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Interpretation remarks

The activation energy varies with the temperature during the reaction, indicating that there was a change of mechanism or compensatory effect. [Pg.48]


Interpretation, Remarks and Relation with Other Techniques... [Pg.131]

The phrases in table 6.3 are often followed by the personal pronoun we (e.g., In the present study, we...). In such instances, we is used to signal the beginning of the authors presented work in the journal article. (Recall that we is also used in Results sections to signal human choice and in Discussion sections to signal interpretative remarks.) Table 6.4 lists some verbs that typically follow we in the fill-the-gap statement. Note that the verbs are in present tense when they refer to what is presented in the paper (e.g., we present ) they are in past tense when they refer to work done in the past (e.g., we measured ). (See table 6.5 for a summary of common functions of verb tense—voice combinations in Introductions.)... [Pg.223]

Move 1 (Interpret or Explain Results) is often integrated into the poster Results section, thereby becoming a combined Results and Discussion (R D) section. An example of a combined R D section is shown in hgure 9.1. In such posters, interpretative remarks (Discussion) are included right along with the graphics (Results). In this way, space is conserved, and viewers can read and interpret the data simultaneously (usually easier than looking back and forth between the two sections). For instructional purposes, however, we have placed move 1 in the Discussion section, and we use a stand-alone Discussion section in the three hypothetical posters presented below. We follow this approach, in part, to maintain a clear distinction between results (just the facts) and discussion (interpretation of the facts). [Pg.322]

Nevertheless, a few interpretative remarks are encouraged viewers want to know what you think about your data. [Pg.323]

Hedging Hedging words should be used to soften interpretive remarks in posters. A few examples are presented below hedging words are italicized ... [Pg.325]

Recently Desimoni et used the same bis(oxazoline) ligand in the magnesium(II) catalysed Diels-Alder reaction of the N-acyloxazolidinone depicted in Scheme 3.4. In dichloromethane a modest preference was observed for the formation of the S-enantiomer. Interestingly, upon addition of two equivalents of water, the R-enantiomer was obtained in excess. This remarkable observation was interpreted in terms of a change from tetrahedral to octahedral coordination upon the introduction of the strongly coordinating water molecules. [Pg.81]

To obtain the monolayer capacity from the isotherm, it is necessary to interpret the (Type II) isotherm in quantitative terms. A number of theories have been advanced for this purpose from time to time, none with complete success. The best known of them, and perhaps the most useful in relation to surface area determination, is that of Brunauer, Emmett and Teller. Though based on a model which is admittedly over-simplified and open to criticism on a number of grounds, the theory leads to an expression—the BET equation —which, when applied with discrimination, has proved remarkably successful in evaluating the specific surface from a Type II isotherm. [Pg.42]

In this case the crack is said to have a zeroth opening. The cracks of a zeroth opening prove to possess a remarkable property which is the main result of the present section. Namely, the solution % is infinitely differentiable in a vicinity of T, dT provided that / is infinitely differentiable. This statement is interpreted as a removable singularity property. In what follows this assertion is proved. Let x G T dT and w > (f in O(x ), where O(x ) is a neighbourhood of x. For convenience, the boundary of the domain O(x ) ia assumed to be smooth. [Pg.114]

When Max Planck wrote his remarkable paper of 1901, and introduced what Stehle (1994) calls his time bomb of an equation, e = / v , it took a number of years before anyone seriously paid attention to the revolutionary concept of the quantisation of energy the response was as sluggish as that, a few years later, whieh greeted X-ray diffraction from crystals. It was not until Einstein, in 1905, used Planck s concepts to interpret the photoelectric effect (the work for which Einstein was actually awarded his Nobel Prize) that physicists began to sit up and take notice. Niels Bohr s thesis of 1911 which introduced the concept of the quantisation of electronic energy levels in the free atom, though in a purely empirical manner, did not consider the behaviour of atoms assembled in solids. [Pg.131]

Most manufacturers do not specify the asymmetry factor. Therefore this parameter can serve only for the observation of the column performance during its use. For interpretation, see the remarks about discarding a column. [Pg.435]

This discussion of sources of curvature in Br insted-type plots should suggest caution in the interpretation of observed curvature. There is a related matter, concerning particularly item 5 in this list, namely, the effect of a change in transition state structure. Br nsted-type plots are sometimes linear over quite remarkable ranges, of the order 10 pK units, and this linearity has evoked interest because it seems to be incompatible with Marcus theory, which we reviewed in Section 5.3. The Marcus equation (Eq. 5-69) for the plot of log k against log K of the same reaction series requires curvature, the slope of the plot being the coefficient a. given by Eq. (5-67). A Brjinsted plot, however, is not a Marcus plot, because it correlates rates and equilibria of different reactions. The slope p of a Br nsted plot is defined p = d log kobs/d pK, which we can expand as... [Pg.354]

The interpretation of these remarkable properties has excited considerable interest whilst there is still some uncertainty as to detail, it is now generally agreed that in dilute solution the alkali metals ionize to give a cation M+ and a quasi-free electron which is distributed over a cavity in the solvent of radius 300-340 pm formed by displacement of 2-3 NH3 molecules. This species has a broad absorption band extending into the infrared with a maximum at 1500nm and it is the short wavelength tail of this band which gives rise to the deep-blue colour of the solutions. The cavity model also interprets the fact that dissolution occurs with considerable expansion of volume so that the solutions have densities that are appreciably lower than that of liquid ammonia itself. The variation of properties with concentration can best be explained in terms of three equilibria between five solute species M, M2, M+, M and e ... [Pg.77]

