Qualitative observation

The visible crystals that develop during a crystallization procedure are built up as a result of growth either on nuclei of the material itself or surfaces of foreign material serving the same purpose. Neglecting for the moment the matter of impurities, nucleation theory provides an explanation for certain qualitative observations in the case of solutions. 

If an initially unloaded elastie body is subjeeted to surfaee or body forees, it will be deformed. If the forees are removed, the deformation will disappear, and the body will be returned to the same state it was in before the forees were applied. Certain materials are observed to behave elastieally for limited deformations, but, if those deformations are exeeeded, then the internal strueture of the material may be altered and inelastie deformation may oeeur. The stresses in the body may be different than those that the material would have experieneed if it had responded elastieally, i.e., the stresses may be affeeted by the change in material strueture. When the forees are removed, some residual deformation may remain. These qualitative observations suggest a set of constitutive assumptions whieh will be stated in mathematieal terms below. 

Motivated by the qualitative observations made above, a set of internal state variables deseribing the internal strueture of the material will be intro-dueed ab initio, denoted eolleetively by k. Their physieal meaning or preeise properties need not be established at this point, and they may inelude sealar, veetor, or tensor quantities. The following eonstitutive assumptions are now made ... 

While the constitutive equations formulated in strain space in Section 5.2.1 follow most naturally from the qualitative observations about inelastic behavior made there, the equations are usually cast in terms of stress, rather than strain. Since (5.3) is invertible in e, there exists a function... 

An important implication of the presence of the shear-extension coupling coefficient is that off-axis (non-principal material direction) tensile loadings for composite materials result in shear deformation in addition to the usual axial extension. This subject is investigated further in Section 2.8. At this point, recognize that Equation (2.97) is a quantification of the foregoing implication for tensile tests and of the qualitative observations made in Section 1.2. 

Detailed directions for the preparation of the sodium salt are given by Smith. Sommer also made many qualitative observations on the properties of other salts and of the acid itself and its oxidation product, a disulfide. These observations were put on a firmer base by the extensive investigations of Browne et (see also references 50 and 51). 

The dependence of the transfer constant on the Z substituent, summarized in Figure 9.4, is largely based on studies of the apparent transfer constants of benzyl and cyanoisopropyl RAFT agents in S polymerization 4 409 and qualitative observations of other polymerizations/97... 

Research is proceeding to extend these qualitative observations and provide quantitative links between the mechanical anisotropy and the detailed characterisation of orientation described in this review. 

With growing interest in the chemical behaviour of actinide ions in the environment (1), the complexation of these ions with carbonate anions has been recently attracting particular attention (2-10) due to the ubiquitous presence of carbonate ions in nature (11, 12) and their pronounced tendency to form complexes with heavy metal ions (7, 10-14). In spite of the carbonate complexation of actinides being considered important chemical reactions for understanding the chemistry of actinides in natural fluids, not many experiments have been devoted up to now to the quantitative study of the subject, though numerous qualitative observations are discussed in the literature. Although there are a few papers reporting the formation constants of carbonate complexes... 

Two types of observations show that our model of a gas must be refined. The qualitative observation is that gases can be condensed to liquids when cooled or compressed. This property strongly suggests that, contrary to the assumptions of the kinetic model, gas molecules do attract one another because otherwise they would not cohere (stick together). In addition, liquids are very difficult to compress. This... 

A rate law summarizes the dependence of the rate on concentrations. However, rates also depend on temperature. The qualitative observation is that most reactions go faster as the temperature is raised (Fig. 13.22). An increase of 10°C from room temperature typically doubles the rate of reaction of organic species in solution. That is one reason why we cook foods heating accelerates reactions that lead to the breakdown of cell walls and the decomposition of proteins. We refrigerate foods to slow down the natural chemical reactions that lead to their decomposition. 

The influence of ring size and substitution on the polymerizability of lactones has been reviewed by Hall and Schneider39 about two decades ago. The general qualitative observations are ... 

Solvent effects on the rate of the decarbonylation of MeCOMn(CO)5 were examined by Calderazzo and Cotton (50) and are presented in part in Table IV. In general they are very small, and no regular trends can be discerned. This virtual lack of dependence of the rate on the nature of the solvent and very little correlation between the rate and the dielectric constant of the solvent are typical of substitution reactions of metal carbonyls (J). In the light of the foregoing, a qualitative observation that CpFe(CO)2-COMe decarbonylates much more readily on treatment at reflux in nonpolar heptane or cyclohexane than in polar dioxane is somewhat intriguing 219). 

