Topics in Applied Chemistry – serie

New laser technology has developed a new dye chemistry! Development of the gallium-arsenic semiconductor laser (diode laser) that emits laser light at 780-830 nm has made possible development of new opto-electronic systems including laser optical recording systems, thermal writing display systems, laser printing systems, and so on. Medical applications of lasers in photodynamic therapy for the treatment of cancer were also developed. In such systems, the infrared absorbing dyes OR dyes) are currently used as effective photoreceivers for diode lasers, and will become the key materials in high technology. At the present time the chemistry of IR dyes is the most important and interesting field in dye chemistry. Laser light can be highly monochromatic, very well collimated, coher­ ent, and, in some cases, extremely powerful. These characteristics make diode lasers a very cheap, convenient, and useful light source for a variety of applications in science and technology. For these purposes, however, IR dyes with special characteristics are required. To develop new IR dyes, it is most important to establish the correlation between the chemical structures of dyes and other characteristics of dyes, such as their absorption spectra. Molecular design of IR dyes predicting the Amax and Emax values by molecular orbital (MO) calculations is now possible even by using a personal computer, and many types of new IR dyes have been demonstrated. Also, new opto-electronic systems using IR dyes as photoreceivers have been reported recently.

Typical examples include liquid crystal dyes, laser dyes, electro­ chromic dyes, dyes for solar cells, dyes for micro color filters, and dyes for nonlinear optical applications.

The application of enzymes or whole cells (fermentatively active or resting; microbial, plant, or animal) to carry out selective transformations of commercial importance is the central theme of industrial biocatalysis. Traditionally, biocatalysis has been in the domain of the life scientist or biochemical engineer. However, recent advances in this field have enabled biocatalytic processes to compete head on with, and in some cases out­ perform, conventional chemical processing. Chemo-biocatalytic systems are being developed thereby combining the most attractive features of bio­ catalysts, namely high specificity, with those of chemical catalysts, such as high reactivities and wide substrate specificities. Hence, synthetic chemists and chemical engineers are now beginning to use biocatalysts as highly selective reagents in chemical synthesis and processing. This book is about biocatalysts and their past, present, and potential applications in the food, pharmaceutical, and chemical industries. The con­ cept of the book did not emanate from a meeting. Rather, it is a compila­ tion of selected examples where biocatalysis either has already made a significant impact in the aforementioned industries, or has the potential to make a substantial contribution. I have been fortunate to have assembled contributions from world-class researchers in the field of biocatalysis. Their timely contributions are sincerely appreciated.

The development of chemicals to selectively control the growth of weeds has been a fascinating success story which has unfolded largely during the last four decades. The dramatic growth of herbicide research that followed the wartime discoveries of the auxin-type herbicides (phenoxyalkanoic acids) resulted in a whole range of compounds and mixtures which are used to eliminate broad-or narrow-leaved weeds from agricultural, horticul­ tural, or forestry crops. Today, the safe use of this armament of compounds requires our understanding of their mode of action, metabolism, and environmental persistence. The most recently developed herbicides are highly effective inhibitors of specific enzyme systems, and formulation may be an important factor determining their efficient delivery at specific target sites. In this book, the major target sites of herbicide action are discussed in Chapters 1-5, with particular reference to photosynthesis; amino acid, lipid, and carotenoid synthesis; and other primary target sites. The effects of synergists or antagonists as modifiers of herbicide action are described in Chapter 6. The importance of efficient target site delivery as a fundamental factor in herbicide activity and selectivity is generally recognized. Delivery of a potentially lethal dose of active ingredient may depend on a whole range of factors including the efficiency of application, retention, absorption, translocation, immobilization, and detoxification. These aspects are con­ sidered in the remaining chapters, with particular reference to the pathways and mechanisms involved in the uptake, translocation, and metabolism of soil-and foliage-applied herbicides.

Striking a balance between the scientific and technological aspects of radiation curing, this work includes both a summary of current knowledge as well as many chapters which present the first comprehensive accounts of their subjects.

