学科分类
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27 个结果
  • 简介:DNAcondensationisanimportantprocessinmanyfieldsincludinglifesciences,polymerphysics,andappliedtechnology.Inthenucleus,DNAiscondensedintochromosomes.Inpolymerphysics,DNAistreatedasasemi-flexiblemoleculeandapolyelectrolyte.Manyagents,includingmulti-valentcations,surfactants,andneutralpoorsolvents,cancauseDNAcondensation,alsoreferredtoascoil–globuletransition.Moreover,DNAcondensationhasbeenusedforextractionandgenedeliveryinappliedtechnology.ManyphysicaltheorieshavebeenpresentedtoelucidatethemechanismunderlyingDNAcondensation,includingthecounterioncorrelationtheory,theelectrostaticzippertheory,andthehydrationforcetheory.Recentlyseveralsingle-moleculestudieshavefocusedonDNAcondensation,sheddingnewlightonoldconcepts.Inthisdocument,themulti-fieldconceptsandtheoriesrelatedtoDNAcondensationareintroducedandclarifiedaswellastheadvancesandconsiderationsofsingle-moleculeDNAcondensationexperimentsareintroduced.

  • 标签: 脱氧核糖核酸 阳离子表面活性剂 场方法 高分子物理 缩合机理 DNA
  • 简介:Thehumancardiovascularsystemisaclosedloopandcomplexvascularnetworkwithmulti-scaledheterogeneoushemodynamicphenomena.Here,wegiveaselectivereviewofrecentprogressinmacro-hemodynamicmodeling,withafocusongeometricalmulti-scalemodelingofthevascularnetwork,micro-hemodynamicmodelingofmicrocirculation,aswellasbloodcellular,subcellular,endothelialbiomechanics,andtheirinteractionwitharterialvesselmechanics.Wedescribeindetailthemethodologyofhemodynamicmodelinganditspotentialapplicationsincardiovascularresearchandclinicalpractice.Inaddition,wepresentmajortopicsforfuturestudy:recentprogressofpatient-specifihemodynamicmodelinginclinicalapplications,micro-hemodynamicmodelingincapillariesandbloodcells,andtheimportanceandpotentialofthemulti-scalehemodynamicmodeling.

  • 标签: 血流动力学 心血管系统 多尺度建模 动力学模型 临床应用 多尺度模型
  • 简介:Atheoreticalinvestigationiscarriedouttostudytheexistence,formationandbasicpropertiesofionacoustic(IA)doublelayers(DLs)inamagnetizedbi-ionplasmaconsistingofwarm/coldionsandBoltzmanndistributedelectrons.Basedonthereductiveperturbationtechnique,anextendedKortewegde-Vries(KdV)equationisderived.Thepropagationoftwopossiblemodes(fastandslow),andtheirevolutionareinvestigated.Theeffectsofobhqueness,magnitudeofthemagneticfield,ionconcentration,polarityofions,andiontemperatureontheIADLprofileareanalyzed,andthentherangesofparametersforwhichtheIADLsexistareinvestigatedindetails.

  • 标签: ION ACOUSTIC WAVES bi-ion PLASMA DOUBLE-LAYERS
  • 简介:Inthispaper,wederivethebi-Hamiltonianstructureofamulti-componentCamassa–Holmsystem,whichassociateswiththemulti-componentAKNShierarchyandmulti-componentKNhierarchyviathetri-Hamiltoniandualitymethod.Furthermore,thespectralproblemsofthedualhierarchiesmaybeobtained.

