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Journal of Iron and Steel Research International 2013年第12期20卷 82-91页

作者： m Balakrishnan v Balasubramanian G madhusudhan Reddy Center for materials Joining and Research(CEmAJOR) Department of Manufacturing EngineeringAnnamalai University Solidification Technology Division Metal Joining GroupDefense Metallurgical Research Laboratory(DMRL)

Armour grade quenched and tempered steel closely confirming to AISI 4340 is well known for its superior ballistic performance and hence used in the fabrication of combat vehicles. The traditional fillers like austenitic stain- less steel showed poor ballistic performance of these welded joints as compared to the base metal. Attempts have been made to deposit hardfaced interlayer between austenitic stainless steel weld metals. Though this method, mar-- ginal improvements in ballistic performance can be yielded, and cracks were observed in between base metal and hardfaced layer. Thickness of the hardfaced interlayer plays a vital role for the effective ballistic performance. Thus, an attempt has been made to investigate the effect of hardfaced interlayer thickness on ballistic performance of ar- mour steel welds. The results of effect of buttering, low hydrogen ferritic （LHF） filler and three different hardfaced layer thicknesses （4, 5.5 and 7 ram） on ballistid performance of shielded metal arc welded armour steel joints were given.

关键词： armour steel low hydrogen ferritic electrode sandwich structure ballistic performance hardfacing metallography

Efficient Load Balancing with mANET Propagation of Least Common multiple Routing and Fuzzy Logic

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Computers, materials & Continua 2022年第7期72卷 1831-1845页

作者： v.Gayatri m.Senthil Kumaran Department of Computer Science and Engineering SCSVMV UniversityEnathurKanchipuram631561India

mobile Ad Hoc Network(mANET)is a group of node that would interrelate among each other through onemulti-hop wireless link,wherein the nodes were able to move in response to sudden *** objective of mANET routing protocol is to quantify the route and compute the best path,but there exists a major decrease in energy efficiency,difficulty in hop selection,cost estimation,and efficient *** this paper,a novel least common multipath-based routing has been *** routing is used to find a multipath route from source and *** balancing is of primary importance in the mobile ad-hoc networks,due to limited bandwidth among the nodes and the initiator of the load routing discovery phase in the multipath routing *** logic for load balancing multipath routing in mANETs is proposed,which ensures the data packets are sent through a path with the variance of binary sets to predict the original transformation of the data to be received in the *** main objective of the proposed system is to reduce the routing time of data packets and avoid the traffic based on multipath source and *** experimental results have to verify 96.7%efficiency in balancing the load.

关键词： mANETs multipath routing least common multiple routing(LCmR)and fuzzy logic route requests(RREQs) route replies(RREPs)

magnetization dynamics of mixed Co–Au chains on Cu(110) substrate:Combined ab initio and kinetic monte Carlo study

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Chinese Physics B 2015年第9期24卷 474-478页

作者： K.m.Tsysar S.v.Kolesnikov A.m.Saletsky Faculty of Physics Lomonosov Moscow State University

We present an investigation of the one-dimensional ferromagnetism in Au–Co nanowires deposited on the Cu（110）surface. By using the density functional theory, the influence of the nonmagnetic copper substrate Cu（110） on the magnetic properties of the bimetallic Au–Co nanowires is studied. The results show the emergence of magnetic anisotropy in the supported Au–Co nanowires. The magnetic anisotropy energy has the same order of magnitude as the exchange interaction energy between Co atoms in the wire. Our electronic structure calculation reveals the emergence of new hybridized bands between Au and Co atoms and surface Cu atoms. The Curie temperature of the Au–Co wires is calculated by means of kinetic monte Carlo simulation. The strong size effect of the Curie temperature is demonstrated.

