This book documents the proceedings of the symposium, "Mineral Scale Formation and Inhibition," held at the American Chemical Society Annual Meeting August 21 to 26, 1994, in Washington, D. C. The symposium, sponsored by the Division of Colloid and Surface Chemistry, was held in honor of Professor George H. Nancollas for his pioneering work in the field of crystal growth from solution. A total of 30 papers were presented by a wide spectrum of scientists. This book also includes papers that were not presented but were in the symposium program. The separation of a solid by crystallization is one of the oldest and perhaps the most frequently used operations in chemistry. Because of its widespread applicability, in recent years there has been considerable interest exhibited by academic and industrial scientists in understanding the mechanisms of crystallization of sparingly soluble salts. The salt systems of great interest in industrial water treatment area (i. e., cooling and boiler) include carbon ates, sulfates, phosphates, and phosphonates of alkaline earth metals. Although not as common as calcium carbonate and calcium sulfate, barium and strontium sulfates have long plagued oil field and gas production operations. The build-up of these sparingly soluble salts on equipment surfaces results in lower heat transfer efficiency, increased corrosion rates, increased pumping costs, etc. In the laundry application, insoluble calcium carbonate tends to accumulate on washed fabrics and washing equipment parts, resulting in undesirable fabric-encrustation or scaling."

Stability constants are fundamental to understanding the behavior of metal ions in aqueous solution. Such understanding is important in a wide variety of areas, such as metal ions in biology, biomedical applications, metal ions in the environment, extraction metallurgy, food chemistry, and metal ions in many industrial processes. In spite of this importance, it appears that many inorganic chemists have lost an appreciation for the importance of stability constants, and the thermodynamic aspects of complex formation, with attention focused over the last thirty years on newer areas, such as organometallic chemistry. This book is an attempt to show the richness of chemistry that can be revealed by stability constants, when measured as part of an overall strategy aimed at understanding the complexing properties of a particular ligand or metal ion. Thus, for example, there are numerous crystal structures of the Li+ ion with crown ethers. What do these indicate to us about the chemistry of Li+ with crown ethers? In fact, most of these crystal structures are in a sense misleading, in that the Li+ ion forms no complexes, or at best very weak complexes, with familiar crown ethers such as l2-crown-4, in any known solvent. Thus, without the stability constants, our understanding of the chemistry of a metal ion with any particular ligand must be regarded as incomplete. In this book we attempt to show how stability constants can reveal factors in ligand design which could not readily be deduced from any other physical technique.

Syracuse University and the Army Materials and Mechanics Research Center of Watertown, Massachusetts have conducted the Sagamore Army Materials Research Conference since 1954. In ce1ebration of the 25th Anniversary of this conference, these proceedings are dedicated to the founding members of the Sagamore Conferences. They are Prof. Dr. George Sachs, Dr. James L. Martin, Colonel Benjamin S. Mesik, Dr. Reinier Beeuwkes, Mr. Norman L. Reed and Dr. J. D. Lubahn. This vo1ume, ADVANCES IN METAL PROCESSING, addresses Rapid Solidification Processing, Powder Processing and Conso1idation, We1ding and Joining, Thermal and. Mechanica1 Processing, Meta1 Removal and Process Mode1ing. The dedicated assistance of Mr. Joseph M. Bernier of the Army Materials and Mechanics Research Center and He1en Brown DeMascio of Syracuse University throughout the stages of the conference p1anning and fina11y the pub1ication of this book is deep1y appreciated. Syracuse University Syracuse, New York The Editors vii CONTENTS OVERVIEW Materials Processing - A Perspective of the Field 1 M.C. Flemings and R. Mehrabian SESSION I RAPID SOLIDIFICATION PROCESSING B.B. Rath, Moderator Heat Flow Limitations in Rapid Solidification Processing . . . . . . . . . . . 13 R. Mehrabian, S.C. Hsu, C.G. Levi, and S. Kou Laser Processing of Materials . . . . . 45 B.H. Kear, E.M. Breinan, and E.R. Thompson Electrohydrodynamic Techniques in Metals 79 Processing . . . . . . . . . . ."

