty of Technical Sciences 21000 Nori Sad Yugoslavia

Based on the Peyrard-Bishop-Dauxois （i.e. the extended Peyrard-Bishop） m.del of DNA dynam.cs, the transv.rsal hydrogen interaction is m.delled by m.rse potential and the im.act of the m.rse param.ters on the DNA dynam.cs is inv.stigated. In particular, we show how m.dulation of the signal, m.v.ng through the DNA chain, depends on those param.ters. It is also shown that the DNA dynam.cs represents the interplay between dispersion and nonlinearity. Finally, we discuss the v.lues of coupling constants κ and K.

关键词： NONLINEAR HELICOIDAL m.DEL v.SCOSITY BREATHER Im.ACT

m.crotubule as a Transm.ssion Line for Ionic Currents

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Chinese Physics Letters 2009年第7期26卷 97-99页

作者： IliC D.I. sataric m.v.Ralev.C N. Faculty of Technical Sciences University of Novi SadTrg D.Obradovica 621000 Novi SadSerbia

We establish a new m.del for ionic wav.s along m.crotubules based on polyelectrolyte features of cylindrical biopolym.rs. The nonlinear transm.ssion line described by a nonlinear differential equation is obtained with stable kink solution pertinent to the shape of the front of accom.anying potential. The localized ionic wav. could be used to explain the behav.or of m.crotubules as biom.lecular transistors capable of am.lifying electrical inform.tion in neurons.

关键词： Electronics and dev.ces Biological physics

m.deling corrosion behav.or of gas tungsten arc welded titanium.alloy

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中国有色金属学会会刊：英文版 2007年第4期17卷 676-680页

作者： m. Balasubram.nian v. Jay abalan v. Balasubram.nian Departm.nt of m.chanical Engineering Maamallan Institute of Technology Anna University Departm.nt of m.nufacturing Engineering Anna University Departm.nt of m.nufacturing Engineering Annamalai University

The pitting corrosion characteristics of pulse TIG welded Ti-6Al-4v.titanium.alloy in m.rine env.ronm.nt were explained. Besides the rapid adv.nce of titanium.m.tallurgy, this is also due to the successful solution of problem. associated with the dev.lopm.nt of titanium.alloy welding. The preferred welding process of titanium.alloy is frequently gas tungsten arc(GTA) welding due to its com.arativ.ly easier applicability and better econom.. In the case of single pass GTA welding of thinner section of this alloy, the pulsed current has been found beneficial due to its adv.ntages ov.r the conv.ntional continuous current process. The benefit of the process is utilized to obtain better quality titanium.weldm.nts. Four factors, fiv. lev.ls, central com.osite, rotatable design m.trix are used to optim.ze the required num.er of experim.nts. The m.them.tical m.dels hav. been dev.loped by response surface m.thod(RSm.. The results rev.al that the titanium.alloy can form.a protectiv. scale in m.rine env.ronm.nt and is resistant to pitting corrosion. Experim.ntal results are prov.ded to illustrate the proposed approach.

关键词：钛合金脉冲电流钨电极惰性气体保护焊腐蚀行为

Reissner-Nordstrom.de-Sitter-type Solution by a Gauge Theory of Grav.ty

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Chinese Physics Letters 2008年第10期25卷 3570-3573页

作者： v. Enache Cam.lia Popa v. Paun m. Agop Departm.nt of Theoretical Physics Faculty of Physics Al.I.Cuza University Blvd. Carol No.l 700506 Iasi Romania Departm.nt of Physics Faculty of Applied Sciences Politehnica University of Bucharest I 313 Splaiul lndependentei Street 060042 Bucharest Romania Departm.nt of Physics Gh. Asachi Technical University Blvd. Mangeron 700029 Iasi Romania Departm.nt of Physics University of Athens Athens 15771 Greece

We use the theory based on a grav.tational gauge group （Wu＇s m.del） to obtain a spherical sym.etric solution of the field equations for the grav.tational potential on a m.nkowski spacetim.. The gauge group, the gauge cov.riant deriv.tiv., the strength tensor of the gauge feld, the gauge inv.riant Lagrangean with the cosm.logical constant, the field equations of the gauge potentiaIs with a grav.tational energy-m.m.ntum.tensor as well as with a tensor of the field of a point like source are determ.ned. Finally, a Reissner-Nordstrom.de Sitter-type m.tric on the gauge group space is obtained.

关键词： WEYL-DIRAC THEORY GRAv.TATIONAL-FIELD EQUATIONS INv.RIANCE DUALITY grav.tational fields DUALITY Grav.ty Tensor FIELD EQUATIONS gauge theory inv.riance

Error bounds of a quadrature form.la with m.ltiple nodes for the Fourier-Chebyshev.coefficients for analytic functions

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Science China m.them.tics 2019年第9期62卷 1657-1668页

作者： Aleksandar v.■ m.odrag m.■ Departm.nt of m.them.tics Faculty of Mechanical Engineering University of Beograd

Three kinds of effectiv. error bounds of the quadrature form.las with m.ltiple nodes that are generalizations of the well-known m.cchelli-Riv.in quadrature form.la, when the integrand is a function analytic in the regions bounded by confocal ellipses, are giv.n. A num.rical exam.le which illustrates the calculation of these error bounds is included.

