PROCESSING AND ADDITIVE PERFORMANCE

The carbonation process can be either continuous or batch processes and is performed in two steps. In the first step, the sludge is separated. In the second step, further addition of carbon dioxide removes the excess lime, which is left in solution. The resulting solution is called thin juice. 

The operation of the clinical laboratory can be viewed as a series of processes, each of which has potential sources of error. Table 19-1 shows the processes that take place from the time of the physician s initial request for a test to the time of the final interpretation of the test result. This systems analysis identifies the critical processes for a typical laboratory however, each laboratory situation is somewhat different, and there may be additional processes and additional sources of error. It is important for each laboratory to perform a... 

It is important to include the full life cycle. A good recent example is the case of methyl terf-butyl ketone (MTBE). MTBE can be produced using an efficient catalytic distillation process and it performs well as a fuel additive. However, the combination of three facts [carcinogenic potency, significant solubility in water and difficulty in... 

PVC formulations include a large number of additives performing essential functions during their processing and regulating performance properties of final products. In the separate sections of this chapter, various groups of additives are briefly discussed to show their major types, typical concentrations, reasons for addition, most important properties, and their essential mechanisms of action. 

It should be noted that there is not simply an addition of thermotropic LCPs into fiber-reinforced plastics to get in situ hybrid composites. Bafna et al. used glass fibers to decrease the anisotropy of LCP fibril-reinforced polyetherimide [136]. He et al. improved the processability and mechanical performances of glass fiber-reinforced polypropylene by the addition of LCPs [159]. However, these two works did not actively and purposely generate a reinforced composite with the reinforcements having their diameters at two orders of magnitude. The key point for in situ hybrid composites is the formation of LCP fibrils in the material system. As a combination of in situ composite and hybrid fiber reinforcing, the fabrication of in situ hybrid composites utilizes fabrication... 

The rheology of liquid crystal polymers was reviewed by Wissbrun. A more recent review is from 1996, ° particularly Chapter 4 by Cogswell and Wissbrunn, which makes the point that LCP changes the rules which govern the balance between ease of processing and service performance compared to conventional thermoplastics reinforced by the addition of discrete fiber fillers. These reviews describe the essential features of the usual response of thermotropic polymers to shear, namely shear-thinning. 

Since process design starts with the reactor, the first decisions are those which lead to the choice of reactor. These decisions are among the most important in the whole design. Good reactor performance is of paramount importance in determining the economic viability of the overall design and fundamentally important to the environmental impact of the process. In addition to the desired products, reactors produce unwanted byproducts. These unwanted byproducts create environmental problems. As we shall discuss later in Chap. 10, the best solution to environmental problems is not elaborate treatment methods but not to produce waste in the first place. 

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