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简介：Small-angleX-rayscattering(SAXS)usingsynchrotronradiationasX-raysourcehasbeenemployedtocharactcizcthemicroscopicstructrureoforgano-modifiedmesoporousmolecularsieves(organo-MSU-X)preparedbyaone-pottemplate-directedsynthesis.ItisshownthattheSAXSprofileishardlyconstantwithPorod’slawshowinganegativeslope,i.e.,negativedeviation.Thissuggeststhatthereisdiffuseinterfaciallayerlocatedbetweentheporesandthematrix.Thissuggeststhattheorganicgroupsremaincovalentlylinkedtothematrix,asindicatedby^29SiCPMASNMRandFT-IR.Theaveragethicknessoftheinterfaciallayerwasfoundtobeabout1nmforeachofthethreesampleswithdifferentkindsandthesameamounts(20?oforganicgroups.Thiskindofmaterialhasalsobeenprovedtopossessbothsurfaceandmassfractalstructureoftheamophousporoussilicamaterials.2001ElsevierScienceB.V.Allrightsreserved.

简介：Inthiswork,negativedielectricnematicliquidcrystalSLC12V620-400,chiraldopantS811,andlaserdyeDCMareusedtopreparedye-dopedchiralnematicliquidcrystallasersample.Inordertoinvestigatetemperature-tunablelasinginnegativedielectricchiralnematicliquidcrystal,wemeasurethetransmissionandlasingspectrumofthissample.Thephotonicbandgap(PBG)isobservedtoredshiftwithitswidthreducingfrom71.2nmto40.2nm,anditsshort-wavelengthbandedgemoves55.3nmwhilethelong-wavelengthbandedgeonlymoves24.9nm.Thewavelengthofoutputlaserisfoundtoredshiftfrom614.4nmat20°Cto662.8nmat67°C,whichisverydifferentfromthepreviousexperimentalphenomena.Therefractiveindices,parallelandperpendiculartothedirectorinchiralnematicliquidcrystalhavedifferentdependenciesontemperature.Theexperimentshowsthatthepitchofthischiralnematicliquidcrystalincreaseswiththeincreaseoftemperature.ThedecreaseinthePBGwidth,differentshiftsofbandedges,andtheredshiftoflaserwavelengtharetheresultsofrefractiveindiceschangeandpitchthermalelongation.

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简介：NanoporousanataseTiO2(np-TiO2)electrodeshavebeendevelopedviatheanodizationoftitaniumfoilsinfluoridecontainingelectrolytes,anditsapplicationinrechargeablelithium-ionbatteries(LIBs)wasinvestigated.Fourdifferenttypesofnp-TiO2electrodeswithdifferentporediametersof14.7±8.2nm,12.8±6.8nm,11.0±5.5,and26.7±13.6nmwerefabricatedforevaluatingtheeffectofnanoporouscharacteristicsontheLIBperformance.Thedischargecapacityofthefourbatterytypes1,2,3,and4were132.7mAhg-1,316.7mAhg-1,154.3mAhg-1,and228.4mAhg-1,respectively.Inaddition,theseelectrodes1,2,3,and4exhibitedreversiblecapacityof106.9mAhg-1after295th,180.9mAhg-1after220th,126.1mAhg-1after150th,and206.7mAhg-1after85thcycleatarateof1C,respectively.Itwasnotedthatthecycliclifeofthebatterieshadaninverserelationship,andthecapacityhadaproportionalrelationshiptotheporediameter.Theenhancedelectrochemicalperformanceofthenanoporouselectrodescanbeattributedtotheimprovedconductivityandtheenhancedkineticsoflithiuminsertion/extractionatelectrode/electrolyteinterfacesbecauseofthelargespecificsurfaceareaofnp-TiO2electrodes.

简介：Chiral导致异例的否定磁致电阻(NMR)广泛地在拓扑的半金属为Weyl费米子的存在被用作批评运输证据。在这微型评论，我们在非中心对称的NbP和NbAs讨论NMR现象的一般观察。我们证明NMR能从Weyl费米子或外来的效果的内在的chiral异例产生，例如霍尔信号的重迭；地依赖者在体积的不同类的当前的流动，即，当前的jetting；并且共存的小搬运人的弱本地化(WL)。控制WL的NMR重重地依赖于样品质量并且被一条显著转线路描绘从对在提高的温度的否定先生生长积极，源于在阶段连贯时间和体积的纺纱轨道的散布常数之间的比赛小衣袋。因此，没有赞美技术的支持，在NMR之间的关联和chiral异例需要被细看。因为上升旋转退化，Weyl费米子的旋转取向与动量平行或反平行，它是作为helicity知道的一个唯一的物理性质。helicity的保存为Weyl费米子的运输提供强壮的保护，它能被磁性的杂质有效地仅仅散布。与磁性、无磁性的杂质的化学的做因此是比为检测Weyl费米子的存在的NMR方法更有说服力的。

简介：Magneticlocalizedsurfaceplasmonmodesaresupportedonmetallicspiralstructures.Couplingmechanismsforthesemetamaterialresonators,whicharethejointactionofmagneticandelectriccoupling,arestudied.Basedonthestrongcoupling,spoofmagneticplasmonmodespropagatinginthebackwarddirectionareproposedalongachainofsubwavelengthresonators.Thetheoreticalanalysis,numericalsimulations,andexperimentsareingoodagreement.Theproposednovelrouteforachievingnegative-indexwaveguidinghaspotentialapplicationsinintegrateddevicesandcircuits.

简介：Thetargetofthelargenegativeionsourcebasedonneutralbeaminjection(N-NBI)istoproduceneutralbeamcurrentof22Aandbeampowerof10MWat500keVwithdurationtimeof10s.Sinceitwassuccessfullyoperatedin1996,the5.3MWneutralbeampowerat380keVwithdurationtimeof3shasbeenachieved.Inrecentyearsimprovingandenhancingthebeampoweraregoingon.Severalreasonssuchasplasmanon-uniformity,higherbeamdensityattheupperregioninthebeamprofile,

简介：Here,wereportthesynthesisofhardcarbonmaterials(RH)madefromnaturalricehuskthroughasinglepyrolysisprocessandtheirapplicationasananodeinsodium-ionbatteries.ThestudiesshowthattheelectrochemicalpropertiesofRHsareaffectedbythetreatmenttemperatures,whichdeterminethematerialsmorphology,inparticular,theirdegreeofgraphitizationandextentofcontinuouschannels(nanovoids).Thelatterareaccessibletosodiumionsandsignificantlycontributetochargestoragecapacityoftheproducedanodes.TheRHsobtainedat1600°Cdeliverthehighestreversiblecapacityof276mAhg-1mainlyduetoinsertionofsodiumionsintothenanovoids.Thisworkdeepensthebasicunderstandingoftheinfluenceofthecarbonizationtemperatureonthesodiumstoragemechanism.