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Journal articles on the topic 'Thermochemical database'

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Published: 3 June 2025

Last updated: 20 July 2025

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Voigt, W., V. Brendler, K. Marsh, et al. "Quality assurance in thermodynamic databases for performance assessment studies in waste disposal." Pure and Applied Chemistry 79, no. 5 (2007): 883–94. http://dx.doi.org/10.1351/pac200779050883.

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Performance assessment studies in underground disposal of radioactive or toxic waste need to consider all reactive interactions between waste and its surroundings. Thermodynamic equilibrium and reaction path calculations represent an important tool for this purpose. The reliability of the results depends first of all on the quality of the thermodynamic database used for the calculations. Several quality criteria of thermodynamic databases are discussed in connection with the characteristics of current database projects [Nuclear Energy Agency Thermochemical Database (NEA-TDB), Yucca Mountain database, Dortmund Databank (DDB), Common Thermodynamic Database (CTD), FreeGS, and Thermodynamic Reference Database (THEREDA)] including the situation for molten salts. The future role of the IUPAC standard for thermophysical and thermochemical data storage is emphasized.

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SHIMURA, Kazuki, and Atsushi ABE. "JICST factual database. (3). JICST thermophysical and thermochemical property database." Journal of Information Processing and Management 31, no. 1 (1988): 41–55. http://dx.doi.org/10.1241/johokanri.31.41.

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Martinez, Jesus S., Eugenio-Felipe Santillan, Manuel Bossant, Davide Costa, and Maria-Eleni Ragoussi. "The new electronic database of the NEA Thermochemical Database Project." Applied Geochemistry 107 (August 2019): 159–70. http://dx.doi.org/10.1016/j.apgeochem.2019.05.007.

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Frandsen, Flemming, Kim Dam-Johansen, and Peter Rasmussen. "GFEDBASE — A pure substance trace element thermochemical database." Calphad 20, no. 2 (1996): 175–229. http://dx.doi.org/10.1016/s0364-5916(96)00025-9.

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Novak, Igor. "Thermochemical Database of Halomethanes, Halosilanes, Halophosphines, and Haloamines." Journal of Chemical Information and Computer Sciences 40, no. 2 (2000): 358–60. http://dx.doi.org/10.1021/ci990040q.

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Sukkaew, Pitsiri, Lars Ojamäe, Örjan Danielsson, Olof Kordina, and Erik Janzén. "Revisiting the Thermochemical Database of Si-C-H System Related to SiC CVD Modeling." Materials Science Forum 778-780 (February 2014): 175–78. http://dx.doi.org/10.4028/www.scientific.net/msf.778-780.175.

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Chemical vapor deposition of silicon carbide (SiC-CVD) is a complex process involving a Si-C-H system wherein a large number of reaction steps occur. To simulate such a system requires knowledge of thermochemical and transport properties of all the species involved in the process. The accuracy of this information consequently becomes a crucial factor toward the correctness of the outcome prediction. The database on thermochemical properties of well-known species such as small hydrocarbons has been established over decades and it is accurate and easily accessible. On the other hand, the database for less frequently used species such as organosilicons is still under development. Apart from the accuracy issue, a consistency in acquiring procedures, whether theoretical or experimental, is another factor controlling the final error of the simulated outcome. In this work, the thermochemical data for several important growth species for SiC CVD using the SiH4/CxHy/H2system has been calculated. For the most part an excellent agreement is seen with previously reported data, however for the organosilicons a larger deviation is detected and in particular for the CH3SiH2SiH species which shows a stark deviation from the CHEMKIN database.

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Haussener, Sophia. "(Invited) Solar Fuel Processing: Performance and Longevity Requirements and Trends." ECS Meeting Abstracts MA2023-02, no. 48 (2023): 2441. http://dx.doi.org/10.1149/ma2023-02482441mtgabs.

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I present the learnings from the Solar Fuels Database (SolarFuelsDB) and the review of the different solar fuels approaches [1] in terms of performance and longevity. The SolarFuelsDB is an open database for experimental demonstrations of solar to fuel devices (photoelectrochemical and solar thermochemical for water splitting and/or CO2 reduction) based on the FAIR principles. The database and the review aim to accelerate the development of such technologies. Utilizing this dataset and the review, I present a comprehensive review of photo-electrochemical and solar thermochemical devices, identify notable trends categorized by device taxonomy, architecture, and materials, and provide a second law analysis in order to identify potential of the various material systems and approaches. References [1] S. Haussener, Solar Energy, 10.1016/j.solener.2022.09.019, 2022.

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Tang, Kai, Eivind J. Øvrelid, Gabriella Tranell, and Merete Tangstad. "A Thermochemical Database for the Solar Cell Silicon Materials." MATERIALS TRANSACTIONS 50, no. 8 (2009): 1978–84. http://dx.doi.org/10.2320/matertrans.m2009110.

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Туманов, Владимир Евгеньевич, and Андрей Иванович Прохоров. "Electronic Database on Experimental Bond Dissociation Energies of Organic Compounds." Russian Digital Libraries Journal 24, no. 6 (2022): 1203–16. http://dx.doi.org/10.26907/1562-5419-2021-24-6-1203-1216.

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The presented web database on experimental homolytic bond dissociation energies in organic compounds is intended for use by a wide range of theoreticians and practitioners in free access. The paper provides a brief overview of the sources of the dissociation energies of bonds of organic molecules, which are calculated theoretically, measured experimentally and estimated from kinetic and thermochemical experimental data, their presentation in the Internet database. A web database on homolytic bond dissociation energies of organic compounds is presented. The reported bond dissociation energies are calculated from experimental kinetic and thermochemical data. Descriptions of experimental data sources, classes of organic compounds and calculation methods are given. The logical structure of the database and the description of the main fields of its tables are given. The main search form of the database interface is presented and an example of a search result for a specific organic compound is given. Bond dissociation energies are calculated at a temperature of 298.15 K, which is usually absent in most sources. The analogs of the present base are inferior to the latter in taking into account temperature correlations. Currently, work is underway to analyze and analyze the published data taking into account the entropy effects.

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Osugi, Jiro, Kyoko Eriguchi, and Kazuki Shimura. "Development of the JICST thermophysical and thermochemical property database system." Netsu Bussei 1, no. 2 (1987): 62–67. http://dx.doi.org/10.2963/jjtp.1.62.

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Novak, Igor. "ChemInform Abstract: Thermochemical Database of Halomethanes, Halosilanes, Halophosphines, and Haloamines." ChemInform 31, no. 25 (2010): no. http://dx.doi.org/10.1002/chin.200025255.

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Besmann, Theodore M., Juliano Schorne-Pinto, Mina Aziziha, et al. "Applications of Thermochemical Modeling in Molten Salt Reactors." Materials 17, no. 2 (2024): 495. http://dx.doi.org/10.3390/ma17020495.

