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1、TheeticalInvestigationsofRegularitiesofBindingPropertiesAvailabilityfOxideCompoundsofSpecialCementsViktiiaTaranenkovaDepartmentofTechnologyofCeramicsRefractiesGlassEnamelsNationalTechnicalUniversity“KharkovPolytechnicIns

2、titute”21FrunzeSt.Kharkov61002UkraineAbstractOxidecompoundsareincludedinalltypesofcementswhichtobemostimptantinpractice.Thatiswhyagreatattentionispaidtostudyingthefeaturesdeterminingtheavailabilityofbindingpropertiesfmen

3、tionedcompoundswhenonesinteractwithwater.Despitenumerousstudiestherearenotyetcleartheeticalcriteriatoevaluatethebehaviofvariousoxidecompounds(ifonlyqualitativelynottomentionquantifiably)concerningthepossibilityoftheiruse

4、inthechemistryofspecialcements.Tobringouttheregularitiesofbindingpropertiesavailabilityitisnecessaryfirstofalltoevaluatethereactivityofcementcompoundsinregardtowater.Ftheprobleminviewtosolvetheconceptofelectronegativitie

5、shasbeenproposedbyS.S.Batsanov.ThengiventheywasdevelopedbyN.F.Fedov.UsingtheproposedmethodFedovhascalculatedelectronegativitiesofcompounds(ENcomp.)suchascalciumsilicatesaluminateswhosebindingpropertiesareknown.Valuesofco

6、mpoundelectronegativitieswerecalculatedinaccdancewithSerson’stechniqueasageometricmeanofelectronegativitiesoftheelementsmakingupthecompound.Acomparisonofthevaluesofrelativecompoundelectronegativity(ENrel.)obtainedbydivid

7、ingENcomp.onthewaterelectronegativity(ENн2о)withtheavailabilityofbindingpropertiesallowedtosuggestthatbindingpropertiesareavailableonlyinacertainrangeofENrel..HoweveranalyzingtheresultsofcalculationsfulfilledbyFedovnumer

8、ousinaccuracieswhichrequirecrectionhavebeenrevealedasaconsequencetheENcomp.valuesaswellrangeofENrel.wherebindingpropertiesoccurmustberevised.Meovercompoundsdiscoveredinrecentyearsasbeingtheanaloguesofcalciumsilicatesalum

9、inateswerenotconsidered.Fexamplegermanatesgallatesofalkalineearthelementswhichareofagreatinterestfchemistryofspecialbinders.TakingintoconsiderationallmentionedabovetheENcomp.valuesfmethan150silicatesgermanatesaluminatesg

10、allatesferritesalumoferritestitanatesstannatesplumbatesofalkalineearthelementshavebeencalculatedbyusingtheelectronegativityconcept.AsaresultofourinvestigationstherangeofENrel.wherecompoundsoccurbindingpropertieshasbeende

11、termined.Besidesdataobtainedwillallowtothemostfavableconditionsfcompoundhardening.Thusintermsofourdatathebindingpropertiesavailabilityfoxidecompoundsprospectsoftheirapplicationinspecialcementtechnologycanbeevaluated.igin

12、alityTopurposefullysynthesizespecialmultimineralcementsitisnecessarytohaveinfmationconcerningbindingpropertiesofindividualphasesbeingpartofgivencements.Fromthispointofviewthemostpromisingwayfcreationofnewbindingmaterials

13、shouldbedirectedonstudyingnotonlydinarybindersbutalsotheiranalogues.Inparticularinvestigationsmustbecurriedoutinconsiderationofgermanatesgallatesofalkalineearthelementswhichareacterizedwithacombinationoffollowingusefulpr

14、operties:refractinesshighdensitymechanicalstrengthetc.Nowadaysanumberofempiricalsemiempiricalgeneralizationsintermofconsiderableamountofexperimentaldataaremade.Onesallowtoevaluateapossibilityofuseofsomeoxidecompoundsinth

15、echemistryofspecialcements.Butgivengeneralizationsasarulehaveaqualitativeacter.Takingintoconsiderationallmentionedabovetheactualproblemofchemistryofbindingmaterialsisdevelopmentofquantitativedependencesaswellasrevealingt

16、hephysicalchemicalconditionsdeterminingthebindingpropertiesavailability.Asaresultofourinvestigationsitisshownthatbymeansofconceptofelectronegativitythecertainrangeofrelativeelectronegativitiesvalueswherecompoundsbeingcon

17、sideredhavebindingpropertiescanbedeterminedratherclearly.Itisertainedthatwithingivenrangeanumerousgroupofbinaryternarycompounds(about100)arepresentincludingthoseoneswhosebindingpropertiesarenotyetstudiedcompletely.Keywds