The idea for this book came from discussions among participants in a symposium on biotechnical applications at the "Pacifichem 89" meeting in Honolulu. It was the majority opinion of this group that a volume dedicated to biotechnical and biomedical applications of PEG chemistry would enhance research and development in this area. Though the book was conceived at the Honolulu meeting, it is not a proceedings of this symposium. Several groups who did not participate in this meeting are repre­ sented in the book, and the book incorporates much work done after the meeting. The book does not include contributions in all related areas to which PEG chemistry has been applied. Several invited researchers declined to parti.:ipate, and there is not enough space in this single volume to properly cover all submissions. Chapter I-an overview of the topic-discusses in brief applications not given detailed coverage in specifically devoted chapters. The following topics are covered: introduction to and fundamental properties of PEG and derivatives in Chapters 1-3; separations using aqueous polymer two-phase partitioning in Chapters 4-6; PEG-proteins as catalysts in biotechnical applications in Chapters 7 and 8; biomedical applications of PEG-proteins in Chapters 9-13; PEG­ modified surfaces for a variety of biomedical and biotechnical applications in Chapters 14-20; and synthesis of new PEG derivatives in Chapters 21 and 22.

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.

During the past fifteen years commercial interest in compounds containing carbon­ fluorine bonds has burgeoned beyond all expectations, mainly owing to business opportunities arising from work on biologically active fluoroorganics-particularly agrochemicals, the relentless search for new markets for fluoropolymers and fluoro­ carbon fluids, developments in the field of medical diagnostics, and the drive to find replacements for ozone-depleting CFCs and Halon fire-extinguishing agents. Judging the situation to warrant the publication of a comprehensive collection of up-to-date reviews dealing with commercial organofluorine compounds within a single volume of manageable size (and hence reasonable cost), we were delighted to be invited by Plenum Publishing Corporation to produce a suitable book. In order to provide an authentic and wide-ranging account of current commercial applications of fluoroorganic materials, it clearly was necessary to assemble a sizeable team of knowledgeable contributing authors selected almost entirely from industry. Through their efforts we have been able to produce an almost complete coverage of the modem organofluorochemicals business in a manner designed to attract a reader­ ship ranging from experts in the field, through chemists and technologists currently unaware of the extent of industrial involvement with fluoroorganics, to students of applied chemistry. Promised chapters dedicated to perfluoroolefin oxides and 18F labeling of radiopharmaceuticals failed to materialize. This is somewhat unfortunate in view of our aim to achieve comprehensive coverage of the subject.

The chemistry, manufacture, and uses of the specialty chemical resorcinol (1,3-dihy­ droxybenzene) have a rich history, variety, and current interest. This book is intended to be the first detailed review of this product. The numerous references and the Index given in the book are intended to help users of resorcinol and resorcinol derivatives in their work, perhaps even to help in the development of new ideas. The chemical industry in the United States, as well as in many other parts of the world, is being challenged on many fronts, old and new, due to global competitive, environmental, governmental, political, and technological trends that seem more variable than ever before. The case of resorcinol mirrors this array of challenges and demonstrates the broad range of successes and some of the problems of the industry. It is shown how a sprout of a chemical grew over time into a sizable, still growing item of co~erce. In the description of this development it becomes apparent how many different talents and trades it takes to develop, manufacture, and market a product. Also given are indications of how academic research and applied research/devel­ opment quite often, intentionally or not, influence each other and can spur the creative process to the benefit of both. Areas are outlined where the current, often intense, work employing resorcinol is aimed. Thus, the old chemical is shown to be involved in an intriguing tomorrow.

Phosphate Fibers is a singular detailed account of the discovery, chemistry, synthesis, properties, manufacture, toxicology, and uses of calcium and sodium calcium polyphosphate fibers. Author Edward J. Griffith-the inventor and developer of this safe, biodegradable material-takes a multidisciplinary approach to this subject, considering the social, legal, medical, and industrial issues surrounding the use of asbestos and other mineral fibers. This compelling study is a beneficial resource to both readers interested in mineral fibers as well as those who want to understand the complexities of bringing new substances into the modern marketplace.

