英文細胞分裂實驗報告5700字

英文細胞分裂實驗報告5700字

生物系實驗報告（Prohibitedforcommercialpurposes）姓名班級學(xué)號實驗日期科目實驗名稱thecellcycleandmitosis合作者指導(dǎo)教師成績LAB6:TheCellCycleandMitosisIntroduction:Mitosisisthemainprocessofcellularreproduction.Itcontainsinterphase,metaphase,anaphaseandtelophase;cytokinesisincluded.Twoidenticaldaughtercellswhichnearlypossessthesamegeneticmaterialsinparentcell.InterphaseisaphaseincludingG1,S,andG2,whichisnotpartofmitosis.ThechromosomalmaterialswhoseDNAhavebeenfixatedcanbedyedbyFeulgenstain.Accordingtotheroottipscellsweobserve,thedifferentmitoticstagescanbeeasilydistinguished.Inthislab,wecanobservedifferentstagesofmitosisinplantscells.Wewillmakeawetmountslideofgarlicroottips,sothatwecanlearntouseselectivestainingtechniques(onlystainDNAinchromosomes)-Feulgenstain.Materialsandmethods:Materials:Compoundmicroscope(NIKONECLIPSEE100),waterbath(at60℃),glacialaceticacid-methanolfixative(1:3),1Mhydrochloricacid,45%aceticacid,Feulgenstain,preparedslidesofonionroottip,lenstissue,garlicroottips,forceps,slides,coverslips.Methods:PartⅠ：①Observeapreparedslideofalongitudinalsectionofonionroottipwithmicroscope,fromlow-powertohigh-power.②Concentrateintheregionwheretheapicalmeristemoftheroot,andidentifycellsindifferentphases.③Lookat30-50onionroottipcells,thentallythefrequencyofmitoticphases.RecordthedataintableT-1.PartⅡ：Inordertoprepareawetmountslide..①Add4mloffreshlypreparedmethanol-aceticfixativeinavial,thendealwithabout2-3mmgarlicroottipsinitfor15minutesat60℃..②Havingfinishedfixative,slowlypouroffthefixativeintowastercontainer,thenadd2ml1Mhydrochloricacidtothevial..③Placethevialinthewaterbathfor10minutesat60℃,sothattheplantcellwallscanbe.④Pourofftheacid,add1mlFeulgenstainintothevial,maintainfor45-60minutesatroomtemperature..⑤Placeadropofaceticacidontheslide,andtransferaroottip(cutfromtherootofgarlic)toit,thencoverthesamplewithcoverslip..⑥D(zhuǎn)rytheslidewithtwopiecesofpapertowels,usethumbtopressdirectlydownwardoverthecoverslip.Becarefultopreventthecellsfromrollingandoverlapping..⑦Observetheslidewithlowpowertolocatethepinkregionofchromosomeswhichisstained.Reducethelightintensitytoseethedetailsofcellsandchromosomes..⑧Studytheslideandidentifythecellsindifferentmitoticphases.Lookat30-50dividinggarlicroottipcellsandcalculatethefrequencyofthephases,thenrecordthedataintableT-2.Results:PartⅠ:AswecanseeinaseriesofFigures1-1andtableT-1,someregionsofrootarecomposedofnormalcellsandtheareathatcontainsmanycellsofmitoticphaseistheapicalmeristem.79.6%ofcellsareininterphasewhilethereare20.4%ofcellsinmitoticphase,andoverviewthecellswhichareintelophase;wecanseetheunclearcellplate.Cellplatecanfinallygrowtocellwallwhichcompletelyseparatesthetwodaughtercells.PartⅡ:AccordingtoFigure2-1,2-2,andtableT-2,thecellswhichareinmitoticphase(metaphase,anaphase,telophaseincluded)occupy19.2%.Whenthecellisinmetaphase,itschromosomeswillarrangeontheequatorofit.Butthechromosomestendtomovetothetwopolesofcellsandwecanseetheseparationclearly.Astelophase,wecanseecellstemporarilywithtwonuclei.Onthebasisofwhatweknow,thenucleusofacellinprophasestartstodisperse,butitishardtorecognizewhetherornot.Sotheproportionofthecellsinprophaseis70.8%,similartotheinterphaseinPartⅠ,muchlargerthanreality.Atthesametime,thedatashowsthatthepercentageofmetaphase,anaphaseandtelophaseis6.2%,9.2%,and13.8%respectively.Discussions：1.Whatisthefunctionofmitosisincellcycle?Mitosisisnucleardivisionpluscytokinesis,itallowsacellinherititstraitstothetwodaughtercellswhichhavenearlysamechromosomalmaterialsasit.Becauseitensurestheequaldivisionofchromosomes,andkeepsthestabilityoftheorganism.2.BesidesFeulgenstain,pleasesuggestothermethodstovisualizechromosomesinmitoticcells.Aswhatweknow,otherDNAstainlikemethylrosanilinechloride(gentianviolet),acetone-carmine,andmethylchloridecanalsodyeDNA,withdifferentofsimilarmechanism.Besides,maybewecanalsodirectlyusehigh-powerelectronmicroscope.References:Baidupedia,labmanual.Distributionstatements:HEWeiweiisresponsibleforcontrollingthetimeandrecordthephenomenawhatwesee,andLIUZhichaomaketheslideofgarlicroottip.Atthesametime,LinJirongistheonewhoobservetheslidewithlightmicroscopeandtakephotoswithhisswindowsphone.Figures:ABFigure1-1.1(10×40)ThedataintableT-1isbasedon3columnsofcellsinthisfigure.Awith2nucleirepresentsthecellinmitoticphase,andBrepresentsthecellsininterphase.Figure1-1.2（10×40）Figure1-1.3（10×40）Theyarethecellsindifferentregionofonionroottip.Figure1-1.4(10×40)Figure1-1.5(10×40)Thesepicturesaretakenatdifferentlocationoftheonionroottip.BFigure2-1(10×40)Aisthecellinmetaphase,andBrepresentsthecellwhichisinanaphase.Figure2-2thewholeview.第頁

第二篇：填料塔氣體吸收實驗_實驗報告_英文12400字DivisionofEngineeringAssessedReportDepartmentofChemicalEngineeringEH1SPF:GasAbsorptioninapackedcolumn1AbstractPackedtoweriswellknownasoneofthemostwildlyusedmethodinabsorptionzonetoseparatedifferentgasbyliquidphase.Inthisexperiment,theaimistocalculatetheoverallliquidtransfercoefficientKxabytheequation??=????=0??1??????????????2???????=??????.??????ThevalueofKxainthreegroupsarechangeableandonlytwoofwhichcanworkoutKxavalue.TheKxavalueofgroup2andgroup3is0.014and0.012.Inaddition,boththeKxavalueisbelow1sothatlog(Kxa)isalwaysnegative.Moreover,theGandHoLhaveapositivelinearratio.However,GandKxahaveanegativerelationship,sodoesKxaandHoL.Thesethreediagramsillustratethatthegasflowratehasnegativeinfluenceontheefficiencyofgasabsorption.Andtheheightofatransferunitalsohasaninverseratiototheefficiency.2ContentAbstract....................................................................................................2Content....................................................................................................3Objectives.................................................................................................4Introduction..............................................................................................4Backgroundtheory.....................................................................................5Apparatus.................................................................................................7Procedureandnotes...................................................................................8Calculationandresults:..............................................................................9Discussion:.............................................................................................13Conclusion:.............................................................................................15Referencelist:.........................................................................................153ObjectivesThisexperimentisdesignedforstudyingthetheoryofhydrodynamicsandabsorptionprocessesinapackedtower.Improvetheskillofsolvingopen-endedquestionisalsoexpectedinthisexperiment.IntroductionAbsorptionisatypicalmasstransferprocesswhichiswidelyusedinseparationprocess.Theremovalofoneormoreselectedcomponentsfromamixtureofgasesbyabsorptionintoasuitableliquidisthesecondmajoroperationofchemicalengineering.Packedtoweriswildlyusedasoneoftheoutstandingrequirementstoabsorbwithdifferentphasesolventinbothindustryandlaboratory.Inthisexperiment,amixtureofCO2andairisutilisedinthepackedtower,andCO2isconsideredasthetargetgaswhichshouldbeabsorbed.WaterisusedassolventliquidtosoluteCO2.Bymeasuringtheinletandtheoutletconcentration,CO2absorbedcanbedetermined.4BackgroundtheoryThemeasureoftheefficiencyoftheabsorptionprocesscanbeexpressedinthetermsofoverallheightofliquidfilmtransferunit,HOL.ThesmallertheHOLis,themoreefficienttheabsorptionprocesswillbe.Theheightofthecolumn(m)Zisdefinedas:????1??????=????==??????.????????????20Where,??KXAisavariablewhichcanindicatetheefficiencyofgasabsorption.AsKXA=L/HOL,itcanbedeterminedthatthelargerKXAvalue,thebetterefficiencyofthesystem.Andtheabsorptionfactorisdefinedas:??=??/????Where,ThebalanceequationisyA=mxA5Wherem=E/PEisthehenry’sconstant,E=f(t)PisthetotalpressurexAisthemolarfractionofthecontaminantinthegasphaseatequilibrium.yAisthemolarfractionofthecontaminantdissolvedintheliquidphaseatequilibriumAfterAisgiven,thefollowingequationcanbeusedtodeterminethenumberoftransferunitsbasedonoverallliquidfilmcoefficient(??????):??????=Where,Followstepsneedtobedoneinthisexperiment,?Determinationofgasflowrateandliquidflowrate?Determinationoftheheight(Z)ofthepackingandthediameter(D)ofthecolumn?Determinationofy1andy21??1?????2ln1???+??11Fordataanalyse,alog-logdiagramwillbeusedinthisexperiment.Itisatwo-dimensionalgraphofnumericaldatathatuseslogarithmicscalesonbothaxes.Morespecific,inCartesiancoordinationtheunitis1whileinthelog-logsystem,theunitforbothaxesarethelogX.6Apparatus1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18-19-20-21-liquidoutletV4airblowerliquidoutletV5gasoutletoutletgassamplingUtubemanometerPackingLiquiddistributorInletgassamplingGasflowmeterGasflowmeterLiquidflowmeterGasinletvalveV1GasinletvalveV2LiquidinletvalveV3WatertankWaterpumpLiquidinlettemperatureMixedgastemperatureBlowerbypassvalveProcedureFigure1,theCADdiagramofexperimentalapparatus.Specification:heightofthecolumnis2000mmDiameterofthecolumnis100mm7Procedureandnotes?Checkthevalveatbottomofgasmixertoletcondensateout.?Turnonthepoweratthepanel,turnonthegauge.?Fillthewatertankwithtapwaterandcheckthelevelperiodically,keepitinastablerange.?Switchonthewaterpump.Adjusttheliquidinletvalvetoachieveadesertwaterflowrate.OperateV4andV5tocontrolthewaterlevelatbottomofthecolumnbelowtheairinlet.?Turnontheairblower.TurnontheCO2cylindervalveandthereadingislargerthan3?V1andV2arethevalvethatadjustCO2rotameter(suggestedgasflowrateis3-5m3/h,liquidflowrateis0.6-0.8m3/h,CO2flowrateis2-3L/min)?Letthecolumnrunforafewminutes,duringthetimeyoucanadjustlevelwater,pressuredroptomakesureitreaches“steady-state”conditions.?AnalysetheinletgasandoutletgasrespectivelybyGC:open(inlet/outlet)valve---(2min)---turnonthesamplebottom---click“start”---closesamplevalve—close(inlet/outlet)valve?RecordingallthenecessarydataNotes:?Thewaterlevelshouldkeepinastablerange;neverthelessitwillcauseinstabilityofrotameterofliquid.?ThetotalgasflowrateequalsthesumflowofV1andV2?BeforesamplingtotheGC,opentheinlet/outletvalvefor1-2minutessothatmeasuredgascouldfillupwithpipe.Otherwise,theoutletcarbondioxidepercentagemaybelargerthaninletoneintheresult.8Calculationandresults:Thedataofthreegroupsarelistedasfollowing:Chosegroup1asanexample:Tosimplifythecalculation,roomtemperatureisassumedas25?Candtheroompressureis1atm.m=E/PThehenry’sconstantofcarbondioxidedissolvedinwaterat25?C1atmcanbefoundbylookinguptheengineeringhandbookwhichis1635atmThus,m=1635/1=1635(dimensionless).Fromtheexperimentdata,L=0.6*998/18=32.267kmol/hG=PV/RT=1*10.06/(0.082*298)=0.412kmol/hY1=5.493%Y2=5.308%Accordingtothebalanceequation:L*(X1-X2)=G*(Y1-Y2);X2=0X1=G*(Y1-Y2)/L=0.412*(5.493%-5.308%)/32.267=2.362*10-59Inaddition,A=L/mGThus,A=32.267/(1635*0.412)=0.048TakeAintotheequation??????=Thus,??????=1?0.048ln1?0.0485.493?1635×2.362×10+0.048=1.239Because,??1????????=????==??????.??????????0??2??15.4931??1?????2ln1???+??11Then,??????=????????=21.239=1.614;L=4×32.2673600=1.142log(HOL)=0.208log(KXA)=log(L/HOL)=-0.150log(G)=log(0.412*1000)=2.615Accordingtoprocessabove,othertwogroupscanbedeterminedaswellintheTable2.10Afterwards,thelog-loggraphcanbedrawnTable3OLFigure2showstherelationshipbetweenlog(G)andlog(HoL),whichhasadirectproportionwithpositive.Thefunctionisabouty=0.0832x+0.1271XAFigure3isthediagramofTable4thatindicatesthatthereisanegativerelationshipbetweenlog(Kxa)andlog(G),whichhasadirectproportionwithnegative.Thefunctionisabouty=-0.0832x-0.069511OLXAFigure4showstherelationshipbetweenlog(Kxa)andlog(HoL)directlywhichillustratestheyhavealinearrelation.Thefunctionofthelineisabouty=0.0832x+0.1271Figure5OperatinglineandequilibriumlinesFigure5showstheoperatinglineinthesituationofdifferentinletgasflowratecomparetothesameequilibriumline.Theslopeofoperatinglineandequilibriumlinehasabigdifference.However,whenx=0,thesethreeoperatinglinesarenotequals0.Asaresult,theremusthaveintersection,inotherwords,itexistsminimumflowrate.12Discussion:ExperimenterrorsReadingerrorsinthisexperimentcannotbeavoided.Itwillbemainlycreatedinreadingtheflowrateofbothliquidandgas.Thetemperatureoftheroomkeepschangingduringtheexperiment,whichcertainwillmakeintersection.Thedeviceitselfhaserror.ForexampleCO2gasmayberevealedfromtheapparatusatsomecomponents.Thereaddingwrittenisnoinstable-stateBeforeenterthesampletoGCmachine,thevalvemaybenotimmersedbymeasuredgascompletely,whichbecausetherearesomeimpuritiesinthesampleandtheresultisinfluenced.Inaddition,theerrorwillbeveryobviouslyduetothesensitivityofGC.Calculationerrors:Thefirstnotablethingduringthecalculationistheunits.Mistakesareeasytobemadeifunits’transformationsarenotgettingenoughattention.Thelog-logdiagramdrawnaccordingtotheresultsoftheexperimentisnotexactlystraightlinesandthefunctionofthegraphisestimated,thus,thisexperimentmusthaveintersectionorsmallerrors.Tomakethecalculationeasytoget,wehaveassumedtheroomtemperatureis25?C;however,theroomtemperatureoftheexperimentisnearly21.8?C.Theinaccurateofthetemperaturewillmakethehenry’sconstantofcarbondioxidedissolvedinwaterweuseincalculationisnottheactuarialone,anditwillmakeadifferenceinresults.13OneofthereasonstochoosetheHenry’sconstantunder25?Cisthatitiscommontobeusedasstandardsituation,theotherisitisneartherealvaluerelatively.Duetotheexperienceofformerexperiment,theinfluenceofKxaandHoLforpackingcolumnisthatthelargerKxais,themoreefficiencycolumnwillhas.Onthecontrary,largeHoLvaluemeanslowabsorptionefficiency.Moreover,dependingonthethreelog-logdiagrams,log(G)-log(HoL),