Salt Components Research Articles

Response of soil water, salt, carbon and bacteria community to terrain and plant in coastal salt marsh

Terrain and plants play a crucial role in influencing or regulating the variations of water, salt, carbon, and bacteria community in the soil of coastal salt marshes. Investigating these variations and their interconnections under different conditions is essential to comprehensively understand the carbon sequestration function and reveal the underlying mechanisms of carbon sinks in coastal salt marshes. In this study, the various physicochemical properties of rhizosphere and non-rhizosphere soil under different terrain of coastal salt marsh in Jiaozhou Bay were determined. Additionally, the contents of soil carbon components including soil inorganic carbon (SIC), soil organic carbon (SOC), dissolved inorganic carbon (DIC), and dissolved organic carbon (DOC), and constituents of soil dissolved organic matter (DOM) and microbial community were analyzed. The results showed that the contents of SIC and SOC in high-terrain soil were significantly lower than those in low-terrain soil (P < 0.05). Plants could regulate the physicochemical properties, and carbon components of soil in different terrain, resulting in no significant difference in SOC contents of rhizosphere soil under different terrain. Soil DOM composition and bacterial community showed that high-terrain soil had higher bacterial diversity and activity, and plants significantly affected the bacterial community structure in soil through rhizosphere effects. The structural equation model demonstrated that terrain has an indirect impact on SOC through influencing on the fluorescence of soil DOM and bacterial diversity, and SIC through altering soil water content (SWC), electrical conductivity and DOC. Plants directly or indirectly affected SOC content, and indirectly affected SIC content by changing SWC. This study contributes to a better understanding of the complex interactions between wetland ecosystems and their soil water, salt, carbon, and bacteria community components, offering valuable information for wetland management and conservation efforts.

Effects of sodium chloride on mechanical properties in amorphous polymers of waterlogged archaeological wood: Insights from molecular dynamics simulations

Sodium chloride (NaCl) is the main soluble salt component of marine waterlogged archaeological wood, and it causes deterioration of wood fibres. In this study, a molecular dynamics simulation of three types of archaeological wood from the Quanzhou Song Shipwreck was employed to investigate the impact of NaCl on the mechanical properties of amorphous components consisting of amorphous cellulose, hemicellulose, and lignin. The findings revealed that water molecules bound to the fibres enhanced the mechanical performance of the woody fibres. However, NaCl affected the stability and mechanical properties of the amorphous components. By using molecular dynamics simulations, 24 sets of amorphous fibre models, consisting of fir, pine, and camphorwood with salt concentrations ranging from 0 % to 7 %, were constructed to further analyse the influence of salt content on the mechanical properties of the amorphous components. The results showed that all three species of archaeological wood exhibited similar trends, with the adsorption energy and radial distribution function between wood fibres and water molecules decreasing with increasing NaCl concentration, leading to the gradual rupture of hydrogen bonds in water molecules. Consequently, more water molecules engage in ion hydration, resulting in an increase in the amount of free water within the amorphous regions. This, in turn, degrades the mechanical properties of the amorphous components. This study contributes significantly to a comprehensive understanding of the mechanical properties of marine archaeological wood and is important for decision-making in studies related to the preservation and evaluation of marine waterlogged wooden artefacts.

Supramolecular "baking powder": a hexameric halogen-bonded phosphonium salt cage encapsulates and functionalises small-molecule carbonyl compounds.

We report a hexameric supramolecular cage assembled from the components of a Wittig-type phosphonium salt, held together by charge-assisted halogen bonds. The cage reliably encapsulates small polar molecules, including aldehydes and ketones, to provide host-guest systems where components are pre-formulated in a near-ideal stoichiometry for a mechanochemical base-activated Wittig olefination. These pre-formulated solids represent a proof-of-principle for a previously not reported supramolecular design of solid-state reactivity in which the host for molecular inclusion also acts as a complementary reagent for the subsequent chemical transformation of an array of guests. The host-guest solid-state complexes can act as supramolecular surrogates to their Wittig olefination vinylbromide products in a Sonogashira-type coupling that enables one-pot mechanochemical conversion of an aldehyde to an enediyne.

