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In this work, we propose an alternative method for the utilization of sleepers, based on the use of a supercritical fluid extraction process. The preference for the implementation of a supercritical fluid extraction process for “extractable-extractant” systems exhibiting I–II types of phase behavior is given. On the example of supercritical fluid extraction of the impregnation material of spent wood railway sleepers, the efficiency of replacing the carbon dioxide participating as an extractant with a propane/butane mixture, which provide the desired change in the type of phase behavior in relation to such components of the impregnation material as phenol, anthracene and naphthalene is shown. The phase equilibria of thermodynamic systems involving carbon dioxide and a propane/butane mixture on the one hand and coal oil components such as phenol, anthracene, and naphthalene on the other are studied. The proposed method of processing spent railway sleepers allows you to select from it up to 97 % of the mass impregnation source material.

Using modified amino ethers of boric acid, porous polyurethanes are synthesized, the porous morphology of which is due to the peculiarities of the hyperbranched macromolecular architecture of amino ethers of boric acid. A change in the structure of amino ethers of boric acid by the introduction of terminal bulky substituents with hydroxyl groups contributes to a change in the size and pore size distribution of polyurethanes based on amino ethers of boric acid. It is shown that one of the reasons for the heat-sensitive vapor permeability of porous polyurethanes is the hydrophilic nature of the pore surface. Film samples of porous polyurethanes have proven to be an effective substrate for the targeted cultivation of connective tissue at the cellular level.

The results of generalizing the solubility of aromatic hydrocarbons in supercritical carbon dioxide using the entropy method of similarity theory are presented. Experimental data from different authors on the solubility of 11 substances studied in a temperature range from 300 to 350 K (728 experimental points and 50 isotherms) are subjected to generalization. It is shown that the dependency makes it possible to compute the solubility of aromatic hydrocarbons subjected to generalization in supercritical carbon dioxide to an acceptable accuracy.

The paper deals with the problem of material dispersion using supercritical fluid media. At the same time, emphasis is made on modifications (SAS, GAS, SEDS and ASES) of the supercritical fluid anti-solvent method of dispersion. The results of SAS method implementation for dispersion of pure polycarbonate and polycarbonate doped with “CdSe/CdS - core/shell” quantum dots (carried out in the pressure range of 8.0-25.0 MPa at temperatures of 313.15 K and 358.15 K) are submitted. The range of the operating parameters has been established through the example of pure polycarbonate dispersion, which provides the production of nanoparticles with the size range of 10 100 nm. Encapsulation of CdSe/CdS quantum dots into polycarbonate using the SAS method has no effect on optical properties of the encapsulated quantum dots. The results of paracetamol dispersion using the SEDS method are presented. The effect of operating conditions of the paracetamol dispersion process on morphology of the obtained product is described. Co-dispersion of ethylene–vinyl acetate copolymers and low-density polyethylene mixtures by SEDS method has been carried out under pressures of 8.0-25.0 MPa at temperatures of 313 K, 323 K, and 333 K. The comparison of melting and crystallization between the resulting copolymer mixtures and mixtures with the same composition obtained by mixing in the liquid melt, has shown that implementation of SEDS results in an increase of crystallinity degree of the polymer mixtures.

The thermal conductivity of two pyrrolidinium-based ionic liquids (ILs) 1-propyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (short name is [C3C1pyr][NTf2]) and 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide (short name is [C4C1pyr][NTf2]) have been measured over the temperature range from (279–438) K at atmospheric pressure. Measurements were made using the steady-state hot-wire technique. The combined expanded uncertainty of the temperature and thermal conductivity measurements at the 95% confidence level with a coverage factor of k = 2 is estimated to be 0.02 K and 3.2%, respectively.The measured thermal conductivities ( λ ) together with our previously reported heat capacity ( C P ) and density ( ρ ) data were used to calculate thermal diffusivity ( a ) of the ILs using well-known thermodynamic relation a = λ / ρ C P .The new measured values of the thermal conductivity have been also used to check the reliability and accuracy of the various predictive methods (generalized model, group contribution method).

