What is Magnetic resonance: Definition and 24 Discussions
Magnetic resonance is a process by which a physical excitation (resonance) is set up via magnetism.
This process was used to develop magnetic resonance imaging and Nuclear magnetic resonance spectroscopy technology.
It is also being used to develop Nuclear magnetic resonance quantum computers.
Hello,
I have a question regarding the limitations of Electron Spin Resonance (ESR). I've read somewhere that ESR cannot detect radicals with short lifetimes.
I'm trying to understand why is that?
For example: a highly dynamic system like liquid sulfur at high temperatures, where sulfur...
I have found articles that show T1 and T2 values for mineral oil and I compare them to mine and there is over 50% error also I know that T1>T2 but mine numbers don't follow that scheme.
"B0 is a static magnetic field (produced by a superconducting magnet) that initially causes the protons in the body to align with the field and precess at the larmor frequency along the z axis .
From a mathematical perspective this precession around the B0 axis occurs due to the time evolution...
Hi, can anyone provide literature that explains nuclear magnetic resonance spectroscopy in terms of a quantum mechanical theory?
Could QED explain NMR in its entire phenomenon?
In nuclear magnetic resonance, when should one process spectra in absorption mode and when - in magnitude mode? What is benefit of using the first one and the second one? For example, I need to integrate spectrum. In this case, what should I use - absorption or magnitude mode?
Homework Statement
J-coupling term between two spins is
HJ = ħJ/4 σz(1) σz(2)
In the measured magnetization spectrum of the spins, this leads to the splitting of the individual
spin lines by frequency J, which we’ll now derive. We can write the magnetization of spin 1 as:
<M1(t)> =...
I'm reading about the theory behind MRI, specifically from Farr's Physics for Medical Imaging, 2nd Edition, by Allisy-Roberts and Williams.
According to this book, the spins of the free protons in a sample line up, either parallel or antiparallel, with the externally applied magnetic field. In...
Please explain Nuclear Magnetic resonance and how it is applied to other fields? I know it has to do with magnetic field around atoms and stuff like spectroscopy and imaging. But please correct me and please go in dept with Nuclear magnetic resonance.
Hi pf,
Please could someone kindly answer a few questions about proton spin in the context of MRI. As I understand it when an external static magnetic field is applied to a patient the magnetic dipole moments of the protons in the hydrogen nuclei will experience a torque causing them to align...
Hi everyone. I'm just looking for an online description of the nuclear magnetic resonance machine, with explanations of all components, and their physical principles...anyone can help me? Giving me any link to a website talking about it?
In addiction, could be this be a valid topic for a...
My physics buddy and I have been having a debate. I was claiming that even under the natural Earth's magnetic field that with good signal to noise ratio based on the radar systems scaled appropriately the top layers of the Earth could be seen. He claimed that the signal to noise ratio of the T1...
The energy difference between two nuclear spin states in an external magnetic field B is given by
\Delta E = \gamma \hbar B
Why does resonant absorption of electromagnetic radiation by nuclear spins take place at the Larmor frequency? Shouldn't it be that the photon energy is equal to the...
I want to understand MRI and what exactly is T2. I have read the November issue of Sci-am and I'm still confused what exactly is T2 as it has different descriptions. The article "The Incredible Shrinking Scanner" by Bernhard Blumich:
"The system can also monitor the precessing spins as they...
... I recently graduated with a BA in physics with less than three months experience in physics research with a not so fantastic GPA. I don't want to go back to school and further my education because I don't want to continue to borrow money for loans to pay for college tuition . What kinds of...
I am trying to understand the theory behind nuclear magnetic resonance. I have been reading various explanations (some more detailed than others) but I still have several holes in my understanding and I hope that some of you can help clear them up.
I realize there are quite a lot of...
Hi all:
One system consists of two neutrons. both spin magnetic moments are 1/2. At a instant time, neutron 1 locates position 1 and neutron 2 is in position. As we know, spin magnetic moment is kind of dipole moment. They can generate magnetic field (not electric field). The interaction can be...
Hi all:
I have one confused concept about T1 relaxation time in nuclear magnetic resonance field.
As we know, fluctuation of local magnetic field inside the sample causes T1 decay in the following RF excitation. Imagine one simple mode, near a gadolinium ion (Gd3+), there is one water...
Nuclear magnetic resonance!
Hello all,i was studying about nuclear magnetic resonance,what i came to know is the study of nucleus in presence of magnetic field and then considering the possible states. But sir/madam what i don't understand here is using the word "RESONANCE". What it signifies...
Homework Statement
Nuclear magnetic resonance in water is due to the protons of hydrogen. Find the field necessary to produce NMR (nuclear magnetic resonance) at 60 MHz.
Homework Equations
These are the equations I think I'm supposed to use:
omega (subscript zero) = gamma * B...
NMR rf Field
hi all,
could anyone help me explain how the rf B1 field in an NMR spectrometer works? Especially the mechanism it uses to flip the net magnetisation by an angle of 90 or 180 degrees?
Would be very gratefull for a link or and explanation to this.
Thanks
Wadings
Hi,
I'm taking a course on medical imaging (mainly MRI), and I'm having trouble understanding NMR. Can anyone explain what this is all about in plain language? Here is what I make of it: Odd-numbered nuclei possesses a total spin of magnitude 1/2 and an associated magnetic moment (why is...
I've been reading about nuclear magnetic resonance, and one aspect is bothering me. (I haven't studied quantum physics yet.)
Quantum mechanically, the proton has only 2 energy states: spin +1/2 spin and spin -1/2. In NMR, a pulse of electromagnetism is applied to alter the orientation of the...