Rapid evaluation processes

The Fauske and Associates Reactive System Screening Tool (RSST) was developed as a result of the DIERS studies and allows rapid evaluation of the potential for runaway reactions. It measures the rate of energy and gas release during the runaway and is valuable for screening various process systems before commercial designs are completed (see Figure 7-61). 

Figure 4.37. Build-up of a decomposition product over time. Two climatic conditions were evaluated The higher the temperature, the more rapid the process.

Instead of using repeated solution of a suitable eigenvalue equation to optimize the orbitals, as in conventional forms of SCF theory, we have found it more convenient to optimize by a gradient method based on direct evaluation of the ener functional (4), ortho normalization being restored after every parameter variation. Although many iterations are required, the energy evaluation is extremely rapid, the process is very stable, and any constraints on the parameters (e.g. due to spatial symmetry or choice of some type of localization) are very easily imposed. It is also a simple matter to optimize with respect to non-linear parameters such as orbital exponents. 

In each of the preceding studies, one major advantage of the near-IR technique is the rapid evaluation of the sample without the need for traditional extraction techniques and subsequent chromatographic or colorimetric analysis. For this reason, near-IR is an ideal form of analysis in a quality control, or on-line, process analysis environment. In a complementary mid- and near-IR... 

DRIFT-IR) spectroscopy was also used for polymorphic characterization. The authors detail the application of multivariate techniques, multivariate statistical process control (MSPC), PC A and PLS, to the spectroscopic data for a simple yet powerful, rapid evaluation of the given crystalhzation process. ... 

Documented process structure provides rapid employee assimilations when transferring employees between sites. New employees, replacing existing process owners, are enabled to rapidly execute process responsibilities due to the abbreviated learning curve when processes have been well defined and documented. Systems designed as described here provide meaningful and comparable metrics for leadership to evaluate progress, compliance, and performance. 

The Bose group s prolific applications of the microwave-assisted ketene-imine annelation process suggest that research laboratories everywhere should be able to justify acquisition of microwave equipment to accelerate research programs via the rapid preparation of a variety of new structures. In a process development setting, the microwave technique should find application in the rapid evaluation and optimization of process parameters, such as solvent, reaction concentration (and neat reactions), temperature, time, pressure, the structure of catalyzing bases/acids, rates of addition, and so on. 

Problems that exist when evaluating processes can take into consideration factors such as insufficient compaction and consolidation before plastic solidification or cure occurs before air pockets develop, incomplete or uncontrollable wet-out and encapsulation of the fibers, and/or insufficient fiber or uniform fiber content. These deficiencies lead to loss of strength and stiffness and susceptibility to deterioration by water and aggressive agents. Heat control may not be adequate particularly for crystalline plastics or it may be too rapid (Chapter 1). 

The atom utilization [13-18], atom efficiency or atom economy concept, first introduced by Trost [21, 22], is an extremely useful tool for rapid evaluation of the amounts of waste that will be generated by alternative processes. It is calculated by dividing the molecular weight of the product by the sum total of the molecular weights of all substances formed in the stoichiometric equation for the reaction involved. For example, the atom efficiencies of stoichiometric (Cr03) vs. catalytic (02) oxidation of a secondary alcohol to the corresponding ketone are compared in Fig. 1.1. 

The results presented above illustrate the utility of using AW frequency transients to evaluate diffusional processes in thin polymer films. The ability to use thin films allows the rapid evaluation of D values from 10 to 10 cm /sec... 

The preceding results show that the ability of AW devices to follow the transient uptake of a species into a thin film allows these devices to be used to probe a wide variety of diffusional processes. As described for Fickian diffusion, a significant advantage of the AW technique is the ability to use thin films, which results in the rapid evaluation of the diffusional properties even in polymers that exhibit very slow transient uptake. 

DNA and protein microarray technology has revolutionized the way scientists study complex biological processes. These arrays consist of thousands of nucleic acids or proteins immobilized on a solid support. The array format allows one to rapidly evaluate interactions with a large number of molecules simultaneously. For example, one can examine the expression profiles of thousands of genes in a single experiment. 

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