简介：TherelationshipofelectricalpropertiesofMn-dopedBa0.92Ca0.08TiO3PTCR(positivetemperaturecoefficientresistance)ceramicswithtwosinteringscheduleswasdiscussed.UsingTEM(transmissionelectronmicroscope)combinedwithEDS(energydispersiveX-rayspectrometer),theMnionsdistributedatgrainboundarieswereanalyzed.TheresultsshowthatthePTCReffectofMn-dopedPTCRceramicsismoredependentonthesinteringschedulethanthoseofMnfree.ThephenomenonmaybecausedbythevalencestatesvarianceofMnionssegregatedatthegrainboundaries.

简介：采用水热法合成了一个新的分子式为[Pb（phen）2（NO3）]·NO3的金属-有机配合物（phen=1,10-邻啡啰啉）,并对其进行了元素分析、红外光谱表征和X射线单晶衍射的结构解析.该配合物（C24H16N6O6Pb）属于单斜晶系,空间群为P21/n,晶体学数据：a=16.7035（12）,b=7.7341（5）,c=18.1198（13）,β=98.1860（10）,V=2317.0（3）3,Mr=691.62,Dc=1.983g/cm3,μ（MoKα）=7.337mm-1,F（000）=1328,Z=4.直接法解析原子位置的结果显示：R=0.0269,wR=0.0533.该配合物具有零维网状结构.

简介：对用分光光度法测定亚铁还原NH4NO3-H2SO4混合液中NO3-的方法进行了讨论,旨在建立一个测定NH4NO3-H2SO4混合液中NO-3的快速方法,运用于生产工艺的控制分析.

简介：Anewμ3-Otriiron（Ⅲ）complex[Fe3O（OBz）6（CH3OH）3]（NO3）（CH3OH）2（HOBZ=benzoicacid）hasbeensynthesized,itsstructurehasbeendeterminedandvariabletemperaturemagneticsusceptilityhasalsobeenmeasured.Inthemolecule,threeironatomsformedanequilateraltrianglewithu3-Oincenter.ThefittingtothemagneticsusceptibilityshowedthatanintramolecularantiferromagneticexchangeinteractionoccurredbetweenironatomswithJ=-25.51cm-1,andaweakerintermolecularantiferromagneticexchangeinteractionoccurredwithzJ’=-2.30cm-1.

简介：Thesinglecrystalofthecomplex[Sc（NO3）3（H2O）2]·（15C5）hasbeenpreparedinacetonitrile.Thenewcomplexhasbeencharacterizedbyelementalanalysis,IRspectra,solubilityandmolarconductancemeasurements.ThestructureofthecomplexisdeterminedbysinglecrystalX-raydiffractionanalysis.

简介：ThecrystalstructureofDi-nitratobis（ethylcaprolactam）uranyl（Ⅱ）UO2[CH2（CH2）4CONC2H5]2（NO3）2wasestablishedbyasingle-crystalX-raydiffractionstudy.Itistriclinie,spacegroupP1,witha=7.171（2）,b=8.655（3）,c=10.182（5）A,α=78.27（3）,β=70.63（3）,γ=81.76（3）°,V=581.7（4）A3,Z=l,Dc=1.94g.cm-3.FinalRvalueis0.0218.Theresultrevealsthaturanylioniscoordinatedtosixoxygenatoms,twoofthemarefromtwocarbonylgroupsofethylcaprolactamandtheotherfourarefromtwonitrategroups.

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：Kineticsofchloride/sulfate,chloride/nitrateandnitrate/sulfateforwardexchangesandreverseexchangesatsolutionconcentrationsof1N,0.2Nand0.02Non201×7strongbaseanionexchangeresin,respectively,havebeenexaminedat25℃.Itisfoundthattheforwardandthereverseexchangeratesofthetwogivenionsatlowsolutionconcentration,respectively,underidenticalconditionscanbecontrolledbydifferentmechanisms,whilethoseathighsolutionconcentrationareallcontrolledbyparticlediffusion.Theternaryexchangeratesofsulfate/(chloride+nitrate)andnitrate/(chloride+sulfate)havealsobeenexamined.

