简介：Thevolumesperoxygenofsomesilicatemeltshavebeencalculatedandthencomparedwiththoseofsilicateglasses.Itissuggestedthatthevolumeofasilicatemeltcanbedividedintotwoparts.Oneiscontributedbythesilicon-oxygennetworkandtheotherbythe“oxides”.VariationpatternsofVPOssuggestthatthevolumeoftheSi-Onetworkgenerallyremainsunchangedandtheexpansionofthemeltiscausedmainlybythelocatexpansionofthe“oxides”.ItisfurtherproposedthattheradiusofO^2-showslittlevariation,instrikingcontrasttotheradiusofcations.Themechanismgoverningtheexpansionisdiscussedindetail.

简介：硅(Si)经由钙硅酸盐的申请被供应了到植物到土壤；然而，因为它的低溶解度，钙硅酸盐的高剂量被要求。Nanoparticles能减少Si剂量并且被用于播种沟。这研究调查了液体Si来源的效果，即，高度可溶的硅酸盐(115.2gL1Si和60.5gL1Na2O)并且nanosilica(<200nm)，在Si上，由米饭的举起种，植物木质化，植物C:N:Pstoichiometry，植物生理学，和谷物在greanhousecondistions下面用Oxisol让步。处理包括了nanosilica和可溶的硅酸盐的申请到在0，605，1210，和2420g的Si剂量播种沟哈1。植物举起和处理效果被测量累积，生理的特征，和谷物米饭产出的C和木质素内容，Si，N，和P评估。在标志叶子的硅石身体和非结晶的硅石的免职用扫描电子显微镜学被分析。液体Si的申请在与控制的关系在米饭增加了Si累积47.3%(0g哈1Si)，不管Si，来源使用了。Nanosilica申请增加了叶木质素内容112.7%什么时候与那相比在控制。硅中等影响了网C吸收(增加了1.83%)并且蒸发率(增加了48.3%)；然而，Si影响了既不植物生长也不米饭的谷物产量。这些结果被关於生命或不能生活的应力的缺乏在实验期间在米饭植物解释。就我们的知识而言，在巴西农业，这在植物营养上作为Si化肥和它的效果是nanosilica的使用上的第一份报告。这研究提供米饭植物吸收并且积累nanoparticles的证据；然而，进一步的研究被要求在另外的植物种类调查nanoparticles的使用。

简介：Bonedefectisoneofthemostcommondiseasesinclinic.Existingtherapeuticapproacheshaveencounteredmanyproblems,suchaslackofautogenousallogeneicboneandimmunologicalrejectiontoallogeneicimplant.Synthetichydroxyapatite（HA）providedsolutionsforbonerepair,sincetheHAisthemaininorganiccomponentofanimals＇bone.AlthoughHAhasgoodbiocompatibility,butonlythelimitedosteogeniccapability,whichisofsignificanceformodernbonerepairmaterials.Siisanessentialtraceelementinbonetissue,andithasbeendemonstratedtobeabletopromoteboneformation.Therefore,silicate-dopedhydroxyapatite（Si-HA）mayserveasapromisingmaterialforbonerepair,andpromoteboneregenerationintherepair.ThecurrentreviewdiscussesdevelopmentofSi-HA,focusingonitspreparationandcharacterization,invitroandinvivoevaluationsofthematerial,positiveeffectofSi-HAonpromotingboneformationinclinicalapplications,andmolecularmechanisminvestigationofsuchpromotiveeffect.

