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  • 简介:Inthepastfewdecades,manynovelnon-metaldopedZnOmaterialshavedevelopedhastyinterestduetotheiradaptablepropertiessuchaslowrecombinationrateandhighactivityunderthesolarlightexposure.Inthisarticle,wecompiledrecentresearchadvancesinnon-metal(S,N,C)dopedZnO,emphasizingontherelatedmechanismofcatalysisandtheeffectofnon-metalsonstructural,morphological,opticalandphotocatalyticcharacteristicsofZnO.ThisreviewwillenhancetheknowledgeabouttheadvancementinZnOandwillhelpinsynthesizingnewZnO-basedmaterialswithmodifiedstructuralandphotocatalyticproperties.

  • 标签: DEGRADATION recombination MECHANISM PHOTOCATALYST POLLUTANT
  • 简介:ThepolycrystallinephaseWO3/g-C3N4wassynthesizedunderstirringusingtungstenicacid(H2WO4)andgraphiticcarbonnitride(g-C3N4)asrawmaterials.ThecatalystwascharacterizedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM),energydispersivespectroscopy(EDS),theFouriertransforminfraredspectroscopy(FT-IR),andtheBrunauer-Emmett-Telleranalysis(BET).ThepolycrystallinephaseWO3/g-C3N4wasdeterminedbyXRDtechnique.TheoxidativedesulfurizationprocesswasinvestigatedusingWO3/g-C3N4asthecatalyst,30%hydrogenperoxide(H202)astheoxidant,and1-butyl-3-methylimidazoliumtetrafluoroborate([bmim]BF4)ionicliquids(ILs)astheextractant.Theoperatingconditions,includingH2WO4amount,ILdose,H2O2volume,temperature,catalystdosage,andtypesofsulfurcompounds,weresystematicallyresearched.Thedesulfurizationratecouldreach98.46%forremovingdibenzothiophene(DBT)fromthemodeloilunderoptimalreactionconditions.Inaddition,thecatalyticactivitywasslightlydecreasedafterfiverecyclesofcatalysts.Thereactionkineticsanalysisshowsthattheoxidativedesulfurizationsystemwasinaccordwiththefirst-orderreactionkineticsequation.Themechanismofoxidativedesulfurizationwasproposed.

  • 标签: oxidative DESULFURIZATION WO3/g-C3N4 heterogeneous CATALYSIS EXTRACTANT
  • 简介:Low-energypartial-waveπNscatteringdataisreexaminedwiththehelpoftheproductionrepresentationofpartial-waveSmatrix,wherebranchcutsandpolesarethoroughlyunderconsideration.Theleft-handcutcontributiontothephaseshiftisdetermined,withcontrolledsystematicerrorestimates,byusingtheresultsofO(p^3)chiralperturbativeamplitudesobtainedintheextended-onmass-shellscheme.InSnandPuchannels,severediscrepanciesareobservedbetweenthephaseshiftdataandthesumofallknowncontributions.Statisticallysatisfactoryfitstothedatacanonlybeachievedbyaddingextrapolesinthetwochannels.WefindthataSnresonancepolelocatesat√zr=(0.895±0.081)—(0.164±0.023)iGeV,onthecomplexs-plane.Ontheotherhand,aFnvirtualpole,asanaccompanyingpartnerofthenucleonbound-statepole,locatesat√zv=(0.966±0.018)GeV,slightlyabovethenucleonpoleontherealaxisbelowthreshold.Physicaloriginofthetwonewlyestablishedpolesisexploredtothebestofoiirknowledge.ItisemphasizedthattheO(p^3)calculationgreatlyimprovesthefitqualitycomparingwiththepreviousO(p^2)one.

  • 标签: dispersion RELATIONS πN scatterings NUCLEON RESONANCE
  • 简介:摘要通常认为,“N来了”与“来N了”中前一个N属于无定,后一个N属于有定,这一说法并不完全正确。文章从生成语法的角度,分析了“来N了”的移位过程,得出了N移位是为了成为焦点的结论。针对部分无法完成移位的N,文章也进行了梳理。对其中一类无法完成移位却在句首表示无定的N的情况进行了分析。研究发现,这部分N都是需要重读的成分。由于汉语非屈折语,因此无法利用形态获得焦点,排除了移位的方法,N只能通过语音重读的方式成为焦点。成为焦点后的N虽然位于句首,但带有焦点性质,于是便是新信息了。

  • 标签: &ldquo N来了&rdquo 与&ldquo 来N了&rdquo 移位 焦点 语音
  • 简介:采用粉末冶金法制备Ti(C,N)基金属陶瓷,研究粘结相Co与Ni的含量比对材料组织结构和性能的影响,并系统研究材料在高温环境和酸性水溶液中的氧化与腐蚀行为。结果表明,w(Co)/w(Ni)=1的金属陶瓷材料T3具有优异的综合力学性能,其抗弯强度与硬度(HRA)分别为1749MPa和93.8;随着Ni的添加,材料在H2SO4溶液中的耐腐蚀性能显著提高,其中的T3经120h浸泡腐蚀后质量损失率为0.0745%,粘结相和部分环形相的溶解为金属陶瓷在酸溶液中的主要腐蚀行为。随w(Co)/w(Ni)的值减小,材料阳极极化过程中不同钝化区出现融合,证明Ni含量增加可促进元素向粘结相中的固溶,T3材料具有优异的耐腐蚀性能,自腐蚀电流密度为3.3566×10^-7A/cm^2。表面积为2.5cm^2的Ti(C,N)基金属陶瓷,在900℃高温静态空气中氧化10h后,质量增加量均小于1mg,材料的氧化机理以粘结相优先氧化和富Ti、W固溶相的氧化腐蚀为主。