Contributions by scientists working in international laboratories provide the novice researcher with synthetic data and high-technology applications of leuco dyes. Covering leuco dye classes that exhibit reasonable stability, the book discusses photochromic materials that have wide-ranging applications in memory technology, leuco dyes for color photography, and a special class of dyes formulated by reduction instead of the oxidation process.

Even high-speed supercomputers cannot easily convert traditional two-dimensional databases from chemical topology into the three-dimensional ones demanded by today's chemists, particularly those working in drug design. This fascinating volume resolves this problem by positing mathematical and topological models which greatly expand the capabilities of chemical graph theory. The authors examine QSAR and molecular similarity studies, the relationship between the sequence of amino acids and the less familiar secondary and tertiary protein structures, and new topological methods.

This book is designed for the chemist, formulator, student, teacher, forensic scientist, or others who wish to investigate the composition of polymeric materials. Theinformationwithinthesepagesisintendedtoarmthereaderwiththenecessary workingknowledgetoanalyze,characterize, anddeformulatematerials. ThestructureoftheContentsisintendedtoassistthereaderinquicklylocating the subject of interest and proceed to it with a minimum of expended time and effort. The Contents provides an outline of major topics and relevant materials char- terizedforthereader'sconvenience. Anintroductiontoanalysisanddeformulation is provided in Chapter 1 to acquaint the reader with analytical methods and their applications. Extensive references are provided as additional sources ofinfor- tion. All tables arelocatedin theAppendix, beginning onp. 235. GUIDE FOR USE This is a practical book structured to efficiently use the reader's time with a minimum effort of searching for entries and information by following these brief instructions: 1. Searchthe Contents and/orIndex fora subject withinthe text. 2.Analysis/deformulation principles are discussed at the outset to familiarize the reader with analysis methods and instruments; followed by formu- tions, materials, and analysis ofpaint, plastics, adhesives, and inks; and finally reformulation methods to test the results of analysis. 3. Materials and a wide assortment of formulations are discussed within the text by chapter/section number. 4. Materials are referred toby various names (trivial, trade, and scientific), and these are listed in tables and cross-referenced to aid the reader.

Experiments showing a rapid and reversible change of color seem to be magic and are always fascinating. This process called photochromism, has a few real and many potential applications. Photochromic glasses that darken in the sunlight (protecting eyes from excessive light intensity) and bleach in dim light are today a part of everyday life. Organic Photochromic Compounds in plastic ophthalmic lenses, more comfortable to wear, are now competing with silver salts glasses, despite the longer lifetime of the inorganic system. This successful commercial application has given a new impetus to research in the general field of photochromism that had its most recent revival in the early eighties. The story of organic photochromism with its ups and downs, from the breakthroughs of the pioneering period in the fifties, through the hard times due to the drawbacks of photodegradation and the recent successes is in many ways a saga. The upsurges in the domain were marked by an increasing flow of articles in scientific journals and the publication of several Books (in 1971, 1990 and 1992) which have collected the important accumulated knowledge. Over this period, a considerable number of patents have been issued. International meetings have accompanied this activity, the most recent being held in 1993 (ISOP 93 at Les Embiez Island, France) and in 1996 (ISOP 96 in Clearwater, Florida, USA). Remarkably, these meetings had a good representation from both academia and industry. The next ISOP is planned for 1999 in Fukuoka, Japan.

