On the Issue of the Thermal Emission Cathode Resource on the Oxide Films of Hafnium and Zirconium

The article shows the results of research on the destruction of the thermionic cathode of an arc plasma torch when inserting hafnium and zirconium along the trace of the spot of a gas-discharge arc by means of electronic metallography with spectral analysis in the control region. The depth of penetration of the spot into the metal of the cathode insert was determined due to the discrete mechanism of action on the metal at the time of attachment. The erosion rate of zirconium oxide films was experimentally established, the extension of the operating life substantiated while mechanisms for its increase were revealed, and two types of arc contact with a hafnium or zirconium insert - the "contracted" and "diffused" ones - were offered. The theoretical operating life of the cathode is calculated

Stability and operating life of electrolysis hydrogen-oxygen generators

Translated from Ukrainian (Avtom. Svarka 1999 (5) p. 64-66)Available from British Library Document Supply Centre-DSC:9023.190(VR-Trans--8937)T / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Determination of terms of the stable burning of oxyhydrogen flame

Приведені результати досліджень умов стійкого горіння полум'я з використанням воднево- кисневої суміші отриманої з електролізно-водяних генераторів. Розглянуті питання зміни швидкості витікання струменя при зміні витрати, складу суміші, діаметрів сопел. Встановлені закономірності зміни геометричних параметрів факела і швидкості течії продуктів горіння від складу суміші при зворотному ударі, стійкому горінні і відриві полум'я. The results of research of flame burning conditions using a hydro-oxygen mixture, hydro-oxygen mixture with addition of carbon-hydrogen vapors are given. The results of research were compared to similar parameters of a propane-oxygen mixture. The questions of changing of jet’s velocity are considered, the mixture composition and nozzle diameters being varied. The change of flow length upon the mixture composition relationships are established for backfire, steady burning and separation of flame. The distribution of the jet velocity along the length of torch for three cases of the flow expiration with use of different mixtures and numbers of tips is calculated. The optimal band of steady flame burning is established

How Well Do Student Nurses Write Case Studies? A Cohesion-Centered Textual Complexity Analysis

International audienceStarting from the presumption that writing style is proven to be a reliable predictor of comprehension, this paper investigates the extent to which textual complexity features of nurse students' essays are related to the scores they were given. Thus, forty essays about case studies on infectious diseases written in French language were analyzed using ReaderBench, a multipurpose framework relying on advanced Natural Language Processing techniques which provides a wide range of textual complexity indices. While the linear regression model was significant, a Discriminant Function Analysis was capable of classifying students with an 82.5% accuracy into high and low performing groups. Overall, our statistical analysis highlights essay features centered on document cohesion flow and dialogism that are predictive of teachers' scoring processes. As text complexity strongly influences learners' reading and understanding, our approach can be easily extended in future developments to e-portfolios assessment, in order to provide customized feedback to students