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The extensively evaluated and consistent thermodynamic database, the Molten Salt Thermal Properties Database—Thermochemical (MSTDB-TC), was used along with additional thermodynamic values from other sources as examples of ways to examine molten salt reactor (MSR) fuel behavior. Relative stability with respect to halide potential and temperature for likely fuel and fission product components were mapped in Ellingham diagrams for the chloride and fluoride systems. The Ellingham diagrams provide a rich, visual means for identifying halide-forming components in proposed fuel/solvent salt systems. Thermochemical models and values from MSTDB-TC and ancillary sources were used in global equilibrium calculations to provide compositions for a close analysis of the behavior of a possible Molten Chloride Salt Fast Reactor and a Molten Salt Reactor Experiment-type system at high burnup (100 GWd/t). The results illustrated the oxidative nature of burnup in MSRs and provided information about redox behavior and possible control.

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Class, Caleb A., Jorge Aguilera-Iparraguirre, and William H. Green. "A kinetic and thermochemical database for organic sulfur and oxygen compounds." Physical Chemistry Chemical Physics 17, no. 20 (2015): 13625–39. http://dx.doi.org/10.1039/c4cp05631k.

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Cordfunke, E. H. P., and R. J. M. Konings. "Thermochemical data for reactor materials and fission products: The ECN database." Journal of Phase Equilibria 14, no. 4 (1993): 457–64. http://dx.doi.org/10.1007/bf02671964.

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Perlovich, German, and Artem Surov. "Polymorphism of monotropic forms: relationships between thermochemical and structural characteristics." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 76, no. 1 (2020): 65–75. http://dx.doi.org/10.1107/s2052520619015671.

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In this work, a database containing thermochemical and structural information about 208 monotropic polymorphic forms has been created and analyzed. Most of the identified compounds (77 cases) have been found to have two polymorphs, 14 compounds have three forms and there are only three examples of systems with four polymorphs. The analysis of density distribution within the database has revealed that only 62 out of 114 metastable polymorphs (referred to as group I) obey the `density rule' proposed by Burger and Ramberger [(1979), Mikrochim. Acta, 72, 259–271], while the remaining 45% of the monotropic systems (group II) violate the rule. A number of physicochemical, structural and molecular descriptors have been used to find and highlight the differences between group I and group II of the polymorphs. Group II is characterized (on average) by higher values of descriptors, which are responsible for conformational flexibility of molecules. An algorithm has been proposed for carrying out bivariate statistical analysis. It implies partitioning the database into structurally related clusters based on Tanimoto similarity coefficients and subsequent analysis of each cluster in terms of the number of hydrogen bonds per molecule.

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Li, Liping, Guiyue Du, Beibei Yan, et al. "Carbon Footprint Analysis of Sewage Sludge Thermochemical Conversion Technologies." Sustainability 15, no. 5 (2023): 4170. http://dx.doi.org/10.3390/su15054170.

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Thermochemical conversion technology for sewage sludge (SS) management has obvious advantages compared to traditional technologies, such as considerable volume reduction, effective pathogen elimination, and potential fuel production. However, few researchers conducted comparative research on the greenhouse gas (GHG) emission performances of these technologies. This paper evaluates the lifecycle carbon footprints of three SS thermochemical conversion technologies, including hydrothermal liquefaction (HTL) (Case 1), pyrolysis (Case 2), and incineration (Case 3) with software OpenLCA and Ecoinvent database. The results show that Case 1 has the smallest carbon footprint (172.50 kg CO2eq/t SS), which indicates the HTL process has the best GHG emission reduction potential compared to other SS disposal routes. The biggest contributor to the carbon footprint of SS thermochemical conversion technologies is indirect emissions related to energy consumption. So the energy consumption ratio (ECR) of the three cases is calculated to assess the energy consumption performances. From the perspective of energy conversion, Case 1 shows the best performance with an ECR of 0.34. In addition, element balance analysis is carried out to deeply evaluate the carbon reduction performance of the three cases. This study fills the knowledge gap regarding the carbon footprints for SS thermochemical conversion technologies and provides a reference for future technology selection and policymaking against climate change in the SS management sector.

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Ishida, Toyokazu. "Computational exploration for high density thermal storage materials based on thermochemical/physical database." Journal of the Atomic Energy Society of Japan 65, no. 3 (2023): 174–78. http://dx.doi.org/10.3327/jaesjb.65.3_174.

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Bhosale, Rahul R., Anand Kumar, Fares AlMomani, Majeda Khraisheh, and Gorakshnath Takalkar. "Solar Energy Storage via Thermochemical Metal Oxide/Metal Sulfate Water Splitting Cycle." MRS Advances 3, no. 24 (2018): 1341–46. http://dx.doi.org/10.1557/adv.2018.50.

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ABSTRACTThis paper reports the effect of Ar molar flow-rate on thermodynamic efficiency analysis of zinc oxide-zinc sulfate (ZnS-ZnO) water splitting cycle useful for solar H2 production. The thermodynamic efficiency analysis is conducted using the HSC Chemistry 7.1 software and its thermodynamic database. Influence of Ar molar flow-rate on total solar energy input essential for the continuous operation of the cycle is explored. Furthermore, the solar-to-fuel energy conversion efficiency for the ZnS-ZnO water splitting cycle is determined.

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Kostov, Ana, and Dragana Zivkovic. "Thermodynamic calculations in ternary titanium-aluminium-manganese system." Journal of the Serbian Chemical Society 73, no. 4 (2008): 499–506. http://dx.doi.org/10.2298/jsc0804499k.

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Thermodynamic calculations in the ternary Ti-Al-Mn system are shown in this paper. The thermodynamic calculations were performed using the FactSage thermochemical software and database, with the aim of determining thermodynamic properties, such as activities, coefficient of activities, partial and integral values of the enthalpies and Gibbs energies of mixing and excess energies at two different temperatures: 2000 and 2100 K. Bearing in mind that no experimental data for the Ti-Al-Mn ternary system have been obtained or reported. The obtained results represent a good base for further thermodynamic analysis and may be useful as a comparison with some future critical experimental results and thermodynamic optimization of this system.

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Sato, Yutaka S., Masahiro Muraguchi, and Hiroyuki Kokawa. "Tool Wear and Reactions in 304 Stainless Steel during Friction Stir Welding." Materials Science Forum 675-677 (February 2011): 731–34. http://dx.doi.org/10.4028/www.scientific.net/msf.675-677.731.

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Four kinds of the welding tools made of PCBN, W, WC and Al2O3 were applied to FSW of 304 stainless steel, and then the wear and reaction between the tool debris and the steel matrix were examined for each tool material. Severe tool damage was found in W, WC and Al2O3 tools after FSW, while the PCBN tool was hardly worn. Formations of Cr-rich borides, ferrite phases containing the high W contents and Cr-rich carbides were found in the stir zones produced using PCBN, W and WC tools, respectively. It was suggested that formation of those phases could be expected by calculation using the thermochemical database.

