[揽瓜阁精读]70.蓝宝石

喵呜包子酱

蓝宝石展现的PH是一种可以区分天然蓝宝石和合成宝石的方法；
PH的定义是glow in the dark，由含有氮气的杂质的钻石从蓝到粉再到红；
科学家做实验：天然钻石发出两种波长的可见光500&660，每块石头峰值和衰弱周期不同
合成或灰石无660，PH可以区分天然宝石和人工蓝宝石
大宝石不同部分的PH差异可忽略

Rachellily

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筱雅Jane510

70 Aug 14  19'56''

[Main Idea] Ph can be used to identify gemstones and to distinguish nature blue diamonds from synthetic ones by studying their various light colors and wavelengths.

[Structure]
P1:Main Idea
P2:Why use Ph(common process, color range)
P3:The study(objects, types, method)
        P4:Study result 1(identify stones)
        P5:Study result 2(distinguish nature blue diamonds)
        P6:Study result 3(identify pieces of a large diamond)

[Each Paragraph]
P1: Ph can be used to identify gemstones and to distinguish nature blue diamonds from synthetic ones.
P2: Ph is a common process in IIb diamond. The stone absorb energy and then release slowly in the form of light. The colors  ranging from blue throught pink to red. The orange-red light is visible for 1 minute.
P3: Lots of visitors have seen the H Diamond,but with little scientific attention.Then E-M and her colleague studied HD,AHC,BHD, and ABC, altogether 67 natural ones, 3 synthetice ones, and a gray one.They measure the wavelengths.
P4: E-M found that Ph is not rare, and all IIb diamonds glow at 2 wavelengths: 500-nm with greenish-blue light; 660-nm with red light. Peak intensities and rates of the emissions can identify the diamonds.
P5: Synthetic and gray ones don't glow at 660-nm wavelength.That can distinguish nature blue ones from the others.
P6: Ph from a piece of the large stone is same to the large one, so Ph can identify even when the stone has been cut to smaller pieces.

miiga

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儂子

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Rachellily

【文章结构】怎么辨别蓝宝石
1. 引出主题--介绍一种cheap, easy辨别宝石的方法——P，可以区分人造和自然的宝石
2. 具体介绍这个方法P：之前被物质吸收的energy释放，expose to 光，看color
3. 描述过程：一个research团队借了一大堆宝石回去研究
4. 继续介绍方法：看一种红光，所有自然宝石可以放出其中一种光
5. 说明这个方法的好处：可以解决现在market的主要问题
6. 说明方法的应用范围：还可以identify pieces

Asda7

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miiga

用时：4min12s

P1 介绍磷光现象能识别宝石，区分宝石真假

Eerie phosphorescence

• easy cheap way to identify gemstone
• distinguish natural diamonds from synthetic ones
  
  

P2磷光现象怎么产生

Phosphorescence

• Energy released in the form of light
• Common in IIB diamonds
  
  

P3 测试磷光现象

Studied 67 natural blue diamonds, 3 synthetic ones, and a gray diamond

• Shine a high-intensity ultraviolet light 20 seconds
• Measured its phosphorescence at various wave lengths
  
  

P4测试结果

EM：reddish phosphorescence is rare

Tests: 2 visible wave lengths(common)

• 500 nanometer greenish-blue
• 660 nanometer reddish
• Dictate the hue of overall glow
• Peak intensities of emission and the wane rates= virtual fingerprint
  
  

P5磷光现象如何帮助区分真假

Solve one of the big problems in the diamond market

	500 nanometer greenish-blue	660 nanometer reddish
natural blue diamonds	√	√
Synthetic diamond	√	×
gray diamond	√	×

P6磷光现象如何帮助辨别宝石

Variation in phosphorescence are negligible for any part of a stone

• Identify if it were stolen or cut
  
  

itsyuqi

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pongdo

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