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ice625

铜虫 (正式写手)

[求助] 3道光谱基础知识的选择题

新人向大神求救,望大神帮忙指点一下,每一个题稍微解释一下
1.Integration is a noise-reduction technique that works if the major noise sources are …
a. 1/f in nature.
b. white in nature.
c. only fundamental in nature.
d. impulse noise.

2.What is the difference between the cells used in UV-visible fluorescence compared to those used in UV-visible absorption spectroscopy?
a. Fluorescence cells must be made of silica, while absorption cells can be made from various materials, depending on the wavelength of absorption.
b. Fluorescence cells can be made from various materials, depending on the wavelength of absorption, while absorption cells must be made of silica.
c. Absorption cells are normally frosted on two sides and clear on the other two sides, while fluorescence cells are clear on all four sides.
d. Fluorescence cells are normally frosted on two sides and clear on the other two sides, while absorption cells are clear on all four sides.
e. a. and c.
f. b. and d.
g. a. and d.
h. b. and c.

3.Pre-filtering…
a. is absorbance of excitation photons prior to the observation volume.
b. is absorbance of excitation photons in the observation volume.
c. is absorbance of emission photons in the observation volume.
d. is absorbance of emission photons after the observation volume but prior to the detector.
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leefadisky

木虫 (小有名气)

【答案】应助回帖

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感谢参与,应助指数 +1
ice625: 金币+10, ★★★★★最佳答案 2013-09-19 01:08:43
suruiqin: 金币+1, 辛苦了,鼓励交流,欢迎常来分析版~ 2013-09-19 09:38:57
1、b  积分可降低功率谱密度在整个频域内均匀分布的白噪声
2、e   荧光与吸收的不同在于,荧光是发光而吸收是对入射光的吸收;所以荧光样品池必须是四面光滑的玻璃材料,吸收之需要是光线通过的两面是透光的,另两面是粗糙的且材质可根据样品的吸收峰选择
3、发射光谱在激励波长的2倍位置会有强烈的强度,我觉得这个预滤波就是消除它对反射谱的影响,这样可能就是d。

这些题目都挺好的,直接关联仪器的本质。相应的题目或讲义,方便的话,请给我一份,谢谢
2楼2013-09-18 19:59:21
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ice625

铜虫 (正式写手)

引用回帖:
2楼: Originally posted by leefadisky at 2013-09-18 19:59:21
1、b  积分可降低功率谱密度在整个频域内均匀分布的白噪声
2、e   荧光与吸收的不同在于,荧光是发光而吸收是对入射光的吸收;所以荧光样品池必须是四面光滑的玻璃材料,吸收之需要是光线通过的两面是透光的,另两 ...

真的对我有帮助,多谢,下次有分析问题还请多多指教
没有一颗心会因为追求自己的梦想而受伤!
3楼2013-09-19 01:09:14
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