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Nam, Nguyen Hong, Vu Ngoc Linh, Le Duc Dung, and Vu Thi Thu Ha. "Physico‐chemical characterization of forest and agricultural residues for energy conversion processes." Vietnam Journal of Chemistry 58, no. 6 (2020): 735–41. http://dx.doi.org/10.1002/vjch.202000054.

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AbstractAgricultural and forest residues could become potential sources of energy in various countries. However, incomplete understanding regarding physico‐chemical properties of these residues presents the main challenges for energy conversion processes. This study presented a complete and comprehensive database of characteristics and compositions of a wide range of agricultural and forest residues. Physical characteristics (moisture, bulk density, calorific value, volatile matter, fixed‐carbon content, and ash content), elemental compositions (C, H, N, O, and S), as well as lignocellulosic compositions (cellulose, hemicellulose, and lignin) of ten biomass residues were analyzed. The major impacts of the variability in biomass compositions to biochemical and thermochemical processes were also discussed.

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Tennyson, Jonathan, Peter F. Bernath, Linda R. Brown, et al. "A database of water transitions from experiment and theory (IUPAC Technical Report)." Pure and Applied Chemistry 86, no. 1 (2014): 71–83. http://dx.doi.org/10.1515/pac-2014-5012.

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Abstract The report and results of an IUPAC Task Group (TG) formed in 2004 on “A Database of Water Transitions from Experiment and Theory” (Project No. 2004-035-1-100) are presented. Energy levels and recommended labels involving exact and approximate quantum numbers for the main isotopologues of water in the gas phase, H216O, H218O, H217O, HD16O, HD18O, HD17O, D216O, D218O, and D217O, are determined from measured transition frequencies. The transition frequencies and energy levels are validated using first-principles nuclear motion computations and the MARVEL (measured active rotational–vibrational energy levels) approach. The extensive data including lines and levels are required for analysis and synthesis of spectra, thermochemical applications, the construction of theoretical models, and the removal of spectral contamination by ubiquitous water lines. These datasets can also be used to assess where measurements are lacking for each isotopologue and to provide accurate frequencies for many yet-to-be measured transitions. The lack of high-quality frequency calibration standards in the near infrared is identified as an issue that has hindered the determination of high-accuracy energy levels at higher frequencies. The generation of spectra using the MARVEL energy levels combined with transition intensities computed using high accuracy ab initio dipole moment surfaces are discussed. A recommendation of the TG is for further work to identify a single, suitable model to represent pressure- (and temperature-) dependent line profiles more accurately than Voigt profiles.

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Delpech, Sylvie. "Possible routes for pyrochemical separation: Focus on the reductive extraction in fluoride media." Pure and Applied Chemistry 85, no. 1 (2012): 71–87. http://dx.doi.org/10.1351/pac-con-12-04-06.

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Molten salts (MSs) such as fluoride or chloride salts at high temperature (400–800 °C) are solvents known for their high solvation power and electroactivity range. Rare earths, lanthanides, actinides, and refractory metals can be dissolved, treated, and purified in MSs. The properties of these solvents are particularly interesting for nuclear spent-fuel reprocessing. The pyrochemical separation and extraction of solutes can be performed using several methods taking into account the effects of redox and/or acidity. This paper is focused on the reductive extraction method performed by contacting a liquid metal (LM) containing reductive species and an MS. The analytical model developed to calculate the efficiency of such a method is detailed in this paper. To apply this model, one essential point is the establishment of a database related to the redox and solvation properties of solutes in MSs. The approach retained to propose a database based on the analysis of both thermochemical data of pure compounds and experimental measurements reported in the literature is described in this paper in the case of lanthanides in fluoride MSs. The use of the database to calculate efficiency as a function of process parameters is given in this paper as well as the comparison between two reducing agents considered.

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Fache, Maxime, Laura Voigt, Jean-Yves Colle, John Hald, and Ondřej Beneš. "Thermophysical Properties of FUNaK (NaF-KF-UF4) Eutectics." Materials 17, no. 11 (2024): 2776. http://dx.doi.org/10.3390/ma17112776.

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General interest in the deployment of molten salt reactors (MSRs) is growing, while the available data on uranium-containing fuel salt candidates remains scarce. Thermophysical data are one of the key parameters for reactor design and understanding reactor operability. Hence, filling in the gap of the missing data is crucial to allow for the advancement of MSRs. This study provides novel data for two eutectic compositions within the NaF-KF-UF4 ternary system which serve as potential fuel candidates for MSRs. Experimental measurements include their melting point, density, fusion enthalpy, and vapor pressure. Additionally, their boiling point was extrapolated from the vapor pressure data, which were, at the same time, used to determine the enthalpy of vaporization. The obtained thermodynamic values were compared with available data from the literature but also with results from thermochemical equilibrium calculations using the JRCMSD database, finding a good correlation, which thus contributed to database validation. Preliminary thoughts on fluoride salt reactor operability based on the obtained results are discussed in this study.

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Lee, Hyuck Mo, Samuel M. Allen, and Mica Grujicic. "Coarsening resistance of M2C carbides in secondary hardening steels: Part II. Alloy design aided by a thermochemical database." Metallurgical Transactions A 22, no. 12 (1991): 2869–76. http://dx.doi.org/10.1007/bf02650248.

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Karton, Amir. "Three decades of quantum science: how quantum chemistry transformed thermochemical database generation for benchmarking DFT and machine learning." Australian Journal of Chemistry 78, no. 3 (2025): NULL. https://doi.org/10.1071/ch24130.

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Jenkins, Harry Donald Brooke. "Recent Initiatives in Experimental Thermodynamic Studies on Ionic Liquids [IL]-the Emergence of a Standard Thermochemical Database for ILs." Science Progress 94, no. 2 (2011): 184–210. http://dx.doi.org/10.3184/003685011x13051250311491.

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Sevastyanov, V. G., D. V. Sevastyanov, E. V. Peresypkina, V. A. Blatov, and N. T. Kuznetsov. "Vaporization of Molecular Coordination Organotitanium Compounds: Development of the Structure-Thermochemical Approach with Programmed Use of the Cambridge Structural Database." Russian Journal of Coordination Chemistry 30, no. 10 (2004): 679–84. http://dx.doi.org/10.1023/b:ruco.0000043890.58352.1f.

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Costa, Davide, and Maria-Eleni Ragoussi. "Selection of Reference Thermodynamic Data for Modelling of Deep Geological Repositories: Present and Future of the NEA Thermochemical Database Project." Journal of Solution Chemistry 46, no. 9-10 (2017): 1760–66. http://dx.doi.org/10.1007/s10953-017-0631-x.

