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13 个结果
  • 简介:Wecommunicatemanydifficultiesthatweencounterwhenattemptingtopinpointacommonoriginfortheseveralobservedanomalies[1;2]orassessingtheirtensionwithexistingexclusionlimits.Theseincludesystematicsaffectingtheoperationofthedetectors,ourknowledgeoftheirresponse,astrophysicaluncertainties,andthebroadrangeofparticlecouplingsthatcanmediatetheinteractionwithadetectortarget.Theinterestingastrophysicalevidence[2]thatmotivatesasearchfordark-photonandfocusesourattentiononaHiddenValleysmodelwithaGeV-scaledarksectorthatproducesexcitingsignatures.Resultsfromtherecentundergroundexperiments[1]arealsoconsidered.

  • 标签: RECENT PROGRESS SIGNATURES
  • 简介:1.ThemutationbreedingofplantsIn2016,themutationmechanismofvariousplantmutantsincludingArabidopsisthaliana,Geranium,Trades-cantiauminensis,TaraxacumkoksaghyzRodinandalgaeobtainedbyheavyionbeammutationbreedingtechniqueswereinvestigated.Thegenome-wideprofilingofanArabidopsismutantnamedcivar(CarbonionbeamsInducedVariegated)wasrevealedbyusingre-sequencingandtheroughmap-basedcloningtechniques.AphenotypescreeningofArabidopsisthalianairradiatedbycarbonionbeamsbasedonhigh-throughputimagingtechniquecombiningtheprincipalcomponentanalysisandscattermatrixclusteringanalysiswasbuiltandoptimizedwhichcanscreenthevariationofplantmutantpopulations.Thepigmentcomponentsandquantitiesandexpressionprofilesofkeygenesinvolvedinanthocyaninbiosynthesisofflower-colormutantofGeraniumandleaf-colormutantofTrades-cantiauminensiswereinvestigated.MutationbreedingofTaraxacumkoksaghyzRodininducedbycarbonionbeamirradiationswhichisnotableforitsproductionofhighqualityrubberandinulinwasstarted.Inaddition,thephotosyntheticresponseofthemutantsofScenedesmusquadricaudawithalteredpigmentfeatureswereanalyzed.

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  • 简介:Arabidopsisthalianaisacommonresearchplantofmolecularandcellbiologicalresearchwhichhasshortlifecycleandhugeamountofseeds[1].Gammarayisoneoftheimportantphysicalmutagenswhichiswidelyusedinplantgeneticsandbreedingresearch[2].Thepurposeofthisstudyistoinvestigatethedose-effectofrayradiationsontherootdevelopmentofArabidopsis.Dryseedswereirradiatedbyrayswiththedoserangefrom100to1600Gy.

  • 标签: EFFECT IRRADIATION GROWTH
  • 简介:SmallRNA(sRNA)-mediatedpost-transcriptionalregulationdiffersfromprotein-mediatedregulation.Throughbasepairing,sRNAcanregulatethetargetmRNAinacatalyticorstoichiometricmanner.Sometheoreticalmodelswerebuiltforcomparisonoftheprotein-mediatedandsRNA-mediatedmodesinthesteady-statebehaviorsandnoiseproperties.ManyexperimentsdemonstratedthatasinglesRNAcanregulateseveralmRNAs,whichcausescrosstalkbetweenthetargets.Here,wefocusonsomemodelsinwhichtwotargetmRNAsaresilencedbythesamesRNAtodiscusstheircrosstalkfeatures.Additionally,thesequence-functionrelationshipofsRNAanditsroleinthekineticprocessofbase-pairinghavebeenhighlightedinmodelbuilding.

  • 标签: 调控理论 RNA介导 细菌 小RNA 碱基配对 转录后调控
  • 简介:ThecokedepositiononHZSM-5/SAPO-34compositecatalystshasbeenstudiedintheconversionofethanoltopropylene.TheHZSM-5/SAPO-34compositecatalystsweresynthesizedbyhydrothermalmethod(ZS-HS)andfullyblending(ZS-MM).TheusedcatalystswerecharacterizedbyXRD,N2adsorption–desorption,TGA,TPO,elementalanalysis,FTIRandXPS.ThecokingkineticsonbothZS-HSandZS-MMhasbeeninvestigatedandtheircokingrateequationswereobtained.TheusedZS-MMcatalysthadhigheramountofcokeandlowernC:nHthantheusedZS-HS.90%ofthecokewasdepositedinthemicroporesofZS-HS,whilealmost45%ofthecokelocatedinthemicroporesofZS-MM.ThecokedepositedonZS-HScatalystwasmainlygraphite-likecarbonspecies,whereasdehydrogenatedcokespecieswasthemajoronZS-MM.ThecokingactivationenergyofZS-MMwaslowerthanthatofZS-HS,andthecokingrateonZS-MMwasfasterthanonZS-HS.Inaddition,theregenerationofZS-MMcatalystshowedthatithadagoodhydrothermalstability.Thedifferencesoncokingbehaviorsonthetwocatalystswereduetotheirdifferentacidicpropertiesandtextures.

