问题 问答题 简答题

单元制机组机炉参数调节主要有哪些方面?

答案

参考答案:

1.负荷调节。单元机组并入电网运行,电网中机组负荷的大小决定于外界用户的用电情况,发电负荷是随外界用电情况而改变的。

2.蒸汽温度调节。正常运行中,过热蒸汽、再热蒸汽的温度应严格控制在上、下限范围内,两侧气温的偏差也不应大于规定值,否则应予以调整。

3.锅炉燃烧的调整。锅炉燃烧调整是保证燃烧稳定性,提高燃烧热经济性,同时使燃烧室内热负荷均匀,减小热偏差,防止锅炉结焦、堵灰等现象。

4.汽包水位的调整。给水调节是锅炉安全稳定运行的重要环节,给水应连续不断地送入锅炉。汽包水位应维持在允许的波动范围内。

单项选择题

(A)

One day Walt Disney had a vision. It was a vision of a place where children and parents could have fun together. The more Walt dreamed of a "magical park," the more imaginative and elaborate it became.

The original plans for the park were on 8 acres next to the Burbank studios where his employees and families could go to relax. Although World War lI put those plans on hold. During the war, Disney had time to come up with new ideas, and creations for his magical park. It was soon clear that 8 acres wouldn’t be enough.

Finally in 1953, he had the Stanford Research Institute conduct a survey for a 100-acre site, outside of Los Angeles. He needed space to build rivers, waterfalls and mountains; he would have flying elephants and giant teacups; a fairy-tale castle, moon rockets and a scenic railway; all inside a magic kingdom he called "Disneyland".

The search for the best venue for the park ended in the rural Anaheim, California with a purchase of a 160-acre orange grove near the junction of the Santa Ana Freeway (1-5) and Harbor Boulevard.

Construction for Disneyland began on July 21, 1954, 12 months before the park was scheduled to open.

Some 160-acres of citrus trees had been cleared and 15 houses moved to make room for ’the park. However, when the real designing came around, Disney met with inevitable questions. How do you make believable wild animals, that aren’t real How do you make a Mississippi paddle ship How do you go about building a huge castle in the middle of Anaheim, California Disney asked his movie studio staff for answers. The design of Disneyland was something never done before. There would be four uniquely different theme parts: Adventureland, Frontierland, Fantasyland,Tomorrowland. Bit by bit, Disneyland got ready for opening day. The staff worked around the clock to get ready.

But opening day was a terrible disaster. Beside the terrible opening day conditions, the park did eventually pick up. By 1965, ten years after opening day, 50 Million visitors had come through the gates.

The underlined phrase in the last paragraph probably means()。

A. collect

B. improve

C. find

D. open

单项选择题 A1/A2型题