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简介：本周，余姚中国塑料城塑料原料市场出现剧烈震荡。周初，基本上是延接上周的迅猛涨势，把市场价格进一步推高，特别是ABS树脂等性塑料，市场气氛上升到近年来的最高峰。周二，市场上刮起一阵冷风，传出降价的消息，造成市场一阵恐慌，在个别小销售商中即出现在压价抛售现象。实际上这是空穴来风，因为由于前期的塑料原料价格上涨的速度太快，涨幅过大，作适当回调这在市场运营中是正常现象。而且目前市场基本面的形势仍然太好，尽管下游市场的支持力度相对较弱，但得到上游市场强有力的支撑，外盘坚挺，国际油价还在继续攀高，国内石化生产厂家并没有出台下调出厂价格的举措。因此，经过短暂的骚动后，下半周的市场已趋平稳。

简介：针对110kV站5^#主变压器的故障，从故障现象、修理简述、初步分析、深入分析等四个方面进行了分析研究，并对此提出了今后应当在大型电气设备中运用的一些经验与教训。

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简介：Inthisresearch,thedegradationofdibenzothiophene(DBT)wasinvestigatedbyusingPseudomonassp.LKY-5isolatedfromoilcontaminatedsoil.Theresponsesurfacemethodology(RSM)basedontheBox-Behnkendesign(BBD)wasappliedforevaluatingtheinteractiveeffectsoffourindependentvariablesincludingsubstrateconcentration,temperature,pHandagitationrateontheDBTremovalresponse.Atotalof29experimentsforfourfactorsatthreelevelswereconductedinpresentstudy.Asecond-orderregressionmodelwasthendeveloped,andtheanalysisofvariance(ANOVA)illustratedthattheproposedquadraticmodelcouldbeutilizedtonavigatethedesignspace.Thevalueofdeterminationcoefficient(R2=0.9534)indicatedasatisfactoryagreementbetweenthequadraticmodelandtheexperimentaldata.ItwasfoundthatDBTremovalwasmoresignificantlyaffected(P<0.0001)bysubstrateconcentrationcomparedwithotherthreeparameters.An100%degradationofDBTcouldbeobtainedbyPseudomonassp.LKY-5atasubstrateconcentrationof100mg/L.

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简介：到2005年我国塑料管总产量将达120万t，其中聚乙烯管48万t。从市场需求看，我国还需要发展一批产量在万吨以上的聚乙烯管材、管件厂。

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简介：FreshZSM-5zeolitecatalystswerepretreatedat460℃and500℃withvariouscumulativeamountofwaterfeed(CAWF)inafixedbedreactor.Thecatalyticprocesswascarriedoutunderthefollowingconditions:atemperatureof480℃;amethanolWHSVof3h-1;amethanolpartialpressureof30kPa;andatimeonstreamof12h,24hand48h,respectively.TheBETparametersofcatalystsanddiffusioncoefficientsoftolueneshowedthatthereweretwotypesofmesoporesgeneratedunderdifferenthydrothermalconditions.MildtemperatureandmoderateCAWFconditionsledtoexternalopenmesoporeswhichcouldbeenteredfromtheexternalsurfaceofthezeolite,whileahightemperatureorahighCAWFconditionresultedinthegenerationofmacroporesorinternalisolatedmesopores,whichwereoccludedinthemicroporousmatrix.TheTGAresultsshowedthatcatalystwithexternalopenmesoporeshadgoodabilitytoresistcokeaccumulationandgoodperformanceonpropyleneselectivity,whiletheinternalisolatedmesoporesdidnocontributetotheincreaseddiffusivityofreactantsandproducts.

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简介：综述了近年来ZSM-5沸石分子筛的合成及表面改性研究进展.合成方面重点介绍了有机胺合成、无机胺合成及负载合成方法;表面改性方面重点介绍了水蒸气改性、离子交换改性及化学气相沉积改性方法.

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.

简介：<正>ZSM-5/MCM-41compositemolecularsievewaspreparedbythenano-assemblingmethod.TheZSM-5molecularsieve,theMCM-41molecularsieve,theZSM-5/MCM-41mechanicalmixtureandtheZSM-5/MCM-41compositemolecularsievewerecharacterizedbyX-raypowderdiffractometry,N2adsorptionisotherms,temperatureprogrammeddesorptionofammoniaandscanningelectronmicroscopyandtheirpropertieswereanalyzed.UsingFCCgasolineasthefeed,activitiesofdifferentmolecularsievesforreducingolefincontentwereinvestigatedinacontinuoushigh-pressuremicro-reactorunitunderthefollowingconditions:areactiontemperatureof400℃,areactiontimeof2h,aweighthourlyspacevelocityof3h-1,andareactionpressureof2.0MPa.TheresultsshowedthattheHMCM-41molecularsievehadlowreactionperformance,andtheHZSM-5molecularsievedemonstratedhigharomatizationactivity,whiletheZSM-5/MCM-41compositemolecularsieveexhibitedabestolefin-reducingperformancebecauseofitshighisomerizationactivityandmoderatearomatizationactivity.Withalargestolefin-reducmgcapabilityandareasonabledistributionofproducts,thecompositemolecularsievewasmoresuitableforFCCgasolineupgradingcomparedtootherthreecatalysts.

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