Effect of the Anionic Component of Cadmium Salt on the Morphology, Composition, and Topological Features of CdS–PbS Nanocrystalline Films

Effect of the Anionic Component of Cadmium Salt on the Morphology, Composition, and Topological Features of CdS–PbS Nanocrystalline Films

Proanthocyanidins from Chinese Bayberry (Myrica rubra Sieb. et Zucc.) Leaves Effectively Inhibit the Formation of Biogenic Amines in the Brewing Soy Sauce

Biogenic amines are a group of metabolites generated in the process of soy sauce brewing, which can result in severe negative impacts on human health at high concentrations. In this study, we innovatively proposed natural extracts (0.1 wt%), of proanthocyanidins, from Chinese bayberry (Myrica rubra Sieb. et Zucc.) leaves to alternate commercial additives (0.1 wt%), i.e., sodium benzoate and potassium sorbate, for lowering the harmful biogenic amine formation during the fermentation of soy sauce. HPLC results showed that natural extracts from Chinese bayberry leaves could effectively decrease the content of cadaverine, putrescine, histamine, tyramine, phenylethylamine, and agmatine (p &lt; 0.05). In contrast to the inhibitory influence exhibited by commercial sodium benzoate and potassium sorbate, extracts from bayberry leaves can maintain spermidine, spermine, and tryptamine at certain concentrations. Furthermore, both sodium benzoate and potassium sorbate significantly reduced the production of ammonium salt and characteristic components (p &lt; 0.05), like soluble saltless solids, total nitrogen, and amino acid nitrogen, during the 40-day fermentation of soy sauce, whereas proanthocyanidins extracted from Chinese bayberry leaves slightly inhibited the content of ammonium salt. Thus, we can conclude that, while inhibiting the biogenic amine and ammonium salt production, extracts from Chinese bayberry leaves facilitate or maintain the production of characteristic indicators compared to commercial sodium benzoate and potassium sorbate. Taken together, natural extracts from Chinese bayberry leaves can be considered a natural additive to significantly improve the quality of traditional brewing soy sauce.

Diffusion analysis of three kinds of species with two salts in two working fluids using Darcy's law using solar radiations

This specific research was carried out with the aim of investigating incompressible Casson fluid and Williamson liquid. Steady-state laminar boundary layer flow involving Brownian diffusion and thermophoretic diffusion is taken over a horizontal penetrating plate saturated with two distinct salts having distinct characteristics. Casson fluid motion was observed with the utilization of Darcy-Forchheimer technique. Whilst, Nanofluid motion and other salts motion induced by wall movement. Solar thermal collectors, Solar thermal systems, Solar cookers, Solar thermal energy, drying, generating electricity, chemical reactions, soil vapor extraction, medication and heat exchange medium. Physical quantities like density, temperature profile and concentration profile were addressed by aiding Bossiness approximation. Whereas the optimization of energy is carried out under the effects of cross-diffusion, regular diffusion and non-Fourier law for two different salt components. Formulation of acquired flow equations in terms of partial differential equations are further transformed into ordinary differential equations using similarity transformations. The numerical solution will be obtained by utilization of FE-method. It was found that the temperature field elevates on increasing solar thermal radiation number, modified Dufour numbers of salt 1 and salt 2. Thickness and width regarding momentum layers for Casson liquid rather than Williamson liquid while temperature field for Williamson liquid is higher than Casson liquid.

