问题 问答题 简答题

简述废热锅炉温度超高的原因及处理。

答案

参考答案:

原因:1、酸性气含烃类高;

2、酸性气硫化氢浓度高且气量小;

3、配风偏大;

4、仪表失灵;

5、锅炉干锅。

处理:1、做酸性气全分析,查找含烃高的原因;

2、炉前注蒸汽或氮气;

3、分析配风情况,调整配风;

4、查找仪表使用情况;

5、紧急停工。

单项选择题
阅读理解

C

The largest television network in America is not ABC, CBS, or Fox. Nor is it one of the cable net—works such as CNN, which carries only news and news stories. It is not ESPN, the all-sports cable net-work, or even MTV, which is famous for its music videos. Rather it is PBS, Public Broadcasting System, a non-profit public broadcasting TV service. PBS has 349 member television stations in the U. S. and some member stations by cable in Canada.

PBS only attracts a minority of all TV viewers, about 2 percent. The industry leader, NBC, however, attracts 11 percent of viewers. But the growth of public television in the past two decades has been dramatic. This is especially noteworthy when one considers that public television stations must often survive on very limited budgets, on viewers’ donations, and on private foundations and some governmental funding.

The level of quality of PBS programs, whether in national and international news, entertainment, or education, is excellent. Almost a whole generation of children throughout the world is familiar with Sesame Street and the characters of The Muppet Show. PBS is especially well known for the quality of its many educational TV programs. Over 95 percent of all public television stations have tele-courses. These courses are accepted and supported by more than 1,800 colleges and universities throughout the US. Each year, over a quarter of a million students take courses this way.

59.According to this article, PBS received part of its funding from._______.

A. private organizations                                                B. public schools

C. advertising agencies                                                  D. other television stations

60.What is PBS most famous for?

A. Cable services.                                                            B. Generous donations.

C. Educational programs.                                              D. Live news broadcasts.

61.Which of the following is true about public television stations?

A. The majority of their viewers are minority people.

B. Ninety—five percent of their programs are tele—courses.

C. They are shrinking in number because they make no profits.

D. Their courses are accepted by many universities in America.

62.Which of the following has the highest percentage of viewers?

A ABC                                   B. PBS                                   C. NBC                                 D. Fox