  • 标签: bi-Hamiltonian STRUCTURE DUAL HIERARCHIES Camasssa
  • 简介:Nanoparticlescanprovideflameretardancetohostingpolymersandactasnanofireextinguishers.Hydroxyapatite(Ca5(OH)(PO4)3)(HA)isnothygroscopic,andisthermallystableupto800℃,with18.5wt%phosphorouscontent.ItisthishighphosphorouscontentthatcanprovideHAwithflameretardantproperties.Inthispaper,wereportonthecontinuoussynthesisofultrafineHAusingahydrothermalsynthesistechnique.TheHAsurfacepropertieswerechangedfromhydrophilictohydrophobicbypostsynthesissurfacemodification.TheratiooftheHAnanoparticlesandanintumescentagentknownasExolitAP750wasinvestigatedtoyieldaself-extinguishingmulti-componentepoxynanocompositeforextendedapplicationunderextremefireconditions.TheHA/AP750/epoxynanocompositewasabletoresistaflameat1700℃andself-extinguishaftertheflamehadbeenremoved.Thenanocompositeshowedanenhancedflammabilityperformanceinstandardconecalorimetrytestingandformedacompactandcohesiveprotectivecharlayerwitha50%decreaseinpeakheatreleasedcomparedwithvirginepoxy.OuraimwastoestablishtheuseofHAasaneffectivenanofillerwithphosphorous-basedflameretardantproperties.Thesurfaceofthisnanofireextinguisherwasmodifiedeffectivelywithdifferentsurfactantsforenhancedcompatibilitywithdifferentpolymericmatrices.

  • 标签: 水热合成技术 表面改性 阻燃剂 连续流动 纳米复合材料 羟基磷灰石
  • 简介:Flocculationtimeisconventionallybelievedtobeproportionaltotheflocculationefficiencyofacylindricalfluidizedbedflocculator.However,inasingle-stagevelocitygradientsituation,theflocculationefficiencydecreaseswhentheoptimalflocculationtimeisexceeded.Amulti-stagevelocitygradientwasestablishedinacylindricalfluidizedbedflocculator,basedonthehydraulicclassificationtheory.Thismulti-stagevelocitygradientfluidizedbedflocculator(MGF)createdamoresuitableenvironmentforflocgrowthandprotection,whichwasconfirmedbythesizedistributionofflocsalongthebedheight.Correspondingly,theabatementefficienciesforKaolinslurryanddyedwastewatertreatmentintheMGFwereenhancedby5-10%,andby7-20%,respectively,comparedwiththoseinthesingle-stagevelocitygradientfluidizedbedflocculators(SGFs).TheinitialbedheightdistributionratioalongthevelocitygradientswasanimportantfactorforMGFoptimization.

  • 标签: 絮凝时间 速度梯度 流化床 多级 优化 圆筒形
  • 简介:直角的多匹配的追求(OMMP)是直角的匹配追求(OMP)的自然扩展.We作为M1是一个整数的OMMP(M)与参数M表示OMMP。OMP和OMMP(M)之间的主要差别是OMMP(M)每重复选择M原子,当OMP仅仅把一个原子加到最佳的原子集合时。在这份报纸,我们学习直角的多匹配的追求的表演在下面裂开。特别地,我们看那测量矩阵A是否满足(25年代,1/10)有12能恢复的M0=的-RIP,OMMP(M0)在s重复以内的s稀少的信号。我们而且证明OMMP(M)能为M的一个大班在O(s/M)重复以内恢复s稀少的信号。[从作者抽象]

  • 标签: 正交 性能 等距 迭代方法 匹配追踪 OMP
  • 简介:Usingbi-spinorfieldswewritethepseudo-scalarandbi-spinorfieldsthatarecharacterizedbythefieldfunctionsofcoordinatesofseveralparticles,namelymulti-particlefields.Byapplyingthequantizationproceduretothesemulti-particlefields,hadroniccreationandannihilationoperatorshavebeenobtained.

  • 标签: MULTI-PARTICLE FIELD OPERATORS
  • 简介:我们在场与多重奇特测量光旋涡的拓扑的费用的一个简单方法。用一个圆柱的透镜,一根旋涡横梁能与多重分开的黑暗的洞腐烂进轻地分布,谁的数,就等于输入横梁的拓扑的费用。这个结论然后与多重奇特经由实验和旋涡横梁的繁殖的数字模拟被验证。这个方法也是可靠的与奇特的不同分布测量宽带旋涡横梁的拓扑的费用,它不诉诸多重横梁interferometric实验。

