Publications by authors named "Bedrich Smetana"

The rotating Ring Disk Electrode (RRDE), since its introduction in 1959 by Frumkin and Nekrasov, has become indispensable with diverse applications in electrochemistry, catalysis, and material science. The collection efficiency () is an important parameter extracted from the ring and disk currents of the RRDE, providing valuable information about reaction mechanism, kinetics, and pathways. The theoretical prediction of is a challenging task: requiring solution of the complete convective diffusion mass transport equation with complex velocity profiles.

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Machine learning is increasingly integrated into chemistry research by guiding experimental procedures, correlating structure and function, interpreting large experimental datasets, to distill scientific insights that might be challenging with traditional methods. Such applications, however, largely focus on gaining insights via big data and/or big computation, while neglecting the valuable chemical prior knowledge dwelling in chemists' minds. In this paper, we introduce an Electrochemistry-Informed Neural Network (ECINN) by explicitly embedding electrochemistry priors including the Butler-Volmer (BV), Nernst and diffusion equations on the backbone of neural networks for multi-task discovery of electrochemistry parameters.

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Composites consisting of iron aluminide and iron silicide phases were studied in this work. Powders of iron aluminide and iron silicide were prepared by mechanical alloying separately. Subsequently, they were blended in three different proportions and sintered by the SPS method under various conditions.

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This work aims to assess the effect of an oxygen content graded in minimal quantities, on the order of hundreds of ppms, on the determination of surface tension of low-alloy FeCOCr and FeCONi steels in contact with a corundum substrate. Oxygen, as a surface-active element, was segregated at the surface where it interacted with the major components of the alloys, leading to a reduction in surface tension. The sessile drop method was used for wetting tests in the temperature range from steel liquidus temperatures to 1600 °C under nonoxidizing conditions.

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One of the solutions for overheating the interior in the summer without increasing energy consumption is the integration of phase change material (PCM) into interior plasters. However, adding PCM to plasters deteriorates their properties and thus their usability. The aim of this paper is to determine how the microencapsulated PCM affects the mechanical, thermal, and fire properties of plasters and how much PCM can be added to the plaster.

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The wide application of Nd-Fe-B permanent magnets, in addition to rare-earth metal resource constraints, creates the necessity of the development of efficient technologies for recycling sintered Nd-Fe-B permanent magnets. In the present study, a magnet-to-magnet recycling process is considered. As starting materials, magnets of different grades were used, which were processed by hydrogen decrepitation and blending the powder with NdH.

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The possibilities of metallurgical preparation of 40Nb-60Al and 15W-85Al intermetallic compounds (in at.%) by plasma arc melting (PAM) and vacuum induction melting (VIM) were studied. Both methods allow easy preparation of Nb-Al alloys; however, significant evaporation of Al was observed during the melting, which affected the resulting chemical composition.

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Kaolin is most often used as traditional raw material in ceramic industry. The purpose of the study was to obtain understanding of the structural and chemical variability of cordierite ceramics influenced by chemical and mineralogical properties of six raw kaolins taken from different localities when they are applied in ceramics mixtures with vermiculite and sintered up to 1300 °C. The X-ray diffraction and simultaneous thermogravimetric and differential thermal analysis were used to identify and characterize crystalline mineral phases and the course of reactions during the heating.

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