18、:acidbasepropertieselectronegativitybindingpropertiesspecialcements__________________________________________Crespondingauth:taranenkova@undernmalconditionshavebindingpropertiesatthehardeningunderraisedtemperaturescondit

19、ions(SychevM.M.1971).Takingintoconsiderationallmentionedabovetheactualproblemofchemistryofbindingmaterialsisdevelopmentofquantitativedependencesaswellasrevealingthephysicalchemicalconditionsdeterminingthebindingpropertie

20、savailability.2.ExperimentalBindersarecombinationoftwochemicalreagents–solidpowderliquidbindingpropertiesavailabilityresultsfromchemicalinteractionbetweenreagents.Tobringouttheregularitiesofbindingpropertiesavailabilityw

21、henpowderisoxidecompoundlikecalciumsilicatesliquidisawateritisnecessaryfirstofalltoevaluatethereactivityofcementcompoundsinregardtowater.Sincereactionsofcalciumsilicatestheiranalogueswithawaterareacidbaseinteractionsitis

22、obvioustheirratewillbedeterminedbyextentofdifferenceinacidbasepropertiesofstartingreagentsi.e.mineralcompoundswater(FedovN.F.1977).Traditionalchemicalmethodsfconsiderationacidbasepropertiesofsilicatestheiranaloguesarenot

23、applicablebecausegivencompoundsaredissolvedhardlyinthewater.MentionedfeaturedoesnotallowtoacterizetheiracidbasepropertiesbymeansofpHdetermination(BokijG.B.etal.1956).ToestimateacidbasepropertiesofsilicatesS.S.Batsanovhas

24、proposedtousethevaluesofcompoundelectronegativities(BatsanovS.S.1968).Conceptofelectronegativity(EN)isimptantnotonlyftheeticalchemistrybutalsomineralogysinceusingENdatatheregularitiesofachangeinpropertiesofmineralschemic

25、alcompoundscanbeexplained.FexampleduetoENdatatheestimationofchangeincolrefractiveindexofsubstanceswasgiven(PovarennyhA.S.1955).InthesamewkismentionedthatENvaluesarenotyetenoughusedfanalysisofnaturefmationofchemicalcompou

26、nds.Atomelectronegativityistheattractionenergybygivenatomtheelectronsatajointwithotheratomsi.e.ENisameasureofatomaffinityfelectronaccdingtoLewis’stheyonecanacterizeacidbasepropertiesofatom.SersonhasshownthatoxideENvalues

27、areinverselyproptionaltopHvaluesobtainedatwaterdissolutionofoxides(SersonK.1954).ThisfactallowedtoapplyENconceptionfstudyingthecompoundacidbaseproperties.ThenconceptofelectronegativitywasdevelopedbyN.F.Fedovwhichproposed

28、touseonefpredictionofbindingpropertiesavailabilityofoxidecompounds(FedovN.F.1972).UsingtheproposedmethodFedovhascalculatedelectronegativitiesofcompounds(ENcomp.)thekindofcalciumsilicatesaluminates(suchassilicatesstannate

29、splumbatestitanatesaluminatesofalkalialkalineearthelements)whosebindingpropertiesareknown.ValuesofcompoundelectronegativitieswerecalculatedinaccdancewithSerson’stechniqueasageometricmeanofelectronegativitiesoftheelements

30、makingupthecompound.Acomparisonofthevaluesofcompoundrelativeelectronegativity(ENrel.)obtainedbydividingENcomp.onthewaterelectronegativity(ENн2о)withtheavailabilityofbindingpropertiesallowedtosuggestthatbindingpropertiesw

31、ereavailableonlyinacertainrangeofENrel..DependingonENrel.valuesFedovhasclassifiedbeingstudiedcompoundsinto3groups:1)compoundsnotfmingcementstoneasaresultmuchtoointensiveinteractionwithawater2)compoundshavingbindingproper

32、ties3)compoundsnothardeningduetolowreactivityrelativetoawater.HoweveranalyzingtheresultsofcalculationsfulfilledbyFedovnumerousinaccuracieswhichrequirecrectionhavebeenrevealedasaconsequencetheENcomp.valuesaswellrangeofENr

33、el.wherebindingpropertiesoccurmustberevised.FexampleENн2оvaluecalculatedaccdingtoSerson’stechniqueisequalto40343whilecalculatingFedovusedvalue404.Besidescompoundsdiscoveredinrecentyearsasbeingtheanaloguesofcalciumsilicat

34、esaluminates(namelygermanatesgallatesofalkalineearthelementswhichareofagreatinterestfchemistryofspecialbinders)werenotconsidered.MeoverdataconcerningENfcomplexternaryoxidecompoundssuchimptantcompoundsfcementchemistryasfe

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