简介:Sr1.995–1.5xGdxSiO4:0.005Eu2+phosphorserieswithx=0–0.08molfornear-ultravioletwhitelight-emittingdiodes(NUVw-LEDs)weresynthesizedviasolid-statereactionmethod.XRDprofilepatternandrefinementresultsdemonstratedthatdopingGd3+ionsresultedinthephasetransformation(β-Sr2SiO4→α’-Sr2SiO4).Thephotoluminescencespectrumofthesamplewithx=0moldisplayedtwoemissionpeakscenteredat470and525nm.Thetwo-peakspectrabecameone-peakspectrawiththeGd3+concentrationincreasing.Actually,thefittingresultsdemonstratedthattheone-peakspectrawerestillcomposedoftwosingleemissionspectra.ThephotoluminescenceintensitywasimprovedandtheCIEchromaticitycoordinateswereadjustedviadopingGd3+.
简介:TheCa_2SiO_4:Dy~(3+)phosphorwassynthesizedbythehightemperaturesolid-statereactionmethodinair.TheemissionspectrumofCa_2SiO_4:Dy~(3+)phosphorshowsseveralbandsat486,575,and665nmunderthe365-nmexcitation.TheeffectsofLi~+,Na~+,andK~+ontheemissionspectrumofCa_2SiO_4:Dy~(3+)phosphorwerestudied,TheresultsshowthattheemissionspectrumintensityisgreatlyinfluencedbyLi~+,Na~+,andK~+.Thechargecompensationconcentrationcorrespondingtothemaximumemissionintensityisdifferentwithdifferentchargecompensations.
简介:Thegreenlong-after-glowluminescencefromTb3+-dopedSr2SiO4phosphors,whicharesynthesizedbythehightemperaturesolidstatereactioninareductiveatmosphere,isobservedinthispaper.Theresultsshowthatunderultravioletexcitation,theobtainedphosphorsproduceanintensegreen-lighting-emissionfromtheTb3+,andthegreen-lightinglongafter-glowluminescencerelatedtoTb3+canlasthalfanhouraftertheirradiationsourcehasbeenremoved.Moreover,theeffectsofco-dopingLi+,Dy3+,Er3+,Gd3+,andYb3+withTb3+onthedecaypropertiesandthermoluminescencepropertiesareinvestigatedtoconfirmthelong-after-glowmechanism.
简介:SZorbadsorptivedesulfurizationtechnologyisofgreatsignificanceontheproductionofcleangasolineinChina,buttheformationofZn2SiO4duringtheoperationinsorbentswouldbringforthnegativeimpactsonthedesulfurizationperformanceandthestabilityoftheprocessingunit.Byusingthein-situTPO,XRD,andIRtechniquestostudythemechanismofZn2SiO4formationunderoperatingconditions,itwasfoundthatthecoexistenceofacidandhydrothermalconditionscouldacceleratetheformationofZn2SiO4.Moreover,thestudyofZn2SiO4inhibitionmethodindicatedthatthedecreaseofoxygenconcentrationinregenerationgaswouldinhibittherateofZn2SiO4formation,andtheregenerationofZnSwouldtakeplaceinamildregenerationcondition.
简介:摘要纳米纤维素(NCC)是一种新型的纳米材料,因其表面羟基较多,水溶性较差,在生物医药应用方面受到局限。将NCC表面的羟基进行衍生化,首先将NCC碱化,然后用醚化试剂3-氯-2-羟丙基三甲基氯化铵醚化生成季铵化NCC;并对其作为缓释载体进行了考察,将其与镇痛模型药物在适量的条件下孵育形成纳米粒子,对该纳米粒子进行体外释放及动物体内的镇痛活性实验。衍生的季铵化NCC由于表面的羟基减少,氢键作用减弱,水溶性增加;其形成的纳米粒子可在体外缓慢释放,释放率为80%左右;在动物体内具有镇痛活性,持续时间比模型药物长1h。本实验说明季铵化NCC不仅具有很好的水溶性,将其作为药物载体拥有良好的缓释能力。
简介:摘要:本研究致力于探讨微纳米纤维素(CNF)在环保食品卡纸中的应用,特别是其通过淋膜技术提高纸张防油性和机械性能的潜力。通过使用Tempo氧化均质法制备的CNF,我们研究了不同淋膜量对食品卡纸性能的影响,包括防油性、防热油性和防溶剂性。实验结果表明,CNF能显著提高卡纸的阻隔性能和物理强度,尤其在对抗油脂和热油的应用中表现出色。此外,我们还分析了PLA/CNF复合淋膜的制备过程及其在食品安全包装中的应用潜力。研究结果对发展新型环保包装材料具有重要意义。