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  • 简介:本文基于迈克尔逊干涉光路,采用硅光电池作为传感器,检测橡胶板的内部气泡尺寸.该方法在橡胶板上粘贴反射铝膜,采用抽真空或加热的方法,使橡胶板内部气泡发生膨胀,从而使干涉条纹随着表面形变发生移动.基于硅光电池对于光强变化的快速响应,示波器可采集干涉条纹的移动电压脉冲信号,从而计算出橡胶板表面微小形变尺寸.

  • 标签: 实验教学 光电传感实验 顶点课程
  • 简介:Inthisstudy,weevaluatethevaluesoflatticethermalconductivityκLoftypeIIGeclathrate(Ge34)anddiamondphaseGecrystal(d-Ge)withtheequilibriummoleculardynamics(EMD)methodandtheSlack'sequation.ThekeyparametersoftheSlack'sequationarederivedfromthethermodynamicpropertiesobtainedfromthelatticedynamics(LD)calculations.TheempiricalTersoff'spotentialisusedinbothEMDandLDsimulations.Thethermalconductivitiesofd-Gecalculatedbybothmethodsareinaccordancewiththeexperimentalvalues.ThepredictionsoftheSlack'sequationareconsistentwiththeEMDresultsabove250KforbothGe34andd-Ge.Inatemperaturerangeof200-1000K,theκLvalueofd-GeisaboutseveraltimeslargerthanthatofGe34.

  • 标签: 特性方程 分子 时差 热传输 晶格热导率 电解二氧化锰
  • 简介:Recently,RNAprocessinghasemergedasanovelpathwaythatmaycontributetothemaintenanceofgenomestability[1].Alternativesplicingisakeymolecularmechanismforincreasingthefunctionaldiversityoftheeukaryoticproteomes,butitalsooftenalteredincancer.Mountingevidenceindicatesthatalternativesplicing,theprocessthatallowsproductionofmultiplemRNAvariantsfromeachgene,contributestotheheterogeneityofthedisease[2].Althoughthemechanismofalternativesplicingvariantincancerisunclear,thecancer-specificalternativesplicingvariantshavebeenobservedinavarietyofhumancancersandcancercelllinesandhavebeenconnectedtotumorgenesis.

  • 标签: CARBON ION IRRADIATION
  • 简介:悬臂梁微小形变的电测法是大学物理实验课程中重要的综合应用型实验之一。由于课程内容的需要,一般忽略砝码加载后的悬臂梁变形,因此必须在应变可测的前提下,悬臂梁的变形角足够小。文章通过对悬臂梁设计厚度和长度的优化计算,使得在较小的悬臂梁变形角和较小的砝码重量条件下,应变可以被常用单臂电桥较为精确的测量,实现了该实验的测量准确度和仪器装置可操作性的最佳平衡。

  • 标签: 悬臂梁 应变片 变形角
  • 简介:设计了一套利用圆盘放大和普通长度测量工具相结合的测量微小长度的工具,分别利用该设计装置和螺旋测微器对钢丝的直径和普通A4纸张的厚度进行了测量。结果显示了新设计的可行性、创新性和数据的高精度性、准确性。

  • 标签: 微小长度测量 圆盘 实验 游标卡尺 螺旋测微器
  • 简介:随着科技的发展,对测量微小物体尺寸的精确度、速度都提出了新的要求,作者曾提出过一种基于激光发射测量微小物体尺寸的技术(见文献1)。该技术原理简单,测量微小物体尺寸的误差可控。然而,该技术在测量物体的大小方面还存在着一定的局限性;同时为了使系统达到最大测量范围,小齿的斜面与底板夹角a在实际过程中需要讨论。本研究对实验装置进行适当改进,从而解决了上述瓶颈问题。

  • 标签: 激光反射 微小距离测定