24小时热门版块排行榜

返回列表

comehappyon

铁杆木虫 (正式写手)

应助: 1 (幼儿园)
金币: 4707
帖子: 341
在线: 265.7小时
虫号: 947216

[交流] 荧光分析

"Figure 2.30 shows the time-resolved luminescence of Eu2+-doped Sr2Si5N8 measured at varying delay times."
我在文献中看到的这段话，我做的是荧光粉，然后不明白，在荧光分析中为什么要测delay time？

回复此楼

» 猜你喜欢

» 抢金币啦！回帖就可以得到:

查看全部散金贴

1楼 2011-11-30 14:32:07

已阅关注TA 给TA发消息送TA红花 TA的回帖

padodo

至尊木虫 (职业作家)

★
小木虫(金币+0.5):给个红包，谢谢回帖
comehappyon(金币+1): delay time貌似是衰减时间，但是具体有什么理论方面的理解么？ 2011-11-30 15:03:14

应该是发光强度会随时间而变化，delay time即指放置的时间

赞一下(1人)

回复此楼

2楼2011-11-30 14:42:40

已阅关注TA 给TA发消息送TA红花 TA的回帖

chaijudi

至尊木虫 (著名写手)

ACI: 6
应助: 528 (博士)
贵宾: 0.072
金币: 10836
帖子: 1923
在线: 469.4小时
虫号: 1018198

★
小木虫(金币+0.5):给个红包，谢谢回帖
comehappyon(金币+2): 这个太抽象了，实在看不明白。 2011-12-01 08:46:13

引用回帖:

1楼: Originally posted by comehappyon at 2011-11-30 14:32:07:
"Figure 2.30 shows the time-resolved luminescence of Eu2+-doped Sr2Si5N8 measured at varying delay times."
我在文献中看到的这段话，我做的是荧光粉，然后不明白，在荧光分析中为什么 ...

Delay Lines
Delay lines, or a way to introduce time delays, are incorporated
into all TCSPC instruments. The need for delay lines
is easily understood by recognizing that there are significant
time delays in all components of the instrument. A
photoelectron pulse may take 20 ns to exit a PMT. Electrical
signals in a cable travel a foot in about 1 ns. It would be
difficult to match all these delays within a couple of
nanoseconds in the start and stop detector channels without
a way to adjust the delays. The need for matching delays
through the components is avoided by the use of calibrated
delay lines. Such delays are part of the NIM bin electronics.
However, lengths of coaxial cable are prone to picking up
RF interference.
Calibrated delay lines are also useful for calibration of
the time axis of the MCA. This is accomplished by providing
the same input signal to the start and stop channels of
the TAC. The preferred approach is to split an electrical signal,
typically from the start detector, and direct this signal
to both inputs of the TAC. Since the pulses arrive with a
constant time difference, one observes a single peak in the
MCA. One then switches the time delay in the start or stop
channel by a known amount, and finds the peak shift on the
MCA display. By repeating this process for several delay
times, the TAC and MCA can be calibrated.

自己多看几次，估计能看明白

赞一下(1人)

回复此楼

3楼2011-11-30 15:47:43

已阅关注TA 给TA发消息送TA红花 TA的回帖