  • 标签: 柱面透镜 拓扑荷 旋涡 光学 测量 奇异
  • 简介:Weproposeatwin-arraycapacitance(TAC)sensorforthemeasurementofconcentration,velocity,andflowrateofgas-solidtwo-phaseflow.Usingthesensitivitynon-uniformityofaneighboringelectrode,theregionalconcentrationofthecross-sectionwasreconstructeddirectly.Additionally,thefiniteelementmethodwasusedtoanalyzethecapacitanceofthesensorscomposedofadifferentnumberofelectrodes.TACsensorswith4,6,and8electrodeswerefoundtobethebestforregionalconcentrationmeasurements.Basedonthis,the8-electrodetwin-planeelectricalcapacitancetomography(ECT)sensor,the4-electrodeTACsensor,andthe6-electrodeTACsensorwereusedtomeasuretheconcentration,velocity,andflowrateofgranulesingranularflow.TheflowratesmeasuredbyECTandTACwerecomparedwiththeflowrateobtainedbyagravitysensortoverifythemeasurementaccuracy.Experimentsonverticalandinclinedpipelineswithgranularflowwerecarriedout.Wefoundthattheflowrateaccuracyofthe4-electrodeTACisdistinctlybetterthanthatofthe6-electrodeTACintheverticalpipelinewhiletheflowrateaccuracyofthe4-electrodeTACandthe6-electrodeTACweresimilarfortheinclinedpipeline.

  • 标签: 电容传感器 多参数测量 阵列 多相流 电极传感器 流量精度
  • 简介:在现在的纸,在有弹性的媒介嵌入的多围的碳nanotubes(MWCNT)的动态稳定性包括热环境效果被调查。到这个目的,一个非局部的Timoshenko横梁模型被开发它捕获小规模效果。碳nanotubes的动态管理方程包括轴的压缩力量的效果基于Timoshenko横梁理论被提出。然后,参量的研究被进行与简单地支持的结束支持在MWCNT的动态稳定性特征上调查静态的负担因素,温度变化,非局部的参数,苗条比率和有弹性的媒介的春天常数的影响。

  • 标签: 下线 服务 迁移
  • 简介:在这份报纸,我们给multi-Cauchy-Jensenmappings的二描述。他们之一减少定义这些mappings到一个单个功能的方程的n方程的系统。我们也证明,用固定的点方法,这个方程的概括Hyers-Ulam稳定性。我们的结果概括一些已知的结果。

  • 标签: 方程组 稳定性 映射 函数方程 定点法 柯西
  • 简介:Multi-nucleontransferreactionplaysanimportantroleinthesynthesisofnewnuclides[1].Inthereactionsof20Ne+209Bi,someshort-livednucleiproducedbytransferring26nucleonswerediscovered.Theexperimentof20Ne+209Biwasperformedatgas-filledrecoilseparatorinLanzhou[2].A400g/cm2thick209Bitargetwasbombardedwith20NebeamdeliveredbyacceleratorHIRFL.

  • 标签: Multi-nucleon TRANSFER REACTIONS
  • 简介:‘Stent对stent’研究是被设计与以前同意的相比显示出新stent图案的优势的一种使随机化的试用。这些研究被规章的机构通常使用,例如美国食物药品管理局(食物及药品管理局),到表示同意到新stent图案。有这些临床的试用的问题是他们的高费用和困难。在这份报纸,为‘stent对stent’的一种数字选择复杂临床的研究被介绍。一个有限元素模型被开发在冠的stent放置以后在结果上调查stent设计的影响。二商业地可得到的stents(NIR和多连接stents)被建模,他们的行为以压力分发在推广期间被比较,光线的获得,外部直径变化并且节略。而且,狭窄率上的stent设计的效果被在动脉以内比较压力分发调查。在stented动脉的动脉的墙压力的分析显示多连接stent设计原因与slotted试管NIR设计相比与局部性的stenotic损害降低应力到一个动脉粥样硬化患者容器。有观察临床的狭窄的调查结果相互关联与多连接stent设计相比在NIR评估狭窄率,它更高报导了。

