Rough surface sinusoidal

Surface of TPE samples irradiated to 500 kGy showed two types of cracks — a number of broad cracks interconnected by a network of microcracks. Thomas etal. [1986] attributed these to embrittlement of the bulk as a result of cross-linking, and to radiation-induced surface oxidation. The tear failure surface of non-irradiated TPE showed a rough surface with sinusoidal foldings and closely spaced vertical striations. The development of these patterns was attributed... 

Fig. 3 Scanning electron microscope images of blood vessels in normal tissues and blood vessels of tnmor. Normal capillary of the pancreas (A), colon (intestinal villi) (B), and liver (sinusoid) (C), and enlarged image of blood capillary of normal liver (D) are shown. (E) Metastatic tumor nodule (area ) in the normal liver is shown. (F) Tumor vessels at capillary level (larger magnification) and showing rough surface, and early phase of extravasating vessels (shown by arrows). No leakage of polymer is seen in normal tissues (A-D), whereas tumor-selective extravasation of polymer (by EPR effect) is seen clearly in the tumor nodule (E)...

The model for rough surface ehl which has been adopted in our initial studies is described in detail elsewhere (2). Only a brief description is given here. The model consists of a circumferentially-grooved roller running in lubricated contact with a smooth roller. The grooves are assumed to be sinusoidal in profile but the numerical analysis is not restricted to this simple shape. The situation is illustrated schematically in Figure 1. 

Assuming an idealized rough surface, consisting of concentric patterns of sinusoidal corrugations (Figure 14.18a), one may simply relate the apparent contact angle 9 to that on a smooth surface 9° by Eq. (14.120),... 

In this section we extend previous studies of surfaces with sinusoidal concentric grooves to the more general case of an axially or cylindrically symmetric rough surface of arbitrary profile. Gravity is neglected. The entire system has the same symmetry as the solid surface and in the case of cylindrical symmetry there is a plane of symmetry such that the triple line contacts identical regions of the solid on the two sides. 

Another important feature of polymer adsorption is the influence exerted on it by the surface roughness. Ball et al. [22] proposed that if the surface potential is not attractive enough to bind the polymer when flat, then corrugation can aid binding as follows. For a sinusoidal corrugation, one might anticipate that some... 

Results obtained in [80,82] show that the influence of slight surface roughness on the frequency shift cannot be explained in terms of the mass of liquid trapped by surface cavities, as proposed in [76,77]. This statement can be illustrated by consideration of the sinusoidal roughness profile. The mass of the liquid trapped by sinusoidal grooves does not depend on the slope of the roughness, h/l, and is equal to S h, where S is the area of the crystal. However, Eq. 33 demonstrates that the roughness-induced frequency shift does increases with increasing slope. 

The effect of roughness on the wettability of an idealized sinusoidal surface has been studied with a digital computer. The equations of Wenzel and of Cassie and Baxter are discussed in relation to the model. The heights of the energy barriers between metastable states of a drop are seen to be of utmost importance in determining the magnitude of contact angle hysteresis. 

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