简介：Weperformfirst-principlecalculationsforthestudyoftheorthorhombicRb2Cd2(SO4)3structure.Electronicenergybands,totalandpartialdensitiesofstatesarereportedandanalysed.Itisfoundthatoxygenatomic2pelectronsstronglyhybridizewithRb/orCd4dandS2pstates,resultingintwo-typeionicgroupswithweakcouplings.Itisshownthatmacroscopicdomainwallsoriginatefromsuchweak-couplingionicgroups,arisingatthecellboundaries.Theasymmetriccationbonds(Rb-OandCd-O)andthesubsequentrotationsoftheS04tetrahedracanleadtothedrivingforceoftheferroelectricbehaviour.Thepredictedpyroelectriccurrenteffectsareobservedexperimentallyintheferroelectricphase.
简介：Kineticsofchloride/sulfate,chloride/nitrateandnitrate/sulfateforwardexchangesandreverseexchangesatsolutionconcentrationsof1N,0.2Nand0.02Non201×7strongbaseanionexchangeresin,respectively,havebeenexaminedat25℃.Itisfoundthattheforwardandthereverseexchangeratesofthetwogivenionsatlowsolutionconcentration,respectively,underidenticalconditionscanbecontrolledbydifferentmechanisms,whilethoseathighsolutionconcentrationareallcontrolledbyparticlediffusion.Theternaryexchangeratesofsulfate/(chloride+nitrate)andnitrate/(chloride+sulfate)havealsobeenexamined.
简介：ThespinelLiMn2O4-x(SO4)xcompoundcathodematerialsweresynthesizedbysolid-statereactionofthecalculatedamountsofLiOH·H2O,MnO2andMnSO4.Theresultsoftheelectrochemicaltestdemonstratedthatthesematerialsexhbitedexcellentelectrochemicalproperties.Thehighestreversiblecapacityoftheseseriesofcathodematerialswas-120mAh/g,andafter50cycles,thisreversiblecapacitywasstillaround116mAh/gwithnearly100%reversibleefficiency,whichrevealedthatdopedsulfateioncouldimprovethestructuralstabilityofspinel.
简介：TiO2nanoparticlesweresynthesizedbyahomogeneouscontrolledprecipitationmethodusingindustrialtitaniumsulfate(Ti(SO4)2).TheobtainedpowderswerecharacterizedbyX-raydiffraction(XRD),transmissionelectronmicroscope(TEM),Fouriertransforminfraredspectroscopy(FTIR)andICPplasmaspectrometer.EDTAwasusedascomplexingagenttoimprovethepurityandtheformationofTiO2nanoparticles.Experimentalresultsindicatedthatthehigh-purityTiO2nanoparticleswere20nminmeansizeandnearlymonodispersed.
简介：ThecrystalgrowthprocessofZn(Leu)SO4·0.5H2OformwaterandacetonewasinvestigatedusingaCalvetmicrocalorimeter.Theheatandtherateofheatproductionduringthecrystalgrowthprocessat293.15K,295.15K,298.15Kand300.15Kweremensured.Onthebasisofexperimentalandcalculatedresults,therateconstantandthekineticparameters(theactivationenergies,thepre-exponential)duringthecrystalgrowthprocesswereobtained.Theresultsshowthatthecrystalgrowthprocesswereobtainged.TheresultsshowthatthecrystalgrowthprocessaccordedwiththeBurton-Cabrera-Franddislocationtheory.
简介：Inthispaperwereportachemicaloscillationcatalyzedby[Ni(Me2[14]1,3-dieneN4)]2+(Me2[14]l,3-dieneN4denotes2,3-dimethyl-l,4,8,ll-tetraazacyclotetradeca-1,3-diene)inBrO3--pyruvicacid-H2SO4system.Thedomainoftheexistenceoftheoscillationwasobtained.Theeffectsofinitialconcentrationofthecomponentsontheoscillationwerestudied.Thefeaturesoftheoscillationsweredescribedindetail.WealsoexaminedtheeffectsofAg+,Hg2+,CCl4,freeradicalinhibitors,etc.ontheosillations.
简介：Treatmentof4-amino-3-(1-aryl-5-methyl-1,2,3-triazol-4-yl)-5-mercapto-1,2,4-triazoles/2-amino-5-(1-aryl-5-methyl-1,2,3-triazole-4-yl)-1,3,4-thiadiazoleswithbenzaldehyde,acetoneandω-bromoacetophenonewastestedandcompared.ThetitlecompoundsSchiffbases,amides,imidazolo[2,1-b]-1,3,4-thiadiazolesand7H-s-triazolo[3,4-b]-1,3,4-thiadiazineshavebeenconfirmedbyelementalanalyses,^1HNMR,IRandMSspectra.AllthecompoundshavealsobeenscreenedfortheirantibacterialactivitiesagainstB.subtilis,S.aureusandE.coli.