Science is not a mere collection of facts. It is the correlation of facts, the interpretative synthesis of the available knowledge and its application that excite the imagination of a scientist. Even in these days of modern technology, the need for quick and accurate dissemination of new information and current concepts still exists. Conferences and Symposia offer one direct method of communication. The Summer Schools are another approach. The success of a Summer School is mainly due to that human factor and under standing that goes with it and allows for extensive and often time-unrestricted discussions. During the course of the past 20 years, one of the most in tensively studied groups of elements in the Periodic Table is the Lanthanides. In this period, we have increased our knowledge on these once exotic elements, which were once considered to be a part of a lean and hungry industry, many-fold due to the involve ment of scientists from various disciplines. The purpose of our Summer School was to bring a group of ex perts and participants together for the exchange of ideas and in formation in an informal setting and to promote interdisciplinary interactions. Out of many conceivable topics, we selected the following five as the main basis to broaden our knowledge and understanding I) Systematics 2) Structure 3) Electronic and Magnetic Proper ties 4) Spectroscopic Properties and 5) Lanthanide Geochemistry."

Iron Acquisition by the Genus Mycobacterium summarizes the early evidence for the necessity of iron in mycobacteria and the discovery of the mycobacterial siderophores mycobactin, carboxymycobactin, and exochelin. The structural characterization of the mycobacterial siderophores is described. The genes so far identified as essential for iron acquisition and maintenance of an infection by pathogenic mycobacteria are discussed. The potential role of siderocalin in iron gathering by M. tuberculosis is featured. Because new drugs for M. tuberculosis are needed, this brief also emphasizes the design of antibiotics that interfere with siderophore biosynthesis and the use of siderophore analogs and/or conjugates.

Mechanisms of Inorganic and Organometallic Reactions provides an ongoing critical review of the primary literature concerned with mechanisms of inorganic and organometallic reactions. The main focus is on reactions in solution, although solid-state and gas-phase studies are included where they provide relevant mechanistic insight. Each volume covers an eighteen-month literature period, and this, the eighth volume in the series, includes papers published during January 1990 through June 1991. Where appropriate, references to earlier reports and to specific sections in previous volumes are given. Coverage spans the whole area as comprehensively as possible in each volume, and while it is impossible to be absolutely exhaustive, every effort is made to include all of the important published work that is relevant to the elucidation of reaction mechanisms. Numerical data are reported in the units used by the original authors, and they are converted to common units only when comparisons are being made. The successful format of earlier volumes is retained to facilitate tracing progress over several years in a particular topic, and the series now permits this to be done for a twelve-year period. The introduction three volumes ago of computerized techniques to improve cross-referencing in the Index brought positive reader comments, and their use is being continued.

During the past few decades, much research has been reported on the formation of insoluble monomolecular films of lipids and biopolymers (synthetic polymers and proteins) on the surface of water or at the oil-water interface. This interest arises from the fact that monomolecular film studies have been found to provide much useful information on a molecular scale, information that is useful for understanding many industrial and biological phenomena in chemical, agricultural, pharmaceutical, medical, and food science applications. For instance, information obtained from lipid monolayer studies has been useful in determining the forces that are known to stabilize emulsions and biological cell membranes. The current texts on surface chemistry generally devote a single chapter to the characteristics of spread monolayers of lipids and biopolymers on liquids, and a researcher may have to review several hundred references to determine the procedures needed to investigate or analyze a particular phenomenon. Furthermore, there is an urgent need at this stage for a text that discusses the state of the art regarding the surface pheqomena exhibited by lipids and biopolymers, as they are relevant to a wide variety of surface and interfacial processes.

Focusing on practical applications, the author provides a balanced introduction to the many possible technological uses of metal complexes. Coverage includes the transition metals, lanthanide and actinide complexes, metal porphyrins, and many other complexes. This volume meets the needs of students and scientists in inorganic chemistry, chemical physics, and solid-state physics.

Over the past fifteen years the Commission on Equilibrium Data of the Analytical Division of the I nter national Union of Pure and Applied Chemistry has been sponsoring a noncritical compilation of metal complex formation constants and related equilibrium constants. This work was extensive in scope and resulted in the publication of two large volumes of Stability Constants by the Chemical Society (London). The first volume, edited by L. G. Si"en (for inorganic ligands) and by A. E. Marte" (for organic ligands), was published in 1964 and covered the literature through 1962. The second volume, subtitled Supplement No.1, edited by L. G. Si"en and E. Hogfeldt (for inorganic ligands) and by A. E. Marte" and R. M. Smith (for organic ligands), was published in 1971 and covered the literature up to 1969. These two large compilations attempted to cover a" papers in the field related to metal complex equilibria (heats, entropies, and free energies). Since it was the policy of the Commission during that period to avoid decisions concerning the quality and reliability of the published work, the compilation would frequently contain from ten to twenty values for a single equilibrium constant. In many cases the values would differ by one or even two orders of magnitude, thus frustrating readers who wanted to use the data without doing the extensive literature study necessary to determine the correct value of the constant in question."