  • 标签: w(Co)/w(Ni) TI(C N)基金属陶瓷 浸泡腐蚀 电化学腐蚀 高温氧化
  • 简介:摘要“N1+的+N2”结构是一个具有潜在歧义可能性的抽象的格式,例如在日常生活中,像“医生的父亲”之类的歧义结构有很多。本文便将以该格式为研究对象,尽可能的列举其所有结构并对它们进行深入细致的描写,从语法研究的三个平面阐释其各个类型歧义产生的原因,分析在什么样的条件下可能产生歧义、什么样的条件下不会产生歧义,从而剖析句法、语义和认知因素在此结构中的影响作用。

  • 标签: &ldquo N1+的+N2&rdquo 歧义结构 原因
  • 简介:Thesuppressionoftherecombinationofelectronsandholes(e–h)andtheenhancementofthelightabsorptionofsemiconductorsaretwokeypointstowardefficientphotocatalyticdegradation.Here,wereportafew-layerg-C3N4/α-MoO3nanoneedles(flg-C3N4/α-MoO3NNs)all-solid-stateZ-schememechanismphotocatalystsynthesizedviaatypicalhydrothermalmethodinacontrolledmanner.Therecombinationofthephoto-inducede–hpairscouldbeeffectivelyrestrainedbytheZ-schemepassagewaybetweentheflg-C3N4andα-MoO3NNsinthecomposite,whichcouldalsopromiseahighredoxabilitytodegradepollutants.Anditbecamepossibleforthepreparedphotocatalysttoabsorblightinawiderangeofwavelengths.Thedetailedmechanismwasstudiedbyelectronspin-resonancespectroscopy(ESR).Thelow-dimensionalnanostructureofthetwoconstituents(α-MoO3NNswithone-dimensionalstructureandflg-C3N4withtwo-dimensionalstructure)endowedthecompositewithvarietiesofexcellentphysicochemicalproperties,whichfacilitatedthetransferanddiffusionofthephotoelectronsandincreasedthespecificsurfaceareaandtheactivesites.The10wt%flg-C3N4/α-MoO3NNsshowedthebestphotocatalyticperformancetowardRhBdegradation,therateofwhichwas71.86%,~2.6timeshigherthanthatofα-MoO3NNs.

  • 标签: Flg-C3N4 α-MoO3 NANONEEDLES ALL-SOLID-STATE Z-scheme mechanism
  • 简介:  8例闭合骨折,8例为闭合骨折(其中4例伴有其它多部位骨折),股骨髁间粉碎骨折固定方法较多

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  • 简介:摘要n-BiTAC是一种先进的复极式电解槽,结构简单、独特。电解槽的槽电压是反应电解装置运行状况好坏的主要指标之一,直接影响电解产品的生产成本。现航锦科技股份有限公司12万t/a烧碱装置,已运行至第二个膜周期,但在运行过程中发现,第二个膜周期槽电压升高速度比第一个膜周期快,且最高电压已超过第一个膜周期的最高电压。

  • 标签: 电槽 膜周期 电压
  • 简介:摘要当前我国C2C模式下电子商务的税收法律法规并不完善,子商务在税收征管过程中仍存在的问题,最后针对存在的问题提出了相对应的解决措施,以期为电子商务模式下税收征管的进一步发展带来一定的参考价值。

  • 标签: 电子商务 C2C 税收征管
  • 简介:2018年已经过去,如果用一个汉字来描述自己的这一年,可能每个人都有不同答案。如果用一个汉字来形容一个国家的2018,哪个字会夺得'C位'呢?由中国国家语言资源监测与研究中心主办的'汉语盘点2018'评选,选出的中国年度代表字为'奋'。

  • 标签: 马来西亚
  • 简介:Variousagriculturalcropresiduesincludingcornstover,corncob,andsorghumstalkwithamoisturecontentof75wt%weresubjectedtoalongpretreatment(12-60h)withsupercriticalCO2(scCO2),atlowtemperature(50-80℃)andapressureof17.5-25.0Mpa.Thesugaryieldsfromtheenzymatichydrolysis(EH)ofthepretreatedsampleswereasmuchasthree-tofourfoldgreaterthanthoseaffordedbytherawmaterials.However,whenpretreatmentwasconductedwithinashorttime(e.g.0.5h),aspreviouslyreportedintheliterature,onlyaslightincreaseintheEHsugaryieldswasobserved.TheproposedscCO2pretreatmentmechanismdemonstratedtheroleofmoistureinthesystem.Wetting,softening,andswellingwereobservedtomainlyaffectthelignocellulosewhenasuitableamountofwaterwasadded.Finally,thesampleswereanalysedbyX-raydiffractionandscanningelectronmicroscopy,beforeandafterpretreatment,toinvestigatethechangesinthemicroscopicstructureofthebiomass.

