This book is devoted to a nontraditional class of materials which are manufactured by the melt-blowing process. The text examines the structure and main properties of melt-blown materials as conditioned by peculiarities of overheated polymer melt spraying in oxidizing medium. Information is given about filtering mechanisms and the main types of polymer fibrous filtering materials.

Composite materials are increasingly used in many applications because they offer the engineer a range of advantages over traditional materials. They are often used in situations where a specified level of performance is required, but where the cost of testing the materials under the extremes of those specifications is very high. In order to solve this problem, engineers are turning to computer Modelling to evaluate the materials under the range of conditions they are likely to encounter. Many of these analyses are carried out in isolation, and yet the evaluation of a range of composites can be carried out using the same basic principles. In this new book the editor has brought together an international panel of authors, each of whom is working on the analysis and Modelling of composite materials. The overage of the book is deliberately wide; to illustrate that similar principles and methods can be used to model and evaluate a wide range of materials. It is also hoped that, by bringing together this range of topics, the insight gained in the study of one composite can be recognized and utilized in the study of others. Professional engineers involved in the specification and testing of composite material structures will find this book an invaluable resource in the course of their work. It will also be of interest to those industrial and academic engineers involved in the design, development, manufacture and applications of composite materials.

The Microsystems Series has as its goal the creation of an outstanding set of textbooks, references, and monographs on subjects that span the broad field of microsystems. Exceptional PhD dissertations provide a good starting point for such a series, because, unlike monographs by more senior authors, which must compete with other professional duties for attention, the dissertation becomes the sole focus of the author until it is completed. Conversion to book form is then a streamlined process, with final editing and book production completed within a few months. Thus we are able to bring important and timely material into book form at a pace which tracks this rapidly developing field. Our first four books in the series were drawn from the more physics-oriented side of the microsystems field, including such diverse subjects as computer-aided design, atomic-force microscopy, and ultrasonic motion detection. Now, with Sangeeta Bhatia's work, we enter the realm of biology. Her use of artifically structured substrates to encourage the liver cells to form orderly assemblies is a fine example of how microfabrication technology can contribute to cell biology and medicine. I am pleased to be able to add this very new and very interesting work to the Microsystems Series. Stephen D. Senturia Cambridge MA Microfabrication in Tissue Engineering and Bioartificial Organs Foreword One of the emerging applications of microsystems technology in biology and medicine is in the field of tissue engineering and artificial organs. In order to function, cells need to receive proper signals from their environment.

Conventional materials, such as nickel based alloys, will not be able to match the required performance specifications for the future generation of high temperature materials. This book reviews the characteristics and potential of a wide range of candidate superalloy replacements, such as ceramics, intermetallics, and their composites. Particular attention is devoted to the problems of processing and design with these materials.

The Eighth Rochester Conference on Coherence and Quantum Optics was held on the campus of the University of Rochester during the period June 13-16,2001. This volume contains the proceedings of the meeting. The meeting was preceded by an affiliated conference, the International Conference on Quantum Information, with some overlapping sessions on June 13. The proceedings of the affiliated conference will be published separately by the Optical Society of America. A few papers that were presented in common plenary sessions of the two conferences will be published in both proceedings volumes. More than 268 scientists from 28 countries participated in the week long discussions and presentations. This Conference differed from the previous seven in the CQO series in several ways, the most important of which was the absence of Leonard Mandel. Professor Mandel died a few months before the conference. A special memorial symposium in his honor was held at the end of the conference. The presentations from that symposium are included in this proceedings volume. An innovation, that we believe made an important contribution to the conference, was the inclusion of a series of invited lectures chaired by CQO founder Emil Wolf, reviewing the history of the fields of coherence and quantum optics before about 1970. These were given by three prominent participants in the development of the field, C. Cohen-Tannoudji, 1. F. Clauser, and R. I. Glauber.

The Sixth International Conference on Sintering and Related Phenomena took place at the University of Notre Dame, Notre Dame, Indiana June 6-8, 1983. This conference was also the twentieth Conference on Ceramic Sciences organized yearly by a "confederation" of four institutions: North Carolina University at Raleigh, N.C., the University of California at Berkeley, CA, Alfred University at Alfred, NY and the University of Notre Dame, Notre Dame, IN. The papers presented at the last Notre Dame conference collect ed in this volume, reflect the progress in our understanding of the process of sintering achieved in the past four years. It seems that the analysis of the two particle models is finally extended to the analysis of the models of compacts. In these investigations strong emphasis is put on pore-grain boundar ies interaction which appear to be central to this problem. It is to be hoped that in the near future an adequate model of the compact will be developed which may serve as a useful basis of powder tech nology. Also, the effects of atmosphere on the sintering of ceramics after a long period of neglect, seem to attract the attention of more workers in the field."