The phenomenon of catalysis is found in many homogeneous and heterogeneous systems undergoing chemical change, where it effects the rates of approach to the equilibrium state in processes as diverse as those found in the stars, the earth's mantle, living organisms, and the various chemistries utilized by industry. The economies and the living standards of both developed and developing countries depend to varying degrees upon the efficacy of their chemical industries. Con sequently, this century has seen a wide exploration and expansion of catalytic chemistry together with an intensive investigation of specific, essential processes like those contributing to life-supporting agricultures. Prime among the latter must surely be the "fixation" of atmospheric nitrogen by catalytic hydrogenation to anhydrous ammonia, still the preferred synthetic precursor of the nitrogenous components of fertilizers. In each decade contemporary concepts and techniques have been used to further the understanding, as yet incomplete, of the catalyst, the adsorbates, the surface reactions, and the technology of large-scale operation. The contributors to the present volume review the state of the art, the science, and the technology; they reveal existing lacunae, and suggest ways forward. Around the turn of the century, Sabatier's school was extending the descriptive catalytic chemistry of hydrogenation by metals to include almost all types of multiple bond. The triple bond of dinitrogen, which continued to be more resistant than the somewhat similar bonds in carbon monoxide and ethyne, defied their efforts.

The physical properties of water and steam have been the subject of lhorough investigation for a long time. It can, on the one hand, be due to the important role of this substance in the processes that take place in nature and, on the .other hand, due to its wide industrial use. Steam is the most important working substance used in conventional and nuc lear power plants, in chemical engineering and other fields of industry. The variety of practical use of water and steam generates a need for knowing their thermodynamic, transport, electrical, and other properties over a .very wide range of temperatures and pressures. International Conferences on the Properties of Steam, which have taken place since 1929, have the aim to promote wide exchange of the results of theoretical and experimental studies into the properties of ordinary and heavy water in a11 phase states. In the course of last decade f.he investigation oC physical and chemical properties of concentrated and dilute aqueous solutions that are of interest in the first place from the point of view of power play an important part in these studies."

Lead-based paint has become a national issue and will continue to be a hi- priority focus ofnational, state, and local agencies until there is no lead-based paint in the United States. Lead-based paint has become a tremendous health hazard for people and animals. Lead-based paint has been in widespread use throughout Europe and the United States. Lead has been known to be a health hazard since the time ofPliny the Elder (A. D. 23-79), but it was deemed that the advantages of lead in paint outweighed the health hazards. There has been a change in outlook, and in 1973 the U. S. Congress banned all lead paint from residential structures. A voluminous number of law suits have been initiated since, and continue to be litigated with the purpose of determining the parties responsible for the lead poisoning of children and others and to exact the indemnities. Lead-based paint is still authorized for use on bridges and nonresidential structures, and thousands of city, state, military, and federal government housing projects still contain lead-based paint. This paint must be removed if these dwellings are to be safe living quarters, especially for children. Aba- ment techniques continue to be evaluated; some have been used successfully. Lead-based paint abatement will continue into the next century, and it is hoped that this comprehensive volume will serve as a guide for those seriously interested in this important subject.

aiThis book starts with depiction of the phosphorus role in life creation and evolution. Then it outlines in which vital processes different phosphates participate in life of all flora and fauna, from DNA molecules till body tissues. Crucial function of phosphates was noticed long ago, but only in XIX century discovery of mineral fertilizers made it possible to sustain the needs of growing global population, thus initiating a green revolution. Though, for many decades after it, the complexity of interactions fertilizer-soil-plant roots was underrated, causing massive damages, such as soil destruction and eutrophication of waters. Still, mining of exhausting natural phosphate reserves continued worldwide. Lessons of what happened in XIX century due to scarcity of phosphates were ignored. In the meantime, production of phosphates reached its peak few years ago. Immediate implementation of phosphate recycling technologies from municipal wastes can help avoid imminent global disaster.ai

