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Selected, peer reviewed papers from the 12th international conference Baltic Polymer Symposium 2012, September 19-22, 2012, Liepaja, Latvia

Since the pioneering publications on coordination chemistry by Lehn and Pedersen in the late 1960s, coupled with the more orthodox interest from the transition metal chemists on template reactions (Busch, 1964), the field of supramolecular chemistry has grown at an astonishing rate. The use of transition metals as essential constituents of multi-component assemblies has been especially sharp in recent years, since the metals are prone to quick and reversible redox changes, and there is a wide variety of metal--ligand interactions. Such properties make supramolecular complexes of transition metal ions suitable candidates for exploration as light--energy converters and signal processors. Transition Metals in Supramolecular Chemistry focuses on the following main topics: (1) metal controlled organization of novel molecular assemblies and shapes; (2) design of molecular switches and devices operating through metal centres; (3) supramolecular catalysts that mimic metalloenzymes; (4) metal-containing sensory reagents and supramolecular recognition; and (5) molecular materials that display powerful electronic, optoelectronic and magnetic properties.

The intellectual and utilitarian opportunities that lie at the frontiers of chemistry have been recently emphasized by the Pimentel Report. Such report recommends that in the field of chemical research priority should be given to'understanding chemical reactivity'and proposes initiatives aimed at the clarification of factors that control the rates of reaction and the development of new synthetic pathways for chemical change. In the broad field of chemical reactivity, a discipline that has grown with an extraordinary rate is photochemistry. Since the knowledge of the photochemical properties at the molecular level has made a substantial progress in the last few years, there is currently a trend to study more and more complex photochemical systems. In particular, an emerging and rapidly expanding branch of photochemistry is that concerning studies of assemblies of molecular components properly combined so as to obtain light-induced functions (supramolecular photochemistry). Although much of the current work in supramolecular photochemistry is fundamental in nature, it is clear that progress in this field will be most rewarding for several applications concerning the interaction of light with matter. In particular, it will allow us to pursue research aimed at the photochemical conversion of solar energy by means of artificial systems and to make progress towards futuristic branches of science called'photonics'(photo-generated electron migration processes on a molecular basis) and'chemionics'(design of components, circuitry, and information treatment at the molecular level).

Our knowledge of the photodegradation of polymers, chemical evolution, photosynthesis, visual perception and the biological effects of light depends heavily on our ability to elucidate the primary photochemical processes of macromolecules. This volume brings together for the first time from the fields of natural as well as synthetic polymers a group of reports dealing with macromolecular photochemistry. Since macromolecular photo­ chemistry is an expanding new field that crosses the boundaries between classical disciplines, the reader will encounter the employment of diverse scientific approaches and unfamiliar terminology. However, it has become increasingly apparent that researchers in these fields have much to learn from each other. Although this book is not intended to give a detailed survey of the photochemistry of macromolecules. it does represent the editor's perspective on the relationship between theory, kinetic studies and the synthesis aspects of photochemistry. The ideas expressed by the contributors offer a valuable com­ posite of theoretical and experimental approaches for those who are concerned with problems which have photochemical relevance, and show that investigators from different fields share many concepts and perhaps some common problems. This novel array of present knowledge should provide a basis for organizing and understanding photochemical information from chemistry, physics, biology and medicine. While of particular value to the research worker, the book also should be of interest to the graduate student about to embark on a problem in macromolecular photo­ chemistry.

How did life begin on the Earth? The units of life are cells, which can be defined as bounded systems of molecules that capture energy and nutrients from the environment -- systems that expand, reproduce, and evolve over time, often into more complex systems. This book is the proceedings of a unique meeting, sponsored by NATO and held in Maratea, Italy, that brought together for the first time an international group of investigators who share an interest in how molecules self-assemble into supramolecular structures, and how those structures may have contributed to the origin of life. The book is written at a moderately technical level, appropriate for use by researchers and by students in upper-level undergraduate and graduate courses in biochemistry and molecular biology. The overall interest of its subject matter provides an excellent introduction for students who wish to understand how the foundational knowledge of chemistry and physics can be applied to one of the most fundamental questions now facing the scientific community. The editors are pioneers in defining what we mean by the living state, particularly the manner in which simple molecular systems can assume complex associations and functions, including the ability to reproduce. Each chapter of the book presents an up-to-date report of highly significant research. Two of the authors received medals from the National Academy of Science USA in 1994, and other research reported in the book has been featured in internationally recognized journals such Scientific American, Time, and Discover.

