Multicomponent Mixtures Research Articles

Effect of hydrogen addition on the consumption speed of lean premixed laminar methane flames exposed to combined strain and heat loss

This study presents a numerical analysis of the impact of hydrogen addition on the consumption speed of premixed lean methane-air laminar flames exposed to combined strain and heat loss. Equivalence ratios of 0.9, 0.7, and 0.5 with fuel mixture composition ranging from pure methane to pure hydrogen are considered to cover a wide range of conditions in the lean region. The 1-D asymmetric counter-flow premixed laminar flame (aCFPF) with heat loss on the product side is considered as a flamelet configuration that represents an elementary unit of a turbulent flame and the consumption speed is used to characterise the effect of strain and heat loss. Due to the ambiguity in the definition of the consumption speed of multi-component mixtures, two definitions are compared. The first definition is based on a weighted combination of the consumption rate of the fuel species and the second one is based in the global heat release rate. The definition of the consumption speed based on the heat release results in lower values of the stretched flame speed and even an opposite response to strain rate for some methane-hydrogen-air mixtures compared to the definition based on the fuel consumption. Strain rate leads to an increase of the flame speed for the lean methane-hydrogen mixtures, reaching a maximum value after which the flame speed decreases with strain rate. Heat loss decreases the stretched flame speed and leads to a sooner extinction of the flamelet due to combined strain and heat loss. Hydrogen addition and equivalence ratio significantly impact the maximum consumption speed and the flame response to combined strain rate and heat loss. The effect of hydrogen on the thermo-diffusive properties of the mixture, characterised by the Zeldovich number and the effective Lewis number, are also analyzed and related to the effect on the consumption speed. Two definitions of the Lewis number of the multi-component fuel mixture are evaluated against the results from the aCFPF.

Triboelectric Mechanism of Oil-Solid Interface Adopted for Self-Powered Insulating Oil Condition Monitoring.

The liquid-solid contact electrification mechanism has been explored in the aqueous solution system, but there are few systematic studies on oil-solid triboelectrification. Herein, an oil droplet triboelectric nanogenerator (Oil-droplet TENG) is designed as the probe to investigate the charge transfer properties at oil-solid interface. The charge transfer kinetics process is disclosed by the electrical signals produced, showing that the electron species initially predominated the oil-solid triboelectrification. The molecular structure and electronic properties of oil also affect triboelectric performance. Further, the charge transfer principle in multi-component liquid mixture during the electric double layer (EDL) development process is proposed to explain the component competition effect. As a proof of concept, a tubular-TENG is designed as a self-powered sensor for transformer oil trace water detection. The device demonstrates high water sensitivity with a detection limit of 10µL L-1 and a response range of 10-100µL L-1 . This work not only reveals the oil-solid triboelectric and charge transfer competition mechanism in EDL, but also open up a new channel for real-time online monitoring of trace water in transformer oil, which holds promise for information perception and intelligent operation of transformers in the power industry.

Separation of Methanolic Leaf Extracts of Three Rutaceous Plants by Capillary Electrophoresis and High-Performance Liquid Chromatography Methods

Pharmacognosy Research,2023,15,2,392-398.DOI:10.5530/pres.15.2.042Published:February 2023Type:Original Article Authors:Chakravarthi Guntupalli, Narender Malothu, Ankarao Areti, Buchi N Nalluri, Praveen Sivadasu, and Narayanarao Alla Author(s) affiliations:Chakravarthi Guntupalli*, Narender Malothu, Ankarao Areti, Buchi N Nalluri, Praveen Sivadasu, Narayanarao Alla K L College of Pharmacy, Koneru Lakshmaiah Education Foundation, Vaddeswaram, Guntur, Andhra Pradesh, INDIA. Abstract:Introduction: In the phytochemical analysis of various multi component mixtures, Capillary electrophoresis (CE) method was considered as the best alternative tool due to high efficiency resolution separations, low solvent consumption and less maintenance costs. Materials and Methods: This study uses CE and high-performance liquid chromatography (HPLC) methods to evaluate the major components of methanolic leaf extract of Rutaceous plants. And also, to assess the purity of the components in isolated fractions and most importantly for the qualitative identification of the individual components of extracts based upon the relative retention time and UV profile. Results: The separation of the compounds in HPLC was attained by using ACE-5-C18 (250 x 4.6 mm) with a flow rate of 1.5 ml/min, with the UV detection at 254 nm and CE was equipped with a UV diode-array detector and bare, fused silica capillaries (56 cm 50 μm) with micro extended light path were used for the separations. Conclusion: Our study reveals that CE technique is a simple, economical and convenient method and shown high-resolution for multi-components found in plant extracts compared with HPLC profiles. Keywords:Capillary Electrophoresis, HPLC, Relative Retention Time, Rutaceae.View:PDF (425.61 KB)