关键词： magnetic properties nanowires density functional theory kinetic monte Carlo simulation

A model for the chain-to-plane charge transfer in YBa2Cu3O6+x

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Chinese Physics B 2012年第11期21卷 450-454页

作者： v.m.matic N.Dj.Lazarov m.milic Laboratory of Theoretical Physics Institute of Nuclear Sciences “Vinca”Belgrade University

A model for the chain-to-plane charge transfer is proposed to account for the two plateaus,at 60 K and at 90 K,of the Tc(x) characteristics of the YBa2Cu3O6+x high-Tc *** is assumed that the number of holes transferred from a CuO chain of length l to two nearby CuO2 sheets is proportional to l(that is,to the number of oxygen atoms in the chain),if the chain length is greater than,or equal to,a certain critical chain length,lcr,that is required to trigger the charge transfer *** holes are assumed to have been transferred from chains of length l更多还原AbstractFilter('ChDivSummary', 'ChDivSummarymore', 'ChDivSummaryReset');

关键词： YBCO oxygen ordering critical temperature doping

Impact of viscosity on DNA Dynamics

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Chinese Physics Letters 2007年第5期24卷 1210-1213页

作者： S. ZDRAvKOvIC m. v. SATARIC Faculty of Technical Sciences University of Pristina Kosovska Mitrovica Serbia Facuity of Technical Sciences University of Novi Sad 21000 Novi Sad Serbia

We study the influence of viscosity on DNA dynamics. By employing the nonlinear Peyrard-Bishop-Dauxois （PBD） model, it is shown that the DNA dynamics can be explained by a solution of a complex nonlinear Schrǒdinger equation （CNLSE）. This is the nonlinear Schrǒdinger equation （NLSE） with a nonlinear parameter being a complex number. We compare real and imaginary parts of this nonlinear parameter and show that the latter one should not be negligible, which means that the CNLSE should be solved numerically,

关键词： BREATHER mODEL

Analysis of Rheological Behavior of Some Aqueous PEO Gels under Thermal Treatment

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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

Evolution of viscosity of some aqueous poly （ethylene oxide） gels is observed as functions of polymeric concentration and temperature for samples subjected to thermal shock. The experimental data are analyzed following an appropriate algorithm, and reveal the transient effect from Newtonian to non-Newtonian flow as a function of the polymeric concentration.

关键词： Soft matter liquids and polymers Fluid dynamics

Effect of Ta_(2)O_(5)nanoparticles on bioactivity,composition,structure,in vitro and in vivo behavior of PEO coatings on mg-alloy

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Journal of magnesium and Alloys 2024年第6期12卷 2360-2379页

作者： D.v.mashtalyar I.m.Imshinetskiy v.v.Kashepa K.v.Nadaraia m.A.Piatkova A.I.Pleshkova K.A.Fomenko A.Yu.Ustinov S.L.Sinebryukhov S.v.Gnedenkov Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok690022Russia Far Eastern Federal University Vladivostok690950Russia Regional Clinical Dermatovenerological Dispensary Vladivostok690033Russia

The present study investigates the physical and chemical characteristics,behavior in vitro and in vivo,and biocompatibility of coatings containing Ta_(2)O_(5),which are obtained by plasma electrolytic oxidation(PEO)on mA8 magnesium *** obtained coatings demonstrate in vivo biocompatibility and in vitro *** to the base PEO coating,the layers containing Ta_(2)O_(5)facilitate the development of apatite in simulated body fluid,suggesting that the inclusion of nanoparticles improves bioactivity of the *** was found that incorporation of Ta_(2)O_(5)nanoparticles increases roughness and porosity of the formed layers by increasing particle concentration in electrolytes for the PEO process contributing to sufficient soft tissue ingrowth in *** on in vivo studies,these coatings also provide favorable tissue response and minimal inflammatory reaction in comparison with the bare magnesium alloy due to protection of living tissues from deleterious corrosion events of magnesium implant such as local alkalization and intense hydrogen *** results obtained in the present study concluded biocompatibility,tissue integration of the PEO coatings containing Ta_(2)O_(5)nanoparticles making them a promising protective layer for biodegradable magnesium implants.

