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Rationale: Ceria‐based systems are of great interest because of their unique properties. Such systems may be used as anode materials for SOFCs or in oxygen sensors. The exploitation of these materials often requires high temperatures. In such conditions, the partial or complete evaporation of materials is possible. Therefore, knowledge of the values of partial pressures and thermodynamic properties is essential to predict and/or prevent possible consequences and accidents. Methods: Knudsen effusion mass spectrometry was used to determine partial pressures of vapor species over the SrO–CeO2 and CaO‐CeO2 systems. Measurements of partial pressures were performed with a MS‐1301 mass spectrometer. Vaporization was carried out using molybdenum or tungsten effusion cells. A theoretical study of gaseous strontium and calcium cerates was performed by several quantum chemical methods: density functional theory (DFT) M06, DFT PBE0, and MP2. Results: The minimum value of relative electron ionization cross‐section for CeO2 was estimated. In the temperature range of 2218–2249 K above the SrO‐CeO2 system and of 2128–2208 K above the CaO‐CeO2 system, gaseous M, MO, MO, CeO2, O, O2 and MCeO3 (M = Sr, Ca) were found. Energetically favorable structures of gaseous SrCeO3 and CaCeO3 were found, and vibrational frequencies were evaluated in the "rigid rotor‐harmonic oscillator" approximation. On the basis of the equilibrium constants of gaseous reaction MO + CeO2 = MCeO3, the standard formation enthalpy of gaseous SrCeO3 (−913 ± 26 kJ/mol) and of gaseous CaCeO3 (−917 ± 26 kJ/mol) at 298 K were determined. Conclusions: The estimated value of relative electron ionization cross‐section for CeO2 is in agreement with the general rule applicable for dioxides. The stability of SrCeO3 and CaCeO3 gaseous species was confirmed by KEMS. Gas‐phase reactions involving gaseous SrO (CaO) and CeO2 with gaseous SrCeO3(CaCeO3) were studied. Enthalpy of formation reaction of gaseous SrCeO3(CaCeO3) from gaseous SrO (CaO) were evaluated theoretically, and the obtained value is in agreement with the experimental one. [ABSTRACT FROM AUTHOR]

Due to the expected rise in the world population, an increase in the requirements for quality and safety of food and feed is expected, which leads to the growing demand for new sources of sustainable and renewable protein. Insect protein is gaining importance as a renewable material for several reasons, reflecting its potential contributions to sustainability, resource efficiency, and environmental conservation. Some insect species are known to be able to efficiently convert organic waste into high-value products such as protein, requiring less land and water compared to traditional livestock. In addition, insect farming produces fewer greenhouse gas emissions, contributing to mitigating climate change. Insects are considered as a major potential alternative to animal or plant protein due to their many nutritional benefits, including high protein, mineral, and vitamin contents. On average, the protein content of insects ranges between 35% and 60% dry weight, which exceeds plant protein sources, such as cereal, soybeans, and lentils. As the acceptance of insect protein grows and technologies advance, the food and feed industries continue to explore and expand their applications, offering consumers diverse and sustainable protein choices. In this review, we discuss the recent findings relating to insect protein focusing on its characteristics, extraction methods, applications, and opportunities along with some trade-offs and uncertainties. Graphic Abstract [ABSTRACT FROM AUTHOR]

Development of the advanced materials based on the TiO2‐SiO2‐ZrO2 system is hindered by lack of the information on its thermodynamic properties and phase equilibria. In the present study, the samples in the TiO2‐SiO2‐ZrO2 system were prepared by solid‐state synthesis and analyzed by X‐ray microanalysis, fluorescence, and diffraction techniques. The thermodynamic properties in this system were evaluated by Knudsen effusion mass spectrometric (KEMS) method and optimized within the generalized lattice theory of associated solutions (GLTAS). The main vapor species over the silica‐containing samples vaporized from the tungsten cell at the temperature 1973 K were SiO, O, WO2, and WO3. The vapor over the samples in the TiO2‐ZrO2 system at 2356 K was composed mainly of TiO, TiO2, O, WO2, and WO3. The activity of components in the samples and the partial pressures of the identified vapor species were determined. At 1973 K, the TiO2‐SiO2‐ZrO2 system is characterized by positive deviations from the ideality. The observed weak dependence of the SiO2 activity on the SiO2 content suggests the presence of a broad field of immiscibility on the phase diagram in the concentration range 40–100 mol. % SiO2. The thermodynamic data on the TiO2‐SiO2‐ZrO2 system obtained by KEMS can be of great value for calculation of the phase equilibria. [ABSTRACT FROM AUTHOR]

