学科分类
/ 25
500 个结果
  • 简介:Anenvironmentallyfriendlyprecursor,adenosine,hasbeenusedasadualsourceofCandNtosynthesizenitrogen-dopedcarboncatalystwith/withoutFe.Ahydrothermalcarbonizationmethodhasbeenusedandwateristhecarbonizationmedia.Themorphologyofsampleswith/withoutFecomponenthasbeencomparedbyHRTEM,andtheresultshowsthatFecanpromotethegraphitizationofcarbon.Furtherelectro-chemicaltestshowsthattheoxygenreductionreaction(ORR)catalyticactivityofFe-containingsample(C–FeN)ismuchhigherthanthatoftheFe-freesample(CN).Additionally,theintermediatesofC–FeNformedduringeachsyntheticprocedurehavebeenthoroughlycharacterizedbymultiplemethods,andthefunctionofeachprocedurehasbeendiscussed.TheC–FeNsampleexhibitshighelectro-catalyticstabilityandsuperiorelectro-catalyticactivitytowardORRinalkalinemedia,withitshalf-wavepotential20mVlowerthanthatofcommercialPt/C(40wt%).Itisfurtherincorporatedintoalkalinepolymerelectrolytefuelcell(APEFC)asthecathodematerialandledtoapowerdensityof100mW/cm~2.

  • 标签:
  • 简介:<正>在亚洲的东方,巍然屹立着一个泱泱大国。在她广袤的土地上,孕育着一代代黄皮肤的龙的传人,演绎着无尽的风云传奇。她的辉煌让人侧目,人们在晨曦中瞥见她的侧影,轻吐她的名字:"C—H—I—N—A"。

  • 标签: 风云传奇 龙的传人 C-H-I-N-A 华夏子孙 勤劳勇敢 摇曳多姿
  • 简介:TheeffectofTi(C,N)onpropertiesoflow-carbonMgO-Cbrickswasinvestigated.Thephasecompositionandthemicrostructureofthematrixoflow-carbonMgO-CbrickcontainingTi(C,N)werestudiedbyXRDandSEManalysistogetherwithEDS.TheresultsshowedthatTi(C,N)distributedinthematrixoflow-carbonMgO-Cbrickuniformlyafterbeingtreatedat1600℃for3hincokepowderbed,andTi(C,N)andMgOformedasolidsolution.Afterthetreatmentat1600℃for3hincokepowderbed,thebulkdensityandcoldcrushingstrengthoflow-carbonMgO-CbrickwithTi(C,N)decreased,andtheapparentporosityandlinearchangerateofspecimensincreased.Theoxidationresistanceoflow-carbonMgO-CbrickwithTi(C,N)wassuperiortothatoflow-carbonMgO-Cbrickwithnoadditives,butinferiortothatoflow-carbonMgO-CbrickwithAlpowder.TheslagresistanceofthespecimenwithTi(C,N)wasexcellentaswell.

  • 标签: MGO-C砖 氧化强度 耐火材料 建筑材料
  • 简介:摘要在进行混凝土质量控制的时候,高性能混凝土配合的设计是非常重要的部分,好的配合设计能够有效地确保高性能混凝土的质量,同时也能够更好地保障整体工程项目建设。因此在进行高性能混凝土配合设计的时候,需要有效地控制设计要点,并采取有效的措施进行控制,从而更好地满足设计要求,确保高性能混凝土的质量,最大程度地发挥其功效。基于此,分析了高性能混凝土配合的设计要点以及质量控制。

  • 标签: C50 混凝土 配合比 设计
  • 简介:摘要 本工程位于山东沿海地区,沿路横跨小清河等河流,水下桩的侵蚀性很强,本试验室的所需攻克的技术难关就是设计选定合适的高性能混凝土施工配合

  • 标签:
  • 简介:采用新颖的碳热还原和氮化前驱体法制备Ti(CN)晶须,通过X射线衍射仪(XRD)、扫描电子显微镜(SEM)对样品表征分析,结果表明,在1250℃条件下,产物主要相成分是Ti(CN)晶须,含有少量的Ni和TiN成分,晶须直径为100~200nm,反应温度低于1250℃时,钛的氧化物还原不充分,而过高的温度也不能促进Ti(CN)纳米晶须的形成。

  • 标签: Ti(C N)晶须 碳热还原 前驱体
  • 简介:QUALITATIVESTUDYOFSIALOMUCINSCHANGESDURINGN-METHYL-N-NITROSOUREA-INDUCEDCOLONICCARCINOGENESISINMICEWangQiang王强;WangYuanhe王元和;...

  • 标签: Experimental COLONIC NEOPLASM Sialomucin MUCIN histochemistry.
  • 简介:在纳米科学中,材料的性质与其分子结构相关,可通过拓扑指数计算得到其物理化学性质.作为一种常见结构,纳米管结已被广泛应用于材料科学及相关工程中.因此,有必要计算它对应分子结构的化学指数,结果给出纳米管结Cas(C)-CaR(C)[m,n,p]的几类基于度的化学指数的精确计算公式.作为补充结论,研究了H-环烃纳米片[4n,2m]的第四原子键连通指数.所得理论结果在材料制造工程中具有潜在的应用价值.

  • 标签: 理论材料 分子图 拓扑指数 纳米管结
  • 简介:ThesubmicronpowdermixturesofTiC-TiN-WC-Mo-C-Nisinteredat1400℃orbelowinvacuumwerestudiedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM)andtransmissionelectronmicroscopy(TEM)analyses.TheresultsshowedthatMo2Cformedat800℃orbelow.BothWCandMo2Cdisappearedat1200℃,andTiNdisappearedat1250℃.Inaddition,thevariationsoflatticeconstantsofthetitaniumcarbonitrideandnickelbinderphasewithsinteringtemperaturewereexperimentallyobtained,andthereasonwasanalyzed.

  • 标签: SUBMICRON CERMET PHASE SINTERING
  • 简介:Thec-JunN-terminalkinases(JNKs)areclassicstress-activatedproteinkinases.ManycellularstresseshavebeenshowntostimulateJNKactivation.Inthisreview,wefocusonribotoxicstressesbasedontheirmultiplebiologicalpotenciesincludinganti-HIV-1activity.Someofthefunctionsofribotoxinsandthesignalingtransductionpathwaythatmediatedarementioned.Differentfromotherstimulators,ribotoxicstressesactonspecialmotifsof28SrRNAintranslationallyactivemammalribosomes.BindinganddamagingonthemotifleadstoJNKactivationandsubsequentlybiologicalresponsetothesignalinitiator,whichisnamedribotoxicstressresponse.

  • 标签: N-端激酶 细胞凋亡 核糖体 爱滋病病毒