简介：

简介：Theimportantintermediateforsynthesesofvariousanti-HIVnucleosideanalogues,methyl2,3-dideoxy-3-fluoro-6-O-(p-methylbenzoyl)-a-D-ribofuranoside,wassynthesizedstartingfrom2-deoxy-D-ribosein5stepswithanoverallyieldof24%.Thisstrategycanbealsousedforsynthesizingotheranalogueswithvarioussubstitutionsat3-Cposition.

简介：

简介：Thenanomaterialsoftenexhibitveryinterestingelectrical,optical,magnetic,andchemicalproperties,whichcannotbeachievedbytheirbulkcounterparts[1-7].Thedevelopmentofuniformnanometersizedparticleshasbeenintensivelypursuedbecauseoftheirtechnologicalandfundamentalscientificimportance[8-15].Itissignificantthatnanostructuredmaterialscanbecontrollablyassembledintotherequiredgeometryontosubstrates,becomingthebasisofthenextgenerationofcomponentsanddevices[16-31].Thedevelopmentofnewmethodsandstrategiesfororganizingthenanoparticlebasicbuildingblocksintothedesiredstructuresisrequired.Superlatticesmadefromthesebuildingblocksgiveustheopportunitytostudynotonlythepropertiesoftheindividualbuildingblocks,butalsocollectiveeffects.Thesuperparamagneticironoxidenanocrystals(NCs)havebeenusedinthefieldsofbio-medicine,ferrofluids,refrigerationsystem,catalysis,particularlyinmagneticresonanceimaging,tissueengineering,anddrugdeliveryapplications[32-42].

简介：

简介：APt-MoO3/Ccatalyst,aimedtoeliminatetheharmfuleffectofsulfurdioxide（SCb）ontheperformanceofPtnanoparticles（NPs）forcatalysisofoxygenreductionreaction（ORR）inprotonexchangemembranefuelcells（PEMFC）,isdevelopedandcharacterizedbyTEM,XRDandXPS.TheresultsrevealthatPt-MoO3/Ccatalystexhibitsnotonlyahighercatalyticactivity,butalsoabetterSO2poisoningresistanceandabetterrecoveryperformancethanthecommercialPt/Ccatalystdoes.

简介：TheoptoelectronicandmagneticpropertiesofpureHoMnO3andHo0.67T0.33MnO3(T=La,Y)alloysinhexagonalphasearetheoreticallyinvestigatedbyusingthefirst-principlescalculations.TheinvestigationsareperformedbymeansofthedensityfunctionaltheorythroughusingthespinpolarizedgeneralizedgradientapproximationplustheHubbardpotential(SPGGA+U,Ueff=3eV).ThestudiedmaterialHoMnO3exhibitstwoindirectbandgaps:1.58eVforthespinupstateand0.72eVforthespin-downstatealongtheS–GdirectionwithintheSPGGA+Uapproximation.ItisfoundthatthebandgapofpureHoMnO3forthespin-upstateincreaseswithincreasingLaandYdopants.Theresultsshowthatallofthestudiedmaterialshavesemi-metallicbehaviorsforthespin-upstateandsemiconductingcharacterforthespin-downstate.ThesubstitutionsofLaandYforHoinHoMnO3causethestaticdielectricconstant(ε0)toincreaseinthexdirectionbuttodecreaseinthezdirection.ThecalculatedopticalconductivityspectrumofHoMnO3inalowenergyrangeisingoodagreementwiththerecentexperimentaldata.

简介：为了推进，从抗菌剂fluoroquinolone(FQ)为移动扩展一条有效修改线路到antitumorFQ，标题混合物的二个系列基于有二的FQC3羧基的组的isostere熔化了杂环的戒指，[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine和pyrazolo[5,1-c][1,2,4]分别地，triazole被设计并且综合了从当前的抗菌剂FQ开始，并且他们的在里面对L1210的vitroantitumor活动，CHO房间线经由他们的各自的IC被评估

简介：

简介：Ａ　Ｎｅｗ　Ｅ３　Ｔｒａｎｓｉｔｉｏｎ　ｆｒｏｍ　９＋　Ｉｓｏｍｅｒ　ｉｎ　１４４Ｐｍ　ＮｕｃｌｅｕｓＡＮｅｗＥ３Ｔｒａｎｓｉｔｉｏｎｆｒｏｍ９＋Ｉｓｏｍｅｒｉｎ１４４ＰｍＮｕｃｌｅｕｓ￥ＺｈａｎｇＹｕｈｕ；Ｙ．Ｇｏｎｏ；ＺｈａｏＱｉｎｚ...

