In the early 1950s it was proposed that the cationic centers of carboniun ions in the usual solvolytic media could diminish their electron deficiency by interacting with the

During the last decade there has been an increasing interest in clusters and small particles because of the peculiar proper ties induced by their large area to volume ratio. For that reason small particles are often considered as an intermediate state of matter at the border between atomic (or molecular) chemistry, and physics of the condensed matter. The importance of the surface effect can explain the anomalous properties, for example the exis tence of the five fold symmetry observed in different circumstan ces '(beams of rare gas clusters, gold particles deposited on a substrate). However the question of the critical size at which the transition to bulk properties occurs cannot be simply answered, since the reply depends on the peculiar property which is studied. The importance of the size effect was emphasized in the last International Meetings. However the situation remains confused in most cases since the exact role of the cluster environment cannot be clearly elucidated and is a main difficulty, except in cluster beam experiments. In fact ideally free clusters constitute a labo ratory exception. In most applications small particles must be supported on a surface or embedded in a matrix, in order to be stabilized, which obviously shows the role of the environment."

"SCIENCE AND TECHNOLOGY OF ' HE UNDEROLED MELT" This title was chosen as the topical headline of the Advanced Research Workshop (ARW) from March 17 to 22 1985, held at the Castle of Theuern. The usual term "Rapid Solidification" is an overlapping description. Due to the fact that nucleation is so eminently important for the undercooling of a melt and this, in turn, is an important characteristic of rapid solidifi cation, undercooling plays an essential role in "rapid solidification." The undercooled melt has caused an "accelerated evolution" (if not a revolution) in materials science during the last decade. Several rather exciting concepts with interesting potential for novel applications are being pursued presently in various laboratories and companies. They concern not only new processes and ha ware developments, but also present chal lenging perspectives for ventures, including the founding of new companies; or they promise growth possibilities with established larger and smaller industrial establishments."

Both experimental and theoretical investigations make it clear that mesoscale materials, that is, materials at scales intermediate between atomic and bulk matter, do not always behave in ways predicted by conventional theories of shock compression. At these scales, shock waves interact with local material properties and microstructure to produce a hierarchy of dissipative structures such as inelastic deformation fields, randomly distributed lattice defects, and residual stresses. A macroscopically steady planar shock wave is neither plane nor steady at the mesoscale. The chapters in this book examine the assumptions underlying our understanding of shock phenomena and present new measurements, calculations, and theories that challenge these assumptions. They address such questions as: - What are the experimental data on mesoscale effects of shocks, and what are the implications? - Can one formulate new mesoscale theories of shock dynamics? - How would new mesoscale theories affect our understanding of shock-induced phase transitions or fracture? - What new computational models will be needed for investigating mesoscale shocks?

valuable suggestions and constant help during the writing of the book, to Professor P. V. Gel'd for reading the manuscript and mak- ing valuable comments, and also to her colleagues in the Labora- tory for the Technology of Inorganic Compounds in the Institute for Problems in Materials Science of the Academy of Sciences of the Ukrainian SSR, in particular, to G. N. Makarenko, V. B. Fedorus, o. F. Kvas, and A. V. Tkachenko for assistance in planning the book and reading the manuscript. Contents Chapter I The Structure and Physi- chemical Properties of Carbides. . 1 Structures --. . . . . . . . . . . . . . -. -. . --. 1 Thermodynamic and thermophysical properties 22 Electrophysical and magnetic properties . . . . 30 Physicomechanical properties - . . - - . . . . . . 38 Chemical properties . . . . . . ---. . . --. -- 41 Chapter II Methods of Producing Carbides. . . 51 Chapter ITI Carbides of Metals of Group I -. . - 61 Carbides of the alkali metals . . . - . . - . - . . - 61 Carbides of metals of the copper subgroup. - - 66

An understanding of the processes involved in the basic and applied physics and chemistry of the interaction of plasmas with materials is vital to the evolution of technologies such as those relevant to microelectronics, fusion and space. The subjects dealt with in the book include: the physics and chemistry of plasmas, plasma diagnostics, physical sputtering and chemical etching, plasma assisted deposition of thin films, ion and electron bombardment, and plasma processing of inorganic and polymeric materials. The book represents a concentration of a substantial amount of knowledge acquired in this area - knowledge which was hitherto widely scattered throughout the literature - and thus establishes a baseline reference work for both established and tyro research workers.

