Mechanisms and anomalies

VIII. Theoretical Interpretation of Viscoelastic Mechanisms and Anomalies... 

VIII. THEORETICAL INTERPRETATION OF VISCOELASTIC MECHANISMS AND ANOMALIES... 

Mann, A.W., Birrell, R.D., Fedikow, M.A.F., de Souza, H.A.F. 2005. Vertical ionic migration mechanisms, soil anomalies, and sampling depth for mineral exploration. Geochemistry - Exploration, Environment, Analysis, 5, 201-210. 

Although there are some anomalies in the literature, it is generally agreed that both types of volume deformation are a function of the same fundamental mechanism and that the influence of other factors such as admixtures will affect both shrinkage and creep in a similar manner. As outlined earlier, water-reducing admixtures can be used to obtain different effects on the plastic/hardened concrete and it is this factor, together with the admixture type, that is important in determining the effect on the volume deformations of concrete. 

Ashmore and Levitt12-281 found the reaction anomalously fast in the early stages of the reaction (before 10% decomposition). This anomaly was not altered by adding large excesses of inert gas and was also shown not to be caused by reactions of NOz with grease or diffusion into the dead space outside the reaction vessel. It was eliminated by adding equal pressures of NO. The effect was attributed to the existence of parallel paths for the decomposition of N02 one was the usual molecular mechanism, and the other was a free-radical mechanism... 

Fetal microcephaly has been attributed to cocaine abuse during pregnancy (323). Urine toxicology confirmed the presence of morphine, benzoylecgonine, barbiturates, paracetamol, and propoxyphene. Analyses of amniotic fluid, placenta, and fetal serum and urine were also positive for these substances. The authors suggested that vascular disruption was the likely major mechanism of anomalies, both behavioral and malformative, due to prolonged exposure to cocaine in utero. 

DMA analysis substantiated the possible morphological features that could partially account for the trend in mechanical and fracture properties of the glass laminate composites [146]. The DMA, done at a frequency of 1 Hz, are given in Fig. 12, where the percentage retention of the room temperature storage modulus (E ) is plotted as a function of temperature to normalize the anomalies resulting from differences in resin content for different systems. EPOBAN-modified... 

In this section, we introduce what is essentially an equivalent model to the one described in Sec. 2.5.2. This model, referred to as the primitive cluster model, has several features that make it more useful in the study of the molecular mechanism underlying the anomalous behavior of liquid water and aqueous solutions. For water, as we shall see below, the two models provide essentially the same results. However, with the cluster model, we can get a deeper insight into the mechanism underlyingthe anomalies of water, namely the structural changes (here, essentially the change in the cluster-size distribution) in the liquid that lead to the anomalous behavior. As we shall see in Sec. 3.9, the cluster model is also more convenient for the study of some of the most outstanding properties of aqueous solutions of simple solutes. 

CD intensity from this source vanishes in random orientation leaving only that from the El-Ml mechanism, the anomaly is explained. Some evidence in support of this explanation came from the phase modulated orthoaxial spectrum reported by Jensen and Galsbol. Final confirmation came from the recent ab initio calculation where both the El-Ml and E1-E2 contributions to the CD were calculated and found to be of the same sign and comparable magnitudes. 

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