简介:通过原位下的高压同步辐射X光衍射技术,对具有钙钛矿结构的La0.4Bi0.1Ca0.5MnO3中存在的Jahn-Teller畸变,进行了研究。实验表明在压力的作用下,样品中的畸变有所减小,超于理想的立方结构,并且在1.4GPa左右存在一个过渡相。
简介:Anumericalsimulationmodelfor252kVpuffercircuitbreakerisconstructed,byusingaprovencommercialcomputationalfluiddynamics(CFD)package,PHOENICS.Themodeltakesintoaccountthemovingpartsinthecircuitbreaker,turbulenceenhancedmomentumandenergytransport,radiationtransport.ThearcingprocessinaSF6puffercircuitbreakerwithtwohollowcontactsissimulatedunderdifferentconditions,andthesimulationresultsareverifiedwithexperimentalresults.Throughsimulation,thepressure,temperatureandvelocityinthearcquenchingchambercanbeobtained.Thesimulationmodelisalsocapableofpredictingtheinfluenceofdesignparametersvariationsonbreakerperformance,andcanthushelptoreducethenumberofshort-circuittestsduringthedesignstage.
简介:Anewrectangularpulsetriggergeneratorhasbeendevelopedwhichcangeneratetwo10kVpulseswitharisetimelessthan1ns,ajitterof0.2nsandawidthofabout10nsand40ns,respectively.Thisgeneratorusestwopolymer-foilswitchesand25ohmBlumleintransmissionlinescomposedoftwo-parallelstandardcoaxialcablesdischargingintotwo50ohmoutputcables.Thepulsewidthandthedelaybetweentwopulsescanbeadjustedbychangingthelengthofthecables.