本文节选自《经济学人》的一篇文章，介绍了关于指纹技术在犯罪中的运用局限性以及新研究的改进
本文共节选7段，建议大家先自主阅读原文，再学习精读笔记。
文末会总结此次学习写作可以使用的词句，读者也可自己总结。会定期将内容进行总结，做成word分享，希望大家也能坚持学习
1
Since the first use of fingerprints to identify and convict a murderer, in 1892, detectives the world over have come to rely heavily on print evidence to build their cases against suspects. One limit on the value of fingerprints, though, is that it is hard to work out how old they are. This is a particular problem when a crime is committed somewhere that a suspect frequently and legitimately visits, such as a place of work. In this case exactly when a print was made might be crucial to establishing guilt or innocence. But it is information that science has, until now, been unable to provide with any accuracy.
Since the first use of：自第一次使用……以来【词组积累】
identify and convict a murderer：确认并定罪，identify表示确认，找到罪犯，而convict则表示定罪，宣判……有罪【词汇积累】
the world over：全世界（例如cultures
the world over feted the winter solstice as the moment of the sun's return世界各地的文化都广泛庆祝冬至日，因为它是太阳回归的日子）。这个词组经常紧接在主语之后。【词组积累】have come to：渐渐……
rely heavily on：heavily是heavy的副词形式，修饰rely，表示依赖程度重【搭配】
print evidence：指纹证据
One limit on：……的一个限制是【词组积累】
legitimately：正当地，合理地【词汇积累】
be crucial to establishing guilt or innocence：be crucial to doing表示某事至关重要，establish guilt or innocence确定有罪或无罪，establish有查实；确定；证实to discover or prove the facts of a situation。同义的词可以用prove代替，如prove guilty or innocent【搭配】
provide with any accuracy.：provide with accuracy提供精确的证据【词组积累】
自1892年指纹第一次被用来寻找并给病人定罪以来，全世界的侦探对利用指纹来解决案件的依赖越来越重。然而，指纹的一个限制是它无法告诉我们它存在了多久。这是一个特殊的问题，尤其是当一个嫌犯反复、合法地进入犯罪场所时，例如工作场所。这种情况下，当一个指纹被确定时，或许对确认犯人有罪或无罪至关重要。
2
As they write in Analytical Chemistry, Paige Hinners and Young Jin Lee of Iowa State University believe they can remedy this state of affairs. They knew from work conducted by other laboratories that the triglyceride oils contained in fingerprints change by oxidation over the course of time. That provides an obvious way to date prints. The problem is that the techniques which have been applied to analyze these oils are able to distinguish age only crudely. In practice, they can determine whether or not a print is over a week old, but nothing else.
remedy this state of affairs：改进这个情况。remedy作名词有改进措施的意思，作动词表示补救、改进；state of affairs表示事态，状况【搭配】
work conducted by other laboratories：conducted by表示经由……执行、实行，work在这里表示研究工作【搭配】
triglyceride oils：甘油三酯
over the course of time：随着时间……【词组积累】
distinguish age only crudely：只能粗略地区分年龄，crudely表示粗糙地，模糊地，所以distinguish sth crudely表示粗略地分别【搭配】
determine whether or not a print is over a week old,：determine表示下定决心去做，这里的意思是查明；测定；准确算出to discover the facts about sth; to calculate sth exactly，即测定指纹是否超过一周【熟词僻义】
正如艾奥瓦州立大学的Paige Hinners和Young Jin Lee他们在分析化学中写道，他们相信他们可以改进这个情况。他们从其他实验室的工作中了解到，指纹中的甘油三酯会因为氧化作用随着时间而改变。这提供了一个追溯指纹很显然的方式。问题是，用来追踪这些物质的技术只能很粗糙地分辨这些指纹的年龄。事实上，他们仅仅可以确定一个指纹是否超过一周，而不能做其他事情。
3
Dr Hinners and Dr Lee wondered if higher precision could be obtained by thinking a bit more about oxidation. Oxygen molecules in the air come in two varieties. Most have a pair of atoms but some, known as ozone, have three. Though far rarer than diatomic oxygen, ozone is more reactive and also reacts in ways different from those of its two-atomed cousin. The two researchers therefore decided to focus their attentions on ozonolysis.