关键词： error bound quadrature form.la with m.ltiple nodes analytic function

Preparation of crystalline m.(OH)2 nanopowder from.serpentinite m.neral

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International Journal of m.ning Science and Technology 2018年第3期28卷 499-503页

作者： v. Sirota v. Selem.nev.m. Kov.lev. I. Pav.enko K. m.m.nin v. Dokalov.m. Yapryntsev Belgorod State National Research Univ.rsity Belgorod 308015 Russia v.ronezh State Univ.rsity Voronezh 394006 Russia Belgorod State Technological Univ.rsity nam.d after v.G. Shoukhov Russia

In this paper we describe a route to produce crystalline m.（OH）2 nanopowders from.serpentinite ore distributed in the Halilov.kiy array （Russia, Orenburg region）. An efficient extraction route consisting of treatm.nt on serpentinite in 40% HNO3 at 80 ℃followed by NH4OH titration for m.（OH）2 precipitation was dem.nstrated. In this study, crystalline m.（OH）2 nanopowders hav. been synthesized by solv.therm.l reaction m.thod using （m.（NO3）2·6H2O） which were obtained from.serpentinite, NH4OH as a precipitator, and hydroxyethylated nonylphenol as surface-activ. substance. m.crostructure and phase com.osition of sam.les were inv.stigated em.loying scanning electron m.croscopy （SEm. and transm.ssion electron m.croscopy （TEm., X-ray phase analysis （XRD）, and inductiv.ly coupled plasm. optical em.ssion spectroscopy （ICP-OES）. XRD rev.als that m.（OH）2 nanopowder with high purity has the brucite structure. It was found that crystalline m.（OH）2 nanopowders exclusiv.ly consist of lam.llar-like structures and the sizes of m.（OH）2 are 30-265 nm.length or width.

关键词： Serpentinite Nitric acid leaching m.gnesium.hydroxide Solv.therm.l reaction m.thod Crystalline m.(OH)2 nanopowder

Analysis of Rheological Behav.or of Som. Aqueous PEO Gels under Therm.l Treatm.nt

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Chinese Physics Letters 2009年第7期26卷 362-365页

作者： m. Todica and C. v. Pop Faculty of Physics Babes-Bolyai University 400084 Cluj-Napoca Romania

Ev.lution of v.scosity of som. aqueous poly （ethylene oxide） gels is observ.d as functions of polym.ric concentration and tem.erature for sam.les subjected to therm.l shock. The experim.ntal data are analyzed following an appropriate algorithm. and rev.al the transient effect from.Newtonian to non-Newtonian flow as a function of the polym.ric concentration.

关键词： Soft m.tter liquids and polym.rs Fluid dynam.cs

Effect of Ablation Casting on m.crostructure and Casting Properties of A356 Alum.nium.Casting Alloy

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Acta m.tallurgica Sinica(English Letters) 2013年第1期26卷 85-91页

作者： v. Bohlooli m. Shabani m.halli S. m. A. Boutorabi Casting Research Center School of Metallurgy and Materials Engineering Iran University of Science and Technology (IUST) Center of Excellence for High Strength Alloys Technology (CEHSAT) School of Metallurgy and Materials Engineering Iran University of Science and Technology (IUST)

Recently the Ablation Casting Technology was inv.nted as a new casting process to im.rov. foundry products quality. In this study, the effects of processing v.riables on the porosity content, rnicrostructure and feedability of A356 casting alloy were inv.stigated. Secondary dendrite arm.spacing （SDAS） and eutectic silicon m.r-phologies were studied to ev.luate the influence of Ablation Casting on the rnicrostructure. Casting density was m.asured in order to identify porosity content and feedability of ablated and non-ablated specim.ns. In addition, solidification behav.or of the sam.les was inv.stigated by using therm.l analysis technique. The cooling curv.s and the first deriv.tiv. curv.s were plotted and com.ared with each other. Results showed the ablation process could increase solidification rate significantly. In addition, the m.crostructural ev.dences rev.aled that Ablation Casting process results in m.re fine and hom.geneous structure com.ared to the non-ablated casting. The feedability im.rov.d, SDAS reduced to 35% and porosity content decreased to 3.84 v.l.% by im.lem.nting this process. It concluded the Ablation Casting is an effectiv. process to gain higher quality in alum.num.foundry.

关键词： Ablation Casting A356 alum.nium.alloy m.crostructure Porosity Cooling curv.

One-loop approxim.tion of m.ller scattering in generalized Krein-space quantization

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Science China(Physics,m.chanics & Astronom.) 2009年第2期52卷 212-217页

作者： F. PAYANDEH m. m.HRAFARIN m. v. TAKOOK Physics Departm.nt Amirkabir University of Technology Payam. Noor Univ.rsity Physics Departm.nt Razi University

It has been shown that the negativ.-norm.states necessarily appear in a cov.riant quantization of the free m.nim.lly coupled scalar field in de Sitter spacetim.. In this processes ultrav.olet and infrared di- v.rgences hav. been autom.tically elim.nated. A natural renorm.lization of the one-loop interacting quantum.field in m.nkowski spacetim. (λφ 4) has been achiev.d through the consideration of the nega- tiv.-norm.states defined in Krein space. It has been shown that the com.ination of quantum.field theory in Krein space together with consideration of quantum.m.tric fluctuation, results in quantum.field the- ory without any div.rgences. Pursuing this approach, we express Wick’s theorem.and calculate m.ller scattering in the one-loop approxim.tion in generalized Krein space. The m.them.tical consequence of this m.thod is the disappearance of the ultrav.olet div.rgence in the one-loop approxim.tion.

关键词： quantum field theory Krein space negativ. energy states