On the day after the 1959 Cambridge Congress, during which the International Union of Pure and Applied Biophysics was founded, a biophysics section was formed within the Society of Physical Chemistry (Societe de Chimie Physique). Since then, three of the Society's annual meetings (the 11th, 17th, and 23rd) were devoted exclusively to the physico-chemical study of biological systems. The first of these was held in June 1961 at a hotel in Col de Voza, at the foot of an alpine glacier above Chamonix. The second, in May 1967, took place in the more learned setting of the venerable rooms of the National Museum of Natural History in Paris. The third - the one dealt with in the present volume - was recently held at Orleans-La Source in the newly built lecture theatres of the young University, which is near the great Institutes of the National Centre for Scientific Research (CNRS), on the Sologne plateau. These three stages are milestones of an evolution which characterises (at least schematically) the explosive evolution of biological physico-chemistry. The first colloquium, with the title'Deoxyribonucleic Acid: Structure, Synthesis and Functions', actually marks the first contact of the physical chemist with one of the then most prestigious biological macromolecules, the structure of which had just been discovered, and in this way celebrated one of the first and most striking successes of molecular biology.

From within complex structures of organisms and cells down to the molecular level, biological processes all involve movement. Muscular fibers slide on each other to activate the muscle, as polymerases do along nucleic acids for replicating and transcribing the genetic material. Cells move and organize themselves into organs by recognizing each other through macromolecular surface-specific interactions. These recognition processes involve the mu­ tual adaptation of structures that rely on their flexibility. All sorts of conformational changes occur in proteins involved in through-membrane signal transmission, showing another aspect of the flexibility of these macromolecules. The movement and flexibility are inscribed in the polymeric nature of essential biological macromolecules such as proteins and nucleic acids. For instance, the well-defined structures formed by the long protein chain are held together by weak noncovalent interac­ tions that design a complex potential well in which the protein floats, permanently fluctuating between several micro- or macroconformations in a wide range of frequencies and ampli­ tudes. The inherent mobility of biomolecular edifices may be crucial to the adaptation of their structures to particular functions. Progress in methods for investigating macromolecular structures and dynamics make this hypothesis not only attractive but more and more testable.

Proceedings of a Colloquium held at Orléans, France, July 5-9, 1982

The Twentieth Jerusalem Symposium reflected the high standards of these distinguished scientific meetings which convene once a year at the Israel Academy of Sciences and Humanities in Jerusalem to discuss a specific topic in the broad area of quantum chemistry and biochemistry. The Twentieth Jerusalem Symposium marked an auspicious occasion. commemorating two decades of this scientific endeavour. The topic at this year's Jerusalem Symposium was Large Finite Systems which constitutes a truly interdisciplinary subject of central interest in the broad areas of chemistry. physics. astrophysics and biophysics. The main theme of the Symposium was built around bridging the gap between molecular. surface and condensed matter chemical physics. Emphasis was placed on the interrelationship between the properties of large molecules. van der Waals complexes and clusters. focusing on the structure. dynamics of nuclear motion. quantum and thermodynamics size effects. the nature of electronic states and excited-state energetics and dynamics of large finite systems. The interdisciplinary nature of these research areas was deliberated by intensive and extensive interactions between scientists from different disciplines and between theory and experiment. This volume provides a record of the invited lectures at the Symposium.

This proceedings volume explores the pathways and mechanisms by which constituent residues interact and fold to yield native biological macromolecules (catalytic RNA and functional proteins), how ribosomes and other macromolecular complexes self-assemble, and relevant energetics considerations.At the week-long interactive conference, some 20 leading researchers reported their most pertinent results, confronting each other and an audience of more than 150 specialists from a wide range of scientific disciplines, including structural and molecular biology, biophysics, computer science, mathematics, and theoretical physics. The fourteen papers — and audience interaction — are edited and illustrated versions of the transcribed oral presentations.The proceedings have been selected for coverage in:

Macromolecular Microsymposia – 16 (Prague, 1976) is a collection of lectures presented at the 16th Microsymposium on Macromolecules (Advances in Scattering Methods), held in Prague on July 12-16, 1976. This book contains four chapters and begins with a survey of density fluctuations in amorphous and semicrystalline polymers. The next chapter provides experimental procedures for studying light scattering from polymer films. This chapter also describes the theory for scattering from spherulites and the procedures for correction for multiple scattering, truncation, and disorder, and illustrated for studies n polyethylene terephthalate films. These topics are followed by a discussion of the classical light scattering from polymer solutions. The last chapter considers the progress of techniques and instruments of light-scattering spectroscopy, with emphasis on advances made in photon correlation. This book will be of value to analytical and organic chemists and researchers.