Sb wonders if higher precision could be obtained by thinking a bit more about oxidation：某人想知道是否可以通过多思考氧化的问题使预测可以更精确，这里的句式是sb wonders if …… could be obtained by doing sth。某人想知道是否可以通过做某事来达成某个目的【句式】
Sth comes in two varieties：某些事物有两种【词组积累】
diatomic oxygen：双原子氧气
两位博士想知道是否可以通过多思考氧化的问题使预测可以更精确。空气中的氧分子有两种形式，大多数是两个原子，而有一些，如臭氧有3个原子。尽管远罕见于双原子氧，臭氧反应更强，而且反应的方式与那些2原子表亲不同。因此，两个研究人员决定花更多的时间在臭氧分解上。
4
Triglycerides, as their name suggests, are three-tailed molecules. Each tail is a chain of carbon atoms, with hydrogen atoms bonded to the carbons. The chains are held together by bonds between the carbon atoms. These are of two varieties, known as single and double bonds. Single bonds are, in chemistry-speak, saturated, and double bonds unsaturated. By extension, molecules with one or more double bonds in them are also referred to asunsaturated, while those with only single bonds are called saturated.
bond to：bond中文释义里有化学键的意思，所以这里bond to表示某原子与其他原子相连【熟词僻义】
known as：known for表示以……闻名，known as更多的意思是被称为，被认为是，known as single and double bonds，被称为单链或双链【词组积累】
in chemistry-speak：用化学的话来说
by extension：扩展而言，由此可推论【词组积累】
are referred to as unsaturated; are called saturated：两个都可以翻译为被称作【同意替换】
正如其名字所写，甘油三酯是三支链分子，每个支链都是碳原子链，每个碳原子是都有氢原子与其相连。碳链是由碳原子间的化学键连接在一起的。这种链包含两种，被称为单链或双链，单链从化学术语来说，是饱和链，而双链则是不饱和链。由此可推论，拥有一个或多个双链的分子也被称为不饱和的，而那些仅仅只有单链的则是饱和分子。
5
Unsaturated bonds are more reactive, and it is here that ozonolysis does its work. Ozone breaks up triglycerides at their double bonds, with one or more of the ozone’s oxygen atoms becoming attached to the carbon chain, to create new chemical species. In principle, this should result in a gradual loss of unsaturated triglycerides and aconcomitant rise in the reaction products of ozonolysis.
become attached to：依附在……上
In principle：原则上来说
result in：导致
a gradual loss of sth：某物的缓慢丢失；对应反义词a concomitant rise in：伴随着……的上升，concomitant表示同时发生的【词汇积累】
不饱和链更容易反应，而这正是臭氧分解发挥作用的地方。臭氧破坏甘油三酯的双链，并将自己的氧原子依附在碳链上，从而制造新的化学物质。原则上来说，这会导致不饱和甘油三酯的丢失，随之而来的是臭氧分解带来的产物的上升。
6
And that, in practice, is what Dr Hinners and Dr Lee found. They asked three volunteers to leave their prints ona number of glass slides. They then tested some of those slides immediately, using a sensitive analytical technique called matrix-assisted laser desorption/ionisation (maldi) to produce a spectrum of the prints’ chemical contents. The other slides they left exposed to the air for between one and seven days, testing them at regular intervals
in practice：事实上
a number of glass slides：大量的，下文中的a spectrum of the prints’ chemical contents：a spectrum of 表示一系列的
glass slides：载玻片【词汇积累】
at regular intervals：每隔一定的时间。【词组积累】
事实上，这正是Hinners和Lee 所发现的。他们让3位自愿者在大量的载玻片上留下自己的指纹，随后，他们立即使用一种灵敏的分析技术，称作matrix-assisted laser desorption/ionisation (maldi)，来检测这些载玻片，并产生一系列指纹的化学物质。而其他载玻片，他们则暴露在空气中1到7天，并每隔一定时间进行检测。
7
As they suspected, as time progressed the ratio of saturated to unsaturated triglycerides in a sample rose, and so did the quantities of two characteristic products of ozonolysis. On the basis of what is, admittedly, a small sample, Dr Hinners and Dr Lee therefore think that maldi analysis of fingerprint residues should prove accurate enough to date to within 24 hours when a fingerprint under a week old was made.