This book seeks to provide a comprehensive coverage of the important and growing field of ladle metallurgy, including theory, practice, and economics. During the past decade, major advances have been made in the secondary metallurgy of steel and other metals; indeed, secondary metallurgy, that is, the ladle treatment of molten metals, following the melting and refining steps, has become an important and inevitable part of the overall processing sequence. Ladle metallurgy is attractive because it can provide an effective means for adjusting and fine-tuning the composition and temperature of the molten products prior to solidification processing. Ladle metallurgy allows us to produce materials of very high purity and will become increasingly an essential process requirement. Indeed, many of the novel casting techniques will mandate steels of much higher cleanliness than those in current practice. Of course, ladle metallurgy or secondary metallurgy is not limited to steel; indeed, major advances have been made and are being made in the secondary processing of aluminum, aluminum alloys, and many specialty metals.

Powders have been studied extensively because they arise in a wide variety of fields, ranging from soil mechanics to manufacture of pharmaceuticals. Only recently, however, with the deepening understanding of fractals, chaos, 1/f noise, and self-organization, has it been useful to study the mechanical properties of powders from a fundamental physical perspective. This book collects articles by some of the foremost researchers in the field, including chapters on: the role of entropy in the specification of a powder, by S.F. Edwards (Cambridge); discrete mechanics, by P.K. Haff (Duke); computer simulations of granular materials, by G.C. Barker (Norwich); pattern formation and complexity in granular flow, by R.P. Behringer and G.W. Baxter (Duke); avalanches in real sand piles, by A. Mehta (Birmingham); micromechanical models of failure, by M.J. Adams (Unilever) and B.J. Briscoe (Imperial College); mixing and segregation in particle flows, by J. Bridgwater (Birmingham); and hard-sphere colloidal suspensions, by P. Bartlett (Bristol) and W. van Megen (Melbourne).

The history of low dimensional conductors goes back to the prediction, more than forty years ago, by Peierls, of the instability of a one dimensional metallic chain, leading to what is known now as the charge density wave state. At the same time, Frohlich suggested that an "ideal" conductivity could be associated to the sliding of this charge density wave. Since then, several classes of compounds, including layered transition metal dichalcogenides, quasi one-dimensional organic conduc tors and transition metal tri- and tretrachalcogenides have been extensively studied. The molybdenum bronzes or oxides have been discovered or rediscovered as low dimensional conductors in this last decade. A considerable amount of work has now been performed on this subject and it was time to collect some review papers in a single book. Although this book is focused on the molybdenum bronzes and oxides, it has a far more general interest in the field of low dimensional conductors, since several of the molybdenum compounds provide, from our point of view, model systems. This is the case for the quasi one-dimensional blue bronze, especially due to the availability of good quality large single crystals. This book is intended for scientists belonging to the fields of solid state physics and chemistry as well as materials science. It should especially be useful to many graduate students involved in low dimensional oxides. It has been written by recognized specialists of low dimensional systems."