  • 标签: LIGNOCELLULOSE scCO2 PRETREATMENT ENZYMATIC HYDROLYSIS SUGAR
  • 简介:SiliconoxynitridewasaddedinshapedAl2O3-SiC-Crefractorymaterialtoimprovetheslagresistanceinthispaper.Optimumaddingquantityofsiliconoxynitridepowderwasalsostudied.TheresultsshowthattheslagresistanceofAl2O3-SiC-Cshapedrefractoryisimprovedwhen2%or3%Si2N2Oisadded.AreasonableamountofSi2N2OaddedintoAl2O3-SiC-Cshapedrefractorycanproducesiliconoxideintotheslag,whichcanimprovetheviscosityofslagandpreventtheslagerosionandpenetration.

  • 标签: SLAG resistance SILICON OXYNITRIDE alumina-silicon carbide-carbon
  • 简介:摘要n-BiTAC是一种先进的复极式电解槽,结构简单、独特。电解槽的槽电压是反应电解装置运行状况好坏的主要指标之一,直接影响电解产品的生产成本。现航锦科技股份有限公司12万t/a烧碱装置,已运行至第二个膜周期,但在运行过程中发现,第二个膜周期槽电压升高速度比第一个膜周期快,且最高电压已超过第一个膜周期的最高电压。

  • 标签: 电槽 膜周期 电压
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  • 简介:宝宝的成长.有着很多的角度。绘本中的故事.告诉他们各种各样的经历和收获,帮助他们感受快乐的时光。

  • 标签: 绘本 宝宝 快乐
  • 简介:摘要目的富马酸喹硫平中的N,N-二甲基苯胺成分作为一种毒性杂质,随药品进入人体,会对人体内的细胞造成伤害,导致细胞变异,感染引起疾病。为此,本实验通过建立液相色谱-质谱联用方法对富马酸喹硫平中的N,N-二甲基苯胺成分做含量测定,测定富马酸喹硫平中基因毒性杂质N,N-二甲基苯胺的含量。方法本实验采用液相色谱-质谱联用仪作为主要仪器;流动相A为甲醇-缓冲液,流动相B为乙腈-水溶液,进行梯度洗脱,设定流速为每分钟0.5ml,设置柱温60℃;利用三重四级杆串联离子阱液质联用仪以及MultipleReactionMonitori(MRM)模式进行检测,采用正离子模式进行试验数据采集。结果在富马酸喹硫平中,多次取样N,N-二甲基苯胺的含量在0.38ng~8.19ng之间,且与峰面积呈现出一个适当的线性关系,试验得出线性方程为Y=3.58×106X+607,其中r等于0.9994。检测限是0.15ng,定量限是0.45ng。平均加样回收率超过百分之百。结论以质谱联用方法测定富马酸喹硫平中N,N-二甲基苯胺效果明显,可以在试验中使用。

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  • 简介:VisualC#中调用Excel的COM组件 ,要在VisualC#中使用这些非受管代码的COM组件,本文介绍了Excel对象、C#中的受管代码和非受管代码

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  • 简介:Anovelgas-phaseelectrocatalyticcellcontainingalow-temperatureprotonexchangemembrane(PEM)wasdevelopedtoelectrochemicallyconvertCO2intoorganiccompounds.TwodifferentCu-basedcathodecatalysts(CuandCu-C)werepreparedbyphysicalvapordepositionmethod(sputtering)andsubsequentlyemployedforthegas-phaseelectroreductionofCO2atdifferenttemperatures(70-90℃).ThepreparedelectrodesCuandCu-CwerecharacterizedbyX-raydiffraction(XRD),X-rayphotoemissionspectroscopy(XPS)andscanningelectronmicroscopy(SEM).Asrevealed,CuispartiallyoxidizedonthesurfaceofthesamplesandtheCuandCu-Ccathodiccatalystswerecomprisedofaporous,continuous,andhomogeneousfilmwithnanocrystallineCuwithagrainsizeof16and8nm,respectively.Theinfluenceoftheappliedcurrentandtemperatureontheelectro-catalyticactivityandselectivityofthesematerialswasinvestigated.Amongthetwoinvestigatedelectrodes,thepureCucatalystfilmshowedthehighestCO2specificelectrocatalyticreductionratesandhigherselectivitytomethanolformationcomparedtotheCu-Celectrode,whichwasattributedtothehigherparticlesizeoftheformerandlowerCuO/Curatio.Theobtainedresultsshowpotentialinterestforthepossibleuseofelectrical「enewableenergyforthetransformationofCO2intovaluableproductsusinglowmetalloadingCubasedelectrodes(0.5mgCucm2)preparedbysputtering.

  • 标签: C02 VALORIZATION ELECTRO-REDUCTION CU catalyst PEM