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简介：介绍了一种2，2－二氯六氟丙烷一元氢解生成2－氯－2－氢六氟丙烷的方法，其过程为：在有效量的负载于三价氧化铬上的钯催化剂及HZ型酸（Z为Cl或F）存在下，于150℃以下的高温下，将2，2－二氯六氟丙烷与氢气反应，生成2－氯－2－氢六氟丙烷，以转化掉的2，2－二氯六氟丙烷计，反应的选择性可达70％以上，还介绍了2－氯－2－氢六氟丙烷与HF形成的共沸物及生成该共沸物的工艺。

简介：以2,2,6,6-四甲基-4-羟基哌啶、烯丙基氯和氢氧化钠为原料催化合成4-烯丙氧基-2,2,6,6-四甲基哌啶,分别研究了反应时间、原料配比、溶剂用量和催化剂用量等条件对合成4-烯丙氧基-2,2,6,6-四甲基哌啶反应的影响,确定的最佳操作条件为：反应温度为45～54℃,反应时间5h,反应物摩尔比为：n（烯丙基氯）∶n（2,2,6,6-四甲基-4-羟基哌啶）∶n（氢氧化钠）为0.45∶0.1∶0.4,溶剂用量为10g,催化剂的用量为0.2g（2,2,6,6-四甲基-4-羟基哌啶为0.1mol）,收率可达到95.43%以上,纯度为99.5%。

简介：β-sialon/alumina/silicamixturesweresinteredinflowingnitrogenat1500℃and1600℃respectively.ThesinteringpropertiesandmorphologyofsampleswereinvestigatedbySEM,EDSandXRD.Resultsshowthatsinteredpropertiesofthesamplesareinfluencedbysoakingtemperaturesandcompositions.Bulkdensitiesofsamplesareincreasedwiththeincreaseofthesoakingtemperature,whereastheapparentporositiesaredecreased.Masslossofthesinteredsamplesat1500℃islowerthanthatat1600℃,butallthemasslossremainsapproximatelyconstantwiththeincreaseofsialoncontent.Fromthepointofthermodynamicanalysis,ComplexchemicalreactionstakeplaceinsamplesduringsinteringprocessandthevolatileofSiO(g)isresponsibleforthemasslossofsamples.Comparedtocrosssectionmicrostructureofβ-sialon/Al2O3/SiO2mixturessinteredincokepowderbedconsistingofthedensecenterwithwell-developedcolumnofsialonphase,thetransitionalpartwithneedlelikegrainnitrogen-containingphaseandtheloosepartwithshortgranularAl2O3phase,thoseofmixturessinteredinflowingnitrogenisofwell-developedsialonindensecenterandslightlyloosepartwithsialondebris.

简介：MicrostructureandgrainboundarycharacterofhotpressedbinaryAl2O3(mullite,ZrO2)-SiCompositesandquaternaryAl2O3-mullite-ZrO2-SiCcompositewerestudiedbyelectronmicroscopyandmicroanalysis,ResultssuggestthatthereexistgrainboundarysolidsolutionsduetoelementaldiffusionnearSiCandmatrixoxidesgrainboundaries.

简介：LowcementAl2O3-SiO2castableswaspreparedusingsupergradebauxite(w(Al2O3)>85%)asaggregate,brownfusedcorundum,siliconcarbide,Secar71CAcement,α-Al2O3micropowderandmicrosilicaasfinepowders.TheinfluenceofSiC(0,5wt%,10wt%,and15wt%)onresistancetoPbO-richslagwasinvestigatedbystaticcrucibleslagtest(1300℃for5h,inair).TheslagcorrosionmechanismofthecastableswasanalyzedbymeansofSEM,EDSandXRD.TheresultsshowthattheresistanceofAl2O3-SiO2castablestoPbO-richslagisimprovedobviouslybytheadditionofSiC.ThecorrosionmechanismofthePbO-richslagcanbediscribedasthatPbOintheslagreactswithSiO2andCaOinAl2O3-SiO2castables,forminglow-meltingcompounds(suchasPbO·SiO2and2PbO·SiO2).

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简介：MgO-Al2O3-Cr2O3rammingmixesmadeofdifferentrawmaterialshavedifferentmineralstructureanddifferentphysicalpropertiesthoughwiththeidenticalparticlesizedistribution,thesameamountofbinderandchemicalcomposition.Theresidualcarboncontentofthefusedmagnesia-chromematerialmadeinreducingatmosphereisveryhigh,ifthismaterialsisusedintheMgO-Al2O3-Cr2O3rammingmix,itwouldcausespallingofthefurnaceliningduringdrying-out.

