相关试题
【单选题】
使用___则是保持油液清洁的主要手段（易）
A. 液压马达
B. 液压缸
C. 液压泵
D. 滤油器
【单选题】
___是实现液压放大的回路（易）
A. 增压回路
B. 减压回路
C. 调压回路
D. 平衡回路
【单选题】
___是利用电磁铁推动阀芯移动控制油流方向的（易）
A. 电磁换向阀
B. 减压阀
C. 调速阀
D. 顺序阀
【单选题】
方向控制阀主要有单向阀和___（易）
A. 电磁换向阀
B. 换向阀
C. 调速阀
D. 顺序阀
【单选题】
压力控制阀主要有减压阀和___（易）
A. 单向阀
B. 换向阀
C. 调速阀
D. 顺序阀
【单选题】
流量控制阀主要有调速阀和___（易）
A. 单向阀
B. 换向阀
C. 调速阀
D. 节流阀
【单选题】
下列属于换向阀的是___（易）
A. 单向阀
B. 顺序阀
C. 三位四通换向阀
D. 节流阀
【单选题】
___主要功用是保持系统压力的恒定和防止液压系统过载，起安全保护作用。（易）
A. 溢流阀
B. 顺序阀
C. 单向阀
D. 节流阀
【单选题】
___一般用在压力较低或流量较小的场合
A. 直动型溢流阀
B. 顺序阀
C. 单向阀
D. 节流阀
【单选题】
___的作用是用来降低液压系统中某一油路的压力，以满足执行机构需要的。（易）
A. 溢流阀
B. 减压阀
C. 单向阀
D. 节流阀
【单选题】
___只适用于负载和温度变化不大或速度稳定性要求较低的液压系统（中）
A. 溢流阀
B. 减压阀
C. 单向阀
D. 节流阀
【单选题】
___的作用是利用阀芯和阀体间相对位置的改变，来控制油液流动方向（中）
A. 溢流阀
B. 换向阀
C. 单向阀
D. 节流阀
【单选题】
工作中应随时注意油位高度和温升，一般油液的工作温度___度在较合适（易）
【单选题】
对于新投入使用的设备，使用___个月左右应清洗油箱，更换新油（中）
【单选题】
定期检查的时间间隔，一般与过滤器的检修期相同，通常为___个月（中）
【单选题】
在液压系统中，利用压力控制阀来控制系统中油液的压力，称为___（中）
A. 方向控制回路
B. 压力控制回路
C. 顺序控制回路
D. 平衡锁紧回路
【单选题】
___是控制和调节液压执行元件的运动速度的基本回路（易）
A. 速度控制回路
B. 压力控制回路
C. 顺序控制回路
D. 平衡锁紧回路
【单选题】
___按输出的流量能否调节可分为定量泵和变量泵（易）
A. 液压马达
B. 液压缸
C. 液压泵
D. 滤油器
【单选题】
___一般用于实现回转运动（易）
A. 液压马达
B. 液压缸
C. 液压泵
D. 滤油器
【单选题】
___的作用式只允许油液按一个方向流动，不能反向流动（中）
A. 单向阀
B. 换向阀
C. 调速阀
D. 顺序阀
【单选题】
按阀芯运动方式不同，___可分为滑阀式和转阀式两类（中）
A. 单向阀
B. 换向阀
C. 调速阀
D. 顺序阀
【单选题】
压缩比为7.0~8.0的汽油机应选用___号汽油（易）
【单选题】
___能保持出油口压力基本不变，而溢流阀是保持进油压力基本不变（中）
A. 单向阀
B. 换向阀
C. 减压阀
D. 顺序阀
【单选题】
消防装备用燃料有___和气体燃料两大类（中）
A. 工业燃料
B. 环保燃料
C. 液体燃料
D. 自然燃料
【单选题】
___是将旋转物体的转速转换为电量输出的传感器（中）
A. 压电传感器
B. 开关传感器
C. 长度传感器
D. 转速传感器
【单选题】
___中主要使用的材料包括有石英、酒石酸钾钠和磷酸二氢胺（中）
A. 压电传感器
B. 开关传感器
C. 长度传感器
D. 转速传感器
【单选题】
自动控制主要分为开环控制和___（中）
A. 自然控制
B. 外力控制
C. 工业控制
D. 闭环控制
【单选题】
___结构简单、稳定性好，但不能自动补偿扰动对输出量的影响（中）
A. 开环控制系统
B. 闭环控制系统C、自动控制系统 D、液压控制系统
【单选题】
___实际就是一种反馈控制（中）
A. 开环控制系统
B. 闭环控制系统C、自动控制系统 D、液压控制系统
【单选题】
___会使系统的稳定性变差（中）
A. 开环控制系统
B. 闭环控制系统C、自动控制系统 D、液压控制系统
【单选题】
___是由在轴上加工出的外花键齿和在轮毂孔加工出的内花键齿所构成的联接。（中）
A. 花键连接
B. 平键连接C、轴承连接接 D、齿轮连接
【单选题】
容积泵正常工作的必备条件有：吸油过程中，___必须和大气相通（易）
【单选题】
液压泵能实现吸油和压油，主要是泵的，___（易）
【单选题】
串联电路中，某一电阻值与总电阻值之比，称为分压比（或分压系数），用字母___表示。（易）
A. “K”
B. “I”
C. “U”
D. “R”
【单选题】
蓄电池的容量，是在放电允许范围内，蓄电池所输出的电量，它表示蓄电池的供电能力，用字母___表示。（易）
A. “I”
B. “Q”
C. “U”
D. “K”
【单选题】
“I”的单位是___，“t”的单位是（ ），“Q”的单位是（ ）。（易）
A. 小时(h) 安(A) 安时(Ah)
B. 安(A) 小时(h) 安时(Ah)
C. 安时(Ah) 安(A) 小时(h)
D. 小时(h) 安时(Ah) 安(A)
【单选题】
