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  • 简介:相对增益阵列(RGA)大多数应用的矩阵阶数都是较小的(n=2,3或4).我们从矩阵方程Φ(A)=1/2J2的实数解出发,应用矩阵方程Φ(A)=1/nJn的实数解在G-等价下的不变性和实数解的分块构造法,研究了Φ(A)=1/4J4的实数解的一些问题.

  • 标签: 相对增益阵列 HADAMARD乘积 G-等价 实数解
  • 简介:InthispaperweusedMOF-5andCu3(BTC)2toseparateCO2/CH4andCH4/N2mixturesunderdynamicconditions.Bothmaterialsweresynthesizedandpelletized,thusallowingforameaningfulcharacterizationinviewofprocessscale-up.ThematerialswerecharacterizedbyX-raydiffraction(XRD)andscanningelectronmicroscopy(SEM).Byperformingbreakthroughexperiments,wefoundthatCu3(BTC)2separatedCO2/CH4slightlybetterthanMOF-5.BecausethecrystalstructureofCu3(BTC)2includesunsaturatedaccessiblemetalsitesformedviadehydration,itpredominantlyinteractedwithCO2moleculesandmoreeasilycapturedthem.Conversely,MOF-5withasuitableporesizeseparatedCH4/N2moreefficientlyinourbreakthroughtest.

  • 标签: BTC CO2 混合物 分离 扫描电子显微镜 X射线衍射
  • 简介:Threefold Fragmentation of Hot Compound Nuclei in 25 MeV/40Ar+115In, 103Rh and 93Nb ReactionsThreefoldFragmentatio...

  • 标签: 40Ar FRAGMENT
  • 简介:Hot Nuclei Formation and Decay of 40Ar+209Bi and 40Ar+197Au System at 30MeV/uHotNucleiFormationandDecayof40Ar+(...

  • 标签: 40Ar SYSTEM Form
  • 简介:Thispaperfollowstheworkof[1,2].Therearesomeprogressindealingwithmoderatelysmallrotations(thesquaresofrotationanglesaretheorderofmagnitudeofstrains)ofmiddlesurfacenormalsofinsideandoutsideringshellsandcompressedangleofbellows.Calculationresultsagreewithexperimentswell.Tobellowdesign,themethodgiveninthispaperisofpracticalvalueandthediscussionoftheinfluenceofcompressedangleoncharacteristicrelationishelpful.

  • 标签: U-SHAPED BELLOWS LARGE axisymmetrical DEFLECTION compressed
  • 简介:Radiotherapyisacommontreatmentmodalityforheadandneckcancers,nasopharyngealcancers,primarybraintumorsandbrainmetastases.Alargenumberofpatientsintheworldwithprimaryormetastaticbraintumorswillrequirelargevolumeorwholebrainirradiationeveryyear.However,therapeuticirradiationnotonlykillstumorcells,butalsoinjuresnormalbraintissue,whichiscommonlyassociatedwithsignificantfunctionalmorbidityanddecreasedqualityoflifeinpatientstreatedwithbrainradiotherapy[1].

  • 标签: Protective Effects Hydroxysaffor
  • 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:Opticallyactive(R)-(+)-2,2’-bis(2-trifluoro-4-aminophenoxy)-1,1’-binaphthylwaspreparedfrom1,1’-bi-2-naphthol.Theopticallyactivearomaticpolyimidewasalsosuccessfullysynthesized.Thisnewpolymerhasgoodsolubility,thermalstabilityetc.Itsspecificrotationwasfoundtobe+174°,anditschiropticalpropertywasalsostudied.

  • 标签: Optical ACTIVITY 1 1′-Bi-2-naphthol POLYIMIDE
  • 简介:Achiralrutheniumcomplex[(1S,2S)-DPEN]-RuCl_2(PPh_3)_2(DPEN=1,2-diphenylethylenediamine,PPh_3=triphenylphosphine)wasencapsulatedinthechannelofAl-MCM-41byelectrostaticadsorptionand1,1-dichlorosilacyclobutanemodification.Thepreparedheterogeneouscatalystshowedthesamecatalyticactivityandenantioselectivityasthecorrespondinghomogeneouscatalystintheasymmetrichydrogenationofacetophenone,andcouldbereusedatleastseventimeswithoutsignificantlossofcatalyticactivityandenantioselectivity.

  • 标签: 苯乙酮 MCM 不对称氢化 Al 封装 非均相催化剂
  • 简介:Thesynthesisof(S)-2-(3-arylacrylamido)-3-{4-[2-(5-methyl-2-phenyloxazol-4-yl)ethoxy]phenyl}propanoicacidsisdescribed.TheirstructureswereconfirmedbyH-NMR.

