Selecta PH-3005 - Page 30

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 Afterremovingtheelectrodeprotectioncap,thesensitiveglassbubbleoftheelectrodeshouldbeavoidedfrom
contactingwithhardobjects.Anydamageorscratchingwillmaketheelectrodeineffective.
 Afterthemeasurement,theelectrode protection cap should becovered in time. A small amount of external
referencesupplementshouldbeplacedintheprotectioncaptokeeptheelectrodebulbmoist.Donotimmerse
theelectrodeindistilledwaterforalongtime.
 TheQ9short‐circuitplugoftheelectrodeshouldbekeptcleananddrytopreventshort‐circuitbyrust,otherwise
itwillcausemeasurementinaccuracyorfailure.
 Electrodesshouldavoidlong‐termimmersioninproteinsolutions andacidicfluoridesolutions,andshouldavoid
contactwithsiliconeoil.
 Duetothedifferentelectrodematerials,pleaseselecttheappropriateelectrodeaccordingtotheactualuseto
avoiddamagetotheelectrode.
 RepairpHElectrodes:Afterlong‐termuseoftheelectrode,iftheslopedecreasesslightly,thebottomendofthe
electrodecanbeimmersedin4%HF(hydrofluoricacid)for(3‐5)s,washwithdistilledwater,andthensoakin0.1
mol/Lhydrochloricacidsolutiontorejuvenate.
 CleanpHElectrode:Ifthemeasuredsolutioncontainssubstancesthatareeasytocontaminatethesensitivebulb
orblocktheliquidjunctionandmaketheelectrodepassivated,theslopewilldecreaseandthedisplayreadingwill
beinaccurate.Ifthisphenomenonoccurs,accordingtothenatureofthecontaminant,theelectrodeshouldbe
cleanedwithanappropriatesolutiontoregeneratetheelectrode.
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Table6‐1Referencetableofelectrodecontaminantsandcleaningagents
Contaminant Detergent
Inorganicmetaloxide Lessthan1mole/Lofdiluteacid
Organicfattysubstances Dilutedetergent(weakalkaline)
Resinpolymermaterial Alcohol,acetone,ether
Proteinhaemocyteprecipitate 5%pepsin+0.1mol/LHClsolution
Pigmentsubstance Dilutebleachsolution,hydrogenperoxide
Formoredetails,seepHelectrodeinstructions.
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