简介:AnewcompoundK6Ti0.67Nb15.33O42waspreparedforthefirsttimebysolidstatereactioninK2O-Ni2O3-Nb2O5ternarysystem.Thenewcompoundwascharacterizedbyelectronprobe,X-raypowderdiffractionandDTA.TheresultofX-raypowderdiffractionshowsthatK6Ti0.67Nb15.33O42crystallizesthehexagonalsystemwithunitcellparametersa=9.1341(5)A,c=12.090(1)A.andspacegroupP62/mcm(193).
简介:Nearlysingle-phaseandpolycrystallinecharge-density-wavecompoundK_(0.3)MoO_3havebeenpreparedbyusingasimplemethod.Inthiswork,K_2CO_3andMoO_3wereusedasstartingmaterialsandreactedbyhotisostaticpressing(HIP)sintering.TheproductisnearlysinglephaseK_(0.3)MoO_3determinedbyX-raypowderdiffraction(XRD)andenergydispersivespectroscopy(EDS).MeasurementoftemperaturedependenceofresistivityrevealsthatthetransportpropertyofpolycrystallineK_(0.3)MoO_3obviouslydiffersfromthatofsinglecrystalduetothegrainboundariesandtheanisotropicstructureinthiskindofcompound.
简介:AseriesofCd1-xZnxS/K2La2Ti3O10compositesweresynthesizedviaasimpleco-precipitationmethod.ThepreparedsampleswerecharacterizedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM),X-rayenergydispersivespectroscopy(EDX),ultraviolet-visiblediffusereflection(UV-Vis),X-rayphotoelectronspectroscopy(XPS)andphotoluminescence(PL)measurements.ThecompositestructuresconsistedofCd1-xZnxSnanoparticlesevenlydistributedonthesurfaceofK2La2Ti3O10.TheabsorptionedgeofK2La2Ti3O10shiftedtothevisiblelightregionuponintroductionoftheCd1-xZnxSnanoparticles.Thephotocatalyticactivitiesofthecatalystswereevaluatedbyhydrogenproductionundervisiblelightirradiation.ThepreparedCd0.8Zn0.2S(30wt%)/K2La2Ti3O10exhibitedhigherphotocatalyticactivity,evolving6.92mmol/gH2undervisiblelightirradiationfor3h.ThepromotedphotocatalyticactivityofthecompositeswasattributedtothesynergisticeffectbetweenCd1-xZnxSandK2La2Ti3O10,whichresultedinenhancedseparationofphotogeneratedelectronsandholes.
简介:埃克森美孚化工计划自8月18日开始,提高美洲地区PP售价,幅度为2美分/磅。埃克森美孚向客户致信,称提价产品包括PP均聚物、共聚物以及无规共聚物,丙烯月度合同价的任何变化都不会对提价计划生产影响。同时,布拉斯科美洲公司也宣布自8月1日起,其PP价格将上涨4美分/磅。利安德巴塞尔与埃克森美孚一样,涨价目标同为2美分/磅。而道达尔石化宣布自7月7日起,PP涨价4美分/磅。市场人士指出,多重生产问题导致供应紧张,这是提价的主要原因。市场消息称,生产商宣布的涨幅极可能是针对未签订合同的现货买家和经销商,年底也有可能针对合同买家进行价格调整。