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简介：Synchronousgammaoscillationsarebelievedtoplayaprominentroleintheinformationprocessingofbiologicalneuralsystems.Experimentalobservationshavefoundthatthefrequencyandpowerofgammaoscillationsintheprimaryvisualcortex(V1zone)areregulatedbytheilluminationcontrastofvisualstimulus.However,theunderlyingmechanismofhowthesynchronousoscillationsdependontheilluminationcontrasthasnotbeenwellexplained.Weproposealocalexcitatory/inhibitory(E/I)neuronalnetworkofintegrate-and-fire(IAF)neuronswiththedifference-of-Gaussians(DOG)receptivefieldtounveilthismechanism.Simulationresultsdemonstratethatthehighertheilluminationcontrast,thehigherthefrequencyofgammaoscillations.Thepowerofgammaoscillationsalsoincreaseswiththeincreaseofilluminationcontrast.Theseresultsareconsistentwiththeexperimentalfindings.

简介：W，N共同做TiO2nanoparticles被一个solgel方法综合。准备样品被X光检查衍射(XRD)描绘，域排放扫描电子显微镜学(FE-SEM)，传播电子显微镜学(TEM)，Fourier变换红外线的光谱学(英尺红外)，X光检查光电子光谱学(XPS)和弥漫的反射spectrophotometry(医生)。结果证明共同做的光催化剂是有22.5nm的最小的粒子尺寸的实质上一致的球形的粒子。比作未做的TiO2，N-TiO2和P-25，W的吸收边，N共同做转移到更长的波长的TiO2和它为在Xe灯(350W)下面的甲基橘子(瞬间)的降级的photocatalytic活动更高。

简介：NanofluidswerepreparedbydispersingCunanoparticles(~20nm)inn-tetradecanebyatwo-stepmethod.Theeffectivethermalconductivitywasmeasuredforvariousnanoparticlevolumefractions(0.0001-0.02)andtemperatures(306.22-452.66K).TheexperimentaldatacompareswellwiththeJangandChoimodel.Thethermalconductivityenhancementwaslowerabove391.06Kthanforthatbetween306.22and360.77K.Theinterfacialthermalresistanceincreasedwithincreasingtemperature.Theeffectivethermalconductivityenhancementwasgreaterthanthatobtainedwithamoreviscousfluidasthebasemediaat452.66KbecauseofnanoconvectioninducedbynanoparticleBrownianmotionathightemperature.

简介：DrivenbycuriosityaboutpossibleflightoptionsfortheChang’e-2spacecraftafteritremainsattheSun-EarthL2point,effectiveapproachesweredevelopedfordesigningpreliminaryfuel-optimalnear-Earthasteroidflybytrajectories.Theapproachesincludetheuseofmodifiedunstablemanifolds,gridsearchofthemanifolds’parameters,andatwo-impulsemaneuverfororbitalphasematchingandz-axisbiaschange,andaredemonstratedtobeeffectiveinasteroidtargetscreeningandtrajectoryoptimization.Asteroidflybysareexpectedtobewithinadistanceof2×107kmfromtheEarthowingtotheconstrainedEarth-spacecraftcommunicationrange.Inthiscase,thespacecraft’sorbitalmotionissignificantlyaffectedbythegravitiesofboththeSunandtheEarth,andtherefore,theconceptofthe"heliocentricoscillating-Keplerorbit"isproposed,becausetheclassicalorbitalelementsoftheflybytrajectoriesreferencedintheheliocentricinertialframeoscillatesignificantlywithrespecttotime.Theanalysisandresultspresentedinthisstudyshowthat,amongtheasteroidswhoseorbitsarethemostaccuratelypredicted,"Toutatis","2005NZ6",or"2010CL19"mightbeencounteredbyChang’e-2inlate2012or2013withtotalimpulseslessthan100m/s.