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问题 选择题

下列实验操作正确的是（　　）

A．手持试管给试管里的物质加热

B．用燃着的酒精灯去点燃另一个酒精灯

C．用天平称量药品时，用手直接拿取砝码

D．用滴管滴加液体时，滴管不能触及容器内壁

答案

A、应用试管夹或将试管固定在铁架台上给试管里的物质加热，故选项说法错误；

B、禁止用一酒精灯去引燃另一酒精灯，否则会引发火灾，故选项说法错误；

C、取用砝码要用镊子，用手取用砝码会使砝码生锈，造成以后称量不准确；胡选项说法错误；

D、滴加试剂时，滴管要保持垂直悬于容器口上方；胶头滴管使用时不能伸入容器中或与器壁接触，否则会造成试剂污染．故选项说法正确．

故选D．

完形填空

语法填空（共10小题，每小题1.5分，满分15分）

阅读下面短文，根据上下文填入适当的词语，或使用括号中的词语的适当形式填空。

Chinese President Hu said before arriving in Pittsburgh ahead of the G20 summit, “To realize __1__ safer world for all, we must first and foremost remove the threat of nuclear war,” saying Beijing has always wanted complete __2___ (prohibit) and thorough destruction of nuclear weapons. Hu also said, “All countries should join the NPT (Nuclear Nonproliferation Treaty) and make real efforts to uphold and enhance its authority and __3__ (effective).” It was the third day when Hu had made a major speech before world leaders. __4__ was the first time that he __5__ (address) such a high-level summit on disarmament(解除武装) and nonproliferation(消除核扩散). Hu made five proposals in his speech, _6__ (say) all countries with nuclear weapons should publicly commit to not wanting to possess _7__ in the long term. Hu said China will consistently support nonproliferation and disarmament treaties. “We have adhered to(坚持) the policy of no-first-use of nuclear weapons at any time and __8__ any circumstance, and made the commitment that we will unconditionally not use or threaten to use nuclear weapons _9__ non-nuclear-weapon states or nuclear-weapon-free zones,” said Hu. The Chinese president said the function of the International Atomic Energy Agency should __10__ (strength).
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问答题 简答题

存在所谓的敢死队，突击队么？他们是去手工插入控制棒么？可有报道说地震时已经自动完成了反应堆的关闭，只是目前余温过高。还是他们只是在注水注降温剂？
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