Because of a lack of appreciation for his efforts in developing modern polymer science, the contributions of Hermann Staudinger were disregarded for decades. There have also been delays in recognizing the contributions of other pioneers in polymer science. Hence, it is gratifying to note that Professor Seymour chaired an American Chemical Society Symposium focusing on the contributions of these pioneers and that Kluwer Academic Publishers has published the proceedings of this important symposium. H.Mark v DEDICATION This book on Pioneers in Polymer Science is dedicated to Nobel Laureate Polymer Scientists Hermann Staudinger, Emil Fischer, Herman Mark, Paul J. Flory, Linus Pauling, Carl S. Marvel, M. Polanyi, Giulio Natta, Karl Ziegler, and Bruce Merrifield as well as to those pioneers such as J.C. Patrick, Robert Thomas, William Sparks, Maurice Huggins, Qtto Bayer, Leo Baekeland, Anselm Payer, Roger Boyer, Waldo Semon, Robert Banks, J.P. Hogan, and other pioneers who, to a large degree, were responsible for the development of the world's second largest industry. ACKNOWLEDGEMENT The editor appreciates the contribution of co-authors Herman Mark, C.H. Fisher, and G. Alan Stahl who co chaired the Symposium on Pioneers in Polymer Science at the National Meeting of the American Chemical Society at Seattle, WA in 1984 and who contributed a chapter in this book. The editor is particularly grateful to Mischa Thomas who typed this manuscript."

In 1979 the first InternationalSymposium on Low CycleFatigue and Elasto-Plastic Behaviour of Materials was held in Stuttgart, FRG. Since then research in low cycle fatigue has proceeded rapidly. The vital interest of engineers and researchers in communicating the rapid advances in the ongoing research in low cycle fatigue has encouraged me to initiate again the Second International Conference which was held in Munich, FRG, 7-11 September 1987. Failure in low cycle fatigue represents a serious problem in the design and opera tion of highly stressed structures. Under complex loading and environmental cir cumstances, especially for high temperature services, reliable life prediction can not be expected without detailed consideration of the failure mechanism and with out extensive use of mechanistic approaches. The purpose of this conference was to provide a forum to discuss the advances in recent research in the field of low cycle fatigue. The conference was intended to help to further bridge the gap between those who are involved in basic research, and the engineers who have to perform the design of highly stressed structural components."

Research on metal-containing polymers began in the early 1960's when several workers found that vinyl ferrocene and other vinylic transition metal TI -complexes would undergo polymerization under the same conditions as conventional organic monomers to form high polymers which incorporated a potentially reactive metal as an integral part of the polymer structures. Some of these materials could act as semi conductors and possessed one or two dimensional conductivity. Thus applications in electronics could be visualized immediately. Other workers found that reactions used to make simple metal chelates could be used to prepare polymers if the ligands were designed properly. As interest in homogeneous catalysts developed in the late 60's and early 70's, several investigators began binding homogeneous catalysts onto polymers, where the advantage of homogeneous catalysis - known reaction mechanisms and the advantage of heterogeneous catalysis - simplicity and ease of recovery of catalysts could both be obtained. Indeed the polymer matrix itself often enhanced the selectivity of the catalyst. The first symposium on Organometallic Polymers, held at the National Meeting of the American Chemical Society in September 1977, attracted a large number of scientists interested in this field, both established investigators and newcomers. Subsequent symposia in 1977, 1979, 1983, and 1987 have seen the field mature. Hundreds of papers and patents have been published."

This conference, organised jointly by QMC Wolfson Fire & Materials Centre (Queen Mary College) and the Fire Research Station, held at the Tara Hotel in London, UK, was well attended by a wide range of experts in the production and use of polymer foams. Other experts concerned with research, development, testing, specifying, approving and purchasing products incorporating polymer foams for use in the construction, engineering and furniture industries were also present and contributed to the several valuable discussions on specific topics. The conference was successful and achieved its aim of infonning delegates of the fire characteristics of these materials and how they can be assessed in the light of the latest knowledge and technology. The papers presented a wide-ranging review of the main important cellular polymers and their applications in different environments where fire hazards have been encountered. Delegates accepted that there was a continuing need for major growth in the use of cellular polymers and therefore intensified research into development of improved test procedures, fire retardants and smoke suppressants was required.

