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Books > Science & Mathematics > Chemistry > Inorganic chemistry
The second volume of the series on inorganic biochemistry and bio physics is singularly devoted to magnetic resonance on systems of high molecular complexity. Recently, there have been important advances in magnetic resonance studies of polymers; these advances touch on all aspects of magnetic resonance, both theoretical and applied. Particular emphasis is placed here on multipulse experiments. We believe such an report will be of considerable interest to the readers of our series owing to the importance of magnetic resonance techniques in the investigation of biopolymers. Ivano Bertini Harry Gray Series Editors Preface This book is a record of the Proceedings of the International Symposium on "Advanced Magnetic Resonance Techniques in Systems of High Molecular Complexity," which was held in Siena between 15 and 18 May 1985. The idea of the meeting is due to Proff. N.M. Atherton, G. Giacometti and E. Tiezzi with the aim of honouring the scientific personality of Prof. S.I. Weissman. The meeting has been organized with the assistance of a National Committee formed by R. Basosi, I. Bertini, P. Bucci, C. Corvaia, A. Gamba, G. Martini, G.F. Pedulli, P.A. Temussi, and C.A. Veracini. The invited lecturers responded enthusiastically and a comprehensive picture of the theoretical and practical aspects of magnetic resonance could be therefore provided. The book contains all the plenary lectures delivered during the meeting and also a wide selection among the huge amount of contributions collected by the organizers."
Explanation of the structure-property relationship of a given molecule is generally simple because the characteristics of the atomic groups and chemical bonds and the effects emerging from their interaction have long been known, both from theore- cal studies and numerous experimental results. In contrast, it is often difficult to analyze, estimate, and account for the structure-properties relationship in sup- molecules. The characteristics of supramolecules are governed both by the nature of the constituent molecules and by their configuration while the characteristics of the constituent molecules are usually evident as mentioned above; their configu- tions are difficult to control, predict, and accurately estimate because of insufficient knowledge regarding the intermolecular forces. Moreover, since most of the int- molecular forces constructing supramolecules are weak, the supramolecular str- ture may vary depending on various factors, such as modification of the molecular structure, auxiliaries, and experimental conditions. Thus, in order to obtain supramolecules with the desired structures and properties, theoretical investigations on the intermolecular forces and accumulation of experimental studies on the re- tionship between the supramolecular structure and properties are both important.
This volume contains a series of papers originally presented at the Symposium on Polymer Gels organized and sponsored by the Research Group on Polymer Gels, The Society of Polymer Science of Japan and co-sponsored by the Science and Technology Agency (ST A) and MIT , Japan. The Symposium took place at Tsukuba Science City on 18th and 19th September, 1989. Recognized experts in their fields were invited to speak and there was a strong attendance from government, academic and industrial research centers. The purpose of the Symposium was to review the state of the art and to present and discuss recent progress in the understanding of the behavioral properties of polymer gels and their application to biomedical, environmental and robotic fields. Most of the papers and related discussions concentrated on the swelling behavior of hydrogels and chemomechanical systems, both artificial and naturally occurring, in which external stimuli of a physical or chemical nature control energy transformation or signal transduction. The recent great interest in chemomechanical systems based on polymer gels has stimulated considerable effort towards the development of new sensors and actuators, controllable membrane separation processes, and delivery systems in which the functions of sensing, processing and actuation are all built into the polymeric network device. Artificial chemomechanical systems, through the use of environmentally sensitive polymer gels, are emerging as interesting materials for mimicking basic processes previously only confined to the biological world, and commercially viable applications are also foreseen in the not-too-distant future
Boron has all the best tunes. That may well be the first impression of the Group 13 elements. The chemical literature fosters the impression not only in the primary journals, but also in asteady outflowofbooks focussing more or less closely on boron and its compounds. The same preoccupation with boron is apparent in the coverage received by the Group 13 elements in the comprehensive and regularly updated volume of the Gmelin Handbook. Yet such an imbalance cannot be explained by any inherent lack ofvariety, interest or consequence in the 'heavier elements. Aluminium is the most abundant metal in the earth's crust; in the industrialised world the metal is second only to iron in its usage, and its compounds can justifiably be said to touch our lives daily - to the potential detriment of those and other lives, some would argue. From being chemical curios, gallium and indium have now gained considerably prominence as sources of compound semiconductors like gallium arsenide and indium antimonide. Nor is there any want ofincident in the chemistriesofthe heavier Group 13 elements. In their redox, coordination and structural properties, there is to be found music indeed, notable not always for its harmony but invariably for its richness and variety. Thisbook seeks to redress the balance with a definitive, wide-rangingand up-to-date review of the chemistry of the Group 13 metals aluminium, gallium, indium and thallium.
