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Outline of the Problem

2 Simple quantitative cost/benefit analysis of higher operating pressures [Pg.103]

Running a fuel ceU at higher pressure will increase the power, but it also involves the expenditure of power, and there is the cost, weight, and space taken up by the compression equipment. To consider the pros and cons of adding the extra apparatus, we have to consider more quantitatively the costs and the benefits of running at higher pressure, which we do in this section. [Pg.103]

What is not shown in this graph is that this voltage boost , AF, is proportional to the logarithm of the pressure rise. This is both an experimental and a theoretical observation. In Section 2.5.4, we saw that the rise in OCV due to the change in Gibbs free energy was given by the equation [Pg.104]

We also saw in equation 3.4 in Chapter 3 that the activation overvoltage is related to the exchange current by a logarithmic function. So, we can say that if the pressure is [Pg.104]

However, this power loss is just the power delivered to the rotor of the compressor. This power comes from an electric motor, which has an efficiency of less than 1, and there are also losses in the connecting shaft and the bearings of the compressor rotor. If we express the combined efficiency of the motor and drive system as r m, then Ihe electrical power used will be greater than the compressor power by a factor of I/rjm, and so there will be a loss of electrical power given by the equation [Pg.106]

for modern chemistry there is no more challenging problem than the creation of an artificial molecular system capable of functioning with an enzymelike efficiency, selectivity, and amenability to control. It is not an exaggeration to claim that the creation of artificial catalysts of that type will be a truly revolutionary breakthrough in chemistry and will lead to in-depth changes in laboratory and industrial syntheses, affecting the whole of civilization. [Pg.395]

Design in this area is following several fairly different pathways. Below we shall discuss just a few approaches closely related to the topic of this chapter. [Pg.395]


In the interests of presenting a general outline of the problems involved in quality control and measurement, the remainder of this discussion is chiefly concerned with an important and representative product—frozen peas. [Pg.30]

Limitations of space forbid more than a sketchy outline of the problems set before the Section of Geophysical-chemistry, but it is hoped that the... [Pg.9]

Touring the past decade homogeneous catalysis has progressed from an interesting novelty to its present status as a recognized field. In the interval a great deal has been said and written concerning the subject, much of it well beyond the scope of this discussion which is limited to an indication of what has been accomplished, an outline of the problems which have been encountered, and a forecast of future prospects. [Pg.204]

It is the purpose of this book to give an outline of the problems underlying the function of organic LEDs utilizing bimolecular charge recombination as a generation process of emitting states. [Pg.473]

Do the main work before starting the search and thus save time during its course. Confer with the originator of the project establish subject, subtopics, and scope of search, amount of time to be spent, and limits of coverage. Insist on a written outline of the problem this will be sometimes even more helpful to the one requesting the search than to the searcher. [Pg.34]

This guide identifies the advantages of competitive voucher schemes in delivering subsidies describes the circumstances under which they are superior to other subsidy mechanisms and explains how to design, implement, monitor, and evaluate a voucher scheme. It provides a broad outline of the problems faced by health systems, the rationale for government intervention, and the different ways in which governments and donors subsidize health care. [Pg.127]

The Navier-Stokes equations are valid whenever the relative changes in p, T and v in the distance of the mean free path are small compared to unity. Inasmuch as the Enskog theory is rather long and involved, we will only provide a brief outline of the problem and the method of attack, and then rather discuss the important results. [Pg.256]

This completes my brief outline of the problems involved in technical translation. It is very incomplete, even as an outline. But the best I could hope to do was to present some of the highlights, and to offer a few practical suggestions. [Pg.528]

The theory of the ri-doubling in the ft state, and the perturbations with the E+state, is quite involved. We give here an outline of the problem, to which we will return in chapter 10. The problem can be represented in the form of a 5 x 5 matrix, constructed... [Pg.556]

For the calculation of the electrostatic term the system under study is characterized by two dielectric constants, in the interior of the cavity the constant will have a value of unity, and in the exterior the value of the dielectric constant of the solvent. From this point the total electrostatic potential is evaluated. Beyond the mere classical outlining of the problem, Quantum Mechanics allows us to examine more deeply the analysis of the solute inserted in the field of reaction of the solvent, making the relevant modifications in the quantum mechanical equations of the system under study with a view to introducing a term due to the solvent reaction field. This permits a widening of the benefits which the use of the continuum methods grant to other facilities provided for a quantical treatment of the system, such as the optimization of the solute geometry the analysis of its wave function, the obtaining of its harmonic frequencies, " etc. all of which in the presence of the solvent. In this way a full analysis of the interaction solute-solvent can be reached at low computational cost. [Pg.23]

The paper is divided into six parts, an abstract, and an appendix with mathematical details. Part 1 gives an introduction and outline of the problem, which shows that the physicist Erich Huckel had a pronounced knowledge about the chemical and physical properties of aromatic compounds. The chemical knowledge was certainly aquired from discussions with his brother Walter Huckel, who was a chemistry professor and textbook author [14]. Huckel discusses benzene, pyridine, pyrrol, furan, thiophene, isomeric forms of dihydrobenzene and chinone, cyclobutadiene, cyclooc-tatetraene, and cyclopentadiene. He points out that there is no satisfactory explanation for the observation why cyclobutadiene does not (at that time) exist, and why benzene and cyclooctatetraene are stable but chemically very different in their reactivity. Huckel emphasizes that the number 6 appears to play a particular role for aromatic compounds, which had been pointed out for the first time by Bamberger in 1890 [15]. [Pg.30]

Modern analysis begins with a definition and outline of the problem and ends only after a detailed critical evaluation of the relevant analytical data is complete, permitting the presentation of a result ( Analytical Chemistry, Purpose and Procedures). The analyst must therefore retain the ability to monitor a sample conscientiously and knowledgably throughout the analytical process. Only the analyst is in a position to assess the quality of a set of results and the validity of subsequent conclusions, although defining the problem and presenting the conclusions is almost always a cooperative multidisciplinary effort. [Pg.78]

Outlines of the Problem of Programmed Morphogenesis. Questions to Be Answered... [Pg.344]


See other pages where Outline of the Problem is mentioned: [Pg.155]    [Pg.156]    [Pg.1024]    [Pg.556]    [Pg.394]    [Pg.1013]    [Pg.162]    [Pg.17]    [Pg.985]    [Pg.432]    [Pg.384]    [Pg.364]    [Pg.85]    [Pg.985]    [Pg.102]    [Pg.314]    [Pg.345]    [Pg.347]    [Pg.349]    [Pg.258]   


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Outline of the Design Problem

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