This edition of Thermodynamics is a thoroughly revised, streamlined, and cor rected version of the book of the same title, first published in 1975. It is intended for students, practicing engineers, and specialists in materials sciences, metallur gical engineering, chemical engineering, chemistry, electrochemistry, and related fields. The present edition contains many additional numerical examples and prob lems. Greater emphasis is put on the application of thermodynamics to chemical, materials, and metallurgical problems. The SI system has been used through out the textbook. In addition, a floppy disk for chemical equilibrium calculations is enclosed inside the back cover. It contains the data for the elements, oxides, halides, sulfides, and other inorganic compounds. The subject material presented in chapters III to XIV formed the basis of a thermodynamics course offered by one of the authors (R.G. Reddy) for the last 14 years at the University of Nevada, Reno. The subject matter in this book is based on a minimum number of laws, axioms, and postulates. This procedure avoids unnecessary repetitions, often encountered in books based on historical sequence of development in thermodynamics. For example, the Clapeyron equation, the van't Hoff equation, and the Nernst distribution law all refer to the Gibbs energy changes of relevant processes, and they need not be presented as radically different relationships.

This volume contains the proceedings of the conference on "Atomic and Nanometer Scale Modification of Materials: Fundamentals and Applications" which was co-sponsored by NATO and the Engineering Foundation, and took place in Ventura, California in August 1992. The goal of the organizers was to bring together and facilitate the exchange of information and ideas between researchers involved in the development of techniques for nanometer-scale modification and manipulation. theorists investigating the fundamental mech anisms of the processes involved in modification, and scientists studying the properties and applications of nanostructures. About seventy scientists from all over the world participated in the conference. It has been more than 30 years since Richard Feynman wrote his prophetic article: ''There is Plenty of Room at the Bottom" (Science and Engineering, 23, 22, 1960). In it he predicted that some day we should be able to store bits of information in structures composed of only 100 atoms or so, and thus be able to write all the information accumulated in all the books in the world in a cube of material one two-hundredths of an inch high. He went on to say, "the prin ciples of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom. " Since that time there has been significant progress towards the realization of Feynman's dreams."

These volumes, 9 and 10, of Fracture Mechanics of Ceramics constitute the proceedings of an international symposium on the fracture mechanics of ceramic materials held at the Japan Fine Ceramics Center, Nagoya, Japan on July 15, 16, 17, 1991. These proceedings constitute the fifth pair of volumes of a continuing series of conferences. Volumes 1 and 2 were from the 1973 symposium, volumes 3 and 4 from a 1977 symposium, and volumes 5 and 6 from a 1981 symposium all of which were held at The Pennsylvania State University. Volumes 7 and 8 are from the 1985 symposium which was held at the Virginia Polytechnic Institute and State University. The theme ofthis conference, as for the previous four, focused on the mechanical behavior ofceramic materials in terms of the characteristics of cracks, particularly the roles which they assume in the fracture processes and mechanisms. The 82 contributed papers by over 150 authors and co-authors represent the current state of that field. They address many of the theoretical and practical problems ofinterest to those scientists and engineers concerned with brittle fracture.

Theoretical and experimental work on solids with low-dimensi onal cooperative phenomena has been rather explosively expanded in the last few years, and it seems to be quite fashionable to con tribute to this field, especially to the problem of one-dimensional metals. On the whole, one could divide the huge amount of recent investigations into two parts although there is much overlap bet ween these regimes, namely investigations on magnetic exchange interactions constrained to mainly one or two dimensions and, secondly, work done on Id metallic solids or linear chain compounds with Id delocalized electrons. There is, of course, overlap from one extreme case to the other with these solids and in some rare cases both phenomena are studied on one and the same crystal. In fact, however, most of the scientific groups in this area could be associated roughly with one of these categories and, in addition, a separation between theoreticians and experimentalists in each of these groups leads to a further splitting of interests although many theories about these solids have been tested by experimenta lists. Nevertheless, more cooperation and understanding between scientists working on low-dimensional cooperative phenomena should appreciably stimulate further development. With a better inderdis ciplinary understanding, new ideas could possibly help chemists in synthesizing tailor-cut solids. This would in return give experi mentalists new phenomena to examine and finally would stimulate new theoretical work."

