【判断题】
给水系统中，最容易发生的金属腐蚀是二氧化碳腐蚀，其特征是溃疡腐蚀
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相关试题
【判断题】
给水加氨的目的是中和水中的二氧化碳，提高给水PH值,防止系统氧腐蚀
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N2H4＋O2＝N2＋2H2O的反应中，N2H4是还原剂
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发电机内冷水一般采用除盐水或凝结水作为补充水
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根据《污水综合排放标准》，工业废水pH排放标准应为6～9
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锅炉补充水处理设备排出的废水分为两种，一种是从预处理设备中排放的含有大量沉淀的水，另一种是除盐设备排放的酸碱废水
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冷却水系统结垢主要是由于水中Ca(HCO3)2分解成CaCO3所致
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为了不使残余硬度进入水汽系统，防止受热面上结垢，除保证给水质量外，还要向炉水中投加磷酸盐，使进入锅炉中的钙镁离子形成一种不沾在受热面上的水渣，随锅炉排污除掉，这种处理方法简称磷酸盐处理
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氢气与空气混合时，当其中氢气的成分为10%～70%时，有爆炸的危险，因此氢冷发电机的机壳内要保持一定的压力，使空气不易进入
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有一交换器内的树脂层高度为2米，反洗时树脂的膨胀高度为0.8米，则反洗膨胀率为40%
【判断题】
反渗透系统加酸调节进水pH值的目的是为了防止在膜表面上产生碳酸盐水垢和膜的水解
【判断题】
反渗透膜的清洗方法有低压水冲洗法和化学药剂清洗法
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发电机内冷水的三项主要控制水质指标是电导率、pH、溶解氧
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有精处理系统的机组，给水电导率大于0.30μS/cm，属三级处理值
【判断题】
有精处理系统的机组，给水电导率大于0.20μS/cm，而小于0.30μS/cm，属一级处理值
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炉水采用固体碱化剂处理时，pH值小于8.5或大于10.0, 属二级处理值
【判断题】
炉水采用全挥发处理时，pH值低于8应立即停炉
【判断题】
澄清池运行中要控制的主要环节是排泥量和泥渣循环量
【判断题】
天然水经混凝处理后，水中的硬度有所降低
【判断题】
粒状滤料的过滤过程有两个作用：一是机械筛分；另一个是接触凝聚
【判断题】
水经Na型离子交换器处理后，水中的钙、镁盐类基本上被除去，所以水中的含盐量有所降低
【判断题】
强碱性阴树脂被有机物污染的特征是颜色变深，再生后正洗所需时间延长，出水水质变差，交换容量下降
【判断题】
离子交换树脂的孔隙率对交换速度没有影响
【判断题】
锅炉补给水处理中超滤、微滤是用来除去水中的硬度
【判断题】
锅炉补给水处理通常包括预处理和除盐两部分
【判断题】
反渗透产品水管装设爆破膜是为了防止运行人员疏忽，忘记打开产品水出口阀门而造成系统憋压损坏设备
【判断题】
反渗透停运后必须进行冲洗，对于冲洗水水质没有要求
【判断题】
膜的脱盐率，可近似通过电导率计算，公式为：（DD进－DD出）/DD进×100%
【判断题】
反渗透给水含盐量的增加不影响透过量和产品水通量
【判断题】
膜元件中心管的O型密封圈密封不严，会导致进水未经反渗透膜处理直接进入产水侧，造成产水含盐量增高
【判断题】
反渗透保安过滤器的主要作用是为了确保进入反渗透膜的水质不含有可划伤膜片的颗粒物质
【判断题】
用反渗透装置的出水作为一级除盐设备的进水，可大大减轻COD对强碱阴树脂的污染
【判断题】
反渗透水处理装置运行时开启或关闭进水阀门应快速，使其在短时间内达到额定出力
【判断题】
反渗透和电渗析除盐，都是膜分离技术的应用，其除盐原理也是一样的
【判断题】
高速混床的树脂必须采用强酸性和强碱性离子交换树脂作为交换剂
【判断题】
凝结水精处理系统混床失效树脂反洗分层后阳树脂从设备底部水力输送到阳再生罐
【判断题】
凝结水精处理混床和树脂捕捉器的完好性必须定期检查，防止凝结水混床在运行过程中发生跑漏树脂
【判断题】
精处理树脂投运前应充分正洗，防止树脂中的残留再生酸带入水汽系统造成炉水pH值大幅降低
【单选题】
驻守站是指___的站场。
A. 无人值班、有人值守
B. 有人值班、有人值守
C. 有人、无人值守
D. 无人值班、无人值守
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【单选题】
With a good command of English, he soon got ___ to working with British people.
A. accustomed
B. consistent
C. relevant
D. responsible
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What needs to be ___ here is that language and culture interact, and that understanding of one requires understanding of the other.
A. altered
B. stressed
C. aroused
D. committed
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Policies and organizations must be created to meet workers’ hopes, and to ___ new problems that inevitably arise between workers and managers.
A. compromise
B. ensure
C. undermine
D. resolve
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To keep the wheels of industry turning, we produce consumer goods in endless quantities, and, in the process, are rapidly ___ our natural resources.
A. ignoring
B. collapsing
C. enduring
D. exhausting
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As a person who loves peace, he is committed ___ realizing peace between countries.
A. of
B. about
C. for
D. to
【单选题】
Learning how to use chopsticks is easy for me, ___ learning how to conduct myself at the table is quite difficult.
A. whereas
B. however
C. therefore
D. besides
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___ that the patient smokes 50 cigarettes a day, it would be reasonable to assume there is some lung damage.
A. To give
B. Giving
C. Given
D. Having given
【单选题】
Kenyan (肯尼亚的) women tend to vote for those who could provide them ___ the necessary food to live on.
A. of
B. with
C. for
D. about
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___ all obstacles and failures, the scientist continued doing his experiments day and night.
A. In spite of
B. In contrast to
C. As a matter of
D. As a result of
【单选题】
I’m willing to ___ that a larger car would have cost more, but I still think we should have bought one.
A. withdraw
B. indicate
C. abandon
D. concede
【单选题】
Manufacturing (制造) companies spend millions of pounds on advertisements, trying to ___ customers that their products are better than those of other companies.
A. confine
B. convince
C. depress
D. reconcile
【单选题】
He is not the right person for the project: he is not very technically minded and ___, he does not have the sense of responsibility.
A. instead
B. yet
C. furthermore
D. nevertheless
【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