电池___后，总内阻等于各单个电池内阻之和。（易）
【单选题】
划线平台又称划线平板，用铸铁制成，它的上平面经过精刨或刮削，是划线的___平面。 （难）
推荐试题
【单选题】
Death rates declined in many places, partly because of the ___ in hunger.
A. decrease
B. myth
C. obstacle
D. burden
【单选题】
In deciding whether or not a situation is safe, pilots must be taught to assume that the worst will happen, and then to ___ whether there is a risk or not.
A. absorb
B. apply
C. assess
D. occupy
【单选题】
The worker was not worried as he knew that if he gave up the job, there would be ___ opportunities for him to work somewhere else.
A. formative
B. marginal
C. vigorous
D. numerous
【单选题】
The research shows the region might ___ overheating (经济过热), but the policymakers so far appear to be relatively relaxed about the future of the economy.
A. catch a glimpse of
B. be at risk of
C. take a toll on
D. be free from
【单选题】
Measures have been taken to ensure that no student will have to ___ of college for economic reasons.
A. lay out
B. cancel out
C. drop out
D. stand out
【单选题】
Stress that is not treated can lead to significant medical illnesses, which ___ can lead to greater stress and even depression (抑郁症).
A. after all
B. in turn
C. on the contrary
D. at least
【单选题】
Narcissism (自恋) has its benefits in terms of self-belief and confidence, but it also tends to be ___ risky decision-making.
A. associated with
B. contrasted with
C. reserved for
D. relieved of
【单选题】
When Tom saw his doctor again, she suggested that maybe a more substantial lunch, like a sandwich, might ___ his desire to have snacks in the afternoon.
A. count on
B. cut back on
C. hold on to
D. contribute to
【单选题】
You shouldn’t ___ – let your children make their own decisions.
A. interact
B. abuse
C. startle
D. interfere
【单选题】
This is a huge and difficult project and if you take it up, you ___ many difficulties.
A. like to encounter
B. like encountering
C. are likely to encounter
D. are like to encounter
【单选题】
The ability to live for a long time without water is characteristic ___ the camel.
A. of
B. for
C. about
D. in
【单选题】
Rising sales is a good ___ that this product is well received in the market.
A. response
B. convention
C. indication
D. Influence
【单选题】
When tourists travel abroad, they are sometimes ___ by the local people because the tourists don’t know the real value of products.
