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Preliminary Notes

Despite the fact that the structure of the interface between a metal and an electrolyte solution has been the subject of numerous experimental and theoretical studies since the early days of physical chemistry, our understanding of this important system is still incomplete. One problem has been the unavailability (until recently) of experimental data that can provide direct structural information at the interface. For example, despite the fact that much is known about the structure of the ion s solvation shell from experimental and theoretical studies in bulk electrolyte solutions, information about the structure of the adsorbed ion solvation shell has been mainly inferred from the measured capacity of the interface. The interface between a metal and an electrolyte solution is also very complex. One needs to consider simultaneously the electronic structure of the metal and the molecular structure of the water and the solvated ions in the inhomogeneous surface region. The availability of more direct experimental information through methods that are sensitive to the microscopic [Pg.116]

For a long period of time, molten salts containing niobium and tantalum were widely used for the production by electrolysis of metals and alloys. This situation initiated intensive investigations into the electrochemical processes that take place in molten fluorides containing dissolved tantalum and niobium in the form of complex fluoride compounds. Well-developed sodium reduction processes currently used are also based on molten salt media. In addition, molten salts are a suitable reagent media for the synthesis of various compounds, in the form of both single crystals and powdered material. The mechanisms of the chemical interactions and the compositions of the compounds depend on the structure of the melt. [Pg.135]

Molten salts are characterized by the formation of discrete complex ions that are subjected to coordination phenomenon. Such complex ions have specific compositions that are related to the rearrangement of their electronic configuration and to the formation of partially covalent bonds. The life time of the coordinated ions is longer than the contact period of the individual ions [293]. [Pg.135]

Molten salt investigation methods can be divided into two classes thermodynamic and kinetic. In some cases, the analysis of melting diagrams and isotherms of physical-chemical properties such as density, surface tension, viscosity and electroconductivity enables the determination of the ionic composition of the melt. Direct investigation of the complex structure is performed using spectral methods [294], [Pg.135]

Investigation of fluoride melts containing tantalum or niobium is a very difficult procedure that involves high temperatures, corrosion activity and the [Pg.135]

Three conceptual steps can be discerned in the definition of the ionic structure of fluoride melts containing tantalum or niobium. Based on the very first thermodynamic calculations and melting diagram analysis, it was initially believed that the coordination numbers of tantalum and niobium, in a molten system containing alkali metal fluorides, increase up to 8. [Pg.136]

The study of the previous chapters may hopefully convince critics that this modern joining process is based on solid production-related, chemical and physical principles that, if carefully observed, guarantee high quality levels. It has to be mentioned, however, that the preconditions for the application of bonding are quite different. There is, on the one hand, [Pg.93]

In the following, we therefore attempt to provide both fields of application with suitable information, since successful and precise bonding is the aim of all users. In addition, adhesive manufacturers have a comprehensive range of information material on adhesive selection and adhesive processing for the products they offer. [Pg.93]

In order to systemize the information important for the selection of the adhesive, the following preliminary notes are helpful  [Pg.93]

Applied Adhesive Bonding A Practical Guide for Flawless Results. Gerd Habenicht Copyright 2009 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 978-3-527-32014-1 [Pg.93]

The information is limited to the most important materials, metals, plastics, (thermoplastics, thermoset materials, foams), ceramics, glass and their possible combinations. For papers, cardboards, wood, rubber polymers, usually physically setting systems (solvent-based, dispersion, hot-melt adhesives) are utilized. In these cases, the adhesive selection with regard to the manufacturing conditions and demands is of less problematic nature. [Pg.94]


Butzer, K.W. 1979a Preliminary notes on the geology of Die Kelders. Annals of the South African Museum 78 225-228. [Pg.112]

Innes JRM, Ulland BM, Valerio MG, et al. 1969. Bioassay of pesticides and industrial chemicals for tumorigenicity in mice A preliminary note. J Natl Cancer Inst 42 1101-1114. [Pg.300]

Published work abstracted covers the period up to the end of 1971. References are not always given to preliminary notes and conference reports when full papers are available. A number of relevant reviews exists (see Table I). [Pg.254]

Hjerten, S. (1958). Free zone electrophoresis Preliminary note. Arkiv for Kemi 11, 151-152. [Pg.361]