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简介：Viscosityofsoda-lime-silicateglassdopedwithrareearthoxides(Pr6O11,Eu2O3,Yb2O3)wasinvestigatedbytherotatingcrucibleviscometer,themeltingtemperatureandactivationenergyforviscousflowofthestudiedmeltwerederivedonthebasisoftheArrheniusEquation,thecoefficientofthermalexpansion,glasstransitiontemperatureanddilatometricsofteningtemperaturewerealsodeterminedwithdilatometry,inordertorevealtheeffectsofrareearthelementsonthebehaviorofsoda-lime-silicateglass.Theresultsshowedthatintroductionofrareearthoxidesdecreasedtheviscosityofsoda-lime-silicateglassandmeltingtemperatureofcorrespondingmelt,increasedcoefficientofthermalexpansionofsoda-lime-silicateglass.Theglasstransitiontemperature,dilatometricsofteningtemperature,andmeltingtemperatureofsoda-lime-silicateglassdopedwithrareearthoxidesincreasedwithincreasingcationicfieldstrengthofcorrespondingrareearthions.

简介：Inthispaper,thedispersionandnucleationbehaviorofultrafineparticlesofsilicaandlayeredsilicate(LS)inpoly(ethyleneterephthalate)(PET)matrixareinvestigatedandcharacterizedbyTransmissionElectronMicroscopy(TEM),WideAngleX-rayDiffraction(WAXD),DynamicScanningCalorimetry(DSC),andAtomicForceMicroscopy(AFM).ThesolidprecursorsbasedonsilicaandLSaresuggestedoriginallyforpreparingnanocompositeswithgooddispersionmorphology.Resultsshowthattheinitialsub-micron(1000～500nm)LSparticlesareexfoliatedordispersedintonanometer-scaleparticles(30～70nm)duringtheirpolymerizationwithPETmonomers.Thesedispersednanoparticlesformanorderedmorphologyintheirnucleationandgrowthduringannealingnanocomposites.DSCpatternsrevealthatthedoublemeltingpeaksofannealedPET-LSnanocompositesdisappear,whiletheyhaveshrunkeninPET-silicaones.ThesefindingsstronglydemonstratethatthedispersednanoparticlesacceleratethecrystallizationofPET.ThedispersedLSparticleshavehigherpercolationandnucleationperformancethanthoseofsilica.Thehomogeneousdistributionmorphologyofultrafineparticlesiseasilyobtainedbycontrollingtheloadoftheircorrespondingprecursors.SuchadispersionobviouslyimprovesPETpropertiesinthatitsheatdistortiontemperature(HDT)increasesfrom76℃to103℃,andcrystallizationincreases2～4timesmorethanthatofPET.Especially,thenanocompositefilmskeepthemselvestransparentwhenparticleloadiswithin2wt.%thoughthereare3wt.%orsoofagglomeratedparticlesinthenanocomposites.

简介：Sm3+dopedsodalimesilicateglassesco-dopedwithAs2O3werepreparedandcharacterisedbymeasuringtheirabsorptionspectrainUV-VIS/NIRregionsandluminescencespectrainthevisibleregion.Judd-Ofeltintensityparameters,Ωλ,wereevaluatedfromthemeasuredintensifiesofthevariousabsorptionbands.ΩλparametersoftheseglasseswerecomparedwiththeΩλparametersofotherreportedSm3+glassestostudythebondingenvironmentsurroundingtheSm3+inthepresentglasses.Presenceof[AsO4]3-tetrahedrainthesecondcoordinationspherearoundthecentralSm3+ionmadetheseglasseslesscovalentascomparedtootheroxideglassesbuttheratioΩ4/Ω6ofthe～1.83indicatedthemtobefairlystable.WiththehelpofΩλparametersandluminescencedataforvariousemissionlines,radiativepropertiesfordifferentemissionlineswerecalculated.Thevaluesofradiativepropertiesindicatedthat4G5/2→6H7/2and4G5/2→6H9/2transitionsresponsiblefororangeluminescencemightbeusedinthedevelopmentofmaterialsforLED'sandotheropticaldevicesinthevisibleregion.

