问题 问答题 简答题

液位开关有哪些?如何选用?

答案

参考答案:

液位开关有多种,常用的有外浮简式、浮球式、电容式、电阻式、核辐射式、超声波式等。一般液体可采用外浮筒式、浮球式、电容式、电阻式。外浮筒式液位开关的设定值在l一300mm内连续可调,有高温型、高压型、耐腐蚀型等在引进的石化、化肥装置中使用较多。浮球式液位开关以采用外浮球式为好,便于维修拆卸。液/液界面使用电容式较好;泡沫液体可采用电容式或电阻式;浆状液体和腐蚀性液体可采用电容式、核辐射式、超声波式口

完形填空
完形填空(共12分,每小题1分)
阅读下面的短文,掌握其大意,然后从短文后各题所给的A、B、C、D四个选项中,选择最佳选项。
Joe lost his arms in an accident that killed his father. Since then, he has had to depend on the     36   of his younger sister Ella. In order to take care of him, Ella became his shadow, never leaving him     37    for years. Except for writing with his toes, he was completely unable to do anything in his life. 
As they grew up together, they had their share of     38   and they would often quarrel. Then one day, Ella wanted to separate from Joe, living    39    own life. So Joe was heart-broken and didn’t know what to do.
A     40    misfortune (不幸) struck Rosa, too. One night her mother, who suffered(受苦) from mental illness,     41    . So her father went out looking for her mother. She tried to cook meals for her parents, only to overturn the kerosene light on the stove, resulting in a fire which took her hands away.
Though her elder sister Susan showed her willingness to take care of her, Rosa decided to be    42    independent. And most of all she learned to do things on her own. Once she wrote the following in her composition: “I’m lucky. Though I lost my arms, I still have legs. Though my wings are broken, my heart can still     43  .”
  One day,Joe and Rosa were both invited to a television interview program. Joe told the TV host about his     44    future at being left on his own, while Rosa was full of hope for her life. They both were asked to write something on a piece of paper with their toes. Joe wrote:My younger sister’s arms are my arms;     45     Rosa wrote: Broken wings, flying heart.
They had both stood the same sufferings, but their different     46    determined(决定) the nature of their lives. It is true that life is unpredictable. How you deal with misfortune is the true test of your character. If you choose only to complain and run away from the suffering,it will always     47    you wherever you go. But if you decide to be strong, the hardship will turn out to be a fortune on which new hopes will arise.
小题1:
A.legsB.armsC.eyes D.hands
小题2:
A.sad B.afraidC.worriedD.alone
小题3:
A.questions B.accidentsC.problems D.business
小题4:
A.hisB.herC.myD.their
小题5:
A.seriousB.suddenC.terribleD.similar
小题6:
A.returnedB.disappearedC.movedD.left
小题7:
A.completely B.directlyC.seriouslyD.immediately
小题8:
A.breakB.beatC.flyD.jump
小题9:
A.unfairB.uncertainC.unsafeD.undoubted
小题10:
A.andB.so C.whileD.or
小题11:
A.opinionsB.valuesC.sensesD.attitudes
小题12:
A.followB.catchC.disturbD.hurt
单项选择题