Adhesives in general and structural adhesives in particular are the subjects of much academic interest as well as commercial importance. Structural bonding, as a method of joining, offers a number of advantages over mechanical fastening. However, in order to achieve satisfactory results, the proper adhesive must be selected and the appropriate bonding procedures followed. The purpose of Structural Adhesives: Chemistry and Technology is to review the major classes of structural adhesives and the principles of adhesion and bonding as these relate to structural joints. Each chapter provides an overview of the topic under discussion with a list of references to the relevant literature. In addition to describing the chemistry involved, other aspects of structural adhesive technology are covered, such as formula tion, testing, and end uses. Some structural adhesives, especially epoxies and phenolics, have a long history of successful use and are now widely employed. Others, such as the structural acrylics and cyanoacrylates, are beginning to gain industrial acceptance. Urethanes and anaerobics have limited but important uses, while high-temperature adhesives are still largely in the research and development stage."
The intrinsic properties of a solid, i. e. , the properties that result from its specific structure, can be largely modified by crystallographic and chem ical defects. The formation of these defects is governed by the heat and mass transfer conditions which prevail on and near a crystal-nutrient in terface during crystallization. Hence, both the growth of highly perfect crystals and the preparation of samples having predetermined defect-induced (extrinsic) properties require a thorough understanding of the reaction and transport mechanisms that govern crystallization from vapors, solutions and melts. Crystal growth, as a science, is therefore mostly concerned with the chemistry and physics of heat and mass transport in these fluid-solid phase transitions. Solid-solid transitions are, at this time, not widely employed for high quality single-crystal production. Transport concepts are largely built upon equilibrium considerations, i. e. , on thermodynamic and phase equilibrium concepts. Hence to supply a "workable" foundation for the succeeding discussions, this text begins in Chapter 2 with a concise treatment of thermodynamics which emphasizes applications to mate rials preparation. After working through this chapter, the reader should feel at ease with often (particularly among physicists) unfamiliar entities such as chemical potentials, fugacities, activities. etc. Special sections on ther mochemical calculations (and their pitfalls) and compilations of thermochemi cal data conclude the second chapter. Crystal growth can be called. in a wide sense, the science and technology of controlling phase transitions that lead to (single crystalline) solids.
Radiationless transitions comprise an important class of physical phenomena occurring in the excited states of molecules. They affect the lifetimes of the ex cited states and govern primary photochemical and photophysical processes. Much effort has been devoted to the understanding of radiationless transi tions. Still, owing to recent advances, the field continues to attract attention. The demand for a book on the theory of these processes naturally arises in at tempting to comprehend a large body of literature, as the famous review article by K. F. Freed and the book by R. Englman do not encompass some issues of current interest. Our intent is to highlight the underlying physical principles and methods in such a way that the book both in its content and its presentation is instruc tive for a wide audience. The basic ideas are treated in simple mathematical terms intelligible to ex perimentalists and to readers unfamiliar with the field. Complicated theoret ical methods are always expounded from first principles, so that a knowledge of quantum mechanics and mathematics at the graduate-student level will enable the reader to easily follow the derivations. Experts will find efficient methods of calculating the transition rates, as well as new applications of quasiclassical methods and fresh treatments of standard problems. Details of measurements are not discussed, and experimental data are only invoked to illustrate the theory."
