问题
问答题 简答题
丁二烯过氧化物有何危险？
答案
参考答案：
丁二烯过氧化物是在适宜的温度、压力和氧等条件下生成的，它很不稳定，在受热时、受撞击、遇空气时极易分解而产生高温高压并引起燃烧爆炸，因此它的存在给安全生产带来了极大危胁。
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丁二烯过氧化物有何危险？
参考答案：
丁二烯过氧化物是在适宜的温度、压力和氧等条件下生成的，它很不稳定，在受热时、受撞击、遇空气时极易分解而产生高温高压并引起燃烧爆炸，因此它的存在给安全生产带来了极大危胁。
完形填空（共20小题；每小题1.5分，满分30分） 阅读下面短文，从短文后各题所给的四个选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该项涂黑。 Sometimes we need to remind ourselves that thankfulness is indeed a virtue. —William Bennett Thanksgiving Day was near. The first grade teacher gave her class a fun __36__ to draw a picture of something for which they were thankful. Most of the class might be considered economically __37__, but still many would __38__ the holidays with turkeys and other traditional goodies of the season. These, the teacher thought, would be the __39__ of most of her students’ art. And they were. __40__, Douglas made a different kind of picture. Douglas was a special kind of boy. He was the teacher’s true child of misery, __41__ and unhappy. As other children played at break, Douglas was likely to stand close by her side. One could only guess the pain Douglas felt __42__ those sad eyes. Yes, his picture was different. When __43__ to draw a picture of something for which he was thankful, he drew a hand. Nothing else. Just a(n) __44__ hand. His abstract image captured the __45__ of his classmates, whose hand could it be? One child guessed it was the hand of a farmer, because farmers __46__ turkeys. Another suggested a police officer, because the police protect and __47__ people. And so the discussion went ---- until the teacher __48__ forgot the young artist himself. When the children had gone on to other tasks, she __49__ at Douglas’ desk, bent down, and asked him whose hand it was. The little boy looked away and __50__, “It’s yours, teacher.” She __51__ the times she had taken his hand and walked with him here and there, __52__ she had other student. How often had she said, “Take your hand, Douglas, we’ll go outside.” Or, “Let me show you how to hold your pencil.” Or, “Let’s do this together.” Douglas was most thankful for his teacher’s hand. Brushing __53__ a tear, she went on with her work. The story speaks of __54__ thankfulness. It says something about teachers teaching and parents parenting and friends showing friendship, and how much it means to the Douglases of the world. They might not always say thanks, but they’ll remember the hand that __55__.
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