简介：Layereddoublehydroxides(LDHs)withhydrotalcite-typestructurecontainingFe3+,Al3+andMg2+werepreparedbymeansofacoprecipitationmethod.Theproductswerecharacterizedbyelementanalysis,X-raypowderdiffractionandtransmissionelectronmicroscopy.Itwasfoundthatevenifthemolarratioofn(Fe+Al)/n(Fe+Al+Mg)>0.33,yetapurehydrotalcite-likecompound(HTlc)phasewasgainedwhenn(Fe)/n(Al+Mg+Fe)≤0.30andn(Al)/n(Al+Mg+Fe)≤0.30;theAl(OH)3phaseappearedintheproductswhenn(Al)/n(Al+Mg+Fe)>0.30;andanamorphousphaseemergedwhenn(Fe)/n(Al+Mg+Fe)>0.33.TheseresultsshowthatthereisnoconcentrationsuperpositioneffectbetweenFe3+andAl3+onthecrystallinestateoftheproducedsamples.Inourpreviouswork,theconcentrationsuperpositioneffectbetweenZn2+andMg2+inthesynthesisofZn-Mg-Al-LDHswasfound.ForthepreparedFe-Al-Mg-LDHssamples,thevalueoflatticeparameteraisbetween0.30-0.32nm;andthevalueoflatticeparametercisbetween2.30-2.47nm,thebasalspacingisintherangeof0.76-0.83nm.Whentheratioofn(Fe)/n(Al)isaconstant,thevaluesofaandcincreasewiththeincreaseoftheMg2+contentoftheproducedsamples.Themeanparticlesizeandthemeancrystalgrainweredeterminedbyvirtueofaparticle-sizeinstrument,XRD-ScherrerformulaandTEMmethod,respectively.
简介：ＳＹＮＴＨＥＳＩＳ ＡＮＤ １８３Ｗ ＮＭＲ ＣＨＡＲＡＣＴＥＲＩＺＡＴＩＯＮ ＯＦ Ｐ４Ｗ３０Ａｌ４（Ｈ２Ｏ）２Ｏ１１２２０－ ＨＥＴＥＲＯＰＯＬＹＡＮＩＯＮＳＹＮＴＨＥＳＩＳＡＮＤ１８３ＷＮＭＲＣＨＡＲＡＣＴＥＲＩＺ?..
简介：CuO/γ-Al2O3catalystswerepreparedbyplasmatreatmentandconventionalimpregnationmethods.Thecatalyticcombustionoftwokindsofvolatileorganiccompounds(VOCs),tolueneandbenzene,werecarriedoutovertheseCuO/γ-Al2O3catalysts.ThesurfacepropertiesofthesecatalystswerecharacterizedbyX-rayDiffraction(XRD)andScanningElectronMicroscopy(SEM).TheexperimentalresultsshowedthatincatalyticcombustiontheactivityoftheCuO/γ-Al2O3catalystpreparedviaplasmawasmuchhigherthanthatoftheCuO/γ-Al2O3catalystpreparedbyconventionalimpregnationmethod.XRDresultsshowedthatanenhanceddispersionhadbeenachievedwiththeplasmatreatment.SEMresultsindicatedthatthesizebecamemuchsmallerandthesurfacebecamemoreuniformwiththeplasmatreatment.
简介：Themonomericcobalt-phosphite-thiolatocomplex[Co(mpt)2{P(OCH3)3}2]BF4(Hmpt=2-mercaptothiazoline)hasbeenpreparedandcharacterizedbyX-raycrystallography.ThecomplexcrystallizesinthemonoclinicspacegroupC2/cwitha=0.8078(5),b=2.6020(18),c=1.2191(7)nm,β=99.38(1)°,V=2.528(3)nm3,andZ=4.Thestructurecomprisesdiscretecations[Co(mpt)2{P(OCH3)3}2.]+andanionsBF4-,inwhichthecobalt(Ⅲ)atomiscoordinatedtotwochelatempt-andtwoas-orientedmonodentateP(OCH3)3ligandsinahighlydistortedoctahedralgeometry.ThemostdistortedanglesareS(2)-Co(1)-S(2a)of162.23(10)°andN(1)-Co(1)-S(2)of71.47(13)°,thelatteriscausedbythegeometricconstraintofthebidentateligandmpt-.CyclicvoltammetryhasbeenusedtostudytheelectrochemicalbehaviorofthetitlecomplexontheRelectrodeinMeCNsolutionwith0.1mol·L-1ofBun4NBF4aselectrolyte.TheresultsindicatethatthetitlecomplexisunstableinMeCN.
