分析牛头刨床和插床在结构和工艺范围方面的主要区别。

氮是大气中含量丰富的一种元素，氮及其化合物在生产、生活中有着重要作用，减少氮氧化物的排放是环境保护的重要内容之一。请回答下列氮及其化合物的相关问题：

(1)据报道，意大利科学家获得了极具研究价值的N₄，其分子结构与白磷分子的正四面体结构相似。已知断裂1 mol N－N键吸收167 kJ热量，生成1 mol N≡N键放出942 kJ热量，请写出N₄气体转变为N₂反应的热化学方程式：                            。

(2)据报道，NH₃可直接用作车用燃料电池，写出该电池的负极反应式：                          。

(3)在T₁℃时，将5 mol N₂O₅置于10L固定容积的密闭容器中发生下列反应：2N₂O₅(g)4NO₂(g)+O₂(g)；△H＞0。反应至5分钟时各物质的浓度不再发生变化，测得NO₂的体积分数为50%。

①求该反应的平衡常数K=        (数字代入式子即可)，上述平衡体系中O₂的体积分数为__________。

②用O₂表示从0～5 min内该反应的平均速率υ(O₂)=        。

③将上述平衡体系的温度降至T₂℃，密闭容器内减小的物理量有        。

A．压强           B．密度          C．反应速率          D．N₂O₅的浓度

(4)在恒温恒容的密闭容器中充入NO₂，建立如下平衡：2NO₂(g)N₂O₄(g)，平衡时N₂O₄与NO₂的物质的量之比为a，其它条件不变的情况下，分别再充入NO₂和再充入N₂O₄，平衡后引起的变化正确的是__________。

A．都引起a减小   B．都引起a增大   C．充入NO₂引起a减小，充入N₂O₄引起a增大

D．充入NO₂引起a增大，充入N₂O₄引起a减小

Daniel's family      their holiday in Huangshan this time next week.

A．are enjoying

B．are to enjoy

C．will enjoy

D．will be enjoying

A warm blanket is the ideal sleep aid for a freezing winter night. The right blanket can warm your bones but the wrong one can affect your sleep. I asked experts for advice on picking the perfect blanket for a good night’s sleep. Here’s what they told me.

When it comes to sleep temperature, experts recommend following the principle: not too cold, not too hot, but just right. “People seem to sleep best at temperature between 62 and 70 degrees F,” says Dr. Alice Hoagland. When the surrounding temperature falls too low, it can rouse you from sleep. A good blanket helps drive the coldness away.

At the other extreme, overheating yourself can affect your sleep as well. “Core body temperature typically drops during the first four hour’s of sleep,” says Dr. Hoagland. This decline in body temperature helps you fall asleep and stay asleep.

“In medical care, weighted blankets are one of our most powerful tools for helping people who are anxious, upset, and possibly losing control,” says Dr. Karen Moore. These special blankets are filled with weighted pellets. Weighted blankets are also marketed for general use as an aid to sleep and relaxation. Like a firm hug, weighted blankets help us feel safe.” This is the reason why many people like to sleep under a blanket even in summer.

“If you want to try this type of blanket, the best weight depends on your body size and personal preference. However, 15 to 30 pounds is typical for adults,” Moor says. She adds that weighted blankets are not recommended for those recovering from surgery.

“People can also have serious preferences for a particular blanket,” says Dr. Hoagland. “Regularly using a favorite blanket for sleep can help to develop a conditioned response so that sleep is quicker.” In fact, many sleep centers ask patients to bring their own blanket and pillow from home, which helps them fall asleep more easily.

小题1:The author wrote the passage mainly to tell us _____.

A．the importance of blankets

B．how to choose the perfect blanket

C．different materials used to make blankets

D．the history and usage of blankets小题2:The underlined word “rouse” in Paragraph 2 is the closest in meaning to “______”.

A．wake up

B．take up

C．make up

D．pick up小题3:What do we know from the passage?

A．Body temperature rises when we fall asleep

B．The perfect sleep temperature should be above 70 degrees F.

C．Weighted blankets should be at least 30 pounds.

D．People are advised to use their own blankets.

考虑到毒物扩散的危险性，危险物质分类中将( )定义为第8种危险物质。

A．有毒品

B．有害品

C．毒性物质

D．剧毒品

国家对新药审批时的检验属于（）

A.抽查检验

B.注册检验

C.指定检验

D.委托检验