题干

以油类为溶剂的防锈漆为油基防锈漆,由于环保方面的原因,目前要推广使用水基防锈漆,但水基漆较易溶解O2,在干燥之前导致金属表面产生锈斑,为此要在水基漆中加入缓蚀剂以除去氧气,以一可作为缓蚀剂的是

A:KMnO4

B:NaNO2

C:FeCl3

D:NO3

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答案(点此获取答案解析)

B

同类题4

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槭树下的家

席慕容

    ①我先是被鸟的鸣声吵醒的。

    ②是个夏日的清晨,大概有几十只小鸟在我窗外的槭树上集合了,除了麻雀的吱喳声之外,还有那种小绿鸟的嘤嘤声。我认得那种声音,年年都会有一两对小绿鸟来我的树上筑巢。在那一段时间里,我每天都能听到它们那种特别细又特别娇的鸣声,听了就让我想微笑、想再听。

    ③屋子里面还留有昨夜的阴暗和幽凉。窗帘很厚,光线不容易透进来,可是,我知道,窗户外面一定有很好的太阳,因为,从鸟的鸣声里,可以听得出它们的雀跃和欢喜。

    ④而且,孩子们也开始唱歌了,就在我的窗下。仔细分辨,唱歌的人有的是坐在矮墙上,有的是爬在树上。他们一面唱一面嘻笑,那种只有孩子们才能发出的细嫩的歌声,还有不时因为一种极单纯的快乐才能引起的咕咕格格的笑声,让睡在床上的我听了也不禁微笑起来。

    ⑤原来,早起的孩子和早起的小鸟一样,是快乐得非要唱起歌来才行的啊!

    ⑥在这些声音里,我也听出了我孩子的声音,对一个母亲来说,自己孩子的声音总是特别突出、特别悦耳的。一早起来不知道有些什么事情让他们觉得那么好笑的,那样清脆和圆润的笑声,真有点像荷叶上的露珠,风吹过来时就滑来滑去,圆滚滚的、晶亮亮的,一直不肯安静下来。

    ⑦然后,忽然间传来一声低沉的喝止:

    ⑧“小声一点,你妈妈还在睡觉。”

    ⑨那是一种低沉而宽厚的男中音,是比我起得早的丈夫出去干涉了。其实,这个时候我已经完全醒了,可是我愿意假装安静地躺在床上,享受着他给我的关怀。

    ⑩在阴暗和幽凉的室内,在我们干净而舒爽的大床上,我一个人伸展着四肢,静静地微笑着。把脸贴近他的枕头,呼吸着我最熟悉的气息,枕头套的布料细而光滑,触到我的脸颊上有一种很舒服的凉意。这是我的家,我的亲人,我热烈地爱着的生命和生活。我虽然知道在这世间没有持久不变的事物,虽然明白时光正在一分一秒地逐渐流失,可是,能够在这一刻,能够在这个夏天的早上清楚地感觉到自己的幸福,一种几乎可以听到、看到和触摸到的幸福,我恐怕是真要感谢窗外那十几棵的槭树了。

    ⑪在房子刚盖好的时候就种下的这些槭树,长得可真是快,七八年前只有手臂样粗细的幼树,现在却个个都是庞然巨物了,跟着四季的变化,把我们这栋原来非常普通的平房也带得漂亮起来。它们实在很漂亮也很尽责,春天时长出好多软软的叶子,绿得逼人,一簇簇的小花开得满树,在月亮底下每一小朵,每一小簇好像都会发亮。夏天时给我们整片的浓荫,风吹过来,说要多凉就有多凉。秋来时可以变得很黄很红,几乎所有路过的人都会忍不住摘下一两片。到冬天的时候,满树的叶子都落了,屋子里就会变得出奇的明亮,而那些小绿鸟留下的窝巢就会很醒目地在枝桠之间出现了。孩子们爬上树去拿了下来,当作宝贝一样地献给我,小小的鸟窝编织得又圆又温暖,拿在手上虽然没有一点重量,却能给人一份很扎实的快乐。

    ⑫对我来说,我的这一个槭树下的家,和它的小小窝巢也没有什么不一样啊!

    ⑬这个槭树下的家,就该是我多年来所渴望着的那一个了吧。不过是一栋普普通通的平房,不过是一个普普通通的家庭,不过种了一些常见的花草树木。春去秋来,岁月不断地重复着同样的变化,而在这些极有规律的变化之中,树越长越高,我的孩子越长越大,我才发现,原来平凡的人生里竟然有着极丰盈的美,取之不尽,用之不竭,我的心中因而常常充满了感动与感谢。

同类题5

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    When I graduated from college I dreamed of being a television news reporter. Having no experience, I had to work in a small town until I finally got my big break in the form of a job in Boston. I made it.

    Soon, reality set in. I was too often sent to run after accused criminals out of courts, waiting outside of crime scene tape or at the doorstep of a family still crying for tragedy (悲剧). My breaking point came the day I accidentally informed a young woman that her mother died. It was the worst day of my professional life and the day I decided I no longer wanted to shine a light on these stories. My career was ebbing, and at the same time my personal life was too-I divorced.

    My mom had always told me “When you're feeling extremely upset, go help someone else.” So I started seeking out stories of people who had been in the news under tragic circumstances but were doing something inspiring with their lives: a young girl who was paralyzed (瘫痪的) by an accident but was uplifting her classmates with her positive spirit, a blind and autistic (自闭的) musician who learned to play 27 instruments, a disabled soldier who opened his own art studio. I started to tell and promote stories like them.

    Over the last 10 years I have discovered my kindness gift: my ability to see the beautiful side of a person and reflect it back to them and the world. In telling stories of people turning their own hurt into acts of helping others I have become more sympathetic, more grateful and kinder. I have learned kindness is who we are, that our power for it is limitless and that, as we shine a light on it, it grows.