Films of pure poly(vinyl alcohol) (PVA) and samples doped with di€erent concentrations of heptahydrated ferrous sulphate were prepared using a casting method. Mechanical and relaxation properties were measured before and after irradiation. The modulus of elasticity, yield strength, tensile strength ductility and relaxation time were produced from true stress±true strain and stress relaxation me...

Reconstruction of the kinetics of relaxation processes induced in a medium by laser radiation is considered. Implementation of a-regularization algorithm of the ill-posed problem solution in optoacoustic (OA) diagnostics of liquids is discussed. The relationship between parameters of the diagnostic experimental set-up and the frequency band where relaxation spectra can be restored is establishe...

The present study investigates magnetohydrodynamic flow and heat transfer of a Maxwell fluid using a spectral relaxation method. The method is based on simple iteration schemes formed by reduction of the order of the momentum equation followed by a rearrangement of the resulting governing nonlinear equation systems which are then solved using spectral methods. The effect of the flow parameters ...

We show that the prediction of (15)N relaxation rates in proteins can be extended to systems with anisotropic global rotational diffusion by using a network of coupled rotators (NCR), starting from a three-dimensional structure. The relaxation rates predicted by this method are confronted in several examples with experiments performed by other groups. The NCR spectral density functions are comp...

2014 Relaxational modes of short range chain fluctuations in concentrated polymer solutions are investigated by studying the proton magnetic relaxation rates. The relaxation rate in the rotating frame and the spin-lattice relaxation rate observed in polyisobutylene chains are found to be independent of the molecular weight in the range 5 x 104 to 106. They are governed by a mechanism which is a...

AIM Cardiac magnetic resonance (CMR) can visualize inflammatory tissue changes in acute myocarditis. Several quantitative image-derived parameters have been described to enhance the diagnostic value of CMR, but no direct comparison of these techniques is available. METHODS AND RESULTS A total of 34 patients with suspected acute myocarditis and 50 control subjects underwent CMR. CMR protocol i...

In a previous paper (Hilton & Yi 1992), a systematic study was undertaken to determine how shapes of relaxation–time functions affect damping characteristics of isotropic viscoelastic materials. The significant parameters were the instantaneous and fully relaxed moduli (Regions A and E on Fig. 1), the two “knees” (B and D), the central slope (C) and anisotropic shift functions. The sensitivity ...

background: cardiac syndrome x is a relatively common disorder, and still not much is known about the causative factors or its pathophysiology, which makes it difficult to cure. due to its chronic nature and debilitating symptoms, many patients have significantly reduced quality of life (qol).the purpose of this study was to assess the impact of phase iii cardiac rehabilitation (cr) and relaxat...

A natural bond orbital (NBO) analysis of unpaired electron spin density in metalloproteins is presented, which allows a fast and robust calculation of paramagnetic NMR parameters. Approximately 90% of the unpaired electron spin density occupies metal-ligand NBOs, allowing the majority of the density to be modeled by only a few NBOs that reflect the chemical bonding environment. We show that the...