简介：利用原于力显微镜研究了KTiOAsO4晶体的铁电畴，发现了这一实验方法的诸多特点。如放大倍数高，可以得到晶体表面的定量信息等，得到了KTiAsO4晶体铁电畴的原于力显微镜照片，并结合化学腐蚀光学显微法的实验结果进行了研究。最后对铁电畴的机制与消除进行了理论讨论。

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简介：采用共孔径发射和接收技术可使激光信标系统结构紧凑、控制简单。在激光的共孔径发射和接收中使用偏振耦合分光方法有分光效率高、简单可靠等优点。但是，组成地平式折轴望远镜的反射镜对s光和p光的相位延迟有差异，望远镜旋转造成的激光偏振态变化更严重地影响了偏振分光的接收效率。要保持较高的接收效率，就需要对激光相位进行动态补偿。

简介：CuFe2O4network,preparedviatheelectrostaticspraydepositiontechnique,withhighreversiblecapacityandlongcyclelifetimeforlithiumionbatteryanodematerialhasbeenreported.Thereversiblecapacitycanbefurtherenhancedbycoatinghighelectronicconductivepolypyrrole（PPy）.Atthecurrentdensityof100mA·g-1.Li/CuFe2O4electrodedeliversareversiblecapacityof842.9mAh·g-1whilethereversiblecapacityofLi/PPy-coatedCuFe2O4electrodeincreasesupto1106.7mAh-g’.Ahighcapacityof640.7mAhg"1fortheLi/PPy-coatedCuFe2O4electrodeismaintainedincontrastof398.9mAh·g-1forCuFe2O4electrodeafter60cycles,whichdemonstratesgoodelectrochemicalperformanceofthecompositeduetotheincreaseofelectronicconductivity.Theelectrochemicalimpedancespectroscopy（EIS）furtherrevealsthattheLi/PPy-coatedCuFe2O4electrodehasalowerchargetransferresistancethantheLi/CuFe2C>4electrode.

简介：Amongthemanyspecialfactorsinthespaceenvironment,spaceradiationespeciallyhighenergyheavyionradiationiswidelyregardedasoneofthecrucialfactorsthathazardthehealthandsafetyofastronaut.Itiswellknownthatbiologicaleffectsofradiationaredependentonthelinear-energy-transfer(LET)oftheemergentbeam.HeavyionshavehighLETandcouldinducecomplexandclusteredDNAdamage,whichismoredifficulttoberepairedthanindividuallesionsandisevenirreparable.

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简介：2-(二硝基亚甲基)-4，5-咪唑烷二酮(1)是1998年首次报道的一个新化合物，是Latypov等在探索合成低感高能炸药1，1-二氨基-2，2-二硝基乙烯(FOX-7)的过程中得到的一个重要中间体，它去掉羰基开环即得FOX-7，

简介：与时间依赖者本地人密度近似的框架，对簇的光反应的有效描述被用来学习Na_2和Na_4簇的the.photo吸收十字节。我们的计算结果在对实验的好同意，这被显示出。另外，我们为Na_4簇的计算光谱比GW吸收光谱在对实验的更好的同意。

简介：LargeGdCa4O(BO3)3crystalhasbeengrownbytheCzochralskimethod.ThequalityofGdCa4(BO3)3crystalwasassessedbywhite-beamsynchrotronradiationtopography.Ithasbeenfoundthatthereisasub-grainboundaryintheGdCa4O(BO3)3crystal.TheboundarydividesthelargeGdCa4O(BO3)3crystalintotwoindividuals.Duetothemisorientationbetweenthetwoindividuals,theimageshiftscanbeobservedinthesynchrotrontopopraphs.BasedonthemisorientationdeterminedbyhighresolutionX-raydiffractometer,theimageshiftswerecalculatedforseveralreflections.ThecalculationsareinagreementwiththemeasurementsfromthetopogrphsveryWell.Inaddition,theformationmechanismofsub-grainboundaryisdiscussed.2001ElsevierscienceB.V.Allrightsreserved.

