制浆造纸专业单词6.doc

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1、1.1SIGNIFICANCEOFPAPERThesignificanceofpaperandpaperproductsinmodernlifeisobvioustoeveryone:nomanufacturedproductplaysamoremeaningfulroleineveryareaofhumanactivity.Paperprovidesthemeansofrecording,storageanddisseminationofinformation;virtuallyallwritingandpr

2、intingisdoneonpaper.Itisthemostwidelyusedwrappingandpackagingmaterial,andisimportantforstructuralapplications.Theusesandapplicationsforpaperandpaperproductsarevirtuallylimitless.Newspecialtyproductsarecontinuallybeingdeveloped・Atthesametime,theindustryisawar

3、eofinroadsandcompctitionfromothersectors,notablyplasticsandelectronicmediaformarketstraditionallyservedbypaper.Asneverbefore,newtechnologyandmethodologyisbeingadoptedsothattheindustrycanrcmaincompetitiveinexistingmarketsandbereceptivetonewopportunities・Aside

4、fromtheoutputofproductsandservices,thePulpandPaperIndustryprovidesemploymentforvastnumbersofpeopleandplaysavitalroleintheoveralleconomyofthesedays・1.2DEFINITIONSOFPULP,PAPERANDPAPERBOARDPaperhastraditionallybeendefinedas"afeltedsheetformedonafinescreenfromaw

5、atersuspensionoffibers".Currentpaperproductsgenerallyconformtothisdefinitionexceptthatmostproductsalsocontainnon・fibrousadditives.DiyformingmethodsarcnowutilizedforthemanufactureofafewspecialtypaperpIntroductionpapermaking・Pulpfibersareusuallyofvegetableorig

6、in,butanimal,mineralorsyntheticfibersmaybeusedforspecialapplications・Pulpsusedforchemicalconversionintonon-pape『productsarecalleddissolvingpulps.Thedistinctionbetweenpaperandpaperboardisbasedonproductthickness.Nominally,allsheetsabove0.3mmthicknessareclassed

7、aspaperboard;butenoughexceptionsareappliedtomakethedistinctionsomewhathazy・1.3CHRONOLOGYOFTECHNOLOGICALDEVELOPMENTPaperderivesitsnamefromthereedyplant,papyrus・TheancientEgyptiansproducedtheworldsfirstwritingmaterialbybeatingandpressingtogetherthinlayersofthe

8、plantstem(seeFigure1-1)・However,completedefiberingwhichischaracteristicoftruepapermakingwasabsent.ThefirstauthenticpapermakingoriginatedinChinaasearlyas100AD,utilizingasuspensionofbambooormulber