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Spear, Karl E., Theodore M. Besmann, and Edward C. Beahm. "Thermochemical Modeling of Glass: Application to High-Level Nuclear Waste Glass." MRS Bulletin 24, no. 4 (1999): 37–44. http://dx.doi.org/10.1557/s0883769400052179.

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Despite the obvious importance of understanding the chemistry of oxide glass materials, predictive thermochemical modeis of complex glasses have not yet been developed. Such modeis are important for technologies such as the disposal of high-level nuclear and transuranic waste (HLW), which are currently fore-seen as being incorporated in a host glass for permanen t Sequestration. A large number of glasses have been explored, with a borosilicate glass being the typical base composition. An example of the complexity of such a HLW glass is given in Table I. This article discusses our at-tempts to develop an accurate, easy to understand and use glass Solution model for describing the thermodynamic stability of such HLW glasses. Critical for such a model is the availability of reliable thermodynamic data that can be used in generating accurate values for thermodynamic activities of glass components as a function of temperature and glass composition. Therefore, a major part of this article focuses on developing reliable sets of thermodynamic data for complex HLW glass Systems and Subsystems. With such Information and a model, we can make predictions of the stability of these waste forms, including their volatility, leaching behavior, and corrosion reactions, and understand crystallization behavior during both the initial glass processing and long-term storage.Using an equilibrium thermodynamic model is offen questioned, since HLW is to be stored as part of a glass phase, and glass is a nonequilibrium material. Our model uses a pseudoequilibriu map-proach in which we thermochemically treat the glass as a supercooled liquid. This is a more accurate approach than assuming a global System equilibrium, as it describes the behavior of the metas-table glass phase using thermodynamic data for the liquid phase and excludes the formation of crystalline species. As a result, developing an accurate model and data for representing the thermodynamic properties of oxide liquid phases is critical to understanding the limiting chemi-cal behavior of the nuclear waste glass.The methodology requires that a critically assessed thermodynamic database be created for binary and ternary combinations of the major constituents in a typical waste glass. These data can then be combined to represent the thermodynamic behavior of the more complex multicomponent HLW glass Systems. If a crystalline phase is experimentally observed to precipitate from the glass under certain conditions, a thermodynamic description can be used to calculate the composition-temperature conditions under which this specific crystalline phase can exist in equilibrium with the metas-table glass phase.

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Ard, Johnathon C., Jacob A. Yingling, Kaitlin E. Johnson, et al. "Development of the Molten Salt Thermal Properties Database − Thermochemical (MSTDB−TC), example applications, and LiCl−RbCl and UF3−UF4 system assessments." Journal of Nuclear Materials 563 (May 2022): 153631. http://dx.doi.org/10.1016/j.jnucmat.2022.153631.

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Ragoussi, Maria-Eleni, and Davide Costa. "Fundamentals of the NEA Thermochemical Database and its influence over national nuclear programs on the performance assessment of deep geological repositories." Journal of Environmental Radioactivity 196 (January 2019): 225–31. http://dx.doi.org/10.1016/j.jenvrad.2017.02.019.

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Tang, Kai, Azam Rasouli, Jafar Safarian, Xiang Ma, and Gabriella Tranell. "Magnesiothermic Reduction of Silica: A Machine Learning Study." Materials 16, no. 11 (2023): 4098. http://dx.doi.org/10.3390/ma16114098.

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Fundamental studies have been carried out experimentally and theoretically on the magnesiothermic reduction of silica with different Mg/SiO2 molar ratios (1–4) in the temperature range of 1073 to 1373 K with different reaction times (10–240 min). Due to the kinetic barriers occurring in metallothermic reductions, the equilibrium relations calculated by the well-known thermochemical software FactSage (version 8.2) and its databanks are not adequate to describe the experimental observations. The unreacted silica core encapsulated by the reduction products can be found in some parts of laboratory samples. However, other parts of samples show that the metallothermic reduction disappears almost completely. Some quartz particles are broken into fine pieces and form many tiny cracks. Magnesium reactants are able to infiltrate the core of silica particles via tiny fracture pathways, thereby enabling the reaction to occur almost completely. The traditional unreacted core model is thus inadequate to represent such complicated reaction schemes. In the present work, an attempt is made to apply a machine learning approach using hybrid datasets in order to describe complex magnesiothermic reductions. In addition to the experimental laboratory data, equilibrium relations calculated by the thermochemical database are also introduced as boundary conditions for the magnesiothermic reductions, assuming a sufficiently long reaction time. The physics-informed Gaussian process machine (GPM) is then developed and used to describe hybrid data, given its advantages when describing small datasets. A composite kernel for the GPM is specifically developed to mitigate the overfitting problems commonly encountered when using generic kernels. Training the physics-informed Gaussian process machine (GPM) with the hybrid dataset results in a regression score of 0.9665. The trained GPM is thus used to predict the effects of Mg-SiO2 mixtures, temperatures, and reaction times on the products of a magnesiothermic reduction, that have not been covered by experiments. Additional experimental validation indicates that the GPM works well for the interpolates of the observations.

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Abejón, Ricardo, Heriberto Pérez-Acebo, and Leonardo Clavijo. "Alternatives for Chemical and Biochemical Lignin Valorization: Hot Topics from a Bibliometric Analysis of the Research Published During the 2000–2016 Period." Processes 6, no. 8 (2018): 98. http://dx.doi.org/10.3390/pr6080098.

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A complete bibliometric analysis of the Scopus database was performed to identify the research trends related to lignin valorization from 2000 to 2016. The results from this analysis revealed an exponentially increasing number of publications and a high relevance of interdisciplinary collaboration. The simultaneous valorization of the three main components of lignocellulosic biomass (cellulose, hemicellulose, and lignin) has been revealed as a key aspect and optimal pretreatment is required for the subsequent lignin valorization. Research covers the determination of the lignin structure, isolation, and characterization; depolymerization by thermal and thermochemical methods; chemical, biochemical and biological conversion of depolymerized lignin; and lignin applications. Most methods for lignin depolymerization are focused on the selective cleavage of the β-O-4 linkage. Although many depolymerization methods have been developed, depolymerization with sodium hydroxide is the dominant process at industrial scale. Oxidative conversion of lignin is the most used method for the chemical lignin upgrading. Lignin uses can be classified according to its structure into lignin-derived aromatic compounds, lignin-derived carbon materials and lignin-derived polymeric materials. There are many advances in all approaches, but lignin-derived polymeric materials appear as a promising option.

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El Zrelli, Radhouan Belgacem, Jessica K. Klar, Sylvie Castet, Michel Grégoire, Pierre Courjault-Radé, and Sébastien Fabre. "Spatial Distribution Patterns, Eco-Environmental Risk Assessment, and Human Health Impacts of Uranium and Thorium in Beach Sediments in the Central Gulf of Gabes (Southern Mediterranean Sea)." Sustainability 17, no. 3 (2025): 1283. https://doi.org/10.3390/su17031283.

