Similarity concise summary

The dominant contributor to the reactivity of vinylcyclopropanes in any radical reaction is the form (4a), the cyclopropylcarbinyl radical system. The opening of a cyclopropylcarbinyl radical to a butenyl radical is among the fastest radical processes known, with a rate constant of 1.3 x 10 sec". - The various stereoelectronic effects of this rearrangement have been reviewed. The structure of (4a), deduced from its ESR spectrum - and in agreement with calculations (STO-36 basis set), is in the bisected conformation shown, predicted to be 1.4 kcal mol more stable than its perpendicularly oriented counterpart. Above -KX) T only the butenyl radical (4b) can be detected. Substituent efiects do not seem to operate here when the substituents are on the cyclopropane (i.e. product stabilization). The cy-clopropylcaibinyl cation and anion have structures similar to (4a), bisect conformations (5) and (6), respectively. A concise summary of solvolytic and mechanistic data for system (5) has recently appeai Reviews of cyclopropylcarbinyl anions and carbenes are also available. - ... 

To date, the only experimental examples where a 2° Swain-Schaad relationship resulted in a breakdown of semidassical models and implicated tunneling and coupled motion were from studies of alcohol dehydrogenases (ADH). Furthermore, all these studies were conducted on the oxidation of the alternative substrate benzyl alcohol to aldehyde. The only attempt so far to conduct similar measurements used a very different system (DHFR). These experiments revealed no deviation from the semidassical EXP [45]. Until such experiments are extended to other systems or at least extended to the reduction of aldehyde to alcohol for the same system, the generalization of their interpretation should be taken with some discretion. These examples are discussed in great detail in Chapter 10, Section 10.5.1.1, and only a concise summary of two seminal examples is presented below. 

A report by the International Union of Crystallography Commission on Crystallographic Nomenclature (Lima de Faria et al. 1990) presents a concise description of similar alternative notations, a summary of which is in Table 3.4. 

Fish oils are a byproduct of the production of fish meal. Both commodities are subject to price flucmations that are only indirectly related. The meal has been historically used for terrestrial animal feedsmffs. The production process can be condensed to apply to two basic functions take fish or fish waste, cook it, and squeeze it (Figure 2). Subsequent steps are varied for each commodity, but they essentially are well described by Young (20), whereas the desirable properties of fish meal are concisely described by Bimbo and Crowther (21). Similar summaries, especially on sources and production, are provided by various chapter authors in a book on pelagic fish (22), because most fish caught for meal and oil are pelagic (migratory) and subject to seasonal exploitation. The principal competition to fish meal is soybean meal and other oilseed meals (23). 

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