题干

石油钻探的钻头用金刚石做,这是利用了金刚石的____ 大的物质属性,组成金刚石的碳原子是由____ 和电子组成的.

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硬度,原子核

同类题1

根据短文理解,选择正确答案。

    My writing career began ten years ago with my articles published locally and nationally. As a beginning writer, I was happy to be on my way, writing and learning as much as I could . With two little kids underfoot, as well as working full-time, it was really difficult to make time for writing, but I managed.

    Readers told me they laughed, cried or were inspired by my articles. But they didn't know what was really going on behind the typewriter. I was not a happy mommy, and found it difficult to enjoy the everyday little things in life. In short, I was not a happy person.

    I realized I had to make some changes. I started walking every morning. It cleared my head, allowed me time to think, gave me fresh air, and made me feel invigorated (精神焕发) and healthy. I was eating wisely, and the weight started to go. I started a new job, joined a monthly writing chapter,and was determined to keep up my walking. Finding the balance was sometimes difficult. But I was determined to fit in writing time because it made me happy. Sure I loved to watch the news and have my tea, but that wasn't what made me truly happy.

    My own happiness has shown through my family, my job performance and my attitude towards challenging situations. I again have readers telling me the effect my writing has had on them, with some able to get on with their own writing because of my articles.

    It was up to me to make it happen—my own happiness. One step at a time-one word at a time. And I did it.

同类题3

阅读《要快也要慢》,完成小题

要快也要慢

       ①时代发展加速,生活节奏加快,“快”成了一种时尚,一种追求。方方面面都在努力提速,以“快”为特征的行当,诸如“快餐”“快递”“快照”“快洗”“快车”等应运而兴。即使在人的感情生活中,“闪婚”“闪恋”也成了一时的风景。

       ②快是历史发展的必然。过去有句话:“一天等于二十年”。当下信息社会“一天”的发展,远远超过农业社会乃至工业社会“二十年”的发展。面对激烈的竞争,人们确实要有“只争朝夕”的精神,以适应社会的发展变化。

       ③违背事物发展规律去求快,快则快矣,得到的却是苦果子。20世纪50年代的“大跃进”,“跃”得全国人民没有饭吃,就是一个深刻的教训。时下用催生剂催长的速成水果与鸡鱼鸭肉,成长期是快了,但却变得像鸡肋一样,食之无味,弃之可惜。这样的快,带给它们的不是进化,而是退化。以牺牲环境与资源为代价的经济发展,也是得不偿失,后患无穷。我国早有“欲速则不达”和不可“拔苗助长”一类的古训,这是人类珍贵的经验之谈。

       ④就人的幸福感而言,生活也是要有快有慢,劳逸结合的。倘若人一直处在快节奏中,没有慢节奏的调剂,没有空暇,没有悠闲,没有“采菊东篱下”和“闲庭信步”的情致,那生命就会失去平衡,人生的丰富性就会大打折扣,甚至会被快节奏所击倒。“闪婚”“闪恋”快则快矣,然而,也因尝不到婚恋过程的美妙情趣,而导致了不少人“闪离”的恶果。生活中有好多东西都是需要慢慢咀嚼的。阿尔卑斯山谷有一条公路,两旁景物极美,许多驾车人视而不见,疾驶而过,管理者特意在路上插上一个劝告牌:“慢慢走,欣赏呵!”朱光潜先生在谈到人生的情趣时,特举此例,说人生艺术化,就得“慢慢走,欣赏呵!”我国有一首老歌也这样唱:“马儿呵,你慢些走、慢些走,我要把这美丽的景色看个够。”

       ⑤针对近些年来一味求快带来的负面影响,不少人又怀念起慢来,认为不要急吼吼地度过有限的人生,于是,慢文化之风开始兴起。“慢餐”“慢递”“慢游”“慢照”一类的活动渐次多了起来。北京出现了“慢递”专业店。国际上有了“慢餐协会”,他们声称,慢餐不只是细嚼慢咽,它是一种生活态度,一种心态上的慢,“以慢餐引导被物欲横流的大潮裏挟着的人们放慢脚步”。近日还传出消息,全球已经有24个国家135个城市获得“慢城”称号,我国江苏省高淳县有望于近期召开的“国际慢城会议”上被授予“慢城”称号。所谓“慢城”,主要是走“生态立城”之路,本质上可以说是一个“环保”概念。“慢”,是幸福生活所不可缺少的。

       ⑥由此可见,要辩证地看待快与慢,快有意义,慢也有价值。快节奏的霹雳舞与慢节奏的太极拳,各有各的美。要当快则快,当慢则慢,快不弃慢,慢不鄙快,让快慢正确地结合起来,在生活节奏加快的现代,使人的生活仍然保持应有的从容、放松和宁静,维护人的物质生活和精神生活的高质量。