简介:Lithium-aluminum-cobalt-nickeloxideLiAlxCoyNi1xyO2particles,generallyusedascathodeoflithiumbattery,werepreparedbychemicalcoprecipitationfromanaqueoussolutionofLiOH,Al(NO3)3,Co(NO3)2andNi(NO3)2withNH4OH.XRD,SEMandFTIRwereusedtoexaminetheeffectofnickelcontentontheproduct.FTIRpatternsshowedthatincreaseinnickelcontentdecreasedtheabsorptionstrengthofthepeakofspinelstructureoftheproduct,attributedtotheoccupationbynickelinthealuminumsites.Particlesizeandelectricalpropertiesofthelithium-aluminum-cobalt-nickeloxide(abbreviatedasLACNO)particleswerealsodetermined.
简介:The(2+1)-dimensionalBKPequationintheHirotabilinearformisstudiedduringthiswork.WronskianandGrammiantechniquesareappliedtotheconstructionofWronskianandGrammiansolutionsofthisequation,respectively.ItisshownthatthesesolutionscanbeexpressedasnotonlyPfaffiansbutalsoWronskiansandGrammians.
简介:The1/3subharmonicsolutionfortheDuffing'sequationisinvestigatedbyusingthemethodsofharmonicbalanceandnumericalintegration.Thesensitivityofparametervariationforthetransientprocessandthetransientprocessfortheperturbanceinitialconditionsarestudied.Overandabove,theprecisionofnumericalintegrationmethodisdiscussedandthenumericalintegrationmethodiscomparedwiththeharmonicbalancemethod.Finally,asymptoticalstabilityofthepuresubharmonicoscillationselementisinspected.
简介:Inthispaper,ahigh-orderfinite-volumeschemeispresentedfortheone-dimensionalscalarandinviscidEulerconservationlaws.TheSimpson’squadratureruleisusedtoachievehigh-orderaccuracyintime.TogetthepointvalueoftheSimpson’squadrature,thecharacteristictheoryisusedtoobtainthepositionsofthegridpointsateachsub-timestagealongthecharacteristiccurves,andthethird-orderandfifth-ordercentralweightedessentiallynon-oscillatory(CWENO)reconstructionisadoptedtoestimatethecellpointvalues.Severalstandardone-dimensionalexamplesareusedtoverifythehigh-orderaccuracy,convergenceandcapabilityofcapturingshock.
简介:在现在的纸,包含三个任意的函数为的一个一般解决方案概括(2+1)维的KdV-mKdV方程,它被导出从概括(1+1)维的KdV-mKdV方程,首先借助于Wiess被介绍,小鼓,Carnevale(WTC)截断方法。然后有考虑的几条能量守恒定律的multisymplectic明确的表达被介绍为概括(2+1)维的KdV-mKdV方程基于桥的multisymplectic理论。随后,源于以便以Jacobi椭圆形的功能的合理功能模仿周期的波浪答案一般答案,一个半含蓄的multi-symplectic计划被构造那等价于Preissmann计划。从数字实验的结果,我们能断定multi-symplectic计划能精确地模仿周期的波浪答案概括(2+1)维的KdV-mKdV方程当时近似保存能量守恒定律。
简介:AhighlyefficientH1-Galerkinmixedfiniteelementmethod(MFEM)ispresentedwithlineartriangularelementfortheparabolicintegro-differentialequation.Firstly,somenewresultsabouttheintegralestimationandasymptoticexpansionsarestudied.Then,thesuperconvergenceoforderO(h2)forboththeoriginalvariableuinH1(π)normandthefluxp=uinH(div,π)normisderivedthroughtheinterpolationpostprocessingtechnique.Furthermore,withthehelpoftheasymptoticexpansionsandasuitableauxiliaryproblem,theextrapolationsolutionswithaccuracyO(h3)areobtainedfortheabovetwovariables.Finally,somenumericalresultsareprovidedtoconfirmvalidityofthetheoreticalanalysisandexcellentperformanceoftheproposedmethod.