This volume chronicles the proceedings of the Symposium on Particles on Surfaces: Detection, Adhesion and Removal held under the auspices of the Fine Particle Society in San Francisco, July 28-August 2, 1986. The study of particles on surfaces is extremely important in many areas of human endeavor (ranging from microelectronics to optics to biomedical). A complete catalog of modern precision and sophisticated technologies where particles on surfaces are of cardinal importance will be prohibitively long, but the following eclectic examples should underscore the concern about particles on a variety of surfaces. In the semiconductor world of shrinking dimensions, particles which, a few years ago, were cosmetically undesirable but functionally innocuous can potentially be killer defects now. As the device sizes get smaller, there will be more and more concern about smaller and smaller particles. In the information storage technology, the gap between the head and the disk is very narrow, and if a particle is trapped in the gap that can have very grave consequences. The implications of particulate contamination on sensitive optical surfaces is all too manifest. So the particulate contamination on surfaces is undesirable from functional, yield and reliability points of view. This symposium was organized with the following objectives in mind: to bring together active practitioners in this field; to provide a forum for discussion of the latest research and development activities in this area; to provide opportunity for cross-pollination of ideas; and to highlight topics which needed intensified effort.
Environmental pollution is one of the main problems to confront humanity, with the heavy metals occupying a leading role among the most pernicious pollutants. The metals cause cancer and other sicknesses. Their cytotoxic, mutagenic and carcinogenic potentials are not fully understood, and any thorough investigation demands the combined efforts of scientists drawn from many different disciplines. But the effects of heavy metals are not all negative: some, like cis-DDP, and some ruthenium and tin complexes, have antitumour activity. The idea underlying the present work is therefore to present a multidisciplinary perspective on heavy metals in the environment, affording a better understanding of their action on human organisms and health, aiming to make them less polluting and more environmentally friendly.
This book by Kaplan and Vekhter brings together the molecular world of the chemist with the condensed matter world of the physicist. Prior to the collapse of the Soviet Union, chemists in the West devoted lit to relationships between molecular electronic structure and tle attention solid-state vibronic phenomena. Treating quantum mechanical problems wherein the adiabatic Born-Oppenheimer approximation fails was done by "brute force. " With bigger and better computers available in the West, molecular orbital calculations were done on observed and conceived static structures with little concern for any cooperativity of vibrational behavior that might connect these states. While it had long been understood in the West that situations do occur in which different static structures are found for molecules that have identical or nearly identical electronic structures, little attention had been paid to understanding the vibrational states that could connect such structures. It was easier to calculate the electronic structure observed with several possible distortions than to focus on ways to couple electronic and vibrational behavior. In the former Soviet Union, computational power was not as acces sible as in the West. Much greater attention, therefore, was devoted to conserving computational time by considering fundamental ways to han dle the vibrational connectivity between degenerate or nearly degenerate electronic states.
All existing introductory reviews of mineralogy are written accord ing to the same algorithm, sometimes called the "Dana System of Mineralogy." Even modern advanced handbooks, which are cer tainly necessary, include basic data on minerals and are essentially descriptive. When basic information on the chemistry, structure, optical and physical properties, distinguished features and para genesis of 200-400 minerals is presented, then there is practically no further space available to include new ideas and concepts based on recent mineral studies. A possible solution to this dilemma would be to present a book beginning where introductory textbooks end for those already famil iar with the elementary concepts. Such a volume would be tailored to specialists in all fields of science and industry, interested in the most recent results in mineralogy. This approach may be called Advanced Mineralogy. Here, an attempt has been made to survey the current possibilities and aims in mineral matter investigations, including the main characteristics of all the methods, the most important problems and topics of mineral ogy, and related studies. The individual volumes are composed of short, condensed chap ters. Each chapter presents in a complete, albeit condensed, form specific problems, methods, theories, and directions of investigations, and estimates their importance and strategic position in science and industry."
An overview of modern organometallic thermochemistry, made by some of the most active scientists in the area, is offered in this book. The contents correspond to the seventeen lectures delivered at the NATO ASI Energetics of Organometallic Species (Curia, Portugal, September 1991), plus three other invited contributions from participants of that summer school. These papers reflect a variety of research interests, and discuss results obtained with several techniques. It is therefore considered appropriate to add a few preliminary words, attempting to bring some unity out of that diversity. In the first three chapters, results obtained by classical calorimetric methods are described. Modern organometallic thermochemistry started in Manchester, with Henry Skinner, and his pioneering work is briefly surveyed in the first chapter. The historical perspective is followed by a discussion of a very actual issue: the trends of stepwise bond dissociation enthalpies. Geoff Pilcher, another Manchester thermochemist, makes, in chapter 2, a comprehensive and authoritative survey of problems found in the most classical of thermochemical techniques - combustion calorimetr- applied to organometallic compounds. Finally, results from another classical technique, reaction-solution calorimetry, are reviewed in the third chapter, by Tobin Marks and coworkers. More than anybody else, Tobin Marks has used thermochemical values to define synthetic strategies for organometallic compounds, thus indicating an application of thermochemical data of which too little use has been made so far.
