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A COMPUTATIONAl APPROACH FOR OPTIMAl CONTROl SYSTEMS GOVERNED BY PARABOlIC VARIATIONAl INEQUAlITIES

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Journal of Computational Mathematics 2003年第6期21卷 815-824页

作者： N.H.Sweilam l.F.Abd-Elal Department of Mathematics Faculty of Science Cairo University Giza-EgyptDepartment of Mathematics Faculty of Science Cairo University Giza-Egypt

Iterative techniques for solving optimal control systems governed by parabolic varia-tional inequalities are presented. The techniques we use are based on linear finite elements method to approximate the state equations and nonlinear conjugate gradient methods to solve the discrete optimal control problem. Convergence results and numerical experiments are presented.

关键词： Parabolic variational inequalities finite elements method nonlinear conjugate gradient methods.

Hydrogen-induced dynamic slowdown of metallic glass-forming liquids

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Chinese Physics B 2021年第6期30卷 430-435页

作者： Jin-Ai Gao Hai-Shen Huang Yong-Jun lü School of Physics Beijing Institute of TechnologyBeijing 100081China

Dynamics of hydrogen doped Cu_(50) Zr_(50) glass-forming liquids are investigated by using the newly developed modified embedded atomic method(MEAM) potential based on molecular dynamics simulations. We find that the doping of hydrogen atoms slows down the relaxation dynamics, reduces the fragility of supercooled melts, and promotes the occurrence of glass transitions. The dynamic slowdown is suggested to be closely related to the effect of hydrogen atoms on locally ordered structure of melts. With increasing concentration of hydrogen, the five-fold symmetry associated with Cu-and Zr-centered polyhedrons is lowered, on the other hand, the local order featuring metal hydrides is enhanced. The latter dominates the dynamic behaviors of glass-forming liquids, especially for Zr atoms, and results in the dynamic slowdown.

关键词： metallic glasses hydrogen dynamics

RESEARCH ON lASER DIRECT DEPOSITION PROCESS OF Ti-6Al-4V AllOY

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Acta Metallurgica Sinica(English letters) 2007年第3期20卷 171-180页

作者： S.Y. Gao Y.Z. Zhang l.K. Shi B.l. Du M.Z. Xi H.Z. Ji Mechanical Engineering College Yanshan University O~mhuangdao 066004 China Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

laser direct deposition （lDD） of metallic components is an advanced technology of combining CAD/CAM （computer aided design/computer aided manufacturing）, high power laser, and rapid prototyping. This technology uses laser beam to melt the powders fed coaxiaUy into the molten pool by the laser beam to fabricate fuUy dense metallic components. The present article mainly studies the lDD of Ti-6Al-4V alloy, which can be used to fabricate aircraft components. The mechanical properties of the Ti-6Al-4V alloy, fabricated by lDD, are obtained using the tension test, and the oxygen content of used powders and deposited specimens are measured. In the present article, it can be seen that the mechanical properties obtained using this method are higher than the ones obtained by casting, and equal to those got by wrought anneal. One aircraft part has been made using the lDD process. Because of this aircraft part, with sophisticated shape, the effect of the laser scanning track on the internal soundness of the deposited part was discussed.

关键词： laser direct deposition Ti-6Al-4V alloy mechanical property depositing process aircraft component

Physicochemical properties and volatile components of pea flour fermented by lactobacillus rhamnosus l08

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Food Bioscience 2022年第2期46卷 793-800页

作者： Mengqi Pei Zifu Zhao Song Chen E.I.Reshetnik S.l.Gribanova Chun li Guofang Zhang libo liu lin Zhao Key laboratory of Dairy Sciences Ministry of EducationCollege of Food SciencesNortheast Agricultural UniversityHarbin150030China Inner Mongolia Yili Group Co.ltd Hohhot010080China Far Eastern State Agrarian University Blagoveshchensk675005Russia Heilongjiang Green Food Research Institute Harbin150028China Quality&Safety Institute of Agricultural Products Heilongjiang Academy of Agricultural SciencesHarbin150086China

Pea(Pisum sativum l.)is an important source of plant ***,the use of pea flour as a food ingredient is greatly limited due to its strong beany *** this work,we investigated the effects of lactobacillus rhamnosus l08(*** l08)fermentation on the physicochemical characteristics,amino acids composition and volatile flavor compounds of pea *** found that *** l08 had the probiotic potential of utilizing pea flour as fermentation *** l08 fermentation significantly increased the content of most amino acids,and total amino acid content increased from 222.18 mg/g at 0 h to 262.35 mg/g at 6 h.A total of 44 volatile compounds were identified in pea *** l08 fermentation increased the variety of acids and esters,while reduced the unpleasant flavor such as nonanal,decanal,octanal,1-hexanol and *** emulsifying stability and foam stability of pea flour were slightly enhanced during *** results illustrate that lactic acid bacteria fermentation is a promising approach to eliminate undesirable aroma of pea ***,this study provides theoretical support for the application of peas as high-quality protein source.

