学科分类
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494 个结果
  • 简介:Ascanningnear-fieldopticalmicroscopeusinguncoatedfibertipisdescribed,whichcanworkintransmissionandreflectionconfigurations,bothcapableofworkinginilluminationandcollection-mode,sothateithertransparentoropaquesamplecanbeinvestigated.Dependingondifferentapplications,eitherconstant-gaporconstant-heightimagescanbeachieved.Acompacthomemadetranslatorpermitstoselectinterestedareaofsampleintherangeof4mm×4mm.Workingintheconstant-heightaswellastransmissionandcollection-modeconfiguration,severalkindsofsamplessuchasholographicgrating,liposomeandzeolitewereinvestigated.TheexperimentalresultsrevealedthedependenceoftheopticalresolutionoftheSNOMonthetip-sampleseparation.

  • 标签: 近场光学 扫描电镜 光学分辨率
  • 简介:StabilizedorChebyshevexplicitmethodshavebeenwidelyusedinthepasttosolvestiffordinarydifferentialequations.MakinguseofspecialpropertiesofChebyshev-likepolynomials,thesemethodshavefavorablestabilitypropertiescomparedtostandardexplicitmethodswhileremainingexplicit.Anewclassofsuchmethods,calledROCK,introducedin[Numer.Math.,90,1-18,2001]hasrecentlybeenextendedtostiffstochasticdifferentialequationsunderthenameS-ROCK[C.R.Acad.Sci.Paris,345(10),2007andCommun.Math.Sci,6(4),2008].InthispaperwediscusstheextensionoftheS-ROCKmethodstosystemswithdiscretenoiseandproposeanewclassofmethodsforsuchproblems,theT-ROCKmethods.Onemotivationforsuchmethodsisthesimulationofmulti-scaleorstiffchemicalkineticsystemsandsuchsystemsarethefocusofthispaper,butournewmethodscouldpotentiallybeinterestingforotherstiffsystemswithdiscretenoise.TwoversionsoftheT-ROCKmethodsarediscussedandtheirstabilitybehaviorisanalyzedonatestproblem.ComparedtotheT-leapingmethod,asignificantspeed-upcanbeachievedforsomestiffkineticsystems.Thebehavioroftheproposedmethodsaretestedonseveralnumericalexperiments.

  • 标签: 切比雪夫 离散噪声 刚性常微分方程 动力学系统 随机微分方程 ACAD
  • 简介:Thispaperdevelopesatemperaturecontrolsysteminordertocarryoutarealtimeandcontinuousobservationonlivingcellsunderthemicroscope.Inthissystem,transparentindiumtinoxid(ITO)conductivefilmwasusedasaheater,temperaturewasmeasuredbythetemperaturedependenceofresistancebehavioroftheITOfilm,C8051F340single-clupwasusedasthecontrolhardwarecore,andthemodifiedPIDalgorithmandpulsewidthmodulation(PWM)wereadoptedasthekeycontrolsoftwareprograms.Thetemperaturesystemhadasimplestructurewithoutaddedtemperaturesensor,anuniformtemperaturedistributionwithin±1℃ontheITOfilmsurfaceandtemperaturecontrolprecisionof±0.2℃couldbeobtained.ThesystemcouldmaintainagoodgrowthstateforBHK-21livingcellunderthemicroscopefor48h.

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  • 简介:ASchwarzschildmicroscopewithanumericalapertureof0.2andamagnificationof130ina100μmfieldofview(FOV)isdesignedandisworkingat13.5nm.Meanwhile,aCCDisusedasadetectorwithapixelsizeof13μm×13μmandimagingareaof13mm×13mm.Theimagingqualitywithtolerancesofsystemanderrorsofmirrorsareconsidered.Weobtainthatthebeston-axesobjectresolutioncanbeuptoabout200nm,theaveragevalueis230nm,andtheresolutionisabout360nmat80μmFOV.