Amphiphilic poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate cross-linked block copolymers based on triblock copolymers of propylene and ethylene oxides with terminal potassium-alcoholate groups (PPEG), octamethylcyclotetrasiloxane (D4) and 2,4-toluene diisocyanate (TDI) were synthesized and investigated. In the first stage of the polymerization process, a multiblock copolymer (MBC) was previously synthesized by polyaddition of D4 to PPEG. The usage of the amphiphilic branched silica derivatives associated with oligomeric medium (ASiP) leads to the structuring of block copolymers via the transetherification reaction of the terminal silanol groups of MBC with ASiP. The molar ratio of PPEG, D4, and TDI, where the polymer chains are packed in the &ldquo, core-shell&rdquo, supramolecular structure with microphase separation of the polyoxyethylene, polyoxypropylene and polydimethylsiloxane segments as the shell, was established. Polyisocyanurates build the &ldquo, core&rdquo, of the described macromolecular structure. The obtained polymers were studied as membrane materials for the separation of gas mixtures CO2/CH4 and CO2/N2. It was found that obtained polymers are promising as highly selective and productive membrane materials for the separation of gas mixtures containing CO2, CH4 and N2.

The synthesis of palladium and palladium–silver catalysts using supercritical fluid CO2-impregnation (static conditions) was studied. It was shown that the highest amount of metal is impregnated onto a support in a temperature range of 318–323 K and a pressure range of 19.0–23.0 MPa. The activities of palladium catalysts prepared according to the proposed procedure were comparable with those of currently produced industrial samples.

Current paper represents the results of the study on extraction of hydrocarbons from oil emulsions using liquid and supercritical extraction processes. High-viscosity oil from Ashalchinskoy...

Absolute measurements of the thermal conductivity of n-hexane performed in a coaxial cylinder cell operating under steady state conditions are reported. The measurements of the thermal conductivity of n-hexane were carried out in the liquid along nine quasi-isotherms below the critical temperature (Tc = 507.82 K), in the low-pressurized gas at some temperatures below the critical temperature, and in the compressed gas along nine quasi-isotherms above the critical temperature. Additional thermal conductivity measurements were also performed in the liquid and the gas along the isobar at 0.101325 MPa and in the vapor close to the saturation curve for temperatures below the boiling temperature (Tb = 341.865 K). The present 577 data cover roughly the temperature range from 293 K to 612 K and the pressure range from 0.01 to 40 MPa. An analysis of the different sources of error leads to an estimated uncertainty of approximately 1.5%. The experimental results are correlated separating the additional contributions of the temperature effect and the density effect (in the density range from 0 to 670 kg m−3). A brief comparison is shown with previous experimental measurements of the thermal conductivity of n-hexane.

A mathematical model that describes the kinetics of the extractional regeneration of a heterogeneous catalyst by a solvent, including that in its supercritical state, has been proposed. A comparison of the results of numerical and real experiments reveals their qualitative compliance over the entire time range of the process, as well as the quantitative agreement between them within the time range that corresponds to the high saturation of the catalyst with deactivating compounds.

The effect of the reaction medium and synthesis temperature on the polyaddition of 2,4-toluene diisocyanate to a macroinitiator representing a potassium-substituted block copolymer of propylene and ethylene oxides is revealed. Factors affecting the polyaddition accompanied by the opening of isocyanate groups via the carbonyl component are the use of catalytic amounts of acidic compounds, water in combination with trimethylamine, and maintenance of fairly low temperatures. The dielectric properties and static electrical conductivity of polymers obtained under different reaction conditions are studied. It is shown that the preferential formation of polyisocyanates of the acetal nature and, thus, block copolymers with their participation can be responsible for change in the electrophysical properties of the polymers.

The VLE properties and the critical parameters of ternary mixture of CO2 + toluene/dichloromethane involved in the SEDS precipitation process were studied. The derived VLE and the critical properties data were used to select most preferred thermodynamic conditions (optimal SEDS process parameters) for implementation of the process of supercritical dispersion of the polymer mixtures of EVCA-113/PC using Solution Enhanced Dispersion by Supercritical (SEDS) fluids method. SEDS process has been used to produce ethylene vinyl acetate copolymer (EVCA)/polycarbonate (PC) polymer mixture microparticles at operating parameters from (8 to 25) MPa in the temperature range from (313 to 323) K and at concentration of (0, 0.25, 0.50, 0.75, and 1.00) mass fraction of PC. The effect of SEDS process operating variables (temperature, pressure, and concentration) on EVCA/PC polymer mixtures microparticle sizes and their physical–mechanical properties was studied. We showed that it is possible to modify particle dimensions and physical - mechanical properties of SEDS produced EVCA/PC polymer mixtures by changing the operating parameters. SEM and DSC were used to characterize of the produced polymer mixture microparticles. The crystallization kinetics (degree of crystallinity) and phase -transformation characteristics (heat of fusion and melting temperature) of polymer mixtures obtained by melt mixing and using the SEDS method were studied. The mechanical characteristics such as tensile strength and elongation-at-break were studied as a function of process conditions (temperature, pressure, and concentration).

