当我还是铀-238时，你对我的体重一直挑剔。我期待和祈祷了五十亿年，终于进行了一次α衰变。两个质子、两个中子离开了我的身体，我变成了钍-234。
在麻省理工学院的公开课《化学原理》上，Catherine Drennan教授分享了一首化学诗Days of Our Half Lives（《我们半衰期的日子》）。视频可见于http://open.163.com/newview/movie/free?pid=M6TUCF6FT&mid=M6TUL3NFT，从12分40秒至17分50秒。原视频的中文翻译基本正确，不过有些地方没有理解英文的俏皮话，本文作者在下面给出了翻译和注释。
这首诗的作者是马萨诸塞州韦尔斯利学院（Wellesley College）教授Mala Radhakrishnan，她曾经在麻省理工学院获得化学博士学位。这首诗用一个感情故事的形式，讲述了铀-238衰变成一系列核素的过程。作者下了很大的功夫，使全诗不但韵律工整，而且在化学知识上也是正确的。该诗选自Mala的化学诗集Chemistry for the Couch Potato。Couch是长沙发，美国人把那些吃饱饭后整天窝在沙发里看电视的人称为couch potato（沙发土豆），非常形象地对应中文的“葛优躺”。阅读“懒人的化学”，是个不错的了解化学知识的方法。My dearest love, I'm writing you to tell you all that I've been through.I've changed my whole identity,But loved, I cannot pretend to be.You were on my case to start losing weight.你对我的体重一直挑剔。【注释：on sb's case : 不停地指责】
For five billion years I hoped and I prayed,And finally I had an alpha decay.Two protons, two neutrons went right out the door,And now I was thorium 234.But my nucleus was still unfit for your eyes,Not positive enough for its large size.But this time my half-life was really not very long,Because my will to change was quite strong.It took just a month, not even a millennium,To beta decay into protactinium.But you still rejected me right off the bat,但你马上拒绝了我：【注释：right off the bat : （美国俚语）立刻，马上】
Protactinium—who's heard of that?So, beta decay, I did much more to become uranium 234.Myself again, but a new isotope,You still weren't satisfied, but I still had hope.Three alpha decays, it was hard, but I stayed onThrough thorium, through radium, and then radon.I thought I would finally please you,My mass was a healthy 222.But you said, although I like your mass,I do not want to be with a noble gas.You had a point, I wasn't reactive,So in order to please you, I stayed proactive.A few days later I found you and said,Two more alpha decays and now I am lead.You were not too keen on my mass number of 214.I had a bad experience with that mass before,An unstable astatine walked right out the door.So in order to change, I went away,But all I could do was just beta decay.My hopes and my dreams started to go under,Because beta decay doesn't change a mass number.To bismuth, then polonium, I hoped and I beckoned,My half-life was 164 microseconds.And then finally I alpha decayed,And then I was lead with the prize worthy mass of 210.I've got to admit I was getting quite tired,My patience with you had nearly expired.You were more demanding than any I dated,And much of my energy had already been liberated.But you still weren't happy, but you had a fix,I really like the number of 206.So I waited for years until the day,Which began with another beta decay.And then one more, and finally in the endI alpha-ed to lead 206, my friend.To change any further I wouldn't be able,No longer active, but happily stable.It took me billions of years to do,And look how I changed and all just for you.And wait, what did you say?that I'd rather be with a young lass of gold”We're through, my pumpkin.我们结束了，亲爱的。【注释：pumpkin : （口语）亲爱的】
Shouldn't all my effort be counting for something?Well, you won't be able to rule me anymore,Because I'm leaving you, not for one atom, but four.That's right. When you were away defusing,I met some chlorines that I found quite amusing.So we're going to form PbCl4,And you won't be hearing from me anymore.See, over the years I've grown quite wise,I've learned that love is about compromise.You still have half of your half-lives to live,So now you go out there, it's your turn to give.背景简介：本文作者徐泓，同济大学城市规划系本科，中国石油大学（北京）化学工程与技术专业博士研究生。中国科普作家协会会员。作者授权风云之声首发。