Seasonal differences in continental outflows and marine emissions of organic aerosols in the East China Sea: Insight from the variation of saccharides

Water-soluble organic species play an important role in cloud condensation nuclei and cloud formation in marine atmosphere. The present study investigated the influence of continental outflows and marine biogenic emission on organic aerosol in the East China Sea from the perspective of saccharides during a cold season and a warm season in 2019, respectively. Driven by the East Asian continental outflows during the cold season, levoglucosan emitted from biomass burning were the dominant species and were mostly concentrated in fine mode (<2.5 μm). Biogenic species, including primary sugars and sugar alcohols, were the dominant species in warm season, accounting for a high fraction of WSOC with 5.48 ± 3.29%, and were mostly distributed in coarse mode (2.5–10 μm). This trend was consistent with sea salt components (Na+ and Cl−) when air masses originated from oceanic areas, suggesting that marine emissions could be the major sources of saccharides during the warm season. Particularly, a dramatic increase in biogenic saccharides (glucose, sucrose, mannitol and arabitol) was observed when experienced the “Super Typhoon Lekima”. Concentrations of these species were 2 to 5 times higher than that in normal days, illustrating the significant impact of extreme weather events on the emissions of biogenic aerosols in marine area. This study improves the understanding of combined impacts of continental outflows and marine emissions on water-soluble organic species in the East China Sea, again highlighting the important contribution of marine biogenic emissions under extreme weather conditions.

Structural regulation chemistry of lithium-ion solvation in nonflammable phosphate-based electrolytes for high interfacial compatibility with graphite anode

With the booming development of lithium-ion batteries, safety has become one of the most primary focuses of current researches. Although there are various approaches to enhance the safety of lithium-ion batteries, phosphate-based electrolyte holds the greatest potential for practical application due to their non-flammability. Nonetheless, its compatibility issue with the graphite anode remains a significant obstacle to its widespread use. Herein, an effective method is proposed to improve the compatibility of electrolyte with graphite (Gr) anode by rationally adjusting the proportion of lithium salt and solvent components to optimize the Li+ solvation structure. By slightly increasing the Li+/triethyl phosphate (TEP) ratio, TEP alone cannot fully occupy the inner solvation sheath and therefore less polar ethylene carbonate (EC) has to be recruited, and the solvation structure gradually changes from Li+–[TEP]4 to Li+–[TEP]3[EC] with the coexistence of EC and TEP. Simultaneously, EC molecules in the Li+–[TEP]3[EC] could be preferentially reduced on graphite compared to the TEP molecules, resulting in the formation of a uniform and durable solid-electrolyte interphase (SEI) layer. Benefiting from the optimized phosphate-based electrolyte, the Gr|Li battery exhibits a capacity retention rate of 96.8% after stable cycling at 0.5 C for 470 cycles which shows a longer cycle life than the battery with carbonate electrolyte (cycling at 0.5 C for 450 cycles). Therefore, this work provides the guidance for designing a non-flammable phosphate-based electrolyte for high-safety and long cycling-life lithium-ion batteries.

Supramolecular and double network strategy toward strong and antibacterial protein films by introducing waterborne polyurethane and quaternized chitosan

Plant-derived protein composite film is one of the promising substitutes for non-renewable petroleum-based materials. However, its application is greatly limited due to the low mechanical strength and poor antibacterial activity. In this paper, a dual network strategy based on supramolecular chemistry was reported for fabricating a high-strength and antibacterial soybean protein (SP)-based biofilm by incorporating waterborne polyurethane (WP) and quaternized chitosan (QCS). Specifically, castor oil as a renewable plant resource was used for the preparation of functional WP polymer. Based on the synergistic effect of WP network and SP network, the performance of SP-based composite film was significantly enhanced. Compared with the original SP film, the tensile strength and toughness of SP/WP/QCS film were substantially increased by 159% and 531%, respectively. In addition, the composite film showed significantly enhanced water resistance and UV shielding capability. Due to the antibacterial effect of the quaternary ammonium salt component, the SP/WP/QCS composite film exhibited superior antibacterial properties. Therefore, this study provides a feasible strategy for the preparation of high-performance SP-based films, which is expected to be applied in packaging, multifunctional adhesive, and UV-shielding coating.