Building on the extensive coverage of the first volume, Volume 2 focuses on the fundamentals of measurements and computational techniques that will aid researchers in the construction and use of measurement devices.

Approximately half of the world production of the petrochemical industry (more than 100 million tonnes) is in the form of polymers, yet it would probably surprise most people to learn how much their lifestyle depends on polymers ranging, as they do, from detergents, kitchenware and electrical appliances to furnishings and a myriad other domestic goods. Still less are they likely to be aware of the extensive part they play in engineering applications for mechanical machine components and advanced high performance aircraft. This versatility derives from the fact that polymeric materials are made up of a range of molecules of varying length, whose properties are related to molecular structure and the proportions of the chains in the mixture. For example, polypropylene is a commodity polymer which is produced in hun dreds of different grades to meet specific market requirements. This depends on the catalyst as well as the operating conditions and reactor design. A major area for growth is in substituting polymers for conventional materials such as ceramics and metals. Not only can they match these materials in terms of mechanical strength and robustness but they have very good resistance to chemical attack. Polyamides, for example, are widely used for car bumpers and new polymers are being developed for engine manifolds and covers. In 1993 there is, typically, 100 kg of various polymers used in cars and this is continually increasing, giving a net weight reduction and hence better fuel economy."

Summary of the recent progress in ceramics research. Several novel concepts for materials selection and microstructural design are presented, as are experimental results that substantiate the ideas.

It is almost self-evident that surface and interface science, coupled with the electronic structure of bulk materials, playa fundamental role in the understanding of materials properties. If one is to have any hope of understanding such properties as catalysis, microelectronic devices and contacts, wear, lubrication, resistance to corrosion, ductility, creep, intragranular fracture, toughness and strength of steels, adhesion of protective oxide scales, and the mechanical properties of ceramics, one must address a rather complex problem involving a number of fundamental parameters: the atomic and electronic structure, the energy and chemistry of surface and interface regions, diffusion along and across interfaces, and the response of an interface to stress. The intense need to gain an understanding of the properties of surfaces and interfaces is amply attested to by the large number of conferences and workshops held on surface and interface science. Because of this need, the fields of surface and interface science have been established in their own right, although their development presently lags behind that of general materials science associated with bulk, translationally invariant systems. There are good reasons to expect this situation to change rather dramatically in the next few years. Existing techniques for investigating surfaces and interfaces have reached maturity and are increasingly being applied to systems of practical relevance. New techniques are still being created, which drastically widen the scope of applicability of surface and interface studies. On the experimental side, new microscopies are bearing fruit.

This volume presents a theoretical and numerical investigation of high index-contrast passive components that can serve as building blocks at the end-points and nodes of WDM communications systems. It presents novel devices for filtering, optical interconnections and coupling to fibres.

The microanalytical technique of atom probe tomography (APT) permits the spatial coordinates and elemental identities of the individual atoms within a small volume to be determined with near atomic resolution. Therefore, atom probe tomography provides a technique for acquiring atomic resolution three dimensional images of the solute distribution within the microstructures of materials. This monograph is designed to provide researchers and students the necessary information to plan and experimentally conduct an atom probe tomography experiment. The techniques required to visualize and to analyze the resulting three-dimensional data are also described. The monograph is organized into chapters each covering a specific aspect of the technique. The development of this powerful microanalytical technique from the origins offield ion microscopy in 1951, through the first three-dimensional atom probe prototype built in 1986 to today's commercial state-of-the-art three dimensional atom probe is documented in chapter 1. A general introduction to atom probe tomography is also presented in chapter 1. The various methods to fabricate suitable needle-shaped specimens are presented in chapter 2. The procedure to form field ion images of the needle-shaped specimen is described in chapter 3. In addition, the appearance of microstructural features and the information that may be estimated from field ion microscopy are summarized. A brief account of the theoretical basis for processes of field ionization and field evaporation is also included.