Metal-Oxygen Clusters is the first book, providing an overview of the surface chemistry and catalytic properties of heteropoly oxometalates. After a brief look at the early knowledge of heteropoly oxometalates, the book discusses the synthesis, characterization, structure, bulk properties and stability of these materials. The remainder and the largest portion of the book explores the properties of these solids as catalysts in acid-catalyzed and oxidation processes in supported or unsupported forms. The book provides an up-to-date review of the methods for synthesizing heteropoly oxometalates of Keggin structure, techniques from spectroscopic through electrochemical to elemental analysis for their characterization and the current information on their structure, bulk properties and their stabilities at high temperatures and under acid and alkaline conditions. The book discusses the materials employed as supports for the title solid and the results of the examination of the supported materials. Methods for the identification of the nature and source of the two catalytic functions, the acidic and oxidative properties, of the heteropoly oxometalates are reviewed and discussed. The use of both the supported and unsupported heteropoly oxometalates as catalysts in acidity-requisite processes ranging from methanol conversion to hydrocarbons to ring-expansion and contraction processes and in oxidation processes from methane cyclohexane are described and related to the aforementioned properties.

To the biochemist, water is, of course, the only solvent worthy of consideration, because natural macromolecules exhibit their remarkable conformational properties only in aqueous media. Probably because of these remarkable properties, biochemists do not tend to regard proteins, nucleotides and polysaccharides as polymers in the way that real polymer scientists regard methyl methacrylate and polyethylene. The laws of polymer statistics hardly apply to native biopolymers. Between these two powerful camps, lies the No-man's land of water soluble synthetic polymers: here, we must also include natural polymers which have been chemically modified. The scientific literature of these compounds is characterized by a large number of patents, which is usually a sign of little basic understanding, of 'know-how' rather than of 'know-why'. Many of the physical properties of such aqueous solutions are intriguing: the polymer may be completely miscible with water, and yet water is a 'poor' solvent, in terms of polymer parlance. ~kiny of the polymers form thermorever sible gels on heating or cooling. The phenomena of exothermic mixing and salting-in are common features of such systems: neither can be fully explained by the available theories. Finally, the eccentric behaviour of polyelectrolytes is well documented. Despite the lack of a sound physico-chemical foundation there is a general awareness of the importance of water soluble vinyl, acrylic, polyether, starch and cellulose derivatives, as witnessed again by ~he vast patent literature.

The purpose of this volume is to present the latest planetary studies of an international body of scientists concerned with the physical and chemical aspects of terrestrial planets. In recent years planetary science has developed in leaps and bounds. This is a result of the application of a broad range of scientific disciplines, particularly physical and chemical, to an understanding of the information received from manned and unmanned space exploration. The first five chapters expound on many of the past and recent observations in an attempt to develop meaningful physical-chemical models of planetary formation and evolution. For any discussion of the chemical processes in the solar nebula, it is important to understand the boundary conditions of the physical variables. In Chapter 1, Saf ranov and Vitjazev have laid down explicitly all the physical constraints and the problems of time-dependence of nebular evolutionary processes. Planetary scientists and students will find in this chapter a collection of astrophysical parameters on the transfer of angular momentum, formation of the disk and the gas envelope, nebular turbulence, physical mixing of particles of various origins and growth of planetesimals. The authors conclude their work with important information on ev olution of terrestrial planets. Although symbols are defined in the text of the article, readers who are not familiar with the many symbols and abbreviations in astrophysical literature will find it useful to consult the Appendix for explanations."

The field of transition metal catalysis has experienced incredible growth during the past decade. The reasons for this are obvious when one considers the world's energy problems and the need for new and less energy demanding syntheses of important chemicals. Heterogeneous catalysis has played a major industrial role; however, such reactions are generally not selective and are exceedingly difficult to study. Homogeneous catalysis suffers from on-site engineering difficulties; however, such reactions usually provide the desired selectivity. For example, Monsanto's synthesis of optically-active amino acids employs a chiral homogeneous rhodium diphosphine catalyst. Industrial uses of homogeneous catalyst systems are increasing. It is not by accident that many homogeneous catalysts contain tertiary phosphine ligands. These ligands possess the correct steric and electronic properties that are necessary for catalytic reactivity and selectivity. This point will be emphasized throughout the book. Thus the stage is set for a comprehensive be treatment of the many ways in which phosphine catalyst systems can designed, synthesized, and studied."

