题目

下列关于自然界中氮循环(如右图)的说法不正确的是A. 人工固氮可以得到硝酸盐B. 细菌对氮元素的循环有重要作用C. 雷电作用可以将氮气直接转化为铵盐D. 亚硝酸盐转化为硝酸盐的过程中,氮元素被氧化 答案:【答案】C【解析】A. 工业上以氮气合成氨,然后通过氨的催化氧化法制硝酸,再以硝酸制硝酸盐,所以人工固氮可以得到硝酸盐,A正确;B. 由图可知,豆科植物的根瘤菌可以固氮,所以细菌对氮元素的循环有重要作用,B正确;C. 雷电作用只能将氮气转化为一氧化氮,不可以将氮气直接转化为铵盐,C不The moment happened 20 years ago but it was still fresh in my memory. I was a college freshman and had 36 up most of the night before laughing and talking with friends. Now just before my first 37 of the day my eyelids were feeling heavier and heavier and my head was drifting down to my desk to make my textbook a 38 . A few minutes’ nap(小睡)time before class couldn’t 39 , I thought.BOOM! I lifted my head suddenly and my eyes opened wider than saucers. I looked around with my 40 beating wildly trying to find the cause of the 41 . My young professor was looking at me with a boyish smile on his face. He had 42 dropped the textbooks he was carrying onto his desk. “Good morning!”, he said still 43 . “I am glad to see everyone is 44 . Now let’s get started. ”For the next hour I wasn’t sleepy at all. It wasn’t from the 45 of my professor’s textbook alarm clock either. It was instead from the 46 discussion he led. With knowledge and good  47 he made the material come 48 . His insight was full of both wisdom and loving-kindness. And the enthusiasm and joy that he 49 with were contagious(有感染力的). I 50 the classroom not only wide awake, but a little 51 and a little better as well. I learned something far more important than not 52 in class that day too. I learned that if you are going to do something in this life,do it well,do it with 53 . What a wonderful place this would be if all of us did our work joyously and well. Don’t sleepwalk your way through 54 then. Wake up! Let your love fill your work. Life is too 55 not to live it well. 36.A. took             B. stayed           C. spent           D. put37.A. task           B. test             C. class            D. lecture38.A. pillow          B. shadow          C. basis            D. comfort39.A. inspect         B. disturb              C. hurt       D. bend40.A. head            B. mind            C. thought          D. heart41.A. noise           B. trouble              C. voice            D. incident42.A. angrily           B. deliberately        C. carelessly         D. accidentally43.A. shouting        B. sighing           C. complaining       D. smiling    44.A. active            B. curious      C. awake      D. present    45.A. shock           B. sound          C. interruption        D. blow46.A. convincing        B. fascinating       C. puzzling          D. encouraging47.A. gesture           B. sense            C. design      D. humor 48.A. strange           B. natural           C. alive             D. handy49.A. spread           B. taught          C. combined         D. started50.A. left            B. seated           C. decorated         D. entered51.A. clearer             B. quieter           C. smarter          D. stronger52.A. discussing        B. speaking          C. sleeping          D. cheating53.A. determination      B. religion         C. strength          D. joy 54.A. life              B. work           C. journey          D. college55.A. hard             B. short         C. complex          D. simple
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