"Wow. What a book and what an undertaking. This should be a must-read for the most exacting fly fisherman. I would guess that it will be one of the most important reference volumes ever written. It should be read and re-read many times."--Ed Shenk, author of Ed Shenk's Fly Rod Trouting • Strategies for fooling tough fish in all types of environs, from tailwaters to spring creeks to Gaspe salmon streams • Breathtaking photos from the top streams around the world • Hundreds of innovative fly patterns with recipes and notes
"Wow. What a book and what an undertaking. This should be a must-read for the most exacting fly fisherman. I would guess that it will be one of the most important reference volumes ever written. It should be read and re-read many times."--Ed Shenk, author of Ed Shenk's Fly Rod Trouting • Strategies for fooling tough fish in all types of environs, from tailwaters to spring creeks to Gaspe salmon streams • Breathtaking color photos from the top streams around the world • Hundreds of innovative fly patterns with recipes and notes
The aim of this Workshop on "Selectivity in Chemical Reactions" was to examine the specific preferences exhibited by simple chemical reactions with regards to reagents having particular energy states, symmetries, alignment and orientation and the resulting formation of certain products with their corresponding energies, states, alignment and polarisation. Such problems come close to the ultimate goal of reaction dynamics of being able to determine experimentally and theoretically state-to-state cross sections and stereochemical effects under well defined and characterised conditions. There are many examples of highly selective and specific processes to be found in atmospheric and combustion chemistry and the production of population inversions amongst vibrational and electronic states lies at the heart of the development of chemical laser systems. Only when we can understand the fundamental processes that underlie the selectivity in the formation of products in a chemical reaction and the specific requirements of initial states of the reagents, can we expect to be able to develop the explanatory and predictive tools necessary to apply the subject to the development of new laser systems, efficient combustion schemes and specific methods of chemical synthesis, to the control of atmospheric pollution and to all problems in which it is necessary to direct the outcome of a chemical reaction in a specific way. The brief given to the Workshop was to critically review the field, to discuss the present limitations and difficulties and to identify new directions.
Selectivity is an increasingly important part of organic synthesis. The whole basis of organic chemistry, and especially organic synthesis, depends upon the selectivity which can be achieved in organic reactions. This concise textbook describes the strategies which can be adopted to improve selectivity, and the reactions which have been specially designed to afford high selectivity. The aim is to illustrate the range of processes to which these principles can be applied and the high degree of selectivity which can be achieved. Selectivity in Organic Synthesis aims to provide a solid introduction to this subject, focusing on the key areas and applications.
This book brings together a number of studies which examine the ways in which the retention and selectivity of separations in high-performance liquid chromatography are dependent on the chemical structure of the analytes and the properties of the stationary and mobile phases. Although previous authors have described the optimisation of separations by alteration of the mobile phase, little emphasis has previously been reported of the influence of the structure and properties of the analyte.The initial chapters describe methods based on retention index group increments and log P increments for the prediction of the retention of analytes and the ways in which these factors are influenced by mobile phases and intramolecular interactions. The values of a wide range of group increments in different eluents are tabulated.Different scales of retention indices in liquid chromatography are described for the comparison of separations, the identification of analytes and the comparison of stationary phases. Applications of these methods in the pharmaceutical, toxicology, forensic, metabolism, environmental, food and other fields are reviewed. The effects of different mobile phases on the selectivity of the retention indices are reported. A compilation of sources of reported retention index values are given.Methods for the comparison of stationary phases based on the interactions of different analytes are covered, including lipophilic and polar indices, shape selectivity comparisons, their application to novel stationary phases, and chemometric methods for column comparisons.