Experiments showinga rapid and reversible change ofcolor s eem likemagic and are always fascinating. The process involved, photochromism, has a few real and many potential applications. Photochromic glasses thatdarken int he s unlight (protecting eyes from excessive light intensity) and bleach ind im lighta re today a part ofe v eryday life. Organic photochromic compounds in plastic ophthalmic lenses, more comfortable to wear, are now competing with silversalts in glasses, despite the longer lifetime oft he inorganic system. This successful commercial application has given a new impetus to research in the general field of photo chromism, which had its most recent revival in the early eighties. The storyo forganic photochromism with its ups anddowns, from the breakthroughs oft he pioneering periodi n the fifties, through the hardtimes dueto the drawbacks of photodegradation, tot he recent successes is in many ways a saga. The upsurges in this domain were marked by an increasing flow of articles in scientific journals andt he publication of several books (in 1971, 1990, and 1992) that have collectedt he important accumulatedknowledge.Over this period, a considerable number ofpatents have been issued. International meetings have accompanied this activity, the most recent being held in 1993 (ISOP 93 atLes Embiez Island, France) and in 1996 (ISOP 96 inClearwater, Florida). Remark ably, these meetings had good representation from both academia and industry. The next ISOP is planned for 1999 in Fukuoka, Japan.

The fluorine atom, by virtue of its electronegativity, size, and bond strength with carbon, can be used to create compounds with remarkable properties. Small molecules containing fluorine have many positive impacts on everyday life of which blood substitutes, pharmaceuticals, and surface modifiers are only a few examples. Fluoropolymers, too, while traditionally associated with extreme hi- performance applications have found their way into our homes, our clothing, and even our language. A recent American president was often likened to the tribology of PTFE. Since the serendipitous discovery of Teflon at the Dupont Jackson Laboratory in 1938, fluoropolymers have grown steadily in technological and marketplace importance. New synthetic fluorine chemistry, new processes, and new apprec- tion of the mechanisms by which fluorine imparts exceptional properties all contribute to accelerating growth in fluoropolymers. There are many stories of harrowing close calls in the fluorine chemistry lab, especially from the early years, and synthetic challenges at times remain daunting. But, fortunately, modern techniques and facilities have enabled significant strides toward taming both the hazards and synthetic uncertainties. In contrast to past environmental problems associated with fluorocarbon refrigerants, the exceptional properties of fluorine in polymers have great environmental value. Some fluoropolymers are enabling green technologies such as hydrogen fuel cells for automobiles and oxygen-selective membranes for cleaner diesel combustion.

The fluorine atom, by virtue of its electronegativity, size, and bond strength with carbon, can be used to create compounds with remarkable properties. Small molecules containing fluorine have many positive impacts on everyday life of which blood substitutes, pharmaceuticals, and surface modifiers are only a few examples. Fluoropolymers, too, while traditionally associated with extreme high performance applications have found their way into our homes, our clothing, and even our language. A recent American president was often likened to the tribology of PTFE. Since the serendipitous discovery of Teflon at the DuPont Jackson Laboratory in 1938, fluoropolymers have grown steadily in technological and marketplace importance. New synthetic fluorine chemistry, new processes, and new apprecia tion of the mechanisms by which fluorine imparts exceptional properties all contribute to accelerating growth in fluoropolymers. There are many stories of harrowing close calls in the fluorine chemistrylab, especially from the early years, and synthetic challenges at times remain daunting. But, fortunately, modem techniques and facilities have enabled significant strides toward taming both the hazards and synthetic uncertainties, In contrast to past environmental problems associated with fluorocarbon refrigerants, the exceptional properties of fluorine in polymers have great environmental value. Some fluoropolymers are enabling green technologies such as hydrogen fuel cells for automobiles and oxygen selective membranes for cleaner diesel combustion.

Electron Paramagnetic Resonance (EPR) spectroscopy - also sometimes termed Electron Spin Resonance spectroscopy - has manifold potential uses in biochemistry and medicine. The paramount importance of EPR spectroscopy applied to biological tissues and fluids is that it identifies the changes in redox processes that contribute to disease. EPR spectroscopy has come a long way from its original use to detect malignant tumors. For example, the development and later refinement of methods of low-temperature registration of biological tissues widened the scope of EPR spectroscopy. Innovations made possible by the introduction of spin labels, probes, and traps made EPR spectroscopy ever more applicable to biochemistry and medicine, to the point where in vivo studies are being carefully considered. This comprehensive book discusses spectra of many tissues and bodily fluids, and the quantitative nature of paramagnetic centers in both normal individuals and patients suffering from a variety of diseases. Special attention is given to the EPR examination of bio-molecules, such as enzymes, polypeptides, vitamins, lipids, hydrocarbons, etc., which play an essential role in human activity. This book will be of great interest to physicians specializing in many different areas. Similarly, biologists, biochemists, biophysicists, and chemists will find this book very useful. It has also been written so that it may be used as a textbook at graduate level.

