简介:ThereflectionandtransmissionofLambwavesatoverlapjointsareresearchedbythenumericalmethodandtheexperiments.ThenumericalmethodisusedtosimulatethereflectionandtransmissionofLambwavesatweldswithdifferentwidthson2mm-thickstainlesssteelplates.Thereflectionandtransmissioncoefficientsarecalculatedaswell.Whentheweldswidthislessthan4mm,aquasi-linearcorrelationisobservedbetweenthereflectioncoefficientofSOmodeandtheweldwidth.Incontrasttotheweldwidth,boththegapbetweentwoplatesandthereinforcementheightofwelddonothaveobviouseffectonthereflectioncoefficient.Basedontheresults,weproposethattheweldwidthcouldberapidlymeasuredthroughexaminingtheechoamplitudeofSOmode.Experimentsfurtherconfirmthequasilinearcorrelationandthefeasibilityofourproposedmethod.
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简介:StructurehealthmonitoringbasedondiagnosticLambwaveshasbeenfoundtobeoneofthemostpromisingtechniquesrecently.Thispaperhasabriefreviewofthenewdevelopmentsonthismethodincludingthebasicnovelofthemethod,fundamentalsandmathematicsofLambwavepropagation,narrowbandandwidebandLambwaveexcitationmethods,optimizationofexcitationfactorsanddiagnosticLambwaveinterpretationmethods.
简介:AllfactorsaffectingthePCRsysteminPinusmassonianaLambwereinvestigatedonebyone.TheresultsshowthattheoptimumPCRsystemofEST-SSRwere:2μL10×Buffer(Mg2+Free),30ngtemplateDNA,0.1875mmol/LdNTPs,3.75mmol/LMg2+,8pmolprimerpair,1.0UTaqDNApoly-meraseintotal20μLreactionsystem.Finally,atotalof11isolatesofP.massonianawasusedfortestingthestabilityofthePCRamplification.TheresultsprovethattheoptimumPCRsystemwasstable,reliable,highlyrepetitive.
简介:ThesolutionsofGreen'sfunctionaresignificantforsimplificationofproblemonatwo-phasesaturatedmedium.UsingtransformationofaxisymmetriccylindricalcoordinateandSommerfeld'sintegral,superpositionoftheinfluencefieldonafreesurface,authorsobtainedthesolutionsofatwo-phasesaturatedmediumsubjectedtoaconcentratedforceonthesemi-space.
简介:AprotocolformicropropagationusingnodalexplantsfrommaturePinusmassonianatreeshasbeendeveloped.Timeofexplantcollectioniscrucialfortheinitialsuccessofasepticculture.ExplantscollectedinearlyMarchgavethehighestpercentageofexplantsurvival(64.5%)andshoot-formingpercentage(52.3%).Thidiazuron(TDZ)concentrationsignificantlyinfluencedshootformation;4lMTDZwasoptimum,with4.8shootsproducedperexplantwithameanlengthof7.1cmafter120daysofculture.Regeneratedshootsrootedfor60daysinbasicmediumwith1lMNAAwerereadyforgrowthinpots.ThisisthefirstreportonplantletregenerationinvitrofrommaturetreesofP.massonianathatprovidesareliablemethodforpropagatingselectedelites.
简介:摘要目的对1例Lamb-Shaffer综合征患者进行基因变异分析,明确其可能的遗传学病因。方法对患者进行全外显子组测序(whole exome sequencing,WES),应用Sanger测序进行验证。结果WES结果显示患者SOX5基因存在c.1495delA(p.Thr499Glnfs*5)杂合变异,父母均未携带此变异,为新发变异,根据美国医学遗传学与基因组学学会遗传变异分类标准与指南,该变异判定为致病性变异(PVS1+PS2+PM2)。结论SOX5基因c.1495delA(p.Thr499Glnfs*5)变异可能是该Lamb-Shaffer综合征患者的遗传学病因。
简介:为实现飞机碳纤维复合材料(CarbonFiberReinforcedPlastics,CFRP)层板在役检测,采用同侧空气耦合超声兰姆波特征成像检测的方法对其缺陷进行检测。将非接触空气耦合超声传感器置于CFRP层板同侧,激发A0模态兰姆波,对其冲击损伤进行D扫描检测。引入时间反转损伤指数表征复合材料层板的冲击损伤。结合概率损伤算法,以该指数作为损伤重构成像的特征值,将不同扫描路径上的特征值数据进行融合,得到CFRP层板冲击损伤缺陷的兰姆波图像。结果表明,基于时间反转的兰姆波图像不仅能够直观地呈现损伤缺陷的位置和形状,而且能够通过避免基准信号选取和减少扫描步进次数显著提高检测效率。