Crystal pulling is an industrial process and provides the bulk of semiconductor crystals for the semiconductor industry. Initially a purely empirical process, the increase in importance and size of the industry has led to basic research into the fundamentals of the process - particularly the modelling of heat and mass transfer. The book has been written by the recognized authority on Czochralski crystal-growth techniques. It is an attempt to strengthen the interface between the practical crystal grower and the applied mathematician involved in analytical and computer modelling. Its focus is on the physics, chemistry and metallurgy of the process. From reviews: "... There is a need for a modern, non-trivial text on Czochralski growth ... and Dr. Hurle is eminently suited to write such a text."; "Dr. Hurle is probably uniquely qualified to write a book on ... (the Czochralski) growth process. ... He has published a great deal of very substantial as well as innovative work in this area."
This first International Workshop on Auger Spectroscopy and Electronic Struc ture - IWASES 1, held in Giardini-Naxos, Sicily, Italy, grew out of a number of longstanding collaborations between the various Institutes of Physics of the University of Messina, namely the Institute of the Structure of Matter, the In stitute of Theoretical Physics and the Institute of General Physics, and groups in other European countries at the University of Liverpool, England, the Insti tute of Physical Chemistry, University of Munich, and the Fritz Haber Institute of the Max Planck Society, Berlin, FRG. This workshop was the first to be devoted solely to Auger electron spectroscopy. This initiative was motivated by the enormous evolution of the field within the last decade to a point where it now extends far beyond the mere application of this spectroscopy as an analytical tool to determine surface cleanliness and surface composition. In fact, the Auger process, which is a multi-electron process, and which leaves the sample in a doubly (or higher) ionized state, is an invaluable probe for investigating excited states and, in particular, electron (or hole) correlation effects. These correlation effects play an important role for many physical prop erties of matter such as magnetism, screening processes, and electron stimulated desorption (ESD), to name but a few."
Mixed valency is one of various names used to describe compounds which contain ions of the same element in two different formal states of oxidation. The existence of mixed valency systems goes far back into the geological evolutionary history of the earth and other planets, while a plethora of mixed valency minerals has attracted attention since antiquity. Indeed, control of the oxidation states of Fe in its oxides (FeO, Fe304' Fe203) was elegantly used in vase painting by the ancient Greeks to produce the characteristic black and red Attic ceramics (Z. Goffer, "Archaeological Chemistry," Wiley, New York, 1980). It was, however, only 25 years ago that two reviews of mixed valency appeared in the literature almost simultaneously, signalling the first attempt to treat mixed valency systems as a separate class of compounds whose properties can be correlated with the molecular and the electronic structure of their members. Then mixed valency phenomena attracted the interest of disparate classes of scientists, ranging from synthetic chemists to solid state physicists and from biologists to geologists. This activity culminated with the NATO ASI meeting in Oxford in 1979. The 1980's saw again a continuing upsurge of interest in mixed valency. Its presence is a necessary factor in the search for highly conducting materials, including molecular metals and superconductors. The highly celebrated high T c ceramic superconducting oxides are indeed mixed valency compounds.
The study of crystal structures has had an ever increasing impact on many fields of science such as physics, chemistry, biology, materials science, medicine, pharmacy, metallurgy, mineralogy and geology. Particularly, with the advent of direct methods of structure determination, the data on crystal structures are accumulating at an unbelievable pace and it becomes more and more difficult to oversee this wealth of data. A crude rationalization of the structures of organic compounds and the atom coordinations can be made with the well-known Kekule model, however, no such generally applicable model exists for the structures of inorganiC and particularly intermetallic compounds. There is a need to rationalize the inorganic crystal structures, to find better ways of describing them, of denoting the geometrical relationships between them, of elucidating the electronic factors and of explaining the bonding between the atoms with the aim of not only having a better understanding of the known structures, but also of predicting structural features of new compounds.
