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In this article, a recently published procedure for product design is applied to the design of carpet deodorizers/disinfectants and expanded to include multiple competitors. The procedure proposes to make a connection between consumer preferences in different markets, plant design, and supply-chain limitations to the characteristics of the product. Exploiting this connection, the procedure proposes to add a price-demand model and maximize the profit by simultaneously changing product characteristics and product price in each market. A consumer-preference model based on disinfectant effectiveness, scent type and intensity, fragrance duration, toxicity, and odor elimination properties was developed to assess consumer choices. Finally, the aforementioned consumer properties are linked to the product basic design parameters, such as slow-release particle diameter, fragrance content, proportion of ingredients, etc. The best product from the consumer point of view turns out not to be the most profitable. This well-known fact from practical experience can now be quantified, and a formal procedure to manage it is available.

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Complex fluids containing crystallizing fatty acids are important for consumer care products. The key features of these materials are their ability to support their weight under gravity due to the formation of a fatty acid crystal network, and to yield or flow beyond a critical applied strain. In model formulations comprised of two synthetic surfactants and a fatty acid in water, we have shown that the fatty acid crystal network consists of crystal aggregates linked by a non-crystallized mixed fatty acidsurfactant mesophase. We hypothesize that this mixed surfactant-fatty acid mesophase is critical for the macroscopic stability of the formulations. Rheological measurements combined with differential scanning calorimetry (DSC), X-ray scattering, and polarized light microscopy (PLM) measurements show the importance of surfactant loading on the overall stability of the formulations by linking morphology to rheology. Macroscopically homogeneous formulations are realized with 7-10 wt% of fatty acid. Increasing the fatty acid content without adding surfactant leads to inhomogeneous, phase separating formulations. Although both stable and unstable formulations show the presence of a surfactant-fatty acid mixed phase, a critical loading of surfactants is found to be necessary to create macroscopically homogenous formulations. We demonstrate how the rheology, microstructure and the macroscopic stability can be tuned by varying the relative amounts of surfactants and fatty acid.

An arterial stenosis, or a constriction of an artery, can lead to higher pressure losses than those seen in a healthy artery which, in turn, can disrupt normal functioning of the body. Depending on the type, size, and location of a stenosis, the decision to intervene might be made. Because many arterial stenoses can be characterized by improved medical imaging, insights into the effects of stenosis geometry on pressure loss could provide important information for medical decision making. Computational fluid dynamics (CFD) provides a means of relatively quick investigation of various stenotic artery geometries. In this work, CFD simulations varying axial location of a stenosis, stenosis eccentricity, stenosis percent occlusion, and shape were performed. The simulated arteries were models of pathologic human renal arteries. The results indicate that pressure loss across a stenosis has no dependence on stenosis eccentricity. Pressure loss was shown not to be affected significantly by the axial location of the stenosis, but it was affected strongly by the stenosis structure. The most significant dependence was on percent stenosis; simulations indicated a critical percent stenosis of approximately 75-80%, above which pressure loss increases drastically. The critical percent stenosis identified here is consistent with guidelines used by physicians.