Macromolecules covers the papers presented in the 27th International Symposium on Macromolecules that tackles themes that represent the trend of development in the field of macromolecular science. The book presents papers from qualified lecturers who discuss not only their work, but also the state of knowledge, developments, and applications in the field in which they are involved. The text covers topics ranging from polymer chemistry, polymer physics, to polymer technology that illustrate the diversity of the interest of researchers involved in polymer science and show the pluridisciplinarity nature of the field. The text will be of great interest to researchers and professionals who are concerned with the advances in macromolecular science.

The Novartis Foundation Series is a popular collection of the proceedings from Novartis Foundation Symposia, in which groups of leading scientists from a range of topics across biology, chemistry and medicine assembled to present papers and discuss results. The Novartis Foundation, originally known as the Ciba Foundation, is well known to scientists and clinicians around the world.

Macromolecular Chemistryâ€8 focuses on the molecular configuration of polymers, charge-transfer complexes, polymerization reactions, molecular weight fractionation, and polymer systems. The selection first offers information on molecular configuration in bulk polymers and control of monomer reactivity in copolymerization. Discussions focus on thermodynamic behavior of concentrated polymer solutions; direct measurement of molecular dimensions; and modification of monomer reactivity in radical copolymerization. The book also ponders on non-equimolar compositions from comonomer charge-transfer complexes and preparation of oligomers with functional end groups by polymerization reactions. The text examines cooperative interactions of complementary synthetic macromolecules in solutions and molecular weight fractionation on the basis of solubility. Topics include interactions of chemically complementary molecules and conformational transitions and methods for evaluating the molecular size distribution of the original polymer. The book also tackles alkylaluminium compounds in carbenium ion polymerization and thermodynamics of multicomponent polymer systems. The selection is a dependable reference for readers interested in the molecular configuration of polymers, complexes, and polymer systems.

Macromolecular Solutions: Solvent-Property Relationships in Polymers is a collection of papers presented at a symposium on Macromolecular Solutions, held New York City on August 23-28, 1981, sponsored by the American Chemical Society at its 182nd national meeting. This book is composed of 19 chapters and begins with discussions on the concept, application, and analysis of solubility parameters of polymers. The succeeding chapters deal with the role of solubility parameters in polymer coating design and stress cracking of nylon. Considerable chapters are devoted to the preparation, properties, reactions, and analysis of various polymers and copolymers. These topics are followed by surveys of the polymer-surfactant interaction effect on polymer solution properties and the effects of methanol-gasoline mixtures on elastomers. The final chapters describe the residual solvent content effect on dissolution kinetics of polymers; the application of excimer fluorescence to measure polymer-solvent interactions; and a general procedure for the calculation of thermodynamic properties of polymer solutions. This book will be of great value to polymer chemists, manufacturers, and researchers.

Macromolecular Chemistry — 11 is a collection of lectures presented at the International Symposium on Macromolecules (The Third Aharon Katzir-Katchalsky Conference) held in Jerusalem, Israel, on July 13-18, 1975. The papers explore a wide range of topics related to macromolecular chemistry, including polyelectrolytes, biologically active synthetic polymers, and spans of polymer chains. The use of polymers as chemical reagents is also considered. This book is comprised of 19 chapters and begins with an introduction to the close relation between polyelectrolytes and hydrophilic colloids. A survey of polyelectrolyte knowledge that has accumulated since about 1940 is also presented. The discussion then turns to biologically active synthetic polymers; polymers and other composites; theories of the condensed polymer state; polymer adsorption inferred from electrical double layer measurements; and mobility and conductivity of ions in and into polymeric solids. The structure and viscoelastic properties of ion-containing polymers in the solid state are also examined, along with the use of graphite insertion compounds as chemical reagents in organic chemistry. The results of research on chemical modification of cellulose are also presented. This monograph will be of interest to chemists.