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This study investigates uranium (U) and thorium (Th) levels in surface beach sediments from the Central Gulf of Gabes (SE Tunisia), aiming to identify concentration zones, geochemical behaviors, and enrichment factors. U concentrations ranged from 0.71 to 38.00 mg/kg, exceeding Th levels, which ranged from 1.00 to 10.60 mg/kg. A positive correlation between U and Th indicates a common source, which is most likely phosphogypsum wastes, and similar geochemical behaviors. The central sector near Gabes’ fertilizer factories showed the highest U and Th concentrations, with factors such as proximity to industrial discharge, port structures’ influence, organic matter enrichment, low seawater pH, and high phosphorus levels affecting the spatial distribution of these elements. Thermochemical analysis suggests that U and Th exhibit parallel chemical behaviors in low-pH, phosphate-rich conditions. This is the first study to document U and Th presence in phosphogypsum-contaminated beach sediments in Gabes, underlining potential risks to the environment and human health. The findings of this work contribute to the international database of U and Th contamination in coastal sediments, providing essential data to support sustainable strategies aimed at safeguarding human health and preserving local environments affected by phosphate fertilizer industry pollution.

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Assunção, Fernanda Paula da Costa, Diogo Oliveira Pereira, Jéssica Cristina Conte da Silva, et al. "A Systematic Approach to Thermochemical Treatment of Municipal Household Solid Waste into Valuable Products: Analysis of Routes, Gravimetric Analysis, Pre-Treatment of Solid Mixtures, Thermochemical Processes, and Characterization of Bio-Oils and Bio-Adsorbents." Energies 15, no. 21 (2022): 7971. http://dx.doi.org/10.3390/en15217971.

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This work aims to investigate the effect of process temperature and catalyst content by pyrolysis and thermal catalytic cracking of (organic matter + paper) fraction from municipal household solid waste (MHSW) on the yields of reaction products (bio-oil, bio-char, H2O, and gas), acid value, chemical composition of bio-oils, and characterization of bio-chars in laboratory scale. The collecting sectors of MHSW in the municipality of Belém-Pará-Brazil were chosen based on geographic and socio-economic database. The MHSW collected and transported to the segregation area. The gravimetric analysis of MHSW was carried out and the fractions (Paper, Cardboard, Tetra Pack, Hard Plastic, Soft Plastic, Metal, Glass, Organic Matter, and Inert) were separated. The selected organic matter and paper were submitted to pre-treatment of crushing, drying, and sieving. The experiments carried out at 400, 450, and 475 °C and 1.0 atmosphere, and at 475 °C and 1.0 atmosphere, using 5.0, 10.0, and 15.0% (wt.) Ca(OH)2, in batch mode. The bio-oil was characterized for acid value. The chemical functions present in bio-oil were identified by FT-IR and the composition was identified by GC-MS. The bio-char was characterized by SEM, FT-IR, and XRD. The variance in mass (wt.%) for organic fractions of municipal household solid waste (OFMHSW), between 56.21 and 67.45% (wt.), lies with the interval of 56% (wt.) and 64% (wt.) of OFMHSW for middle- and low-income countries. The pyrolysis of MHSW fraction (organic matter + paper) shows bio-oil yields between 2.63 and 9.41% (wt.), aqueous phase yields between 28.58 and 35.08% (wt.), solid phase yields between 35.29 and 45.75% (wt.), and gas yields between 16.54 and 26.72% (wt.). The bio-oil yield increases with pyrolysis temperature. For the catalytic cracking, the bio-oil and gas yields increase slightly with CaO content, while that of bio-char decreases, and the H2O phase remains constant. The GC-MS of liquid reaction products identified the presence of hydrocarbons (alkanes, alkenes, alkynes, cycloalkanes, and aromatics) and oxygenates (carboxylic acids, ketones, esters, alcohols, phenols, and aldehydes), as well as compounds containing nitrogen, including amides and amines. The acidity of bio-oil decreases with increasing process temperature and with aid Ca(OH)2 as a catalyst. The concentration of hydrocarbons in bio-oil increases with increasing Ca(OH)2-to-OFMHSW fraction ratio due to the catalytic deoxygenation of fatty acid molecules, by means of decarboxylation/decarbonylation, producing aliphatic and aromatic hydrocarbons.

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Podkin, E. S., I. O. Gilev, and A. B. Shubin. "Thermodynamic modeling of liquid binary alloys of the Al–Er system." Rasplavy, no. 3 (October 7, 2024): 282–94. http://dx.doi.org/10.31857/s0235010624030054.

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The paper presents the results of a study of the thermochemical properties of the Al–Er system. The thermodynamic characteristics were evaluated (△fH0298, S0298, (H0298−H00), Cp(T) and Cp(liq)) for the intermetallic compounds Al3Er, Al2Er, AlEr, Al2Er3, AlEr2. The values of△fH0298 calculated based on the semiempirical Miedema model adapted for the group of Al–REM alloys were taken for calculations and amounted to –47.7, –58.4, –63, –55.2, –46.8 kJ/mol∙at, respectively. The mixing characteristics of liquid alloys of this system were evaluated by Terra software package for modeling the equilibrium states of heterogeneous inorganic systems with an extensive database of properties of individual substances. The model of ideal solutions of interaction products was used as a computational model. Modeling of equilibrium composition and properties of melts was carried out in the temperature range of 1900–2100 K, in an argon atmosphere at a total pressure of 0.1 MPa in the system. Comparison of the obtained results with the simulation results in the approximation of an ideal solution, allowed us to determine the excess integral thermodynamic properties of liquid alloys (Gibbs energy, enthalpy, and entropy). It is shown that in the studied temperature range, with an increase of temperature, there is a natural, though not significant, decrease in the values of these parameters by absolute value. It is established that the formation of liquid alloys of the Al–Er system is accompanied by significant heat release: the value of the integral enthalpy of mixing at a temperature T = 2100 K is –58.9 kJ/ mol∙at. When comparing the thermochemical properties of the Al–Er system with the binary systems Al–Y and Al–Sc studied by the same methods, it is shown that all energy curves pass through the extremum at XSc,Y,Er ≈ 0.5. The strongest interaction of the components is observed in the Al–Y system, (ΔHmix = –58.9 kJ/mol∙at), which is close enough to the maximum modulo value of the enthalpy of mixing in the Al–Er system. The weakest interaction is observed in the Al–Sc system (ΔHmix = –44.8 kJ/mol·at). The results obtained in this work provide a theoretical basis for further experimental study of erbium–containing aluminum alloys.

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Lyu, Renzhi, Zhenpo Wang, and Zhaosheng Zhang. "Life Cycle Assessment Based on Whole Industry Chain Assessment of FCEVs." Sustainability 17, no. 12 (2025): 5431. https://doi.org/10.3390/su17125431.

