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Streaming potential measurements have been carried out on NUCLEPORE polycarbonate membranes with pore diameters between 0.015 and l.Opm, equilibrated in KC1 or NaCl solutions. Three types of membrane behavior can be seen from the variation of emf with time. Concentration polarization across the membrane is significant for a membrane with pore diameter of 0.015pm. For membranes with pore diameters between 0.015 and 0.6pm, the emf rises rapidly towards a stable value when a pressure difference is applied. In membranes with pore diameters between 0.6 and 1 pm, the high liquid velocity alters the interactions at the wall during the course of measurement, and this is reflected in a decreasing emf with time. Some results obtained by varying pore radius and concentration agree with previous studies. Our results, as well as results reported in the literature, are interpreted in terms of a new theoreti- cal method; the electric work method. Electric work is produced for positive liquid velocity, consistent with momentum production at the membrane wall during the measurement. A relation between the magnitude of layer where momentum transfer takes place and the streaming potential can be applied. Momentum transfer at the membrane wall may extend about 0.1 pm into the pore.

A new treatment of thermoelectric effects in electronic conductors is proposed. The treatment uses only the first and second laws of thermodynamics together with certain laws of local energy and heat production. It is shown how Thomson's relations can be derived without further assumptions, i.e., Onsager reciprocal relations. A simple thermodynamic analogue of the system is presented to emphasize essential points.

23 Na nuclear magnetic relaxation rates in aqueous solutions of NaClO 4 , NaI, and NaBr and of NaBr dissolved in HMPT have been measured as a function of the salt concentration down to concentrations c ⪅ 10 −2 m. In the same way the relaxation rates of 7 LiBr and 87 RbX, X = Cl, Br, I, in aqueous solution have been studied with the effort to reach solute concentrations as small as possible. All the ionic nuclei in question here relax by electric quadrupole interaction and it has been shown that the relaxation rates are proportional to √ c at small concentrations.

The proton magnetic relaxation rate of DMSO in the mixture 33.3 mole % DMSO + 66.7 mole % CD3COOD has been measured in the temperature range 3.5 < 1000/T < 6.0 K and at six frequencies 6 < ν < 144 MHz. The intramolecular relaxation rate was determined by the aid of the isotopic substitution technique. The rotational correlation time of “the molecule” and the time constant of the internal motion have been extracted from these experimental results. The corresponding measurements were also performed on DMSO in the solvent CD3OD (71 mole %) where no internal motion effect appeared in the temperature dependence of the relaxation rate. Furthermore, proton relaxation rates of the acetic acid methyl group and deuteron relaxation rates of the acid methyl and OD group are reported. Again, the data are given in the temperature range as above and for a number of frequencies. Rotational time correlation functions g(t) for the axid molecule are derived. Finally we present experimental results for the self-diffusion coefficients of both mixture partners DMSO and AcH and of DMSO in the solvent MeOH.

A general expression for the EMF of a thermocell has been developed. The equation is based on two principles: delocalized mass and energy conservation in the electric circuit. The development differs from other presentations in two respects: coupled flux equations and Onsager relations are not used to bring out the characteristics of the thermocell. Only well-defined measurable quantities are used. It is shown that the common expressions based on entropies of the constituents and entropies of transport are contained in the new expression. A thermocell is an electrochemical cell in which the temperature is not uniform. Such cells have been treated in the literature within the framework of irreversible thermodynamics in the last 30 years. In this context, it has been generally stated that thermoelectric effects such as the Peltier and Seebeck effects are related, because Onsager's reciprocal relations are valid (1-5). The objective of this paper is to demonstrate that the first and second law of thermodynamics together with some fundamental laws of local mass and energy production, connected with the electrical current, and with simple phenomenological laws for diffusion and heat conduction give a sufficient and necessary basis for a theory of thermocells. As a consequence, it will be shown that Onsager relations are not necessary for a description of thermoelectric effects. In fact generality may be lost by linking these effects only to the validity of Onsager relations. The method of analsyis is based on the two basic features of all electric circuits: energy and mass conservation. Along the closed circuit, there must be a delocalized energy conservation and mass conservation. Momentum conservation may be included when necessary. This starting point was stressed by Hertz (6) in his analysis of isothermal system. It leads, for isothermal system, to an analysis of the local Gibbs energy change s along the circuit, and th e equivalent electric work done in the potentiometer. This analysis has also been emphasized by FSrland et al. (-7). The central concepts in the treatments are the externally controlled electric current and quantities which describe the energy and mass transformations caused by the current. The results obtained in this manner will not depend on quantities which are not well-defined thermodynamically, such as single-ion chemical potentials, single-ion entropies, or local electric fields. The present method of analysis emphasizes changes in each local part of the cell. This makes a distinction of the causes of EMF very clear. The causes have been a matter of discussion in the literature (8). The only assumption intro: duced in the treatment will be those included in linear expansions of variables. This can easily be corrected for, when big temperature differences call for it, and when experimental data are available. Thus we claim that there are no serious limitations given to the method of analysis, i.e., it is in principle general. Because the method focuses on the balancing in various parts of the system of energy and entropy by electric work during an infinitesimal process, we have chosen to name it "the electric work method for analyzing electrochemical cells," in short "the electric work method." The method should be easy to use in electrochemical engineering, because so few basic principles are involved.