简介:针对1点RANSAC(RandomSampleConsensus)单目视觉EKF(ExtendedKalmanFilter)算法中的滤波发散问题,分析了滤波发散的产生原因,提出了一种基于渐消记忆滤波的1点RANSAC单目视觉姿态估计算法。该算法通过在EKF滤波方程中引入加权因子,逐渐加大当前数据的权重,相应地减少旧数据的权重,有效地扼制了算法中的滤波发散问题。最后通过两组验证性实验验证说明了算法的有效性。实验结果表明:该算法能够有效地解决1点RANSAC单目视觉EKF算法中的滤波发散问题,具有更高的精度。第一组双轴联动实验,航向角的平均误差减小2.4158?,俯仰角平均误差减小0.1782?;第二组偏航轴大角度转动实验,摄像机航向角的估计误差一直保持在1.5?以内。
简介:Perovskite-typeLa1-xCexMnO3(x=0-10%)catalystswerepreparedbyflamespraypyrolysisandtheiractivitiesduringthecatalyticoxidationofbenzenewereexaminedoverthetemperaturerangeof100-450℃.ThestructuralpropertiesandreducibilityofthesematerialswerealsocharacterizedbyX-raydiffraction(XRD),N2adsorption/desorption,H2temperature-programmedreduction(H2-TPR)andX-rayphotoelectronspectroscopy(XPS).TheincorporationofCewasfoundtoimprovethebenzeneoxidationactivity,andtheperovskiteinwhichxwas0.1exhibitedthehighestactivity.Phasecompositionandsurfaceelementalanalysesindicatedthatnon-stoichiometriccompoundswerepresent.TheincorporationofCehadanegligibleeffectonthespecificsurfaceareaoftheperovskitesandhencethisfactorhaslittleimpactonthecatalyticactivity.IntroductionofCe44+resultedinmodificationofthechemicalstatesofbothB-siteionsandoxygenspeciesandfacilitatedthereducibilityoftheperovskite.ThesurfaceMn4+/Mn3+ratiowasincreasedasaresultofCe4+substitution,whileadecreaseinthesurface-adsorbedO/latticeO(Oads/Olatt)ratiowasobserved.Therelationshipbetweenthesurfaceelementalratiosandcatalyticactivitywasestablishedtoallowabetterunderstandingoftheprocessbywhichbenzeneisoxidizedoverperovskites.
简介:阴极材料李[CoxNiyMn1?x?y]为锂的O2第二等的电池被一条新线路作为一位先锋用分层的双氢氧化物(LDH)准备了。结果有-NaFeO2结构的分层的阶段在菱形的系统结晶,与有到0.47nm的夹层间距结束的空格组R-3m。X光检查光电子光谱学(XPS)被用来测量公司,Ni和Mn的氧化状态。在结构和李的电气化学的性质上改变Co/Ni/Mn比率的效果[CoxNiyMn1?x?y]O2被X光检查衍射和电气化学的测试调查了。产品表明了相当稳定的骑车行为,与为有Co/Ni/Mn=1/1/1的分层的材料的118mAh/g的一个可逆能力。
简介:为了填补船测海深数据空白,给出了海底地形起伏与重力异常和重力异常垂直梯度之间的导纳函数关系。据此,以测高重力异常、重力异常垂直梯度作为输入数据,采用线性回归分析技术,在西南太平洋相关海域开展了海底地形反演试验。结果表明,通过不同方法获取的比例因子与海底地形呈现一定的内在联系,地形平坦海域,比例因子较小;海山分布较多的地形起伏较大的海域,比例因子相对较大,反映了重力数据与海底地形较强的相关性。同时,采用线性回归方法构建的海底地形模型检核精度最高,相较于传统方法获取的海底地形模型,精度最高提升了46%左右,与ETOPO1海深模型和DTU10海深模型相比较,模型精度最大提高了近一倍有余。另外,不同方法对于不同的海底地形具有各自不同的优势,靠近海山区域,采用线性回归技术反演的海深结果优于传统方法;在海山部分,传统方法反演精度又好于线性回归技术。不同数据源反演海底地形的统计结果表明,以重力异常垂直梯度构建的海底地形模型的检核精度优于以重力异常作为输入数据构建的海底地形模型。
简介:为了实现侵彻弹药的高效毁伤,硬目标侵彻引信必须完成最佳炸点识别和起爆控制任务。对比研究了两类炸点精确控制方案:一类是基于侵彻深度经验公式,另一类是基于侵彻引信记录装置中的高g值加速度计测量信息。前者的精度完全依赖于先验信息,而后者的精度则取决于冲击加速度的精确测量和控制算法的实时解算。给出了基于伪自相关的空穴识别算法。冲击加速度信号自乘实现调频脉冲压缩,再通过低通滤波即可提取出平滑的侵彻信号包络线。进一步,详细推导了实时计算侵彻深度的积分算法。利用数学仿真的侵彻两层钢靶和实测的侵彻五层混凝土靶冲击加速度进行了算法验证。空穴识别算法能够准确识别出侵彻介质的层数,而冲击加速度的双积分与弹体实际位移保持一致,相对误差约3%。