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Structural and optoelectronic properties of {\alpha}, \{beta}, {\gamma} phases of calcium titanate are studied with the implementation of first-principles quantum-chemical calculations in the framework of DFT. When optimizing the geometry, the GGA approximation was used. The relaxed lattice parameters obtained by us are identical with the experimental analogs. It has been established that the most stable phase of calcium titanate is the orthorhombic syngony, which corresponds to the results of experimental measurements. It is shown that as the transition from the {\alpha}-phase to the {\gamma}-phase proceeds, the lattice constant parameters and the interatomic distance in these systems increase. The optoelectronic properties of these materials have been studied using the Wien2k code. The high-precision TB-mBJ approximation was used to calculate the exchange-correlation effects. An analysis of the electronic properties of these materials showed that all the studied phases of calcium titanate belong to the class of wide-gap semiconductors. The calculated band gaps for the cubic, tetragonal, and orthorhombic CaTiO3 systems are 2.83, 3.07, and 3.26 eV, respectively. According to the analysis of DOS-plots, it was found that the tetragonal phase of calcium titanate is characterized by the highest density of states. Calculations of the optical constants of the systems under study showed that the CaTiO3 cubic system is characterized by an increased absorption capacity and a relatively high photoconductivity. However, for the other two phases of calcium titanate, the calculations gave identical patterns, i.e., the absorption and optical conductivity spectra of the tetragonal and orthorhombic CaTiO3 systems practically coincide., Comment: 13 pages, 5 figures, 4 tables

Industry 4.0 offers opportunities to combine multiple sensor data sources using IoT technologies for better utilization of raw material in production lines. A common belief that data is readily available (the big data phenomenon), is oftentimes challenged by the need to effectively acquire quality data under severe constraints. In this paper we propose a design methodology, using active learning to enhance learning capabilities, for building a model of production outcome using a constrained amount of raw material training data. The proposed methodology extends existing active learning methods to effectively solve regression-based learning problems and may serve settings where data acquisition requires excessive resources in the physical world. We further suggest a set of qualitative measures to analyze learners performance. The proposed methodology is demonstrated using an actual application in the milk industry, where milk is gathered from multiple small milk farms and brought to a dairy production plant to be processed into cottage cheese., Comment: Technical Report for a CIKM'21 paper

The thermoelectric properties of AlMgB14-based materials prepared by spark plasma sintering were investigated. Al, Mg, and B powder were used as raw material powders. The raw powders were mixed using a V-shaped mixer, and then the mixture was sintered at 1673 K or 1773K. The mixture ratio of raw powders was varied around stoichiometric ratio of AlMgB14. X-ray diffraction patterns of samples showed that all samples consist of AlMgB14 and some by-products, MgAl2O4, B2O and AlB12. The Seebeck coefficient of the samples exhibited significant change depending on the varying mixture ratio. One sample exhibited a large negative value for the Seebeck coefficient (approximately -500 {\mu}V/K) over the temperature range from 573K to 1073 K, while others showed positive value (250-450 {\mu}V/K). Thus n-type AlMgB14-based material has been realized simply by varying raw material ratio.

A totally green chemistry alternative that would lead both to energy production from renewable feedstocks and to solutions of parts of ecological problems related to waste disposals would be very attractive. Pyrolysis of used frying oils seems to be one option for this attractive alternative as we propose to demonstrate in this study. Since 2002, the whole production of waste edible oils (around 100 000 tons per year in France) must be collected and transformed into secondary raw material by specific companies. The general aim of the present work is to produce one of the following target sources of energy: (i) H2 for fuel cells, (ii) H2/CO in satisfactory ratios to produce biodiesel by Fischer-Tropsch (FT) reaction, or (iii) hydrocarbon mixtures with high added value. Therefore, in this work, the conversion of a crude used frying oil, named VEGETAMIXOIL^(r); from Ecogras Company (France), was investigated (weight composition: C 73.6%; O 9.7%; H 12.2%). In support of our knowledge related to fatty acids and methyl esters, a laboratory pilot plant was built to study the pyrolysis of used frying oils. Effects of temperature (700-800 degrees C), residence time, addition of reaction initiator (H2O2) or inhibitor (thiophene), and diluent (water or nitrogen) were analysed with regard to the nature and amounts of pyrolysis products. Results led to the conclusion that the best operating conditions of pyrolysis are 800 degrees C with water as diluent, leading to the production of dihydrogen (40%) and hydrocarbons from methane to propylene, essentially. CO and CO2 are also produced but with low molar fractions. Furthermore, a ratio H2/CO favourable for low temperature FT is obtained.

The powdery nature and high alkali content of vegetable ashes make them ideal raw materials to be used as modifiers of silicate compositions (glasses, enamels and ceramics). Their utilisation since ancient times is described in the literature of the history of glasses, but studies on the analyses of their composition are still limited. We discuss here the compositions of tree and shrub ashes (wattle, hawthorn, oak, green oak, olive wood, elm, poplar, apple tree, vine shoot), of plants (carex, fern, dogwood), of cereals (wheat, maize, rice), threshing waste and hay, mainly harvested in Maconnais, near Taiz\'e (Sa\^one-et-Loire, France), by the potter Brother D. de Montmolin. The contributions in alkali modifiers (Na2O, K2O), alkaline-earth (CaO, MgO) and in silica are discussed in view of the data gathered from the literature of the history of techniques used in the production of ceramics, enamels and glasses. The huge variation in composition is usually attributed to recycling and is questioned by the very broad range of compositions that we obtained in the analyses of the ashes.

This report describes statistical characterization of physical properties of the composite material system MTM45-1/CF7442A, which has been tested and is currently being considered for use on spacecraft structures. This composite system is made of 6K plain weave graphite fibers in a highly toughened resin system. This report summarizes the distribution types and statistical details of the tests and the conditions for the experimental data generated. These distributions will be used in multivariate regression analyses to help determine material and design allowables for similar material systems and to establish a procedure for other material systems. Additionally, these distributions will be used in future probabilistic analyses of spacecraft structures. The specific properties that are characterized are the ultimate strength, modulus, and Poisson􀂶s ratio by using a commercially available statistical package. Results are displayed using graphical and semigraphical methods and are included in the accompanying appendixes.