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核磁问题求教

核磁问题求教# Chemistry - 化学

n*s2010-06-21 07:06

1 楼

Does anyone know if H1B go back to China for 2-3 weeks vacation, but H4 stay
at USA is it OK?

z*q2010-06-21 07:06

2 楼

最近要做一个TOCSY类(HCCNH-TOCSY)的实验，需要计算TOCSY spinlock and pulse
power.查了相关文献，但是文献中给的spinlock都是以赫兹为单位的，还有给rf field
(Hz or ppm）的，想请教NMR达人，怎么将文献中的数值换成实验上可用的parameter
？我们用的是bruker 600MHz cryoprobe.有人曾做过类似实验么？可否教我怎么设定这
类实验？我是nmr新人，太多东西要学了，有点不知所措，还望达人们不吝赐教！万分
感谢！

h*32010-06-21 07:06

3 楼

It should be OK. I hold H4 and stayed at USA while H1 left USA for one week.
No trouble.

t*t2010-06-21 07:06

4 楼

this is hard to explain in a few words.
you need the shape tool of bruker to calculate them
you should ask your NMR lab manager for help

n*s2010-06-21 07:06

5 楼

Thanks.

z*q2010-06-21 07:06

6 楼

Thank you for your reply!
I have asked them already. None of the seniors or the NMR manager knows that
. Even the boss said there had been too many years since she could set up
the experiments by herself. She almost forgot everything. She can only help
with assignment. That is why I think I need to figure this out by myself.
Thank you anyway!

【在 t******t 的大作中提到】

: this is hard to explain in a few words.
: you need the shape tool of bruker to calculate them
: you should ask your NMR lab manager for help

t*r2010-06-21 07:06

7 楼

这都不行还让不让人活了.

stay

【在 n**s 的大作中提到】

: Does anyone know if H1B go back to China for 2-3 weeks vacation, but H4 stay
: at USA is it OK?

o*a2010-06-21 07:06

8 楼

first you can get the 90 deg pulse width at your desired spin lock level.
(spink lock level in hz, the nutation freq)
pw90sl = 1/(4*tpwr_sl) Note 90 deg takes 1/4 of a full circle.
Then use the following equation to get spin lock power in dB
tpwr - 20.0*log10(pw90sl/pw90)
tpwr_sl: spin lock power in hz
tpwr: regular hard pulse power in dB
pw90: regular 90 deg pulse width
Make sure you understand what you are doing. Be very careful with spin lock.
It's one of the few things that can smoke the pro

【在 z***q 的大作中提到】

: Thank you for your reply!
: I have asked them already. None of the seniors or the NMR manager knows that
: . Even the boss said there had been too many years since she could set up
: the experiments by herself. She almost forgot everything. She can only help
: with assignment. That is why I think I need to figure this out by myself.
: Thank you anyway!

L*h2010-06-21 07:06

9 楼

of course it is ok.
If you don't came back again, there's a big problem.

stay

【在 n**s 的大作中提到】

: Does anyone know if H1B go back to China for 2-3 weeks vacation, but H4 stay
: at USA is it OK?

z*q2010-06-21 07:06

10 楼

This would make sense! I think I've got it.Thank you very much for your help
! I will monitor the cryopanel to prevent any damage! Thanks again!

lock.

【在 o**a 的大作中提到】

: first you can get the 90 deg pulse width at your desired spin lock level.
: (spink lock level in hz, the nutation freq)
: pw90sl = 1/(4*tpwr_sl) Note 90 deg takes 1/4 of a full circle.
: Then use the following equation to get spin lock power in dB
: tpwr - 20.0*log10(pw90sl/pw90)
: tpwr_sl: spin lock power in hz
: tpwr: regular hard pulse power in dB
: pw90: regular 90 deg pulse width
: Make sure you understand what you are doing. Be very careful with spin lock.
: It's one of the few things that can smoke the pro