为什么血管看起来是蓝色的？

时间：2009-02-02 05:17:15

（单词翻译:单击）

不知您注意过没有，我们胳膊上、腿上的血管看起来都不是红色的，而是呈现出近似于青色、蓝色的颜色。这又是什么原因呢？原来，都是波长惹的祸。

Surprisingly, the reason why the blood in our veins2 looks blue only emerged in 1996 following research done by the physicist3 Dr. Lothor Lilge and his colleagues at the Ontario Laser and Light Wave Research Centre of Canada. They showed that when light strikes white skin, the longer, redder wavelengths4 penetrate5 deeper, and are absorbed by the blood vessels7. As a result the light reflected back from the skin covering a blood vessel6 has a relatively8 higher proportion of the shorter wave lengths which gives it is blue-purple tinge9. The veins of people with dark skin don't show this effect so strongly because the skin's melanin absorbs almost all wavelengths of light on the skin's surface.

The reason we go red rather than blue when we blush is because of the relative depths of the blood vessels affected10. According to Dr Lilge, a vein1 has to be at least 0.5 mm below the skin's surface to look blue .The small capillaries11 that fill up with blood when we blush are much closer to the skin's surface and so look red.

capillary: 毛细管


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1 vein fi9w0     
n.血管，静脉；叶脉，纹理；情绪；vt.使成脉络
参考例句：
  • The girl is not in the vein for singing today.那女孩今天没有心情唱歌。
  • The doctor injects glucose into the patient's vein.医生把葡萄糖注射入病人的静脉。
2 veins 65827206226d9e2d78ea2bfe697c6329     
n.纹理；矿脉( vein的名词复数 )；静脉；叶脉；纹理
参考例句：
  • The blood flows from the capillaries back into the veins. 血从毛细血管流回静脉。 来自《简明英汉词典》
  • I felt a pleasant glow in all my veins from the wine. 喝过酒后我浑身的血都热烘烘的，感到很舒服。 来自《简明英汉词典》
3 physicist oNqx4     
n.物理学家，研究物理学的人
参考例句：
  • He is a physicist of the first rank.他是一流的物理学家。
  • The successful physicist never puts on airs.这位卓有成就的物理学家从不摆架子。
4 wavelengths 55c7c1db2849f4af018e7824d42c3ff2     
n.波长( wavelength的名词复数 )；具有相同的/不同的思路；合拍；不合拍
参考例句：
  • I find him difficult to talk to—we're on completely different wavelengths. 我没法和他谈话，因为我们俩完全不对路。 来自《简明英汉词典》
  • Sunlight consists of different wavelengths of radiation. 阳光由几种不同波长的射线组成。 来自辞典例句
5 penetrate juSyv     
v.透(渗)入；刺入，刺穿；洞察，了解
参考例句：
  • Western ideas penetrate slowly through the East.西方观念逐渐传入东方。
  • The sunshine could not penetrate where the trees were thickest.阳光不能透入树木最浓密的地方。
6 vessel 4L1zi     
n.船舶；容器，器皿；管，导管，血管
参考例句：
  • The vessel is fully loaded with cargo for Shanghai.这艘船满载货物驶往上海。
  • You should put the water into a vessel.你应该把水装入容器中。
7 vessels fc9307c2593b522954eadb3ee6c57480     
n.血管( vessel的名词复数 )；船；容器；（具有特殊品质或接受特殊品质的）人
参考例句：
  • The river is navigable by vessels of up to 90 tons. 90 吨以下的船只可以从这条河通过。 来自《简明英汉词典》
  • All modern vessels of any size are fitted with radar installations. 所有现代化船只都有雷达装置。 来自《现代汉英综合大词典》
8 relatively bkqzS3     
adv.比较...地，相对地
参考例句：
  • The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
  • The operation was relatively painless.手术相对来说不痛。
9 tinge 8q9yO     
vt.(较淡)着色于，染色；使带有…气息；n.淡淡色彩，些微的气息
参考例句：
  • The maple leaves are tinge with autumn red.枫叶染上了秋天的红色。
  • There was a tinge of sadness in her voice.她声音中流露出一丝忧伤。
10 affected TzUzg0     
adj.不自然的，假装的
参考例句：
  • She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
  • His manners are affected.他的态度不自然。
11 capillaries d0d7ccc2f58ea09ec26e13a0d6ffd34a     
毛细管，毛细血管( capillary的名词复数 )
参考例句：
  • The blood flows from the capillaries back into the veins. 血从毛细血管流回静脉。
  • While Joe sleeps, a large percentage of his capillaries are inactive. 当乔睡觉时，他的毛细血管大部分是不工作的。

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