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【简答题】
用乙醇为溶剂提取金钱草中的黄酮类化合物,提取液浓缩后,酰胺柱色谱分离,以20%、50%、70%、90%的乙醇进行梯度洗脱,指出用上述方法分离四种化合物的洗脱 的先→后顺序,并说明理由。 槲 酚 槲-3-O-葡萄糖苷 洗脱先后顺序: > >
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【简答题】Children find meanings in their old family tales． When Stephen Guyer’s three children were growing up, he told them stories about how his grandfather, a banker, 1 all in the 1930s, but did not lose si...
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【单选题】650关于航空运输的局限性,以下说法不正确的是:
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声污染严重
B.
载重量小
C.
航空运输费用高，不适合低价值货物的运输
D.
保险费用高
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【多选题】紧急避险必须具备以下哪些条件（）。
A.
必须是为了避免国家、公共利益、本人或者他人的人身、财产和其他权利遇到危险而采取的
B.
必须是正在发生危险的情况下采取的
C.
必须是在不得已的情况下采取的，如果能采取其他方法避免危险，就不能实施紧急避险行为
D.
紧急避险行为不能超过必要的限度
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【简答题】下图中，长方形与平行四边形中相等的量有 长方形的（    ）=平行四边形的（    ） 长方形的（    ）=平行四边形的（    ） 长方形的（    ）=平行四边形的（    ） 长方形的（    ）=平行四边形的（    ）
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【简答题】Direction: You are required to translate the following sentences into Chinese. All the sentences are from the TED talk "How to Make Stress Your Friend". Pay attention to the context. But I fear that s...
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【单选题】在开环的CNC系统中( )。
A.
不需要位置反馈环节
B.
可要可不要位置反馈环节
C.
需要位置反馈环节
D.
除了需要位置反馈外,还要速度反馈
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【简答题】从 A、B、C、D四个选项中，选出与所给句子画线部分意义相同 或相近并能替代的那一项。 1. Hurry up! The bus will leave in a minute . [     ] A.for a minute B.a minute ago C.at once D.just now 2. We should take care not to caught or sneeze loud...
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【单选题】Thousands of families killed and many children were left without parents.
A.
is
B.
are
C.
was
D.
were
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【多选题】紧急避险必须具备以下哪些条件（）。
A.
必须是为了避免国家、公共利益、本人或者D他人的人身、财产和其他权利遇到危险而采取的
B.
必须是正在发生危险的情况下采取的
C.
必须是在不得已的情况下采取的，如果能采取其他方法避免危险，就不能实施紧急避险行为
D.
紧急避险行为不能超过必要的限度
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【单选题】An American woman received a letter from a recently married Japanese friend. The Japanese woman wrote in her letter, "My husband is not very handsome. Your husband is much more handsome than mine." Th...
A.
She was trying to her American friend that she did not like her husband very much
B.
It is uncommon in Japan to compliment one's husband.
C.
She didn't think her husband was handsome, but she liked her personality.
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相关题目：
【简答题】Children find meanings in their old family tales． When Stephen Guyer’s three children were growing up, he told them stories about how his grandfather, a banker, 1 all in the 1930s, but did not lose si...
查看完整题目与答案
【单选题】650关于航空运输的局限性,以下说法不正确的是:
A.
声污染严重
B.
载重量小
C.
航空运输费用高，不适合低价值货物的运输
D.
保险费用高
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【多选题】紧急避险必须具备以下哪些条件（）。
A.
必须是为了避免国家、公共利益、本人或者他人的人身、财产和其他权利遇到危险而采取的
B.
必须是正在发生危险的情况下采取的
C.
必须是在不得已的情况下采取的，如果能采取其他方法避免危险，就不能实施紧急避险行为
D.
紧急避险行为不能超过必要的限度
查看完整题目与答案
【简答题】下图中，长方形与平行四边形中相等的量有 长方形的（    ）=平行四边形的（    ） 长方形的（    ）=平行四边形的（    ） 长方形的（    ）=平行四边形的（    ） 长方形的（    ）=平行四边形的（    ）
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【简答题】Direction: You are required to translate the following sentences into Chinese. All the sentences are from the TED talk "How to Make Stress Your Friend". Pay attention to the context. But I fear that s...
查看完整题目与答案
【单选题】在开环的CNC系统中( )。
A.
不需要位置反馈环节
B.
可要可不要位置反馈环节
C.
需要位置反馈环节
D.
除了需要位置反馈外,还要速度反馈
查看完整题目与答案
【简答题】从 A、B、C、D四个选项中，选出与所给句子画线部分意义相同 或相近并能替代的那一项。 1. Hurry up! The bus will leave in a minute . [     ] A.for a minute B.a minute ago C.at once D.just now 2. We should take care not to caught or sneeze loud...
查看完整题目与答案
【单选题】Thousands of families killed and many children were left without parents.
A.
is
B.
are
C.
was
D.
were
查看完整题目与答案
【多选题】紧急避险必须具备以下哪些条件（）。
A.
必须是为了避免国家、公共利益、本人或者D他人的人身、财产和其他权利遇到危险而采取的
B.
必须是正在发生危险的情况下采取的
C.
必须是在不得已的情况下采取的，如果能采取其他方法避免危险，就不能实施紧急避险行为
D.
紧急避险行为不能超过必要的限度
查看完整题目与答案
【单选题】An American woman received a letter from a recently married Japanese friend. The Japanese woman wrote in her letter, "My husband is not very handsome. Your husband is much more handsome than mine." Th...
A.
She was trying to her American friend that she did not like her husband very much
B.
It is uncommon in Japan to compliment one's husband.
C.
She didn't think her husband was handsome, but she liked her personality.
查看完整题目与答案