题干

关于电源,下列说法正确的是     

A:电源是储存电能的装置

B:电源是储存电荷的装置

C:电源是将化学能转化为电能的装置

D:电源是将其它形式的能转化为电能的装置

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答案(点此获取答案解析)

D

同类题2

阅读下面的文字,完成下列各题。

刘节:史家风骨士子魂

    20世纪50年代以后的中山大学历史系,以名流云集著称,陈寅恪地位最尊,自不待言。陈又与岑仲勉并称“二老”,加上刘节、梁方仲,则号称“四大教授”。刘节一度担任历史系主任,中山大学历史系在当时堪称岭南史学界的一大“重镇”。

    1926年,刘节考入清华国学研究院,师从王国维、梁启超和陈寅恪,专攻中国哲学史。清华国学研究院同学王力对刘节的印象和评价:“君待人无贵贱,一接以礼。视友事若己事,蔼然似长者。”

    在整个中国学术界,刘节与陈寅恪的师生情谊广为人知。据中山大学历史系老师回忆,逢年过节,刘节去拜望陈寅恪时,必对老师行下跪叩头大礼,一丝不苟,旁若无人。刘节还曾对学生说:“你们想学到知识,就应当建立师生的信仰。”但这句话在当时被当作罪证受到学生猛烈批判。1952年到1969年,在送恩师陈寅恪最后一程的陈门弟子中,长期陪伴老师左右的,唯独刘节一人。他是在任何压力下都绝不批陈的学生,义无反顾地与恩师同甘共苦,其自身所受苦难之深重已达无以复加之地,却还经常主动把老师要受的苦难都揽到自己头上。1967年底,红卫兵要抬陈寅恪教授去大礼堂批斗,陈夫人出面阻止,被造反派狠狠推倒在地。刘节挺身而出,代替老师去挨斗。批斗会上,“小将”们对刘节轮番辱骂、殴打,之后又问他有何感想,刘节昂起头回答:“我能代替老师挨批斗,感到很光荣!”

    抗日烽火绵延,家国罹难,导致学人不能安于讲席,经受乱离流浪之苦,刘节可谓体验得真切。从《刘节日记》中可以看出,尽管背井离乡,生活条件恶劣,要靠中英庚款的研究经费资助才得以勉强度日,他却安贫乐道,始终保持着一种乐观的心态,以治学和研究为乐。

    在治学上他主张求真、自信。他说,“考据学是求真之学”,“历史学家要有很强的自信力,一个历史学家要坚定不移,不要为一时的风浪而动摇不定”。

    在“文革”期间,刘节先后遭受60多场批判,受到戴高帽、剃光头、被抄家、遭殴打、罚劳改等等非人待遇,在人生最艰难的时期,刘节仍写下这样掷地有声的话:“人格同学问是一致的,决没有学问好而人格有亏的伟人。”表示“假定有一种势力要打破我的信仰,使我不能安静为学,我当然要抵抗……设若有一种势力要阻碍我的志向,使我不能如愿以偿,我当然要拿出毅力来”。

    面对这类政治运动,现存的《刘节日记》没有留下这一时期的直接记录,但读书的人自能感受到他是以平常心、宽恕心处之的。这有一个旁证,据其学生姜伯勤后来回忆,作为“白专”学生的典型,他也参与批判了刘节唯心主义史学,但1959年本科毕业时,刘节却向学校的党委领导表示:“你们要把姜某留下来,这个人能成器。”这既可见刘节的眼光,也可见其胸襟。

    刘节对子女的教育一贯民主、宽容,据刘节的儿子刘显曾回忆,“我感觉他对我们兄弟俩是慈爱而不溺爱,严格而不严厉”。在他看来,虽然父亲可以说“孔子的门徒”,但回想起来,父亲对儿子、妻子都是很平等、民主的。“他从来不说重话,可以说对儿子亦子亦友、对我母亲亦妻亦友”。在刘显曾20岁生日时,父亲对其说“感情要专一”。当时刘显曾正在上高中,当天他亲自来学校要儿子回家过生日,“在他看来这是我的成年礼了,所以要告诉我这个重要原则。

【相关链接】刘节,近代中国著名历史学家,著述颇丰。在研究先秦古史、先秦诸子思想、史学史方面有卓著成就,为了不被古代多种传说迷惑,他通过对古代文字的钻研去发现古史的真实材料。他多年开设史料学和史学史课程,著有《中国史学史稿》,这本书对历代修史制度、史籍之宏富多样和著名史家的成就均有翔实的论述,见解独到,尤其重视历史哲学的发展,是中国史学史学科重要代表作之一,著名史学家白寿彝称誉本书为“必传之作”。

同类题3

阅读理解

Bicycle Safety

    Operation Always ride your bike in a safe, controlled manner on campus(校园). Obey rules and regulations. Watch out for walkers and other bicyclists, and always use your lights in dark conditions.

    Theft Prevention Always securely lock your bicycle to a bicycle rack — even if you are only away for a minute. Register your bike with the University Department of Public Safety. It's fast, easy, and free. Registration permanently records your serial number, which is useful in the possible recovery of the bike stolen.

Equipment

    Brakes Make sure that they are in good working order and     adjusted properly.

    Helmet A necessity, make sure your helmet meets current safety standards and fits properly.

    Lights Always have a front headlight — visible at least 500 feet in front of the bike. A taillight is a good idea.

Rules of the Road

    Riding on Campus As a bicycle rider, you have a responsibility to ride only on streets and posted bicycle paths. Riding on sidewalks or other walkways can lead to a fine. The speed limit for bicycles on campus is 15 mph, unless otherwise posted. Always give the right of way to walkers. If you are involved in an accident, you are required to offer appropriate aid, call the Department of Public Safety and remain at the scene until the officer lets you go.

    Bicycle Parking Only park in areas reserved for bikes. Trees, handrails, hallways, and sign posts are not for bicycle parking, and parking in such spots can result in a fine.

If Things Go Wrong

    If you break the rules, you will be fined. Besides violating rules while riding bicycles on campus, you could be fined for:

No bicycle registration  ………………..……………….…… $25

Bicycle parking banned   …………..…………………….……$30

Blocking path with bicycle   …………………………….……$40

Violation of bicycle equipment requirement  ……………....…$35

根据短文内容,选择最佳答案,并将选定答案的字母标号填在题前括号内。

同类题4

阅读下面短文,从各题所给的A、B、C、D四个选项中选出最佳选项。
C
    It was Sunday. Henry did some shopping and then went to the car park. It was about to start the car when a robber stood up from the back seal. He held a knife to Henry's bead. "Give mc your wallet and drive me to North Street!" he shouted.
    "All right," Henry answered. Then he started the car and drove away. Being 72 years old, be knew he could not fight the young robber. He knew he needed help. Where were the police? As he drove towards each crossing, he looked up and down the side streets, hoping to meet a police car. But he could see none. "Just my luck," he thought. "If I was driving too fast, there would be a police car on every corner."
    So he pushed his foot down on the accelerator (油门), and the car ran much faster. "What are you doing?" shouted the robber. "Keeping off the police," Henry answered. "I thought I saw a police car back there."
    He ran red lights, drove the wrong way on one-way streets. On two way streets he drove on the wrong side of the road. Not one policeman saw him. Again Henry's plan was not working. He had to try a new plan.
    He turned a corner and saw the police station in front. Then he drove his car as fast as he could towards the police gate. The car hit a police motorbike down and stopped. Henry shouted, "Help! Help!" Then he turned back to grab the man's knife. At the same time the policemen heard the shout and quickly caught the robber.