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  • 简介:离子光子排放显微镜学(IPEM)是新导致离子的排放显微镜学。它与高精力和在一件样品上侵犯的低fluence率采用一根宽广离子横梁。一个单个离子的位置被一个光系统与联合的客观透镜,棱柱,显微镜试管和充电检测设备(电荷耦合器件)。与Ag离子做的一部薄ZnS电影被用作光材料。在照耀的Cl离子创造的ZnS(Ag)电影的光子的产生效率和传播效率是计算的。一个单个Cl离子光显微镜的图象被高量效率电荷耦合器件观察。在这个IPEM系统给的一个单个Cl离子的分辨率是6m。影响分辨率的几个因素被讨论。一根硅二极管被用来收集事件离子引起的电的信号。光图象和电子信号的有效、意外的巧合被说明。单个事件效果的一张二维的地图根据有效巧合的数据被抽出。

  • 标签: 单粒子效应 光子发射 离子束 显微镜 效应试验 ZNS薄膜
  • 简介:Atomicforcemicroscope(AFM)wasusedtoinvestigatethearrangementofcellulosemicrofibrils(CMF)inMosobamboo(Phyllostachyspubescens)fibers.Twomethodsofsamplepreparationwereusedherefordifferentpurposes.Thefirstmethodwaschemicalmacerationwithamixtureofhydrogenperoxideandglacialaceticacid,throughwhichtheobtainedfibersweresuitableforobservingtheorientationofCMFintheprimarywal1.Theothermethodwastopreparetangentialmicrotomedsectionswithathicknesso...

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  • 简介:Capillaryforcesaresignificantlydominantinadhesiveforcesmeasuredwithanatomicforcemicroscope(AFM)inambientair,whicharealwaysthoughttobedependentonwaterfilmthickness,relativehumidity,andthefreeenergyofwaterfilm.Westudythenatureofthepull-offforceonavarietyofsurfacesasafunctionoftipvelocity.Itisfoundthatthecapillaryforcesareofrelativelystrongdependenceontipvelocity.ThepresentexperimentisexpectedtoprovideabetterunderstandingoftheworkmechanismofAFMinambientair.

  • 标签: 原子力显微镜 附着力 速度效应 毛细管力 自由能
  • 简介:Inthispaper,standardandeconomicalcascadicmultigridmethodsareconsideredforsolvingthealgebraicsystemsresultingfromthemortarfiniteelementmethods.Bothcascadicmultigridmethodsdonotneedfullellipticregularity,sotheycanbeusedtotacklemoregeneralellipticproblems.Numericalexperimentsarereportedtosupportourtheory.

  • 标签: 有限元方法 迫击炮 多重 瀑布 经济 标准
  • 简介:付春敏老师向我们推荐了这篇罗德尼·马丁有关教师在培养学生写作结构中促进思维能力发展的文章。在文中我们可以看到,以英文为母语的西方,教师更加着力于对学生的构思结构"大局"观的思维培养。文中对培养学生写作结构思维能力的剖析,望能对老师们的教育教学有所启示。

  • 标签: 思维能力 STORY 罗德尼 文中 PICTURE ORGANIZED
  • 简介:BioscienceMethods(ISSN1925-1920)isanopenaccess,peerreviewedjournalpublishedonlinebyBioPublisher.Thejournalpublishesallthelatestandoutstandingresearcharticles,lettersandreviewsinallareasofbioscience,therangeoftopicsincluding(butarenotlimitedto)technologyreview,techniqueknow-how,labtool,statisticalsoftwareandknown

  • 标签: BIOSCIENCE BM LETTERS SUBMISSION outstanding charg
  • 简介:BioscienceMethods(ISSN1925-1920)isanopenaccess,peerreviewedjournalpublishedonlinebyBioPublisher.Thejournalpublishesallthelatestandoutstandingresearcharticles,lettersandreviewsinallareasofbioscience,therangeoftopicsincluding(butarenotlimitedto)technologyreview,techniqueknow-how,labtool,statisticalsoftwareandknown

