问题
单项选择题
分馏系统停车退油过程中,当各塔随着退油而压力降低时,应()来控制压力
A、提高塔底温度
B、引入氢气增压
C、引入氮气增压
D、引入燃料气增压
答案
参考答案:C
分馏系统停车退油过程中,当各塔随着退油而压力降低时,应()来控制压力
A、提高塔底温度
B、引入氢气增压
C、引入氮气增压
D、引入燃料气增压
参考答案:C
A cold is a common illness. It often starts with a sore _1_.You sneeze and your nose runs. You usually _2_ a headache ,too ,It 's not a serious illness,but you can feel very_3_. what should you do when you have a cold?you should have a good rest,It is good __4_a lot of water too.You can __5_and take some medicine.Maybe you can try some Chinese medicine.Chinese medicine is now very__6____all over the world. Where does Chinese medicine __7_____?A long time ago, When people were not feeling__8____, they find that some plants could make them feel__9_____.They ate the leaves,the roots,the fruit,or the seeds of the plants. Today people make much Chinese medicine__10____those plants.
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