简介：Rhodium-andironphosphate-basedcatalystsarebyfarthemostpromisingcatalystsforoxy-brominationofmethane(OBM)reaction.However,mostliteraturereportedeitherRh-orFePO4-basedcatalysts,andtheresultswererarelystudiedinauniformenvironmentalcondition.Inthisreport,comparativestudywasconductedonsilica-andsiliconcarbide-supportedrhodiumandironphosphatecatalystswiththemainfocusesonstabilityperformanceandcokedeposition.ThecatalyticresultsdemonstratedthatthestabilityofbothRh-andFePO4-basedcatalystswasgreatlyinfluencedbythesupportsused,andsiliconcarbide-supportedcatalystsshowedmuchbetteranti-cokingabilityascomparedwithsilica-supportedones.Temperature-programmedoxidationovertheusedcatalystsfurtherindicatedthatthecokeformationmechanismswerecompletelydifferentbetweensilica-supportedrhodiumandironphosphatecatalysts.WhilecokesmightbecausedbycondensationofCH2Br2oversupportedironphosphate,methanedecompositionmightbethereasonforcokeformationoversilica-supportedrhodiumcatalyst.ThesefindingsmightpavethewayfordesigninghighlyefficientandstablecatalystsoftheOBMreaction.

简介：利用质谱法定量分析了^6Li（n，α）T反应中伴随产生的^4He核，得到了产氚量。采用自膨胀密封方法在常温下定量制备了密封锂铅合金靶。靶件在西安脉冲堆的跑兔辐照通道内辐照了2h，冷却15d后进行测量。建立了去除氢同位素干扰的气体样品处理平台，并以含氢的模拟标准气进行了验证。研究并建立了测量。He的在线同位素稀释法，并用空气进行了验证。靶件在700℃被熔融后释放^4He，首次熔融的^4He释放率达到99．9％，产氚量测量结果的不确定度小于6％。

简介：Inordertoinvestigatethefiresuppressioneffectivenessofwatermistwithmetalchlorideadditives,ultrafinewatermistsofthesesaltswithdiametersabout10μmwereintroducedintoCH4/airnon-premixedflameinthecupburner.Resultsshowedthatthesedropletshardtomakeitselftotheflamefrontunderthecupburnerflowconditionsfunctionedasacarrierofthevaporizedsolidparticlesoritsdecomposedmaterials.Themetalchlorideimprovedfiresuppressionefficacyofwatermistwhichwereaffectedbythetypeandconcentrationofmetalchloride.Onamassbasis,thereisafiresuppressioneffectivenessrelationshipofMgCl2

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简介：CrystallineTiO2（P25）andisolatedtitanatespeciesinaZSM-5structure（TS-1）weremodifiedwithAuandAg,respectively,andtestedinthegas-phasephotocatalyticCO2reductionunderhighpurityconditions.Thenoblemetalmodificationwasperformedbyphotodeposition.LightabsorbancepropertiesofthecatalystsareexaminedwithUV–Visspectroscopybeforeandaftertheactivitytest.Inthegas-phasephotocatalyticCO2reduction,itwasobservedthatthecatalystswithAgnanostructuresaremoreactivethanthosewithAunanostructures.Itisthusfoundthattheenergeticdifferencebetweenthebandgapenergyofthesemiconductorandthepositionoftheplasmonisinfluencingthephotocatalyticactivity.Potentially,plasmonexcitationduetovisiblelightabsorptionresultsinplasmonresonanceenergy,whichaffectstheexcitationofthesemiconductorpositively.Therefore,anoverlapbetweenbandgapenergyofthesemiconductorandmetalplasmonisneeded.