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简介：<正>一、市场行情简述本月行情:2月,纯MDI市场偏弱整理,节后市场窄幅震荡,贸易商跟随万华纷纷上调报价,下游开工恢复缓慢,处于休市状态,市场有价无市,并无听闻成交,临近中旬,元宵节后,下游大量需求的情况并未涌现,商谈气氛难有活跃,临近月末,下游库企高位,采购兴趣低迷,在最后一日,万华公布挂牌价格,上调500元/吨,挺市的心态明显,商谈的气氛有所回暖。上游原料:纯苯:2月纯苯市场在春节之后,受到节前调价影响,虽价格无基本变化,但下游及贸易商都对于后市并无看好,下游采购积极性偏低,相对于传统往年的节后市场,

简介：HuntsmanTioxide公司自2004年10月1日以来将所有的二氧化钛产品价格上调，出售给全球用户。在美国，除FC5，TR28和所有锐钛型产品上涨0．07美元／lb外，其它所有产品均上涨O．06美元／lb。在加拿大，FC5、TR28和所有锐钛型上涨0．09加元／lb，其它所有产品上涨0．08加元／lb。在欧洲，

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简介：食品级CO2的分析标准提高，原来的分析方法不能适应工艺要求。介绍了一种新的能分析H2S、COS等单组分、精度高、灵敏度高的分析方法——气相色谱法。该方法分析速度快，分离效果好。

简介：MgO-ZrO2unfiredbrickswithZrO2contentupto8%attheintervalof2%wereprepared,usingfusedmagnesia(MgO:97%)andfusedMgO-ZrO2clinker(ZrO2:14.33%)asstartingmaterialsandphenolicresinasbinder.TheeffectsofZrO2contentonthermalshockresistance(TSR)andotherpropertiessuchascoldandhotmodulusofrupturehavebeeninvestigated.Residualcoldmodulusofruptureratioafterheatingat1000℃andquenchingbyairblowingwasadoptedtocharacterizeTSR.AdditionoftheMgO-ZrO2clinkerimprovesTSR,attributingtothemicrocracktougheningeffectbythermalexpansionmismatchbetweendifferentphases.WhenZrO2contentgoesabove4%,theimprovingeffecttendstobemoderate.TheintroductionofMgO-ZrO2clinkercanalsoimprovetheHMORat1500℃,whiletheincreasedZrO2contentreducesCMORofthebricksprefiredat1600℃,duetothethermalexpansionmismatcheffect.Compromisingtheoverallproperties,theoptimalZrO2contentforsuchmagnesiabasedunfiredbrickissuggestedtobe4%.

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简介：采用溶胶-凝胶法，以硝酸铁（Fe（NO3）3·9H2O）和钛酸丁酯（Ti（OBu）4）为原料制备出均匀透明的TiO2-Fe2O3复合异质结构光催化薄膜材料，并将其在不同温度下进行了热处理。利用原子力显微镜（AFM）、紫外-可见分光光度计对试样的表面形貌和透光率进行了表征。考察了不同组成、热处理制度和温度对材料光催化性能的影响，特别是对可见光区的光催化性能的影响，并对其光催化机理进行了探讨。结果表明：TiO2-Fe2O3复合异质结构光催化薄膜的光催化活性比纯TiO2结构薄膜有了明显提高．且向可见光波段偏移。

简介：Thisworkinvestigatedthethermo-gravimetric(TG)changeandexplosionresistanceofultra-lowcementAl2O3-SiO2castablesaddedwith0,5%,10%,15%and20%of≤74μmrawbauxitepowderscontaining72.8%Al2O3,respectively.Thecastableswerepreparedusingwhitefusedaluminaasaggregate,powdersofwhitefusedalumina,fusedmullite,α-Al2O3ultrafines,3%CAcementand5%microsilicaasthematrixportion.TGchangeofthecastableswasinvestigatedbyathermo-gravimetricanalyzerforlargesizespecimen.Whentherawbauxiteadditionislessthan10%,themass-losingbehaviorofthecastablesissimilartothatwithoutrawbauxite,tendingtoreachaconstantmassaround400℃,beforewhichthemass-lossismildandproducinglittledestructiveinfluence.Withmorethan10%rawbauxiteaddition,however,themass-lossincreasessignificantly,andthetemperaturetoreachaconstantmassincreasesto600℃orhigher,unfavorabletostructuralstabilization.Withtherawbauxiteadditionupto20%,nonegativeinfluenceonexplosionresistanceisfound.