简介：假设c是一个小于1/1152的常数，证明：对于每个充分大的偶数n，如果一个具有n个顶点的3一致完全超图的边着色满足每种颜色出现的次数不超过[cn]，那么必含有一个每条边颜色都不一样的彩色哈密顿圈。

简介：Extractionofthein-mediumpropertiesofstrangeparticlesfromheavy-ioncollisionsisverycomplicated,sincehenucleardensityvariesintheevolutionofnucleus-nucleuscollisions.Toavoidtheuncertaintiesofthebaryonensitiesduringthestageofstrangeparticleproduction,onecaninvestigateproton-nucleuscollisionswheretheucleardensityisdefinitearoundthesaturationdensity.DynamicsofstrangeparticlesproducedintheprotoninduceduclearthereactionsnearthethresholdenergieshasbeeninvestigatedwithintheLanzhouquantumoleculardynamics(LQMD)transportmodel.Thein-mediummodificationsonparticleproductionindensenuclearmatterareconsideredthroughthecorrectionstotheelementarycrosssectionsviatheeffectivemassandhemean-fieldpotentials[1].

简介：Nanowireshaveattractedmoreandmoreinterestinrecentyearsduetotheiruniquepropertiescomparedtobulkmaterials[1].Thequitedifferentpropertiespossessedbynanowiresaremainlycausedbytheirhighsurface-tovolumeratio[2].Behaviorsofnanowiresunderirradiationconditionshavealsoattractedintensiveattentionintheseyears[3??5].Ithasbeenproposedthatnanowiresmayberadiationresistancebecausetheirlargesurface-to-volumeratio,andmeanwhilethesurfacearetheperfectsinksfordefectscreatedintheradiationprocess[3].

简介：Sweetsorghum,theworld'sfifthmostimportantcerealafterrice,corn,wheatandbarley,isaveryattractivesourceforbiomassproduction.Thisrawmaterialcomplementssugarcaneproductionandisemergingastheidealfeedforanimalsandfortheproductionofthefirst-generationofbiofuels,suchasethanolandvalue-addedchemicals.Atpresent,mostofthestudiesaboutsweetsorghumfocusonutilization(suchasethanolproduction),andthestudyofsugeraccumulationinstemarerarely.

简介：Parametersforthe3W1sourceatBSRFweredeterminedinboththededicatedandparasiticmodeandtheirsuitabilityforproteincrystallographybeamlineatBSRFwererealized.Itisdiscussedthatthephysicsmotivationandthedesignofthe3W1iscomparedwithsimilarexperimentalstationsattheBrazilianLightSourec(1.37Gev)andMax-IIinSweden(1.5GeV).Thephotonfluxfromthe3W1sourcdisabout2×10^11photon/smAinthewavelengthrangeof2.0-0.9Ainparasiticmodeand50-80timeshigherinthededicatedmode.Boththededicatedandparasiticmodesaresuitableformacromolecularstructureexperiments.2001ElsevierScienceB.V.Allrightsreserved.

简介：在Alq(3)层的洞传导性上做的2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane(F4TCNQ)的效果被测量。在Alq(3)的洞唯一的设备，当前的密度在与F4TCNQ做之上在1-3数量级增加，建议做的罐头有效地提高Alq(3)的洞注射和洞运输能力。用F4TCNQ的一台器官的轻射出的设备做了Alq(3)洞注射和洞运输层，和太古的Alq(3)作为电子运输和射出的层被制作并且描绘的层。明亮的排放作为电子运输和射出的层作为洞运输层和内在的Alq(3)与做p的Alq(3)在简单OLED被完成。设备的射出的效率和亮度被插入薄电子块层在器官的层的中间限制搬运人再结合地区进一步改进。

简介：

简介：

简介：

简介：Comparativemolecularfieldanalysis(CoMFA),athreedimensionalquantitativestructure-activityrelationship(3D-QSAR)methodwasappliedtoaseriesofdiindolylmethane(DIM)analogstostudytherelationshipbetweentheirstructureandtheirinductionofCYP1A1-associatedethoxyresorufin-O-deethylase(EROD)activity.ADISCOmodelofpharmacophorewasdervedtoguidethesuperpositionofthecompounds.Thecoefficientofcross-validation(q^2)andnoncross-validation(r^2)forthemodelestablishedbythestudyare0.827and0.988respectively,thevalueofvarianceratio(F)is103.53andstandarderrorestimate(SEE)is0.044.ThesevaluesindicatethattheCoMFAmodelderivedissignificantandmighthaveagoodpredictionforthecatalyticactivityofDIMcompounds.Asaconsequence,thepredictedactivityvaluesofnewdesignedcompoundswereallhigherthanthatofthereportedvalue.