Chapter 1 which showed that since muscarine mimicked some of the actions of ACh (but not all) while nicotine mimicked the other actions of ACh, then ACh probably acted on two distinct types of receptors. The fact that atropine antagonised the muscarinic effects of ACh but not the nicotinic effects, while tubocurarine blocked the nicotinic effects provided firm evidence for this concept. These simple qualitative observations by Langley and others at the beginning of the twentieth century led to the development of more quantitative pharmacological methods that were subsequently used to identify and classify receptors. These methods were based on the use of both (1) agonist and (2) antagonist drugs ... 

Using the CRC Handbook or another table of densities, find the densities for each of the four woods oak, white pine, balsa, and cedar. Record these ranges. Decide which of the woods your sample might represent. Your answer should be based on both your calculated averaged density and your qualitative observations about the sample. For example, find out if any of the wood types emit a distinct odor or are known as a light-colored or dark-colored wood. 

Before doing any formal analysis, we state a few qualitative features of each type of controller. This is one advantage of classical control. We can make fairly easy physical interpretation of the control algorithm. The analyses that come later will confirm these qualitative observations. 

Now consider the effect of temperature on the rate of reaction. A qualitative observation is that most reactions go faster as the temperature increases. An increase in temperature of 10°C from room temperature typically doubles the rate of reaction for organic species in solution. It is found in practice that if the logarithm of the reaction rate constant is plotted against the inverse of absolute temperature, it tends to follow a straight line. Thus, at the same concentration, but at two different temperatures ... 

Both qualitative observations and quantitative measurements cannot be reproduced with absolute reliability. By reason of inevitable deviations, measured results vary within certain intervals and observations, mostly in form of decision tests, may fail. The reliability of analytical tests depends on the sample or the process to be controlled and the amount of the analyte, as well as on the analytical method applied and on the economical expenditure available. 

Although the fact that the cycloamyloses include a variety of substrates is now universally accepted, the definition of the binding forces remains controversial. Van der Waals-London dispersion forces, hydrogen bonding, and hydrophobic interactions have been frequently proposed to explain the inclusion phenomenon. Although no definitive criteria exist to distinguish among these forces, several qualitative observations can be made. 

An early, qualitative observation of the exceptional reactivity of phenyl and naphthyl acetates having proximate formyl groups was made in 1946 (Vavon and Scandel, 1946). A quantitative study of the alkaline hydrolysis of the 2-, 3- and 4-formylphenyl acetates was made by Holleck et al. (1958). The 2-formyl ester [39] was very rapidly hydrolysed compared with the 3- and... 

The experimental data show that most of the deuterium atoms in the samples examined occupy bond-center sites. The attribution of this site comes both from the observation of a flux peak in the 111 plane (Fig. 11), and of a dip in the (110) axial channel (Fig. 12), together with the channeling simulations shown in Fig. 9 and Fig. 10. Just as in the case of FI-implanted silicon, the qualitative observation of a flux peak in the 111 planar data rules out any possibility of a back-bonded site for the 2H, although some calculations of the B—H structure have suggested this site. The data were analyzed on the assumption that they could be fitted by a combination of a small number of sites of high symmetry. First, the excess hydrogen, i.e., the part of the hydrogen concentration in Fig. 8... 

The kinetics results of the batch reactor runs lead to the following qualitative observations At low CO pressures (less than about 1 atm) the catalysis appears to be first order in ruthenium over the range 0.018 M to 0.072 M and also in Pco as illustrated by the log Pco vs time plots of Fig. 2 and also shown by the method of initial rates. Changes in the sulfuric acid and water concentrations over the respective ranges 0.25 M to 2.0 M and 4 M to 12 M have relatively small effects on the catalysis rates, although the functionalities are complicated and show concave rate vs concentration curves with maximum rates... 

Table 17 presents mutagenic activities in S. typhimurium TA100 at 1 /rmol per plate without S9 for a wide range of mutagens investigated to date. A number of qualitative observations can be made ... 

On the basis of the qualitative observations presented in the preceding section, we have formulated a scheme that explains all of the qualitative aspects. Scheme 9 presents the proposal. It includes the now... 

A summarization of all the data collected at the three Army Ammunition Plants is given in Table 1. The maximum values obtained at each sample location have been listed in this table. Although the results from the different processes are difficult to compare, these qualitative observations can be made. 

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