Gas mixtures IR absorption spectra decomposition using a deep neural network

An approach to multicomponent gas mixtures IR absorption spectra decomposition using a deep neural network was developed. The process of refinement and optimization of the absorption spectra data model to improve the accuracy of the inverse spectroscopic task solution is described. A criterion for the reliability of restoring the concentration of an individual component in a gas mixture based on its share of the area under the absorption spectrum curve was suggested and tested.

The Problem of Utilization of Liquefied Natural Gas Vapor at Large-scale LNG Plants

The liquefied natural gas (LNG) is stored under low overpressure in a saturated state in large-capacity tanks with multilayer thermal insulation. Owing to the input of heat from the environment through thermal insulation, LNG is continuously evaporated. Since natural gas is a multicomponent mixture, LNG vapors are enriched with its low-boiling components, then the supply of heat from the environment reduces the amount of liquid in the reservoir and changes its chemical composition. Similar phenomena occur during LNG transportation. The present paper deals with the problem of LNG vapor utilization during its storage and transportation. Information is presented on the causes of the LNG vapor formation (boil-off gas) and methods for its disposal during storage and transportation to consumers. A numerical experiment was performed based on the data of LNG storage in large-capacity storage facilities at the Yamal LNG plant. The technique consists of the estimation of material flows toward the system of accumulation and extradition of LNG. The results show that the vapor flow generated from the inflow of new LNG portions into the storage significantly exceeds that generated from the heat supply from the environment.

Analysis of energy characteristics of vibration mixing of multicomponent mixtures of agricultural raw materials

Ensuring the efficiency of the use of nutrients of grain, protein, vitamin and mineral feeds in the composition of complete feed mixtures in animal husbandry and crop production, as well as the corresponding reduction in the cost of manufacturing of these products, is the relevance of the presented research and prospects for their development. Therefore, the purpose of the study is to substantiate the effective regime parameters for the preparation of premixes of feed mixtures based on the assessment of the energy parameters of the vibration mixing process. This assessment was carried out by comparing the results of applying vibration, blade, and vibroblade technological operations. Under the conditions of low-frequency vibrations, a decrease in the working resistance of the loosened layer of the mixture is observed, which provided the effect of reducing energy consumption in this process. Therefore, in comparison with conventional vibrating mixers have a higher specific productivity of 5-6 times, provide a reduction in the mixing time by 2-3 times, metal consumption – by 17%, energy consumption – by 30%, capital costs for manufacturing – by 18%, and drive power – by 30-35%, which leads to a reduction in total energy consumption by 3-4 times. As a result, the zone of minimal energy consumption was substantiated, in which the reduction of the resistance of the technological medium allowed radically reducing the friction forces during mixing, while ensuring uniform distribution with the concentration of the components of the mixture required by technological requirements. An increase in the oscillation amplitude is accompanied by a quadratic increase in power consumption, which is conditioned by an increase in energy dissipation in the mass of the mixture in the form of heat. The implementation of reasonable operating mixing modes allowed reducing the energy consumption of the proposed vibro-blade mixing by 2.0-2.5 times compared to conventional blade processing. The practical value of these developments includes the use of vibro-blade working bodies and the vibration-free operation of the drive shaft, which, together with the minimisation of energy consumption for the process, reduces dynamic loads on the support units of the developed mixer

Separation of volatile organic contaminants from water using a direct-contact dehumidifier: An experimental study and modeling

