在点火过程中一次风应如何调整？
参考答案：
一般情况下，在点火过程中一次流化风都保持临界状态，其目的是尽量提高床温，减少热量损失。但在投油枪时应特别注意流化风量的变化，当油枪点燃时，点火风道内的空气突然受到加热膨胀，通往风室的一次风阻力增大，一次流化风总量减少，停止油枪运行时，则会出现相反的现象。所以应相应加大或减少一次风机入口导叶开度，保证一次流化风量不能低于临界量，床料保持良好的流化状态
Questions 21-25 are based on the following passage:
| I hear many parents complaining that their teenage children are rebelling. I wish it were so. At your age you ought to be growing away from your parents. You should be learning to stand on your own two feet. But take a good look at the present rebellion. It seems that teenagers are all taking the same way of showing that they disagree with their parents. Instead of striking out boldly on their own, most of them are clutching at one another’s hands for courage. They claim they want to dress as they please. But they all wear the same clothes. They set off in new directions in music. But somehow they all end up just by listening to the same record. Their reason for thinking or acting in this way is that the crowd is doing it. It has become harder and harder for a teenager to stand up against the popularity wave and to go his or her own way. Industry has firmly carved out a teenage market. These days every teenager can learn from the advertisements what a teenager should have and be. And many of today’s parents have come to award high marks for the popularity of their children. All this adds up to a greater barrier for the teenager who wants to find his or her own path. But the barrier is worth climbing over. The path is worth following. Find yourself. Be yourself. Popularity will come--with the people who respect you for whom you are. That’s the only kind of popularity that really counts. |
The author thinks of advertisements as ______.
A．original
B．influential
C．detrimental
D．authoritative