  • 标签: 支架设计 动脉狭窄 有限元法 NIR 应用 多杆
  • 简介:Temperatureanddensityasymmetrydiagnosisiscriticaltoadvanceinertialconfinementfusion(ICF)science.Amultimonochromaticx-rayimager,MMI,recordsthespectralsignaturefromanICFimplosioncorewithtimeresolution,2Dspatialresolutionandspectralresolution.Whilenarrow-bandimagesand2Dspace-resolvedspectrafromtheMMIdataconstrainthetemperatureandthedensityspatialstructureofthecore,theaccuracyoftheimagesandthespectrahighlydependsonthequalityoftheMMIdataandtheprocessingtools.Here,wesyntheticallyinvestigatethecriterionforreliableMMIdiagnosticsanditseffectsontheaccuracyofthereconstructedimages.Thepinholearraytiltdeterminestheobjectspatialsamplingefficiencyandtheminimumreconstructionwidth,w.Whenthespectralwidthassociatedwithwissignificantlynarrowerthanthespectrallinewidth,thelineimagesreconstructedfromtheMMIdatabecomereliable.TheMMIsetuphastobeoptimizedforeveryapplicationtomeetthiscriterionforreliableICFdiagnostics.

  • 标签: high power laser INERTIAL CONFINEMENT fusion
  • 简介:Forsyngasproduction,thecombustionoffossilfuelsproduceslargeamountsofCO2asagreenhousegasannuallywhichintensifiesglobalwarming.Inthisstudy,chemicalloopingcombustion(CLC)hasbeenutilizedfortheeliminationofCO2emissiontoatmosphereduringsimultaneoussyngasproductionwithdifferentH2/COratioinsteamreformingofmethane(SR)anddryreformingofmethane(DR)inaCLC-SR-DRconfiguration.InCLC-SR-DRwith184reformertubes(similartoanindustrialscalesteamreformerinZagrosPetrochemicalCompany,Assaluyeh,Iran),DRreactionoccursoverRh-basedcatalystsin31tubes.Also,SRreactionishappenedoverNi-basedcatalystsin153tubes.CLCviaemploymentofMn-basedoxygencarrierssuppliesheatforDRandSRreactionsandproducesCO2andH2Oasrawmaterialssimultaneously.AsteadystateheterogeneouscatalyticreactionmodelisappliedtoanalyzetheperformanceandapplicabilityoftheproposedCLC-SR-DRconfiguration.Simulationresultsshowthatcombustionefficiencyreached1attheoutletoffuelreactor(FR).Therefore,pureCO2andH2OcanberecycledtoDRandSRsides,respectively.Also,CH4conversionreached0.2803and0.7275attheoutletofSRandDRsides,respectively.Simulationresultsindicatethat,3223kmolh-1syngaswithaH2/COratioequalto9.826wasproducedinSRsideofCLC-SR-DR.Afterthat,1844kmolh-1syngaswithaH2/COratioequalto0.986wasachievedinDRsideofCLC-SR-DR.ResultsillustratethatbyincreasingthenumberofDRtubesto50tubesandconsidering184fixedtotaltubesinCLC-SR-DR,CH4conversionsinSRandDRsidesdecreased2.69%and3.31%,respectively.However,thissubjectcausedtotalsyngasproductioninSRandDRsides(inallof184tubes)enhanceto5427kmolh-1.Finally,thermalandmolarbehaviorsoftheproposedconfigurationdemonstratethatCLC-SR-DRisapplicableforsimultaneoussyngasproductionwithhighandlowH2/COratiosinanenvironmentalfriendlyprocess.

  • 标签: 甲烷重整 蒸汽重整 合成气 CO2 CLC 生产
  • 简介:Thisstudypresentsathree-dimensionalnumericalstudyofthemixingandsegregationofbinaryparticlemixturesinatwo-jetspoutfluidizedbedbasedonanEulerian-Eulerianthree-fluidmodel.Initially,theparticlemixtureswerepremixedandpackedinarectangularfluidizedbed.Asthecalculationbegan,thegasstreamwasinjectedintothebedfromthedistributorandjetnozzles.Themodelwasvalidatedbycomparingthesimulatedjetpenetrationdepthswithcorrespondingexperimentaldata.Themainfeaturesofthecomplexgas-solidflowbehaviorsandthemechanismofmixingandsegregationofthebinarymixtureswereanalyzed.Moreover,furthersimulationswerecarriedouttoevaluatetheeffectsofoperatingconditionsonthemixingandsegregationofbinaryparticlemixtures.Theresultsillustratethatmixingcanbeenhancedbyincreasingthejetvelocityorenlargingthedifferenceofinitialproportionsofbinaryparticlemixtures.

  • 标签: 二元颗粒混合物 三维数值模拟 喷动流化床 分离机理 多相 射流穿透深度