A novel approach to modify Stenotrophomonas sp. D6 by regulating the salt composition in the growth medium: Enhanced removal performance of Cr(VI)

In this study, a novel and effective modified microbial reducing agent was developed to detoxify Cr(VI) from aqueous solutions. This was achieved by carefully controlling specific salt components in the growth medium. Based on the single-salt modification, several effective modified salts were selected and added to the medium for synergistic modification. The results showed that the synergistic modification with NH4Cl and KH2PO4 had the best detoxification effect on Cr(VI), reaching 98.5% at 100 mg/L Cr(VI), which was much higher than the 43.7% of the control (original Luria-Bertani medium). This enhancement was ascribed to the ability of NH4Cl and KH2PO4 to stimulate the growth of Stenotrophomonas sp. D6 promoted chromate reductase secretion. The protein content of the modified medium supernatant was significantly increased by 10.76% compared to that before modification. Based on the micro-characterization, the main process for the elimination of Cr(VI) is microbial reduction rather than biosorption. Most of the reduced Cr was found in the extracellular suspension, thereby suggesting that the primary reduction occurred outside the cells, whereas only a small fraction was detected intracellularly. Overall, this study provides a simple and effective method for microbial treatment of heavy metals in aqueous solutions.

Promotion of Salinity to Protonation of Amidine-based CO2-switchable Surfactant

Amidine-based switchable surfactants, whose surface activity is enabled by protonation, are a desirable candidate for the development of enhanced oil recovery methods. However, studies on the influence of salt components on the protonation of amidine-based surfactants are still very limited. In this study, it has been found that inorganic salts can induce the protonation of amidine-based surfactants, using N’-dodecyl-N and N-dimethyl acetamidine (C12-DMAA) as an example. The feasibility predictions of protonation of C12-DMAA in pure water and brines were attained by quantum chemical simulation. The occurrence of partial protonation is determined by Nuclear Magnetic Resonance (NMR). In the dispersion test, variation in conductivity and pH indicated that the water molecule plays the role of proton donor in the protonation process, and the protonation level is unaffected by the presence of cationic species. Overall, this research enhances the understanding of the switchable ability, as well as the efficient utilization of amidine-based surfactants in salt-containing systems.

THE RELEVANCE OF RESEARCH THE PROGRESS ON THE APPLICATION OF MUSHROOM IN MEAT PRODUCTS PROCESSING

In this article, the function of mushrooms and the progress of their application in meat processing were introduced. According to the last research, some types of meat products contain more saturated fatty acids, cholesterol, sodium salt, phosphate, nitrite and other components, and excessive intake of these components may lead to obesity, cardiovascular disease, cancer and a series of diseases. So, the food industry is redesigning existing products or developing new ones that are healthier and more sustainable, and shifting to focus on the application of plant ingredients. Attention is drawn to the fact that more and more studies have been conducted to improve the nutritional and functional properties of food by adding vegetables, beans, cereals, tubers, edible seeds, algae or insects as substitutes for fat, protein and salt. Mushrooms has attracted much attention because of its high nutritional value, wide variety of bioactive compounds, antioxidant effect and health function, and excellent flavor and taste, mushroom can provide exogenous active substances for meat products and improve the nutritional value and functional properties of meat products. The application progress and development prospect of mushroom as fat substitute, protein substitute, salt, phosphate and nitrite substitute, flavor additive and antioxidant in meat products were analyzed. There is a lack of research on the health function of mushroom in meat products, and the potential effects and mechanisms of mushroom applied to meat products on human health and health function need to be further explored in the future. The results showed that the application of mushrooms in meat processing meets people’s requirements for green, healthy and functional food industry. Mushrooms are a promising functional additive in meat processing.