The aim of this compilation has been to provide a comprehensive, non-criti cal source of information concerning organometallic compounds. The scope is limited to the compounds containing at least one carbon-metal bond. The in formation includes methods of preparation, properties, chemical reactions, and applications. The First Edition comprised the literature from 1937 to 1958. The Second Edition is completely revised and extended through 1964. The literature prior to 1937 was thoroughly covered by E. Krause and A. von Grosse in I~ie Chemie der meta11-organischen Verbindungen, " Verlag von Gebrueder Borntraeger, Berlin, 1937. Our work consists of three volumes. Volume I contains derivatives of the transition metals of Groups III through VIII of the Periodic Table. Volume II contains derivatives of germanium, tin, and lead. Volume III contains derivatives of arsenic, antimony, and bismuth. The compilation is based on searches through Chemical Abstracts. The col lection of references for 1964 was completed before the Subject Indexes to Volumes 60 and 61 of the Abstracts were available; thus some omissions in the coverage of that year are possible. We have attempted to make the coverage of the literature complete in order that the compilation may have best utility to the chemist, chemical engineer, patent attorney, and editor. In the interest of brevity, certain numerical data are omitted, but references to the original literature are given. Yield data are rounded to two significant figures. Wherever possible, tables have been used. The entries in the Bibliography section include references to Chemical Abstracts.

The commercial availability and decreasing cost of polyhedral oligomeric silsesquioxanes in recent years has opened up the field to everybody who wishes to apply these unique properties in their own technologies. This is the first book to provide a comprehensive overview of these applications, and covers the synthesis, characterization and history of polyhedral oligomeric silsesquioxanes, their use as metallasilsesquioxane catalysts, their effect upon polymer properties and plastics performance, and their use in superhydrophobic nanocomposites, and electronics, energy, space and biomedical applications.

"Applications of Polyhedral Oligomeric Silsesquioxanes" is a valuable reference for those working across a range of disciplines, including chemists, materials scientists, polymer physicists, plastics engineers, surface scientists, and anybody with a commercial or academic interest in plastics, composite materials, space materials, dental materials, tissue engineering, drug delivery, lithography, fuel cells, batteries, lubricants, or liquid crystal, LED, sensor, photovoltaic or biomedical devices.

In the decade since the introduction of the first commercial lithium-ion battery research and development on virtually every aspect of the chemistry and engineering of these systems has proceeded at unprecedented levels. This book is a snapshot of the state-of-the-art and where the work is going in the near future. The book is intended not only for researchers, but also for engineers and users of lithium-ion batteries which are found in virtually every type of portable electronic product.

I. G OLOGY OF CALCIUM CARBO ATE 1 by Jacques Geyssant 1. Features and characteristics of calcium carbonate 2 1. 1 Calcium carbonate - a special compound 2 1. 2 The crystal forms of calcium carbonate - mineralogy 9 2. The limestones - development and classification 15 2. 1 Sedimentation 16 2. 2 Diagenesis - from sediment to rock 23 2. 3 Classification of the limestones 24 2. 4 Metamorphism - from limestone to marble 26 2. 5 Carbonatites - extraordinary limestones 29 3. Limestone deposits 31 3. 1 Recognition of limestones 31 3. 2 Distribution on the Earth's surface 33 3. 3 Limestone deposits in the geological ages 36 3. 4 CaC0 cycle 42 3 3. 5 Industrially exploitable CaC0 deposits 3 44 53 II. TH C LT RAt HI TORY F LIME TONE by Johannes Rohleder 1. The history of chalk 55 2. Marble and limestone 69 2. 1 Quarrying stones 70 2. 2 Transport, organisation and trade 80 2. 3 The uses 97 137 III. CALCI M CARBOl\ATE - A MODER RESOURCE 1. The beginnings: Calcium carbonate in glazing putty and rubber 138 by Johannes Rohleder 1. 1 A chalk industry is born 139 1. 2 Rubber and glazing putty 142 1. 3 From chalk to calcium carbonate 156 2. Calcium carbonate - pigment and filler 160 by Eberhard Huwald 2. 1 Properties and effects of a filler 164 2. 2 Chalk, limestone, marble, pec - common features and differences 165 2. 2.