|
Magnetic
Resonance -
Technology
Information
Portal |
Welcome to MRI Technology • |
|
|
 | Info
Sheets |
| | | | | | | | | | | | | | | | | | | | | | | | |
 | Out-
side |
| | | | |
|
| | | | | |
| Result: Searchterm 'NMR'
found in 5 messages |
| Result Pages: [1] |
More Results:  Database (41) News Service (25) Resources (69) |
|
|
geraint davies
Thu. 27 Oct.05,
13:51
[Start of:
'NMR MOUSE'
0 Reply]
 Category:
Devices, Scanner, Machines
|
| NMR MOUSE |
the database contains knothing about the NMR MObile Universal Surface Explorer. im researching the mouse and would like to know more about its history. any info on mouse appreciated
thanks
geraint davies
|
| |  Reply to this thread
(login or register first) | |
Herbert Müller
Thu. 5 May.22,
01:33
[Reply (11 of 12) to:
'90 excitation pulse vs 180 inversion pulse'
started by: 'Bjorn Redfors'
on Sat. 27 Jun.09]
Category:
Basics and Physics
|
| 90 excitation pulse vs 180 inversion pulse |
Hello,
I dont know if anyone has, for him/herself, answered this question. I know it is an old thread. But this is the question which also botheres me the most in NMR/MRI.
I refer now to a picture, which is illustrated in the book from Tim Claridge (High resolution NMR techniques).
Here, a RF pulse (lets say a 90 degree pulse) is said to have two effects on the initial z-magnetisation. First, it allows energy transfer between the two Zeeman-states in a way, that i equalizes the population difference between them. So there is no z- magnetisation anymore after 90 degree pulse. Th esecond effect is, that it induces phase-coherence. And this phase coherence is then responsible for the x-magnetisation, which is measured.
And now I have the same question. Why is this phase coherence lost (or is it not?), when applying an initial 180-degree pulse. Understandable for me is, why the population difference in z is reversed, but I dont understand, why there is no xy magnetisation anymore.
Maybe some of you have figured out the answer in the meantime?
Greetings
|
| | View the whole thread | | | |
|
avinash poornan
Mon. 9 Feb.15,
00:45
[Start of:
'Self refocusing'
0 Reply]
Category:
Basics and Physics
|
| Self refocusing |
How do you define a self refocusing pulse in NMR?
|
| | Reply to this thread
(login or register first) | |
Glad Mihai
Mon. 26 Sep.11,
11:53
[Start of:
'Siemens CINE Sequence details'
0 Reply]
Category:
Sequences and Imaging Parameters
|
| Siemens CINE Sequence details |
Hello there fellow NMR enthusiasts, I have a question regarding the CINE-Sequence that a Siemens 3 T scanner does, in particular I am interested in the retro iPAT sequence. What I want to know is what the exact parameters are.
For example, I have set a TR of 2.7 ms, but the actual recording time of one scan is close to 300 ms. Why is that? What else gets added to this time?
If anyone has links to useful information about sequences, then I am more than happy to check them out.
Regards, Glad
|
| | Reply to this thread
(login or register first) | |
Karsten Miesel
Tue. 17 Aug.04,
02:02
[Start of:
'material with 'zero' magnetic susceptibility'
2 Replies]
Category:
Basics and Physics
|
| material with 'zero' magnetic susceptibility |
Does anybody know some material, that is still easy to machine, better non-conductive and - most important - has a susceptibility close to zero. Is there composite materials that are especially made for such purposes?
I know that coils for NMR are usually made like this, but I'm looking for some material that I could make a whole NMR probe out of. It should be non-conductive, because I don't want eddy currents.
thanks in advance, Karsten
|
| | View the whole thread | Reply to this thread
(login or register first) |
| |
| | Result Pages : [1] | |
|
| |
 | Look
Ups |
| |
|
MR-TIP.com uses cookies! By browsing MR-TIP.com, you agree to our use of cookies. | | | [last update: 2024-02-26 03:41:00] |
|
|
bottom
top