Understanding Solid Electrolyte Interphase (SEI) Species at the Electrode-Electrolyte Interface in Liquid Lithium Metal Batteries Via in-Situ Fourier Transform Infrared (FTIR) Spectroscopy

Lithium metal is the ideal candidate to replace conventional carbonaceous anodes due to its high theoretical specific capacity of 3860 mAh/g and low negative thermodynamic potential of -3.040 V vs. SHE [1]. Fine tuning the solid-electrolyte interphase (SEI) is critical for the practical implementation of liquid lithium metal batteries [2]. The presence of particular SEI species are hypothesized to improve the coulombic efficiency and mitigate dendrite formation for enhanced lifetime and safety, respectively [2]. Recently, Zhang et al. developed a novel in-situ Fourier transform infrared (FTIR) spectroscopy method to reveal electrolyte oxidation via carbonate dehydrogenation on Ni-based oxides in Li-ion batteries [3]. We leverage this technique and apply it to the Cu side in a Li || Cu battery to probe SEI growth and evolution. In this study, we systematically change the salt, solvent and additive components of the electrolyte and monitor the organic and inorganic SEI species that form under different electrochemical conditions. Furthermore, we directly correlate the chemical composition of the SEI to cell-level coulombic efficiency [4]. Complimentary characterization techniques will be used to further resolve the chemical structure of the SEI. Finally, results from this study will help generate descriptors for the rationale design of new electrolytes.

Electrochemical separation of Fe and Ti from ilmenite via molten salt electrolysis and its mechanism

A green separation routes for Fe and Ti from ilmenite via molten salt electrolysis is proposed in CaCl2-NaCl-CaO molten salt. FeTiO3 powder can be dissolved into the molten salt, directly. In the process, CaTiO3 is formed by the reaction of TiO32- and Ca2+ in molten salt components. Pure iron is obtained under the controllable regulation of electrolysis parameters such as cell voltage or electrolysis temperature. Fe is deposited on the cathode by the selective electroreduction of Fe2+ with 2 electrons transfer process. Ti through the consecutive two-steps with 4 electrons transfer electroreduction process of TiO32- is obtained: TiO32- → TiO →Ti. FeTi and Fe2Ti alloy is also obtained through reaction of Fe and Ti. The electroreduction of Fe2+ and TiO32- is limited by its diffusion. This approach provides a one-step green and sustainable separation of Fe and Ti from ilmenite (FeTiO3). The main product of Fe and CaTiO3 can be used for the field of catalyst, architecture, aerospace and energy storage materials.

Transient melt formation and its effect on conversion phenomena during nuclear waste vitrification – HT‐ESEM analysis

AbstractAlthough the vitrification of nuclear waste has a decades‐long history, numerous opportunities still exist to improve its efficiency and to increase the waste loading in glass. This is especially true for the vitrification of low‐activity waste (LAW), which has been historically treated by other immobilization technologies and is less mature than high‐level waste (HLW) vitrification. In this work, we address one of the least understood phenomena during the conversion of nuclear waste feeds to glass—the formation of molten salt and transient glass‐forming melt. Using high‐temperature environmental scanning electron microscopy (HT‐ESEM) in combination with X‐ray diffraction, thermogravimetry, and evolved gas analysis, we have analyzed the complex chemical reactions and phase transitions as they occur during melting of representative HLW and LAW melter feeds. We evaluated the compositions of amorphous phases and the fractions of salt components, and estimated the fractions of molten salt phases present in the feeds as a function of temperature. We show that the maximum fraction of molten salts is ∼4 % and ∼28 % during HLW and LAW feed melting, respectively, and discuss the possibility of molten salt migration in LAW feeds. We also argue that the presence of significant fractions of molten salt phase can hinder the retention of rhenium (and, hence, radioactive technetium), and discuss how the properties of molten salt phase and transient glass‐forming melt are related to primary foam formation and behavior. Finally, we summarize key unanswered questions requiring further research to increase the understanding of the conversion process and enhance the nuclear waste vitrification efficiency.

