简介:在这份报纸,我们在场supercooled上的大小浇的深无弹性的中子散布的结果(吵闹)在毛孔以内限制了(平均毛孔直径~20)经由大音阶的第五音胶化方法通过alkoxide先锋Tetra-Methyl-Ortho硅酸盐的水解作用和polycondensation获得的一个混乱吸水的硅石矩阵。实验在二温度被执行(250K和210K,即在supercooled的通常认为的liquidliquid转变限制了水前后)在有hydrationh~40%w/w的一件湿样品上,它足够高有充满水的毛孔但是对足够低避免水结晶化。7%也是的几乎干燥的样品ath~调查了测量硅石矩阵的贡献到散布信号的中子。这是众所周知的,吵闹大小在系统允许吝啬的动能的决心和氢原子的动量分发因此,允许研究人员探查supercooled的本地结构限制的水。获得的主要结果是在210K,氢平均数动能比在250K稍微高相等或平。这与最近建议在水里描述氢的动能的温度依赖的一个semiempirical泛音模型的预言是不一致的。这是新、很有趣的结果,它建议在210K,水氢比在250K经历一个更生硬的分子间的潜力。这与liquidliquid转变假设一致。
简介:Thedomesticrainwaterharvestingsystem(DRHS)isanimportantfreshwatersourceforZhoushan,Chinatomeetwaterdemands.AcomputermodelhasbeengeneratedtoanalyzetheperformanceoftheDRHSwithdifferentratiosofD/(AR)(waterdemand/averageannualcollectedrunoff)andS/(AR)(storagecapacity/averageannualcollectedrunoff).TheperformanceoftheDRHSwasanalyzedbymeansofthemodelsimulation,whichisdescribedbyitswatershortagerate(WSR)andwaterlossrate(WLR).Usingthedata,asetofdimensionlessdesigncalculationchartisintroduced.Whenthewaterdemandandrequirementofthedesignareknown,theestablishedchartcanbeusedtoeasilydeterminethestoragecapacityandcatchment(roofandothersurface)arearequiredtoachieveadesiredperformancelevel.
简介:动态或在biomolecules的玻璃转变对他们的工作重要。另外必要是在蛋白质土著人状态和展开的过程之间的转变。更好理解这些转变,我们使用Fourier变换越过一个宽温度范围学习含水的溶解酵素的震动的弯曲并且拉长的模式的红外线的光谱学。我们发现这些转变被在蛋白质和水和水之间联合的强壮的氢契约触发。更精确,我们证明在两个盒子中,水性质统治系统的进化。我们发现二典型温度是相关的:在限制的水的supercooled政体,fragile-to-strong动态转变发生在TL,并且在稳定的液体阶段,T*315瑡牥洠汯'虥N獥椠?桴?楦獲?票牤瑡潩?桳汥?
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简介:一张新奇相片催化反应堆被开发搬迁(从水的1,1二度(4-chlorophenyl)-2,2,2-trichloroethane)(DDT)。在反应堆,cenosphere被用来支持借助于大音阶的第五音胶化做的TiO2电影。因为cenospheres与TiO2,是涂的,他们的比重稍微从原版被增加0.6∼0.8到0.8∼0.9,以便他们能在水里被推迟。与bubbler的混合操作,在反应堆的水处于一个使流体化得好的状态。反应堆的底部是一张沙过滤器床,它能被用来阻止光催化剂被失去。反应堆的一个数学模型在二个主要有影响的因素被开发了:紫外(紫外)轻紧张和光催化剂集中。与如此的一个模型一起,反应堆能更相当被设计。
简介:Theresultsonadissociationbehaviorofpropanehydratespreparedfrom'drywater'andcontainedunreactedresidualwaterintheformoficeinclusionsorsupercooledliquidwater(watersolutionofgas)werepresentedfortemperaturesbelow273K.Thetemperaturerampingorpressurereleasemethodwasusedforthedissociationofpropanehydratesamples.Itwasfoundthatthemechanismofgashydratedissociationattemperaturesbelow273Kdependedonthephasestateofunreactedwaterinthehydratesample.Gashydratesdissociatedintoiceandgasiftheiceinclusionswereinthehydratesample.Thesamplesofpropanehydrateswithinclusionsofunreactedsupercooledwateronly(withouticeinclusions)dissociatedintosupercooledwaterandgasbelowthepressureofthesupercooledwater-hydrate-gasmetastableequilibrium.
简介:Wateroxidation,asamandatoryreactionofsolarfuelsconversionsystems,requirestheuseoflightabsorberswithelectronicpropertiesthatarewellmatchedwiththoseofthemulti-electroncatalystinordertoachievehighefficiency.Molecularlightabsorbersofferflexibilityinfinetuningoforbitalenergetics,andmetaloxidenanoparticleshaveemergedasrobustoxygenevolvingcatalysts.Hence,thesematerialchoicesofferapromisingapproachforthedevelopmentofphotocatalyticsystemsforwateroxidation.However,efficientchargetransfercouplingofmolecularlightabsorbersandmetaloxidenanoparticlecatalystshasprovenachallenge.Recentnewapproachestowardtheefficientcouplingofthesecomponentsbasedonsyntheticdesignimprovementscombinedwithdirectspectroscopicobservationandkineticevaluationofchargetransferprocessesarediscussed.
