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130 个结果
  • 简介:Abosonicconstruction(withcentralchargec=2)ofLiealgebrasW1+∞andW1+∞(glN),aswellasthedecompositionsintoirreduciblemodulesaredescribed.AndforW1+∞,whenrestrictedtoitsVirasorosubalgebraVir,abosonicconstructionandthesamedecompositionforVirareobtained.

  • 标签: 玻色子表示法 李代数 Virasoro超代数 不可约模数
  • 简介:IntroductionTungsten-copperalloypowdersareusedinmanyfieldsonaccountofthehighelectricandthermalconductivitiesofcopperandhighmeltingpointoftungsten.W-Cupowders,aspreparedconventionallybymeansofinfiltration,hasthedisadvantageofinhomogeneityinmicrostructure,andaredifficulttoworkwithaftersintering.

  • 标签: 微观结构 特征 钨-铜合金粉末 活性 高能球磨 机械磨碎法
  • 简介:Inthispaper,wegetW1,p(Rn)-boundednessfortangentialmaximalfunc-tionandnontangentialmaximalfunction,whichimprovesJ.Kinnunen,P.LindqvistandTananka’sresults.

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  • 简介:对化合物[Na_2(H_2O)_(10)][Cu_4(H_2O)_(12)(H_2W_(12)O_(42))]·15H_2O(简称Na_2Cu_4W_(12))进行了体外抗肿瘤活性研究.应用四甲基偶氮唑盐(3-[4,5-dimethylthiazo-2-y]-2,5-diphenyltetrazoliumbromide,MTT)比色法分析Na_2Cu_4W_(12)对人肝癌细胞(HepG2)、人神经母细胞瘤细胞(SHY5Y)增殖抑制活性.采用光学显微镜观察肿瘤细胞的凋亡形态变化,用流式细胞术分析细胞周期和细胞凋亡,计算各期细胞比例及细胞凋亡率.结果表明,Na_2Cu_4W_(12)对HepG2和SHY5Y2种肿瘤细胞增殖半数抑制浓度IC_(50)值分别为5.3和10.2μmol·L~(-1),且呈剂量依赖性.光学显微镜下处理组细胞出现皱缩、变圆、缩小等形态变化,不同浓度Na_2Cu_4W_(12)处理12h早期凋亡细胞所占的百分比显著增加且呈剂量依赖性.综上所述,Na_2Cu_4W_(12)能够抑制胞瘤细胞增殖,诱导细胞凋亡.

  • 标签: 仲钨酸盐化合物 抗肿瘤 体外研究
  • 简介:At-hyperwheel(t≥3)oflengthl(orW(t)lforbrevity)isat-uniformhypergraph(V,E),whereE={e1,e2,...,el}andv1,v2,...,vlaredistinctverticesofV=∪eii=1lsuchthatfori=1,...,l,vi,vi+1∈eiandei∩ej=P,j∈/{i1,i,i+1},wheretheoperationonthesubscriptsismodulolandPisavertexofVwhichisdifferentfromvi,1≤i≤l.Inthispaper,theminimumcoveringproblemofMCλ(3,W(3)4,v)isinvestigated.DirectandrecursiveconstructionsonMCλ(3,W(3)4,v)arepresented.Thecoveringnumbercλ(3,W(3)4,v)isfinallydeterminedforanypositiveintegersv≥5andλ.

  • 标签: 最小覆盖问题 一致超图 递归结构 Tgt 直接和 覆盖数
  • 简介:SYNTHESIS AND 183W NMR CHARACTERIZATION OF P4W30Al4(H2O)2O11220- HETEROPOLYANIONSYNTHESISAND183WNMRCHARACTERIZ?..

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  • 简介:Inthecontextoftopcolor-assistedtechnicolor(TC2)model,westudythechargedandneutraltop-pionsproductionprocessγγ→W~+П_t~-П_t~0.Wefindthattheproductioncrosssectionislargerthanthatoftheprocessγγ→W~+H~-Hintheminimalsupersymmetricstandardmodel.WithreasonablevaluesoftheparametersintheTC2model,thecrosssectioncanreachthelevelofafewfb.Furthermore,theflavor-changing(FC)decaymodeП_t~0→tcisthebestchanneltodetecttheneutraltop-pionduetothecleanSMbackground.Withalargenumberofeventsandthecleanbackground,theneutraltop-pionshouldbeobservableatfuturelinearcollidersoperatinginγγmodeattheTeVenergyscale.

  • 标签: 标准模型 直线对撞机 生产过程 衰变模式 amp 介子
  • 简介:WesuggesttwoschemestogeneratetheWstateofNA-typethree-levelatoms.Intheschemes,identicalNthree-levelatomsaretrappedinacavityorNdistantcavities.ThesuccessorfailureofthegenerationoftheWstatecanbedeterminedbydetectingthepolarizationofphotonleakingoutofthecavity.TheresultdemonstratesthattheWstateisfreefromboththecavitylossandthespontaneousemissionduetothefactthatthetwogroundstates(leftandright)ofthethree-levelatomsarestablestates(ormetastablestates).

  • 标签: 原子物理学 ∧型三层原子结构 光子干涉 W态 单腔 量子纠缠态
  • 简介:WedemonstrateamonolithicsinglefrequencyTm-dopedfiberamplifierwithoutputpowerof51.5W.Asinglefrequencyfiberlaserat1.97μmisamplifiedbyacascadedmasteroscillatorpoweramplifier(MOPA)systemwithall-fiberconfiguration.Theoptical-to-opticalconversionefficiencyofthemainfiberamplifieris45%.Noamplifiedspontaneousemission(ASE)orstimulatedBrillouinscattering(SBS)effectisobservedinthefiberamplifier.Theoutputpowercouldbefurtherscaledbylaunchingmorepumppower.

  • 标签: Single frequency Tm-doped FIBER laser FIBER
  • 简介:Theresearchacceleratorsaregrowinginenergyandpowerwhichinducesanincreaseoftheprojectcosts(Fig.1).TheRFcavitiesandpowersupplymainlycontributethecostofthesuperconductinglinac,whichisacompetitivetechnologyforhighpowermachine.AcodewithoptimizationalgorithmisdevelopedtooptimizethebetavalueofSCcavityfamilyandtransitionenergytoincreasetheTTFvalueofthewholelinac.

  • 标签: SUPERCONDUCTING LINAC
  • 简介:ThefirststarsintheearlyUniversewereformedabout400millionyearsafterthebigbang.VerificationoftheexistenceofthesestarsisimportantforourunderstandingoftheevolutionoftheUniverse[1].IthasbeenpredictedthatforPopulation-IIIstellarproductionyields,theabundancesofodd-Zelementsareremarkablydeficientcomparedtotheiradjacenteven-Zelements[2].Astronomersaresearchingforlong-lived,lowmassstarswiththeuniquenucleosyntheticpatternmatchingthepredictedyields[3].

  • 标签: FIRST DIRECT MEASUREMENT
  • 简介:Thispaperprovesthattheoptimalquadratureformulasoftype(r1,…rn)forWm1isunique,andtheextremalfunctionischaracterizedbyitsoscillatoryproperty.Ontheotherhand,thefundamentaltheoremofalgebraforperiodicmonosplineswithoddmultiplicitiesissolvcd

  • 标签: QUADRATURE OSCILLATORY algebra FORMULAS UNIQUENESS whenever
  • 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。

  • 标签: N-TiO2 光催化剂 共掺杂 场发射扫描电子显微镜 光驱动 傅里叶变换红外光谱