English
Related papers

Related papers: Describe NMR relaxation by effective diffusion equ…

200 papers

This paper employs the general time-space fractional diffusion equation to derive correlation time function for analyzing nuclear magnetic resonance (NMR) relaxation. Both the anomalous rotational and translational diffusion are treated.…

Chemical Physics · Physics 2018-12-31 Guoxing Lin

This paper proposes an effective phase diffusion method to analyze chemical exchange in nuclear magnetic resonance (NMR). The chemical exchange involves spin jumps around different sites where the spin angular frequencies vary, which leads…

Chemical Physics · Physics 2023-07-19 Guoxing Lin

A wide variety of nuclear magnetic resonance experiments rely on the prediction and analysis of relaxation processes. Recently, innovative approaches have been introduced where the sample travels through a broad range of magnetic fields in…

We consider a quasiclassical model that allows us to simulate the process of spin diffusion and relaxation in the presence of a highly nonuniform magnetic field. The energy of the slow relaxing spins flows to the fast relaxing spins due to…

Materials Science · Physics 2009-11-10 G. P. Berman , B. M. Chernobrod , V. N. Gorshkov , V. I. Tsifrinovich

The general theoretical description of spin self-diffusion under nonlinear gradient is proposed, which extends the effective phase diffusion method for linear gradient field. Based on the phase diffusion, the proposed method reveals the…

Chemical Physics · Physics 2024-05-30 Guoxing Lin

Application of fractional calculus to the description of anomalous diffusion and relaxation processes in complex media provided one of the most impressive impulses to the development of statistical physics during the last decade. In…

Soft Condensed Matter · Physics 2008-11-13 A. E. Sitnitsky

We consider the NMR signal from a permeable medium with a heterogeneous Larmor frequency component that varies on a scale comparable to the spin-carrier diffusion length. We focus on the mesoscopic part of the transverse relaxation, that…

Mesoscale and Nanoscale Physics · Physics 2008-10-23 D. S. Novikov , V. G. Kiselev

The theory of spin diffusion is extended to the case of spin lattice relaxation and spin diffusion in an inhomogeneous field in spin systems with non-equidistant energy spectrum. Two coupled equations describing the mutual relaxation and…

Materials Science · Physics 2007-05-23 Gregory B. Furman , Shaul D. Goren

Dynamic nuclear polarization (DNP) is a promising strategy for generating a significantly increased non-thermal spin polarization in nuclear magnetic resonance (NMR) applications thereby circumventing the need for strong magnetic fields.…

Quantum Physics · Physics 2015-07-15 Alexander Karabanov , Daniel Wisniewski , Igor Lesanovsky , Walter Köckenberger

We consider nuclear spin-lattice relaxation rate resulted from a fractional diffusion equation for anomalous rotational wobbling in a cone. The mechanism of relaxation is assumed to be due to dipole-dipole interaction of nuclear spins and…

Statistical Mechanics · Physics 2011-06-30 A. E. Sitnitsky

We demonstrate theoretically and numerically how to control the NMR relaxation rate after application of the standard spin echo technique. Using radiation damping, we return the nuclear magnetization to its equilibrium state during a time…

Instrumentation and Detectors · Physics 2011-12-01 Gennady P. Berman , Michelle A. Espy , Vyacheslav N. Gorshkov , Vladimir I. Tsifrinovich , Petr L. Volegov

The magnetic interactions between the spin of an unpaired electron and the surrounding nuclear spins can be exploited to gain structural information, to reduce nuclear relaxation times as well as to create nuclear hyperpolarization via…

A method is developed for solving nonlinear systems of differential, or integrodifferential, equations with stochastic fields. The method makes it possible to give an accurate solution for an interesting physical problem: What are the…

Statistical Mechanics · Physics 2009-10-30 V. I. Yukalov

Numerical modelling of coherent spin relaxation in nanomagnets, formed by magnetic molecules of high spins, is accomplished. Such a coherent spin dynamics can be realized in the presence of a resonant electric circuit coupled to the magnet.…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 V. I. Yukalov , V. K. Henner , P. V. Kharebov

Monte Carlo simulations are used to study the magnetic relaxation of a system of single domain particles with dipolar interactions modeled by a chain of Heisenberg classical spins. We show that the so-called $T\ln(t/\tau_0)$ method can be…

Materials Science · Physics 2007-05-23 Oscar Iglesias , Amilcar Labarta

The phase time coupling effect on NMR relaxation is investigated based on coupled and uncoupled phase diffusion. The results indicate that phase and time coupling could significantly impact the NMR relaxation time. The spectral density term…

Chemical Physics · Physics 2023-09-27 Guoxing Lin

Nuclear Magnetic Resonance (NMR) is a tool of choice to characterize molecular motions. In biological macromolecules, pico- to nano-second motions, in particular, can be probed by nuclear spin relaxation rates which depend on the time…

Chemical Physics · Physics 2022-10-12 Nicolas Bolik-Coulon , Fabien Ferrage

Nuclear magnetic resonance (NMR) is a widely used nondestructive method to study random motion of spin-bearing particles in different systems. In the long-time limit the theoretical description of the NMR experiments is well developed and…

Statistical Mechanics · Physics 2018-03-06 Vladimir Lisy , Jana Tothova

A general expression is derived for the dipolar NMR spin-lattice relaxation rate $1/T_1$ of a system exhibiting Brownian dynamics in a discrete and finite configuration space. It is shown that this approach can be particularly useful to…

Chemical Physics · Physics 2015-07-07 P. Wzietek

Distant dipolar field (DDF)-based nuclear magnetic resonance is an active research area with many fundamental properties still not well understood. Already several intriguing applications have developed, like HOMOGENIZED and IDEAL…

Medical Physics · Physics 2009-09-29 Curtis Andrew Corum
‹ Prev 1 2 3 10 Next ›