Process selection influencing factors

The simulation method developed in IMPROVE (cf. Sect. 5.2) is based on correlations between selected influencing factors which have been determined by literature survey and expert discussions in a theoretical rather than empirical way. However, these are just a small excerpt of the success factors relevant for actual design processes. If additional influencing factors are integrated in the simulation for their practical relevance, the models must be validated again. 

Other factors which have a significant influence on process selection iaclude absolute quantity of sulfur present, concentration of various sulfur species, the quantity and concentration of other components ia the stream to be treated, quantity and conditions (temperature and pressure) of the stream to be treated, and, the location-specific environmental regulations governing overall sulfur recovery and allowable sulfur dioxide emissions (3). 

In manufacturing and processing polymer blends, it is thus important that the viscosity ratio be within the optimal range in the actual processing conditions. Not only the polymers to be blended but also the temperature and processing conditions (shear, elongation) should be carefully selected. Other factors, such as interfacial tension [46,47] and elasticity of the blended polymers, may also influence the blend morphology. 

The selection of the equipment for an extraction process is influenced by the factors which are responsible for limiting the extraction rate. Thus, if the diffusion of the solute through... 

The potential influencing factors are selected based on whatever is relevant to the task or process, and will likely include factors such as working conditions, administrative controls, communication, supervision, training, and equipment design, operation, and maintenance. The inclusion of questions such as What Where When and Who may also be help-... 

Complexity in multiphase processes arises predominantly from the coupling of chemical reaction rates to mass transfer rates. Only in special circumstances does the overall reaction rate bear a simple relationship to the limiting chemical reaction rate. Thus, for studies of the chemical reaction mechanism, for which true chemical rates are required allied to known reactant concentrations at the reaction site, the study technique must properly differentiate the mass transfer and chemical reaction components of the overall rate. The coupling can be influenced by several physical factors, and may differently affect the desired process and undesired competing processes. Process selectivities, which are determined by relative chemical reaction rates (see Chapter 2), can thenbe modulated by the physical characteristics of the reaction system. These physical characteristics can be equilibrium related, in particular to reactant and product solubilities or distribution coefficients, or maybe related to the mass transfer properties imposed on the reaction by the flow properties of the system. 

In order to select materials that will maintain acceptable mechanical characteristics and dimensional stability one must be aware of both the normal and extreme thermal operating environments to which a product will be subjected. TS plastics have specific thermal conditions when compared to TPs that have various factors to consider which influence the product s performance and processing capabilities. TPs properties and processes are influenced by their thermal characteristics such as melt temperature (Tm), glass-transition temperature (Tg), dimensional stability, thermal conductivity, specific heat, thermal diffusivity, heat capacity, coefficient of thermal expansion, and decomposition (Td) Table 1.2 also provides some of these data on different plastics. There is a maximum temperature or, to be more precise, a maximum time-to-temperature relationship for all materials preceding loss of performance or decomposition. Data presented for different plastics in Figure 1.5 show 50% retention of mechanical and physical properties obtainable at room temperature, with plastics exposure and testing at elevated temperatures. 

First, CD complexation is selective, moreover highly stereoselective. CD inclusion processes are influenced mainly by hydrophobicity and shape of guest (G) molecule i.e. by the fit of the entire or at least part of complexed molecule to the CD (host) cavity.Thus ste-ric factors are of crucial importance for CD inclusion compounds formation and their stability. For that reason CD inclusion can be considered as a procedure... 

The analyte nature and its appearance (e.g., ionization state) in the mobile phase are also factors that affect the retention mechanism. Eluent pH influences the analyte ionization equilibrium. Eluent type, composition, and presence of counterions affect the analyte solvation. These equilibria are also secondary processes that influence the analyte retention and selectivity and are of primary concern in the development of the separation methods for most pharmaceutical compounds. 

The mechanical and physical properties of moulded parts, particularly those made of thermoplastics, do not depend only on the chemical constitution of the material and its properties. The processing conditions also exercise a considerable influence (Wilkinson Ryan, 1999). Properties such as strength, toughness, hardness may vary to a greater or lesser extent in the same material, or can be selectively varied by choosing a particular processing technique. Those factors that determine the quality... 

These processes are covered in other chapters of this text and will not be described herein. Factors such as substrate size, size distribution, shape, porosity, friability, and solubility may influence the release properties of the coated dosage form. The goal in coating is to apply the film in such a way that its release is governed by the intrinsic properties of the film, and not imperfection (core penetration, surface pores and defects, fines imbedded in the film, non-uniformity of distribution, etc.). In addition to the properties of the substrate and the coating material, the type of process selected may have a significant impact on the behavior of the finished product. 

The activity of a fungicide and its selectivity under real-life conditions in a complex system of the fungal pathogen, the plant, the environment, and time is determined by a multitude of quite different influencing factors [58]. In the optimization process of a lead structure it is useful to separate such influencing factors... 

Chapter 7 elaborates various important influencing factors of EMM. Influence of lEG, temperature, concentration, electrolyte flow, and tool feed rate has also been described with the help of large number of practical results. Chapter 8 concentrates on various strategies to improve machining accuracy of EMM. Hybrid EMM teclmiques which are the newer developments to improve the effectiveness of EMM have also been included. Selections of optimal combination of EMM parameters validated by test results have also been incorporated to enhance the machining efficiency and accuracy. Chapter 9 includes numerous practical and industrial applications of EMM. Various factors which restrict the wider usability of this process have been discussed. This Chapter also focuses on how to minimize these adverse factors by applying various remedial measures. 

To understand the real system in terms of the properties to be modeled. Thus, one needs to have some background understanding of the modeled objects or processes. Their main features and their interrelation are evaluated. First, it consists of the selection of the influencing factors (input variables) and the outcome (output variables). Then, a mathematical model is constructed at an appropriate level. For example, atoms and molecules can be modeled... 

Szajnar, J. (2009). The influence of selected physical factors on the crystallization process and casting structure, Archives of Foundry Engineering, ISBN 1897-3310, Katowice-Gliwice,... 

From Fig. 11/2.2-1 it is seen that a team with a team leader is necessary to select the process. However, in certain cases team formation may not be mandatory. Also it is necessary that the team leader or who is leading from the front must have expertise (may he acquired through experience). There are a number of influencing factors that are responsible in the selection process. In addition, stage of the project, available... 

There are a few influencing factors that ditectly affect the PHA selection process, as shown in Fig. II/2.2.3-1. 

Pinto JF, Buckton G, Newton JM. The influence of four selected processing and formulation factors on the production of spheres by extrusion and spheronization. Int J Pharm 1992 83 187-196. 

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