简介：Silicaaggregateswerepreparedbybase-catalyzedhydrolysisandcondensationofalkoxidesinalcohol.Polyethyleneglycol(PEG)wasusedasorganicmodifier.ThesolswerecharacterizedusingSmallAngleX-rayScattering(SAXS)withsynchrotronradiationasX-raysource.Thestructureevolutionduringthesol-gelprocesswasdeterminedanddescribedintermsofthefractalgeometry.As-producedsilicaaggregateswerefoundtobemassfractals.Thefractldimensionsspannedtheregime2.1-2.6correspondingtomorebranchedandcompactstructures.BothRLCAandEdenmodelsdominatedthekineticgrowthunderbase-catalyzedcondition.

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简介：ThispaperreviewsthehistoryofdevelopmentandproductionofsilicabricksatLuoyangRefrac-tories(Group)Co.,Ltd,(FormerLuoyangRefrac-toriesFactory).Throughtheimprovementandin-troducingtechnologyfromabroadthecompany'smanagementandqualitystandardonsilicabricksproductionhasreachedahigherlevel.Thephysicalandchemicalspecifications,aswellastheappear-anceofsilicabricksforcokeovens,hotblaststovesandglasskilnshavereachedtheadvancedinterna-tionallevel.NowthecompanyhasbecomeproducingbaseandmainexportingbasevariouskindsofsilicabricksinChina.

简介：TheannualoutputofChina'ssilicabrickamountsuptoover300thousandtons,whichaccountsformorethan70%ofthetotaloutputofsilicabricksintheworld.Besidessatisfyingdomesticmarkets,China'ssilicabrickshavebeenexportedtomanycountriesandregionssuchasJapan,USAetc.Inthispaper,thesituationofsilicabricksproduction,technology,salesandexportinghavebeendescribed.Alsosuggestionsonimprovementofsilicabricksqualityandexporting,corporationwithforeignpartnershavebeenputforwardinordertowinlargermarketsharebothathomeandabroad.

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简介：SmallX-rayScattering(SAXS)experimentusingSynchrotronRadiationasX-raysourcewasusedtodeterminetheaveragewallthicknessofmesoporoussilicaprepardbycondensationoftetraethylorthosilicate(TEOS)usingnon-ionicalkylpolyethyleneoxide(AEO9)surfactantastemplates.Theresultsagreedwiththatofhigh-resolutionTEM(HRTEM)measurement.

简介：Dreippingelectrolytesintosilicasol,gellingreactionwilloccur,Theresearchindicates:thisisacomplicatedphysicemistrycourse,whichconsistsofapre-reactionandapolymerizaion,Theformercontrolsthewholecourse,andinwhichelectroniclayersofthesol'sparticlesbe-comemoreandmorethiner,butwithincresingofthesolconcentration,itscontrolforcewillbediminished,tillthefast-coagulation,thegellingcousebecomeso-controlled,Thelatterisanin-finitepolymericchani-reaction.Theresultofgelatinationistoproduceaverybigplymericmolecule-gel,whichinvolvesinallspace,includesallwater,anditsmolecularweightisin-definitebig.Theresearhalsoindicates:thedy-namiccourseofthegellingcouldbedescribedquantitaivelybyanexperienceformula:lgt=-nlgc+B,Allofthecharacteristicvalueshavedefinitephysicalmeaning,Electronicvalueofthecontrary-inosisthebiggestinfluentialfactor,thenaturesofthecontrary-ionsandthenaturesofthesame-electronic-inoshaveafewinfluentialforcesonthecharacteristicvalues,Thetemperatureincreasingmakesthegellingreactionfast.

简介：Whenasilicaopticalfiberisusedfortransmittingultraviolet(UV)light,theproblemsassociatedwiththedamageandtransmissiondeteriorationofsilicafiberintheUVregionneedtobesolvedinthefabricationprocess.Inthispaper,animprovedsilicafiberfabricationprocesswaspresentedtoenhanceUVtransmission,whichcombinedtheUVpre-irradiationonhigh-OHconcentrationpreformwithheattreatmentwhiledrawingfiber.Theimpactofthestructuraldefectsandcolorcenterswasdiminishedgreatlybythenewmethodoffabrication.Theexperimentalresultsaccordedwiththetheoreticalanalysis,andtransmissionwasimprovedabout0.4-0.7dB/mforwavelengthfrom350to400nm.

简介：Asmall-anglex-rayscattering(SAXS)techniqueusingsynchrotronradiationasthex-raysourcehasbeenemployedtocharacterizethemicrostructureofmesoporoussilicapreparedbyone-pottemplate-directedsynthesismethodology.ThescatteringofpuresilicaagreedwithPorod’slaw.thescatteringoforganomodifiedmesoporoussilicashowedanegativedeviationfromPorod’slaw,suggestingthataninterfaciallayerexistsbetweentheporesandsilicamatrix.Itwastheorganicgroupscomprisingtheinterface,asshownby^29Sicross-polarizationmagic-anglespinningnuclearmagneticresonanceimaging(^29SicpMAS/NMR)andFouriertransforminfraredspectroscopy(FTIR),thatcausedthisnegativedeviationofSAXSintensityfromPorod’slaw,andtheaveragethichnessoftheinterfaciallayercouldbededucedfromthisnegativedeviation.Copyright2001johnWileyandSons,Ltd.