as time progressed：随着时间的推进【词组积累】
fingerprint residues：指纹残留物，residue表示残渣，残余物
正如他们所怀疑的，样本中的饱和甘油三酯与不饱和的比值随着时间流逝而提升，而臭氧分解的两种典型产物也是如此。在这个小样本的基础上，Hinners和Lee认为指纹残留物的maldi分析可以把1周内留下的指纹时间足够精确到24h内。
总结
identify and convict a murderer：确认并定罪，identify表示确认，找到罪犯，而convict则表示定罪，宣判……有罪【词汇积累】
legitimately：正当地，合理地【词汇积累】
a gradual loss of sth：某物的缓慢丢失；对应反义词a concomitant rise in：伴随着……的上升，concomitant表示同时发生的【词汇积累】
glass slides：载玻片【词汇积累】
Since the first use of：自第一次使用……以来【词组积累】
the world over：全世界（例如cultures the world over feted the winter solstice as the moment of the sun's return世界各地的文化都广泛庆祝冬至日，因为它是太阳回归的日子）。这个词组经常紧接在主语之后。【词组积累】
One limit on：……的一个限制是【词组积累】
provide with any accuracy.：provide with accuracy提供精确的证据【词组积累】
over the course of time：随着时间……【词组积累】
Sth comes in two varieties：某些事物有两种【词组积累】
known as：known for表示以……闻名，known as更多的意思是被称为，被认为是，known as single and double bonds，被称为单链或双链【词组积累】
by extension：扩展而言，由此可推论【词组积累】
at regular intervals：每隔一定的时间。【词组积累】
as time progressed：随着时间的推进【词组积累】
rely heavily on：heavily是heavy的副词形式，修饰rely，表示依赖程度重【搭配】
be crucial to establishing guilt or innocence：be crucial to doing表示某事至关重要，establish guilt or innocence确定有罪或无罪，establish有查实；确定；证实to discover or prove the facts of a situation。同义的词可以用prove代替，如prove guilty or innocent
【搭配】remedy this state of affairs：改进这个情况。remedy作名词有改进措施的意思，作动词表示补救、改进；state of affairs表示事态，状况【搭配】
work conducted by other laboratories：conducted by表示经由……执行、实行，work在这里表示研究工作【搭配】
distinguish age only crudely：只能粗略地区分年龄，crudely表示粗糙地，模糊地，所以distinguish sth crudely表示粗略地分别【搭配】
determine whether or not a print is over a week old,：determine表示下定决心去做，这里的意思是查明；测定；准确算出to discover the facts about sth; to calculate sth exactly，即测定指纹是否超过一周【熟词僻义】
bond to：bond中文释义里有化学键的意思，所以这里bond to表示某原子与其他原子相连【熟词僻义】
are referred to as unsaturated; are called saturated：两个都可以翻译为被称作【同意替换】
Sb wonders if higher precision could be obtained by thinking a bit more about oxidation：某人想知道是否可以通过多思考氧化的问题使预测可以更精确，这里的句式是sb wonders if …… could be obtained by doing sth。某人想知道是否可以通过做某事来达成某个目的【句式】
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