Emulsification of vegetable oil-based resins was a daunting task when the author began his research, but the subsequent technology spawned a generation of stable emulsions for waterborne coatings based on vegetable oil-based alkyd resins, oils and fatty acids. Autoxidative polymerization of emulsified alkyd resins is an innovative and original contribution to emulsion technology, because conventional emulsion-polymerization is not applicable to alkyd resins. Emulsified alkyd particles are polymerized while dispersed in stable aqueous media—an original and patented innovation. Smooth and fa- drying alkyd coatings are generated from non-polymerized emulsions and air-dried with conventional metal driers, and have met with marketing success. The pre-polymerization innovation for emulsified alkyd particles provides very fast air-drying coatings that have potential markets for interior architectural latex coatings and waterborne pressure-sensitive adhesives and inks. The author demonstrates his knowledge of chemical reaction kinetics by employing a combination of oxygen concentration, internal reactor pressure and other reactor variables to finely control the rate and degree of autoxidative polymerization. He meticulously calculates surfactant chemistry by measuring hydrophile-lipophile balance values, and solubility parameters to emulsify characterized resins. The relationship between hydrophi- lipophile values and solubility parameters is shown in explicit equations. Homogenization equipment used during the course of this research to generate emulsions is shown in detailed drawings together with concise particle size and distribution data. The author reports research spawned internationally by his research in the fields of alkyd-acrylic hybrids, polyester and oil-modifiedurethane resins.

Survey of Industrial Chemistry arose from a need for a basic text dealing with industrial chemistry for use in a one semester, three-credit senior level course taught at the University of Wisconsin-Eau Claire. This edition covers all important areas of the chemical industry, yet it is reasonable that it can be covered in 40 hours of lecture. Also an excellent resource and reference for persons working in the chemical and related industries, it has sections on all important technologies used by these industries: a one-step source to answer most questions on practical, applied chemistry. Young scientists and engineers just entering the workforce will find it especially useful as a readily available handbook to prepare them for a type of chemistry quite different than they have seen in their traditional coursework, whether graduate or undergraduate.

Stability is one of the most important performances required for silver halide photographic materials. In 1935, Dr. E. 1. Birr introduced the concept of the stabilization ofphotographic emulsions for the first time by inventing a most effective stabilizer, 4-oxo-6-methyl-l,3,3a,7-tetraazaindene (TAl). Dr. Birr's monograph Stabilization ofPhotographic Silver Halide Emulsions was published in 1974,and accepted as a reliable reference book by many photographic scientists and engineers. Since then, silver halide photographic materials have been greatly improved and expanded through active and continual development of various kinds of technologies. Especially, extensive efforts have been made to develop photographic materials with high sensitivity and rapid processing, which rely upon the stability ofphotographic emulsions under various conditions. Thus, the concept and technologies of stabilization ofphotographic silver halide materials have been expanded so extensively that many photographic scientists and engineers eagerly want a reliable, new reference book on the stabilization of photographic emulsions. Dr. Gunther Fischer is one of the most experienced and eminent scientists and engineers in the field of the stabilization of photographic materials with expanded concept. He has been involved in research on the stabilization of pho­ tographic emulsions since 1964 when he joined the Technical Scientific Laboratory in the Research and Development Department of the Photo Film Company Agfa Wolfen formerly headed by Dr. Birr, whom he succeeded in that position. I was deeply impressed by his fruitful and elaborate achievements in these fields.