The Army Materials and Mechanics Research Center in cooperation with the Office of Sponsored Programs of Syracuse University has been conducting the Annual Sagamore Army Materials Research Conferences since 1954. The specific purpose of these conferences has been to bring together scientists and engineers from academic institutions, industry and government to explore in depth a subject of importance to the Department of Defense, the Army, and the scientific community. This 30th Sagamore Conference, entitled Innovations in Materials Processing, has attempted to focus on the inter disciplinary nature of materials processing, looking at recent advancements in the development of unit processes from a range of standpoints from the understanding and control of the under lying mechanisms through their application as part of a manufactur ing sequence. In between, the classic link between processing and materials properties is firmly established. A broad range of materials are treated in this manner: metals, ceramics, plastics, and composites. The interdisciplinary nature of materials processing exists through its involvement with the basic sciences, with, process and product design, with process control, and ultimately with manufacturing engineering. Materials processing is interdisciplinary in another sense, through its application within all materials disciplines. The industrial community (and the Army as its customer) is becoming increasingly concerned with producibility/reliability/ affordability issues in advanced product development. These concerns will be adequately addressed only by employing the full range of disciplines encompassed within the field of materials processing."

Advances in Solar Energy is back on schedule. Volume III contains a number of interesting reviews of the different fields in solar energy conversion. We appreciate the many encouraging comments received after the second volume appeared and have incorporated some of the suggested changes. Even though most of the reviews are invited through our editors, we are always open to suggestion about subjects of importance that are ready for a com prehensive and critical review and have not been recently covered, or about potential authors. I would like to take this opportunity to thank Professor John A. Duffie for his invaluable help in starting the Advances in Solar Energy series. Although he has recently taken full responsibility as editor-in-chief for the Solar Energy Journal, his continued assistance as a member of the Board of Editors is greatly appreciated. The diligent work of the many active editors is gratefully acknowledged and constitutes the basis for a valuable review periodical with outstanding contributions. The typesetting was done by Sandra Pruitt in the Delaware office, using the TEX-program with laser print-out. Her organization and patience in coordinating with the authors, and her technical skill and diligence in preparing the submitted copy permitted the timely and high-quality assembly of this production. We wish to commend her for efforts well beyond the call of duty. The accommodating help from Plenum Press and its production staff deserves our grateful acknowledgement."

For many years it has been recognized that engineering materials that are-tough and ductile can be rendered susceptible to premature fracture through their reaction with the environment. Over 100 years ago, Reynolds associated hydrogen with detrimental effects on the ductility of iron. The "season cracking" of brass has been a known problem for dec ades, but the mechanisms for this stress-corrosion process are only today being elucidated. In more recent times, the mechanical properties of most engineering materials have been shown to be adversely affected by hydrogen embrittlement or stress-corrosion cracking. Early studies of environmental effects on crack growth attempted to identify a unified theory to explain the crack growth behavior of groups of materials in a variety of environments. It is currently understood that there are numerous stress-corrosion processes some of which may be common to several materials, but that the crack growth behavior of a given material is dependent on microstructure, microchemistry, mechanics, surface chemistry, and solution chemistry. Although the mechanism by which various chemical species in the environment may cause cracks to propagate in some materials but not in others is very complex, the net result of all environmentally induced fracture is the reduction in the force and energy associated with the tensile or shear separation of atoms at the crack tip."

As an instructor in various finishing courses, I have frequently made the statement over the years that "In the field of metal finishing there is very little black and white, just a great deal of grey. It is the purpose of the instructor to familiarize the student with the beacons that will guide him through this fog. " To a very considerable extent, a handbook such as this serves a similar purpose. It is also subject to similar limitations. Providing all the required information would result in a multi-volume encyclopedia rather than a usable handbook. In the pages that follow, you will therefore find frequent references to other sources where more detailed explanations or information can be found. The present goal is proper guidance and the provision ofthe most frequently required facts, not everything that is available. In the 13 years since the last edition, changes in the finishing industry have been profound but in one sense have resulted in simplifying matters rather than complicating them. Because technology has advanced to a level of complexity rendering "home brew" impracti cal in many cases, dependence on proprietary compounds has become common. Therefore, detailed solution compositions are often no longer significant or even practical. It is thus more important to provide instruction about the factors that affect the choice of the most suitable type of proprietary material."

