简介：AsimplespectrophotometricassayofH2O2andglucoseusingAgnanoparticleshasbeencarriedout.RelyingonthesynergisticeffectofH2O2reductionandultraviolet(UV)irradiation,Agnanoparticleswithenhancedabsorptionsignalsweresynthesized.H2O2servedasareducingagentintheAgnanoparticlesformationinwhichAg+wasreducedtoAg0byO2àgeneratedviathedecompositionofH2O2inalkalinemedia.Ontheotherhand,photoreductionofAg+toAg0underUVirradiationsalsocontributedtothenanoparticlesformation.ThesynthesizednanoparticleswerecharacterizedbyTEM,XPS,andXRD.TheproposedmethodcoulddetermineH2O2withconcentrationsrangingfrom5.010à7to6.010à5mol/L.Thedetectionlimitwasestimatedtobe2.010à7mol/L.SincetheconversionofglucosetogluconicacidcatalyzedbyglucoseoxidasewascompaniedwiththeformationofH2O2,thesensingprotocolhasbeensuccessfullyutilizedforthedeterminationofglucoseinhumanbloodsamples.Theresultswereingoodagreementwiththosedeterminedbyalocalhospital.Thiscolorimetricsensorthusholdsgreatpromisesinclinicalapplications.

简介：用离子交换法将具有Keggin结构TBA4H3PW7Mo3Cu2O38（H2O）2（M=Fe2＋，Co2＋，Cu2＋，Ni2＋和Mn2＋）嵌入到Zn2A1黏土中，得到层状化合物LDH-PW7Mo3Cu2O38（H2O）2（M=Fe2＋，Co2＋，Cu2＋，Ni2＋和Mn2＋），并用XRD，IR，uV对其进行了表征．结果表明：杂多阴离子进入黏土后，仍保留了其Keggin结构．利用合成的层状化合物为催化剂，以顺丁烯二酸与HzO。的环氧化反应为模型反应考察其催化活性，结果表明：层状化合物在环氧化反应中显示优良的催化性能．

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简介：TiO2@ZrO2@Y2O3:有coremultishell结构的Eu3+合成粒子通过layer-by-layer(LBL)的联合被综合自己组装方法和一个solgel过程。获得的样品与扫描电子被描绘显微镜学(SEM)，传播电子显微镜学(TEM)，X光检查光电子光谱学(XPS)，X光检查衍射(XRD)，和荧光spectrophotometry。结果证明合成粒子有coremultishell结构，球形的形态学，和狭窄的尺寸分布。TiO2核心上的ZrO2层的存在能有效地阻止在TiO2核心和Y2O3壳之间的反应；为在在TiO2@ZrO2@Y2O3的TiO2核心和Y2O3壳之间的反应的温度:Eucoremultishell黄磷能被300提高

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简介：Ahighlyeffcientandgeneralmethodforthesynthesisofpolyfunctionalized4H-pyransisestablishedthroughaone-potmulticomponentcyclocondensationofaromaticaldehydeswithCHacids,malononitrileandethylacetoacetateusingnanosilicasupportedtin(II)chlorideasacatalyst.InthismethodSnCl2/nanoSiO2wasusedasgreenandreusablecatalyst.Excellentyields,shortreactiontimes,simpleworkup,andinexpensivenessandcommerciallyavailabilityofthecatalystaretheadvantagesofthismethod.

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简介：ThecorrelationbetweenphasestructuresandsurfaceacidityofAl2O3supportscalcinedatdifferenttemperaturesandthecatalyticperformanceofNi/Al2O3catalystsintheproductionofsyntheticnaturalgas(SNG)viaCOmethanationwassystematicallyinvestigated.Aseriesof10wt%NiO/Al2O3catalystswerepreparedbytheconventionalimpregnationmethod,andthephasestructuresandsurfaceacidityofAl2O3supportswereadjustedbycalciningthecommercialγ-Al2O3atdifferenttemperatures(600–1200C).COmethanationreactionwascarriedoutinthetemperaturerangeof300–600Catdifferentweighthourlyspacevelocities(WHSV=30000and120000mL·g-1h-1)andpressures(0.1and3.0MPa).ItwasfoundthathighcalcinationtemperaturenotonlyledtothegrowthinNiparticlesize,butalsoweakenedtheinteractionbetweenNinanoparticlesandAl2O3supportsduetotherapiddecreaseofthespecificsurfaceareaandacidityofAl2O3supports.Interestingly,NicatalystssupportedonAl2O3calcinedat1200C(Ni/Al2O3-1200)exhibitedthebestcatalyticactivityforCOmethanationunderdifferentreactionconditions.LifetimereactiontestsalsoindicatedthatNi/Al2O3-1200wasthemostactiveandstablecatalystcomparedwiththeotherthreecatalysts,whosesupportswerecalcinedatlowertemperatures(600,800and1000C).ThesefindingswouldthereforebehelpfultodevelopNi/Al2O3methanationcatalystforSNGproduction.

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简介：作者主要学习追踪算法到稳定的Euler系统和等温的Euler系统的波浪前面产生的弱答案的差别。在起始的数据足够地具有的假设下面小全部的变化，稳定的Euler系统和等温的超声的流动的系统的解决方案之间的差别能被起始的不安的全部的变化的立方体围住，这被证明。

简介：这份报纸与随机的系数为随机的系统涉及混合H2/H控制，它实际上是把H2优化与H2/H的名字揭示的H柔韧的性能相结合的控制。基于古典理论线性二次(LQ短)最佳的控制，为不定的向后的随机的Riccati方程的答案的存在和唯一的足够、必要的条件(BSRE，为短)把坚韧性与H联系了被导出。然后，为H2/H控制的存在的足够、必要的条件被给利用一双联合随机的Riccati方程。

简介：我们使用Ringel大厅代数学途径为在Xi被描绘的类型B2的量组学习正规基础元素[12]。然而，我们的途径在那里简化几计算。

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.

简介：Inthiswork,syngasmethanationoverNi-W/TiO2-SiO2catalystwasstudiedinafluidized-bedreactor(FBR)anditsperformancewascomparedwithafixed-bedreactor(FIXBR).Theeffectsofmainoperatingvariablesincludingfeedstockgasesspacevelocity,cokecontent,bedtemperatureandsulfur-tolerantstabilityof100hlifewereinvestigated.ThestructureofthecatalystswascharacterizedbyXRD,N2adsorptiondesorptionandTEM.Itisfoundthatundersamespacevelocityfrom5000h1to25000h1FBRgaveahigherCH4yield,lowercokecontent,andlowerbedtemperaturethanthoseobtainedinFIXBR.Ni-W/TiO2-SiO2catalystpossessedexcellentsulfur-tolerantstabilityonthefeedstockgaseslessthan500ppmH2SinFBR.ThecarbondepositsformedonthespentcatalystwereintheformofcarbonfibersinFBR,whileintheformofdenseaccumulationdistributionappearanceinFIXBR.

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