简介:ThecopolymerswereformedbythegraftcopolymerizationofPVCwithacrylicrareearth.TheprincipleandmethodofthegraftcopolymerizationofPVCandacrylicrareearthwerediscussed.ThegraftcopolymerswerecharacterizedbyFT-IRspectraandscanningelectronmicroscope(SEM).Thethermalstabilityofthegraft-copolymerswasstudiedbythermogravimetricanalysis(TG).Theexperimentresultsshowthatthethermalresistanceandtoughnessofthegraftcopolymersareobviouslyenhanced.
简介:Thenanosizedparticlematerialsofdoped-TiO2withY2O3werepreparedbymeansofsol-geltechniqueforuseinelectrorheological(ER)fluids,andtheircrystalstructuresweremeasuredbyX-raydiffraction(XRD)analysis.TocomparewiththepureTiO2,adistinctenhancementintheshearstressunderdcelectricfieldwasfoundbyusingsuchmaterials.Thiscanbeexplainedbytheincreaseofthedielectriclossanddielectricconstantatlowfrequency.TheeffectsofthecrystalstructureoftheparticlesonthedielectricpropertyandERperformanceofmaterialswereinvestigated.
简介:TheNd60Fe20Al8Co10B2alloywaspreparedbysuctioncastingofthemoltenalloyintoacoppermoldunderargonatmosphere.Themicro-structuralandmagneticpropertychangesintheNd60Fe20Al8Co10B2alloyduringcrystallizationwereinvestigatedbyX-raydiffraction(XRD),differentialscanningcalorimetry(DSC),scanningelectronmicroscope(SEM)andthevibratingsamplemagnetometer(VSM).TheprecipitationandNd-richandFe-richphaseshavenosignificanteffectontheintrinsiccoercitityforNd60Fe20Al8Co10B2alloyannealedbelow723K.However,thegrowthofFe-richphasedecreasesthesaturatemagnetizationandremanenceofthealloy.Thehardmagneticbehaviorisdisappearedwhenthealloyisfullycrystallized.
简介:TheLa3+-loadedadsorbentwaspreparedbythereactionbetweenLa3+andethanolamine-modifiedvegetabletannicextract,totreatF--containingwastewater.TheproblemsofheavycolorcausedbyvegetabletannicextractandofturbiditycausedbyreactionbetweenLa3+andF-weresolved.Whenotherconditionswerenotchanged,pH,temperature,stirringtime,anddosewerechangedrespectivelyandtheadsorbancewastestedrespectively.Theresultsshowthatthisadsorbentpossesseshighsaturatedadsorptivecapacity(18.86mg·g-1)whenpHis5~6,T≤80℃,0.2gdosage,and180minagitatingtime,andtheadsorbancereachesthehighest(98.5%).Theadsorbentcanbeeasilyregeneratedwith0.5mol·L-1NaOHatpH12.
简介:Thecomplexofneodymiumchloridelowerhydratewithdiethylammoniumdiethyldithiocarbamate(D-DDC)wassynthesizedconvenientlyinabsolutealcoholanddryN2atmosphere.ThetitlecomplexwasidentifiedasEt2NH2[Nd(S2CNEt2)4]bychemicalandelementalanalysesandthebondingcharacteristicsofwhichwascharacterizedbyIR.TheenthalpiesofsolutionofneodymiumchloridehydrateandD-DDCinabsolutealcoholat298.15Kandtheenthalpieschangeofliquid-phasereactionofformationforEt2NH2[Nd(S2CNEt2)4]atdifferenttemperaturesweredeterminedbymicrocalorimetry.Onthebasisofexperimentalandcalculatedresults,threethermodynamicparameters(theactivationenthalpy,theactivationentropyandtheactivationfreeenergy),therateconstantandthreekineticparameters(theapparentactivationenergy,thepre-exponentialconstantandthereactionorder)ofliquid-phasereactionofformationwereobtained.Theenthalpychangeofthesolid-phasetitlereactionat298.15Kwascalculatedbyathermochemicalcycle.
简介:Anincubationstudywasperformedtoelucidateexogenousrareearthelements(RE)influencingonmicrobialbiomass,microbialecophysiologicalparameterscmic/corg,metabolicquotientqCO2andrespiratoryrateinrelationtotemporalavailabilityinpaddysoil.Sixsampleswereaddeddifferentconcentrationsbetween0and2000mg*kg-1REEsinsoil.ResultsshowthatexogenousREhaveslightstimulativeeffectsonmicrobialindicesinpaddysoilatlowconcentrationintheearlystageafteraddingRE,whilehavinginhibitoryeffectsathighconcentration.TheinhibitionisstrengthenedwithincreasingREconcentrationandisweakenedwithincreasingincubationtime.PrincipalcomponentanalysisoftheBIOLOGdataindicatesthatmicrobialcommunitystructureshavechanged,carbonsourcesconsumptionofmicroorganismsinpaddysoilbecomesmuchmorerapidafter8weeks,andunderREstress,thechangeofmicrobialcommunitystructuresisalong-termeffect.
简介:DistributionandaccumulationofNd,anditseffectonsecretionofprogesteroneinmicewerestudiedusingradioisotopetracer(147Nd)technique.Followingsingleintraperitonealadministrationofneodymiumtracedwith147Ndatadoseof200mg*kg-1,unevendistributionoftheradioactiveNdoccurredinvarioustissuesandorgans.Muchamountof147Ndaccumulatesinthebone,andtheresidueincreaseswiththelapseoftime.Someamountofradioactivitywasalsodetectedineyes,bloodandbrain,buttheaccumulationdecreasedwiththetimeduetoexcretionandre-distributioninmice.Incomparisonwithcontrols,concentrationofprogesteroneisfoundtobesignificantlylowerintheserumofadministeredmice,indicatingasignificantlyinhibitoryeffectofNdonsecretionofprogesterone.