简介:Acompactammoniagassensorwithtwogaschambersisproposedinthispaper,whosecoresensingdeviceisaU-bendingmicroringresonator.Thewaveguidesofringpartandfeedbackpartinthisresonatoraremadeofsilicononinsulator(SOI)ridgewaveguidecoveredwithZnOnanocrystalswhicharesensitivetoammoniagas.Thesensorcanmeasuretwogroupsofgassamplessimultaneously.Bycomputersimulation,weobtaintheclearsensitivitycurvesoftwogaschambersinammoniasensorwhenthegasconcentrationincreasesfrom0to4‰.Thegasconcentrationsintwochamberscanbeobtainedfromoneoutputspectrum,whichsignificantlyreducesthematerialandtimeconsumption.
简介:Toimprovetheinitialcoulombicefficiencyandbulkdensityoforderedmesoporouscarbons,activeFe2O3nanoparticleswereintroducedintotubularmesoporechannelsofCMK-5carbon,whichpossesseshighspecificsurfacearea(>1700m2g-1)andlargeporevolume(>1.8cm3g-1).FineFe2O3nanoparticleswithsizesintherangeof57nmwerehighlyandhomogenouslyencapsulatedintoCMK-5matrixthroughammonia-treatmentandsubsequentpyrolysismethod.TheFe2O3loadingwascarefullytailoredanddesignedtowarrantahighFe2O3contentandadequatebufferspaceforimprovingtheelectrochemicalperformance.Inparticular,suchFe2O3andmesoporouscarboncompositewith47wt%loadingexhibitsaconsiderablystablecycleperformance(683mAhg-1after100cycles,99%capacityretentionagainstthatofthesecondcycle)aswellasgoodratecapability.Thefabricationstrategycaneffectivelysolvethedrawbackofsinglematerial,andachieveahigh-performancelithiumelectrodematerial.