简介:AnovelcrystalcharacterizationinstrumenthasbeenbuiltupinwhichacombinationofX-raymultiplediffractionandX-raytopographyisappliedtoenablingthecross-correlationbetweenmicro-crystallographicsymmetryanditsspatialdependenceinrelationtolatticedefects.Thisfacilityisusedtoexamine,inaselfconsistentmanner,growthsector-dependantchangestoboththecrystallographicstructureandthelatticedefectsassociatedwiththeactionofhabit-modifyingadditivesinanumberofrepresentativecrystalgrowthsystems.Inaddition,thenewinstrumentcanbeusedtoprobemicro-crystallographicaspects(suchasdistortiontocrystalsymmetry)andrelatetheseinaspatiallyresolvedmannertothecrystaldefectstructureincrystalsdopedwithknownhabitmodifiers.
简介:Non-smallcelllungcancer(NSCLC)accountsfor85%oflungcancer,whichistheleadingcauseofdeathinlungcancerpatient.RoutinetreatmentofNSCLCcannoteffectivelychangethesurvivalrateofpatients,oneimportantreasonistheincreasedradioresistanceoftumorcellsafterconventionalradiotherapy.
简介:ThelocalstructuresoftheimmiscibleFe100-xCuxalloys(x=0,10,20,40,60,80and100)producedbymechanicalalloyinghavebeeninvestigatedbyXAFS.FortheFe100-xCux(x≥40)solidsolutions,thelocalstructuresaroundFeatomschangefrombccstructuretofcconeandtheCuatomsmaintaintheoriginalcoordinationgeometryaftermillingfor160hours.Onthecontrary,thelocalstructuresaroundCuatomsinbothofFe80Cu20andFe90Cu10alloysappearatransitionfromfcctobccstructure.WefoundthattheDebye-wallerfactorσoffccFe-CuphaseislargerthanthatofbccF-Cuphase,andtheσ(0.099A°)aroundFeatomsislargerthanthat(0.089A°)ofCuintheFe100-xCux(x≥40)solidsolutions,ThissuggeststhatthemechanicallyalloyedFe100-xCuxsupersaturatedsolidsolutionisnotahomogeneousalloy,andconsistsofFe-richandCu-richregionsforvariouscompositions.Apossiblemechanismforbcc-to-fccandfcc-to-bccchangesinFe100-xCuxsolidsolutionsisdiscussedinrelationtotheinterdiffusionandtransitioninducedbytheballmilling.
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简介:Zr1-xTixCo(x=0,0.1,0.2,0.3)alloyswerepreparedbyarc-meltingmethodandtheeffectofTisubstitutiononhydrogenstoragepropertieswasstudiedsystematically.Hydrogendesorptionpressure-composition-temperature(PCT)measurementswerecarriedoutusingSievert’stypevolumetricapparatusforZrCo(at473K,573Kand673K)andZr1-xTixCoalloys(at673K),respectively.ProductsafterdehydrogenationwerecharacterizedbyX-raydiffraction(XRD).Inaddition,thekineticsofZr1-xTixCohydridewasinvestigatedat473Kand673K,respectively,underhydrogenpressureof5MPa.ResultsshowedthatTisubstitutionforZrdidnotchangethecrystalstructureofZrCophase.Withtheincreaseoftemperaturefrom473Kto673K,theextentofdisproportionationforZrCoalloyincreased.WithTicontentincreasingat673K,thedesorptionequilibriumpressureofZr1-xTixCo-H2systemselevatedandthedisproportionationreactionofZr1-xTixCoalloyswasinhibitedeffectively.TisubstitutiondecreasedthekineticsrateandtheeffectivehydrogenstoragecapacityofZr1-xTixCoalloysslightly.Generallyspeaking,itwasfoundthatZr0.8Ti0.2Coalloyhadbetteranti-disproportionationpropertywithlessdecreaseofeffectivehydrogenstoragecapacitywhichwasbeneficialtotritiumapplicationintheInternationalThermonuclearExperimentalReactor(ITER).
简介:BymeansoftheintensitytheoryofX-rayscatteringandthetwo-phaseconceptofhighpolymer,thebasicformulaofthecrystaUinityinblockcopolymershasbeenproposedafterthecorrectionsofatomic,temperature,absorption,Lorentzandpolarizationfactor.Applicationofthismethodtodifferenttypepoly(oxyethylene-styrene)blockcopolymersandthesametypeblockcopolymerswithdifferentEOcontentsindicatesthatthecrystallinityinpoly(oxyethylene-styrene)blockcopolymersincreaseswiththeincreaseoftheEOcontentanddecreasesintheorder:PEO-PS-PEO>PEO-PS>PS-PEO-PS.