The origin of this book can be traced to a Workshop held at the University of Cambridge in December 1985 under the auspices of the Wolfson Group for Studies of Fluid Flow and Mixing in Industrial Processes. This Group was es tablished at the University of Cambridge in January 1983 and includes mem bers from the Departments of Applied Mathematics and Theoretical Physics, Engineering and Chemical Engineering. As its name suggests, the objective of the Group is to undertake, co"ordinate and stimulate research in various aspects of fluid flow and mixing in industrial processes. However, another equally important aim for the Group is to promote co-operation between the University and industry at all levels from collaborative research projects to joint colloquia. The Workshop in December 1985 on 'Mixing, Stirring and Solidification in Metallurgical Processes' which led to this book was one in an annual series of such meetings first held in December 1983. The existence of the Wolfson Group is due to the enthusiasm of its original advocate, the late Professor J. A. Shercliff FRS, Head of the Department of Engineering who, together with Professor G. K. Batchelor FRS, Professor J. F. Davidson FRS, Dr J. C. R. Hunt, and Dr R. E. Britter, were responsible for the initial application to the Wolfson Foundation and for the subsequent direction of the Group's activities."

This book constitutes the Proceedings of the NATO Advanced Research Workshop on Conjugated Polymers held at the University of Mons, Belgium, during the first week of September 1989. The Workshop was attended by about fifty scientists representing most of the leading research groups within NATO countries, that have contributed to the development of conjugated polymeric materials. The program was focused on applications related to electrical conductivity and nonlinear optics. The attendance was well balanced with a blend of researchers from academic, industrial, and government labs, and including synthetic chemists, physical chemists, physicists, materials scientists, and theoreticians. The Workshop provided an especially timely opportunity to discuss the important progress that has taken place in the field of Conjugated Polymers in the late eighties as well as the enormous potential that lies in front of us. Among the recent significant developments in the field, we can cite for instance: (i) The discovery of novel synthetic routes affording conjugated polymers -that are much better characterized, especially through control of the molecular weight; - that can be processed from solution or the melt; the early promise that conducting polymcrs would constitute materials combining the electrical conductivities of metals with the mechanical properties of plastics is now being realized; -that can reach remarkably high conductivities.

Recently, considerable research effort has been devoted to the fabrication of structures by adhesive bonding due to its definite advantages compared with other conventional techniques such as casting and welding. With bonding the need for stress relieving is avoided, the lead time is reduced and the design can be carried out according to optimum principles with the ability to bond different materials: for example, aluminium to steel, plastics to metals. These advantages have led to continuous efforts in studying the mechanism of bonding, in improving the properties of structural of adhesive bonding in technically adhesives and in widening the use demanding industrial applications. The aim of this book is to present recent developments in the use of adhesive bonding in structural fabrication throughout the world, as illustrations to successful appli cation of this novel technique of fabrication. For industrial applications to be successful, the engineer should be aware ofthe various types of adhesives available and of their properties, and also of the new design philosophy to be adopted in such bonded structures, and a portion of the book is aimed at highlighting the properties of the adhesives and their suitability and at assisting the engineer in his choice of the proper adhesive for the job at hand. Also emphasised in this book are the various means of destructive and non-destructive testing of bonded joints, with special mention of structures fabricated by adhesive bonding."

Metal removal processes - cutting and grinding in this book - are an integral part of a large number of manufacturing systems, either as the primary manufacturing process, or as an important part of preparing the tooling for other manufacturing processes. In recent years, industry and educational institutions have concentrated on the metal removal system, perhaps at the expense of the process. This book concentrates on metal removal processes, particularly on the modeling aspects that can either give a direct answer or suggest the general requirements as to how to control, improve or change a metal removal process. This modeling knowledge is more important with automated computer controlled systems than it has ever been before, because quantitative knowledge is needed to design and operate these systems. This senior undergraduate/graduate textbook is aimed at providing the quantitative knowledge, often times at an elementary level, for handling the technological aspects of setting up and operating a metal removal process and interpreting the experience of planning, operating and improving a metal removal process based on rule of thumb approaches.