简介：ThisworkstudiedthecharacteristicsofSiO2distributionandstructureofsilicatephasesinMgO-ZrO2compositessynthesizedbyrawmaterialsoflightfiredmagnesitendzircon,Theresultsindicatethat30wt%-40wt%SiO2contentinthesystemisexistedintheformofcrystallineofforsterite(M2S),theremainderingofSiOcontent(60wt%0-70wt%)isexistedintheglassphase,Thechemicalcompositionofglassphaseiswellagreedwiththechemicalcompositionofmonticellite(CMS).

简介：Weproduceamaximum1.45Wlaseroutputat1064nmusinganeodymium-dopedsilicateglassfiberthathasarectangularcorewithdimensionsof~6.3μm×31.5μm.Themeasureddivergenceanglesoftheoutputlaserintwodimensionsare3.22°and1.76°,respectively.Theoutputpowerisstableandlimitedonlybytheavailablepumppower.

简介：Er/Ybco-dopedborate-silicateglasseswithvariousYbconcentrationswerefabricatedbyhigh-temperaturesolid-reactionmethod.Thephotoluminescencespectraaround1.55μmandthevisibleupconversionspectraweremeasured.TheradiativelifetimeofEr-4I13/2,com-paredwiththemeasuredone,wasobtainedbyJudd-Ofelttheorybasedontheabsorptionspectra.ArateequationmodelforEr/Ybco-dopedsystemhasbeenestablishedbasedonthedataobtainedfromthemeasurements,includingtheabsorptionandemissio...

简介：Inthispaper,wepresenttheluminescentpropertiesofTm3+∕Ho3+co-dopednewglass.Aseriesofsilicategermanateglasswaspreparedbytheconventionalmelt-quenchingmethod.IntheTm3+∕Ho3+co-dopedsilicategermanateglass,astrongemissionof2μmoriginatingfromtheHo3+:5I7→5I8transitioncanbeobservedunderconventional808nmpumping.Thecharacteristictemperatures,structure,andabsorptionspectrahavebeenmeasured.TheradiativepropertiesofHo3+inthepreparedglasswerecalculated.TheemissioncrosssectionofHo3+ionstransitioncanreach4.78×10-21cm2around2μm,andtheFWHMisashighas153nm.TheenergytransferefficiencybetweenHo3+andTm3+hasalargevalue（52%）,whichindicatestheTm3+∕Ho3+co-dopedsilicategermanateglassisasuitablecandidateforthe2μmlaser.Moreover,theenergytransfermechanismbetweenTm3+andHo3+ionswasinvestigated.

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简介：Thediblockcopolymersintercalatedlayeredsilicatewaspreparedviaameltdispersiontechnique.Thentheeffectofintercalatedhybridasfilleronacrylonitrile-butadiene-styreneresinwascharacterizedbyX-raydiffraction,transmissionelectronmicroscopy,stress-strainmeasurementsinelongation.

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简介：AdetailedstudyofthefluorescenceemissionpropertiesandenergytransfermechanisminEr3+/Tm3+co-dopedleadsilicateglasseswasreported.Enhancednearinfrared1.8μmandvisibleup-conversionemissionswereinvestigatedunder808and980nmexcitations,respectively.TheenergytransfermechanismbetweenEr3+andTm3+wasanalyzedaccordingtotheabsorptionspectra,theemissionspectraandthelevelstructuresofEr3+andTm3+.TheenergytransferefficiencybetweenEr3+andTm3+reached68.1%intheEr3+/Tm3+co-dopedleadsilicateglasseswhenpumpedby808nmlaserdiode.Basedontheabsorptionspectra,theJudd-Ofeltparameters,spontaneousemissionprobability,absorptionandemissioncrosssections,gaincoefficientswerecalculatedandanalyzed.Itwasfoundthatthecalculatedemissioncrosssectionandthemaximumgaincoefficientaround1.8μmwere4.9×10–21cm2and1.12cm–1,respectively.TheseresultsindicatedthattheEr3+/Tm3+co-dopedlead-silicateglasseshadpotentialapplicationinnearinfraredlasers.