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Mathematic exercise

The name of the program for the mathematical exercise is UCKRON, since it was made in cooperation of Union Carbide Corporation and the University of AKRON (Berty 1989.)... [Pg.120]

For other cases, such as La3+ where more detail is required about the nature of the species present in solution, titration data can be computer fit to more complicated multi-equilibrium models containing Mx 1 v( OR)v forms whose stoichiometry is suggested by information gained from independent spectroscopic or kinetic techniques. One must be mindful of the pitfalls of simply fitting the potentiometric data to complex multi-component models for which there is no independent evidence for the various species. Without some evidence for the species put into the fit, the procedure simply becomes an uncritical mathematical exercise of adding and removing various real and proposed components until the goodness of fit is satisfactory. [Pg.279]

I cannot conclude without referring to the numerous papers dealing with the kinetics of cyclic formal polymerisations. Some of these show considerable mathematical virtuosity in interpreting the kinetic results, but very regrettably they contribute relatively little to our understanding, because the mechanisms used are completely unsubstantiated by any chemical evidence and the nature and concentration of growing centres is unknown. We see here again that kinetics without chemistry is little more than a mathematical exercise. [Pg.736]

We utilize the laboratory, which is not a separate course, in the process of introducing higher level mathematics. For instance, the first day of laboratory is given to mathematics exercises that review simple integrals and derivatives, and the chain rule. This is also where partial derivatives are introduced using the ideal gas law and the van der Waals equation as object lessons. It is here that we also introduce the triangle derivative rule for partial derivatives, Eqn 4. [Pg.287]

In this connection, it is interesting to consider questions of the heat of adsorption on a non-uniform surface, of the fraction of the specific heat of the adsorbed gas related to redistribution of the gas on the surface for a change in temperature, and so on—both for the general case and for a distribution of the form (17). The elaboration of these problems, however, at present would necessarily be nothing more than a mathematical exercise. We note only that for the distribution equation (17), the smaller the value of q, the sharper is the maximum of the specific heat near T = 7, while the differential heat of absorption at T = 0 obeys the equation... [Pg.66]

For our hypothetical example, the best design solution seems to be the straight chair with the fitted massage hood that also plays music. But the Pugh Matrix is not just a simple mathematical exercise it s a qualitative technique that forces discussion and the development of new and alternative options to find the very best one. [Pg.215]

A meta-analysis of studies of the efficacy and toxicity of typhoid fever vaccines (SEDA-23, 343) has been criticized as an interesting mathematical exercise but of httle practical relevance (4). The meta-analysis had lumped together different parenteral whole-ceU vaccines (alcohol-inactivated, formahn-inactivated, acetone-inactivated, and dried whole-ceU vaccines), but the only... [Pg.3539]

To proceed in our model derivation, the equation for internal energy, e, is obtained by subtracting the mechanical energy equation from the total energy equation. The first step in this mathematical exercise, is to formulate the equation for mechanical energy. [Pg.47]

This mathematical exercise was aimed at optimizing a shape of WPC board shown in Figure 7.1. The principal goal was to minimize the cross-sectional area in such a way that the product would by reduced by at least 10% by weight, at the same time retaining (or improving) its mechanical properties exemplified by flexural strength and modulus, and impact resistance. [Pg.312]

The masterlist of individual half-reactions in Table 3 may now be used to derive all possible pairs of two successive, self-consistent half-reactions for each of the three two-construction patterns in Fig, 3. The products of these pairs will in turn constitute substrates for a third successive self-consistent half-reaction to give sequence lists for each of the derived three-construction patterns. In this way general sequence lists for each of the 13 patterns wiU be obtained, containing all possible self-consistent sequences. The generation of these lists is now simply a mechanical mathematical exercise, unprejudiced by chemical preconceptions. Like the masterlist itself they will include sequences of dubious practicality and even presently unknown chemical detail, but they must include all possible sequences derived from the masterlist reactions 2). These lists can also serve to stimulate study of potentially useful construction sequences which are not currently practical. [Pg.72]

Interestingly, when Lineweaver and Burk submitted a paper on the plot, the referees were opposed to its publication in JAMS for a variety of reasons. Some of die reviewers considered the paper "just a mathematical exercise and not really chemistry at all". The method is primarily used nowadays for initial examination of kinetic data and then the data are fitted to an appropriate rate equation using computer programs. [Pg.193]

In using these extrapolation rules, it was clear to the Committee that the establishment ofWQO is not merely a mathematical exercise, but always remains a case-by-case consideration, which calls for expert judgement. [Pg.82]

Other theories, however, do exist, but the majority of these were published well after Flory s. These theories beeame increasingly complex and notwithstanding that they allowed perhaps a somewhat better precision in the determination of Pgei, the equations derived from them are so complex that in practice they are never used. This unnecessary complexity trend has gotten out of hand in certain cases to the level of a purely mathematical exercise rather removed from reality [12-14]. [Pg.192]