The first part of the article deals with the structure of the solvation shell of simple ions, particularly those with the inert gas structure, in aqueous and non-aqueous solution. It is nowadays possible in favorable cases, to determine the solvation number or the coordination number in the first sphere. The solvation shells appear to be “more liquid” than was formerly believed. The hydration of neutral inert particles in aqueous solution is discussed in the second part. Caution is advised in the postulation of particular structural arrangements in the solution.

Durch kernmagnetische Resonanzmessungen sowie durch Untersuchung des chemischen Verhaltens wird gezeigt, das die bisher als Dithiepinthione bzw. Dithiepinone aufgefasten Disulfide der fur III a im Kristallzustand von S. Bezzi vorgeschlagenen Struktur allgemein entsprechen, das aber eine Meribicyclo-Mesomerie nur bei den Verbindungen III, nicht aber bei den Typen IV vorliegt.

We now turn to the class of simpler galvanic cells which are built up of only three constituents. Thus we may have two different cationic constituents and only one anionic constituent. As a first example, we choose the NaCl + KCl system. The galvanic cell with an electrolyte containing two different anionic species and only one cationic constituent should be treated in an analogous way.

The paper is introduced by an analysis of the interrelation between the nuclear magnetic relaxation rates of the cations and anions in the same solution when the nuclear quadrupole interaction is the relaxation mechanism. The treatment is based on an electrostatic model. Higher ion-ion and ion-water correlations may cause mutual quenching or reinforcement of the relaxation effect at higher ion concentrations. Experimental results for the relaxation rates of Rb85, Rb87, Cs133, Li7, and Na23 in the ionic state are reported Most of the solutions are alkali halide solutions, partly the results regard mixed electrolyte solutions. An interpretation of the results in terms of higher ion-ion and ion-water correlations is discussed. A brief consideration of possible “electronic” contributions to the relaxation is also given. Die Arbeit wird eingeleitet durch eine Darlegung der Verknupfung zwischen den kernmagnetischen Relaxationsraten der Kationen und Anionen in derselben Losung, wenn die Kernquadrupol-Wechselwirkung den Reiaxationsmechanismus darstellt. Dieser Untersuchung liegt ein elektrostatisches Modell zugrunde. Hohere Ion-Ion- und Ion-Wasser-Korrelationen konnen bei groserer lonenkonzentration gegen-seitige Ausloschung oder Verstarkung des Relaxationseffektes verursachen. Es werden experimentelle Resultate fur die Relaxationsraten von Rb85, Rb87, Cs133, Li7 und Na23 im ionischen Zustand mitgeteilt. Die meisten der Losungen sind solche von Alkali-Halogeniden, teilweise betreffen die Resultate auch gemischte Elektrolytlosungen. Die Interpretation der Resultate auf Grund von hoheren Ion-Ion-Korrelationen wird diskutiert. Schlieslich wird eine kurze Erorterung uber mogliche “elektronische” Beitrage zum Relaxationsprozes gegeben.