某同学将力传感器固定在小车上，然后把绳的一端固定在传感器的挂钩上，用来测量绳对小车的拉力，探究在小车及传感器总质量不变时加速度跟它们所受拉力的关系，根据所测数据在坐标系中作出了如图所示的a－F图象。

Ⅰ纳米级Cu₂O的用途研究

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①氨气是一种有刺激性气味的气体，在高浓度氧气中才能燃烧，生成氮气和水．

②在纳米级Cu₂O的催化作用下，氨气与氧气在一定温度下发生以下化学反应：

4NH₃+5O₂═4NO+6H₂O         4NH₃+3O₂═2N₂+6H₂O

工业上用NO制备硝酸、氮肥等化工产品．

对藻类的水华生物生长繁殖产生影响。据新华社合肥8月10日电，安徽省巢湖市饮用水源地周边连日来出现明显蓝藻集聚。安徽省环保厅已两次发出蓝藻水华红色预警，这引发了公众对于饮用水安全的担忧。

分析7、8月份巢湖“水华”现象严重的原因。

Edward and William are brothers. There is      uncommon similarity between       two boys.

完形填空题

     My family members like to use computers. We live in China. My aunt1in Australia. My mother and my aunt often2e-mails to each other. Sometimes3chat(聊天) online.

     My father is a4in a middle school. He often searches for5for his lessons6the Internet.

     My brother and I like to7computer games. I like to play Counter Strike, but he likes to play Seer(赛尔号). My8don't like us to play them too long. They say that playing computer games too long is bad for our9and study. We both like music, too. So sometimes we10music on the computer.