A calculation—and it is only a mathematical exercise— shows that if a single matchbook is enclosed in a 2 mil (0.002 in.) thick envelope of the best grade of polyethylene with 100 cm total surface area and exposed to 98% RH, assuming an average interior RH of 55% (1 cm Hg of water vapor pressure differential), the influx of moisture per week would be 28 mg or 0.7% of the weight of the enclosed paper and chemicals. This proves the above-raised point that prolonged, uninterrupted, severe exposure cannot be counteracted by plastic enclosure. [Pg.82]

Consider a simple chair, which is very uncomfortable for sitting, but very convenient for a mathematical exercise. Each of the four legs represents a rod of length a, the seat is simply a square built of identical rods, the bacK consists of three such rods maldng a C shape. The... [Pg.82]

Each letter represents a different digit ranging from zero to nine, and the digits build numbers which in turn build the above-mentioned mathematical exercise. [Pg.243]

The main biographers of Kramers, in particular Dirk ter Haar, claim that his interest in Chemical kinetics is a simple mathematical exercise of style. This may be partially true but Kramers s work would be impossible without Christiansen s previous contribution and his collaboration with Oskar Benjamin Klein (1894-1977) a Swedish theoretical physicist student of Arrhenius that during the years from 1917 to 1921 travelled many times back and forth between Copenhagen and Stockholm to complete his PhD thesis in which he examined the forces between ions in strong electrolyte solutions. The result was a generalized description of liquid dynamics and the formulation of what we call today the Klein-Kramers equation (Klein 1922). [Pg.24]

The solution to the linear integral equations, Eqs. (6.94) and (6.95), are given in detail in various references, which enables an accurate determination of the functions Aj and B/. Since the solution to linear integral equations is a fairly standard mathematical exercise, we instead turn our attention to the specific forms of the property flux expressions and the final closed forms of the conservation equations. [Pg.161]

More than 65 years ago, J. R. Platt [46] suggested the count of paths of different lengths in molecules as a tool for numerical characterization of molecules. The suggestion by Platt is that the sequences of path numbers are the language of interest in comparative study of chemical structures. For some, such a proposition may appear to be a chemically futile mathematical exercise that may entertain some. In the central column of Table 7.1, we show the result of such a mathematical exercise, which offers a numerical representation of octane isomers. For example, 2,3-dimethyhexane... [Pg.200]

After some more mathematical exercises (Karadeniz, 2014 Kee et al., 2005b), the SFR reactor can be described by the following set of equations Mass continuity ... [Pg.60]

A mathematic exercise may help to understand an important part of the underlying principles and may guide the LG chemists to take the right decision let us assume we have a compound collection of 1 million compounds. [Pg.19]

In order to minimize the sum of the squares of the errors, we do the usual mathematical exercise of taking the derivative and setting it equal to zero. For a given set of data, the error, and the sum squared error, will vary as the coefficients change, therefore the derivatives are taken with respect to each coefficient. [Pg.158]

It was when in Washington that Teller worked with Brunauer, a student of his, and assisted in the formulation of what has now become known as the BET equation. To Teller, it appears that this was a mathematical exercise. [Pg.505]

It is easy to say that you have provided a simpler scheme of the elements by looking only at their principal characteristics but, whether the most principal characteristic is the combining form then, like it or not, here we are back at Mendeleev or not, then we will continue to grope among subjective opinions, scholarly prejudices, and mathematical exercises, as chemists have done for half a century with httle to show for it. [Pg.41]

In this section, elementary mechanical models that can describe some aspects of viscoelastic polymeric behavior are presented. Although these simple models cannot represent the behavior of real polymers over their complete history of use, they are very helpful to gain physical understanding of the phenomena of creep, relaxation and other test procedures and to better understand the relationship between stress and strain for a viscoelastic material. Undoubtedly, the first models were developed on the basis of observations and not just as a mathematical exercise. Generalized mechanical models are presented later in Chapter 5. [Pg.84]

A common misconception is that optimization is a complex, esoteric, mathematical exercise. In fact, optimization is usually a (fynamic, creative activity involvii brainstormii exploiii alternatives, and asking, "What if... ... [Pg.441]

At first. Maxwell s relations and the foregoing mathematical exercises may seem somewhat inaccessible. However, as shown in the foUowing examples, the aim of these relations is to rewrite and simplify thermodynamic functions. Before considering the practical apphcation of fundamental equations and Maxwell s relations, however, it is expedient to summarize some of the definitions previously introduced. [Pg.268]


See other pages where Mathematic exercise is mentioned: [Pg.91]    [Pg.287]    [Pg.389]    [Pg.389]    [Pg.617]    [Pg.183]    [Pg.51]    [Pg.14]    [Pg.603]    [Pg.88]    [Pg.77]    [Pg.376]    [Pg.78]    [Pg.75]    [Pg.20]    [Pg.29]    [Pg.15]    [Pg.48]    [Pg.738]    [Pg.72]    [Pg.861]    [Pg.26]   
See also in sourсe #XX -- [ Pg.18 ]




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