Silicon, as an electronic substrate, has sparked a technological revolution that has allowed the realization of very large scale integration (VLSI) of circuits on a chip. These 6 fingernail-sized chips currently carry more than 10 components, consume low power, cost a few dollars, and are capable of performing data processing, numerical computations, and signal conditioning tasks at gigabit-per-second rates. Silicon, as a mechanical substrate, promises to spark another technological revolution that will allow computer chips to come with the eyes, ears, and even hands needed for closed-loop control systems. The silicon VLSI process technology which has been perfected over three decades can now be extended towards the production of novel structures such as epitaxially grown optoelectronic GaAs devices, buried layers for three dimensional integration, micromechanical mechanisms, integrated photonic circuits, and artificial neural networks. This book begins by addressing the processing of electronic and optoelectronic devices produced by using lattice mismatched epitaxial GaAs films on Si. Two viable technologies are considered. In one, silicon is used as a passive substrate in order to take advantage of its favorable properties over bulk GaAs; in the other, GaAs and Si are combined on the same chip in order to develop IC configurations with improved performance and increased levels of integration. The relationships between device operation and substrate quality are discussed in light of potential electronic and optoelectronic applications.

Engineering tasks are supposed to achieve defined goals under certain project constraints. Example goals of software engineering tasks include achieving a certain functionality together with some level of reliability or performance. Example constraints of software engineering tasks include budget and time limitations or experience limitations of the developers at hand. Planning of an engineering project requires the selection of techniques, methods and tools suited to achieve stated goals under given project constraints. This assumes sufficient knowledge regarding the process-product relationships (or effects) of candidate techniques, methods and tools. Planning of software projects suffers greatly from lack of knowledge regarding the process-product relationships of candidate techniques, methods and tools. Especially in the area of testing a project planner is confronted with an abundance of testing techniques, but very little knowledge regarding their effects under varying project conditions. This book offers a novel approach to addressing this problem: First, based on a comprehensive initial characterization scheme (see chapter 7) an overview of existing testing techniques and their effects under varying conditions is provided to guide the selection of testing approaches. Second, the optimisation of this knowledge base is suggested based on experience from experts, real projects and scientific experiments (chapters 8, 9, and 10). This book is of equal interest to practitioners, researchers and students. Practitioners interested in identifying ways to organize their company-specific knowledge about testing could start with the schema provided in this book, and optimise it further by applying similar strategies as offered in chapters 8 and 9.

This monograph, which is the outcome of the ASI on High Pressure Chemistry, Biochemistry, and Materials Science, illustrates new developments in the field of high pressure science. In fact, for chemists, biochemists, and materials scientists, pressure as an experimental variable represents a tool which provides unique information about systems of materials studied. It is interesting to note how the growth of the high pressure field is also reflected in the content of the recent ASI's dealing with this field. The ASI High Pressure Chemistry held in 1977 was followed by the ASI High Pressure Chemistry and Biochemistry held in 1986, and the coverage of the present ASI also includes applications to materials science. In view of the teaching character of the ASI, it is natural that main contributions to this volume present overviews of the different subfields or applications of high pressure research. In contrast, contributed papers offer more specialized aspects of various high pressure studies. The various contributions to this volume make clear the impressive range of fundamental and applied problems that can be studied by high pressure techniques, and also point towards a major growth of high pressure science and technology in the near future. This ASI focused mainly on advances achieved in the six years since the previous ASI devoted to the high pressure field. The organization of this volume is as follows.

In recent years remarkable progress has been made in the development of materials for ultrasonic transducers. There is a continuing trend towards increasingly higher frequency ranges for the application of ultrasonic trans ducers in modern technology. The progress in this area has been especially rapid and articles and papers on the subject are scattered over numerous technical and scientific journals in this country and abroad. Although good books have appeared on ultrasonics in general and ultrasonic transducers in particular in which, for obvious reasons, materials play an important part, no comprehensive treatise is available that represents the state-of-the-art on modern ultrasonic transducer materials. This book intends to fill a need for a thorough review of the subject. Not all materials are covered of which, theoretically, ultrasonic trans ducers could be made but those that are or may be of technical impor tance and which have inherent electro acoustic transducer properties, i.e., materials that are either magnetostrictive, electrostrictive, or piezoelectric. The book has been devided into three parts which somewhat reflect the historic development of ultrasonic transducer materials for important tech nical application. Chapter 1 deals with magnetostrictive materials, magnetostrictive met als and their alloys, and magnetostrictive ferrites (polycrystalline ceramics). The metals are useful especially in cases where ruggednes of the transducers are of overriding importance and in the lower ultrasonic frequency range."