关键词： Plasma electrolytic oxidation Bioactive coatings Tantalum pentoxide Simulated body fluid(SBF) Apatite formation Histology

Radial variations in xylem sap flux in a temperate red pine plantation forest

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Ecological Processes 2021年第1期10卷 328-336页

作者： Alanna v.Bodo m.Altaf Arain School of Earth Environment and SocietyMcMaster UniversityHamiltonONCanada mcmaster Centre for Climate Change HamiltonONCanada

Background:Scaling sap flux measurements to whole-tree water use or stand-level transpiration is often done using measurements conducted at a single point in the sapwood of the tree and has the potential to cause significant *** studies have shown that much of this uncertainty is related to(i)measurement of sapwood area and(ii)variations in sap flow at different depths within the tree ***:This study measured sap flux density at three depth intervals in the sapwood of 88-year-old red pine(Pinus resinosa)trees to more accurately estimate water-use at the tree-and stand-level in a plantation forest near Lake Erie in Southern Ontario,*** showed that most of the water transport(65%)occurred in the outermost sapwood,while only 26%and 9%of water was transported in the middle and innermost depths of sapwood,***:These results suggest that failing to consider radial variations in sap flux density within trees can lead to an overestimation of transpiration by as much as 81%,which may cause large uncertainties in water budgets at the ecosystem and catchment *** study will help to improve our understanding of water use dynamics and reduce uncertainties in sap flow measurements in the temperate pine forest ecosystems in the Great Lakes region and help in protecting these forests in the face of climate change.

关键词： Sap flow Transpiration Water use Red pine Temperate forest Great Lakes region

Synthesis and forming behavior of aluminium-based hybrid powder metallurgic composites

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International Journal of minerals,metallurgy and materials 2014年第2期21卷 181-189页

作者： m.Ravichandran A.Naveen Sait v.Anandakrishnan Department of mechanical Engineering Chendhuran College of Engineering and Technology Department of Production Engineering National Institute of Technology

Aluminium-based metal matrix composites were synthesized from Al-TiO2-Gr powder mixtures using the powder metallurgy technique and their forming characteristics were studied during cold upsetting. Green cylindrical compacts of pure Al, Al-5wt%TiO2, Al-5wt%TiO2-2wt%Gr, and Al-5wt%TiO2-4wt%Gr were made using a 400-kN hydraulic press equipped with suitable punch and die and by sintering at （590 ± 10）°C for 3 h. Cold upset forging tests were carried out, the true axial stress （σz）, the true hoop stress （σ？）, and the true hy-drostatic stress （σm） were evaluated and, their behavior against the true axial strain （εz） was also analyzed. It is observed that the addition of 5wt%TiO2 into the Al matrix increasesσz,σ？, andσm. The addition of both TiO2 and Gr reinforcements reduces the densification and defor-mation characteristics of the sintered preforms during cold upsetting. microstructure analyses of the as-sintered and cold upset forged speci-mens also were carried out to substantiate the experimental results.

关键词： metal matrix composites cold upsetting powder metallurgy workability

Hot Deformation Characteristics of 34Crmo4 Steel

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Journal of Iron and Steel Research International 2010年第12期17卷 65-69页

作者： S v Sajadi Far m Ketabchi m R Nourani mining and metallurgical Engineering Department Amirkabir University of Technology

The 34Crmo4 （AISI 4130） steel is extensively utilized in the compressed natural gas cylinders. Due to the importance of thermomechanical processing in the production of these cylinders, the dynamic reerystallization （DRX） characteristics of 34Crmo4 steel were investigated. The effect of hot deformation parameters such as temperature and strain rate on the dynamic restoration processes of a 34Crmo4 alloy was studied. Hot compression tests were performed in the temperature range of 900 to 1 100 ℃ and the strain rate range of 0. 001 to 0.1 s-1. Hot workability of this alloy has been analyzed by employing flow localization parameter. The flow curves observed are typical of occurrence of dynamic recrystallization and have exhibited single or multiple peaks in flow stress curve before reaching steady state, depending on the temperature and strain rates. The flow stress decreases with the increase of deformation temperature and the decrease of strain rate. Finally the activation energy obtained in this research is 490. 749 kJ/mol.

关键词： 34Crmo4 steel hot deformation activation energy dynamic recrystalization