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ZZeolites719●ZZZ-value(orpolarityparameterZ)—isanindexoftheionizingpowerofasolventbasedonthefrequencyofthelongestwavelengthelectronicabsorptionmaximumof-ethyl--methoxycarbonylpyridiniumiodideinthesolvent.TheZ-valueisdefinedbyZ=.��λwhereZisinkcalmol−andλisinnm,respectively.Ref.:[i]MullerP()PureApplChem:WKZadracell—Electrolyticcellemployedin�electrowin-ningofgold.Thedesignisbasedonplacingintoaper-foratedcylindricalpolymercontainer:steelwoolas�cathode,afeedertube,anda�currentdistributor.The�anodeisastainlesssteelmeshoutsidethecon-tainer.Gold-richsolutionisfedatlowfeedratethroughthefeederatthebottomofthesteelwool-filledcompart-ment,goldisreductivelyextracted,andtheextractedso-lutionpassesthepolymercontainer.Refs.:[i]PletcherD,WalshFC()Industrialelectrochemistry.BlackieAcademic&Professional,London;[ii]ZadraJB,EngelAL,HeinenHJ()USBureauofMinesReportRHZambonipile—Thiswasa�drypileconsistingoftinfoilonpaperandlayersofmanganesedioxide.Thelatterwastransferredasapas