学科分类
/ 25
500 个结果
  • 简介:有N-(2-propionic酸)的新奇金轧(III)建筑群-salicyloylhydrazone(C10H10N2O4,H3L)并且1,10-phenanthroline(C12H8N2,phen)被准备并且描绘。水晶结构[Gd(H2L)(HL)-(H2O)3]2潲楰湯捩???慳楬祣潬汹?票牤穡湯??ㄠ??桰湥湡桴潲楬敮???????楢慯瑣癩瑩?

  • 标签: 邻二氮杂菲 晶体结构 X射线衍射 三斜晶系
  • 简介:TheAl2O3-SiCcompositepowderswerepreparedinargonatmosphereusingcoalgangueandcarbonaceousmaterials2O3-SiCcompositepowderswereinvestigated.Theresultsindicatethat:temperature,soakingtimeandchlorideadditivehavesignificantinfluenceonthesynthesizedAl2O3-SiCcompositepowders.Basedontheresults,theoptimizedAl2O3-SiCcompositepowders(Al2O358mass%andSiC42mass%)withparticlesized50≤5μmwerepreparedusingcoalgangueandcarbonblackasstartingmaterialsafter3hfiringat1550℃.andproperadditiveadditioncouldreducethetemperatureby50℃.

  • 标签: 碳化硅微粉 还原合成 碳热还原 氧化铝 煤矸石 复合粉末
  • 简介:Twooxo-vanadium(IV)complexes,[VO(C2O4)(2,2′-bipy)(H2O)]·C2H5OH(1)andVO(C2O4)(phen)(H2O)(2),where2,2′-bipy=2,2′-bipyridyl,phen=1,10-phenanthroline,weresynthesizedaspotentialfunctionalmodelsofvanadiumhaloperoxidases(VHPOs)inmixedsolventofethanolandwateratroomtemperature.Thecomplexeswerecharacterizedbyelementalanalysis,infrared(IR),UV-VisandX-raycrystallography.Structuralanalysesshowedthatvanadiumatomwascoordinatedbyaterminaloxygen,oneoxygenatomfromcoordinatedwater,twooxygenatomsfromthecarboxylategroupofoxalicacid,andtwonitrogenatoms(N1andN2)from2,2′-bipy/phen.Centralvanadiumatomsincomplexes1and2werebothinadistorted-octahedralenvironment,andsomeintermolecularhydrogenbondinglinkageswerealsoobservedineachcomplex.BrominationreactionactivityofthetwocomplexeswasevaluatedwithphenolredasorganicsubstrateinthepresenceofH2O2,Br-andphosphatebuffer,indicatingthattheycanbeconsideredasapotentialfunctionalmodelofVHPO.Inaddition,thermalanalysiswasalsoperformedanddiscussedindetail.

  • 标签: 过氧化物酶 模型化合物 结构表征 溴化反应 氧钒 仿生催化
  • 简介:Chemical-loopingcombustion(CLC)isanovelcombustiontechniquewithinherentCO2separation.Magnetite(Fe3O4)wasselectedastheoxygencarrier.Shenhuacoal(InnerMongolia,China),strawcokeandnaturalcokewereusedasfuelsforthisstudy.Influencesofoperationtemperatures,coaltoFe3O4massratios,anddifferentkindsoffuelsonthereductioncharacteristicsoftheoxygencarrierwereinvestigatedusinganatmospherethermogravimetricanalyzer(TGA).Scanningelectronmicroscopy(SEM)wasusedtoanalysethecharacteristicofthesolidresidues.Experimentalresultsshownthatthereactionbetweenthecoalandtheoxygencarrierbecomestrongatatemperatureofhigherthan800℃.Astheoperationtemperaturerises,thereductionconversionrateincreases.Atthetemperaturesof850oС,900℃,and950℃,thereductionconversionrateswere37.1%,46.5%,and54.1%respectively.However,SEMimagesshowthatatthetemperatureofhigherthan950℃,theironoxidesbecomemeltedandsintered.Thepossibleoperationtemperatureshouldbekeptaround900℃.WhenthemassratiosofcoaltoFe3O4were5/95,10/90,15/85,and20/80,thereductionconversionrateswere29.5%,40.8%,46.5%,and46.6%respectively.Withtheincreaseofcoal,theconversionrategoesup.Butthereexistanoptimalratioaround15/85.Comparisonsbasedondifferentkindsoffuelsshowthatthesolidfuelwithahighervolatileandamoredevelopedporestructureisconducivetothereductionreactivityoftheoxygencarrier.

  • 标签: 扫描电子显微镜 操作温度 固体燃料 Fe3O4 扫描电镜照片 四氧化三铁
  • 简介:SYNTHESIS AND 183W NMR CHARACTERIZATION OF PW30Al(HO)O11220- HETEROPOLYANIONSYNTHESISAND183WNMRCHARACTERIZ?..