Rationale: The SrO–Al2O3 system holds promise as a base for a wide spectrum of advanced materials, which may be synthesized or applied at high temperatures. Therefore, studying vaporization and high‐temperature thermodynamic properties of this system is of great practical importance. Methods: Samples of the SrO–Al2O3 system were obtained by solid‐state synthesis and identified by X‐ray fluorescence analysis, X‐ray phase analysis, scanning electron microscopy, electron probe microanalysis, simultaneous thermal analysis, and thermogravimetric analysis. The thermodynamic properties of the SrO–Al2O3 system were studied by the Knudsen effusion mass spectrometric (KEMS) method and were fitted by the Redlich–Kister and Wilson polynomials. The thermodynamic values obtained were also optimized within the generalized lattice theory of associated solutions (GLTAS). Results: The vapor composition, temperature, and concentration dependences of the partial vapor pressures over the samples under study as well as the SrO activities in melts of the SrO–Al2O3 system were determined by the KEMS method. Usage of the Redlich–Kister and Wilson polynomials allowed calculation of the excess Gibbs energies, enthalpies of mixing, and excess entropies in the concentration range 0–33 mol% of SrO at temperatures of 2450 and 2550 K. Conclusions: Significant negative deviations from the ideality were observed in the melts of the SrO–Al2O3 system at 2450, 2550, and 2650 K. The Wilson polynomial was found to be the optimal approach to describe the thermodynamic properties in the system studied. Optimization of the experimental data using the GLTAS approach allowed the characteristic features of the thermodynamic description of the SrO–Al2O3 system to be elucidated and explained. [ABSTRACT FROM AUTHOR]

Rationale: Materials based on the Al2O3‐SiO2‐ZrO2 system are promising for a wide range of high‐temperature technological applications, such as thermal barrier coatings in the aviation and space industry or advanced materials in nuclear power reactors. Experimental studies of the ceramics based on this system by the Knudsen effusion mass spectrometric (KEMS) method are of significant interest in designing technological processes for the synthesis and exploitation of the Al2O3‐SiO2‐ZrO2 materials. Methods: Samples of ceramics in the Al2O3‐SiO2‐ZrO2 system, including the Al2O3‐ZrO2 and SiO2‐ZrO2 binaries, were prepared by solid‐state synthesis. Analysis of the samples was performed by X‐ray fluorescence and diffraction techniques. The vapor composition and thermodynamic properties of the components in this system were determined by KEMS. The derived thermodynamic functions were optimized within the generalized lattice theory of associated solutions (GLTAS). Results: In the temperature range 1900–2600 K, the SiO, Al, AlO, Al2O, ZrO, ZrO2, and O vapor species were identified over the samples in the systems under study. For the thermodynamic properties to be determined correctly, the samples of the Al2O3‐SiO2‐ZrO2 system had to be vaporized at temperatures less than 2000 K, where data could be obtained only for the SiO species. The SiO2 activities obtained were taken as the experimental basis for the modeling within the GLTAS approach. This allowed evaluation of the component activities and excess Gibbs energy, and assessment of the relative number of bonds of different types. Conclusions: At 1920 K, the Al2O3‐SiO2‐ZrO2 system is characterized by negative deviations of its thermodynamic properties from the ideal behavior. The consistency of the obtained modeling results was illustrated by comparison of the values derived from the data for the ternary and the boundary binary systems and thereby indicates the reasonable uniformity of the energy parameters of the lattice model derived in the calculations, which may be used in further modeling of multicomponent systems. [ABSTRACT FROM AUTHOR]