简介：本文通过高分辨X射线衍射及掠入射(GID)的实验方法对生长在SrTiO3衬底上的LLa2/3Ca1/3MnO3和YBaCu3O7单层膜及YBa2Cu3O7-x/La2／3Ca1／3MnO3异质结构双层薄膜的微结构进行了研究。结果发现，所有薄膜都呈c向生长。由于热膨胀系数的不同而引起的热应力使得LCMO膜的晶格参数与靶材的相差较大。La2/3Ca1/3MnO3在单层腹及双层膜中都由靶材的立方结构变成了薄膜状态的四方结构。YBa2Cu3O7在单层膜及双层膜中都由靶材的正交结构变成了薄膜状态的四方结构。La2/3Ca1/3MnO3膜与YBa2Cu3O7膜在不同的样品中处于不同的应力状态。

简介：Eu2+andDy3+codoped(Ca,Sr)7(SiO3)6Cl2yellowphosphorsweresuccessfullysynthesizedbyself-fluxmethod.Thestructure,morphologyandphotoluminescencepropertieswereinvestigatedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM)andphotoluminescencespectra.Theas-preparedphosphorshowedabroademissionspectrumcenteredat550nmforEu2+single-dopedphosphor,whilelocatedat548–544nmfortheEu2+,Dy3+codopedsamplesunderexcitationat380nmlight.TheemissionintensitywasgreatlyimprovedwhenDy3+wasdopedintothe(Ca,Sr)7(SiO3)6Cl2:Eu2+system.Thecomposition-optimizedsamplewith3mol.%ofDy3+andconstant10mol.%ofEu2+exhibiteda220%PLenhancementcomparedtothephosphorwith10mol.%Eu2+single-doped.Meanwhile,itwasfoundthatthequantumefficiencyofphosphornamely(Ca,Sr)7(SiO3)6Cl2:3mol.%Dy3+,10mol.%Eu2+couldgetupto24.6%.Thesynthesizedyellow-emitting(Ca,Sr)7(SiO3)6Cl2:Dy3+,Eu2+isapromisingcandidateashigh-efficiencyyellowphosphorforNUV-excitedwhiteLEDs.

简介：(1-x)La_(0.67)Ca_(0.33)MnO_3/Cr_2O_3(LCMO)+xCr_2O_3composites被一个新液相方法综合。XRD和SEM大小表明在LCMO结构和LCMO的晶格常数可溶的很少Cr_2O_3几乎没变化，当大多数Cr_2O_3在谷物边界或在LCMO谷物的表面上是分布式的时。Inresistivity对温度大小，金属--绝缘体转变被观察什么时候x<0.20。抵抗力增加和金属--绝缘体转变温度与Cr_2O_3的增加的内容减少。一个随机的电阻器网络(KRN)模型被使用，到模仿混合样品的运输性质。模拟结果同意试验性的观察。结果证明方法为理解maganite的composites的电子运输是合理的。

简介：为了满足工艺生产的需要，经过多次试验论证，对循环水中NO3^-含量的分析方法进行了改进，为判断循环水漏氨提供了有力的保障。

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：

简介：Duetotheremarkablemagnetoresistance(MR)effectonperovskite-typemanganite,magnetoelectronicsandspintronicshavebecomeattractivesubjectsofexperimentalandtheoreticalinvestigationsfortheapplicationpurpose.(La0.9Nd0.1)2/3Ca1/3Mn1-xFexO3(x=0,x=0.05)werepreparedsuccessfullybysol-gelmethod.Thestructure,magneticproperties,andtransportpropertiesofthecompoundswereinvestigated.Themagnetoresistanceeffectdependsonthecompositionandthetemperature.XRDpatternsshowthatthecompoundisasinglephasepolycrystalwithpseudocubicstructure.Alargenegativeisotropicmagnetoresistanceeffectinthesampleswereobservedatlowtemperatureregion.ThemaximumMRofthesampleswas77%and97%,respectively.Itwasmostlikelyduetothescatteringorthetunnelingtransportofspin-polarizedcarriersinlatticeunderstrongmagneticfield.

简介：FieldlysimetermethodwasemployedtoinvestigatethedownwardmovementandleachingofNappliedtosummercorn(ZeamayL.)ondrylandsoilinBeijing,AN-fertilizer(120kgNhm^-2)andacontroltreatmentwerarrangedforthestudy.Soilsolutionwascollectedatdepthsof20,40,60,120and170cm,whileleachtewasollectedatthebottom(220cm)ofthelysimeter,TheresultsshowedthatthedownwardmovementofNO3^-Ninsoilprofilewasgreatlyaffectedbyrainfallpattern.ThepeakofleachedNO3^-Nfrombothtreatmentscoincidedwiththepeakoftherainfall.Inaddition,leachedNO3^-Nfrombothtreatmentsandrainfallweresignificantlycorrelated(P<0.05).TheamountofleachedNO3^-NwasnotgreatintheN-fertilizertreatment,TheresultsalsosuggestedthatNfertilizationcouldcauseNO3^--Ncontaminationofgroundeaterduringtherainyseason.