A packed-bed, direct-contact dehumidifier (PB-DCD) has been developed to selectively condense water from a gaseous mixture of organic contaminants. In this process, hot air is humidified by mixing with wastewater vapor in a static mixer and is dehumidified by subcooled fresh water passing through the PB-DCD in a counter-current configuration. The goal of this study is to understand the relationship between various operating parameters and how they affect separation of isopropyl alcohol (IPA) from the gaseous mixture with the purpose of expanding the investigation to other contaminants in the future. The process has been successfully used to separate IPA from wastewater. Different parameters including the concentration of IPA in water, feed temperature, air-to-vapor ratio, and cooling-water-to-vapor mass ratio, as well as residence time were examined to determine their influence on contaminant separation and clean water recovery rate. The Buckingham Pi theorem was applied to reduce the number of studying variables by generating non-dimensional groups. Experiments were performed to determine the relationship between the non-dimensional parameters and model mass transfer in the system. Mass transfer coefficients for multicomponent gaseous mixture condensation in a packed-bed direct contact condenser column are calculated and a modified correlation of mass transfer is developed. The parameters of the mass transfer model are obtained from operating conditions of the PB-DCD, stream conditions and thermodynamic properties. A modified Sherwood correlation is developed to predict IPA separation from a gaseous mixture consisting of air, water, and IPA. The modified Sherwood correlation is applied to successfully predict the Sherwood number with a mean absolute error equal to 6.6 %. According to the experimental results, the maximum IPA separation achieved was 76.3 %, which corresponds to a water recovery rate of 58.7 %.

Distribution of cholesterol in asymmetric membranes driven by composition and differential stress.

Phospholipid asymmetry appears to be an evolutionarily conserved property of eukaryotic plasma membranes, suggesting it is crucial for their structure and function. It is fundamentally a non-equilibrium phenomenon since it can decay by lipids ‘‘flip-flopping’’ between leaflets. Cells must therefore maintain it by a variety of active mechanisms. This is easy for regular phospholipids, whose flip-flop takes hours/days but difficult for cholesterol, where these timescales are in the microsecond range. Cholesterol affects many properties of lipid membranes, from their elastic response to emergence of rafts in multi-component mixtures. It is therefore distressing that we know so little about its trans-membrane partitioning. We propose a theoretical model for the distribution of cholesterol in asymmetric membranes, focusing on the interplay of two dominant effects-difference in lipid composition, which leads to a partitioning bias in cholesterol, and lateral stress arising from crowding one leaflet with respect to the other. To test our theory, we employed coarse grained molecular dynamics simulations performed using the Cooke model. We find that our theory, which accounts for various elastic and thermodynamic drivers, explains the trends in our simulations. We show that the presence of cholesterol does not automatically result in tensionless membranes, even in the absence of preferential partitioning of this species. Additionally, we find that cholesterol's solvation bias can balance phospholipid number asymmetry, which results in strong correlations between cholesterol asymmetry and differential stress. Applying our theory to the most recent data on human RBC membranes suggests that close to 90% of all cholesterol resides in the exoplasmic leaflet, with a large remaining differential stress. This calls into question the notion of rafts being exoplasmic domains connected to liquid-ordered/liquid-disordered phase coexistence and forces us to rethink the common textbook picture of plasma membranes.

Continuum Models for Bulk Viscosity and Relaxation in Polyatomic Gases

Bulk viscosity and acoustic wave propagation in polyatomic gases and their mixtures are studied in the frame of one-temperature and multi-temperature continuum models developed using the generalized Chapman–Enskog method. Governing equations and constitutive relations for both models are written, and the dispersion equations are derived. In the vibrationally nonequilibrium multi-component gas mixture, wave attenuation mechanisms include viscosity, thermal conductivity, bulk viscosity, diffusion, thermal diffusion, and vibrational relaxation; in the proposed approach these mechanisms are fully coupled contrarily to commonly used models based on the separation of classical Stokes–Kirchhoff attenuation and relaxation. Contributions of rotational and vibrational modes to the bulk viscosity coefficient are evaluated. In the one-temperature approach, artificial separation of rotational and vibrational modes causes great overestimation of bulk viscosity whereas using the effective internal energy relaxation time yields good agreement with experimental data and molecular-dynamic simulations. In the multi-temperature approach, the bulk viscosity is specified only by rotational modes. The developed two-temperature model provides excellent agreement of theoretical and experimental attenuation coefficients in polyatomic gases; both the location and the value of its maximum are predicted correctly. One-temperature dispersion relations do not reproduce the non-monotonic behavior of the attenuation coefficient; large bulk viscosity improves its accuracy only in the very limited frequency range. It is emphasized that implementing large bulk viscosity in the one-temperature Navier–Stokes–Fourier equations may lead to unphysical results.