The present monograph is devoted to the chemistry of nitroazoles, one of the most interesting series of heteroaromatic compounds. The azoles hold a special position in the chemistry of heterocycles. Their unique properties and specific biological activity attract much attention of research chemists all over the world. During the last years the interest in the chemistry of nitroazoles has increasing. The nitro derivatives of azoles have found a wide application in various fields of industrial chemistry, agriculture, and medicine. Medical products developed by nitroazoles incluce a- mycin, metronidazole, misonidazole, tinidazole, nitazole, etc. , ionic liquids, hi- energy materials, synthons for nanocompounds, universal bases in peptide nucleic acids, plant growth regulators, and intermediates for organic synthesis. The investigations in the field of energetic compounds have received enormous interest in recent years. Energetic materials on the base nitroazoles - explosives, propellants, and pyrotechnics - are widely used for both civilian and military applications.Nitroazoles, especially polynitroazoles, possess higher heat of for- tion, density, and oxygen balance than their carbocyclic analogs. A number of ongoing research programs worldwide are aimed for the development of new explosives and propellants with higher performance characteristics or enhanced insensitivity to thermal or shock insults and pyrotechnics with reduced smoke. The preparation of nitroazoles demonstrates its great synthetic potential. At the same time, feasibility and availability of the starting molecules make this strategy a p- erful method for high-energy material construction.

The application of enzymes or whole cells (fermentatively active or resting; microbial, plant, or animal) to carry out selective transformations of commercial importance is the central theme of industrial biocatalysis. Traditionally, biocatalysis has been in the domain of the life scientist or biochemical engineer. However, recent advances in this field have enabled biocatalytic processes to compete head on with, and in some cases out­ perform, conventional chemical processing. Chemo-biocatalytic systems are being developed thereby combining the most attractive features of bio­ catalysts, namely high specificity, with those of chemical catalysts, such as high reactivities and wide substrate specificities. Hence, synthetic chemists and chemical engineers are now beginning to use biocatalysts as highly selective reagents in chemical synthesis and processing. This book is about biocatalysts and their past, present, and potential applications in the food, pharmaceutical, and chemical industries. The con­ cept of the book did not emanate from a meeting. Rather, it is a compila­ tion of selected examples where biocatalysis either has already made a significant impact in the aforementioned industries, or has the potential to make a substantial contribution. I have been fortunate to have assembled contributions from world-class researchers in the field of biocatalysis. Their timely contributions are sincerely appreciated.

Experiments showing a rapid and reversible change of color seem to be magic and are always fascinating. This process called photochromism, has a few real and many potential applications. Photochromic glasses that darken in the sunlight (protecting eyes from excessive light intensity) and bleach in dim light are today a part of everyday life. Organic Photochromic Compounds in plastic ophthalmic lenses, more comfortable to wear, are now competing with silver salts glasses, despite the longer lifetime of the inorganic system. This successful commercial application has given a new impetus to research in the general field of photochromism that had its most recent revival in the early eighties. The story of organic photochromism with its ups and downs, from the breakthroughs of the pioneering period in the fifties, through the hard times due to the drawbacks of photodegradation and the recent successes is in many ways a saga. The upsurges in the domain were marked by an increasing flow of articles in scientific journals and the publication of several Books (in 1971, 1990 and 1992) which have collected the important accumulated knowledge. Over this period, a considerable number of patents have been issued. International meetings have accompanied this activity, the most recent being held in 1993 (ISOP 93 at Les Embiez Island, France) and in 1996 (ISOP 96 in Clearwater, Florida, USA). Remarkably, these meetings had a good representation from both academia and industry. The next ISOP is planned for 1999 in Fukuoka, Japan.

In recent years biocompatible polymers for injuries and wounds have seen advances and innovations that have outpaced the growing field's literature. In this book Dr. Jan W. Gooch, a National Research Council Research Associateship Award recipient, reveals how innovative polymer technology can be applied to the common combat and trauma wounds associated with damaged soft tissue and bleeding. The scope of his investigation spans four distinct devices for wounds, liquid and particulate barrier dressings for soft tissue wounds, sutureless tissue adhesives, antibacterial nanoemulsions, one-hand operated and automatic tourniquets for the battlefield.

