T2

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T2

In magnetic resonance, the time for 63% of transverse relaxation to occur; the value is a function of magnetic field strength and the chemical environment of the hydrogen nucleus; for protons in fat and in water, in a 1.5T magnet, about 60 milliseconds and 250 milliseconds, respectively. A T2-weighted image will have a bright water signal.

T2*

The effective T2 relaxation time, shorter than T2 because of magnetic field inhomogeneities; the observed time constant of free induction decay. In gradient echo images, contrast depends on T2*, whereas in sequences with a 180° rephasing pulse, the contrast depends on T2.
[tē-tū'stăr]

T2

An MRI term for the time constant at which phase coherence among spins oriented at an angle to the static magnetic field is lost due to interactions between the spins, resulting in a loss of transverse magnetisation and MRI signal.

T2

magnetic resonance The time for 63% of transverse relaxation to occur; the value is a function of magnetic field strength and the chemical environment of the hydrogen nucleus.
References in periodicals archive ?
For l = 0, there is spin-spin term which we will consider in the present work.
The four Ramsey terms, Fermi contact (FC), spin dipole (SD), diamagnetic spin orbit (DSO), and paramagnetic spin orbit (PSO), were used to determine the total nuclear spin-spin coupling (J) [85].
This is the long-range spin-spin interaction we are looking for," he stated.
Mariette, "NMR study of tomato pericarp tissue by spin-spin relaxation and water self-diffusion," Appl.
Moreover, the spin-spin couplings in the real materials often have additional contributions with the theoretical model being investigated.
The spectra evaluated from echoes 1-10 in comparison with those from echoes 1-21 help to estimate the impact of spin-spin relaxation on the spectral shapes and intensities.
A relaxacao spin-spin (T2) ocorre por meio da interacao de protons com os campos magneticos de outros nucleos e por causa das inomogeneidades inerentes a (Bo).
"If you tell a solid-state physicist, 'reduce your spin-spin interaction by a factor of two because I want to see the physics,' he can't do it," Schatz says.
The text contains about 280 structural problems employing major modern spectroscopic techniques, a selection of 18 problems using 2D-NMR spectroscopy, about 20 problems dealing with the interpretation of spin-spin coupling in proton NMR spectra, and eight problems based on the quantitative analysis of mixtures using proton and carbon NMR spectroscopy.
Spin-spin relaxation time [T.sub.1[rho]] was determined by measuring spin echoes (90[degrees]x - T - 180[degrees]y) under spin lock condition, with T sampling in the range of 60 [micro]s to 1 ms.
This condition is known in chemistry as "spin-spin coupling."
The ground State Hamiltonian [H.sup.Fp.sub.ground] is set up for a given value of the total angular momentum and parity and includes electrostatic interactions V(R) (the adiabatic Born-Oppenheimer potentials), the mechanical rotation operator [l.sup.2]/2[micro][R.sup.2], the radial kinetic energy operator, the spin-spin dipole interaction, and the atomic hyperfine Hamiltonians.