简介：AnFEanalysisprocedurewaspresentedtopredictthebehaviorofsoilogeogridinterctionunderautomobileloading.Thedynamicinteractionsbetweenthetransversebars,thelongitudinalribsandthesoilweresimulatedbyasystemconsistingofnonlinearsprings,dashpotsandmasses,tostudythedeformationpropertiesofthereinforcedsoil.Theequivalentstiffnessanddampingratioscouldbedeterminedwiththeshakingtable.Thedynamicresponsesofareinforcedsubgradewereanalyzedwiththe3Dfiniteelementapproach.Thisapproachisprogrammedandappliedtoanalyzethesoilogeogridinteractionunderdynamicloading.Thecomparativeanalysisoftheresponseofthereinforcedsubgradeandthatofthesubgradewithoutreinforcementshowsthatthegeogridplacedatthebottomofthebaselayermayeffectivelyreducetheaccumulativeplasticdeformationduetothecyclicautomobileloading.

简介：Uniformlysizedα-Fe2O3hexagonalplateletsweresynthesizedbyahydrothermalprocessusingFe(OH)3suspensionandlargeamountofNaOH.ThereactionproductswerecharacterizedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM),selectedareaelectrondiffraction(SAED),andavibratingsamplemagnetometer(VSM).Theresultsshowthatthehexagonalplateletsarefine,monodisperseandconsistingofsingle-crystals.Themagnetichysteresis(M-H)curveofthesamplesmeasuredatroomtemperatureindicatesthattheα-Fe2O3micro-plateletsexhibitferromagneticbehaviorswithrelativelylowcoercivity.

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简介：有从30～80nm的尺寸的Fe3O4nanoparticles被湿milling铁粉末在一家行星的球工厂综合。阶段作文和同样综合的产品的形态学被X光检查衍射(XRD)测量，扫描电子显微镜学(SEM)和传播电子显微镜学(TEM)。NanosizedFe3O4粒子被湿milling准备金属性的铁粉末(?200网孔，99%)在与不锈钢装备的一家行星的球工厂，使用的小瓶与50:1并且以300rpm的旋转速度的ball-to-powder团比率在提取的水下面熨球。在这个方法的铁球的使用在Fe3O4formation起了一个关键作用。现在的技术简单，这个过程是容易的执行。

简介：Multi-walledcarbonnanotubes(MWNTs)with20nmouterdiameterwerepreparedbychemicalvapordepositionofethyleneusingultrafinesurface-modifiedacicularα-Fecatalystparticles.ThegrowthmechanismofMWNTsonthelargercatalystparticlesareattributedtotheinteractionbetweentheFenanoparticleswiththesurface-modifiedsilicalayer.Thisinteraction-mediatedgrowthmechanismisillustratedbystudyingtheelectronic,atomicandcrystalpropertiesofsurface-modifiedcatalystsandMWNTsproductsbycharacterizationwithX-raydiffraction(XRD),transmissionelectronmicroscopy(TEM),highresolutiontransmissionelectronmicroscopy(HRTEM),thermalgravimetricanalysis(TGA)andRamanspectra.

简介：Carbonnanotube（CNTs）/Fe-Ni/TiO2nanocompositephotocatalystshavebeensynthesizedbyaninsitufluidizedbedchemicalvapordeposition（FBCVD）method.ThecompositephotocatalystswerecharacterizedbyXRD,Ramanspectroscopy,BET,FESEM,TEM,UV-visspectroscopy,andXPS.TheresultsshowedthattheCNTsweregrowninsituonthesurfaceofTiO2.Fe（lll）inTiO2showednochemicalchangesinthegrowthofCNTs.Ni（Ⅱ）waspartlyreducedtometalNiintheFBCVDprocess,andthemetalNiactedasacatalystforthegrowthofCNTs.ThephotocatalyticactivitiesofCNTs/Fe-Ni/TiO2decreasedwiththeriseoftheFBCVDreactiontemperature.ForthesamplesynthesizedatlowFBCVDtemperature（500℃）,morethan90%andnearly50%ofmethylenebluewereremovedunderUVirradiationin180minandundervisiblelightirradiationin300min,respectively.TheprobablemechanismofsynergisticenhancementofphotocatalysisontheCNTs/Fe-Ni/TiO2nanocompositeisproposed.

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简介：针对传统天文导航方法和GNSS导航方法应用于中高轨道航天器尤其是大椭圆轨道机动航天器自主导航的缺陷，提出一种基于低轨道天基平台实时跟踪观测的轨道机动航天器在轨绝对导航方法。其具体实施过程为布置于低轨道的天基平台利用其自带观测敏感器对轨道机动航天器进行全程实时跟踪测量，并将测量所得的星光角距信息和测距信息发送至轨道机动航天器，航天器根据接收得的量测信息结合自身状态预估信息通过最优滤波估计算法实现导航解算。仿真结果表明该方案具备较强的可行性，且该导航系统具有较高的导航估计精度，能够弥补传统天文导航和GNSS导航方法的不足之处，当天基平台自主定轨精度为80m时轨道机动航天器导航位置估计误差在120m以内。

简介：针对甲酸乙酯(H(CO)OCH2CH3)与羟基自由基(OH)的反应动力学展开了理论与实验研究.在理论方面,首先通过量化计算得到了在M06-2x/ma-TZVP水平下准确的反应势能面,随后利用多结构-扭转(multi-stucturetorsionMS-T)方法对转动非谐效应进行了研究,获得了非谐校正系数,最后基于传统过渡态理论并考虑Eckart隧穿效应获得了200~2000K温度范围的反应速率常数.在实验方面,开展了激波管实验来测定H(CO)OCH2CH3与OH的反应速率常数,基于激光吸收光谱技术探测OH自由基306.7nm的吸收线,并对反射激波后高温反应过程的OH浓度变化进行测量,从而获得了900~1321K温度范围的反应速率常数,并论证了理论计算结果的合理性与准确性.