下列哪种室性心动过速不宜使用直流电复律治疗A．持续性室性心动过速 B．特发行室性心动

有一普通完全井，其直径为0.5m，含水层厚度H=10m，土壤渗透系数k=2.5m/h，抽水稳定后的井中水深h=7m，试估算井的出水量为( )。

A．(A) 16mL/s

B．(B) 18L/s

C．(C) 20L/s

D．(D) 24L/s

高纯MnCO₃是制备高性能磁性材料的主要原料。实验室以MnO₂为原料制备少量高纯MnCO₃的操作步骤如下：

（1）制备MnSO₄溶液：在烧瓶中（装置见上图） 加入一定量MnO₂和水，搅拌，通人SO₂和N₂混合气体，反应3h。停止通入SO₂，继续反应片刻，过滤(已知MnO₂+ H₂SO₃= MnSO₄ +H₂O)。

①石灰乳参与反应的化学方程式为__________________________________

② 反应过程中，为使SO₂尽可能转化完全，在通人SO₂和N₂比例一定、不改变固液投料的条件下，可采取的合理措施有_______________________________

③若实验中将N₂换成空气，测得反应液中Mn²⁺、SO₄^2-的浓度随反应时间t变化如上图。导致溶液中Mn²⁺、SO₄^2-的浓度变化产生明显差异的原因是_________________________

（2）制备高纯MnCO₃固体：已知MnCO₃难溶于水、乙醇，潮湿时易被空气氧化，100℃开始分解；Mn(OH)₂开始沉淀的pH= 7.7。请补充由(1) 制得的MnSO₄溶液制备高纯MnCO₃的操作步骤[实验中可选用的试剂：Ca(OH)₂、NaHCO₃、Na₂CO₃、C₂H₅OH]。

①_______________________________________；

②_______________________________________；

③________________________________________；

④_______________________________________；

⑤低于100℃干燥。

在举重比赛时，一运动员在第一阶段把150kg的杠铃很快举过头顶；第二阶段使杠铃在空中停留3s．下列关于运动员对杠铃做功的说法．正确的是（   ）．

A．他在第一阶段内没做功

B．他在第二阶段内没做功

C．他在两个阶段内都没做功

D．他在两个阶段内都做了功

Any serious policy discussion about acceptable levels of risk in connection with explosions is not well served if the participants fail to use the word "explosion" and use the phrase "energetic disassembly" instead. In fact, the word "explosion" elicits desirable reactions, such as a heightened level of attention, whereas the substitute phrase does not. Therefore, of the two terms, "explosion" is the one that should be used throughout discussions of this tort.
Which of the following is an assumption on which the argument above depends

A．In the kind of discussion at issue, the advantages of desirable reactions to the term "explosion" outweigh the drawbacks, if any, arising from undesirable reactions to that term.

B．The phrase "energetic disassembly" has not so far been used as a substitute for the word "explosion" in the kind of discussion at issue.

C．In any serious policy discussion, what is said by the participants is more important than how it is put into words.

D．The only reason that people would have for using "energetic disassembly" in place of "explosion" is to render impossible any serious policy discussion concerning explosions.

E．(E) The phrase "energetic disassembly" is not necessarily out of place in describing a controlled rather than an accidental explosion.

关于呼气末二氧化碳分压监测的叙述，哪项不正确：（）

A.二氧化碳分压的监测结果可以替代血气分析测得的结果

B.如果检测时间较长时，需要重新调定零点

C.如果二氧化碳监测窗中有泠凝水，会影响监测结果的准确性

D.现二氧化碳分压的监测方法多采用旁流型

E.行二氧化碳分压监测前需要先调零点