  • 标签: 丙酸 合成方法 分子结构 核磁共振
  • 简介:用微波高温固相法合成了Er^3+单掺Lu2O3,Li^+与Er^3+共掺Lu2O3及Li^+,Zn^2+,Mg^2+掺杂Lu2O3∶Er^3+的荧光粉。实验表明金属离子Li^+、Zn^2+、Mg^2+、Er^3+掺杂Lu2O3,不影响Lu2O3的立方晶相。扫描电子显微镜测量表明,Li^+掺杂可以有效改善粉体的分散性和形貌,Li^+,Zn^2+,Mg^2+共掺杂获得的粉体颗粒分布更加均匀,粒径范围为80~100nm。379nm激发下,Li^+与Er^3+共掺样品发光较单掺Er^3+样品在565nm处的发光增强了4.5倍,而Li^+、Zn^2+、Mg^2+与Er^3+共掺样品较其发光增强5.3倍。980nm激发下,Li^+与Er^3+共掺样品,Li^+、Zn^2+、Mg^2+与Er^3+共掺样品的发光分别比单掺Er^3+样品在565nm处发光增强23倍与39倍,在662nm处发光强度分别增强20倍与43倍。379nm激发下,较单掺Er3+的样品,掺杂Li^+的样品和Li^+,Zn^2+,Mg^2+和Er^3+共掺的样品荧光寿命均有所增加,而Zn^2+、Er^3+共掺及Mg^2+、Er^3+共掺样品的荧光寿命则有所缩短。

  • 标签: 微波高温固相法 Li^+ Zn^2+ Mg^2+掺杂Lu2O3∶Er^3+荧光粉 发光强度 上转换发光 荧光寿命
  • 简介:The2-C,methylenegroupof1-aroyl-1,2-dihydro-3H-naphtho[2,1-b]pyran-3-ones(2)havebeenshowedtopossessasuperiorreactivitytowardsmanyoforganicreagents.Thena-phthopyrones(2)condensedwitharomaticaldehydestogivethe2-arylidinederivatives(3).Bromin-ationof2gave1,2-dibromo(4)or5-bromo(5)derivativesdependingonthereactionconditions.Thebasecatalyzedadditionorcycloadditionofnaphthopyrones(2)to4-methoxybenzalacetophenonegavetheexpectedMichaeladduct(6)orthecyclicadducts(7-9)dependingonthetypeofcatalyticbaseandreactionconditions.Structuresoftheproductshavebeenestablishedbyelementalanalyses,IRand~1HNMRspectroscopicmethods.

  • 标签: PYRAN REACTIVITY aldehydes aromatic bromo catalyzed
  • 简介:Nuclearmassisoneofthefundamentalquantityofatomicnucleus.Thetotalbindingenergyofanucleusderivedfromtherelatedmassvaluesreflectsalltheinteractionsamongtheconstitutingnucleons.Massesofshort-livedA=2Z+3nucleiof112SnprojectilefragmentshavebeenmeasuredattheexperimentalcoolerstorageringCSRe,employingtheIsochronousmassspectrometry(IMS).TheexperimentwasconductedattheHeavyIonResearchFacilityinLanzhouatthebeginningof2016.Theprimarybeamof112Sn35+wasaccumulatedinthesynchrotronCSRmandacceleratedto467.91MeV/u.Secondarybeamwereproducedbyimpingingthehighintensity112Sn35+beamontoa10mmberylliumtargetwhichwaslocatedattheentranceoftheradioactivebeamlineRIBLL2.Theprojectilefragmentsof112Snemergedfromthetargetwerethentransmitted,separatedinflightthroughRIBLL2andfinallyinjectedintoCSRe.

  • 标签:
  • 简介:TheepoxidationofallylchloridewithH2O2onTi-ZSM-5preparedbyisomorphoussubstitutionofHZSM-5withTiCl4gaswasstudied.TheresultsshowthatTi-ZSM-5hasahighcatalyticefficiencyfortheepoxidationofallylchloride.TheH2O2utilizationreaches99.50%whentheallylchloride/H2O2molarratiois>1.Theeffectofsolventspecies,catalystconcentration,H2O2andallylchlorideconcentrationandreactiontemperatureontheepoxidationwasinvestigatedsimultaneously.Itisfoundthatmethanolisthebestsolventforthereaction.Thereactionrateequationwithv=k[Cat.][H2O2]1/2-[C3H5Cl]andtheapparentactivationenergywithEa=63.462kJ/molareobtainedaccordingtothekineticsstudy.

  • 标签: TI-ZSM-5 EPOXIDATION of ALLYL chloride epichloro-hydrin
  • 简介:Weperformfirst-principlecalculationsforthestudyoftheorthorhombicRb2Cd2(SO4)3structure.Electronicenergybands,totalandpartialdensitiesofstatesarereportedandanalysed.Itisfoundthatoxygenatomic2pelectronsstronglyhybridizewithRb/orCd4dandS2pstates,resultingintwo-typeionicgroupswithweakcouplings.Itisshownthatmacroscopicdomainwallsoriginatefromsuchweak-couplingionicgroups,arisingatthecellboundaries.Theasymmetriccationbonds(Rb-OandCd-O)andthesubsequentrotationsoftheS04tetrahedracanleadtothedrivingforceoftheferroelectricbehaviour.Thepredictedpyroelectriccurrenteffectsareobservedexperimentallyintheferroelectricphase.

  • 标签: 轨道杂交 斜方晶结构 氧原子 电子状态 铁电物质 畴壁能量
  • 简介:研究了YBaCu3O6~7超导催化剂上CO的加氢制醇反应。考察了温度、压力和空速等条件对催化剂反应性能的影响。反应的主要产物是甲醇、CO和少量甲醚。利用XPS、XRD和AFM等技术对催化剂的结构、铜的存在状态和反应活性位进行表征发现,在反应过程中,YBaCu3O6~7由orthombic相转变为tetragonal相。反应活性位可能是Cu(I)物种。反应后催化剂颗粒的分散程度明显提高

  • 标签: CO2加氢 YBa2Cu3O6~7超导催化剂 结构 活性位