Water and Aqueous Solutions at Subzero Temperatures

Water and Aqueous Solutions at Subzero Temperatures

Author: Felix Franks

Publisher: Springer Science & Business Media

Published: 2013-11-11

Total Pages: 495

ISBN-13: 1475769520

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This Volume, the last of the series, is devoted to water in its metastable forms, especially at sub-zero temperatures. The past few years have wit nessed an increasing interest in supercooled water and amorphous ice. If the properties of liquid water in the normal temperature range are already eccentric, then they become exceedingly so below the normal freezing point, in the metastable temperature range. Water can be supercooled to -39°C without too much effort, and most of its physical properties show a re markable temperature dependence under these conditions. Although ade quate explanations are still lacking, the time has come to review available knowledge. The study of amorphous ice, that is, the solid formed when water vapor is condensed on a very cold surface, is of longer standing. It has achieved renewed interest because it may serve as a model for the liquid state. There is currently a debate whether or not a close structural relation ship exists between amorphous ice and supercooled water. The nucleation and growth of ice in supercooled water and aqueous solutions is also still one of those grey areas of research, although these topics have received considerable attention from chemists and physicists over the past two decades. Even now, the relationships between degree of supercooling, nucleation kinetics, crystal growth kinetics, cooling rate and solute concentration are somewhat obscure. Nevertheless, at the empirical level much progress has been made, because these topics are of considerable importance to biologists, technologists, atmospheric physicists and gla ciologists.


The Physics and Physical Chemistry of Water

The Physics and Physical Chemistry of Water

Author: Felix Franks

Publisher: Springer

Published: 1995-12-31

Total Pages: 596

ISBN-13: 9780306371813

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to arrive at some temporary consensus model or models; and to present reliable physical data pertaining to water under a range of conditions, i.e., "Dorsey revisited," albeit on a less ambitious scale. I should like to acknowledge a debt of gratitude to several of my col leagues, to Prof. D. J. G. Ives and Prof. Robert L. Kay for valuable guidance and active encouragement, to the contributors to this volume for their willing cooperation, and to my wife and daughters for the understanding shown to a husband and father who hid in his study for many an evening. My very special thanks go to Mrs. Joyce Johnson, who did all the cor respondence and much of the arduous editorial work with her usual cheerful efficiency. F. FRANKS Biophysics Division Unilever Research Laboratory ColworthjWelwyn Colworth House, Sharnbrook, Bedford March 1972 Contents Chapter 1 Introduction-Water, the Unique Chemical F. Franks I. lntroduction ........................................ . 2. The Occurrence and Distribution of Water on the Earth 2 3. Water and Life ...................................... 4 4. The Scientific Study of Water-A Short History ........ 8 5. The Place of Water among Liquids . . . . . . . . . . . . . . . 13 . . . . . Chapter 2 The Water Moleeule C. W. Kern and M. Karplus 1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 . . . . . . . . . . 2. Principles of Structure and Spectra: The Born-Oppenheimer Separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 . . . . . . . . . . . . 3. The Electronic Motion ............................... 26 3.1. The Ground Electronic State of Water ............ 31 3.2. The Excited Electronic States of Water ........... 50 4. The Nuclear Motion ................................. 52 5. External-Field Effects ................................. 70 5.1. Perturbed Hartree-Fock Method . . . . . . . . . . . . . . . 74 . . .


Water: A Comprehensive Treatise

Water: A Comprehensive Treatise

Author: Felix Franks

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 466

ISBN-13: 1468480189

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Since the publication of the previous volumes many new aspects of the physical and life sciences have been developed in which the properties of water play a dominant role. Although, according to its preface, Volume 5 was to be the last one of the treatise, these recent developments have led to a revision of that statement. The present volume and its companion, still in preparation, deal with topics that were already mentioned in the preface to Volume 5 as gaining in importance. The recent development of X-ray and, more particularly, neutron scattering techniques have led to studies of "structure" in aqueous solutions of electrolytes on the one hand, and to the role of water in protein structure and function on the other. Both these topics have reached a stage where reviews of the present state of knowledge are useful. The application of ab initio methods to calculations of hydration and conformation of small molecules has a longer history, but here again a critical summary is timely. The role of solvent effects in reaction kinetics and mechanisms should have had a place in Volume 2 of this treatise, but, as sometimes happens, the author who had taken on this task failed tQ live up to his promise. However, since 1972 the physical chemistry of mixed aqueous solvents has made considerable strides, so that the belated discussion of this topic (by a new author) is built on evidence that was not available at the time of publication of Volume 2.


Properties of Water in Foods

Properties of Water in Foods

Author: D. Simatos

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 692

ISBN-13: 9400951035

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Water is recognized as being an important factor in numerous pheno mena connected with the quality of food. For instance, it plays a part in the textural properties of several commodities. Moreover, water is an essential parameter determining the behaviour of food products in the course of many processing operations : on water, will depend the amount of energy necessary for freezing or dehydrating the product; water will strongly influence the evolution of physical, chemical and biochemical phenomena taking place in the product during processing operations such as heating, drying, etc. Water will also influence the same reactions, as well as the activity of microorganisms, during the storage of food products under various conditions. As a result, all aspects of quality - sensory, nutritional and hygienic properties of the food - will be affected. In all these circumstances, the water content of a product is obviously an important factor, but equally important may be the physical properties of this water, such as its thermodynamic activity and its mobility. Actual ly, the concept of water activity (a ) is now widely used by the food industry and in the legislation of sever')¥l countries. The idea of a small, international meeting devoted to a synthetic review and discussion of knowledge on these various matters, was first developed by Dr. R. B.


Texture in Food

Texture in Food

Author: B M McKenna

Publisher: Woodhead Publishing

Published: 2003-07-03

Total Pages: 446

ISBN-13: 9781855736733

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Texture is one of the most important attributes used by consumers to assess food quality. This quality is particularly important for the growing number of semi-solid foods from sauces and dressings to yoghurt, spreads and ice cream. With its distinguished editor and international team of contributors, this authoritative book summarises the wealth of recent research on what influences texture in semi-solid foods and how it can be controlled to maximise product quality. Part one reviews research on the structure of semi-solid foods and its influence on texture, covering emulsion rheology, the behaviour of biopolymers and developments in measurement. Part two considers key aspects of product development and enhancement. It includes chapters on engineering emulsions and gels, and the use of emulsifiers and hydrocolloids. The final part of the book discusses improving the texture of particular products, with chapters on yoghurt, spreads, ice cream, sauces and dressings. With its summary of key research trends and their practical implications in improving product quality, Texture in food Volume 1: semi-solid foods is a standard reference for the food industry. It is complemented by a second volume on the texture of solid foods. Summarises the wealth of recent research on what influences texture in semi-solid foods and how it can be controlled to maximise product quality Reviews research on the structure of semi-solid foods and its influence on texture, covering emulsion rheology, the behaviour of biopolymers and developments in measurement Considers key aspects of product development and enhancement and includes chapters on engineering emulsions and gels and the use of emulsifiers and hydrocolloids