简介:ThetemperaturedependenceofresistivityρofYSZdopingcompositeof(1-x)La0.67Ca0.33MnO3+xYSZandY2O3dopingcompositeof(1-y)La0.67MnO3+yY2O3isinvestigated,respectively,inatemperaturerange77-300K,wheretheYSZrepresentsyttria-stabilizedzirconia(8mol%Y2O3+92mol%ZrO2).ExperimentalresultsshowthattheYSZdopinglevelhasimportanteffectsonboththemetal-insulator(M-I)transitiontemperaturesandzerofieldresistivityofthecompositesof(1-x)La0.67Ca0.33MnO3+xYSZ.However,theY2O3dopinglevelhaslittleeffectontheM-Itransitiontemperaturesandthezerofieldresistivityof(1-y)La0.67Ca0.33MnO3+yY2O3onlyincreasesslightly.Thedifferencebetweenthetwotypesofcompositesmaymainlyresultsfromthedifferentdistributionofhighresistancephasesatthegrainboundariesand/orsurfacesofLa0.67Ca0.33MnO3grainsratherthanthesubstitutionofLa^3+ionswithY^3+ions.
简介:InsituhighpressureenergydispersiveX-raydiffractionmeasurementsonlayeredperovskite-likemanganateCa3Mn2O7underpressuresupto35GPahavebeenPerformedbyusingdiamondanvilcellwithsynchrotronradiation.Theresultsshowthatthestructureoflayeredperovskite-likemanganateCa3Mn2O7isunstableunderpressureduetotheeasycompressionofNaCl-typeblocks.ThestructureofCa3Mn2O7underwenttwophasetransitionsunderpressuresintherangeof0-35GPa.Onewasatabout1.3GPawiththecrystalstructurechangingfromtetragonaltgoorthorhombic.Theotherwasatabout9.5GPawiththecrystalstructurechangingformorthorhombicbacktoanothertetragonal.
简介:Ca3Y2(BO3)(4):Eu3+黄磷被高温度solid-statereaction方法综合,并且光特征被调查。排放光谱在相应于电的dipoleD-5(0)的613和621nm展出二强壮的红排出物在365nm刺激下面的Eu3+的-F-7(2)转变,原因是Eu3+代替forY3+在Ca3Y2(BO3)(4)的水晶结构占据非中心对称的位置。为613nm的Theexcitation光谱显示黄磷能是有效地激动的由紫外(紫外)(254nm,365nm和400nm)并且蓝色(470nm)光。Ca3Y2(BO3)(4)的排放紧张上的Eu3+集中的效果:Eu3+黄磷被测量,排放紧张与增加Eu3+集中增加的结果表演,然后减少。Ca3Y2(BO3)(4)的CIE颜色坐标:Eu3+黄磷是(0.639,0.357)在15mol%Eu3+。
简介:TheAlkalineThermalTreatment(ATT)ofbiomassisoneofthefewbiomassconversionprocessesthathasapotentialforBECCS(bio-energywithcarboncaptureandstorage).Combiningin-situcarboncapturewithcreatesacarbon-neutralprocessthathasthepotentialtobecarbon-negative.Thisstudyhasshownthattheconversionofcellulosetosuppressedcanbeachievedthroughthereformingofgaseousintermediatesinafixedbedof10%Ni/ZrO2.Reformingoccursatlowtemperatures≤773K,whichcouldallowforimprovedsustainability.