Homogeneous erosion

In bulk erosion, the entire area of polymer matrix is subject to chemical or enzymatic reactions, thus erosion occurs homogeneously throughout the entire matrix Accordingly, the degradation pattern is sometimes termed homogeneous erosion. 

A procedure for preparing a homogenous chitosan-amine oxide gel was reported [ 134]. The swelling behavior and release characteristics of the gel were studied in buffer solution (pH 7.4) at room temperature [135-137]. Homogeneous erosion of the matrix and nearly zero-order release of ampicillin trihydrate were observed [136]. The thermal properties of chitosan-amine oxide gel were also reported in subsequent studies [138]. 

However, it is important to distinguish two types of hydrolytic erosion of a solid, hydrophobic polymer. In one, referred to as homogeneous erosion, the hydrolysis occurs at a uniform rate throughout the matrix. In the other, called heterogeneous... 

The release of an active compound from a matrix-type delivery system may be controlled by a combination of diffusion and erosion. Heterogeneous erosion occurs when degradation is confined to a thin layer at the delivery system surface, whereas homogenous erosion is a result of degradation occurring at a uniform rate throughout the polymer matrix. 

Presumptions covalent networks of identical hydrophobicity, drug-polymer interaction, degrada-tion/homogeneous erosion pathway, size and morphology loaded by swelling (see text for deteiils)... 

Since the ultrasonic radiating surface is not in direct contact with the reaction solution, the acoustic intensities are much lower than those of the direct immersion horn, and so homogeneous sonochemistry is often quite sluggish. On the other hand, there is no possibility of contamination from erosion of the titanium horn. 

When describing erosion of and drug release from surface erodible polymers, it is often implicitly assumed that the matrix erodes uniformly, thus resulting in a uniform release profile for a homogenously dispersed drug. While this may be a valid assumption for some homopolymer systems, neglecting the effects of crystallinity, some multicomponent... 

Based on these results, it becomes necessary to install guide vanes to prevent flue gas flow stagnation at the corner as well as erosion of the far wall. The goal of this work is to deliver a well-mixed homogeneous flue gas stream to the inlet of the SCR catalyst. Angular entry of the flue gas into the SCR catalyst is avoided to protect the catalyst from erosion. 

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