Discharge through the latter at Low Pressures. Journal of the Chemical Society Transactions 103 1 (1913) 419-26. [The preliminary note of this article was in Proceedings of the Chemical Society of London 29 410 (February 15, 1913) 22. Part II in Proceedings of the Chemical Society 29 418 (June 28, 1913) 216-21.]... [Pg.238]

Zl. Zetterqvist, H., and Hendrix, T. R., A preliminary note on an ultrastructural abnormality of the intestinal epithelium in adult celiac disease. Bull. Johns Hopkins Hosp. 106, 240-249 (1960). [Pg.121]

Presently, the expansion of winged bean production and commercial development is inhibited by the lack of dwarf morphological variants and ecological uncertainties (80). A preliminary note on the development of bush type mutant in India has appeared (81), though scientific details have not been reported yet. [Pg.217]

Mortensen, J. T J. S. Sorensen, and N. A. Sorensen Studies Related to Naturally Occurring Acetylcn< Compounds. XXXII. A Preliminary Note on a Red. cetylenic Pigment in Eriophyllum caespitosum Dougl. Acta Chem. Scand. 13, 2392 (1964). [Pg.100]

In the middle of the afternoon he returned, very excited. He had completed writing out the preliminary notes for what became "the experiment at La Chorrera." It is the only written record of his ideas that was actually made at the time, and as such, it is the only piece of written, primary evidence that we have about how we viewed what we were doing as we were doing it. [Pg.69]

We interprete the above effects as conventional product shape selectivity inside the pore system of zeolite ZSM-5 or ZSM-11, and part of our arguments were presented earlier, in a preliminary note [28]. While the catalyst is on stream, coke is gradually formed and deposits, in part, inside the channel system. As a consequence, the diffusion pathways for product molecules increase. Slim molecules, such as 2,6-dimethylnaphthalene are less affected than... [Pg.298]

After the apparatus had been perfected, hydrogen was the first gas to be investigated and, although the investigation of this gas has not been completed, it seemed that a preliminary note on the apparatus, together with the results so far obtained, would be of interest to those engaged in ionization potential and allied work. [Pg.1]

Hexamethylphosphoramide was tested for carcinogenicity in rats, the only species tested, by inhalation in this study, which was reported as a preliminary note, it produced squamous-cell carcinomas of the nasal cavity. It has also been inadequately tested in rats by oral administration (lARC, 1977). [Pg.1466]

Sandorfy was struck by the artificial character of this approximation. His first target was the series of normal chain saturated hydrocarbons. A preliminary note on his results was published in the Comptes Rendus de VAcademie des Sciences.6 After taking up his position in Montreal, he greatly extended this work by introducing three different approximations, which he called the C CH, and H approximations.7 The first was based only on the atomic orbitals of the carbons, the second used the hybrid sp3 orbitals of the carbons and the Is orbitals of the hydrogens, and the third included all the valence atomic orbitals of the carbons and the hydrogens. [Pg.217]

We will now give some preliminary notes that will be necessary for the following discussions. [Pg.220]

Conti-Fuhrman, A. and Rabino Massa, E. (1972). Preliminary note on the ultrastructure of the hair from an Egyptian mummy using the scanning electron microscope. /. Human Evol. 1, 487-488. [Pg.142]

In the last 5 years at least eight reviews concerning polynuclear metal carbonyls have been published (16,18, 84, 41, 86, 87, 91, 108), and it may appear unlikely that any new material could be added at this time. Nevertheless, we have willingly accepted the invitation of the Editors to present a comprehensive review which, beside the material published up to June 1974, also summarizes the most relevant of our recent results, as yet only published as preliminary notes. [Pg.285]

In their second communication of 1887, Griess and Harrow3 realized that the reaction of o-phenylenediamine was not so simple as they had assumed in their preliminary note, and that the results differed accord-... [Pg.176]

H. Hase, S. Miyachi and S. Mihara (1963). A preliminary note on the phosphorus compounds in chloroplasts and volutin granules isolated from Chlorelta cells. In H. Tamiya (Ed.), Microalgae and Photosyntetic Bacteria, University of Tokyo Press, Tokyo, Japan, p. 619. [Pg.227]


See other pages where Preliminary Notes is mentioned: [Pg.60]    [Pg.195]    [Pg.135]    [Pg.136]    [Pg.207]    [Pg.38]    [Pg.263]    [Pg.116]    [Pg.19]    [Pg.56]    [Pg.232]    [Pg.58]    [Pg.282]    [Pg.222]    [Pg.60]    [Pg.94]   


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