Development processes physical

Quahtative simulation is a specific KBS model of physical processes that are not understood well enough to develop a physics-based numeric model. Corrosion, folding, mechanical wear, equipment failure, and fatigue are not easily modeled, but decisions about them can be based on qualitative reasoning. See Refs. 178 and 292. 

There is no unitpie articulable law or set of laws that any observer contained in the universe Q can const.ruct even in principle that describes it exactly. It therefore behooves us to develop a primal physics P that is maximally relativistic not in a gcnerically Einsteinian sense, but in an informational sense. That is, to develop a physics in which the meaning of any object or process exists only relative to something (ideally, everything) else. 

Physical models of commercial fluidized bed equipment provide an important source of design information for process development. A physical model of a commercial fluidized bed processor provides a small-scale simulation of the fluid dynamics of a commercial process. While commercial processes will typically operate at conditions making direct observation of bed fluid dynamics difficult (high temperature, high pressure, corrosive... 

Powder flow is most frequently thought of as relevant to formulation development, and there are numerous references attempting to correlate any one of a number of measures of powder flow to the manufacturing properties of a formulation [34—40]. In particular, the importance of physical properties in affecting powder flow has been well documented. Research into the effect of the mechanical properties on powder flow has, however, been very limited. It is, of course, important to be able to determine and quantitate the powder flow properties of formulations. It is of equal importance, however, to determine the powder flow characteristics of bulk drug early in the development process (preformulation phase). Often, the preformulation or formulation scientist is constrained by time, materials, and manpower. Yet certainly the preformulation studies carried out should be meaningful. Well-defined experimental methods and procedures should be used the information generated should be reproducible and permit useful predictions to be made. 

The second challenge is to relate the desired product attributes to the material properties of the ingredients and the structure of the product. For example, the development process would have been much more efficient if a model was available to describe the behavior of cleansing bars and structured food products. Without the benefits of predictive models, as is the present status for many consumer products, extensive trial-and-error by experiments are required. Even if a comprehensive model based on first principles is not available, a combination of physical insights and heuristics can still help improve the development process. Chapters 1-2 report some new developments in this area. See also [11] for a more detailed discussion on the issues and needs related to the roles and uses of property models in product design. 

The failure to lend itself to good quantitative modelling goes a long way toward explaining why unit processes ultimately failed to establish themselves permanently in the discipline. This failure was eventually of some importance because its causes were progressively recognized and identified. These causes involved insufficient development of physical chemistry, insufficient means of computation and the like. Moreover, the... 

At every stage of the development process, the results of a reaction or process stage will be analysed in one of two ways. The reaction mixture itself will be sampled and analysed to yield information such as extent/completion of reaction, reaction yield or reaction purity. Alternatively, the reaction product will be isolated and dried before sampling and analysis. Typical analytical information in this case would include both chemical and physical characterisation, plus quantitative data to ensure conformance with some pre-defined specification or to provide batch data on which a suitable specification will ultimately be based. Note that however quickly the analytical data are provided, there is a disconnect from the reaction, which means that reaction control is impossible and that... 

To account for the sharp drop in rate at the higher sulfite concentrations, it was suggested that the solvent action of the sulfite can isolate the latent image nuclei from the main body of the grains, so that development can proceed only by the slower physical development process. 

A recent development in physical techniques which may be of aid in evaluating the relative merits of theory is the Mossbauer effect. This effect is based upon recoilless y-ray emission (absorption) resulting from a nuclear transition in a particular atom with the resonance condition of zero-phonon processes. Since such nuclear transitions can be obtained with... 

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