题干

下列核反应方程及其表述中错误的是(   )

A:1124 Na→ 1224 Mg+ 10 e是原子核的β衰变

B:23 He+ 12 H→ 24 He+ 11 H是原子核的α衰变

C:24 He+ 1327 Al→ 1530 P+ 01 n 是原子核的人工转变

D:92235 U+ 01 n→ 3692 Kr+ 56141 Ba+3 01 n是重核的裂变反应

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答案(点此获取答案解析)

B

同类题1

阅读理解

    One fine afternoon I was walking along Fifth Avenue when I remembered that it was necessary to buy a pair of socks. I turned into the first sock shop that caught my eye, and a boy clerk who could not have been more than 17 years old came forward.

    “What can I do for you, sir?”

    “I wish to buy a pair of socks.”

    His eyes glowed. “Did you know that you had come into the best place in the world to buy socks?” I had not been aware of that.

    “Come with me,” said the boy happily. He began to haul (用力拖) down from the shelves box after box.

    “Hold on, boy, I am going to buy only one pair!”

    “I know that,” said he, “but I want you to see how beautiful these are. Aren't they wonderful?” There was on his face an expression of joy, as if he were showing to me the mysteries of his religion.

    “My friend,” said I, “if this is not just the enthusiasm (热情) that comes from novelty (新鲜), if you can keep up this day after day, in ten years you will own every sock in the United States.”

    In many shops the customer has to wait for someone to serve him. And when finally some clerk does notice you, you are made to feel as if you were disturbing him. He displays no interest either in you or in the goods he is paid to sell.

    Yet possibly that very clerk who is now so cold began his career with enthusiasm. As time goes by, the enthusiasm is gradually gone; his only pleasures were found outside of working hours. He became a mechanical (机械的), not inspired, salesman.

    I have observed such change in the lives of so many people in so many occupations that I have come to the conclusion that the fastest road to failure is to do things mechanically.

同类题5

阅读下面的文字,完成小题。

    两千多年前司马迁著《史记》,对孔子钦慕之情切切。又似有丝丝缕缕弦外之音,好像司马氏不仅找到了精神家园,还体悟到了更高境界的史家情怀。

    然而将至圣先师名为史家,古今鲜有人为。当然,孔子称得上是一位了不起的史学家,尽管他没做过一天的史官。班固《汉书·艺文志》说:“古之王者世有史官……左史记言,右史记事,事为《春秋》,言为《尚书》。”依班固言推论,《春秋》当为鲁国右史所为。而孔子年轻时做过委吏、职司吏,后任中都宰,三年骤迁大司寇摄相事,唯不见其做史官的记录。

    言史家孔子,也实不虚妄。读万卷书,孔子自不待说,孔子于周史应是详熟,行万里路孔子也是不输,少时“入太庙,每事问”,壮而适周问礼,又周游列国十四载,孔子该是家事国事天下事事事周详。其外,孔子于人物也察考洞明,当是有资格论人议事了。孔子的历史观与著述态度在今看来也十分可取,对待历史所持科学严谨的态度胜过今人。此大可辅言孔子为史家了。

    但是,以《春秋》名孔子为史家似乎也有点勉强。首先,孔子著《春秋》一事实有争议。《春秋》是鲁国史书,历来被认为是鲁国史官所为;可历代史家、学者又以为是孔子所修,《左传·成公十四年》载“君子曰:《春秋》……非圣人谁能修之”。“圣人”就定指孔子吗?所以,这里不足为明证。倒是孟子言之凿凿:“世道衰微,邪说暴行有作……孔子惧,作《春秋》。”算是敲定此事。孟子齐人,距孔子百多年,近圣人之居,史料当丰,传闻即真,况孟轲崇信求义,可信度应是很高。再有《史记·十二诸侯年表》道:“是以孔子明王道,干七十余君,莫能用,故西观周室,论史记旧闻,兴于鲁而次《春秋》。”大抵也能杜左右之口。当然也有折中的说法。两边都讨好,各方不得罪:《春秋》原为鲁国史官所写,后经孔子修订成书。虽万分稳妥,可如此一来,孔子有假他人之功的嫌疑。

    还有一个问题,《春秋》一万六千字,在今不抵一篇硕士论文的篇幅,可却微言大义,辞微旨博,一字褒贬,影响深远。于是历代解“经”传“经”之作不乏。单说用古文写就的《春秋左氏传》,其史料补充丰赡,记事因果清明,写人性格丰满,使《春秋》史纲泱泱为一部有历史律动的不朽巨作,堪称伟大。然而左丘明因《左传》称史家,而孔子有《春秋》却不称史家,这很值得深思。

    所以,言孔子为史家实不足取。孔子只是“好古”。自称“述而不作”,只阐述前人学说而不去创作;“祖述尧舜,宪章文武”,旨在缔造理想,“大同”“小康”。孔子又不只是好古,世衰道微,礼崩乐坏,孔子批判,毫不隐晦。虽“干七十余君,莫能用”以致“累累如丧家之犬”,仍卓然独立,岁寒松柏,代王立法,惩恶劝善。如此说来,称孔子为史家还真的格局太小。夫子“木铎”,不若称“春秋”孔子。

(选自郭小琲《<春秋>有大义》,有删改)