Capturing CO2 by ionic liquids and deep eutectic solvents: A comparative study based on multi-level absorbent screening

Because of the high energy consumption and volatility of organic amine solvents in conventional CO2 capture processes, ionic liquids (ILs) and deep eutectic solvents (DESs) have been widely expected as alternative CO2 absorbents. In this work, promising ILs and DESs are identified through a comparative, multi-level absorbent screening method proposed for the first time from a large space of cation–anion combinations and potential DES components, respectively. Important physical properties (namely melting point, viscosity, and toxicity) of potential ILs and salt components of DESs are estimated by a recently-reported deep learning model. Key thermodynamic properties including physically-based absorption and desorption potentials as well as eutectic behaviors between DES component combinations are predicted by the COSMO-RS model. Five EHS (environment, health, and safety) related properties of non-salt components of DESs are assessed by the VEGA platform. From above, the top three ILs and DESs are identified from 5,440 and 38,389 candidates, respectively. The CO2 capture processes based on the retained ILs and DESs are simulated in Aspen Plus in rate-based mode, identifying 1-methyl-1-propylpyrrolidinium bromide: methylimidazole (1:2) as the absorbent with the highest process performance. The experiments shows that the molality-based Henry constant of CO2 in DES is as low as 1.32, validating the competitive absorption performance of this potential DES. Finally, quantum chemistry calculations are conducted to unveil the microscopic absorption mechanism of this DES.

HAEMATURIA DETECTABLE IN OUTPATIENT CHILDREN AND TEENAGERS: THE FREQUENCY AND POSSIBLE REASONS

Determining the cause of haematuria in children often causes significant difficulties, especially for outpatients, due to the large number of diseases with increased quantity of red blood cells in urine and complexity of such patients examination.&#x0D; The frequency and features of haematuria have been defined in outpatient children and teenagers. The frequency of haematuria in 2018-2021 was on average 4,5 %, increasing significantly from 2,4 % in 2018 to 8,3 % in 2021. The most cases of haematuria after a hot summer can relate to increased concentration of salt components in urine due to insufficient drinking intake. Haematuria identified in outpatient children was not a manifestation of severe diseases with poor prognosis (tumors, tuberculosis). It was small, transient, and disappeared in most patients after increased fluid intake, nutrition and physical activity correction, antibacterial medicines and phytotherapy appointment in urinary tract infection

Thermodynamic Model of the Fluid System H2O–CO2–NaCl–CaCl2 at P-T Parameters of the Middle and Lower Crust

Based on the earlier obtained equations of state for the ternary systems H2O–CO2–CaCl2 and H2O–CO2–NaCl, an equation of state for the four-component fluid system H2O–CO2–NaCl–CaCl2 is derived in terms of the Gibbs excess free energy. A corresponding numerical thermodynamic model is built. The main part of the numerical parameters of the model coincides with the corresponding parameters of the ternary systems. The NaCl–CaCl2 interaction parameter was obtained from the experimental liquidus of the salt mixture. Similar to the thermodynamic models for H2O–CO2–CaCl2 and H2O–CO2–NaCl, the range of applicability of the model is pressure 1–20 kbar and temperature from 500 to 1400°C. The model makes it possible to predict the physicochemical properties of the fluid involved in most processes of deep petrogenesis: the phase state of the system (homogeneous or multiphase fluid, presence or absence of solid salts), chemical activities of the components, densities of the fluid phases, and concentrations of the components in the coexisting phases. The model was used for a detailed study of the phase state and activity of water on the H2O–CO2–salt sections when changing the ratio {{{{x}_{{{text{NaCl}}}}}} mathord{left/ {vphantom {{{{x}_{{{text{NaCl}}}}}} {({{x}_{{{text{NaCl}}}}} + {{x}_{{{text{CaC}}{{{text{l}}}_{{text{2}}}}}}})}}} right. kern-0em} {({{x}_{{{text{NaCl}}}}} + {{x}_{{{text{CaC}}{{{text{l}}}_{{text{2}}}}}}})}} from 1 to 0. Changes in the composition and density of coexisting fluid phases at a constant activity of water and changes in the total composition of the system are studied. A set of phase diagrams on sections H2O–NaCl–CaCl2 for different mole fractions of CO2 is obtained. Pressure dependencies of the maximal activity of water in the field of coexisting unmixable fluid phases are obtained for several salt compositions of the system. Due to removal of restrictions resulting from a smaller number of components in ternary systems, the thermodynamic behavior of systems with a mixed composition of the salt significantly differs from the behavior of those with a single salt component.

