简介:Intrinsiccarrierconcentration(ni)isoneofthemostimportantphysicalparametersforunderstandingthephysicsofstrainedSiandSi1-xGexmaterialsaswellasforevaluatingtheelectricalpropertiesofSi-basedstraineddevices.Uptonow,thereportonquantitativeresultsofintrinsiccarrierconcentrationinstrainedSiandSi1-xGexmaterialshasbeenstilllacking.Inthispaper,byanalyzingthebandstructureofstrainedSiandSi1-xGexmaterials,boththeeffectivedensitiesofthestatenearthetopofvalencebandandthebottomofconductionband(NcandNv)at218,330and393KandtheintrinsiccarrierconcentrationrelatedtoGefraction(x)at300KweresystematicallystudiedwithintheframeworkofKPtheoryandsemiconductorphysics.ItisfoundthattheintrinsiccarrierconcentrationinstrainedSi(001)andSi1-xGex(001)and(101)materialsat300KincreasessignificantlywithincreasingGefraction(x),whichprovidesvaluablereferencestounderstandtheSibasedstraineddevicephysicsanddesign.
简介:Veryrecently,theBelleandBESIIIexperimentsobservedanewcharmonium-likestateX(3823),whichisagoodcandidatefortheD-wavecharmonium(13D2).BecausetheX(3823)isjustneartheDˉDthreshold,thedecayX(3823)!J=+??canbeagoldenchanneltotestthesignificanceofcoupled-channeleffects.Inthiswork[1],thisdecayisconsideredincludingboththehidden-charmdipionandtheusualquantumchromodynamicsmultipoleexpansion(QCDME)contributions.
简介:摘要目的观察和评价通过肺结核X线影像特征与不典型肺结核常见误诊原因的探讨,以加强和提高对不典型肺结核的认识和诊断水平。方法选取我院2012年6月到2014年6月确诊的36例成人不典型肺结核,所有患者均以X线片证实。结果不典型肺结核主要指X线形态及部位的不典型,另外放射人员对不典型肺结核病的认识不足往往是导致临床误诊的重要因素。在36例患者中误诊为肺炎12例,占33.33%,慢性阻塞性肺病6例,占16.67%,支气管扩张1例,占2.78%,支气管炎2例,占5.56%,肺脓肿6例,占16.67%,上呼吸道感染6例,占16.67%,肺癌3例,占8.32%,X线征象两种或两种以上11例,占30.56%。结论单纯肺中下野结核易于误诊,通过X线影像特征能够有效地诊断不典型肺结核患者。