题干

2012年1月,广西龙江河发生镉(Cd)污染事件,造成柳江上游非饮用水保护河段轻度污染.元素符号“Cd”不能表示(    )

A:镉元素

B:金属镉

C:一个镉原子

D:一个镉分子

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答案(点此获取答案解析)

D

同类题1

根据短文理解,选择正确答案。

    Five years ago, David Smith wore an expensive suit to work every day. “I was a clothes addict(有瘾的人),” he jokes. “I used to carry a fresh suit to work with me, so I could change if my clothes got wrinkled(有褶皱的).” Today David wears casual clothes (便装) to the office. He hardly ever wears a necktie. “I am working harder than ever.” David says, “and I need to feel comfortable.”

    More and more companies are allowing their office workers to wear casual clothes to work. In the United States, the change from formal to casual office wear has been gradual. In the early 1990s, many companies allowed their employees to wear casual clothes on Friday. This became known as “casual Friday”. “What started out as an extra one-day-a-week benefit for employees has really become an everyday thing.” said business consultant Maisly Jones.

    Why have so many companies started allowing their employees to wear casual clothes? “One reason is that it's easier for a company to attract new employees if it has a casual dress code.” “A lot of young people don't want to dress up for work,” says Owen Black, the owner of a software company, “so it's hard to hire people if you have a conservative (保守的) dress code.” Another reason is that people seem happier and more productive when they are wearing comfortable clothes. In a study conducted by Levi Company, 85 percent of employers said that they believe that casual dress improves employee morale (心境, 士气). Only 4 percent of employers said that casual dress has a negative influence on productivity. Supporters of casual office wear also argue that a casual dress code helps them save money. “Suits are expensive, if you have to wear one every day,” one person said. “For the same amount of money, you can buy a lot more casual clothes.”

同类题3

阅读下面的文言文,完成后面小题。

    赵咨字文楚,东郡燕人也。父畅,为博士。咨少孤,有孝行,州郡召举孝廉,并不就。延熹元年,大司农陈奇举咨至孝有道,仍迁博士。灵帝初,太傅陈蕃、大将军窦武为宦官所诛,咨乃谢病去。太尉赐特辟,使饰巾出入,请与讲议。举高地,累迁敦煌太守。以病免还,躬率子孙耕农为养。盗尝夜往劫之,咨恐母惊惧,乃先至门迎盗,因请为设依,谢曰:“老母八十,疾病须养,居贫,朝夕无储,乞少置衣粮。”妻子物余,一无所请。盗皆惨叹,跪而辞曰:“所犯无状,干暴贤者。”言毕奔出,咨追以物与之,不及。由此益知名。征拜议郎,辞疾不到,诏书切让,州郡以礼发遣,前后再三,不得已应召。复拜东海相。之官,道经荥阳,敦煌曹暠,咨之故孝廉也,迎路谒候,咨不为留。暠送至亭次,望尘不及,谓主簿曰:“赵君名重,今过界不见,必为天下笑!”即弃印绶,追之东海。谒咨毕,辞归家。其为时人所贵若此。咨在官清简,计日受奉,豪党畏其俭节。视事三年,以疾自乞,征拜议郎。抗疾京师,将终,告其故吏朱祗、萧建等,使薄殓素棺,籍以黄壤,欲令速朽,早归后土,不听子孙改之。朱祗、萧建送丧到家,子胤不忍父体与土交合,欲更改殡,祗、建譬以顾命,于是奉行,时称咨明达。

(《后汉书·赵咨传》有删节)

同类题5

阅读下文,回答问题

鞭王

贺敬涛

    ①鞭王姓赵名四,身长不足五尺,精瘦,肤黑。

    ②赵四自幼家贫,两岁丧父,七岁丧母,尝尽人间辛酸。

    ③12岁那年腊月三十,天降大雪,年幼的赵四在东桑庄李员外家,讨得了两块玉米馍馍和一碗白菜粉条汤,一路小心翼翼往栖身的关公庙赶,上台阶时被地上一物几乎绊倒,定睛看时,是个羸弱潦倒的老头,单薄的破帽破袄破裤,在呼啸的北风中缩成一团,怀里却紧抱个黑布包裹的细长物件,用手一探,身有余温,赵四急忙将老人抱至庙内,生起火,将馍馍饭菜重新热了来喂老人,老人不说话,一把抢过去,狼吞虎咽吃了馍馍,喝尽了汤,吧咋吧咋嘴,倒头就睡。