Rationale: The TiO2–Al2O3–SiO2 system is the base for various glass–ceramic materials, which have great practical value for a large number of modern technologies. Many TiO2–Al2O3–SiO2 materials are synthesized or applied at high temperatures, which justifies the relevance of the present study. Methods: The samples in the TiO2–Al2O3–SiO2 system were synthesized using the method of induction melting in a cold crucible. The thermodynamic properties of the TiO2–Al2O3–SiO2 system were studied using the Knudsen effusion mass spectrometric method. The derived thermodynamic functions were optimized within the generalized lattice theory of associated solutions (GLTAS) approach and compared with the results of calculation using the semiempirical Kohler, Muggianu, Toop, Redlich–Kister, and Wilson methods based on the corresponding data in the binary systems. Results: The SiO2 selective vaporization from the samples under study was shown at temperatures above 1940 K. The thermodynamic properties in the TiO2–Al2O3–SiO2 system, including the TiO2–SiO2 system, were obtained in the temperature range 1965–2012 K and were optimized using GLTAS to obtain the consistent concentration dependences of the component activities and excess Gibbs energies. Conclusions: Positive deviations from the ideal behavior were observed in the TiO2–Al2O3–SiO2 system at high temperatures. Comparison of these values with the results of the modeling based on the GLTAS approach allowed the recommendations regarding the optimal semiempirical methods for the excess Gibbs energy calculation in different concentration ranges to be made. [ABSTRACT FROM AUTHOR]

ABSTRACT One of the most important environmental protection problems for coal-fired power plants is prevention of atmospheric pollution of flying ash. The ash particles are typically removed from flue gases [...]

Rationale: Materials based on the Gd2O3‐ZrO2‐HfO2 system are promising for a wide range of high‐temperature technological applications, such as for obtaining thermal barrier coatings in the aviation and space industry, as well as advanced materials in nuclear power applications. Experimental studies of the ceramics based on this system by the Knudsen effusion mass spectrometric method provides such valuable information as the vapor composition over the samples and enables derivation of the thermodynamic functions. Methods: Samples of ceramics in the Gd2O3‐ZrO2‐HfO2 system were synthesized and analyzed by X‐ray fluorescence and diffraction techniques. The vaporization processes and partial pressures of the vapor species over the samples were obtained by the high‐temperature mass spectrometric method using the ion current comparison method. The derived thermodynamic functions were optimized within the Generalized Lattice Theory of Associated Solutions (GLTAS) approach. Results: At the temperature of 2600 K, the GdO, ZrO, ZrO2, HfO, and O vapor species were found over the samples, but only for the GdO and ZrO species were accurate experimental data on the partial pressures obtained. In all the ceramic samples, the Gd2O3 activity was determined. On this experimental basis, modeling within the GLTAS approach was performed. It allowed the evaluation of the Gd2O3, ZrO2, and HfO2 activities in the system under study and a rough approximation of the excess Gibbs energy as a function of composition to be obtained. Conclusions: At 2600 K the Gd2O3‐ZrO2‐HfO2 system is characterized by negative deviations of its thermodynamic properties from the ideal behavior. Consistency of the obtained modeling results indicate reasonable uniformity of the energy parameters of the lattice model derived in calculations of the hafnia‐containing oxide systems, which may be used in further modeling of multicomponent systems. [ABSTRACT FROM AUTHOR]

Rationale: Strontium aluminates can be used as refractory construction materials at temperatures up to 2000°С or as the materials for immobilization of long‐lived radioactive waste. The SrО‐Al2O3 system is one of the more complicated oxide systems used for the creation of new radio‐transparent materials. The exploitation of such materials at high temperatures demands the knowledge of the thermal stability of the compounds and solid solutions formed in the SrО‐Al2O3 system. Methods: The synthesis of the samples in the SrO‐Al2O3 system was carried out by a ceramic method at 1250°C. The characterization of the samples was accomplished with the use of X‐ray diffraction (XRD). The vaporization of the samples under study was performed from a twin tungsten effusion cell using the Knudsen effusion mass spectrometry method. Results: The temperature dependences of partial pressures of vapor species over 4SrO·Al2O3, 3SrO·Al2O3, SrO·Al2O3, SrO·2Al2O3 and SrO·6Al2O3 in a wide range of temperatures were determined. The component activities, the Gibbs energies of mixing and the standard enthalpies of individual strontium aluminates were obtained. Conclusions: The thermodynamic properties of the SrO‐Al2O3 system at high temperatures are characterized by negative deviation from ideality. The vaporization processes and thermodynamic properties of the SrO‐Al2O3 system were obtained for the first time. [ABSTRACT FROM AUTHOR]