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Paper--MorethanMeetstheEyeA）Wearesurroundedbysomuchpaperandcardthatitiseasytoforgetjusthowcomplexitis.Therearemanyvarietiesandgradesofpapermaterials，andwhilstitisfairlyeasytospotthevarieties，itisfarmoredifficulttospotthegrades.B）Itneedstobeunderstoodthatmostpaperandcardismanufacturedforaspecificpurpose，sothatwhilstthecorn-flakepacketmaylooksmart，itisclearlynotsomethingdestinedforthearchives.Itismadetolookgood，butonlyneedsalimitedlifespan.Itisalsomuchcheapertomanufacturethanhighgradecard.C）Papercanbemadefromanalmostendlessvarietyofcellulose-basedmaterialwhichwillincludemanywoods，cottonsandgrassesorwhichpapyrusisanexampleandfromwherewegetthewordpaper.Manyoftheseareveryspecialized，butthepreponderanceofpapermakinghasbeenfromsoftwoodandcottonorrags，withthebulkbeingwood-based.PaperfromWoodD）Inordertomakewoodintopaperitneedstobebrokendownintofinestrands.Firstlybypowerfulmachineryandthenboiledwithstrongalkaliessuchascausticsoda，untilafinepulpofcellulosefibersisproduced.Itisfromthispulpthatthefinalproductismade，relyingonthebondingtogetherofthecelluloseintolayers.That，inaverysmallnutshell，istheessenceofpapermakingfromwood.However，therealityisrathermorecomplicated.Inordertogiveusourwhitepaperandcard，themakerswilladdbleachandothermaterialssuchaschinaclayandadditionalchemicals.E）Afurtherproblemwithwoodisthatitcontainsamaterialthatisnotcellulose.Somethingcalledlignin.Thisisessentialforthetreesinceitholdsthecellulosefibrestogether，butifitisincorporatedintothemanufacturedpaperitpresentsarchivistswithaproblem.Lignineventuallybreaksdownandreleasesacidproductsintothepaper.Thiswillweakenthebondbetweenthecellulosefibersandthepaperwillbecomebrittleandlookratherbrownandcareworn.Wehaveallseenthisinoldnewspapersandcheappaperbackbooks.Ithasbeenestimatedthatmostpaperbackbookswillhavealifeofnotgreaterthanfiftyyears.Notwhatweneedforourarchives.F）Sincethelignincanberemovedfromthepaperpulpduringmanufacture，theobviousquestioniswhyisitleftinthepaper?Theanswerliesinthefactthatligninmakesupaconsiderablepartofthetree.Byleavingthelignininthepulpapapermakercanincreasehispaperyieldfromatreetosome95%.Removingitmeansayieldofonly35%.Itisclearlyuneconomictoremovetheligninformanypaperandcardapplications.G）Italsomeans，ofcourse，thatlignin-freepaperisgoingtobemoreexpensive，butthatisneverthelesswhatthearchivistmustlookforinhissupplies.Thereisnopointwhatsoeverincarefullyplacingourvaluableartifactsinpaperorcardthatisgoingtohastentheirdemise.Acidisparticularlyharmfultophotographicmaterials，causingthemtofadeandissomecasessimplyvanish！H）So，howdowetellapieceofsuitablepaperorcardfromonethatisunsuitable?Youcannotdoitbysimplylooking，andratherdisappointingly，youcannotalwaysrelyonthelabel.Acid-freemightbetrueinasmuchasatestonthepapermayindicatethatitisaneutralmaterialatthistime.Butlignincantakeyearsbeforeitstartstheinevitableprocessofbreakingdown，andintherightconditionsitwillspeedupenormously.I）Addedtothis，asIhaveindicatedearlier，papermayalsocontainothermaterialsaddedduringmanufacturesuchasbleach，chinaclay，chemicalwhitenersandsize.Thislookslikeableakpicture，anditwouldbebutforthefactthattherearesupplierswhowillguaranteethematerialthattheysell.Ifyouwanttobeabsolutelysurethatyouarestoringin，orprintingon，thecorrectmaterialthenthisisprobablytheonlyway.J）Incidentally，acidscanmigratefrommaterialtomaterial.Liningoldshoeboxeswithgoodqualityacid-freepaperwilldolittletoguardthecontents.Theacidwillgetthereintheend.PaperfromRagK）Paperisalsocommonlymadefromcottonandragwaste.Thishastheadvantageofbeinglignin-free，butbecausethereismuchlesscottonandragthantrees，italsotendstobemuchmoreexpensivethanwoodpulppaper.Youwillstillneedtopurchasefromareliablesourcethough，sinceevenragpaperandcardcancontainundesirableadditives.L）Areliablesourceforqualityragpapersisarecognizedartstockiest.Manywatercolorartistsinsistonusingonlyfinequalityragpaperandboard.M）Themainlessontolearnfromthisinformationisthatyoucannotrelyonpurchasingarchivalmaterialsfromthehighstreet.Theonlysafesolutionistopurchasefromspecialistsuppliers.Itmaycostrathermore，butintheendyouwillknowthatyourimportantandvaluabledataandimageshavethebesthomepossible.1.Thecorn-flakepacketischeaperthanhighgradecard.2.Therearealotofmaterialswhichcanbeusedformakingpaper，butthesuperiorityonesaresoftwood，cottonandrags.3.Duringthewholemanufacturingprocess，thefinalproductismadefromapulpofcellulosefibres.4.Inordertomakewhitepaperandcard，themakerswilladdbleach.5.Liguinisessentialforthetreebutitwillmakepapereasytobreak.6.Manypaperproducerswillpreserveligninduringmanufacture，becauseleavingtheligninwillmakemorepaperfromatree.7.Acidisparticularlyharmfultophotographicmaterials.8.Iftheligninisremovedfromthepaper，thepaperwillbemoreexpensive.9.Althoughfreeoflignin，papermadefromcottonandragwastecanalsocostmoremoneythanwoodpulppaperbecausethereismuchlesscottonandragthantrees.10.WhatwecanlearnfromPaperfromRagisthatyouhadbetterbuyarchivalmaterialsfromspecialistsuppliers.文章精要本文主要介绍了我们平常所见所用的纸的复杂性，通过介绍用木头和破布料造纸的过程，使我们对纸的类别、属性有了更深入的了解。1.B根据题干中的信息提示词corn—flakepacket，hig