简介:Directphotontochemicalenergyconversionusingsemiconductor–electrocatalyst–electrolyteinterfaceshasbeenextensivelyinvestigatedformorethanahalfcentury.Manystudieshavefocusedonscreeningmaterialsforefficientphotocatalysis.Photocatalyticefficiencyhasbeenimprovedduringthisperiodbutisnotsufficientforindustrialcommercialization.Detailedelucidationonthephotocatalyticwatersplittingprocessleadstoconsecutivesixreactionstepswiththefundamentalparametersinvolved:Thephotocatalysisisinitiatedinvolvingphotophysicsderivedfromvarioussemiconductorproperties(1:photonabsorption,2:excitonseparation).Thegeneratedchargecarriersneedtobetransferredtosurfaceseffectivelyutilizingtheinterfaces(3:carrierdiffusion,4:carriertransport).Consequently,electrocatalysisfinishestheprocessbyproducingproductsonthesurface(5:catalyticefficiency,6:masstransferofreactantsandproducts).Successfulphotocatalyticwatersplittingrequirestheenhancementofefficiencyateachstage.Mostcritically,afundamentalunderstandingoftheinterfacialphenomenaishighlydesiredforestablishing'photocatalysisbydesign'concepts,wherethekineticbottleneckwithinaprocessisidentifiedbyfurtherimprovingthespecificpropertiesofphotocatalyticmaterialsasopposedtoblindmaterialscreening.Theoreticalmodelingusingtheidentifiedquantitativeparameterscaneffectivelypredictthetheoreticallyattainablephoton-conversionyields.Thisarticleprovidesanoverviewofthestate-of-the-arttheoreticalunderstandingofinterfacialproblemsmainlydevelopedinourlaboratory.Photocatalyticwatersplitting(especiallyhydrogenevolutiononmetalsurfaces)wasselectedasatopic,andthephotophysicalandelectrochemicalprocessesthatoccuratsemiconductor–metal,semiconductor–electrolyteandmetal–electrolyteinterfacesarediscussed.
简介:Ironoxidenanoparticles(FeO_xNPs,5–30nmsize)preparedvialaserablationinliquidweresupportedontoIndiumTinOxideconductiveglassslidesbymagnetophoreticdeposition(MD)technique.TheresultingFeOx@ITOelectrodesarecharacterizedbyalowamountofironcoverageof16–50nmol/cm~2,andshowelectrocatalyticactivitytowardswateroxidationinneutralphosphatebufferpH7with0.58VoverpotentialandquantitativeFaradaicefficiencytowardsoxygenproduction.XPSanalysisontheoxygenregionoftheFeO_xfilmsrevealsasubstantialhydrationofthesurfaceaftercatalysis,recognizedasacrucialsteptoaccessreactivity.
简介:Nanostructuredironoxyhydroxide(FeOOH)thinfilmshavebeensynthesizedusinganelectrodepositionmethodonanickelfoam(NF)substrateandeffectofairannealingtemperatureonthecatalyticperformanceisstudied.Theas-depositedandannealedthinfilmswerecharacterizedbyX-raydiffraction(XRD),X-rayphotoelectronspectroscopy(XPS),fieldemissionscanningelectronmicroscopy(FE-SEM)andlinearsweepvoltammetry(LSV)todeterminetheirstructural,morphological,compositionalandelectrochemicalproperties,respectively.Theas-depositednanostructuredamorphousFeOOHthinfilmisconvertedintoapolycrystallineFe2O3withhematitecrystalstructureatahightemperature.TheFeOOHthinfilmactsasanefficientelectrocatalystfortheoxygenevolutionreaction(OER)inanalkaline1MKOHelectrolyte.Thefilmannealedat200°Cshowshighcatalyticactivitywithanonsetoverpotentialof240mVwithasmallerTafelslopeof48mV/dec.Additionally,itneedsanoverpotentialof290mVtothedrivethecurrentdensityof10mA/cm2andshowsgoodstabilityinthe1MKOHelectrolytesolution.
简介:Thehighrepetitionrate10J/10nsYb:YAGlasersystemanditskeytechniquesarereported.Theamplifiersinthissystemhaveamulti-passV-shapestructureandtheheatintheamplifiersisremovedbymeansoflaminarwaterflow.Inthemainamplifier,thelaserisfour-pass,andanapproximately8.5J/1Hz/10nsoutputisachievedintheprimarytest.Thefar-fieldoftheoutputbeamisapproximately10timesthediffractionlimit.Becauseofthehigherlevelsofamplifiedspontaneousemission(ASE)inthemainamplifier,theoutputenergyislowerthanexpected.Attheendwediscusssomemeasuresthatcanimprovethepropertiesofthelasersystem.