简介：ThetransportpropertiesintheLa2/3(Ca1-xSrx)1/3MnO3(x=0,1/3,2/3)filmspreparedusingtheRFmagnetronsputteringmethodwereinvestigated.TheeffectoftheCa,Srdouble-dopingattheApositionintheLa2/3A1/3MnO3onthestructureofthetargetsandtransportofthefilmshasbeenstudied.Withtheincreaseofx,thestructuresofthetargetstransformfromtherhombohedralphasetothecubicphase;themetal-insulatorphasetransitiontemperature(Tp)ofthefilmsincreases;andthecorrespondingpeakresistivitydecreases.Allthephenomenacanbequalitativelyexplainedbythelatticeeffect.

简介：BACKGROUND:Previousstudieshaveshownthatthemitochondrialstructureandfunctionaredamagedinanimalmodelsofepilepsy.Inaddition,theBcl-2proteiniscapableofregulatingmitochondrialstability.OBJECTIVE:ToobserveandvalidatechangesinmitochondrialstructureandBcl-2expression,andtoanalyzethesecharacteristicsinthehippocampalCA3regionofratmodelsofepilepsy.DESIGN,TIMEANDSETTING:Thisrandomized,controlled,animalexperimentwasperformedattheLaboratoryofElectronMicroscopyandDepartmentofHistologyandEmbryology,LuzhouMedicalCollegebetween2007and2008.MATERIALS:CoriamyrtinwasprovidedbythePharmacyFactoryofWestChinaUniversityofMedicalSciences.TheprimaryandsecondaryantibodieswereprovidedbyZhongshanGoldenbridgeBiotechnology,Beijing.METHODS:Atotalof44adult,male,SpragueDawleyratswererandomlydividedintocontrol(n=11)andepilepsy(n=33)groups.Ratsintheepilepsygroupwereinducedbycoriamyrtin(50μg/kg),whichwasinjectedintothelateralventricles.Theratswerethenobservedat3,6,and24hoursafterepilepsyinduction,with11ratsateachtimepoint.Epilepsywasnotinducedinratsfromthecontrolgroup.MAINOUTCOMEMEASURES:PathologicalchangesinthehippocampalCA3regionwereobservedbylightmicroscopy;Bcl-2expressionwasanalyzedbyimmunohistochemistry;andmitochondrialchangesinthehippocampuswereobservedundertransmissionelectronmicroscopy.RESULTS:(1)ThecontrolgroupdisplayedverylittleBcl-2proteinexpressioninthehippocampalCA3region.However,after3hoursofepilepsy,expressionwasvisible.By6hours,expressionpeakedandthensubsequentlydecreasedafter24hours,butremainedhigherthanthecontrolgroup(P<0.05).(2)Mitochondriaweredamagedtovaryingdegreesintheepilepsygroups.Forexample,mitochondriaedema,cristaespaceincrease,anddisappearanceofmitochondriawereapparent.Moreover,mitochondrialdamageoccurredpriortopathologicalchangesintheneuronsandnucleolus.CONCLUSION:

简介：Ca_3Co_2O_6，Na和Ni的电子结构做了模型被被基于的Camhride连续全部的精力包裹(CASTEP)的量化学药品软件学习，在密度函数理论(DFT)和伪潜力上。优点(Z)的电子传导性，seebeckcoefficient，热传导性和图被计算。精力乐队结构在做semiconductors.Na的模型shoivs由于代理杂质揭示杂质层次的形式p类型半导体的特性，而是做Ni的模型是n-typesemiconductor。计算结果证明做的模型的电的传导性比的高非--做的模型，当Seebeck系数和做的模型的热电导率是比非做的那些低的时。因为大增加，电的电导率，做Na的模型的Z被提高，热电的性质被改进。作为Seebeck系数的大衰落，在另一方面，Ni-的Z做了模型不到的非--做的模型。

简介：InsituhighpressureenergydispersiveX-raydiffractionmeasurementsonlayeredperovskite-likemanganateCa3Mn2O7underpressuresupto35GPahavebeenPerformedbyusingdiamondanvilcellwithsynchrotronradiation.Theresultsshowthatthestructureoflayeredperovskite-likemanganateCa3Mn2O7isunstableunderpressureduetotheeasycompressionofNaCl-typeblocks.ThestructureofCa3Mn2O7underwenttwophasetransitionsunderpressuresintherangeof0-35GPa.Onewasatabout1.3GPawiththecrystalstructurechangingfromtetragonaltgoorthorhombic.Theotherwasatabout9.5GPawiththecrystalstructurechangingformorthorhombicbacktoanothertetragonal.