References Liquid-metal strain gages can be fabricated in either single- or delta-rosette configurations. Their main advantages are their low stiffness (essential for 1. Beatty, M.F. and Chewning, S. W., "Numerical Analysis of the Reinforcement Effect of a Strain Gage Applied to a Soft use on composites with soft, elastomeric matrices) Material," Int. J. Eng. Sci., 17, 907-915 (1979). and high elongation (at least 50 percent). Their prin 2. Pugin, V.A., "Electrical Strain Gauges for Measuring Large cipal disadvantages are a short shelf life and a Deformations," Soviet Rubber Industry, 19 (1), 23-26 (1960). nonlinear calibration curve. 3. Janssen, M.L. and Walter, J.D., "Rubber Strain Measurements in Bias, Belted Bias and Radial Ply Tires," J. Coated Fibrous Mat., 1, 102-117 (1971). 4. Patel, H.P., Turner, J.L., and Walter, J.D., "Radial Tire Cord-Rubber Composite," Rubber Chem. and Tech., 49, Acknowledgments 1095-1110 (1976). 5. Stone, J.E., Madsen, N.H., Milton, J.L., Swinson, W.F., and Turner, J.L., "Developments in the Design and Use of Liquid-Metal Strain Gages," EXPERIMENTAL MECHANICS, 23, The author acknowledges helpful suggestions by 129-139 (1983). Dr. Joseph D. Walter of Firestone Central Research 6. Whitney, R.J., "The Measurement of Volume Changes in Human Limbs, " J. Physiology, 121, 1-27 (1953)."

A comprehensive, up-to-date review of the physics and applications of a major class of laser, the most important example of which is the copper vapour laser. A collection of 50 papers written by the world's leaders in the field. Papers cover: the early history of pulsed metal vapour lasters; the plasma kinetics and excitation mechanisms of self terminating and recombination metal vapour lasers; beam quality issues for applications; frequency harmonic generation for mid-UV applications; high-precision processing of metals, ceramics, glasses and plastics using metal vapour lasers; applications in medicine, including oncology and dermatology; applications in science such as spectroscopy and mass spectrometry. A practical source of information on the physics, engineering and applications of metal vapour lasers. Audience: scientists, teachers and graduate researchers working in the fields of gas lasers, laser optics, gas discharges, optoelectronics and laser applications in industry, science and medicine.

Optics at the Nanometer Scale: Imaging and Storing with Photonic Near Fields deals with the fundamentals of and the latest developments and applications of near-field optical microscopy, giving basic accounts of how and under what circumstances superresolution beyond the half- wavelength Rayleigh limit is achieved. Interferometric and fluorescence techniques are also described, leading to molecular and even atomic resolution using light. The storage of optical information at this level of resolution is also addressed.

According to the late Professor Emeritus Seitaro Tsuboi, l the word 'hydrothermal' was used as early as 1849 by a British geologist, Sir Roderick Murchison (1792-187 I), in relation to the action of heated water in bringing about change in the earth's crust. The term abounds in later geological literature, and is most frequently met in connection with the processes that take place at a stage near the closing in the course of consolidation of magma. When a cooling magma reaches that stage, the residual liquid contains a large proportion of volatile components, chiefly water, and further cooling results in the formation of minerals of special interest or ore-deposits. A great concern of Tsuboi's as a petrologist was to elucidate the details of the nature of various actions involved in these 'hydrothermal processes', of which little was known. It is remarkable that, in the last few decades, extensive high-temperature and high-pressure experiments, in which water plays an important role, have become practicable in laboratories, owing to the development of new apparatus and new methods. As a result, the knowledge essential to the elucidation of 'hydrothermal processes' has been improved, but is still far from complete.