Particle force-based density segregation theory for multi-component granular mixtures in a periodic chute flow

Density segregation of multi-component granular mixtures in a dense, gravity-driven flow over a rough and bumpy periodic chute surface is studied using theory and simulations. An existing theoretical model for predicting the steady-state concentration field of each species in a binary mixture using the forces acting on the particles is generalised for multi-component mixtures in this work. In addition, the rheological model for binary mixtures is also extended to multi-component mixtures. In contrast to the percolation velocity-based empirical segregation models that do not account for the rheology and need prior knowledge of the velocity field, the present approach accounts for the inter-coupling of rheology with segregation. The momentum balance equations are solved, along with the mixture rheological model as well as the multi-component density segregation model, to obtain concentration fields using an iterative numerical method. The theoretical predictions are compared with discrete element method (DEM) simulations for ternary, quaternary and quinary granular mixtures differing in density. The steady-state profiles for the concentration of different species as well as other flow properties predicted from the theory are in excellent agreement with the DEM simulation results for a variety of compositions over a range of inclination angles for different density ratios. Through this work, we take the first essential step towards proposing a generalised particle force-based segregation theory for multi-component mixtures differing in size and/or density.

Solvent Effects Used for Optimal Simultaneous Analysis of Amino Acids via 19F NMR Spectroscopy.

19F NMR has been extensively used in simultaneous analysis of multicomponent due to its 100% natural isotope abundance, high NMR-sensitivity, and wide-range chemical shifts. The solvent effects are usually observed in NMR spectroscopy and cause large changes in 19F chemical shifts. Herein, we propose that the simultaneous analysis of a complex mixture can be achieved using solvent effects via 19F NMR spectroscopy, such as a mixture solution of amino acids (AAs). AAs are not only cell-signaling molecules, but are also considered as biomarkers of some diseases. Hence, the analysis of AAs is important for human health and the diagnosis of diseases. In this work, the key to the success of sensing 19 biogenic AAs is the use of 2-fluorobenzaldehyde (2FBA) as a highly sensitive derivatizing agent and solvent effects to produce distinguishable 19F NMR signals. As a result, the resolution of 19F NMR spectroscopy of multiple 2FBA-labeled AAs is obviously higher than other methods based on 19F NMR. Moreover, 14 and 18 AAs can be satisfactorily differentiated and unambiguously identified in different complicated media supporting the growth of mammalian cells. Furthermore, quantification of the concentration of AAs can be made, and the limit of detection reaches 10 μM. Our work provides new insights into the simultaneous analysis of a multicomponent mixture based on solvent effects by 19F NMR spectroscopy.

Benchmark single-step ethylene purification from ternary mixtures by a customized fluorinated anion-embedded MOF

Ethylene (C2H4) purification from multi-component mixtures by physical adsorption is a great challenge in the chemical industry. Herein, we report a GeF62- anion embedded MOF (ZNU-6) with customized pore structure and pore chemistry for benchmark one-step C2H4 recovery from C2H2 and CO2. ZNU-6 exhibits significantly high C2H2 (1.53 mmol/g) and CO2 (1.46 mmol/g) capacity at 0.01 bar. Record high C2H4 productivity is achieved from C2H2/CO2/C2H4 mixtures in a single adsorption process under various conditions. The separation performance is retained over multiple cycles and under humid conditions. The potential gas binding sites are investigated by density functional theory (DFT) calculations, which suggest that C2H2 and CO2 are preferably adsorbed in the interlaced narrow channel with high aff0inity. In-situ single crystal structures with the dose of C2H2, CO2 or C2H4 further reveal the realistic host-guest interactions. Notably, rare C2H2 clusters are formed in the narrow channel while two distinct CO2 adsorption locations are observed in the narrow channel and the large cavity with a ratio of 1:2, which accurately account for the distinct adsorption heat curves.