Extending UNIFAC models for solid-liquid equilibria prediction and design of eutectic solvent systems

Although eutectic solvents (ESs) have received considerable attention as sustainable process fluids for various applications, discovering novel ESs remains challenging as computational methods for predicting the formation of eutectics are still scarce. In the present work, both the original and modified UNIFAC models are evaluated and extended for predicting the solid–liquid equilibria (SLE) of ES systems. The applicability of the two versions of UNIFAC models is first evaluated based on the SLE of 25 ES systems composed of only conventional components. Motivated by the good evaluation results, the SLE of 50 ES systems involving one salt component are employed to extend the UNIFAC models to include novel salt-component-related functional groups. The obtained models cover widely-reported salt components of choline/tetraalkylammonium chloride/bromide and conventional components of fatty alcohols and fatty/dicarboxylic/α-hydroxy acids. A theoretical design of novel ESs in a large scale is performed with the best-performing model extension, wherein four designed ES systems are validated experimentally.

Thermodynamic Model of the Fluid System H&lt;sub&gt;2&lt;/sub&gt;O–CO&lt;sub&gt;2&lt;/sub&gt;–NaCl–CaCl&lt;sub&gt;2&lt;/sub&gt; at &lt;i&gt;P-T&lt;/i&gt; Parameters of the Middle and Lower Crust

Based on the earlier obtained equations of state for the ternary systems H2O–CO2–CaCl2 and H2O–CO2–NaCl, an equation of state for the four-component fluid system H2O–CO2–NaCl–CaCl2 is derived in terms of the Gibbs excess free energy. A corresponding numerical thermodynamic model is build. The main part of the numerical parameters of the model coincides with the corresponding parameters of the ternary systems. The NaCl–CaCl2 interaction parameter was obtained from the experimental liquidus of the salt mixture. Similar to the thermodynamic models for H2O–CO2–CaCl2 and H2O–CO2–NaCl, the range of applicability of the model is pressure 1–20 kbar and temperature from 500°C to 1400°C. The model makes it possible to predict the physicochemical properties of the fluid involved in most processes of deep petrogenesis: the phase state of the system (homogeneous or multiphase fluid, presence or absence of solid salts), chemical activities of the components, densities of the fluid phases, and concentrations of the components in the coexisting phases. The model was used for a detailed study of the phase state and activity of water on the H2O–CO2–salt sections when changing the ratio \( {{{{x}_{{{\text{NaCl}}}}}} \mathord{\left/ {\vphantom {{{{x}_{{{\text{NaCl}}}}}} {\left( {{{x}_{{{\text{NaCl}}}}} + {{x}_{{{\text{CaC}}{{{\text{l}}}_{{\text{2}}}}}}}} \right)}}} \right.} {\left( {{{x}_{{{\text{NaCl}}}}} + {{x}_{{{\text{CaC}}{{{\text{l}}}_{{\text{2}}}}}}}} \right)}} \) from 1 to 0. Changes in the composition and density of coexisting fluid phases at a constant activity of water and changes in the total composition of the system are studied. A set of phase diagrams on sections H2O–NaCl–CaCl2 for different mole fractions of CO2 is obtained. Pressure dependencies of the maximal activity of water in the field of coexisting unmixable fluid phases are obtained for several salt compositions of the system. Due to removal of restrictions resulting from a smaller number of components in ternary systems, the thermodynamic behavior of systems with a mixed composition of the salt is significantly differ from the behavior of those with a single salt component.