简介：Thetitlecompounds5a-5cwerepreparedviathereactionofmethyl2-perfluoroal-kynoates(4)withmethyl5-oxo-4-(triphenylphosphoranylidene)hex-2-enoate(3),whichwasobtainedfromthereactionofmethylpropynate(2)withacetylmethylenetriphenylphosphorane(1)at-5-0℃.IntramoleculareliminationofPh3POtookplacewhencompound5washeatedinaqueousmethanolat115-120℃insealedtube,yieldingdimethyl2-trifluoromethyl-4-methylisophthalate(6a)from5aandmethyl5-acetyl-4-hydroxy-2-heptafluoropropanylbenzoate(6b)from5b,respectively.Thestructuresofcompounds5,6aand6bwereconfirmedbyIR,MS,1HNMR,19FNMRand13CNMRspectroscopyandelementalanalyses.Rectionmechanismsfortheformationofcompounds5,6aand6bwereproposed.
简介：<正>Inthisnote.wewillshowthatnononuniformlatticeofSO（3,1）canbethefundamentalgroupofaquasi-compactKhlermanifold.Thus,combiningwiththeresultin[1].onegetsthatanonuniformlatticeinSO（n,1）（n≥3）cannotbeπ1ofanyquasi-compactKhlerianmanifold.
简介：3-(2-Hydroxyphenyl)-6-(4-nitrophenyl)-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazine,C16H11N5O3S,waspreparedbythecyclizationof3-(2-hydroxyphenyl)-4-amino-5-mercapto-1,2,4-triazolewith2-bromo-4-nitroacetophenone.Thecompoundwascharacterizedbymeansofelementalanalysis,IR,1HNMR,13CNMR,massspectrometry,andX-raydiffraction.ThecompoundcrystallizesinamonoclinicsystemwithspacegroupCc,a=2.1853(4)nm,b=2.1192(5)nm,c=1.3526(3)nm,β=95.21(2)°,V=6.238(2)nm3,Dcalcd.=1.505Mg/m3,Z=16,F(000)=2916,R1=0.0501,wR2=0.0427.Acomparisonbetweenthecrystalstructuresof1,2,4-triazolo[3,4-b][1,3,4]thiadiazineand1,2,4-triazolo[3,4-b][1,3,4]thiadiazolewasmadeinthestructuralview.Atwo-dimensionalnetworkisformedbyhydrogenbondsandπ-πstackinginteractions.
客服QQ：30444492琼网文【2021】1550-113号
增值电信业务经营许可证：琼B2-20210322
出版物经营许可证：新出发龙华出字第(2021)009号
广播电视节目制作经营许可证：(琼)字第00779号
版权所有 ©2002-2024 期刊网(www.qikanchina.com) 琼ICP备2021005105号
![A chemical oscillating reaction in NaBrO<b style='color:red'>3</b>-pyruvic acid-H<b style='color:red'>2</b><b style='color:red'>SO</b><b style='color:red'>4</b>-[Ni（Me<b style='color:red'>2</b>[14]1,3-diene N<b style='color:red'>4</b>）]<b style='color:red'>2</b>+ system](/image/thesis5 "A chemical oscillating reaction in NaBrO<b style='color:red'>3</b>-pyruvic acid-H<b style='color:red'>2</b><b style='color:red'>SO</b><b style='color:red'>4</b>-[Ni（Me<b style='color:red'>2</b>[14]1,3-diene N<b style='color:red'>4</b>）]<b style='color:red'>2</b>+ system")
![Synthesis of （S）-<b style='color:red'>2</b>-（<b style='color:red'>3</b>-Arylacrylamido）-<b style='color:red'>3</b>-{<b style='color:red'>4</b>-[<b style='color:red'>2</b>-（5-methyl-<b style='color:red'>2</b>-phenyloxazol-<b style='color:red'>4</b>-yl）ethoxy]phenyl}propanoic Acids](/image/thesis8 "Synthesis of （S）-<b style='color:red'>2</b>-（<b style='color:red'>3</b>-Arylacrylamido）-<b style='color:red'>3</b>-{<b style='color:red'>4</b>-[<b style='color:red'>2</b>-（5-methyl-<b style='color:red'>2</b>-phenyloxazol-<b style='color:red'>4</b>-yl）ethoxy]phenyl}propanoic Acids")