Investigating the ecotoxicity of construction product eluates as multicomponent mixtures

BackgroundThe release of hazardous compounds from construction products can harm human health and the environment. To improve the sustainability of construction materials, the leaching of substances from construction products and their potential environmental impact should be assessed. Twenty-seven construction products from different product groups were examined with a combination of standardized leaching tests (dynamic surface leaching test and percolation test) and biotests (algae, daphnia, fish egg, luminescent bacteria, umu and Ames fluctuation tests). To identify the released substances, extensive qualitative and quantitative chemical analyses were performed, including gas chromatographic and liquid chromatographic screening techniques.ResultsMany of the tested eluates caused significant ecotoxic effects. Particularly high ecotoxicities were observed for grouts (lowest ineffective dilution (LID) up to 16384) and cork granules (LID up to 24578). The results of ecotoxicity tests allow the prioritization of the eluates that should be subjected to detailed chemical analyses. Organic screening by different methods and ranking the identified substances based on recorded hazard classification is a suitable approach to identify the relevant toxic substances.ConclusionsDetermining the ecotoxicity of eluates from construction products records the summary effect of all leachable substances. This instrument is especially useful for construction products of complex and largely unknown composition. The ecotoxicological and the chemical–analytical approach complement each other in an ideal way to characterize the potential hazard of eluates from construction products and to identify the environmentally hazardous components in these eluates. Our results confirm that the proposed harmonized methods for testing eluate toxicity are an adequate and applicable procedure to move toward a more sustainable way of building and to reduce toxic effects of construction products in their use phase in the environment..

Chromatography in Catalysis

The main applications of gas chromatography for investigation of catalysts and catalytic processes are considered. The development of the sampling method as well as the microcatalytic and pulsed methods is described in historical aspect. The paper presents the advanced and promising directions of gas chromatographic studies, and the instruments providing efficient separation of multicomponent mixtures of substances with the control of complex catalytic reactions.

Environmental characteristics of thermal utilization of waste with external and internal supply of thermal energy

THE PURPOSE. Identification of optimal regimes for autothermal and allothermic methods of gasification of plant biomass in terms of energy parameters of generator gases, as well as determination of environmental indicators during subsequent combustion of generator gases to obtain thermal energy.METHODS. When modeling gasification processes, a nonstoichiometric model was used, based on the assumption that a chemically reacting multicomponent mixture is in a state of thermodynamic and chemical equilibrium, which corresponds to the minimum value of the isobaric-isothermal potential. When modeling the combustion of generator gas in a mixture with air, a kinetic model of a perfectly mixed flow reactor was used and the detailed mechanism of chemical interaction for the C-H-O-N-S reacting system was taken into account. The calorific value of generator gas obtained by steam gasification and external supply of thermal energy is significantly higher than the calorific value of gas obtained by internal supply of thermal energy. However, the values of the energy potential and thermochemical efficiency are very close for both types of gasification.RESULTS. For plant biomass with a given averaged elemental composition, gasification conditions are determined that increase the degree of conversion of initial materials into generator gas. In particular, for the autothermal gasification method, the maximum calculated values of the energy potential of dry ash-free generator gas and thermochemical efficiency were obtained at an excess air coefficient α ≈ 0.32. For the allothermic gasification method, the maximum calculated values of the energy potential of the generator gas and the thermochemical efficiency correspond to the gasification temperature range T ≈ 1050 -1100 K and the mass fraction of the supplied steam gH2O ≈ 0.217. To ensure these conditions, it will be necessary to supply thermal energy through combustion of ≈ 37 wt. % generator gas. Generator gas produced by the allothermic method has higher energy performance, and the negative impact on the environment during its subsequent combustion is characterized by lower specific CO and CO2 emissions in terms of a ton of reference fuel.

Extraordinary Separation of Acetylene-Containing Mixtures in a Honeycomb Calcium-Based MOF with Multiple Active Sites.