关键词： Pea flour lactic acid bacteria Fermentation Flavor component Physicochemical properties

Drosophila neuronal injury model allows for temporal dissection of neurodegenerative events

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Neural Regeneration Research 2016年第3期11卷 416-417页

作者： Barron l.lincolnⅡ lani C.Keller Department of Biological Sciences Quinnipiac University

Neurodegenerative diseases are extremely prevalent in today’s society and,according to the World Health Organization,are currently listed as the third leading cause of death,following cancer and heart disease（Gammon,2014）.The seminal characteristic of neuro-muscular degeneration is the complete disruption of the circuit between the brain,peripheral neuron,and muscle,

关键词： neuronal degeneration muscular dissection extremely Drosophila disruption currently listed today

Nesting innovations allow population growth in an invasive population of rose-ringed parakeets

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Current Zoology 2022年第6期68卷 617-626页

作者： Dailos HERNANDEZ-BRITO Jose l.TEllA Guillermo BlANCO Martina CARRETE Department of Conservation Biology Donana Biological Station(CSIC)Calle Americo Vespucio26Sevilla 41092Spain Department of Evolutionary Ecology Museo Nacional de Ciencias Naturales(CSIC)Calle JoseGutierrez Abascal2Madrid 28006Spain Department of Physical Chemical and Natural SystemsUniversidad Pablo de OlavideCarretera de Utrerakm 1Sevilla 41013Spain

Certain traits of recipient environments,such as the availability of limiting resources,strongly determine the establishment success and spread of non-native *** limitations may be overcome through behavioral plasticity,allowing them to exploit alternative ***,we show how a secondary cavity nester bird,the rose-ringed parakeet Psittacula krameri,innovates its nesting behavior as a response to the shortage of tree cavities for nesting in its invasive range in Tenerife(Canary Islands).We observed that some breeding pairs excavated their own nest cavities in palms,thus becoming primary cavity nester,whereas others occupied nests built with wood sticks by another invasive species,the monk parakeet Myiopsitta *** use of these novel nesting strategies increased the number of breeding pairs by up to 52%over 6 years,contributing to a 128.8%increase of the whole *** nests were located at greater heights above ground and were more aggregated around conspecifics but did not result in greater breeding success than natural *** of monk parakeet colonies by rose-ringed parakeets also benefited the former species through a protective-nesting association against nest *** results show how an invasive species innovate nesting behaviors and increase nest-site availability in the recipient environment,thus facilitating its population growth and invasion *** behavioral innovations in other invasive rose-ringed parakeet populations may be overlooked,and should be considered for effective management plans.

关键词： antipredator response behavioral flexibility biological invasions cavity nesters nesting innovation reproductive success

Effects of Carbon Content and Solidification Rate on the Thermal Conductivity of Grey Cast Iron

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Tsinghua Science and Technology 2008年第2期13卷 170-176页

作者： Daniel Holmgren Attila Diószegi Ingvar l. Svensson Department of Mechanical Engineering and Component Technology Jnkping University

The thermal conductivity/diffusivity of pearlitic grey irons with various carbon contents was investigated by the laser flash method. The materials were cast in controlled thermal environments producing three dissimilar cooling rates. The cooling rates together with the carbon content largely influence the thermal conductivity of grey iron. linear relationships exist between the thermal conductivity and the carbon content, the carbon equivalent, and the fraction of the former primary solidified austenite transformed into pearlite. The results show that the optimal thermal transport properties are obtained at medium cooling rates. Equations are given for the thermal conductivity of pearlite, solidified as pre-eutectic austenite, and the eutectic of grey iron. The thermal conductivity of pearlitic grey iron is modelled at both room temperature and elevated temperatures with good accuracy.

关键词： grey iron thermal conductivity thermal diffusivity carbon content carbon equivalent color etching graphite morphology eutectic cell size

The lipase monolayer film self-assembly on the negatively charged poly(ethylene terephthalate) substrate

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Chinese Chemical letters 2000年第3期11卷 267-270页

作者： lin, XF He, l Xu, lH lu, DS Chen, ZC Zhejiang Univ Ctr Anal & Measurement Hangzhou 310027 Peoples R China

The PET-CO2- film was prepared and the lipase was assembled on the surface of the PET-CO2- substrate The structure at the surface and activity of lipase/PET monolayer were studied by ATR-FTIR and AFM, and other methods.

关键词： self-assembled monolayer lipase PET-CO2 substrate

The locally Conservative Galerkin (lCG) Method — a Discontinuous Methodology Applied to a Continuous Framework

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Advances in Applied Mathematics and Mechanics 2009年第3期1卷 319-340页

作者： Rhodri l.T.Bevan Raoul vanloon Perumal Nithiarasu Civil and Computational Engineering Centre School of EngineeringSwansea UniversitySwansea SA28PPUK

This paper presents a comprehensive overview of the element-wise locally conservative Galerkin(lCG)*** lCG method was developed to find a method that had the advantages of the discontinuous Galerkin methods,without the large computational and memory *** initial application of the method is discussed,to the simple scalar transient convection-diffusion equation,along with its extension to the Navier-Stokes equations utilising the Characteristic Based Split(CBS)*** element-by-element solution approach removes the standard finite element assembly necessity,with an face flux providing continuity between these elemental *** face flux provides explicit local conservation and can be determined via a simple small post-processing *** lCG method obtains a unique solution from the elemental contributions through the use of simple *** is shown within this paper that the lCG method provides equivalent solutions to the continuous(global)Galerkin method for both steady state and transient *** numerical examples are provided to demonstrate the abilities of the lCG method.

关键词： Explicit local flux conservation element-by-element solution local conservation lCG convection-diffusion CBS artificial compressibility incompressible flow