Modular Chemistry: the First Steps In recent years, there has been increasing interest among chemists, physicists, materials scientists, biologists, engineers, and others in the assembly of well defmed, relatively large functional structures from repetitive units that themselves are molecules of some complexity. Using the dictionary defmition of a module (a detachable section, compartment, or unit with a specific purpose or function, and in electronics, a compact assembly functioning as a component of a larger unit) [1], we feel that this newly emerging field of endeavor could be called "modular chemistry" [2]. The NATO Advanced Research Workshop on Modular Chemistry that was held on September 9 to 12, 1995, at Aspen Lodge near Estes Park, Colorado, was meant to bring together prominent contributors to modular chemistry as it is being born, and to examine the associated birth pangs. It was concluded that although real, these are not nearly as bad as giving birth to a hedgehog tail first, and that the ultimate rewards were likely to be far more satisfying in terms of new ideas and enabling methodology. The level of excitement about the possibilities that are opening up for modular chemists, and also the challenge involved, are perhaps best documented by noting that the planned discussion periods at the workshop were as long as the oral presentation periods, and yet, each discussion ran over the allocated time.
The International Winter School on Electronic Properties of High-Temperature Superconductors, held between March 7-14, 1992, in Kirchberg, (Tyrol) Austria, was the sixth in a series of meetings to be held at this venue. Four of the earlier meetings were dedicated to issues in the field of conducting polymers, while the winter school held in 1990 was devoted to the new discipline of high-T c superconductivity. This year's meeting constituted a forum not only for the large number of scientists engaged in high-Tc research, but also for those involved in the new and exciting field of fullerenes. Many of the issues raised during the earlier winter schools on conducting polymers, and the last one on high-T c superconductivity, have taken on a new significance in the light of the discovery of superconducting C materials. 60 The Kirchberg meetings are organized in the style of a school where expe rienced scientists from universities, research laboratories and industry have the opportunity to discuss their most recent results, and where students and young scientists can learn about the present status of research and applications from some of the most eminent workers in their field. In common with the previous winter school on high-Tc superconductors, the of the cuprate superconductors. present one focused on the electronic properties In addition, consideration was given to related compounds which are relevant to the understanding of the electronic structure of the cuprates in the normal state, to other oxide superconductors and to fulleride superconductors.
This book is intended to collect in one place as much information as possible on the use of EPR spectroscopy in the analysis of systems in which two or more spins are magnetically coupled. This is a field where research is very active and chemists are elbow-to-elbow with physicists and biologists in the forefront. Here, as in many other fields, the contributions coming from different disciplines are very important, but for active researchers it is sometimes difficult to follow the literature, due to differences in languages, and sources which are familiar to, e. g. , a physicist, are exotic to a chemist. Therefore, an effort is needed in order to provide a unitary description of the many different phenomena which are collected under the title. In order to define the arguments which are treated, it is useful to state clearly what is not contained here. So we do not treat magnetic phenomena in conductors and we neglect ferro- and antiferromagnetic resonance. The basic foundations of EPR spectroscopy are supposed to be known by the reader, while we introduce the basis of magnetic interactions between spins. In the first two chapters we review the foundations of exchange interactions, trying to show how the magnetic parameters are bound to the electronic structure of the interacting centers.
Carbosilanes are compounds in which the elements silicon and carbon alternate in the molecular skeleton [1]. Just as the alkanes are formally derived from the diamond lattice and the aromatics from the graphite lattice, the carbosilanes are structurally derived from silicon carbide. Because of the tetravalent nature of silicon and carbon we can expect stable linear, cyclic and polycyclic compounds to occur. However, carbosilanes do not exist in nature. This book is an attempt to give a summarized presentation. Carbosilanes are, of course, part" of organosilicon chemistry, but their behavior differentiates them distinctly from other organosilicon compounds. The differences result primarily from the alternating Si-C-Si arrangements in the molecular skeleton, and especially the various methylene bridges (CH , CHX, CX ; X = halogen) cause changes in z z Si-C bond polarization and hence influence the reaction possibilities. It is convenient to regard carbosilanes as similar to silicones except that the oxygen bridges of silicones are replaced by methylene units. However, this does not accurately account for all the chemical properties of these compounds. Carbosilanes are related more directly to silicon carbide, as shown occasionally by the reactive behavior of polycyclic car bosilanes. Therefore, in view of the present interest shown for thermally stable cera mics of unusual character, interesting possibilities arise for further development. Most cyclic carbosilanes can be classified in two groups: the carborundanes and the Si-scaphanes. Compounds belonging to the carborundane class maintain Si-C six-membered rings in the boat conformation.
