简介:DimerizationConstantDeterminationof6-O-Benzoyl-β-CyclodextrininAqueousSolution.DimerizationConstantDeterminationof6-O-Benzoyl?..
简介:GypsumcrystallizationalongwiththesimultaneousregenerationofKClwasinvestigatedbythereactionofCaCl2solutionwithK2SO4.WelldevelopedsheetstructuregypsumcrystalswereproducedwhenK2SO4solutionwasaddedintotheCaCl2solutionbyslowtitrationorinmultiplestagesover2-8hfollowedby2hequilibration.InordertoregenerateKClsolutionasconcentratedaspossible,K2SO4solidwasaddedintothegivenCaCl2solutioninsteadofK2SO4solution,obtaininggypsumcrystalswithalmostthesamequalitybymultistageadditionwith[SO42-]/[Ca2+]molarrationolargerthan0.8.However,impurityofK2SO4·CaSO4·H2OwasdetectedbyXRDandwasfurtherconfirmedbySEM-EDSintheproducedcrystalswhenthe[SO42-]/[Ca2+]ratioincreasedto1.1.ItisprovedthatappearanceofthedoublesulfateisattributedtotherelativelyhighconcentrationofK2SO4.So,itisessentialtoproperlycontrolthe[SO42-]/[Ca2+]ratioandmakesure[Ca2+]inexcesstosuppressthesolubilityofCaSO4evenattheexpenseoflowcalciumremovalrate.
简介:Piracy,asanage-oldcriminalactivity,usedtobeanimportantforceaffectingworldpolitics.Reportsofpirateattacksweredecliningworldwidesincethenewcentury.Howeverpiracyhasbeenquiterampantsince2007.EspeciallyintheSomaliwaters,pirateshaveconductedsavaginglootingsintheirincreasinglyfrequentraids,causingimmenseharmsrarelyseensinceWorldWarⅡ.Undersuchcircumstances,itisimperativetoreviewtheissueofpiracy,whichisanancientaswellasacurrentproblemforus.
简介:PolygonalobjectisafundamentaltypeofgeometricdatainvectorGIS.Thekeystepofcleaningtopologicalrelationshipafterdatacollectionofpolygonallayeristobuildpolygonalobjectsfromdigitalarcs.Therawdigitalarcsmayintersectwitheachother.Thealgorithmforbuildingpolygonalobjectsaftertherawarcshavebeensplitatallintersectionsispresented.Thebuild-upofpolygonalobjectsinthispaperisdesignedtobeimplementedbytwosteps.Thefirststepistoextractallthepolygonsneededforbuild-upofpolygonalobjectsfromarcs.Thesecondstepistoorganizepolygonalobjectsfromthesepolygons.Forthefirststep,atracingalgorithmisproposed.Thealgorithmmerelyextractsthepolygonsneededforthebuild-upofpolygonalobjects,whichisasubsetofallthepossiblepolygonsthatcanbeinducedfromthearcs.Forthesecondstep,analgorithmbasedonaspeciallydesignedorderofpolygonsisadvanced.Allthetopologicalrelationshipsamongthepolygonsaresho
简介:Inthispaper,anewmethodfordealingwithsubstructurechainispresented.Here,asubstructurechainmeansastructureconsistingofanumberofidenticalsubstructuresconnectedinseries.Thismethodisparalleltotheexpansionmethodinthestructuralanalysisaccordingtothetransversesection.Themethodofshiftinvarianceandthatofinitialparameterandtransfermatrix,theirmutual-relationandcom-bineduse,aswellastheanalysisoftheeigenproblemonthetransversesection,andtheexpansionmethodbasedontheeigenvectorsaredescribedinthispaper.
简介:Totacklefoodshortages,theDPRKshouldimplementanexport-orientedstrategyofeconomicdevelopment,pushforwarddomesticreformandopenuptotheoutsideworld,aswellasimproveitsexternalposition.Modernizationofagricultureshouldbesustainedbythedevelopmentofsecondaryindustriesandmodernservicesthatincreasefoodimports.