Size organ plant

The process engineering requirements of plant cell, tissue or organ systems are quite different than those typically seen with bacteria or non-plant eukaryotic systems. The sizes of plant cells or cell aggregates, for example, are almost four orders of magnitude larger than a typical bacterial cell. Organized plant structures in culture are macroscopic and easily seen with the naked eye. The ability to handle effectively the variety of possible plant structures is a formidable task, but one which is necessary for successful commercial exploitation for chemicals production. 

Some examples of commercial active component production and production of substances with defined and uniform particle sizes (organic and inorganic materials) realized on pilot plant by using the RESS are given in Table 24.8. Other processes were also tested for synthesis of the particles with uniform size distribution as well as production of particles with specific structure (gas antisolvent recrystallization, GASR precipitation with a compressed antisolvent, PCA solution enhanced dispersion of solids, SEDS particles from gas-saturated solutions, PGSS) as shown in Table 24.9. All these processes are of special interest in pharmaceutical industry and in the production of different polymers. 

You would ejq)ect that most medium and larger sized chemical plants and refineries use electronic systems today either for partial of full evaluation It was not always that way. A 2001 survey by a leading university (9 years after the law went in to efiect) indicated that about 40% of the responding organizations still handled MOC creation, approval, and documentation in paper systems [11], (The details of the surv are in the next section.)... 

Natural resins are generally described as solid or semisolid amorphous, fusible, organic substances that are formed in plant secretions. They are usually transparent or translucent yeUow-to-brown colored, and are soluble in organic solvents but not in water. The principal uses for natural resins are in varnishes, printing inks, adhesives, paper size, and polymer compositions. The term natural resins includes tree and plant exudates, fossil resins, mined resins, and shellac. They often have been altered from their original state during isolation and processing. For some appHcations, the resins have been chemically modified to increase their industrial utiUty. 

The organization charts in Figures 1.1-1.4, adopted from real plant organizations of various sizes and in a variety of industries, illustrate some typical structures. 

The weathering process which eventually reduces the rock of the parent material to the inorganic constituents of soil comprises both physical and chemical changes. Size reduction from rocks to the colloidal state depends not only upon the mechanical action of natural forces but also on chemical solubilisation of certain minerals, action of plant roots, and the effects of organic substances formed by biological activity. 

The perceived sensitivity of plant cells to the hydrodynamic stress associated with aeration and agitation conditions is typically attributed to the physical characteristics of the suspended cells, namely their size, the presence of a cell wall, the existence of a large vacuole, and their tendency to aggregate. Table 1 illustrates some of the differences between plant cells and other biological systems. Chalmers [19] attributed shear sensitivity in mammalian cultures at least in part to the fact that these cells occur naturally as part of a tissue, surrounded by other cells. The same is true for plant cells. The more robust microbial systems, on the other hand, exist in nature as single organisms or mycelial structures, very close to the forms they assume in submerged culture. 

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