A. turned in
B. given chase
C. wrapped up
D. ripped off
【单选题】
The professor’s lecture ___ the capacity of his young audience. They all looked puzzled at him.
A. pointed out
B. went beyond
C. contributed to
D. kept off
【单选题】
We must ___ on the amount of time we use on this project.
A. cut both ways
B. cut in line
C. cut off
D. cut down
【单选题】
We have to be very patient with this experiment. It will take time for some effects to ___ clearly.
A. build up
B. break up
C. clear up
D. show up
【单选题】
Perhaps there is a(n) ___ of truth in both theories, but few of us would ever have the opportunity to find out.
A. lump
B. substance
C. section
D. element
【单选题】
Be careful when you get along with her because she is known for her short ___.
A. temper
B. emotion
C. mood
D. feeling
【单选题】
It seems that wearing less formal clothing to school and work is becoming a(n) ___.
A. trend
B. campaign
C. goal
D. occurrence
【单选题】
You cannot correct children’s bad behavior simply with a (n) ___ or two on the hand or face.
A. slap
B. smash
C. slam
D. strike
【单选题】
Our investigations (调查) ___ something very surprising – many of the employees are underpaid and work overtime all the time.
A. reveal
B. bump
C. rip
D. frustrate
【单选题】
She was James’s faithful assistant, in whom he could have ___ confidence.
A. essential
B. automatic
C. ultimate
D. absolute
【单选题】
If you visit this website, you can ___ the categories to find information about all the universities in that area.
A. observe
B. browse
C. glance
D. look
【单选题】
Making New Year’s resolutions (计划) is a custom that still ___ in this country.
A. prevails
B. attaches
C. descends
D. launches
【单选题】
The military officers were more ___ about their own victory and therefore more willing to predict their enemy’s defeat.
A. appropriate
B. ignorant
C. negative
D. optimistic
【单选题】
___ is no doubt that overwork and much worry caused his illness.
A. It
B. There
C. Here
D. This
【单选题】
___ a day goes by that I don’t receive dozens of junk mails in my email box.
A. None
B. Usually
C. Nearly
D. Hardly
【单选题】
Please trust me. Try this new method ___.
A. you feel very relaxed
B. and you feel very relaxed
C. you will feel very relaxed
D. and you will feel very relaxed
【单选题】
John said Mom was coming back tomorrow, not next week. If this is the ___, we’ll all have to clean the house thoroughly.
A. point
B. norm
C. question
D. case
【单选题】
It is far too late for you to go out and play football, ___ the fact that it’s raining.
A. no doubt
B. despite
C. given
D. not to mention
【单选题】
However, under no circumstances should we ___ our achievements, nor should we regard our accomplishments as unimportant.
A. present
B. perceive
C. exemplify
D. exaggerate
【单选题】
Jane picked up a magazine from the bookshelf and started reading here and there ___.
A. accurately
B. randomly
C. emotionally
D. continually
【单选题】
In many Middle Eastern cultures a deadline is taken as a(n) ___, and such terms should not appear in a purchase contract with businessmen from these countries.
A. target
B. favor
C. honor
D. insult
【单选题】
He is by no means a(n) ___ man. On the contrary, he always departs from customs.
A. disgraceful
B. sophisticated
C. traditional
D. intelligent
【单选题】
Although the nuclear radiation problems remain unsolved, the government’s emphasis has been ___ from coal to nuclear.
A. intended
B. defined
C. attached
D. switched
【单选题】
The psychologist doesn’t say directly, but seems to ___ that emotional maturity and self-stimulation are the key elements for success.
A. inquire
B. imply
C. refer
D. confront
【单选题】
The top floors of a building collapsed, trapping a construction worker in the rubble (瓦砾), but he was ___ and could talk to rescuers.
A. reasonable
B. rational
C. innocent
D. conscious
【单选题】
After ___ research by the local government, officials confidently stated that this area of the sea was much safer than before.
A. extensive
B. durable
C. partial
D. extreme
【单选题】
As the world is becoming global, it is increasingly important that countries work together to ___ international trade.
A. soar
B. rise
C. facilitate
D. prompt
【单选题】
As the technology develops, it is probable that electronic books will start to ___ paper books in the near future.
A. ban
B. exchange
C. employ
D. replace
