与大气层结稳定度和风的铅直切变有关的动力学参数,同时是一无量纲数的是()。
A.罗斯贝数
B.基别尔数
C.无量纲厚度参数
D.理查森数
参考答案:D
根据句意和中文提示,用单词的正确形式填空,每空一词。
1. Colette ____________ (坚持认为) that Hepburn was the perfect girl to play the lead role.
2. Raise the Red Lantern was a big success and Gong Li became famous ___________ (立即).
3. ____________ (浪漫) films can usually become very popular among young people.
4. Smith's heavy ____________ (喘息) made his wife not sleep.
5. When teacher died, his students all ___________ (哀悼) the loss of a good teacher.
串级调速就是利用一个或n个辅助电机或者电子设备串联在绕线式异步电动机转子回路里,把原来损失在外串电阻的那部分能量加以利用,或者回收到电网里,既能达到调速的目的,又能提高电动机运行效率,这种调速方法叫串级调速。