    ④第二天,赵四出去讨饭,回来将讨的饭送给老人,老人亦不说话,仍是吃了就睡。

    ⑤雪,下了又化,年,来了又走,一晃正月就这样飘走了。

    ⑥一个早晨,天刚麻麻亮,赵四被老人从睡梦中拉起,见老人斜夹了包裹,老人不说话,只是拉了赵四,疾走至庙后松林空地,“噗”地抖开包裹,眼前竟亮出一杆奇特大鞭,老人这才道出了自己身份,并将一身绝活传给了赵四。

    ⑦那赵四天资聪慧,加之悟性又高,遂练得一身使鞭绝活,鞭梢过处,多少烈马亦乖巧老实,名震数十里。

    ⑧绝的是那杆鞭,鞭杆长七尺,全用生牛皮条丝丝绕就,鞭长一丈五,一丈二处有九个扣结,内有九枚铅块,名唤九珠连环,鞭梢一尺为狗皮割成。

    ⑨这杆鞭不懂门的即使身长体阔,依然打它不开。

    ⑩更绝的是“金龙三点头”,赵四站定,运气抖鞭,每走一步,会快速打出一鞭,而每一鞭打出,鞭出一声,抽回一响,落地又一响,真真奇绝。

    ⑪卢沟桥事变的第二年,豫西沙河镇上驻扎一队日本兵,队长山本有三好,一马二色三杀人,多少无辜中国人被打个半死,用绳子捆了,拴在马后活活拖死,多少姑娘被摧残。

    ⑫这一日,山本又从别处弄来一匹烈马,马身长丈二,体高六尺,浑身雪白无半根杂毛,真是一匹好马,怎奈马没有驯,又踢又咬,没人敢近身。有狗子就把鞭王推荐给了山本,山本给赵四下了一帖,限三日到日本兵驻地,第四日不到,就要血洗沙河镇,不想,赵四一口应下。

    ⑬第三日,太阳初升之时,赵四已怀抱大鞭悄然立在山本养马大院。

    ⑭那马一见有人来,吸溜溜一声咆哮,四蹄腾空向赵四扑来,赵四闪身避过,旋即退到后院,那马扑了个空,拧身再扑,“叭”,赵四出手一鞭,这鞭法极其讲究,系用九珠连环下两环打马眼眶上两耳中下一穴道,马扑通卧倒。

    ⑮那马不服,打个响鼻,腾空再扑,但见赵四身轻如燕,耳听得声声脆响,马扑通一声四腿跪地,浑身哆嗦不止,赵四则稳稳落地,无声无息,鞭身亦轻盈收回绕到鞭杆上。赵四抛出四块灰砖,喝令马立在上面,马竟不敢动半步。

    ⑯山本早已惊呆许久,醒过神来,竖起大拇指,笑眯眯地来拍赵四的肩:“吆——西!”

    ⑰赵四显出惊恐状,低着头,愣愣的,用手在自己脖子上比了一下,接着浑身发抖起来。

    ⑱山本哈哈大笑:“杀头的没有,留下马倌的干活!”

    ⑲赵四竟笑呵呵地点了头。

    ⑳五日后,经赵四细驯,那马竟能通人性懂人语,跳跃腾挪矫健非常,山本每天爱不释手,骑个没够。

    ㉑这一日,山本带了一卫兵骑马去沙河镇炮楼巡查工事,骑在马背上得意扬扬,好不威风。

    ㉒沙河道里,茅草、芦苇有一人多高,森森立着。

    ㉓猛听得半空中一声哨响,那马忽地跳起,咚!把山本掀翻鞍下,山本一只脚被套在马镫上。又一声哨响,那马飞奔起来,路上乱石、树桩像把把重锤、尖刀,撞击、剐蹭,转眼间山本已肚破尸裂,卫兵提马来追,那马背上早已端坐一人,怀抱一杆大鞭,正是赵四。

    ㉔卫兵举枪瞄准,不料凌空飞来一鞭,鞭身绕着卫兵,鞭梢则缠住了枪托,赵四猛一抽鞭,人借马势,枪冲天放了一炮后,飞到了空中,鬼子兵亦被凌空抛出三丈远,落地当即气绝。

    ㉕赵四哈哈大笑,提马疾驰而去。

(选自《小小说选刊》2017年第1期)