问题
单项选择题
以下各项关于液压支架阻尼回路说法不正确的是（）。
A、阻尼回路只能对进液起起节流作用。
B、阻尼回路可以使液压缸的动作较为平稳，可以使浮动状态下的液压缸具有一定的抗冲击负荷能力。
C、在液压支架中，阻尼回路多用于对调架千斤顶、推侧千斤顶或防倒千斤顶等的控制。
D、阻尼回路是在液压缸的工作支路上设置节流阀或节流孔而成。
答案
参考答案：A
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以下各项关于液压支架阻尼回路说法不正确的是（）。
A、阻尼回路只能对进液起起节流作用。
B、阻尼回路可以使液压缸的动作较为平稳，可以使浮动状态下的液压缸具有一定的抗冲击负荷能力。
C、在液压支架中，阻尼回路多用于对调架千斤顶、推侧千斤顶或防倒千斤顶等的控制。
D、阻尼回路是在液压缸的工作支路上设置节流阀或节流孔而成。
参考答案：A
“Sixteen,” I said. I have forgotten the math question my second-grade teacher, Joyce Cooper, asked that day, but I will never forget my 36 . As soon as the number left my mouth, the whole class started 37 . I felt like the 38 person in the world.. Mrs. Cooper fixed them with a firm look. Then she said: “We’re all here to 39 .” Once Mrs. Cooper asked us to write a 40 about what we hoped to do in the future. I wrote: “I want to be a 41 like Mrs. Cooper. She wrote on my report, “You would 42 an outstanding teacher 43 you are determined and you try hard.” I was to carry those 44 in my heart for the 27 years. After I graduated from high school, I got married and had children. We needed every penny just to 45 . College and teaching were out of the question. Then one day I thought of my 46 of how I wanted to help children. I talked it over with my family and 47 to attend college classes in the 48 before work. And when I got home from work, I would 49 . Finally, after seven years, my dream had been realized and I became a teacher. Not long after I started 50 , something happened that brought the 51 rushing back to me. I had written a sentence with grammatical errors on the blackboard. Then I asked students to come and 52 the mistakes. One girl got halfway through, became 53 and stopped. As the other children laughed, 54 rolled down her cheeks. I gave her a hug and told her to have a drink of water. Then, remembering Mrs. Cooper, I fixed 55 of the class with a firm look. “We are all here to learn,” I said.
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在一定体积的密闭容器中，进行反应CO2(g)+ H2(g) 
CO(g)+ H2O(g)。其平衡常数K和温度T的关系如表所示：
| T/℃ | 70 0 | 800 | 830 | 1000 | 1200 |
| K | 0.6 | 0.9 | 1.0 | 1.7 | 2.6 |
（1）该反应的化学平衡常数表达式为K=__________________
（2）该反应为______反应（填“吸热”或“放热”）
（3）能判断该反应达化学平衡状态的依据是____
A:容器中压强不变 B:混合气体中C(CO)不变
C:V(H2)正=V(H2O)逆 D:C(CO2)=C(CO)
（4）某温度下，平衡浓度符合下式：C(CO2) ·C(H2)=" C(CO)" ·C(H2O)试判断此时的温度__________________
（5）在800℃时，发生上述反应，某一时刻测得容器内各物质的浓度分别为C(CO2) 为2 mol/L ，C(H2)为1.5 mol/L ，C(CO) 为1mol/L， C(H2O)为3 mol/L，则此时刻反应向____（填“正向”或“逆向”）进行