Polymer composites represent materials of great and of continuously growing importance. Their potential for application appears to be limitless. They have been the subject of numerous studies both at academic and industrial levels. Much progress has been made in the incisive formulation of composites; sophisticated methods of property evaluation have been developed in the past decade and many, largely empirical solutions have been proposed to resolve the problem of their long-term performance under typical conditions of use (i. e. the use of silane or titane coupling agents to enhance adhesion within composite materials). Assuredly one of the most essential factors in the performance of these systems is the condition of the interface and interphase among the constituents of a given system. It has become clear that it is the interface/interphase, and the interactions which take place in this part of a system, which determine to a significant degree the initial properties of the material. In order to achieve leadership in the formulation and application of polymer composites, it is evident that in depth understanding of interfacial and interphase phenomena becomes a prerequisite.

This book is intended to fill a gap between the theoretical studies and the practical experience of the processor in the extrusion of thermoplastic polymers. The former have provided a basis for numerical design of extruders and their components, but generally give scant attention to the practical performance, especially to the conflict between production rate and product quality. In practice extruders are frequently purchased to perform a range of duties; even so, the operator may have to use a machine designed for another purpose and not necessarily suitable for the polymer, process or product in hand. The operator's experience enables him to make good product in unpromising circumstances, but a large number of variables and interactions often give apparently contradictory results. The hope is that this book will provide a logical background, based on both theory and experience, which will help the industrial processor to obtain the best performance from his equipment, to recognize its limitations, and to face new problems with confidence. Mathematics is used only to the extent that it clarifies effects which cannot easily be expressed in words; ifit is passed over, at least a qualitative understanding should remain. The approximate theory will not satisfy the purist, but this seems to the authors less important than a clear representation of the physical mechanisms on which so much of the polymer processing industry depends. M. J. STEVENS J. A.

Lo, soul! seest thou not God's purpose from the first? The earth to be spann'd, connected by net-work From Passage to India! Walt Whitman, "Leaves of Grass", 1900. The Internet is growing at a tremendous rate today. New services, such as telephony and multimedia, are being added to the pure data-delivery framework of yesterday. Such high demands on capacity could lead to a "bandwidth-crunch" at the core wide-area network resulting in degra dation of service quality. Fortunately, technological innovations have emerged which can provide relief to the end-user to overcome the In ternet's well-known delay and bandwidth limitations. At the physical layer, a major overhaul of existing networks has been envisaged from electronic media (such as twisted-pair and cable) to optical fibers - in the wide area, in the metropolitan area, and even in the local area set tings. In order to exploit the immense bandwidth potential of the optical fiber, interesting multiplexing techniques have been developed over the years. Wavelength division multiplexing (WDM) is such a promising tech nique in which multiple channels are operated along a single fiber si multaneously, each on a different wavelength. These channels can be independently modulated to accommodate dissimilar bit rates and data formats, if so desired. Thus, WDM carves up the huge bandwidth of an optical fiber into channels whose bandwidths (1-10 Gbps) are compati ble with peak electronic processing speed.

This 6th International Symposium on Thermal Expansion, the first outside the USA, was held on August 29-31, 1977 at the Gull Harbour Resort on Hecla Island, Manitoba, Canada. Symposium Chairman was Ian D. Peggs, Atomic Energy of Canada Limited, and our continuing sponsor was CINDAS/Purdue University. We made considerable efforts to broaden the base this year to include more users of expansion data but with little success. We were successful, however, in establishing a session on liquids, an area which is receiving more attention as a logical extension to the high-speed thermophysical property measurements on materials at temperatures close to their melting points. The Symposium had good international representation but the overall attendance was, disappointingly, relatively low. Neverthe less, this enhanced the informal atmosphere throughout the meeting with a resultant frank exchange of information and ideas which all attendees appreciated. A totally new item this year was the presentation of a bursary to assist an outstanding research student to attend the Symposium. We were delighted to welcome Mr. Benedick Fraass from the Univer sity of Illinois to the Symposium, and he responded by making an informal presentation on the topic of his research. We hope this feature will continue. Previous Symposia in the series were: DATE SPONSOR LOCATION CHAIRMEN September 18-20 Gaithersburg, R.K. Kirby Natl. Bureau of 1968 Maryland Standards P.S. Gaal Westinghouse Astronuclear Lab. June 10-12 Santa Fe, R.O. Simmons Materials Res. Lab."