简介:NASArotor37wasusedasablindtestcaseforturbomachineryCFDbytheTurbomachineryCommitteeoftheIGTI.Therotorisatransoniccompressorwithatipspeedof454m/s(1500ft/s)andarelativelyhighpressureratioof2.1.Itwastestedinisolationwithacircumferentiallyuniforminletflowsothattheflowthroughitshouldbesteadyapartfromandeffectsofpassagetopassagegeometryvariationandmechanicalvibration.Assuchitrepresentsthesimplestpossibletypeoftestforthree-dimensionalturbomachineryflowsolvers.Howerver,therotorstillpresentsarealchallengeto3Dviscousflowsolversbecausetheshockwave-boudarylayerinteractionisstrongandtheeffectsofviscosityaredominantindeterminingtheflowdeviationandhencethepressureration.Elevenblindsolutionsweresubmittewdandinadditionanon-blindsolutionwasusedtopreparefortheexercies.ThispaperreviewstheflowinthetestcaseandthecomparisonsoftheCFDsolutionswiththetestdata.LessonsforboththeFlowphysicsintransonicfansandfortheapplicationofCFDtosuchmachinesarepointedout.
简介:Wehavefoundthattheexcitedenergyfromthegroundstatewith1f7=2configurationtothefirstexcitedstatewith2p3=2configurationin37SisobviouslylowercomparedwiththatinnearbyN=21isotones35Si,39Arand41Ca(seeFig.1,Theinsertindicatestherelevantsingle-particleorbitsofprotonandneutron).ThisinterestingphenomenonmayresultfromthecollapseofN=28closure,whichgivesthesufficientvalencespaceforcollectivedeformationwhichcanbeenrevealedfromtheB(E2)value.Therefore,toobtaintheB(E2),weperformtheexperimentsformeasuringthelifetimeofthefirstexcitedstatein37S.
简介:Heavyionirradiationattractalargeinterestfortwoapplications:radiotherapyandspaceradiationprotectioninmannedspacemissions.ExposuretoheavyionsradiationresultsinmultipleeffectsthroughDNAdamageinduction.Single-cellgelelectrophoresisorcometassayisknownforitsabilitytodetectDNAdamageatthesinglecelllevelandhasbeenusedforyearstoassessDNAdamage.ItcandetectlowlevelsofDNAstrandbreaksinashorttime,justusingafewsamplecells.DNAdoublestrandbreaks(DSBs)aremeasuredattheneutralcometassaycondition;underthealkalinecometassayconditionbothDNAsinglestrandbreaks(SSBs)andpartDSBsaredetected.Thetwodimensionalcometassayisamodificationofthetwooriginalcometassay,cansimultaneouslydetectDNASSBsandDSBsinthesamehumanspermatozoa.
简介:Flowercolorastheimportanteconomicindicatorforornamentalplantshasbecometheprimarytargetforornamentalimprovingandbreeding.Heavyionmutationtechnologyasauniqueandefficientmutagenhasbeenwidelyusedingermplasminnovationandplantbreeding.Inourstudy,150youngshootsofPelargoniumwereexposedto80MeV/ucarbonionsandfinallyonestablegeneticflowercolormutantwasobtainedatdosageof30Gy.Comparingwithwildtype,thephysiologicalindexesofmutantdisplayedsignificantdifferences.Thecolorofpetalinmutantwaschangedfromredtolightpink,andthecolorofpeduncleandtoruswaschangedfromgreentored,aswellasthepistilsandstamens’colorwerechangedfromyellowgreentopurplishred.
简介:根据光的衍射理论,研究了靶面激光参数与传输距离的关系,得出了激光远距离上行传输情况下,靶面平均功率密度的外推计算方法,给出了具体的计算步骤,并对该方法进行了不确定度分析.结合具体的实验条件和实验测量结果,利用该方法计算了激光远距离传输情况下靶面平均功率密度.最后,根据特定的大气湍流结构模型,分析了大气传输修正系数与传输距离及发射仰角的关系.结果表明,大气传输修正系数与激光传输距离无关,与激光的发射仰角有关.但当测量路径上的大气相干长度大于8cm,且外推路径的发射仰角大于35°时,大气传输修正系数接近于1,此时,远距离传输情况下的激光参数可以采用几何外推方法计算.
简介:HighlytexturedHeusleralloyMn46Ni42Sn11Sb1ribbonswerepreparedbymeltspinning.TheannealedhighMncontentMn46Ni42Sn11Sb1ribboncross-sectionmicrostructure,crystalstructure,martensitictransformation(MT),andmagnetoresistance(MR)propertieswereinvestigated.TheMRintheannealedribbonwasassessedbythemagneticfielddirectionperpendiculartotheribbonsurfacewiththemagneticfieldupto30kOe.Thelargenegativevalueof25%forMRwasobtainedat244K.Theexchangebias(EB)effectsoftheas-spunandannealedribbonswereinvestigated.Afterannealing,theEBeffectshavebeenimprovedbyabout25Oeatthetemperatureof50K.Themagnetizationshaveincreasedapproximatelyby10%morethantheas-spunribbon.