问题
单项选择题 B1型题
香豆素7-羟基和6-异戊烯基缩合形成呋喃环，称为（）
A.其他香豆素
B.线型呋喃香豆素
C.角型呋喃香豆素
D.线型吡喃香豆素
E.角型吡喃香豆素
答案
参考答案：B
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香豆素7-羟基和6-异戊烯基缩合形成呋喃环，称为（）
A.其他香豆素
B.线型呋喃香豆素
C.角型呋喃香豆素
D.线型吡喃香豆素
E.角型吡喃香豆素
参考答案：B
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| Talk about a real-life hero! Ten-year-old Larry Champagne from St. Louis, Missouri, 1 the brake on a runaway (失控的) school bus. He saved himself and 20 other kids on board from disaster. It all happened in one terrible 2 . On the way to school, the bus driver, Ernestine Blackman, suddenly fell asleep. Seeing the bus was running away, the other kids started to 3 , but Larry ran to the 4 and stopped the bus. "At first I thought, 'We're going to die'," says Larry, "but after I hit the brake, I felt 5 ." Larry's quick action made news all over the country. He appeared on TV shows as a 6 . The bus company gave Larry a big 7 . And his school gave him a medal of honor. "My grandmother 8 tells me to do what's right," says Larry. 9 did he know how to stop the bus? Larry is something of a mechanic (机械师). He 10 his grandfather to work on his old truck. "He gets his hands dirty," says his grandfather. One thing is for certain: Larry knows where to find the brakes. | ||||
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