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The direct current‐voltage characteristics of symmetrical cells Pt, O2(I), |Zr0.85Ca0.15O1.85|normalPt , O2(II), with pO2false(Ifalse)=pO2false(IIfalse) , were measured at 560°C under oxygen pressures from 1 to 10−20 atm. The characteristics were nonohmic, the deviation from ohmic law being mainly due to the potential drop at the cathode interface between the solid electrolyte and the gas ambient. The characteristics consist of two parts. The first is characterized by a marked oxygen pressure dependence and is observed at voltages lower than approximately 2V (weak polarization). In this range, the rate‐determining process is the diffusion of oxygen atoms (resulting from dissociation of O2 or H2O ) through the platinum of the Pt paste electrode. The second part of the characteristic is almost independent of the oxygen pressure and is observed at voltages higher than approximately 2V (strong polarization). Here the rate‐determining step is the process in which neutral oxygen atoms, adsorbed at the cathode surface of the electrolyte, combine with effectively neutral oxygen vacancies VOx , (oxygen ion vacancies which have trapped two electrons) to form a normal O2− lattice ion false(OOxfalse) . This process utilizes the part of the electrolyte surface not in contact with the platinum, but close to points where the platinum makes contact, and involves migration of electrons from the platinum over the surface of the electrolyte.

Sense of coherence (SOC) has been proposed as a psychological factor that predicts good health and positive adjustment. The three components of SOC: manageability, comprehensibility and meaning were assessed together with depression, hopelessness and self-esteem as factors predicting future suicidal ideation and behaviour in parasuicides. One hundred and fifty hospitalized parasuicides were evaluated on these measures and followed up after six months to determine their current level of suicidal ideation and whether they had been readmitted for a further attempt or killed themselves in the intervening period. Suicidal ideation on admission was best predicted by a low score on the SOC meaning subscale and also significantly related to the other predictor variables. Suicidal ideation at the six-month follow-up was best predicted by the SOC subscales manageability and comprehensibility. These two SOC subscales also emerged as discriminators of suicidal behaviour over the six months following admission. Overall prediction of suicidal behaviour was enhanced by also including the background variables of age, a history of previous attempts, unemployment and whether the attempter was living alone. The study ends with a discussion of the importance of widening the focus when assessing and predicting suicidal risk to include not only predictions based on pathology but also psychological factors that promote adjustment.

The sintering of zinc oxide powder compacts has been investigated at constant rates of heating of 0.5° to 15°C/min. For samples with the same initial relative density (0.50), the temperature derivative of the densification strain versus density fits within a single, relatively narrow band. At low temperatures the densification rate as a function of temperature increases almost linearly with the heating rate. The data, covering a wide density range of 0.5 to 0.98, are consistent with an analysis that accounts for the coarsening (defined as an increase in the mean pore separation) in terms of two classes of microstructural coarsening processes: those associated with densifying and with nondensifying mechanisms.

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