问题 单项选择题 A1/A2型题

在前庭系统中感觉运动位置觉的解剖结构是()

A.壶腹嵴

B.椭圆囊斑

C.球囊斑

D.三个半规管

E.骨迷路

答案

参考答案:A

阅读理解

“Who has more questions, a teacher or a student?”About this question a great learned man told his students that nobody does but a teacher.

The students got puzzled. With a smile, the teacher drew the circles.“Within the larger one is my knowledge of things and within the smaller one is yours. Out of the circles is still unknown to both of us. Since mine is larger, as you can see, the line that marks out the circle is longer. That makes it clear that who has more chances to face something still unknown.”

小题1:The great learned man believed that          .

A.a teacher has more questions

B.a student has more questions

C.a teacher has no questions

D.a student has no questions小题2:The students thought that            

A.a student has fewer questions than his teacher

B.a teacher has more questions than a student

C.those who have less knowledge have more questions

D.those who have more knowledge have more questions小题3:At the end of the story, the greatest learned man made a conclusion that     .

A.a student should learn more from his teacher

B.a teacher should not have many question

C.a student knows much more than his teacher

D.a teacher has more chances to face unknown knowledge小题4:Which of the following titles is NOT suitable for the story?

A.You will Never Learn English

B.A Teacher and His Student

C.There Is No Limit to Knowledge

D.One Is Never Too Old to Learn小题5:We can often find such an article in        .

A.a guidebook to a museum

B.any kind of books

C.a newspaper or a magazine

D.an encyclopedia(百科全书)

单项选择题

阅读下面这篇文章,回答下列各题。

粒子束武器

粒子束武器大致分为三个主要部分,即由能源、电子喷嘴和集流加速器组成。

能源,一般是靠核裂变或聚变的极高的脉冲功率形成。人们采用专门的核爆炸式的发电机,通过核裂变或聚变释放出大量的能量,发出高压脉冲电流。它通过控制开关和特殊传输线路在一瞬间传输给巨型贮能器,把脉冲电荷堆积起来,通过超高压开关在毫微秒计的时间内放电。

流量压缩装置和电子注入器把脉冲高压转换成电子束,高强电磁场把它在长长的电子枪中加速,通过电子嘴向集流加速器喷射,作为形成和加速质子的媒介。

集流加速器是粒子束的核心。在电子喷嘴和集流加速器之间,装有注入阀,引入Z质(如有一种加速器的Z质用氢气),由于电子束的高速碰撞,电子被剥落,形成质子,并集流加速,最后接近光速发射出来,摧毁目标。

粒子束武器的简单工作过程是:通过核裂变或聚变的形式实现爆炸或脉冲发电,以产生高功率的脉冲粒子束,这些粒子束以接近光速的速度射向目标,击毁目标。

(选自《自然科学》14辑)

在粒子束形成的过程中,经历了多次转换。这些转换的物质依次是()。

A.脉冲高电压——电子表——高强电磁场——质子束

B.脉冲高电压——电子表——Z质——粒子束

C.脉冲电荷——电子束——媒介——质子束

D.高压脉冲电流——电子束——质子束