简介:β-glucanisoneofthemostimportantsourcesofcellwallinyeaststrains(Saccharomycescerevisiae).Itisnowknownthatβ-glucannotonlyexhibitsabroadspectrumofbiologicalactivitiesincludingimmune-modulating,anti-inflammatory,anti-cancer,andanti-agingproperties,butalsocanbeusedinfoodproductionasmoisturizer,dietaryfibers(DF)[1].Therefore,itisimperativetobreedyeaststrainswithhigherbiomassproductionandoptimizethefermentationprocess.Saccharomycescerevisiaeneedscarbonsourcesinbiomassaccumulation,butglucoseisexpensiveinindustrialfermentation[2].TheaimofthisstudyistoevaluatethedifferentcarbonsourcesonthegrowthofSaccharomycescerevisiae.
简介:Ithasbeenproposedthatfusionreactionsbetweenneutron-richlightnuclei,forexample24C,24Oand28Ne,maycontributetoachievingtheignitiontemperatureforexplosivecarbonburningprocessduringsuperbusrsts[1,2].Studiesoffusionreactionsinvolvingneutron-richnucleiarebeyondordinaryexperimentaltechniques,sincetheintensityofradioactivebeambecomelowforthesemeasurements[3].TheactivetargettechniqueusingTPC(TimeProjectionChamber),withpropertiesofmulti-sampling,highefficiencyandlowbackground,isasuitablesolutiontotheproblem.
简介:Broadband(1.6–18THz)terahertztime-domainspectroscopy(THz-TDS)andtime-resolvedterahertzspectroscopy(TRTS)wereperformedona54μmthickchalcogenideglass(As30Se30Te40)samplewithatwo-colorlaser-inducedairplasmaTHzsystemintransmissionandreflectionmodes,respectively.Twoabsorptionbandsat2–3and5–8THzwereobserved.TRTSrevealsanultrafastrelaxationprocessofthephotoinducedcarrierresponse,welldescribedbyarateequationmodelwithafiniteconcentrationofmid-bandgaptrapstatesforself-trappedexcitons.ThephotoinducedconductivitycanbewelldescribedbytheDrude–Smithconductivitymodelwithacarrierscatteringtimeof12–17fs,andweobservesignificantcarrierlocalizationeffects.Afastrefractiveindexchangewasobserved100fsbeforetheconductivityreacheditsmaximum,with2ordersofmagnitudelargeramplitudethanexpectedfortheopticallyinducedTHzKerreffect,indicatingthatfreecarriersareresponsibleforthetransientindexchange.