区别1,8-二羟基蒽醌与1,8-二羟基蒽酮时选用()
A. 碱液反应
B. 醋酸镁反应
C. 无色亚甲蓝试验
D. α-萘酚-浓硫酸试验
E. 浓硫酸反应
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有30个C原子,E环为六元环,C19、C20-CH3的是()
A. β-香树脂烷型
B. α-香树脂烷型
C. 羽扇豆醇型
D. 呋甾烷醇型
E. 异螺旋甾烷型
企业进行生产经营活动的实质就是一种风险行为,即有盈亏,亦会破产。因此,企业经营决策者必须对其资产有使用权、支配权。还必须具有自我约束的能力,否则一旦决策失误,轻者亏损,重者企业倾家荡产。这段话的主要观点是( )
A. 企业生产经营活动是一种风险行为
B. 企业决策不能失误
C. 企业生产经营决策者必须与企业共存亡
D. 企业生产经营决策者必须有权
Part A For questions 1-5, you will hear a discussion on the Survival of Ballet. Listen to it and fill out the table with the information you’ve heard. Some of the information has been given to you in the table. Write only 1 word or number in each numbered box. You will hear the recording twice. You now have 25 seconds to read the table below.Information about present status The money for art is getting 1 Art must compete in the 2 Art is made to sound like business Information about future The financial support totals £ 3 The Royal Opera is charging £ 4 Dancers are trained to do 5
最易溶于水的黄酮苷元是()
A. 黄芩素
B. 黄芩苷
C. 槲皮素
D. 槲皮素-7-O-鼠李糖苷
E. 飞燕草素