The Design Procedure

The possibilities and limitations of the design of bioactive compounds will now be discussed against the background of the three main phases of action. Various relevant aspects of the modulation of the pharmacodynamics and pharmacokinetics are considered. 

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The thermal design of cooling towers follows the same general procedures already presented. Integration of equation 35 is usually done numerically using the appropriate software, mass-transfer coefficients, saturation enthalpies, etc. In mechanical-draft towers the air and water dows are both suppHed by machines, and hence dow rates are fixed. Under these conditions the design procedure is straightforward. 

It should be notea that the design procedures discussed in this section are not apphcable to reboiled absorbers, which should be designed according to the methods described in Sec. 13. 

Process Safety System (PSS) A process safety system comprises the design, procedures, and hardware intended to operate and maintain the process safely. 

They started from the sequence of a domain, Bl, from an IgG-binding protein called Protein G. This domain of 56 amino acid residues folds into a four-stranded p sheet and one a helix (Figure 17.16). Their aim was to convert this structure into an all a-helical structure similar to that of Rop (see Chapter 3). Each subunit of Rop is 63 amino acids long and folds into two a helices connected by a short loop. The last seven residues are unstructured and were not considered in the design procedure. Two subunits of Rop form a four-helix bundle (Figure 17.16). 

The design procedure described above will, in theory, be applicable only to samples that are separated by isocratic development. Under gradient elution conditions the (k ) value of each solute is continually changing, together with the viscosity of the... 

Having converted the VOC-recovery problem into a heat-transfer task we now proceed to develop the design procedure. 

The design procedure starts by identifying the minimum utility cost for a given heat-transfer driving force. Next, the fixed and operating costs are traded off by iterating over the driving forces until the minimum total annualized cost TAC is attained. 

The first and most important aim of design methodology is to produce, by systematic analysis, a description of the design procedure that is commonly accepted and used in every process in different markets. The idea is to make a description of the technical process of design in other words, to answer two questions ... 

What is to be made clear and done during the design procedure ... 

At this step in the design procedure, it is necessary to consider the type of contaminant emission that the booth is designed to control. With the above assumption of influx velocity (0.1 to 0.2 m s ), all emitted material should remain in the booth. With these velocities, it will not be possible to draw in any contaminants that escape the booth. In case of doubt, the influx velocity, zv , should be increased and the necessary hood flow rate should be recalculated. 

The collection efficiency of wet scrubbers is dependent on parameters such as the size and quantity of liquid droplets, the liquid/gas ratio, high wa-ter-to-particle relative velocity, wettability of dust, particle density, gas viscosity, etc. For any specific application, the design procedure is to review operating data available from the technical literature or from manufacturers for similar applications. If data are not available, it may be necessary to per form pilot scale tests, which can be used for scale-up purposes. 

If these two assumptions are incorrect, the solution given here will be incorrect. This will show up in the design procedure, Step 5, Check actual value of P. If the calculated value of Pj is more than 1.25 times the assumed value of P dimensions should be adjusted to bring the calculated and assumed values into line. If the calculated value of P cannot be brought into line by reasonable dimensional adjustment, refer to the NACA Technical Note 2893. 

An example is offered on the following pages of the design procedure to be followed in designing a combination casing string. 

The site layout needs to be presented to management, union, staff and possibly others to obtain approval, and the design procedure described here, together with visualization, will assist the presentation. 

The design procedure will vary with the type of flue, but the basic procedure will not change. It is necessary to consider the relevant parameters discussed above and decide on flue dimensions and materials of construction to satisfy them. The parameters to consider are ... 

The next step in the design procedure is to select the materials. The considerations are the physical properties, tensile and compressive strength, impact properties, temperature resistance, differential expansion environmental resistance, stiffness, and the dynamic properties. In this example, the only factor of major concern is the long-term stiffness since this is a statically loaded product with minimum heat and environmental exposure. While some degree of impact strength is desirable to take occasional abuse, it is not really subjected to any significant impacts. 

Using several materials such as PP, glass-filled PS, and PS molded structural foam that is a natural sandwich panel material, the design procedure follows to determine the deflection and stress limitations of the material in each of the several designs. 

The design procedure for horizontal separators is illustrated in the following example, example 10.6. 

Only a brief review of the fundamental principles that underlie the design procedures will be given a fuller discussion can be found in Volume 2, and in other text books King (1980), Hengstebeck (1976), Kister (1992). 

The design procedures for columns employing steam distillation is essentially the same as that for conventional columns, making allowance for the presence of steam in the vapour see Volume 2, Chapter 11. 

The principal use of this method is in the rating of an existing exchanger. It can be used to determine the performance of the exchanger when the heat transfer area and construction details are known. The method has an advantage over the use of the design procedure outlined above, as an unknown stream outlet temperature can be determined directly, without the need for iterative calculations. It makes use of plots of the exchanger effectiveness versus NTU. The effectiveness is the ratio of the actual rate of heat transfer, to the maximum possible rate. 

The design procedure is similar to that for shell and tube exchangers. 

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