Explicative studies

MMA polymerization is one of the most studied systems and was thought to be explicable, within experimental error, in terms of Bemoullian statistics. Moad et ai.jb have made precise measurements of the configurational sequence distribution for PMMA prepared from 13C-labeled monomer. It is clear that... 

Hersey and Robinson also foundthat many guest species that show kinetic behavior apparently explicable in terms of a single-step binding, give a discrepancy between the values of the equilibrium constant determined kinetically and those determined from equilibrium studies. It was found that the equilibrium constant, deterrmned spectrophotometrically, was usually greater than the ratio of the forward and backward rate-constants, determined kinetically. They therefore suggested that this discrepancy could be adequately explained if the two-step mechanism just described was used to interpret the results. A similar proposal has also been made by Hall and coworkers, who observed a large discrepancy between AV° values for the inclusion of 1-butanol and 1-pentanol by alpha cyclodextrin, calculated from equilibrium-density measurements and kinetic, ultrasonic-absorption data. 

All the numerous other polar cycloaddition reactions studied show a regiospecificity explicable only on polar grounds and thus warrant examination of how acrylonitrile (127) and methyl methacrylate (128)... 

Penetration into insects is greatly influenced by the manner in which the compound is presented. Classic studies by Treherne (19) indicated that when the toxicant is supplied to detached insect cuticle in aqueous solution penetration decreased with increasing polarity, explicable on the assumption that partition into and passage through the lipoidal epicuticle is the rate determining step. In contrast several studies (20 - 22) have shown that when the toxicant is dissolved... 

Although perhaps explicable, or at least precedented, in terms of the greater resonance energy of esters than corresponding amides, nonetheless, a further study is welcomed as this is the only thermochemical information we have on this class of compounds. 

While this question of a possible minority species in this surface reaction remains unresolved, one important aspect of the more complete PhD study is the determination of the chemisorption Ti— bondlengths to both the carboxylate (2.08 0.03 A) and hydroxyl (2.02 0.05 A) species, which turn out to be in excellent agreement with the values (2.08 and 2.01 A, respectively) for the one theoretical (DFT) calculation that considers this coadsorption situation explic-... 

Marcus theory (15) has been applied to the study of the reductions of the jU,2-superoxo complexes [Co2(NH3)8(/u.2-02)(/i2-NH2)]4+ and [Co2(NH3)10(ju.2-O2)]6+ with the well-characterized outer-sphere reagents [Co(bipy)3]2+, [Co(phen)3]2+, and [Co(terpy)2]2+, where bipy = 2,2 -bipyridine, phen = 1,10-phenanthroline, and terpy = 2,2 6, 2"-terpyridine (16a). The kinetics of these reactions could be adequately described using a simple outer-sphere pathway, as predicted by Marcus theory. However, the differences in reactivity between the mono-bridged and di-bridged systems do not appear to be explicable in purely structural terms. Rather, the reactivity differences appear to be caused by charge-dependent effects during the formation of the precursor complex. Some of the values for reduction potentials reported earlier for these species (16a) have been revised and corrected by later work (16b). 

The active development of computational methods aimed at molecular design [1.38-1.41] provides a means for building up a theoretical supramolecular chemistry of not only explicative but also predictive power. Significant insight has already been gained and much more may be expected from the interplay of theory and experiment in the study of supramolecular features (interactions, structures, dynamics, association constants, medium effects, etc.) [1.35, 1.42-1.50, A.37]. 

Many of you have expressed an interest in a format for your master schedule. Figure 1 depicts the format Mobay Chemical Corp. uses. It is self explanatory and covers the items required in the GLP regulations (test substance test system nature of study study initiation date current status sponsor identity, if explicable and name of study director). For a contract laboratory, the sponsor s identity must appear on the master schedule sheet for each study listed. There are several terms that require definition. In... 

Regarding the spatial aspects of the enzymatic degradation of CA-g-PLLA, a surface characterization [30] was carried out for melt-molded films by atomic force microscopy (AFM) and attenuated total-reflection Fourier-transform infrared spectroscopy (ATR-FTIR) before and after the hydrolysis test with proteinase K. As exemplified in Fig. 3 for a copolymer of MS = 22, the AFM study showed that hydrolysis for a few weeks caused a transformation of the original smooth surface of the test specimen (Fig. 3a) into a more undulated surface with a number of protuberances of 50-300 nm in height and less than a few micrometers in width (Fig. 3b). The ATR-FTIR measurements proved a selective release of lactyl units in the surface region of the hydrolyzed films, and the absorption intensity data monitored as a function of time was explicable in accordance with the AFM result. 

This study was conducted to meet three aims to empirically assess and further develop the conceptual ideas of the travel career pattern approach, to further explicate the concept of travel career and establish methods for its measurement and finally, to investigate the cross-cultural applicability of a travel career pattern conceptual scheme through the use of a Korean sample. 

The approach taken here to understand and explicate the purposes of tourism research is an interpretive one and is an attempt to provide a purposeful structure to locate and inform the future study of tourist behaviour. To restate the style being adopted, this analysis of the goals of tourism research is qualitative rather than quantitative it is an approach that begins with the author s personal immersion in the activity. 

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