问题 问答题 简答题

简述防止锅炉结氧化铁垢的方法。

答案

参考答案:

1)减少给水、炉水的含铁量。除了对炉水进行适当的排污外,主要是防止给水系统发生运行腐蚀和停用腐蚀,以减少给水的含铁量。

2)减少组成给水的各部分水中的含铁量。除了对补给水、凝结水进行把关外,还应重点监控疏水和生产返回凝结水。

3)防止锅炉局部热负荷过高,或水循环不良,使炉水中的氧化铁蒸干并发生沉积。

完形填空

第二节:完形填空(共20小题;每小题1.5分,满分30分)

阅读下面短文,掌握其大意,然后从36~55各题所给的四个选项(A、B、C和D)中,选出最佳选项。

Most of the foods we eat today were at one time or another not known to man. One by one they are   36 and became a part of our everyday  37  . Very often the person, who was the first to  38  these foods, however, had to be a person of  39  . Who, for 40  , ate the first crab(蟹)and who, the first mushroom? 

When  41  and coffee were first introduced to  42  in the eighteenth century, there were many   43  for and against their use. Some people claimed(宣称)that they were   44  , and that, if drunk over long periods of time, they would kill  45  . In Sweden, King Gustav III decided to find out whether these  46  were true or false. It  47  happened that there were two brothers who were in  48  at the time;they were twins and were almost exactly alike in every 49  . They had also been sentenced to 50  . The King decided to let them live if one of them 51  to drink several cups of tea each day and the other, several cups of  52  each day. 

Both brothers lived many years without any 53  of any kind. At last one brother who  54   to drink tea every day died at the age of 74 and   55 died a few years later. Because of the way the experiment had turned out, Sweden is today one of the countries in the world where much tea and coffee are drunk. 

36. A. introduced    B. produced      C. added          D. changed

37. A. drink          B. cost         C. diet           D. interest

38. A. cook          B. discover      C. try            D. check

39. A. success       B. courage         C. practice        D. will

40. A. free         B. ever           C. long            D. example

41. A. tea           B. tobacco       C. milk            D. chocolate

42. A. America        B. Europe        C. Africa         D. England

43. A. attempts      B. decisions      C. opinions        D. advice

44. A. different     B. common             C. plants         D. poisonous

45. A. a person       B. themselves    C. others          D. ourselves

46. A. wishes        B. decisions      C. doubts        D. conversations

47. A. so            B. very              C. too              D. much

48. A. school         B. hospital        C. danger          D. prison

49. A. day            B. way            C. part          D. photograph

50. A. death         B. dead            C. die            D. dying

51. A. agreed        B. pleased         C. allowed        D. prepared

52. A. milk           B. water           C. coffee         D. orange

53. A. food            B. problems      C. taste           D. happiness

54. A. had           B. enjoyed         C. allowed        D. insisted

55. A. others        B. other           C. another         D. the other

单项选择题