Experimental style

The book was written mainly at the Electrochemistry Laboratory in the University of Pennsylvania, and partly at the Indian Institute of Science in Bangalore. Students in the Electrochemistry Laboratory at the University of Pennsylvania were kind enough to give guidance frequently on how they reacted to the clarity of sections written in various experimental styles and approaches. For the last four years, the evolving versions of sections of the book have been used as a partial basis for undergraduate, and some graduate, lectures in electrochemistry in the Chemistry Department of the University. 

The Frumkin epoch in electrochemistry [i-iii] commemorates the interplay of electrochemical kinetics and equilibrium interfacial phenomena. The most famous findings are the - Frumkin adsorption isotherm (1925) Frumkin s slow discharge theory (1933, see also - Frumkin correction), the rotating ring disk electrode (1959), and various aspects of surface thermodynamics related to the notion of the point of zero charge. His contributions to the theory of polarographic maxima, kinetics of multi-step electrode reactions, and corrosion science are also well-known. An important feature of the Frumkin school was the development of numerous original experimental techniques for certain problems. The Frumkin school also pioneered the experimental style of ultra-pure conditions in electrochemical experiments [i]. A list of publications of Frumkin until 1965 is available in [iv], and later publications are listed in [ii]. 

For the distinction between an experimental style and a taxonomic style of reasoning, see Hacking [1992]. The assumption that the early modem and modem experimental sciences were not taxonomic goes hand in hand with the ignorance of experimental history on experimental history, see above, chapter 2. 

He went on to calculate from the expansion of air a further set of values for the mechanical equivalent of heat which broadly agreed with the electromagnetic experiments. These experiments and, in particular. Joule s concern for very sensitive measuring instruments suggest that he was, to some extent at least, using experiments to prove his theory of the nature of heat. This experimental style contrasts with his earlier, more open-ended approach. 

The purpose of the present chapter is twofold first, to show that the EMR method is a powerful tool for the study of chemical reaction dynamics of large su-pramolecular entities in the same experimental style that was used by physical organic chemists working with small molecules. This will be outlined in 2. Second, I hope to successfully convince the reader that ENDOR and ESEEM spectra can provide sufficiently accurate and reliable information so that derived parameters... 

A weaker but more widely applicable criterion is that the rate constant estimate should be consistent with the body of experimental work on closely related reactions. A third factor is that of style, which is essentially equivalent to the contemporary state of mechanistic chemistry it may seem more reasonable to write a mechanism for one of the forms than for the alternative. Styles change, however. 

Fig. 1 Comparison of the experimentally determined geometries of the hydrogen-bonded complex H3N-- -HC1 and its halogen-bonded analogue H3N- C1F (both drawn to scale) with a non-bonding electron-pair (n-pair) model of NH3. Here, and in other figures, the n-pair electron distribution is drawn in the exaggerated style favoured by chemists. The key to the colour coding of atoms used in this and similar figures is also displayed...

The necessity for a co-catalyst with BF3 was subsequently confirmed rigorously by Evans and Meadows [8-10] by means of an all-glass vacuum apparatus which established a characteristic style of experimentation which I adopted and adapted. They showed that under rigorously anhydrous conditions isobutene and BF3 could be mixed without the isobutene polymerising, and that the addition of water did initiate a polymerisation. Fairbrother and Frith [11] reported very briefly that the polymerisation of isobutene by (Ta-Nb)F5 required a co-catalyst - without stating which one they used. 

The experimental methods are edited versions of original procedures taken from the literature and have been rewritten to provide a uniformity of style. Although care has been taken to ensure that all important and relevant information has been included, consultation of the original literature is recommended, particularly where cautionary notes are included with the experimental details. In several cases, the procedures have been generalised and variations are recorded for the specific examples cited or in the Tables. Wherever possible, limitations of experimental procedures have been given. 

Our research using the CCS approach has focused on the discovery of new dielectric thin films. This example illustrates the power of this approach and key considerations in utilizing high throughput synthesis and screening approaches. A variety of other problems appear well matched to such combinatorial-style methods. A few of these are discussed briefly below, touching on both experimental challenges and research opportunities. 

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