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Fuel cell electric vehicles (FCEVs) offer a promising solution for energy saving and emission reduction in transportation. However, several challenges must be addressed for their application. This study conducts a full life cycle assessment (LCA) of FCEVs, dividing it into the fuel cycle and vehicle cycle to separately assess energy consumption (EC) and emissions. The fuel cycle examined 18 hydrogen production–storage–transport pathways, while the vehicle cycle evaluates energy use and emissions associated with vehicle component production, assembly, disposal, battery production, and fluid consumption. Based on the GREET database, total energy consumption and emissions over a lifetime were calculated. Five environmental impact indicators were used for evaluation, and a comprehensive environmental assessment (CEA) indicator was established for different scenarios. Results indicate that nuclear thermochemical water splitting is the best hydrogen production method, and pipeline transportation is the most efficient for hydrogen transport. Additionally, water electrolysis for hydrogen production is only practical when paired with renewable energy. The study also identified that the Hydrogen production method, “Body”, “Proton Exchange Membrane Fuel Cells (PEMFCs) System”, “Chassis”, “Hydrogen Storage System” and lifetime significantly impact energy consumption and emissions. These stages or products represent high-impact leverage points for enhancing the lifecycle sustainability evaluation of FCEVs.

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Skerencak-Frech, Andrej, Petra Panak, Kathy Dardenne, et al. "Impact of increased temperatures on the geochemical behaviour of trivalent actinides in aquatic systems." Safety of Nuclear Waste Disposal 1 (November 10, 2021): 159–60. http://dx.doi.org/10.5194/sand-1-159-2021.

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Abstract. The Safety Case for a radioactive waste repository in deep geological formations requires detailed chemical and thermodynamic information on the stored radionuclides in their relevant oxidation states. Although a comprehensive summary of critically evaluated thermodynamic data is available via the blue book series of the NEA-TDB (“Nuclear Energy Agency – Thermochemical Database”), the majority of this data is limited to ambient conditions (Grenthe et al., 2020). In the case of the disposal of high-active, heat-producing waste, however, the near-field of the repository will experience increased temperatures at early operative phases for several hundred or a few thousand years. Radionuclides may come into contact with aquatic solutions or brines at elevated temperatures in the case of early canister failure. Besides other factors of the overall disposal concept (e.g. the geometry of the repository, type and amount of stored radionuclide inventories), host rock characteristics themselves limit the extent of the allowable temperature increase. For example, in clay formations the maximum temperature should stay at around or below ∼100∘C in order to avoid an irreversible change in the host rock retention capacity, whereas rock salt allows much higher temperatures of up to 200 ∘C. Increased temperatures will have a distinct impact on the geochemical behaviour of radionuclides, potentially affecting their mobility and retention in the near field. Besides reactions at the solid–liquid interface (e.g. dissolution/precipitation reactions of the waste matrix, sorption reactions of the radionuclides to surfaces), complexation reactions with inorganic and organic ligands present in the aqueous phase potentially affect migration behaviour of the radionuclides. A quantitative thermodynamic description of these processes requires standard stability constants (log⁡βn0(T)), as well as standard reaction enthalpies and entropies (ΔrHm,n0, ΔrSm,n0). The precise experimental determination of these data for all relevant radionuclide/ligand reactions requires a vast amount of time and effort. In this regard, reliable extrapolation methods in particular for standard stability constants valid for 25 ∘C to higher temperatures are considered to support a comprehensive description. Recently, the German Federal Ministry of Education and Research (BMBF)-funded collaborative research project “Therm AC” focused on the experimental determination of new thermodynamic data at higher temperatures, as well as the comparison with the analogous results yielded by extrapolation methods. The Thermochemical Database Project of the OECD-NEA (NEA-TDB) is currently in the process of preparing a comprehensive state-of-the-art report on the high temperature thermodynamics of radionuclides, further emphasizing the particular relevance of this interesting topic. Within this contribution, a critical overview on the recent advances in the field of high temperature studies of radionuclides in aqueous solutions will be given. Besides summarizing information on key technical aspects relevant for high temperature studies, the effect of increased temperatures on the complexation of trivalent actinides with chloride will be discussed in more detail in order to illustrate newly derived in-depth understanding of the impact of increased temperatures on the (geo)chemical behaviour of trivalent actinides on the molecular scale (Skerencak-Frech et al., 2014).

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Barrachin, Marc. "Corium Experimental Thermodynamics: A Review and Some Perspectives." Thermo 1, no. 2 (2021): 179–204. http://dx.doi.org/10.3390/thermo1020013.

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More than 30 years ago a specialist meeting was held at Joint Research Center Ispra (Italy) from 15 to 17 January 1990 to review the current understanding of chemistry during severe accidents in light water reactors (LWR). Let us consider that, at the end of the 1980s, thermodynamics introduced in the severe accident codes was really poor. Only some equilibrium constants for a few simple reactions between stoichiometric compounds were used as well as some simple correlations giving estimates of solidus and liquidus temperatures. In the same time, the CALPHAD method was developed and was full of promise to approximate the thermodynamic properties of a complex thermochemical system by the way of a critical assessment of experimental data, a definition of a simple physical model and an optimisation procedure to define the values of the model parameters. It was evident that a nuclear thermodynamic database had to be developed with that new technique to obtain quite rapidly prominent progress in the knowledge of thermochemistry in the severe accident research area. Discussions focused on the important chemical phenomena that could occur across the wide range of conditions of a damaged nuclear plant. The most pressing need for improved chemical models is identified with condensed phase mixtures to model the corium progression. This paper reviews more than 30 years of experimental data production in the field of corium thermodynamics. This work has been conducted through multiple international programs (EURATOM, ISTC, OECD) as well as through more specific studies conducted at the national scale. This research has been capitalised in specific databases such as NUCLEA and TAF-ID, databases developed at IRSN and at CEA, respectively, and are now used in degradation models of the severe accident simulation codes. This research is presented in this paper. In the conclusion, we outline the research perspectives that need to be considered in order to address today’s and tomorrow’s issues.

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Vuori, Hannu T., J. Mikko Rautiainen, Erkki T. Kolehmainen, and Heikki M. Tuononen. "High-Level Ab Initio Predictions of Thermochemical Properties of Organosilicon Species: Critical Evaluation of Experimental Data and a Reliable Benchmark Database for Extending Group Additivity Approaches." Journal of Physical Chemistry A 126, no. 10 (2022): 1729–42. http://dx.doi.org/10.1021/acs.jpca.1c09980.

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Vukovic, Natalia, and Evgenia Makogon. "Waste-to-Energy Generation: Complex World Project Analysis." Sustainability 16, no. 9 (2024): 3531. http://dx.doi.org/10.3390/su16093531.