Remarks by JVS. Volumes 1 and 2 of Feldspar Minerals were published in 1974, but Volume 3 was not completed because I was forced to devote 3 years to the resolution of unforeseen problems in the construction of an ion probe. By 1977, the incomplete draft for Volume 3 had become obsolete because of the enormous advances in knowledge of feldspars, particularly those in lunar rocks and meteorites, and in both deep-seated and ancient terrestrial rocks. Furthermore, it soon became obvious that a completely new version of Feldspar Minerals was needed because of the important new results on the physical and chemical properties. I had kept up with the interesting but tedious chore of weekly reading of the incoming literature and maintenance of the files. By 1980, the intense day-to day pressure had gone from my research programs on lunar rocks and on the development of the ion microprobe as a quantitative geochemical instrument, and I began preparation of a second edition of Feldspar Minerals."
The discovery of the antitumour activity of cisplatin in 1965 and its subsequent introduction into clinical trials in 1971 was the catalyst for a major international research effort investigating the potential of metal compounds in cancer therapy. Cisplatin now occupies an important place in the armamentarium of the oncologist due to its effectiveness in the treatment of testicular cancer. A second generation analogue, carbo platin, offers reduced toxicity together with therapeutic activity, which gives it a place in the front-line therapy of genitourinary cancers. These and other successes have encouraged the search for novel metal-based drugs for cancer therapy. Research has shown that metal compounds have potential for activity not only as cytotoxic antitumour agents, but also in areas such as adjuvant therapy, diagnosis and immunotherapy. The aim of this book is to review and describe the major achievements and developments arising from this international research effort. The contributing authors come from labora tories throughout Europe and America and represent the many disci plines characteristic of this research, such as clinical research, pharmacology, tumour biology and inorganic medicinal chemistry."
The effects of heat and light on chemical reactions have long been known and un derstood. Ultrasound has been known to promote chemical reactions for the past 60 years, but despite this, it did not attract the attention of synthetic chemists until recently. This arose historically from early studies which concentrated almost exclu sively on reactions in aqueous media and was also, in some measure, due to the availability of suitable technology. Since the early 1980s a plethora of literature has appeared of direct interest to synthetic chemists and the field has been developing rapidly. The aim of this book is to bring the background of this fascinating field to the atten tion of a wider audience. It explores the literature to date and attempts to indicate other areas in which ultrasound may be exploited. It also hopes to explode some of the myths surrounding this area which have hitherto been regarded by the synthetic community as a bit of a black art! Existing books and reviews have tended to concentrate on the physics of sonochem istry and to catalogue the instances in which ultrasound has proved useful in tack ling synthetic problems. Our aim has been to stress the relevance of this technique to synthetic chemists and we have included a section which deals with the practical aspects of carrying out these reactions.
This issue of Zeitschrift fUr Physik D contains papers which were presented at the 5th International Symposium on Small Particles and Inorganic Clusters. ISSPIC5 was held at the University of Konstanz, Germany, from September 10 to 14, 1990. There were 33 invited talks, and 295 papers were contributed. 14 particularly interesting papers had been selected by the International Advisory Board: they were presented during one of the regular sessions. In addition, two last-minute contributions, describing break throughs in the synthesis and characterization of size-selected fullerene carbon clusters, were communicated orally. The other contributions were presented during two poster sessions, comprising nearly twice as many papers as during the previous symposium in Aix-en-Provence, in 1988. Approximately 250 manuscripts were received, and all were refereed during the sympo sium. Several of them had to be revised, but only a small number were rejected. The contributions in this volume are grouped according to the topic, roughly following the scheme adopted during the conference."
In this brief, Mary Virginia Orna details the history of color from the chemical point of view. Beginning with the first recorded uses of color and ending in the development of our modern chemical industry, this rich, yet concise exposition shows us how color pervades every aspect of our lives. Our consciousness, our perceptions, our useful appliances and tools, our playthings, our entertainment, our health, and our diagnostic apparatus - all involve color and are based in no small part on chemistry. |
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