【判断题】
[108]危急保安器动作后，转速可在任何情况下进行机组复位
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[110]发生喘振时，机组进汽量波动大，转速波动大，严重可能导致轴瓦损坏
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[111]一般物体都是受热时冷缩，冷却时膨胀
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[112]物质在升华过程中要放出热量，在凝华过程中吸收热量
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[113]完成干燥作业的首要条件是根据被干燥系统
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[114]乙炔加氢过程中形成的乙烯、乙炔二聚、三聚的低聚物，是褐绿色透明状液体称为绿油
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[115]开车过程中冷泵如来不及预冷，可以不进行预冷
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[116]干燥剂冷吹时可以使用少量水蒸汽，甲烷或氮气等惰性气体
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[118]任何液体的密度都随压力和温度的变化而略有改变，但压力
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[119]在连通着的同一种静止流体内，处于同一水平面的各点压强相等，而与容器的形状无关
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[120]泵的流量不是一个固定的值，而是在一定范围内变动，如果泵的密封不好，有相当量内回流和外泄漏就会降低泵的流量
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[121]含碳元素的化合物一定是有机物
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[122]一定质量的气体，在体积不变的条件下，其压强和热力学温度（或绝
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[123]冷剂无相变时，塔顶冷凝器的负荷主要由冷剂量来调节
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[124]再生系统在系统开车前必须氮气置换合格
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[125]再生系统在系统开车前就已经开车正常
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[126]离心泵备用泵满足备用条件：润滑良好，冷却水畅通，密封面无泄漏，盘车良好，安全附件齐全好用，热油泵处于预热状态，离心泵入口阀开、出口阀关，泵内充满介
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[127]冷箱系统开车前要求裂解气压缩机运行稳定，而
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[128]每次启动前和运行初期必须充分灌泵排气，可以无液启动
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[129]一般在只需要切断而不需要流量调节的地方，为减少管道的阻力，选用闸阀
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[130]往复泵有自吸作用，安装高度没有限制
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[131]离心泵停车时，单级泵应先停电，多级泵应先关出口阀
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[133]塔罐倒空时，要先泄压，后倒空
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[134]膨胀机正常巡检时应查看油冷器冷却水是否畅通
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[135]泵内流体和泵外大气间存在着压差，流体沿着轴和壳体间的间隙向外泄露，为此需设密封装置，称其为轴封
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[136]设备的基本维护工作主要包括检查、调整、润滑、清洁卫生、状态检测
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[137]操作中一定要保证密封油建立起稳定压力以后再充入氮气，以防止氮气将机械密封密封面顶开，导致密封泄露
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[138]压力容器的人孔和检查孔打开后，必须清除所有可能滞留的易燃、有毒、有害气体，压力容器内部空间的气体含氧量应当在16%-23%(体积比)之间
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[139]汽蚀或汽蚀过程就是流动的液体产生气泡并随后发生破裂的过程
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[140]冬季,室外的泵应注意做好防冻防凝工作,在停车后不用放出泵内液体(如工艺允许时)
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[141]填料密封一般适用于输送石油及化工介质，特别是贵重，有毒及易爆介质
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[142]压力容器的安全附件包括安全阀、爆破片、压力表、液面计、测温仪表等
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[143]冬季和夏季所使用的润滑油牌号应该是一样的
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[144]安全阀按其开启度可分为：弹簧式、垂锤式、杠杆式、导向式
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[145]流体在流动时，任一截面处的流速，流量和粘度等与流动有关的量都不随时间而变化，这种流动为稳定流动
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[147]润滑油“五定”的内容是定人、定点、定时、定量、定质
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[148]安全阀阀瓣与阀座的材料必须能够抗冲击、耐腐蚀，允许使用铸铁材料
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( ) 30. After the trip to the Arctic, Clarence Birdseye invented ____________.
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( ) 32. According to the passage, which of the following may lead to inventions?
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( ) 33. What is the writer's main purpose（目的）in writing this passage？
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( ) 34. Why did the father not ask his son not to do this and do that？
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( ) 36. What may be the proper Chinese for the underlined part in the passage？
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