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1、伶水赫水工程姓名学号班级给水排水工程专业英语一、BasicFactorsinWaterAnalysisColour1Colourisduetothepresenceofcolloidalorganicmatterinsolutionorinsuspension.Thereisnorelationbetweenthecolourandthequantityoforganicmatter,asthelattermaybecolouredornot.2Waterwhichiscolouredisunpleasantwhenusedfordomesticpurposes,a
2、ndparticularlyfordrinking,aditalwaysgivesrisetodoubtsregardingitsportability.Certainindustriesrequirewatertobequitefreefromcolourwhichmightaffecttheproductsmanufacturedanddetractfromtheirquality;examplesarethepaper,rayon,cellulose,starch,anddyeingindustries.Colourremovaliseffectedbycoa
3、gulation.OdourandTasteOdoursandtastesaregenerallycausedbythepresenceofsecretionsintroducedintothewaterbyorganismswhichliveinthewater,suchasalgaeandfungi，etc.Certainchemicalproductsinsmallquantitiesalsogiveoffunpleasantodours・Thisisthecasewithphenolswhich,whencombinedwithchlorine,formth
4、everymalodorouschlorophenols.Unpleasanttastesarenotconsideredtobeimportantfromthehealthpointofview,buttheyareextremelyobjectionableindrinkingwater.Unpleasanttastesarecombatedbybreak-pointchlorination,byactivatedcarbon,bychlorinedioxide,andbyozone・Allwatersamples,fromwhateversource,have
5、theirownparticulartasterduetothesaltsandgasesdissolvedinthem.ThrbidityTurbiditygivesanideaofthecontentofmatterinsuspension.Theturbiditymaybeexpressedintermsofsilicabycomparingitstransparencywithanartificialsuspensionofsilica.Itexpressestheconcentrationoffinelydividedsuspendedmatterwhic
6、hmayeventuallysettleafervariableperiodsoftime,suchsubstancesbeingclay,finesand,limestoneparticles,elc.Themeasurementofturbiditybydropsofmasticisparticularlyusefulinascertainingthecontentofthecolloidcilparticleswhichwillnotsettleandwhichcannotbefiltered・Thatiswhyitisessentialtocarryoutt
7、histestafterfilteringtheliquidthroughpaperinordertoeliminatetheinfluenceoflargeparticles,andthustoknowexactlytheextentoftheturbidityduetothecolloidalsubstanceswhicharethemostfrequentcausesofcolour.Turbidityisalwaysunpleasantindrinkingwater.Waterscontainingsuspendedmatterwhichmayevent