  • 标签: BIOSCIENCE BM letters submission outstanding CHARGES
  • 简介:BioscienceMethods(ISSN1925-1920)isanopenaccess,peerreviewedjournalpublishedonlinebyBioPublisher.Thejournalpublishesallthelatestandoutstandingresearcharticles,lettersandreviewsinallareasofbioscience,therangeoftopicsincluding(butarenotlimitedto)technologyreview,techniqueknow-how,labtool,statisticalsoftwareandknowntechnologymodification.Casestudiesontechnologiesforgenediscoveryandfunction

  • 标签: BIOSCIENCE BM letters submission outstanding CHARGES
  • 简介:Basedonapproximatetheoreticalanalysesonatypiealsphericalcellcontainingasphericalmicrovoid,theinfluencesofmatrixmaterials’microscopicscaleonthemacroscopicconstitutivepotentialthe-oryofporousmaterialandmicrovoidgrowthhavebeeninvestigatedindetail.Byassumingthattheplasticde-formationbehaviorofmatrixmaterialsfollowsthestraingradient(SG)plastictheoryinvolvingthestretchandrotationgradients,theratio(λ=l/a)ofthematrixmaterials’intrinsiccharacteristicLengthltothemicro-voidradiusaisintrodncedintotheplasticconstitutivepotentialandthevoidgrrothlaw.Thepresentresultsindicatethat,whentheradiusaofmicrovoidsiscomparablewiththeintrinsiccharacteristiclengthlofthematrixmaterials,theinfluenceofmicroscopicsizeeffectonneithertheconstitutivepotentialnorthemicro-voidevolutionpredictedcanheignored.Andwhenthevoidradiusaismuchlagerthantheintrinsiccharac-teristiclengthlofthematrixmaterials,thepresentmodelcanretrogressautomaticallytotheimprovedGur-sonmodelthattakesintoaccountthestrainhardeningeffectofmatrixmaterials.

  • 标签: strain GRADIENT PLASTICITY scale effect CONSTITUTIVE
  • 简介:Remote-modemicrospherenanoscopecanobservethenano-structureswith23nmfeaturesize.Itdoesnotrequiresamplepreparationandfunctionsinbothambientairandliquidenvironments.ComparedwiththescientificcharacterizationtoolslistedinTableS1,thesimpleandportablenaturemakesthemicrospherenanoscopeafavorablesolutionforgeneralpurposeimaginginpracticalfields,likehospitals,foodindustry,semiconductorproductionlines,schoolsandenvironmentagencies.

  • 标签: optical MICROSCOPE FOOD INDUSTRY
  • 简介:CascadicmultigridtechniqueformortarWilsonfiniteelementmethodofhomogeneousboundaryvalueplanarlinearelasticityisdescribedandanalyzed.FirstthemortarWilsonfiniteelementmethodforplanarlinearelasticitywillbeanalyzed,andtheerrorestimateunderL2andH1normisoptimal.Thenacascadicmultigridmethodforthemortarfiniteelementdiscreteproblemisdescribed.Suitablegridtrans-feroperatorandsmootheraredevelopedwhichleadtoanoptimalcascadicmultigridmethod.Finally,thecomputationalresultsarepresented.

  • 标签: 平面线性弹性 研钵威尔逊有限元法 多栅技术 弹性力学
  • 简介:Inthepresentpaperweextendthemethodpresentedby0.AxelssonandP.VassilevskicalledAMLPversion(i)ofrecursivelyconstructingpreconditionerforthestiffnessmatrixinthediscretizationofselfadjointsecondorderellipticboundaryvalueproblems.Inourextendedmethodthesystemstobeeliminatedoneachlevelcontainingthemajorblockmatricesofthegivenmatrixcanbesolvedapproximately,whiletheymustbesolvedexactlyintheoriginalmethod.

  • 标签: PRECONDITIONING MULTILEVEL method SCHUR complement.