  • 标签:
  • 简介:有不同外部直径的CuFe2O4nanotube数组通过技术由加热处理进程跟随了的大音阶的第五音胶化在阳极的铝氧化物模板被综合。nanotube数组的形态学被扫描电子显微镜和传播电子显微镜学的地排放调查,建议nanotube数组被订并且制服。X光检查衍射结果显示nanotube数组的水晶结构与尖晶石类型结构是多晶的。磁性的大小显示有200nm的外部直径的CuFe2O4nanotube数组沿着nanotubes的轴与容易的磁化方向展出磁性的anisotropy。

  • 标签: 碳纳米管阵列 场发射扫描电子显微镜 透射电子显微镜 X-射线衍射 尖晶石型结构 热处理过程
  • 简介:本文报道了C6H12O6(NHSOCH5OHHO(CH5OH/HO=0.90)体系在35℃时体系溶解度和饱和溶液的折光指数,并绘出了体系相应的溶度图和饱和溶液的折光指数曲线图。结果表明:所研究的体系为四元体系C6H12O6(NHSOCH5OHHO中的一部分。当溶液中肌醇饱和时,溶度曲线落在约50%的等醇水比面上。当(NHSO在溶液中达到饱和时,出现共饱点。其组成为(NHSO10%,C6H12O6:2.08%,CH5OH:4475%。同时出现分层,在富醇相随着乙醇浓度的增加,出现肌醇与硫酸铵共饱线。在富水相硫酸铵饱和溶度曲线落在约5%乙醇的等醇水比面上,折光指数曲线由三支组成,其中两条分别与C6H12O6·HO和(NHSO相对应,另外一条线与(NHSO和C6H12O6·HO的共饱线相对应

  • 标签: 三元体系 溶解度 肌醇 硫酸胺 乙醇
  • 简介:用扫描电镜、X-射线衍射、等离子体原子发射光谱、热重分析、循环伏安、恒电流充放电、交流阻抗法研究了溶胶-凝胶法合成的尖晶石锂锰氧化物的物理化学性能,并与熔盐法合成样品作了比较.熔盐法制备的样品的颗粒为不规则块状,初始容量低(99.6mAh/g),而溶胶-凝胶法制备样品的颗粒细小、均匀,初始容量较高(112.5mAh/g).但是熔盐法制备的样品经30次循环后容降为15%,而溶胶-凝胶的却高达40%.熔盐法制备的样品中实际Li/Mn为0.506,与原料中Li/Mn摩尔比相近,而溶胶-凝胶法只有0.473,比原料中的小.熔盐法制备的样品为纯尖晶石结构,而溶胶-凝胶法制备的有杂相Mn2O3生成.热处理过程中部分Li的挥发损失和非电化学活性Mn2O3的生成导致锂锰氧化物容量快速下降.

  • 标签: 锂锰氧化物 溶胶-凝胶法 容降
  • 简介:采用TG—DSC方法研究了K3[Al(C2O4)3]·3H2O与K3[Cr(C2O4)3]·3H2O两个配合物的热分解反应过程,对其中部分热解过程进行了动力学计算。由Friedman、Ogaw8一Flynn—Wall、ASTME698三种方法得出峰温时的活化能值与指前因子值.应用Aehar方法计算拟合得到了比较合理的机理函数.

  • 标签: 热分析 热解动力学 铝草酸配合物 铬草酸配合物
  • 简介:Theoccurrencemodesofalkaliandalkaline-earthmetals(AAEMs)incoalrelatetotheirreleasebehaviorandashformationduringcombustion.TobetterunderstandthetransformationofAAEMs,thereleasebehaviorofwater-soluble,HCl-soluble,HCl-insolubleAAEMsduringShenmucoal(SMcoal)oxy-fuelcombustioninthepresenceofSO2andH2Oinadrop-tubereactorwasinvestigatedthroughserialdissolutionusingH2OandHClsolutions.TheresultsshowthatthereleaseratesofAAEMsincreasewithanincreaseintemperatureunderthethreeatmospheresstudied.ThehighreleaseratesofMgandCafromSMcoalaredependentonthehighcontentofsolubleMgandCainSMcoal.SO2inhibitsthereleaseratesofAAEMs,whileH2Opromotesthem.TheeffectsofSO2andH2OontheNaandKspeciesaremoreevidentthanthoseonMgandCaspecies.AllthreetypesofAAEMsincoalcanvolatilizeinthegasphaseduringcoalcombustion.TheW-typeAAEMsreleaseexcessively,whereasthereleaseratesofI-typeAAEMsarerelativelylower.DifferenttypesofAAEMmayinterconvertthroughdifferentpathwaysundercertainconditions.BothSO2andH2Opromotethetransformationreactions.TheeffectofSO2wasrelatedtosulfateformationandthepromotionbyH2OoccursbecauseofadecreaseinthemeltingpointofthesolidaswellasthereactionofH2O.

  • 标签: 富氧燃烧 碱土金属 神木煤 碱金属 管式反应器 HCL溶液
  • 简介:本文用[Mn3O(O2CCH:CHCH3)6(py)3]ClO44,4'-二甲基-2,2'联吡啶在CHaCN溶液反应,合成了一个四核的锰配合物[Mn4O2(O2CCH:CHCH3)7(Me2bipy)2]ClO4.对化合物进行了元素分析及红外表征,在2,2-300K温度范围内测定了其变温磁化率,实验结果表明化合物存在反铁磁性交换作用.