简介：Ascokeovenbecominglarger,silicabrickforcokeovenisrequiredtobeofhighuqality,LuoyangRefractories(Grop)Co.Ltd.(LRCO)hasre-searchedthemineralizerwhichcontainsCa^2+,R^+,Al^3+,F^-,emphaticallyandproposedtheprincipleofcompositemineralizerbasdonthepropertiesofrawmaterialsused.Highperformancesiliabrickwhichischaracterizedbylowthermalexpansionrate,goodhightemperatureproperties,residualquartz<0.5%,truedensity2.31,andhighbulkdensitysilicabrickforcarbonizationroomwithapparentporosity13%,bulkdensityl.96g/cm^3havebeendevelopedandproducedsuccessfullybyLR-CO.Thequalityofthebrickshasreachedtheinter-nationaladvencedlevel.

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简介：Ricehuskwasusedtopreparethesilicaofamorphousnaturebeingseveraltimesmorereactivethanthatobtainedfromthemineralkingdom.Numberofricehuskbatcheswerepyroprocessedundervaryingtime-temperatureparametersforthispurpose.Theashresultingfromabatchpyroprocessedat500℃for8hcontained92.01%silica.Itwasupgradedto98.50%byapplyingphysicochemicalpurificationprocedures.Themineral,wollastonite(CaSiO3),wassynthesizedfromthuspreparedsilicaandlimestonecontaining55.91%CaO.Solidstatereaction,betweenCaOandSiO2wasattemptedatdifferenttemperaturesinthepresenceofamineralizer.Thesinteringtemperature,foraffectingthesaidsynthesis,wasrangedbetween900℃to1300℃withthestepsof100℃.SpecificchemicalanalysistechniqueswereappliedtodeterminetheeffectivenessofcarriedoutreactionandpromisingbatchesweresubsequentlysubjectedtoXRDinvestigations.Theproducedmineralwasalsocharacterizedregardingitsphysicalpropertieslike:colour,hardness,meltingpointandspecificgravity.Percentyieldoftheproducedwollastonitewasalsoestimatedandcomparedwiththatofobtainedbyotherresearcherswhosynthesizeditbyusingsilicafrommineralkingdom.Batchessinteredat1200℃and1300℃for1hshowedtheoverallbestresults.

简介：与TEM和物理煤气的吸附技术，多孔的性质ofnano纤维状的硅石(MLD：92.73%)从天赋，纤蛇纹石在这篇论文被学习。Theresults显示那多孔的nano纤维状的硅石源于naturechrysotile的八面的表完全溶解了的水镁石和有四面的表由酸的沥滤折叠的Si-O。它的长度在微米或纳米规模。有毛孔的二种类型：在附近的纤维之中的毛孔和在nanofiber的毛孔。这些毛孔(在直径的不到6.5nm，主要2.1nm和3.8nm)都属于中央毛孔。在纤维的毛孔在SiO_2粒子之中由那些组成，那些在总数，残余nanotubes和毛状的试管之中。Nano纤维状的硅石作为catalyzer和填料的一个搬运人证明比传统的硅石好为增强橡胶和塑料。

简介：Electrochemicalandcorrosionbehaviourofreinforcedsteelembeddedincementpastesincorporatingdifferentamountsofsilicafumeasapartialreplacementofcementhasbeenstudiedinchlorideandsulphatesolutionsbyusingdifferentelectrochemicaltechniques.Theresultsindicatethat,whilesteelpassivitydegreeislowinthecontrolsamples'uponsoakinginthecorrosivemedia,ithasbeenhighihsamplesincorporatingsilicafumeandincreasedwithincreasingsilicafumecontent.Theimprovementeffectofsilicafumemaybeattributedtotheporesolutionstructureofthecementpaste,whichlimitsthemobilityofaggressiveionsnearthesurfaceofthesteel.Themechanismofsteelcorrosionduetochlorideandsulphateattackandpassivationeffectofsilicafumearediscussed.

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简介：SmallangleX-rayscatteringexperimentshavebeenperformedtostudythemicrostructureofmessoporoussilicameterialspreparedbycondensationoftetraethylorthosilicateusingnonionicalkylpolyethyleneoxide(AEO9)andioniccetyltrimethylammoniumbromide(CTAB)surfactantastemplates.Itistheporeswithinthenanometrerangethatproducethemaincattering.ThescatteringofthepuresilicasystemsobeyPorod’slaw.Thismaybebecausethetemplatesproducesomeadditionalscatteringbackgroundandthenmakethescatteringofporesdistorted.TheresultsshowthatthefullremovaloftemplatesfromtheporesofthematerialsbySoxhletextractionisveryeasyforAEO9,butitisdifficultforCTAB.Thepositivedeviationcorrectionisalsoperfromed.

简介：Silica-bound15-Crown-5,18-Crown-6withaspacerofpropyloxymethylandtheirplatinumcomplexeshavebeensynthesized.Itwasfoundthattheywereefficientcatalystsforthehydrosilylationofolefmswithtriethoxysilaneinthetemperaturerangeof60to130℃.

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