加氢装置停工时装置进行轻质馏份油置换可以避免低温下重质原料油中结焦前驱物大量沉积在催化剂表面,否则重新开工时容易致使催化剂结焦失活。
参考答案:对
完成对话。
Lucy: Hi! Jim
Jim: Hi! Lucy. You know Li Ming is1. soon. So we'll have a 2. for him to
3. goodbye.
Lucy: Great.
Jim: Would you like to 4. to the party?
Lucy: Yes, I would. When will the party 5. ?
Jim: 6. 4:00 tomorrow afternoon
Lucy: Does Li Ming know about it?
Jim: No, we want 7. a 8. party for him.
Lucy: Really? Then I will not 9. him about it.
Jim: Good! Could you come 10. to help us?
Lucy: Sure.
1998年暑假,某班10位同学在海鲜馆聚餐,吃完海产品2小时后,陆续有8位同学出现呕吐、腹痛、频繁腹泻,腹泻一般为水样、血水样、粘液或脓血样便,里急后重不明显。部分患者发冷、发热,重症者出现脱水,少数有意识不清、血压下降、循环障碍。第3天后中毒症状逐渐好转,此次食物中毒最可能是
A.河豚毒素中毒
B.沙门菌属中毒
C.副溶血性弧菌中毒
D.麻痹性贝类中毒
E.变形杆菌中毒