  • 标签: 四核锰配合物 ClO4 合成 磁性质 磁性材料 表征
  • 简介:WehavesynthesizedandinvestigatedphysicalpropertiesoftwonewquaternarycompoundsGd2CoAl4T2(T=Si,Ge)singlecrystals,whichareisostructuraltoTb2NiAl4Ge2andEr2CoAl4Ge2.Themostimportantstructuralfeatureofthesematerialsistheanti-CaF2-typeCoAl4T2slabs.Thesematerialsshowmetallicbehaviorbelow300Kandthereisalong-rangeantiferromagnetic(AFM)transitionappearingat20and27KforGdCoAl4Ge2andGd2CoAl4Si2,respectively.ResistivityandheatcapacitymeasurementsalsoconfirmthesebulkAFMtransitions.Furtheranalysisindicatesthatthislong-rangeantiferromagnetismshouldresultfromthemagneticinteractionbetweenlocalmomentsofGd^3+ions.

  • 标签: magnetic MAT erials RARE earth COMPOUNDS
  • 简介:Thecombinationofboth4,4′-bipyridine(4,4′-bipy)anddihydrogenphosphateanionligandswithcopper(Ⅱ)resultsintheformationofanovellayeredcompoundCu(4,4′-bipy)2(H2PO4)2(H2O)2.ThecrystalstructurecomprisesdiscreteneutralCu(4,4′-bipy)2(H2PO4)2(H2O)2units.Thecopperatom,locatedonthecrystallographictwofoldaxis,iscoordinatedwithtwonitrogenatomsofterminal4,4′-bipyligandsandtwowatermoleculesattheequatorialpositions,andtwodihydrogenphosphateoxygenatomsattheaxialpositions,forminganelongatedoctahedron.Thecomplexisatwo-dimensionaldistortedrhomboidalnetworkpossessingtwokindsofrhomboidswithdimensionsofca.1.6792nm×0.3203nmand1.2778nm×0.3198nm,respectively.Thetwo-dimensionalnetworksarestackedparallellyoneachotheralongc-axistogiveanextendedthree-dimensionalchannelnetworkwithaninterlayerdistanceofca.0.5030nm.Crystaldata:triclinic,spacegroupP-1,a=1.0253(2)nm,b=1.4501(3)nm,c=0.79715(16)nm,α=97.91(3)°,β=90.99(3)°,γ=85.54(3)°,V=1.1703(4)nm3,Z=2,R=0.0892,wR=0.2451.

  • 标签: 磷酸盐 4 4'-双吡啶 铜(Ⅱ)复合物 沟渠构造 热液合成
  • 简介:CO2methanationhasbeenahottopicbecauseofitsimportantapplicationinthespacecraftandpotentialutilizationofcarbondioxide.Nickelcatalystisactiveforthisreaction.However,itsactivitystillneedstobeimproved.Dielectricbarrierdischarge(DBD)plasma,initiatedatambientconditionandoperatedat~150°C,hasbeenemployedinthisworkfordecompositionofnickelprecursortoprepareNi/MgAl2O4.Theplasmadecompositionresultsinhighdispersion,uniquestructure,enhancedreducibilityofNiparticlesandpromotedcatalyst-supportinteraction.AnimprovedactivityofCO2methanationwithahigheryieldofmethanehasbeenachievedovertheplasmadecomposedcatalyst,comparedtothecatalystpreparedthermally.Forexample,themethaneyieldoftheplasmapreparedcatalystis71.8%at300°Cbutitis62.9%overthethermalpreparedcatalyst.ThecatalystcharacterizationconfirmedthatCO2methanationovertheDBDplasmapreparedcatalystfollowspathwayofCOmethanation.

  • 标签: 甲烷化反应 分解催化剂 等离子体 二氧化碳 镍催化剂 介质阻挡放电
  • 简介:无机化学实验中Cr2O3溶于浓硫酸的内容,其目的是试验并证明铬的氧化物的两性,接铬元素所在周期表的位置,其正常氧化物应能溶于酸和碱中,即属两性氧化物。对这一问题,我们查阅了有关资料,发现各有不同说法,计有下列三种不同叙述,一是载Cr2O3可溶于酸亦可溶于碱;二是载Cr2O3能溶于酸,但不溶于碱;三是载Cr2O3不溶

  • 标签: 无机化学实验 两性氧化物 CR2O3 H2SO4 酸和碱 三氧化二铬
  • 简介:ElectrocrystallizationMechanismofTungsteninMoltenKF-B_O_3-K_WO_WenZhenhuanandLiGuoxun文振环,李国勋(GeneralResearchInstiiuteforNo...

  • 标签: ELECTROCRYSTALLIZATION mechanism TUNGSTEN Electrodeposition Mol-ten KF-B2O3-K2WO4