Elsevier bv jul 2001 (4 Ergebnisse)

Buch. Zustand: Neu. Neuware - In accordance with the developments in computation, theoretical studies on numerical schemes are now fruitful and highly needed. In 1991 an article on the finite element method applied to evolutionary problems was published. Following the method, basically this book studies various schemes from operator theoretical points of view. Many parts are devoted to the finite element method, but other schemes and problems (charge simulation method, domain decomposition method, nonlinear problems, and so forth) are also discussed, motivated by the observation that practically useful schemes have fine mathematical structures and the converses are also true.…

Buch. Zustand: Neu. Neuware - NMR is a growing technique which represents a generalized, spread, common tool for spectroscopy and for structural and dynamic investigation. Part of the field of competence of NMR is represented by molecules with unpaired electrons, which are called paramagnetic. The presence of unpaired electrons is at the same time a drawback (negative effect) and a precious source of information about structure and dynamics. New phenomena and effects are described which are due to the high magnetic fields and advances in the methodology. Solution NMR of Paramagnetic Molecules is unique in dealing with these matters. The scope is that of presenting a complete description, which is both rigorous and pictorial, of theory and experiments of NMR of paramagnetic molecules in solution. Pertinent examples are described. From the time dependent behaviour of electrons in the various metal ions including polimetallic systems to the hyperfine-based information, and from NMR experiments to constraints for solution structure determination. The book's major theme is how to perform high resolution NMR experiments and how to obtain structural and dynamic information on paramagnetic metal ion containing systems.…

Buch. Zustand: Neu. Neuware - In previous volumes in this series, Advances in Metal and Semiconductor Clusters, the focus has been on atomic clusters of metals, semiconductors and carbon. Fundamental gas phase studies have been surveyed, and most recently scientists have explored new materials which can be produced from clusters or cluster precursors. In this latest volume, the focus shifts to clusters composed primarily of non-metal molecules or atoms which have one or more metal atoms seeded into the cluster as an impurity. These clusters provide model systems for metal ion solvation processes and metal-ligand interactions.Metal-ligand bonding underlies the vast fields of organometallic chemistry, transition metal chemistry and homogeneous catalysis. Catalytic activity, ligand displacement reactions and photochemical activity depend on the specific details of metal-ligand bonding. Likewise, metal ions are ubiquitous in chemistry and biology and weaker electrostatic interactions play a leading role in their function. In solution, metals exist in different charge states depending on the conditions, and the solvation environment strongly influences their chemistry. Many enzymes have metal ions at their active sites, and electrostatic interactions influence the selectivity for metal ion transport through cell membranes. Metal ions (e.g., Mg+, Ca+) are deposited into the earth's atmosphere by meteor ablation, resulting in a rich variety of atmospheric chemistry. Similarly, metal ions ( Mg+) have been observed in planetary atmospheres and in the impact of the comet Shoemaker-Levy 9 on Jupiter. In various circumstances, the electrostatic interactions of metal ions determine the outcome of significant chemistry. Cluster chemistry has made significant contributions to the understanding of these stronger metal ligand interactions and weaker metal ion solvation interactions. In this volume, the authors explore a variety of work in these general areas, where new cluster science techniques in the gas phase have made it possible to synthesize new kinds of complexes with metals and to measure their properties in detail.…

Buch. Zustand: Neu. Neuware - The subject of aluminium and Alzheimer's disease has been plagued with controversy. This controversy has served to obscure much of the scientific research in this field, and subsequently has obscured the possibility that aluminium is a contributory factor in the aetiology of Alzheimer's disease. This book brings together many of the world's leading scientists researching aluminium and life and contains their critical summaries on the known facts about aluminium toxicity in man and to offer an opinion on the implications of this knowledge on a link between aluminium and Alzheimer's disease. The subject areas of the chapters were chosen to reflect the myriad of ways that aluminium is known to impact upon mammalian physiology and function and range from clinical studies, through animal models of disease to the detailed biochemistry of aluminium toxicity. Chapters are also included on epidemiology and other factors involved in the aetiology of Alzheimer's.This is the first time that this subject has been treated in such a comprehensive manner. The research detailed in each chapter, includes the latest research in the field, it has been critically appraised and this appraisal has been used by each author to present an informed opinion of its relevance to aluminium and Alzheimer's disease. The chapters are much more than reviews; they are a statement of the state of the art and of what the future may hold for research in this field. As a whole they show the high quality of research that has been carried out in our efforts to understand the toxicity of aluminium in man and that we are far away from discounting the possibility that aluminium is a contributory factor in the aetiology of Alzheimer's disease.…