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Basic Questions

The designer of an evaporator system must have a fundamental knowledge of the properties and applications of common materials of construction and of the corrosive effects of common chemicals. He must also be familiar with the basic standards and practices for using materials of construction. This basic knowledge should enable the designer to  [Pg.336]

Materials of construction can be determined only by understanding the equipment required for the process conditions. Several properties of process fluids are important for proper selection of materials of construction  [Pg.337]

Several questions should be addressed when considering materiels of construction for a particular application  [Pg.337]

Selection of materials of construction must be made only after considering safety and economics of the process as well as its workability. Factors that must be considered include  [Pg.338]


Experimental measurements of dipole moments give size but not direction We normally deduce the overall direction by examining the directions of individual bond dipoles With alkenes the basic question concerns the alkyl groups attached to C=C Does an alkyl group donate electrons to or withdraw electrons from a double bond d This question can be approached by comparing the effect of an alkyl group methyl for exam pie with other substituents... [Pg.196]

Modem real time instmmental methods permit analyses of unstable transient species and the free-radical intermediates as well. These methods have gready expanded the scope and power of VPO studies, but important basic questions remain unresolved. Another complication is the role of surface. Peroxide decompositions and radical termination reactions can occur on a surface so that, depending on circumstances, surfaces can have either an inhibiting or accelerating effect. Each surface has varying amounts of adventitious contaminants and also accumulates deposits during reaction. Thus no two surfaces are exactly alike and each changes with time. [Pg.338]

At this point, attention can be given to specific electrophilic substitution reactions. The kinds of data that have been especially useful for determining mechanistic details include linear ffee-energy relationships, kinetic studies, isotope effects, and selectivity patterns. In general, the basic questions that need to be asked about each mechanism are (1) What is the active electrophile (2) Which step in the general mechanism for electrophilic aromatic substitution is rate-determining (3) What are the orientation and selectivity patterns ... [Pg.571]

Figure 1-1 Basic Questions of Composite Materials and Structures... Figure 1-1 Basic Questions of Composite Materials and Structures...
The basic questions of The What, The Why, and The How of composite materials and structures have been addressed. Much more could be said about, for example, polymers, metals, ceramics, and carbon used as matrix materials. Also, many more composites manufacturing techniques are available. Moreover, many more examples of effective use of composite materials in structures do exist. However, an introduction to each topic has been provided, and hopefully, those introductions will suffice for the purpose of giving background on composite materials prior to studying their mechanics. [Pg.52]

However, as mentioned previously, orthotropic laminae are often constructed in such a manner that the principal material coordinates do not coincide with the natural coordinates of the body. This statement is not to be interpreted as meaning that the material itself is no longer orthotropic instead, we are just looking at an orthotropic material in an unnatural manner, i.e., in a coordinate system that is oriented at some angle to the principal material coordinate system. Then, the basic question is given the stress-strain relations In the principal material coordinates, what are the stress-strain relations in x-y coordinates ... [Pg.76]

Figure 5-1 Basic Questions of Laminated Plate Analysis... Figure 5-1 Basic Questions of Laminated Plate Analysis...
The objective of this chapter is to address introductory sketches of some fundamental behavior issues that affect the performance of composite materials and structures. The basic questions are, given the mechanics of the problem (primarily the state of stress) and the materials basis of the problem (essentially the state of the material) (1) what are the stiffnesses, (2) what are the strengths, and (3) what is the life of the composite material or structure as influenced by the behavioral or environmental issues in Figure 6-1 ... [Pg.331]

You are to address several questions. Basic questions such as given the parameters, which of those four materials leads to the most cost-effective design Which leads to the least-weight solution for this... [Pg.398]

The method of optimization is a brute-force search technique. All the possible laminates that can be obtained by changing the individual laminae orientations by 5° increments are candidates for the optimization process. We consider RC7 because this program is widely used and because it is representative of the brute-force search technique. The basic question is because we must carry a certain load, what laminate do we need We have no idea how many layers are required, much less their orientation, but we must start someplace. [Pg.435]

A number of examples have been studied in recent years, including liquid sulfur [1-3,8] and selenium [4], poly(o -methylstyrene) [5-7], polymer-like micelles [9,11], and protein filaments [12]. Besides their importance for applications, EP pose a number of basic questions concerning phase transformations, conformational and relaxational properties, dynamics, etc. which distinguish them from conventional dead polymers in which the reaction of polymerization has been terminated. EP motivate intensive research activity in this field at present. [Pg.510]

There are two basic questions which can be decided only by experiments. First, we must know whether the metal or the oxygen is present in excess, and second, we must know how the excess component is incorporated in the oxide lattice. In connection with the latter question we have to remember that a non-stoichiometric crystal remains electrically neutral (except in narrow regions near the surfaces), so that if the excess component is present in the crystal as ions, lattice defects with charges of opposite sign must necessarily be present also (see Figs. 1.77 and 1.78). The most important defect structures will be discussed in this section. [Pg.245]

EINSTein (Enhanced ISAAC Neural Simulation Toolkit), was developed to address the basic question To what extent is land combat a self-organized complex... [Pg.593]

Interpreting CA in this much broader light, this chapter addresses the following basic question What general insights does the study of cellular automata give -both on the micro- or macro-scale into the way our universe works T Unless otherwise stated, whenever we use the phrase CA-like in this chapter, we mean any formalism that adheres to the three (or four) basic properties of cellular automata listed above. [Pg.607]

Such an experience with one plastic, PVC, makes it doubly important to carefully examine any plastic to be used with a food product. The basic question to be answered is Does the plastic container provide adequate protection to the food product during the entire life cycle of the container Adequate protection of a food product in a polyethylene container implies that there is no undesirable change in the chemical content of the food during storage in the container. Thus, our study is concerned with the ways in which food products can change when stored in polyethylene containers. [Pg.57]

It is common that mechanochemical degradation involves scission of the macromolecule, so one basic question would be to inquire about the level of stress necessary to separate two chemical moieties which have been attached by a covalent bond. Besides the academic interest, the breaking strength of a covalent bond is associated with the ultimate properties of engineering materials and has attracted considerable attention since the beginnings of quantum chemistry. [Pg.106]

Appendix B answers the basic question What materials and instruments are needed to start electrochemical promotion experiments ... [Pg.11]


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