Ingredient interaction example

There is a point when the NMR characteristics of a bulk polymer have to be treated as non-liquid-like, that is below the glass transition temperature. The NMR spectrum will then be dominated by static effects, such as the orientation dependence of chemical shift and the dipolar interaction. The earliest forms of solid-state polymer NMR were developed in the knowledge that these solid-state effects would be present, and would complicate the resulting data interpretations. Proton NMR studies of polymers have an impressive pedigree, and have relied on applications of a distinct solid-state theory. But it is only relatively recently that aspects of this theory have been refined to the point where experimental observations can be understood more fully. In particular, the process of spin diffusion is much better appreciated. Proton broad-line NMR does not necessarily require the use of large magnets and despite the theoretical uncertainties it has been widely accepted within the realms of rapid analysis. In its simplest form it has been used to quantify liquid and solid ingredients, for example, in plasticised polymers. 

Manufacturers who wish to add some, but not all, ingredients found in human milk may defeat the purpose of the added nutrients or may potentiate negative interactions. Examples include the deleterious effect on growth when eicosapentaenoic acid is added without adequate DHA (Carlson et al., 1996) and the potential negative effect of adding polyunsatu-... 

The active ingredients in a shampoo play three fundamental roles. Some allow water to wash away the substances that make hair dirty. Others adhere to hair to impart a desirable feel and texture. The rest are emulsifiers that keep the mixture from separating into its components. To accomplish these effects, ingredients combine two types of interactions a strong attraction to water (hydrophilic) and an aversion to water (hydrophobic). It may seem that these properties are incompatible, but shampoos contain molecules that are designed to be simultaneously hydrophilic and hydrophobic. One example is sodium lauryl sulfate, our inset molecule. The ionic head of the molecule is hydrophilic, so it interacts attractively with water. The hydrocarbon tail is hydrophobic, so it interacts attractively with grease and dirt. Molecules of the shampoo associate with hydrophobic dirt particles to form hydrophilic clumps that dissolve in water and wash away. 

Chemical compound homogeneity is an important issue for pharmaceutical sohd forms. A classical spectrometer integrates the spatial information. In solid form analysis, use of a mean spectrum on a surface can be a drawback. For example, in the pharmaceutical industry it is important to map the distribution of active ingredients and excipients in a tablet so as to reveal physical interaction between the compounds and help to solve homogeneity issues. Spectroscopic imaging techniques that visualize chemical component distribution are thus of great interest to the pharmaceutical community. 

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