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简介：Chemical-loopingcombustion(CLC)isanovelcombustiontechniquewithinherentCO2separation.Magnetite(Fe3O4)wasselectedastheoxygencarrier.Shenhuacoal(InnerMongolia,China),strawcokeandnaturalcokewereusedasfuelsforthisstudy.Influencesofoperationtemperatures,coaltoFe3O4massratios,anddifferentkindsoffuelsonthereductioncharacteristicsoftheoxygencarrierwereinvestigatedusinganatmospherethermogravimetricanalyzer(TGA).Scanningelectronmicroscopy(SEM)wasusedtoanalysethecharacteristicofthesolidresidues.Experimentalresultsshownthatthereactionbetweenthecoalandtheoxygencarrierbecomestrongatatemperatureofhigherthan800℃.Astheoperationtemperaturerises,thereductionconversionrateincreases.Atthetemperaturesof850oС,900℃,and950℃,thereductionconversionrateswere37.1%,46.5%,and54.1%respectively.However,SEMimagesshowthatatthetemperatureofhigherthan950℃,theironoxidesbecomemeltedandsintered.Thepossibleoperationtemperatureshouldbekeptaround900℃.WhenthemassratiosofcoaltoFe3O4were5/95,10/90,15/85,and20/80,thereductionconversionrateswere29.5%,40.8%,46.5%,and46.6%respectively.Withtheincreaseofcoal,theconversionrategoesup.Butthereexistanoptimalratioaround15/85.Comparisonsbasedondifferentkindsoffuelsshowthatthesolidfuelwithahighervolatileandamoredevelopedporestructureisconducivetothereductionreactivityoftheoxygencarrier.

简介：WeinvestigatethesurfacestructureandcompositionofaYBa2Cu3Oy(YCO)thinfilmodifiedbyCF4plasmafluorination.Inadditiontotheabsorptionofhydrocarbons,chemicalreactionsoftheYBCOsurfacetakeplaceduringCF4plasmatreatment.Variousx-rayphotoelectronspectroscopicdataarereportedanddiscussed.Theexistenceofathinbarrierisconfirmed,whichhomogeneouslycoverstheedgeofthebaseYBCOfilminourinterfaceengineeringJosephsonjunction.MeasurementsofAugerelectronspectroscopicdataandtheresistanceversustemperatureindicatethatthebarrierisacontrollable-insulatinglayer.

简介：Inthisstudy,nanocrystallineCo–Ni–MgferritepowderswithcompositionCo0.5Ni0.5-xMgxFe2O4aresuccessfullysynthesizedbytheco-precipitationmethod.Asystematicinvestigationonthestructural,morphologicalandmagneticpropertiesofun-dopedandMg-dopedCo–Niferritenanoparticlesiscarriedout.Thepreparedsamplesarecharacterizedusingx-raydiffraction（XRD）analysis,Fouriertransforminfraredspectroscopy（FTIR）,fieldemissionscanningelectronmicroscopy（FESEM）,andvibratingsamplemagnetometry（VSM）.TheXRDanalysesofthesynthesizedsamplesconfirmtheformationofsingle-phasecubicspinelstructureswithcrystallitesizesinarangeof32nmto36nm.ThelatticeconstantincreaseswithincreasingMgcontent.FESEMimagesshowthatthesynthesizedsamplesarehomogeneouswithauniformlydistributedgrain.TheresultsofIRspectroscopyanalysisindicatetheformationoffunctionalgroupsofspinelferriteintheco-precipitationprocess.ByincreasingMg2+substitution,roomtemperaturemagneticmeasurementshowsthatmaximummagnetizationandcoercivityincreasefrom57.35emu/gto61.49emu/gand603.26Oeto684.11Oe（1Oe=79.5775A·m-1）,respectively.ThehighervaluesofmagnetizationMsandMrsuggestthattheoptimumcompositionisCo0.5Ni0.4Mg0.1Fe2O4thatcanbeappliedtohigh-densityrecordingmediaandmicrowavedevices.

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+。