Acetylene (C2H2) separation from multicomponent mixtures is vitally important but industrially challenging for the collection of high-purity C2H2. To address this requirement, the reaction between the alkaline-earth Ca2+ ions with a dicarboxylate-diazolate linker, 4,6-di(1H-tetrazol-5-yl)isophthalic acid (H4dtzip), gave rise to a new metal-organic framework (MOF) material [Ca(dtzip)0.5H2O]·2H2O (1). The material presents unique regular tubular channels based on threefolded helical rod-like secondary building units with rich open metal sites and exposed organic hydrogen-bonding N/O acceptors that enhance the interactions with C2H2 molecules, endowing significant selectivity for C2H2 over C2H4 (5.4), C2H6 (5.6), CH4 (30.0), and CO2 (7.7) at 298 K and 100 kPa. Column breakthrough experiments confirmed the extraordinary C2H2 separation performance of the material with the separation time intervals in the range of 18-24 min g-1 for binary (C2H2-C2H4, C2H2-C2H6, C2H2-CO2, and C2H2-CH4) or ternary (C2H2-C2H4-C2H6 and C2H2-C2H4-CO2) gas mixtures under dynamic conditions.

Miscibility in systems containing (poly(oxymethylene) ethers (OME) + hydrocarbons + water)

Poly(oxymethylene) dimethyl ethers (OME) are interesting synthetic fuels: they have better combustion properties than fossil diesel fuel and can be obtained from renewable resources. Furthermore, they can be blended with hydrogenated vegetable oils (HVO) to obtain a new class of environmentally benign fuels. However, it has been observed in technical processes that initially homogeneous mixtures of (OME + HVO) split into two liquid phases after some time, which is unacceptable for use as fuels. It is assumed that this de-mixing is a consequence of the uptake of small amounts of water from the air by the mixtures. However, up to now, only qualitative information on this phenomenon was available. We have, therefore, carried out systematic experimental studies of liquid–liquid equilibria (LLE) and liquid–liquid–liquid equilibria (LLLE) in ternary model systems of the type (OME + n-alkane + water) at temperatures between 265 and 293 K. The n-alkanes were (n-dodecane, n-hexadecane); two different OME were studied, OME2 and OME4, respectively. Additionally, also multicomponent mixtures containing different OME and mixtures containing additionally the aromatic hydrocarbon toluene were studied. The results were modeled using UNIFAC, a group-contribution model of the Gibbs excess energy, and a good correlation of the observed complex phase behavior was obtained. The results from the present work confirm that the uptake of small amounts of water is the reason for the phase split observed in technical (OME + HVO) mixtures. Measures to circumvent this problem are discussed.

Development of a reduced kinetic chemical mechanism of gasoline surrogate containing alcohols and pentenes

Based on the methods of DRGEP, FSSA, reaction path analysis, and sensitivity analysis, the detailed mechanisms of 1-pentene, 2-pentene, and 2-methyl-2-butene are comprehensively reduced and combined with the mechanisms of TRF, methanol, ethanol, and n-butanol. A reduced mechanism of multi-component is proposed to predict gasoline combustion in the engine. It is rare in previous study about mechanisms of surrogate fuels that used pentene to represent unsaturated hydrocarbons, which is the most abundant olefin in actual gasoline in China. JSR experiments were carried out on the mixed fuels of isooctane/methanol/n-butanol and isooctane/1-pentene with different equivalence ratios under the condition of 1.03 atm and temperature range from 500 K∼1000 K, and the component concentration curves were obtained. The accuracy of the multi-component reduced mechanism is verified by JSR experimental data. The results showed that this mechanism could well fit the concentration curve of reactants and final reaction products, and showed the same change trend for intermediate products. The accuracy of the pentene mechanism is verified by the experimental data of ignition delay time and laminar flame velocity. The prediction of the ignition delay time of pentenes is accurate in the middle and high temperature regions, and the prediction in the low temperature region is slightly lower than that of the detailed mechanism, but it can predict the trend of ignition delay time and reflect the low temperature reaction properties of them. The simulated values of 1-pentene can well fit the experimental data of laminar flame velocity under various working conditions, and the difference in laminar flame velocity of three isomerides is also well reflected in this mechanism. The ignition delay time of multi-component mixtures was verified under different pressures by using the mixed fuels of G-A, G-B, and G-C. The results show that this mechanism can predict the ignition delay time of G-A and G-B more accurately under pressure of 20 atm, but the predicted values are lower under 50 atm pressure. Under the pressure of 10 atm, 30 atm, and 50 atm, the ignition delay time of this mechanism can well fit the experimental data of G-C fuel, while the predicted value at low temperature is slightly higher.