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Sustainable development and the circular economy mandate efficacious management of waste. The annually increasing volumes of municipal solid waste pose a formidable global challenge. Waste-to-energy conversion, utilizing thermochemical or biochemical technologies, presents a viable solution for mitigating waste disposal concerns. This study conducts a thorough analysis of extant projects to evaluate the economic viability and environmental benefits across various technologies. Employing a self-compiled, unique database, our examination spans enterprises operational from 1980 to 2022, including 37 of the most representative facilities across Europe, North America, and East and Southeast Asia. Economic efficiency is gauged through the levelized cost of electricity generated by these installations, while environmental impacts are assessed based on the statistics on prevented greenhouse gas emissions. The methodology encompasses correlation and techno–economic analyses and expert evaluation. Contrary to conventional wisdom, our findings challenge the ubiquity of scale effects among technologies and the presumed decline in electricity generation costs with newer technologies. However, they corroborate the enhanced environmental benefits of recent technological advancements. The insights derived from this research are poised to inform strategic municipal solid waste management planning in Russia and beyond, offering a foundation for the design of new facilities. The scientific novelty of this work lies in its holistic approach to analyzing the ecological and economic efficiencies of all extant technologies.

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Fellhauer, David, Xavier Gaona, Marcus Altmaier, and Horst Geckeis. "Radionuclide geochemistry: solubility and thermodynamics in an HLW repository." Safety of Nuclear Waste Disposal 1 (November 10, 2021): 149–50. http://dx.doi.org/10.5194/sand-1-149-2021.

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Abstract. Deep geological disposal is the internationally favoured option to isolate high-level nuclear waste (HLW) from the biosphere and to minimise the potential radiological risk for future generations. Potentially contacting aqueous solutions such as groundwater may, however, lead to the corrosion of the solid casks containing the nuclear waste, and the formation of aqueous radionuclide systems in the near-field of the emplacement rooms. As dissolved species, radionuclides can in principle further migrate into the far-field and finally reach the biosphere on medium and long timescales. Like all chemical species, the radionuclides are subject to fundamental (geo)chemical laws. Relevant reactions that control retention and release, and hence, the migration behaviour and fate of radionuclides in a repository, are solubility equilibria, formation of soluble complexes, redox reactions, sorption on and incorporation into mineral surfaces, transport phenomena etc. These processes depend directly on the (geo)chemical boundary conditions, and, consequently, can differ greatly for various host rock systems such as clay rock, rock salt, and crystalline rock. Many of the radionuclides in HLW are heavy metals that are sparingly soluble under various repository-relevant conditions, e.g. actinides, lanthanides, transition metals, so that only partial dissolution (mobilisation) from the solid waste matrices is expected. This underlines the importance of evaluating the radionuclide solubility within a geochemically based safety assessment for repositories as it provides reliable upper-limit concentrations of the mobile, potentially migrating radionuclide fraction in the near-field. In this contribution, we discuss relevant aspects related to the topic radionuclide solubility and thermodynamics in a HLW repository. This includes a summary of recent laboratory studies on the solubility behaviour and speciation of key radionuclides in repository-relevant solutions, which are an important basis for obtaining (geo)chemical information and models, and the corresponding fundamental thermodynamic constants on aqueous radionuclide systems. National and international thermodynamic database projects, where quality-assured thermodynamic data (solubility products, complex formation constants, and ion-interaction parameters) are evaluated and compiled, e.g. the Nuclear Energy Agency Thermochemical Database (http://www.oecd-nea.org, last access: 1 November 2021) or the Thermodynamic Reference Database (http://www.thereda.de, last access: 1 November 2021), are highlighted and the main remaining uncertainties discussed. The experimental information and the quantitative thermodynamic data are applied within a generic case study to demonstrate the impact of different geochemical solution conditions representing different host rock systems considered as HLW repositories in Germany on the solubility and speciation of selected radionuclides.

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Bale, Christopher W., and Gunnar Eriksson. "Metallurgical Thermochemical Databases—A Review." Canadian Metallurgical Quarterly 29, no. 2 (1990): 105–32. http://dx.doi.org/10.1179/cmq.1990.29.2.105.

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Bale, C. W., P. Chartrand, S. A. Degterov, et al. "FactSage thermochemical software and databases." Calphad 26, no. 2 (2002): 189–228. http://dx.doi.org/10.1016/s0364-5916(02)00035-4.

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Bursch, Markus, Hagen Neugebauer, Sebastian Ehlert, and Stefan Grimme. "Dispersion corrected r²SCAN based global hybrid functionals: r²SCANh, r²SCAN0, and r²SCAN50." Journal of Chemical Physics 156, no. 13 (2022): 134105. http://dx.doi.org/10.1063/5.0086040.

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The regularized and restored semilocal meta-generalized gradient approximation (meta-GGA) exchange–correlation functional r2SCAN [Furness et al., J. Phys. Chem. Lett. 11, 8208–8215 (2020)] is used to create three global hybrid functionals with varying admixtures of Hartree–Fock “exact” exchange (HFX). The resulting functionals r2SCANh (10% HFX), r2SCAN0 (25% HFX), and r2SCAN50 (50% HFX) are combined with the semi-classical D4 London dispersion correction. The new functionals are assessed for the calculation of molecular geometries, main-group, and metalorganic thermochemistry at 26 comprehensive benchmark sets. These include the extensive GMTKN55 database, ROST61, and IONPI19 sets. It is shown that a moderate admixture of HFX leads to relative improvements of the mean absolute deviations for thermochemistry of 11% (r2SCANh-D4), 16% (r2SCAN0-D4), and 1% (r2SCAN50-D4) compared to the parental semi-local meta-GGA. For organometallic reaction energies and barriers, r2SCAN0-D4 yields an even larger mean improvement of 35%. The computation of structural parameters (geometry optimization) does not systematically profit from the HFX admixture. Overall, the best variant r2SCAN0-D4 performs well for both main-group and organometallic thermochemistry and is better or on par with well-established global hybrid functionals, such as PW6B95-D4 or PBE0-D4. Regarding systems prone to self-interaction errors (SIE4x4), r2SCAN0-D4 shows reasonable performance, reaching the quality of the range-separated ωB97X-V functional. Accordingly, r2SCAN0-D4 in combination with a sufficiently converged basis set [def2-QZVP(P)] represents a robust and reliable choice for general use in the calculation of thermochemical properties of both main-group and organometallic chemistry.

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Jiang, Qi, Yongmei He, Yonglin Wu, et al. "Predicting the Release and Migration of Potentially Harmful Elements (PHEs) during the Lightweight Ceramsite Preparation from Carbide Slag." Minerals 13, no. 2 (2023): 216. http://dx.doi.org/10.3390/min13020216.

