Selection process compatibility

Transfer The process of moving a liquid, gas, or some forms of solids from a leaking or damaged container to a secure container. Care must be taken to ensure the pump, transfer hoses and fittings, and the container selected are compatible with the hazardous materials. When hazardous substances are transferred, proper concern to electrical continuity (bonding/grounding) must be observed. 

It is also necessary for this selection process to take into account the particular cooling system operational conditions (system volume, retention time, circulating water pH, etc.) and several other factors, such as discharge regulations, compatibility with other chemical treatments, and application costs. 

The choice of sample preparation method is crucial in chemical analysis because it is often the most critical and time-consuming step of an analytical process.35 There is a wide choice of methods for sample pretreatment and preparation for further analysis. Unfortunately, however, there are no universal methods of sample treatment because analytical samples come in a huge variety of forms. Ideally, the sample preparation methodology should be solvent-free, simple, inexpensive, efficient, selective, and compatible with final analytical methods. 

Proper selection of the filter medium is more of an art than a science. The filter cutoff must be chosen to capture the smallest particles of interest. Other factors that must be considered are the type of filter (bulk or surface), the required flow rate, and the size of the membrane. These parameters are not independent and the best choice will usually involve trade-offs. Finally, the material from which the filter is made must be considered. It must be selected for compatibility with the intended postfiltration processing. Glass-fiber filters, for example, often have very high blanks for common ions such as chloride and sodium. 

Criteria considered so far in the selection of a suitable clrng form for MDI development include drug solubility and excipient and component compatibility. In addition to these parameters, suspension properties need to be carefully considered in the selection process. These are discussed in more detail later in this chapter in the section on the development of MDIs. 

Problems such as swab recoverability or interference with adhesive materials are commonly encountered during the swab selection process. It is imperative that the swab selected be compatible with the diluent, the detergents, and the chemical (active/degradant) and it cannot cause interference with the method used for residue analysis, typically FIPLC and/or TOC. A swab recovery study is required for determining the acceptability of a swab. This is performed by spiking the swab with known quantities of the various chemicals under evaluation for potential carryover. The swabs need to be analyzed by the validated method to be used in the cleaning validation studies. An acceptable level of recovery should be no less than 70% and a correction factor needs to be included in final residue calculations. 

The etch rate ratio of the resist to the Si02 reference is referred to as the resist process selectivity, and coupled with resist thermal stability data is representative of the overall resist process compatibility. The lower the selectivity ratio (i.e., 1), the better the resist polymer dry-process compatibility. PMMA, for example, has a marginal selectivity of 0.9-1.2, or etches at the undesirably same rate as Si02. In addition, PMMA is also very susceptible to thermally-induced image flow due to low tg and TGA parameters, and also undergoes surface "frying" phenomena (see Figure 2). Therefore, PMMA has very poor overall dry-process compatibility. 

The use of underfill adhesives has resulted in the development of the draft version of J-STD-030, Guideline for Selection and Application of Underfill Material for Flip Chip and Other Micropackages. The guideline covers critical material properties for underfill materials to assure compatibility in underfill applications for reliable electronic assemblies as well as selected process-related qualification tests such as thermal cycling. Table 6.9 summarizes selected materials requirements for underfill adhesives from the proposed JEDEC J-STD-030. ... 

The selection process is driven by the lubricant s compatibility with the hot resin, lack of adverse effects on polymer properties, good transparency, regulatory approval, and the balance of other additives in the polymer. The amount of lubricant used can also affect the final polymer properties. Overlubrication can cause excessive slippage and underlubrication can cause degradation and higher melt viscosities. 

In a true DCL, equiUbration and selection need to take place simultaneously so the reaction conditions required for reversibihty must also be compatible with the noncovalent interactions employed in the selection process. If basic conditions, for example, are required for exchange to take place, then certain recognition groups may be deprotonated and the building blocks negatively charged under library conditions. The reaction conditions should ideally be mild, so as not to disturb the delicate noncovalent interactions involved in molecular recognition. 

The selection of a conductor material depends on the technical, reliability, and cost requirements of a particular application. Figure 11.7 illustrates the process compatibility of the various types of conductors. 

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