ДОСЛІДЖЕННЯ ВЛАСТИВОСТЕЙ БАГАТОКОМПОНЕНТНИХ СУМІШЕЙ БОРОШНА

Flour is a component of many types of food products, such as bakery, pasta, confectionery, meat, fish emulsion products, sauces and low-calorie mayonnaise. The expansion of the range of flour products is accompanied by the introduction of flour blends into the recipe and their enrichment with useful nutrients. The article presents the results of research into the properties of various types of flour and their multicomponent mixtures. The indicator of moisture retention capacity was determined experimentally by the centrifugation method and calculated by the principle of additivity. It is possible to adjust this indicator by changing the number of individual components in mixtures containing different types of flour.The use of blends of flour in the recipes of food products ensures the expansion of their assortment and enrichment with useful nutrients. Bread, pasta, confectionery, meat and fish emulsion products, sauces and low-calorie mayonnaises containing flour are complex systems. Important and relevant for such systems is the study of the properties of the constituent components and the study of their influence on the quality of finished products.Inthe process of developing recipes for flour products and products that include different types of flour, it is necessary to take into account the indicators of both individual types of flour and their mixtures with different amounts of components inthe system. It is also important to study the possibility of adjusting the properties of flour compositions by changing the numberof individual components in their composition.Analysis of research and publications showed that considerable attention is paid tothe use of non-traditional flour raw materials in the production of food products. The conducted research mainly concerns the study of the properties of individual types of flour, which makes the urgent task of researching multicomponent mixtures of flour.The purpose of the article is to study the properties of both individual types of flour and their multicomponent mixtures, establish the possibility of regulating such an indicator as moisture-retaining capacity for blends, as well as the formation of multicomponent flour mixtures with specified parameters.In the work, indicators of the moisture-retaining capacity of various types of flour and their multicomponent mixtures are determined. Calculations of the moisture-retaining capacity of two-, three-, and four-component blends of flour were carried out according to the principle of additivity, taking into account the share of each component in the mixture. The results were obtained regarding the possibility of increasing the water-absorbing capacity of wheat flour by adding bran to it. The presented materials can be used to form blends of flour with the specified indicators of moisture retention capacity

A cage-specific hydrate equilibrium model for robust predictions of industrially-relevant mixtures.

Understanding the thermophysical properties and phase behaviour of gas hydrates is essential for industrial applications ranging from energy transport and storage, CO2 capture and sequestration, to gas production from hydrates found on the seabed. Current tools for predicting hydrate equilibrium boundaries typically use van der Waals-Platteeuw-type models which are over-parameterised containing terms with limited physical basis. Here we present a new model for hydrate equilibrium calculations with 40% fewer parameters than existing tools but with equivalent accuracy, including for multicomponent gas mixtures and/or systems with thermodynamic inhibitors. By eliminating multi-layered shells from the model's conceptual basis and focusing on Kihara potential parameters for guest-water interactions specific to each hydrate cavity type, this new model provides insight into the physical chemistry governing hydrate thermodynamics. The model retains the improved description of the empty lattice developed recently by Hielscher et al. but couples the hydrate model with a Cubic-Plus-Association Equation of State (CPA-EOS) to describe fluid mixtures with many more components including inhibitors such as methanol and mono-ethylene glycol used by industry. An extensive database of over 4000 data points was used to train and evaluate the new model and compare its performance against existing tools. The absolute average deviation in temperature (AADT) achieved with the new model is 0.92 K for multicomponent gas mixtures, compared with 1.00 K for the widely-known model of Ballard and Sloan, and 0.86 K for the CPA-hydrates model implemented in the MultiFlash 7.0 software package. With fewer, more physically justified parameters, this new cage-specific model provides a robust basis for improved hydrate equilibrium predictions particularly for industrially-important, multi-component mixtures containing thermodynamic inhibitors.