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When preparing lightweight ceramsite using carbide slag, trace amounts of toxic elements are released into the atmosphere due to high-temperature calcination, posing a significant risk to the environment. The real-time monitoring of the released gases is challenging under laboratory conditions while preparing large quantities of ceramsite. Therefore, heating was simulated using experimental data and the FactSage 7.0 thermochemical database to study the release of harmful Al-, C-, H-, S-, and F-containing elements when using carbide slag to prepare lightweight ceramsite. The results indicated that no Al, C, H, S, or F elements were evident in the high-temperature liquid products obtained in a 50 °C to 1150 °C calcination temperature range. Al was present in a solid state with no gaseous products. When the temperature reached 450 °C, CO gas was released and its level increased as the temperature rose. H and S mainly combined into H2S gas, starting at 250 °C and reaching a peak at 1050 °C. H and F primarily combined into HF, starting at 400 °C. Other F-containing gases mainly included SiF4 and TiF3, which began to release at 800 °C and 900 °C, respectively. The release trends of HF, SiF4, and TiF3 were consistent with those of CO. This study aimed to conduct an environmental impact and management assessment for the preparation of lightweight ceramsite using carbide slag. The use of raw material carbide slag for the low-cost treatment of tail gas was proposed, which provides theoretical and up-to-date support for greening the application of the process.

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Deary, Michael E., Patrick M. Amaibi, John R. Dean, and Jane A. Entwistle. "New Insights into Health Risk Assessments for Inhalational Exposure to Metal(loid)s: The Application of Aqueous Chemistry Modelling in Understanding Bioaccessibility from Airborne Particulate Matter." Geosciences 11, no. 2 (2021): 47. http://dx.doi.org/10.3390/geosciences11020047.

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Aqueous modelling of chemical speciation in simulated lung fluid (SLF) enables a better understanding of the underlying chemical factors that influence metal(loid) inhalation bioaccessibility from airborne particulate matter. Such an approach can be used to supplement experimental techniques that are integral to the health risk assessment of metal(loid) exposure by inhalational routes. In this paper, we modelled the aqueous chemistry of airborne particulate-bound metal(loid)s (As, Cu, Mn, Pb and Zn) in a SLF based on Gamble’s solution (neutral pH). The modelling was performed using two software packages (Geochemist’s Workbench 14 and OLI Studio 9.5) and a total of five thermochemical databases (GWB Thermo, MINTEQ, PHREEQC, WATEQ4F and the default database for OLI Studio). Modelled results were compared with experimentally determined bioaccessibilities for the NIST 2710a standard reference material (SRM) and with literature-reported bioaccessibilities for NIST 1648a and BCR 038 SRMs. Whilst the models correctly describe the observed increase in bioaccessibility for more dilute solid/liquid extraction ratios, the performance of the models against the fractional bias of the mean (FBmean) and the normalised mean square error (NMSE) statistical metrics was generally outside the acceptance criteria. Findings from an analysis of the main aqueous chemical species predicted to be present in SLF indicate that carbonate and chloride complexes of Cu, Mn, Pb and Zn predominate, whilst free cations (for Cu, Mn and Zn) and hydroxides (for Cu) also play a role in solubilisation. Arsenic is not predicted to form significant complexes with the SLF components and is present in solution mainly as the HAsO42− ion and its conjugate acid, H2AsO4−. For modelled runs where glycine and citrate were present, significant increases in the bioavailability of Cu and Zn were predicted as a result of complexation with these ligands. An additional finding from our experimental bioaccessibility results for NIST 2710a was that the inclusion of the lung fluid surfactant dipalmitoylphosphatidylcholine (DPPC) in the SLF did not significantly affect the bioaccessibility. Our study provides useful insights into the likely aqueous- and solid-phase speciation of metal(loid)s in SLF and highlights that future developments in this area should consider the role of mineralogy and surface interactions.

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Agúndez, M., J. I. Martínez, P. L. de Andres, J. Cernicharo, and J. A. Martín-Gago. "Chemical equilibrium in AGB atmospheres: successes, failures, and prospects for small molecules, clusters, and condensates." Astronomy & Astrophysics 637 (May 2020): A59. http://dx.doi.org/10.1051/0004-6361/202037496.

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Chemical equilibrium has proven extremely useful for predicting the chemical composition of AGB atmospheres. Here we use a recently developed code and an updated thermochemical database that includes gaseous and condensed species involving 34 elements to compute the chemical equilibrium composition of AGB atmospheres of M-, S-, and C-type stars. We include for the first time TixCy clusters, with x = 1–4 and y = 1–4, and selected larger clusters ranging up to Ti13C22, for which thermochemical data are obtained from quantum-chemical calculations. Our main aims are to systematically survey the main reservoirs of each element in AGB atmospheres, review the successes and failures of chemical equilibrium by comparing it with the latest observational data, identify potentially detectable molecules that have not yet been observed, and diagnose the most likely gas-phase precursors of dust and determine which clusters might act as building blocks of dust grains. We find that in general, chemical equilibrium reproduces the observed abundances of parent molecules in circumstellar envelopes of AGB stars well. There are, however, severe discrepancies of several orders of magnitude for some parent molecules that are observed to be anomalously overabundant with respect to the predictions of chemical equilibrium. These are HCN, CS, NH3, and SO2 in M-type stars, H2O and NH3 in S-type stars, and the hydrides H2O, NH3, SiH4, and PH3 in C-type stars. Several molecules have not yet been observed in AGB atmospheres but are predicted with non-negligible abundances and are good candidates for detection with observatories such as ALMA. The most interesting ones are SiC5, SiNH, SiCl, PS, HBO, and the metal-containing molecules MgS, CaS, CaOH, CaCl, CaF, ScO, ZrO, VO, FeS, CoH, and NiS. In agreement with previous studies, the first condensates predicted to appear in C-rich atmospheres are found to be carbon, TiC, and SiC, while Al2O3 is the first major condensate expected in O-rich outflows. According to our chemical equilibrium calculations, the gas-phase precursors of carbon dust are probably acetylene, atomic carbon, and/or C3, while for silicon carbide dust, the most likely precursors are the molecules SiC2 and Si2C. In the case of titanium carbide dust, atomic Ti is the major reservoir of this element in the inner regions of AGB atmospheres, and therefore it is probably the main supplier of titanium during the formation of TiC dust. However, chemical equilibrium predicts that large titanium-carbon clusters such as Ti8C12 and Ti13C22 become the major reservoirs of titanium at the expense of atomic Ti in the region where condensation of TiC is expected to occur. This suggests that the assembly of large TixCy clusters might be related to the formation of the first condensation nuclei of TiC. In the case of Al2O3 dust, chemical equilibrium indicates that atomic Al and the carriers of Al-O bonds AlOH, AlO, and Al2O are the most likely gas-phase precursors.

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Bale, C. W., E. Bélisle, P. Chartrand, et al. "FactSage thermochemical software and databases — recent developments." Calphad 33, no. 2 (2009): 295–311. http://dx.doi.org/10.1016/j.calphad.2008.09.009.

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