Chemical reactions which can, on demand, be switched on and off are valuable for industrial applications. In order to make the best use ofthese reactions, it is essential to have them readily available for a research chemist. The chemical literature, in general, has not yet identified or grouped such reactions. However, their existence is relatively abundant. This book is meant as a survey ofthose reactions which have potential utility in industrially useful processes. These reactions are grouped under the title ofchemical release reactions which can be triggered by heat, light, electric current, etc., to release a specific compound from, or change in the physical or chemical properties of, a unimolecular reactant. The book is divided into chapters covering ways to trigger the release of certain chemicals. Each chapter is further divided into sections, each beginning with a brief introduction ofanalogies ofthe discussed reactions and of how they were used in reported industrial processes. This survey is not meant to be absolute or exhaustive but rather to be directive, to be as complete as possible, and to provide food for further thought.

Stability is one of the most important performances required for silver halide photographic materials. In 1935, Dr. E. 1. Birr introduced the concept of the stabilization ofphotographic emulsions for the first time by inventing a most effective stabilizer, 4-oxo-6-methyl-l,3,3a,7-tetraazaindene (TAl). Dr. Birr's monograph Stabilization ofPhotographic Silver Halide Emulsions was published in 1974,and accepted as a reliable reference book by many photographic scientists and engineers. Since then, silver halide photographic materials have been greatly improved and expanded through active and continual development of various kinds of technologies. Especially, extensive efforts have been made to develop photographic materials with high sensitivity and rapid processing, which rely upon the stability ofphotographic emulsions under various conditions. Thus, the concept and technologies of stabilization ofphotographic silver halide materials have been expanded so extensively that many photographic scientists and engineers eagerly want a reliable, new reference book on the stabilization of photographic emulsions. Dr. Gunther Fischer is one of the most experienced and eminent scientists and engineers in the field of the stabilization of photographic materials with expanded concept. He has been involved in research on the stabilization of pho­ tographic emulsions since 1964 when he joined the Technical Scientific Laboratory in the Research and Development Department of the Photo Film Company Agfa Wolfen formerly headed by Dr. Birr, whom he succeeded in that position. I was deeply impressed by his fruitful and elaborate achievements in these fields.

Survey of Industrial Chemistry arose from a need for a basic text dealing with industrial chemistry for use in a one semester, three-credit senior level course taught at the University of Wisconsin-Eau Claire. This edition covers all important areas of the chemical industry, yet it is reasonable that it can be covered in 40 hours of lecture. Also an excellent resource and reference for persons working in the chemical and related industries, it has sections on all important technologies used by these industries: a one-step source to answer most questions on practical, applied chemistry. Young scientists and engineers just entering the workforce will find it especially useful as a readily available handbook to prepare them for a type of chemistry quite different than they have seen in their traditional coursework, whether graduate or undergraduate.

The traditional use of organic colorants is to impart color to a substrate such as textiles, paper, plastics, and leather. However, in the last five years or so organic colorants have become increasingly important in the high­ technology (hi-tech) industries of electronics and particularly reprographics. In some of these reprographics applications the organic colorant is used in its traditional role of imparting color to a substrate, typically paper or plastic. Examples are dyes for ink-jet printing, thermally transferable dyes for thermal transfer printing, and dyes and pigments for colored toners in photocopiers and laser printers. In other applications it is a special effect of an organic colorant that is utilized, not its color. Examples are electrical effects, such as photoconduction and the electrostatic charging of toners, both of which are essential features for the operation of photocopiers and laser printers, and the selective absorption of infrared radiation, which is utilized in optical data storage. In electronic applications the organic colorant is often employed in a device. Typical examples include liquid crystal dyes, laser dyes, electro­ chromic dyes, dyes for solar cells, dyes for micro color filters, and dyes for nonlinear optical applications.