上海七年级第二学期数学期末数学考试试卷-(8)

在高压缸排汽的总管上装有动力控制止回阀，以便在事故情况下切断，防止蒸汽返回到汽轮机，引起汽轮机超速。在高压缸排汽总管的端头有蒸汽冲洗接口，以供在管道安装完毕后进行冲洗，在管道冲洗完成后用堵头堵死。centerpinchecksandanchoringtheinnercylinder.AccordingtoWhilecouplingalignmentshouldkeepoiloutofcavityandlocatetherotoraxisneckraisedarewithintheprescribedlimits,thereshouldbenogaps,Horn,HornandHorn0.05mmfeelergaugesfitinto.Centercoupling,condenserwaterfillingandwater-filledaccordingtofactoryrequirement.ForcouplingthreesupportedrotorCenter,themouthunderthecouplingbetweenthevalueshouldbeasstipulatedinthemanufacturer,usually0.15~0.25mm.Inthecaseofcouplingconnection,ifpossible,liftingonlyonebearingendofthesupportbearingoftherotor,removethebearing,fittedwithspecialtilesandspecialliftingtools,discrotors,checkthejournalfluttertile,shouldgenerallybelessthan0.10MM.Whenthecouplingsandrotorcomeswhenthereisaconflict,thecouplingCentreshallprevail.6.4.5.2.2shaftlookingfor:...6.4.5.3.Provisionalboltconfirmedthepositioningoftherotorsize,aswellasthecouplingbetweentheadjustmentshimthicknessaccuracy,drawingstomeetthetechnicalrequirements.Plane,cylindricalandcleanthecouplingboltholesshouldbecleanandwithoutburrs,scrapironandgrease-free,relativepositionofthecouplingaccordingtothedrawingrequirementsare.Couplingtopscrews,rounddistanceapart,indicatorstomonitormovementoftheaircraft,itsvalueisallowedtopassthevalueaxismoving,mountedadjustmentpads,notepadsinstallationdirectionguidepincouplingwithprocessendclosed.Thebackwheelsslowlytightened,when2mmorso,withstandardwhitebarswheretwobackwheelboltholemeasurementaboveandbelow,confirmtwobackwheelboltholeconcentricity.Then,thesymmetricalhorizontalmounttwotemporaryboltstightened,attentiontomonitordialindicator,theninstallthesymmetricaltemporarybolts,thistimesitesslowlymovingrotor,inthemeasuredcircumferenceof8equalpartsbackwheelrimrock,eachmeasuringrelativechangesinvalueshouldbelessthan0.02mm.6.4.5.4couplingreamedandpairedboltreamingdiereamer,adjustablereamers,boringmill,inseveralways.6.4.5.4.1Generalrequirementsbeforereamingorboring,上海七年级第二学期数学期末数学考试试卷静安区“学业效能实证研究”学习质量调研八年级第二学期数学学科总分：120分完卷时间：100分钟2009.6一、选择题：（本大题共6题，每题3分，满分18分）【每题只有一个正确选项，在答题纸相应位置填涂】1．一次函数kxky)1(中，y随着x的增大而减小，那么k的取值范围是（A）0k；（B）0k；（C）1k；（D）1k．2．下列方程中，有实数根的方程是（A）x2+3=0；（B）x3+3=0；（C）0312x；（D）03x．3．用换元法解分式方程035512xxxx时，如果设yxx1，那么原方程可化为（A）05322yy；（B）03522yy；（C）0532yy；（D）0352yy．4．在梯形ABCD中，AD//BC，AB=CD，那么下列结论中正确的是（A）AB与DC是相等向量；（B）AC与BD是相等向量；（C）AD与CB是相反向量；（D）AD与CB是平行向量．5．在四边形ABCD中，AC与BD相交于点O，要使四边形ABCD是平行四边形应符合下列条件中的（A）AB//CD，BC=AD；（B）AB=CD，OA=OC；（C）AB//CD，OA=OC；（D）AB=CD，AC=BD．6．掷一枚普通的骰子，那么下列事件中是随机事件的为（A）点数小于1；（B）点数大于1；（C）点数小于7；（D）点数大于7．二、填空题：（本大题共12题，每题3分，满分36分）【请将结果直接填入答题纸的相应位置上】7．计算：CACBAB_____________．8．方程023xx的根是_____________．9．方程xx2的根是______________．10．方程0112xx的根是_____________．11．把二次方程49622yxyx化成两个一次方程，那么这两个一次方程分别是_______和________．12．一次函数的图像经过点（0，3），且与直线12xy平行，那么这个一次函数的解析式是___________．在高压缸排汽的总管上装有动力控制止回阀，以便在事故情况下切断，防止蒸汽返回到汽轮机，引起汽轮机超速。在高压缸排汽总管的端头有蒸汽冲洗接口，以供在管道安装完毕后进行冲洗，在管道冲洗完成后用堵头堵死。centerpinchecksandanchoringtheinnercylinder.AccordingtoWhilecouplingalignmentshouldkeepoiloutofcavityandlocatetherotoraxisneckraisedarewithintheprescribedlimits,thereshouldbenogaps,Horn,HornandHorn0.05mmfeelergaugesfitinto.Centercoupling,condenserwaterfillingandwater-filledaccordingtofactoryrequirement.ForcouplingthreesupportedrotorCenter,themouthunderthecouplingbetweenthevalueshouldbeasstipulatedinthemanufacturer,usually0.15~0.25mm.Inthecaseofcouplingconnection,ifpossible,liftingonlyonebearingendofthesupportbearingoftherotor,removethebearing,fittedwithspecialtilesandspecialliftingtools,discrotors,checkthejournalfluttertile,shouldgenerallybelessthan0.10MM.Whenthecouplingsandrotorcomeswhenthereisaconflict,thecouplingCentreshallprevail.6.4.5.2.2shaftlookingfor:...6.4.5.3.Provisionalboltconfirmedthepositioningoftherotorsize,aswellasthecouplingbetweentheadjustmentshimthicknessaccuracy,drawingstomeetthetechnicalrequirements.Plane,cylindricalandcleanthecouplingboltholesshouldbecleanandwithoutburrs,scrapironandgrease-free,relativepositionofthecouplingaccordingtothedrawingrequirementsare.Couplingtopscrews,rounddistanceapart,indicatorstomonitormovementoftheaircraft,itsvalueisallowedtopassthevalueaxismoving,mountedadjustmentpads,notepadsinstallationdirectionguidepincouplingwithprocessendclosed.Thebackwheelsslowlytightened,when2mmorso,withstandardwhitebarswheretwobackwheelboltholemeasurementaboveandbelow,confirmtwobackwheelboltholeconcentricity.Then,thesymmetricalhorizontalmounttwotemporaryboltstightened,attentiontomonitordialindicator,theninstallthesymmetricaltemporarybolts,thistimesitesslowlymovingrotor,inthemeasuredcircumferenceof8equalpartsbackwheelrimrock,eachmeasuringrelativechangesinvalueshouldbelessthan0.02mm.6.4.5.4couplingreamedandpairedboltreamingdiereamer,adjustablereamers,boringmill,inseveralways.6.4.5.4.1Generalrequirementsbeforereamingorboring,-2-13．如果一个多边形的内角和等于720º，那么这个多边形的边数是___________．14．已知某汽车油箱中的剩余油量y(升)与汽车行驶里程数x(千米)是一次函数关系．油箱中原有油100升，行驶60千米后的剩余油量为70升，那么行驶x(千米)后油箱中的剩余油量y=____________（升）．15．已知一次函数y=kx+