The demand for selective organic reactions is growing more acute everyday. Indeed, greater product selectivity has an important impact on energy and resource utilization, in terms of reduced process energy requirements for product separation and purification, in terms of low-value by-products, and in terms of environmental acceptance and compatibility. Moreover, more and more chemicals, especially pharmaceuticals, have to be sold in an optically active form. The search for selectivity constitutes a tremendous challenge for the chemists. In the last two decades, homogeneous transition metal based catalysis has emerged as one of the most promising tools for obtaining selectivity. In connection with developments in this area, this book contains updated and expanded versions of most of the lectures presented at a Cornett course held in Trieste (Italy) in 1989 and sponsored by the European Community. A primary aim is to cultivate a deeper understanding of the parameters that govern the selectivities and stimulate a wider utilization of transition metal based catalysis in organic synthesis. All aspects of selectivity, chemo-, regio-, stereo- and enantioselectivity are considered and illustrated by applications in various fields or organic synthesis. The impact of catalysis in oxydation, reduction, carbonylation reactions, carbene chemistry, in Ni and Pd promoted dimerizations, oligomerizations as well as fonctionalisations is stressed, quite often with special emphasis laid on reaction mechanisms. In this aspect, the last chapter examplifies the interest of high pressure NMR and IR when investigating the nature of reaction intermediates in homogeneous reactions.
The first extended analysis of selectivity policies of important bilateral and multilateral aid donors, this book combines a policy-analytical with a quantitative-empirical approach. Bringing out the conflicts that may exist between foreign assistance agendas and the desire of governments in developing countries to set priorities for their national
One of the most fundamental aspects of the auditory system is its frequency selectivity - the ability to resolve a complex sound into frequency compOhents. This ability plays a role in many aspects of auditory perception, including: the masking of one sound by another; the perception of pitch for pure tones and complex tones; the perception of timbre; the perception of the relative phase of components in complex sounds; and the perception of loudness. Over the last decade, there have been considerable advances in our understanding of frequency selectivity, both at the physiological and psychophysical level, and rapid progress continues to be made. This book summarizes the proceedings of a NATO Advanced Research Workshop on Auditory Frequency Selectivity which was held in Wolfson College, Cambridge from June 23rd to 27th, 1986. The Workshop brought together leading researchers from all disciplines relevant to the topic, with the aim of reviewing and consolidating the latest research findings, and identifying areas of uncertainty or controversy where further research is needed. The book is aimed primarily at research scientists and research students in the fields of psychology, audiology, auditory physiology, biophysics, medicine, acoustical engineering, noise control, communication and speech science. It should also be useful for advanced undergraduates in these disciplines. A feature of the book is that it includes summaries of the discussions which followed the presentation of each paper at the Workshop.
High profile cases before the European Commission and the EU courts have intensified scrutiny of the link between State aid law and the taxation of multinational enterprises. Certain decisions have raised questions about fiscal sovereignty and the interpretation of the rules on State aid – in particular the notion of selectivity, which have not been addressed in detail by existing research. The combination of the evolution of the notion of selectivity in State aid law, on the one hand, and the need to adapt the rules for the taxation of the profits of multinational enterprises to the modern economy, on the other hand, makes it necessary to assess whether existing as well as alternative rules for the allocation of the corporate tax base might entail a selective treatment. This book responds to the need of research in the area of State aid law applied to the taxation of the income of multinational enterprises, focusing on the crucial concept of selectivity. The analysis proceeds with a detailed investigation of the theoretical issues that arise when applying the selectivity test in State aid law to three methods for the allocation of the corporate tax base between the members of multinational enterprises: – the arm’s length principle; – transfer pricing safe harbours; and – systems of formula apportionment. This research project is conducted at a theoretical level, without considering national provisions or particular tax treaties. The author suggests an analytical framework on the application of the selectivity test to the three allocation methods. It is concluded that these methods are likely to have certain selective features, with varying possibilities to be justified by the inner logic of a corporate income tax system. It is also demonstrated that selectivity occurs for different reasons, due to the different rationales of the three allocation methods. This book is intended at contributing to the academic literature on the impact of State aid law on the principles for the taxation of the income of multinational enterprises. The outcome of this research project is also relevant for lawmakers who need to reconcile the imperatives of State aid law with the design of rules that match their tax policies, as well as for judges or lawyers who apply the rules on State aid to tax provisions.
