Designation:E1772–95(Reapproved2001)StandardTestMethodforParticleSizeDistributionofChromatographyMediabyElectricSensingZoneTechnique1ThisstandardisissuedunderthefixeddesignationE1772;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodisvaluableforthemeasurementofparticlesizeandcoversdeterminationoftheparticlesizedistributionofchromatographymediaintheoverallsizerangeofapproximately1to450µmusingtheelectricsensingzone(ESZ)apparatus.Thisinstrumentusesanelectriccurrentpathofsmalldimensionsthatismodulatedbyindividualparticlepassagethroughanapertureandproducesindividualpulsesofamplitudeproportionaltotheparticlevolume(1).21.2ThevaluesstatedinSIunitsaretoberegardedasthestandard.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:D1193SpecificationforReagentWater3E177PracticeforUseoftheTermsPrecisionandBiasinASTMTestMethods4E456TerminologyRelatingtoQualityandStatistics42.2OtherDocument:Manufacturer’sOperatingManualforParticleSizeDistri-butionAnalyzer53.Terminology3.1Definitions:3.1.1equivalentvolumediameter—thediameterofaspherewithavolumeequaltothatoftheactualparticle.3.1.2volumeweighted(mass)mediandiameter—anumberdistribution,n(d),ismeasured,andN5(i51Cn(di)isthetotalnumberofparticlesintheCclassesandn(di)isthenumberofparticlesinclassi(correspondingtodiameterdi).3.1.2.1Discussion—Fromn(d),thecorrespondingvolumedistributioncanbecalculated:f~di!5n~di!p6di3/V5n~di!di3/(i51Cn~di!di3(1)where:V5p6(i51Cn~di!di3(2)isthetotalparticlevolume.Acumulativevolumedistribution,F(di),isdefinedbyF~di!5(xi#dif~xi!(3)Thevolumeweighted(mass)...
