2013年12月六级新题型、段落匹配

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1、Paper--MorethanMeetstheEye　　A）Wearesurroundedbysomuchpaperandcardthatitiseasytoforgetjusthowcomplexitis.Therearemanyvarietiesandgradesofpapermaterials，andwhilstitisfairlyeasytospotthevarieties，itisfarmoredifficulttospotthegrades.　　B）Itneedstobeunderstoodthatmostpaperandcardisma

2、nufacturedforaspecificpurpose，sothatwhilstthecorn-flakepacketmaylooksmart，itisclearlynotsomethingdestinedforthearchives.Itismadetolookgood，butonlyneedsalimitedlifespan.Itisalsomuchcheapertomanufacturethanhighgradecard.　　C）Papercanbemadefromanalmostendlessvarietyofcellulose-base

3、dmaterialwhichwillincludemanywoods，cottonsandgrassesorwhichpapyrusisanexampleandfromwherewegettheword"paper".Manyoftheseareveryspecialized，butthepreponderanceofpapermakinghasbeenfromsoftwoodandcottonorrags，withthebulkbeingwood-based.　　PaperfromWood　　D）Inordertomakewoodintopaper

4、itneedstobebrokendownintofinestrands.Firstlybypowerfulmachineryandthenboiledwithstrongalkaliessuchascausticsoda，untilafinepulpofcellulosefibersisproduced.Itisfromthispulpthatthefinalproductismade，relyingonthebondingtogetherofthecelluloseintolayers.That，inaverysmallnutshell，isth

5、eessenceofpapermakingfromwood.However，therealityisrathermorecomplicated.Inordertogiveusourwhitepaperandcard，themakerswilladdbleachandothermaterialssuchaschinaclayandadditionalchemicals.E）Afurtherproblemwithwoodisthatitcontainsamaterialthatisnotcellulose.Somethingcalledlignin.Th

6、isisessentialforthetreesinceitholdsthecellulosefibrestogether，butifitisincorporatedintothemanufacturedpaperitpresentsarchivistswithaproblem.Lignineventuallybreaksdownandreleasesacidproductsintothepaper.Thiswillweakenthebondbetweenthecellulosefibersandthepaperwillbecomebrittlean

7、dlookratherbrownandcareworn.Wehaveallseenthisinoldnewspapersandcheappaperbackbooks.Ithasbeenestimatedthatmostpaperbackbookswillhavealifeofnotgreaterthanfiftyyears.Notwhatweneedforourarchives.F）Sincethelignincanberemovedfromthepaperpulpduringmanufacture，theobviousquestionis"whyi

8、sitleftinthepaper?"Theanswerliesinthefactthatligninmak