Gypsum rocks are widely exploited in the world as industrial minerals. The purity of the gypsum rocks (percentage in gypsum mineral in the whole rock) is a critical factor to evaluate the potential exploitability of a gypsum deposit. It is considered than purities higher than 80% in gypsum are required to be economically profitable. Gypsum deposits have been studied with geoelectrical methods; a direct relationship between the electrical resistivity values of the gypsum rocks and its lithological composition has been established, with the presence of lutites being the main controlling factor in the geoelectrical response of the deposit. This phenomenon has been quantified in the present study, by means of a combination of theoretical calculations, laboratory measurements and field data acquisition. Direct modelling has been performed; the data have been inverted to obtain the mean electrical resistivity of the models. The laboratory measurements have been obtained from artificial gypsum-clay mixture pills, and the electrical resistivity has been measured using a simple electrical circuit with direct current power supply. Finally, electrical resistivity tomography data have been acquired in different evaporite Tertiary basins located in North East Spain; the selected gypsum deposits have different gypsum compositions. The geoelectrical response of gypsum rocks has been determined by comparing the resistivity values obtained from theoretical models, laboratory tests and field

Since the discovery and development of adequate superconducting materials, the development of motors has been a challenge for applications. The basis of design, however, has been the substitution of copper wires by superconducting tapes in coils in order to obtain a higher working field, thus improving power density and efficiency.In the case of high-power motors, the benefit is clear. The cost of the materials, cryogenics and building procedures could be assumed by the clear benefit in size, weight, efficiency, and, in some cases, reliability. Otherwise, low-power motors require a different treatment. Superconducting wires are insufficiently developed to produce small coils for a high field with the adequate shape. Air gaps are more critical than in large motors and cost has a major impact. Only very specific applications, in which standard technology cannot give a reliable and satisfactory solution, could benefit from superconductivity. This paper summarizes our work realized by applying superconducting pellets in low-power motors, thus improving their power density, reliability, dynamics and regularity. Applications to cryogenics, control and high speed have been our focus.

Ethanol steam reforming with pure ethanol and commercial bioethanol (S/C = 3) was carried out inside the housing of the exhaust gas pipe of a gasoline internal combustion engine (ICE) by using exhaust heat (610–620 °C). Various catalytic honeycombs loaded with potassium-promoted cobalt hydrotalcite and with ceria-based rhodium–palladium catalysts were tested under different reactant loads. The hydrogen yield obtained over the cobalt-based catalytic honeycomb at low load (F/W < 25 mLliq·gcat-1·h-1, GHSV = 4·102 h-1) was remarkably high, whereas that obtained over the noble metal-based catalytic honeycombs was much superior at high loads (F/W = 25–150 mLliq·gcat-1·h-1, GHSV = 4·102–2.4·103 h-1). At higher reactant loads the overall hydrogen production was limited by heat transfer from the exhaust heat to the reformer inside the housing of the exhaust gas pipe of the ICE. Extensive carbon deposition occurred over the cobalt-based honeycomb, making its use impractical. In contrast, stability runs (>200 h) at high load (F/W = 150 mLliq·gcat-1·h-1, GHSV = 2.4·103 h-1) showed that promotion of the ceria-supported noble metal catalyst with alumina and zirconia is a key element for practical application using commercial bioethanol. HRTEM analysis of post mortem honeycombs loaded with RhPd/Ce0.5Zr0.5O2–Al2O3 showed no carbon formation and no metal agglomeration.Postprint (author's final draft

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