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Rheological character

StabiHty (dilution, mechanical, shear, freeze—thaw, heat, bacterial) compatibiHty (plasticizers, thickeners, pigments, extenders, coalescing agents) rheological character... [Pg.468]

For conventional wet processing of sheet steel, the porcelain enamel frit is ball-milled using clay, certain electrolytes, and water to form a stable suspension. This clay-supported slurry of small particles is called the sHp and has the consistency of a heavy cream. The ingredients of the mill batch are carefully controlled. The amount and purity of all materials in the mill, including the clay and water, affect the rheological character of the sHp as well as a number of the properties of the fined enamel such as chemical resistance, reflectance, gloss, color, and abrasion resistance. [Pg.209]

The measurements are carried out at preselected shear rates. The resulting curves are plotted in form of flow-curves t (D) or viscosity-curves ti (D) and give information about the viscosity of a substance at certain shear rates and their rheological character dividing the substances in Newtonian and Non-Newtonian fluids. [Pg.409]

The term semisolid infers a unique rheological character. Like solids, such systems retain their shape until acted upon by an outside force, whereupon, unlike solids, they are easily deformed. Thus, a finger drawn through a semisolid mass leaves a track that does not fill up when the action is complete. Rather, the deformation made is for all practical purposes permanent, an outcome physically characterized by saying semisolids deform plastically. Their overall rheological properties allow them to be spread over the skin to form films that cling tenaciously. [Pg.220]

Semisolids dosage forms, as a class, are plastic in behavior, i.e., they retain their shape until acted upon by an outside force, in which case they deform and the deformations are permanent. The common denominator to all semisolid systems which gives them their special rheological character is that they all have a permanent three-dimensional structure. This structure is sufficient when undisturbed to impart solid-like properties but which is easily broken down and realigned under some strain or applied force (4). The semisolid systems used pharmaceutically include... [Pg.197]

Measurement of linear viscolelastic properties is a useful way of gaining information about a food s micro structure and how this influences the food s rheological character (Narine and Marangoni, 1999 Gunsekaran and Ak, 2002). However, many processing operations, and mastication, involve large, rapid deformations during which viscoelastic behavior is nonlinear. [Pg.760]

Edwards and Wasan [17] and Prud homme and Khan [18] have indicated that many of the reported rheological measurement do not truly or uniquely represent the rheological character of foams. For example, the effective viscosity is proved to depend on the geometry parameters of the devices, often the slip of a foam along the wall is not considered (or is... [Pg.585]

Rheological character bubbles high yield spherical cap apparent viscosity small indentation apparent viscosity apparent viscosity... [Pg.121]

Brandsma, R.L. and Rizvi, S.S.H., Effect of manufacturing treatments on the rheological character of mozzarella cheese made from microfiltration retentate depleted of whey proteins, Int. J. Food Sci. TechnoL, 36, 601, 2001. [Pg.667]

The term semisolid infers a unique rheological character. Like solids, such systems retain their shape until acted upon by an outside force, whereupon, unlike solids, they are easily... [Pg.71]

Because of the nature of foams, the rheological character of foam fluids is difficult to quantify. The viscosity of foams is primarily dependent upon foam quality and external-phase fluid viscosity. Stimulation fluids are subjected to pressure variations from surface to downhole conditions therefore, foam quality and viscosity will change accordingly. In order to overcome the changing conditions experienced during stimulations, the foam fluids are designed to reach a specified quality at downhole conditions. [Pg.383]

Bore et al. [154] found that the structures of the Qg fatty acids of oily and dry hair differ. For subjects with dry hair, the predominant isomer is octadecenoic acid (oleic acid), whereas for subjects with oily hair 8-octadecenoic acid was the predominant isomer. Thus, oily hair is different from dry hair in its chemical composition and in its rheological character. [Pg.95]

Although flow mechanics are determined by their physical surroundings in more watery fluids, it is a substance s rheologic character which essentially determines flow characteristics among the more viscous and viscoelastic substances (Fig. 8). [Pg.8]

Gao, H.W. and French, T.R. Optimal Rheological Character in Dynamic Stability of Polymer Flow Through Porous Media, NIPER-303 (DE88001225), U.S. DOE, Washington, DC (April 1988). [Pg.89]


See other pages where Rheological character is mentioned: [Pg.105]    [Pg.224]    [Pg.9]    [Pg.468]    [Pg.301]    [Pg.226]    [Pg.51]    [Pg.149]    [Pg.406]    [Pg.70]    [Pg.22]    [Pg.242]    [Pg.105]    [Pg.473]   
See also in sourсe #XX -- [ Pg.406 ]




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