Heat transfer enhancement in single-phase and two-phase flow heat exchangers in important in such industrial applications as power generating plant, process and chemical industry, heating, ventilation, air conditioning and refrigeration systems, and the cooling of electronic equipment. Energy savings are of primary importance in the design of such systems, leading to more efficient, environmentally friendly devices. This book provides invaluable information for such purposes.

The volume presents in-depth scientific coverage of a vast number of superconductor-based applications. Some of these applications are quite mature, e.g. LTS magnets for MRI, while many others are at various stages of maturity. The first three chapters are devoted to understanding of the principles, fabrication and uses of SQUID magnetometers and gradiometers. The next three cover broader aspects of superconducting electronics - digital LTS circuits and passive component applications using HTS materials. The following four chapters go into magnetic applications. Chapter 11 deals with the...

Progress in the development of oxygen ion and mixed conductors is responsible for innovations in gas sensors, fuel cells, oxygen permeation membranes, oxygen pumps and electrolyzers. Commercialization has been impeded by material stability and compatibility issues, high fabrication costs and an inadequate understanding of the interfacial phenomena controlling the operation of the devices. Here, a group of experts cover all the key topical areas, ranging from fundamentals relating to (a) defects, electrochemical and interfacial processes, (b) catalysis, electrocatalysis and gas reforming, to...

Electrical drives lie at the heart of most industrial processes and make a major contribution to the comfort and high quality products we all take for granted. They provide the controller power needed at all levels, from megawatts in cement production to milliwatts in wrist watches. Other examples are legion, from the domestic kitchen to public utilities. The modern electrical drive is a complex item, comprising a controller, a static converter and an electrical motor. Some can be programmed by the user. Some can communicate with other drives. Semiconductor switches have improved,...

During September 10-14, 1984, we held a Research Workshop at the Lake Arrowhead Conference Center, California, bringing togeth- er leaders in the field of electronic spatial sensors for the blind from the psychology, engineering, and rehabilitation areas. Our goal was to engage these groups in discussion with one another about prospects for the future of electronic spatial sensing, in the light of emerging technologies and the increasing sophistica- tion of behavioral research related to this field. The papers in this book give an update on several of the key research traditions in thi s fi e...

The polydiacetylenes are a class of polymers that are attrac ting increasing attention worldwide. There are many reasons for this interest one of the most important being the availability of many polydiacetylenes as macroscopic, high quality, single crystals. This fact was first reported in the pioneering work of Prof. G. Hegner on the solid-state polymerization of disub stituted diacetylenes in the late 1960s. Since then studies of the polymerization process and the properties of monomers and polymers have advanced understanding of solid-state reactivity and the physiCS of...

Known and developed over the past twenty five years, lasers have been experimented in a variety of processes with an uneven success. Apart from fundamental physics experiments in which the various aspects of coherence are systematically exploited, applications in the field of Materials Science have been scattered recently over so many situations that it is apparently difficult today to conceive a comprehensive interpretation of all physical processes encountered. In some domains of research like photochemistry, development has been fast and rather self-supporting. In others, like solid-state...

Marble in Ancient Greece and Rome: Geology, Quarries, Commerce, Artifacts Marble remains the sine qua non raw material of the an cient Greeks and Romans. Beginning in the Bronze Age sculptu re began in marble and throughout classical times the most im portant statues, reliefs, monuments and inscriptions were made of it. Yet, quarry sources changed in time as preferences for different marbles were influenced by local traditions, the pos sibilities of transport, esthetic tastes, and economics. Marble studies and the identification of the provenance of marble can thus reveal much about Greek and...

Supercritical fluids which are neither gas nor liquid, but can be compressed gradually from low to high density, are gaining increasing importance as tunable solvents and reaction media in the chemical process industry. By adjusting the pressure, or more strictly the density, the properties of these fluids are customized and manipulated for the particular process at hand, be it a physical transformation, such as separation or solvation, or a chemical transformation, such as a reaction or reactive extraction. Supercritical fluids, however, differ from both gases and liquids in many respects....

The purpose of this paper is to present a methodology for estimating space-time stochastic properties of local climatic factors reflecting global climate change. Specifically, daily precipitation amount and daily mean temperature are considered and illustrated with application to the state of Nebraska, U. S. A. Furthermore, a drought index with and without global climate change is examined. The magnitude and consequences of regional response to anticipated climatic changes are uncertain (Houghton et al., 1990). Typical questions to be answered are: can time series of hydrological events or...