Macromolecular Chemistry—9 provides information pertinent to the fundamental aspects of macromolecular chemistry. This book discusses the structure, properties, morphology, chemical reactions, and compatibility of polymers. Organized into 16 chapters, this book begins with an overview of the methods for the determination of polymer compatibility by means of the mutual solvent method and a light-scattering technique. This text then examines certain urethane systems that are suitable for application in products usually made of black reinforced rubber with cord reinforcement. Other chapters consider polycyclotrimerization as a route to the synthesis of polymers of different structures containing carbo- or hetero-cyclic rings in the chain. This book discusses as well the separation of a binary organic liquid mixture by hyperfiltration. The final chapter deals with a model for the growth of crazes in the presence of liquids. This book is a valuable resource for chemists, scientists, mechanical engineers, researchers, and laboratory workers.

Macromolecular Microsymposia–XII and XIII provides information pertinent to the fundamental aspects of polymers and polymer solutions. This book discusses the structures in polymer solutions and the transformations of functional groups in polymers. Organized into two parts encompassing 15 chapters, this book begins with an overview of the method for the determination of the structure of block copolymers in concentrated solution and in the dry state. This text then examines the liquid crystalline mesophases of the cholesteric type where one requirement is the existence of chiral single molecules. Other chapters consider phospholipids and glycolipids, which are significant component of the structure of many cell membranes. This book discusses as well the organized structures of some synthetic macromolecules in gels and solutions. The final chapter deals with the technique for studying the effect of the excluded volume on the probability of cyclic chain conformations. This book is a valuable resource for chemists.

Food macromolecules play a crucial role in the formulation of a wide range of food products such as beverages, bread, cheese, dressings, desserts, ice-cream, and spreads. This book presents the very latest research in the area and is unique in covering both proteins and polysaccharides in the same volume. Specifically it describes recent experimental and theoretical macromolecules in solutions, suspensions, gels, glasses, emulsions and foams. Food Macromolecules and Colloids takes a fundamental approach to complex systems, providing an understanding of the physico-chemical role of macromolecular interactions in controlling the behaviour of real and model food colloids. It gives special attention to adsorbed protein layers, the stability of emulsions and foams, and the viscoelasticity and phase behaviour of mixed polysaccharide systems, as well as to the rheology and microstructure of biopolymer gels, and the interaction of proteins with lipids and aroma compounds. This attractive, typeset publication gives exceptionally broad international coverage of the subject and will make interesting reading for postgraduates, lecturers and researchers with interests in food science, surface and colloid science and polymer science.

Structural Order in Polymers presents the increasing importance of the relationships between order in the chemical constitution and in the steric structure of the macromolecules and physical and chemical properties of the polymers. This book discusses the simple types of steric order found in biopolymers. Organized into three parts encompassing 16 chapters, this book begins with an overview of the structural regularity as a primary requisite for the crystallization of a polymer. This text then examines the structure of cellulose, which is the most significant structural stereoregular polymer. Other chapters consider the major concepts of the stereoregulation of propylene catalytic polymerization. This book discusses as well the factors that determine microstructure and stereospecifity in polymerization. The final chapter deals with the significant role that membranes and membrane-related processes play in solving many ecological problems. This book is a valuable resource for chemical engineers, chemists, physicists, scientists, and research workers.

Cytodifferentiation and Macromolecular Synthesis focuses on research on biosynthesis, structure, and morphology of cells. The book first discusses cytodifferentiation and macromolecular synthesis and genetic control of protein structure. The relationship of amino acid substitutions to the genetic code; comparison of gene and protein alterations; and suppressor mutations are described. The text also looks at genetic repression, allosteric inhibition, and cellular differentiation; epigenetic control of protein synthesis in cells; quantitative studies of protein synthesis in embryonic tissues; and chromosomes and cytodifferentiation. The book also discusses the morphological and chemical differentiation of plastids. The effect of light on plastid development; structure of mature chloroplast; morphological changes in the development of proplastid to the chloroplast; and inheritable factors that control plastids are described. The text also focuses on the collagen system, mechanisms of elongation, and tissue interaction and metabolic responses. The book is a valuable reference for readers wanting to conduct research on the complex nature of cells.