Dimensional relaxation

Our approach is to use the two-dimensional relaxation and diffusion correlation experiments to further enhance the resolution of different components. It is important to note that the correlation experiment, e.g., the Ti-T2 experiment, is different from two experiments of and T2 separately. For instance, the separate Ti and T2 experiment, in general, cannot determine the T1(/T2 ratio for each component. On the contrary, a component with a particular Tj and T2 will appear as a peak in the 2D 7i-T2 and the Ti/T2 ratio can be obtained directly. For example, small molecules often exhibit rapid rotation and diffusion in a solution and Ti/T2 ratio tends to be close to 1. On the other hand, the rotational dynamics of larger molecules such as proteins can be significantly slow compared with the Larmor frequency and resulting in a Ti/T2 ratio significantly larger than 1. 

As for inverse-detected one-dimensional relaxation measurements, there are problems related to the removal of proton signals originating from H not bound to C nuclei and to the fact that the H spectrum is in general... 

Hajduk, P. J., et al., One-dimensional relaxation- and diffusion-edited NMR methods for screening compounds that bind to macromolecules. J Am ChemSoc, 1997,119,12257-12261. 

In the case of one-dimensional relaxation, strain remains constant and temperature variation 0n also becomes a constant in a homothermous state. With condition of 0=0 when r=0, the third term on... 

ABSTRACT. A general theory for the propagation characteristics of the capillary wave on gas-liquid interface, where the physco-chemical equilibrium exists, was proposed on the basis of the two-dimensional relaxation theory and the surface thermodynamics. 

One-dimensional relaxation experiments were carried out at the critical iodide concentration and different values of Rq. Each perturbation consisted of a... 

We elose with tliree eonnnents. First, there is preliminary work on retrieving not only the amplitude but also the phase of photon eehoes [49]. This appears to be a promising avenue to aequire eomplete 2-dimensional time and freqiieney infonnation on the dynamies, analogous to methods tliat have been used in NMR. Seeond, we note that there is a growing literature on non-pertnrbative, niimerieal simulation of nonlinear speetroseopies. In these methods, the eonsisteney of the order of interaetion with the field and the appropriate relaxation proeess is aehieved automatieally. 

Gallagher Feeder S M and Jonas D 1999 Two-dimensional electronic correlation and relaxation spectra theory and model calculations J. Phys. Chem. A 102 10 489-505... 

Most metal surfaces have the same atomic structure as in the bulk, except that the interlayer spaciugs of the outenuost few atomic layers differ from the bulk values. In other words, entire atomic layers are shifted as a whole in a direction perpendicular to the surface. This is called relaxation, and it can be either inward or outward. Relaxation is usually reported as a percentage of the value of the bulk interlayer spacing. Relaxation does not affect the two-dimensional surface unit cell synuuetry, so surfaces that are purely relaxed have (1 x 1) synuuetry. 

Surface states can be divided into those that are intrinsic to a well ordered crystal surface with two-dimensional periodicity, and those that are extrinsic [25]. Intrinsic states include those that are associated with relaxation and reconstruction. Note, however, that even in a bulk-tenuinated surface, the outemiost atoms are in a different electronic enviromuent than the substrate atoms, which can also lead to intrinsic surface states. Extrinsic surface states are associated with imperfections in the perfect order of the surface region. Extrinsic states can also be fomied by an adsorbate, as discussed below. 

Barbate G, Ikura M, Kay L E, Pastor R W and Bax A 1992 Backbone dynamics of calmodulin studied by N relaxation using inverse detected two-dimensional NMR spectroscopy the central helix is flexible S/oefrem/sf/ y 31 5269-78... 

A good introductory treatment of the density operator formalism and two-dimensional NMR spectroscopy, nice presentation of Redfield relaxation theory. 

Crimp. The tow is usually relaxed at this point. Relaxation is essential because it gready reduces the tendency for fibrillation and increases the dimensional stabiUty of the fiber. Relaxation also increases fiber elongation and improves dye diffusion rates. This relaxation can be done in-line on Superba equipment or in batches in an autoclave. Generally saturated steam is used because the moisture reduces the process temperatures required. Fiber shrinkage during relaxation ranges from 10 to 40% depending on the temperature used, the polymer composition used for the fiber, and the amount of prior orientation and relaxation. The amount of relaxation is also tailored to the intended apphcation of the fiber product. 

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