![Synthesis of Novel Binuclear Samarium Thiolate Complexes [（THF）<b style='color:red'>3</b>I<b style='color:red'>2</b>Sm（μ-SAr）]<b style='color:red'>2</b> （Ar=Ph, <b style='color:red'>4</b>-Me<b style='color:red'>2</b>NC6H<b style='color:red'>4</b>） and Crystal Structure of [（THF）<b style='color:red'>3</b>I<b style='color:red'>2</b>Sm（μ-S-<b style='color:red'>4</b>-Me<b style='color:red'>2</b>NC6H<b style='color:red'>4</b>）]<b style='color:red'>2</b>](/image/thesis10 "Synthesis of Novel Binuclear Samarium Thiolate Complexes [（THF）<b style='color:red'>3</b>I<b style='color:red'>2</b>Sm（μ-SAr）]<b style='color:red'>2</b> （Ar=Ph, <b style='color:red'>4</b>-Me<b style='color:red'>2</b>NC6H<b style='color:red'>4</b>） and Crystal Structure of [（THF）<b style='color:red'>3</b>I<b style='color:red'>2</b>Sm（μ-S-<b style='color:red'>4</b>-Me<b style='color:red'>2</b>NC6H<b style='color:red'>4</b>）]<b style='color:red'>2</b>")
![Synthesis and crystal structure of [Co（mpt）<b style='color:red'>2</b>{P（OCH<b style='color:red'>3</b>）<b style='color:red'>3</b>}<b style='color:red'>2</b>]BF<b style='color:red'>4</b> （Hmpt = <b style='color:red'>2</b>-mercaptothiazoline）](/image/thesis12 "Synthesis and crystal structure of [Co（mpt）<b style='color:red'>2</b>{P（OCH<b style='color:red'>3</b>）<b style='color:red'>3</b>}<b style='color:red'>2</b>]BF<b style='color:red'>4</b> （Hmpt = <b style='color:red'>2</b>-mercaptothiazoline）")
![Preparation and Crystal Structure of <b style='color:red'>3</b>-（<b style='color:red'>2</b>-Hydroxyphenyl） -6- （<b style='color:red'>4</b>-nitrophenyl）-7H- 1,<b style='color:red'>2</b>,4-triazolo[<b style='color:red'>3</b>,4-b][1, <b style='color:red'>3</b>,<b style='color:red'>4</b>]thiadiazine](/image/thesis16 "Preparation and Crystal Structure of <b style='color:red'>3</b>-（<b style='color:red'>2</b>-Hydroxyphenyl） -6- （<b style='color:red'>4</b>-nitrophenyl）-7H- 1,<b style='color:red'>2</b>,4-triazolo[<b style='color:red'>3</b>,4-b][1, <b style='color:red'>3</b>,<b style='color:red'>4</b>]thiadiazine")
![Crystal Structure and Bioactivity of Complex [Gd（C10H9N<b style='color:red'>2</b>O<b style='color:red'>4</b>）（C10H8N<b style='color:red'>2</b>O<b style='color:red'>4</b>）（H<b style='color:red'>2</b>O）<b style='color:red'>3</b>]<b style='color:red'>2</b>·phen·<b style='color:red'>4</b>H<b style='color:red'>2</b>O](/image/thesis18 "Crystal Structure and Bioactivity of Complex [Gd（C10H9N<b style='color:red'>2</b>O<b style='color:red'>4</b>）（C10H8N<b style='color:red'>2</b>O<b style='color:red'>4</b>）（H<b style='color:red'>2</b>O）<b style='color:red'>3</b>]<b style='color:red'>2</b>·phen·<b style='color:red'>4</b>H<b style='color:red'>2</b>O")
![Synthesis and Crystal Structure of a <b style='color:red'>2</b>D Honeycomb-like Polymeric Cluster （Et<b style='color:red'>4</b>N）<b style='color:red'>3</b>{[MoS<b style='color:red'>4</b>Cu<b style='color:red'>2</b>（μ-CN）]<b style='color:red'>2</b>（μ＇-CN）}·<b style='color:red'>2</b>MeCN](/image/thesis19 "Synthesis and Crystal Structure of a <b style='color:red'>2</b>D Honeycomb-like Polymeric Cluster （Et<b style='color:red'>4</b>N）<b style='color:red'>3</b>{[MoS<b style='color:red'>4</b>Cu<b style='color:red'>2</b>（μ-CN）]<b style='color:red'>2</b>（μ＇-CN）}·<b style='color:red'>2</b>MeCN")