In general, the analysis of essential oils merely involves the application of the ordinary principles of analytical chemistry to this special group of bodies, which possess many features in common. Of course, many special processes have to be used in certain cases, to which attention will be drawn where necessary. The present chapter will be devoted to the details of a few methods which are in very common use in the analysis of these bodies, and which are absolutely necessary in order to form an opinion on the purity of very many oils. Particular processes are mentioned as required under the essential oils or compounds concerned. These remarks may be prefaced by saying that the obtaining of the results of an analysis of an essential oil is not always as difficult a matter as the interpretation of the same when obtained. [Pg.299]

If, in the same way, we use (72) to define for the other processes the characteristic units J, L, and Y, similar remarks can be made with regard to J and J, with regard to L and L, and likewise with regard to Y and Y. By equation (72) a precise definition has been given to the characteristic unit of any process and we must hope that in the future the study of ionic solutions will eventually provide a complete interpretation of these quantities. At the present time we are very far from this goal. At any rate the total unitary quantity for each process must be isolated and evaluated before it can be interpreted. In the remaining chapters of this book we shall have occasion to mention only the quantities D, L, Y, J, and U, defined in accordance with (72) and (73). If, however, anyone should wish to give a precise definition to a quantity that includes less than the whole of the unitary term, the symbols in bold-faced type remain available for this purpose. [Pg.101]

Returning to the observed values for these cesium salts, plotted as dark circles in Fig. 57, we must conclude that the position of the experimental points—nearer the diagonal than any salt of Rb, K, or Na—does not indicate anything unusual about the aqueous solution of the cesium salts, but merely arises from the fact that these cesium salts happen to crystallize in a more compact lattice structure, with less void space between the ions. We cannot make a similar remark about the points for the lithium salts, which lie astride the diagonal the interpretation of these values will be discussed later. [Pg.190]

The examination of this idea has subsequently formed an integral part of my research in the philosophy of chemistry. This has also led to a certain amount of disagreement with other authors who appear to interpret Lowdin s remark in a somewhat different manner (Ostrovsky, 2001). I now deeply regret not having contacted Lowdin directly in order to seek his own clarification. In the present contribution I intend to revisit this question and to take the opportunity to respond to some critics as well as hopefully injecting some new ideas into the discussion. [Pg.92]

Despite the remarkable progress made, however, the trend shown in the table reveals a fact that cannot be interpreted favorably, at least to this author. In the third quarter of the 20th century, the structures of five different kinds of new luciferins have been determined, whereas, in the last quarter, only three structures, of which two are nearly identical, have been determined. None has been determined in the last decade of the century and thereafter, thus clearly indicating a declining trend, in contradiction to the steady advances in analytical techniques. The greatest cause for the decline seems to be the shift of research interest from chemistry and biochemistry into genetic biotechnology in the past 20 years. [Pg.492]

On the other hand, Davies5 , studying the reaction of adipic add with 1,5-pentanediol in diphenyl oxide or diethylaniline found an order increasing slowly from two with conversion. From this result he concluded that Flory s1,252-254> and Hinshelwood s240,241 interpretations are erroneous. Two remarks must be made about the works of Davies5 experimental errors relative to titrations are rather high and kinetic laws are established for conversions below 50%. Under such conditions the accuracy of experimental determinations of orders is rather poor. [Pg.77]

To conclude this section we make a few remarks concerning the physical interpretation of the covariant amplitude tfr(x). For a free particle one would surmise that adoption of the manifold of positive... [Pg.535]

There have been remarkably few reviews of the chemistry of decompositions and interactions of solids. The present account is specifically concerned with the kinetic characteristics described in the literature for the reactions of many and diverse compounds. Coverage necessarily includes references to a variety of relevant and closely related topics, such as the background theory of the subject, proposed mechanistic interpretations of observations, experimental methods with their shortcomings and errors, etc. In a survey of acceptable length, however, it is clearly impossible to explore in depth all features of all reports concerned with the reactivity and reactions of all solids. We believe that there is a need for separate and more detailed reviews of topics referred to here briefly. The value of individual publications in the field, which continue to appear in a not inconsiderable flow, would undoubtedly be enhanced by their discussion in the widest context. Systematic presentation and constructive comparisons of observations and reports, which are at present widely dispersed, would be expected to produce significant correlations and conclusions. Useful advances in the subject are just as likely to emerge in the form of generalizations discerned in the wealth of published material as from further individual studies of specific systems. Perhaps potential reviewers have been deterred by the combination of the formidable volume and the extensive dispersal of the information now available. [Pg.283]

Intramolecular Isotope Effects. The data in Figure 2 clearly illustrate the failure of the experimental results in following the predicted velocity dependence of the Langevin cross-section. The remark has been frequently made that in the reactions of complex ions with molecules, hydrocarbon systems etc., experimental cross-sections correlate better with an E l than E 112 dependence on reactant ion kinetic energy (14, 24). This energy dependence of reaction presents a fundamental problem with respect to the nature of the ion-molecule interaction potential. So far no theory has been proposed which quantitatively predicts the E l dependence, and under these circumstances interpreting the experiment in these terms is questionable. [Pg.101]


See other pages where Interpretation remarks is mentioned: [Pg.175]    [Pg.174]    [Pg.48]    [Pg.175]    [Pg.174]    [Pg.48]    [Pg.95]    [Pg.51]    [Pg.568]    [Pg.61]    [Pg.82]    [Pg.41]    [Pg.235]    [Pg.261]    [Pg.84]    [Pg.466]    [Pg.515]    [Pg.64]    [Pg.207]    [Pg.104]    [Pg.190]    [Pg.660]    [Pg.922]    [Pg.45]    [Pg.628]    [Pg.577]    [Pg.202]    [Pg.136]    [Pg.88]    [Pg.746]    [Pg.66]   


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Interpretation, Remarks and Relation with Other Techniques

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