Experimental results on the solubility of ammonium palmitate as a potential fabric water-repellent agent in supercritical carbon dioxide (SC-CO2)—pure and modified with acetone and dimethyl sulfoxide—are presented. The measurements are performed at temperatures 318.2 and 328.2 K in the pressure range from 10.0 to 32.5 MPa in a dynamic regime. The experimental solubility data are described using the Peng–Robinson equation of state. The results of treatment of various types of cotton fabrics by ammonium palmitate in SC-CO2 are presented. The contact (wetting) angle of the treated samples is determined and the increase in their hydrophobicity is demonstrated.

The process of wood drying is studied in supercritical (SC) CO2 and SC-CO2 containing 5 vol % ethanol at temperatures of 323, 343, and 353 K and pressures of 10, 20, and 30 MPa. It is established that 40–87% of moisture is removed from wood in the first cycle of drying. An increase in the duration of the decompression stage of the drying process decreases the number of cracks in the wood samples. The solubility of propiconazole is studied in SC-CO2 at 323, 343, and 353 K in the pressure range of 10–30 MPa using a dynamic method. Rather high saturation concentrations of (3–5) × 10–3 mol/mol CO2 are obtained, which indicates the potential benefits of using SC-CO2 as a solvent in wood impregnation with propiconazole. Continuous impregnation is achieved when impregnating wood with propiconazole from SC-CO2. The impregnation efficiency increases with increasing pressure and duration of the process.

The extraction process with propane: butane = 3: 1 (by mass) mixture in the liquid and supercritical fluid states was used to extract petroleum products containing 12.05 mass % of anhydrous oil sludge as solid particulates. The extraction was carried out at 85–160°С and 5–50 MPa. The desired oil product contains 2.8 mass % of sulfur, it has a density of 880 kg/m3 and a kinematic viscosity of 73.75 mm2/s at 20°С as well as start and end boiling point values of 43.6 and 325°С, respectively.

Experimental results are reported on the solubility of ammonium palmitate, which is one of potential fabric water-repellent agent, in pure supercritical carbon dioxide (SC-CO 2 ) and (SC-CO 2 ) modified by acetone and dimethyl sulfoxide. The measurements were performed at temperatures from 308.15 K to 333.15 K, in the pressure range from 10.0 to 32.5 MPa, on an experimental installation using a dynamic search method. Experimental solubility data are described using the Peng-Robinson equation. The results of the treatment of various types of cotton fabrics by ammonium palmitate in supercritical CO 2 environment are presented. The main goal of the treatment was to make cotton fabrics water repellent. The water contact angle (WCA), of the hydrothermally treated samples was determined and the increase in their hydrophobicity was found to be in the ultrahydrophobic (WCA > 120°) and superhydrophobic (WCA > 150°) categories.

The results of using the processes of liquid and supercritical fluid extraction to separate petroleum products from oil sludge have been presented. A mixture that consists of 75 wt % propane and 25 wt % butane has been used as an extractant. The initial oil sludge is characterized by the absence of water and a content of mechanical impurities in the amount of 12.05 wt %. Extraction processes are carried out in the temperature range of 85–160°C and pressure interval of 5–50 MPa. The results of modeling the extraction process for the separation of petroleum products from oil sludge have been presented.

The results of using processes of liquid and supercritical fluid extraction to isolate hydrocarbons from oil-bearing sands have been presented. The initial oil-bearing sand is characterized by a concentration of hydrocarbons of 7.23 wt % of the total weight of the sandstone. A mixture containing 75 wt % propane and 25 wt % butane has been used as the extracting agent. Extraction processes have been carried out in a temperature range of 80–140°C and pressure range of 5–10 MPa.

The reaction of transesterification of rapeseed oil in ethanol under supercritical fluid conditions in the 320-380 ϵC temperature range, under 30 MPa pressure, for ethyl alcohol to rapeseed oil molar ratios of (6-20):1 was studied experimentally. Dependencies of kinematic viscosity of the reaction product on the temperature, molar ratio of the starting reagents, and duration of reaction implementation were obtained. A correlative dependence that allows calculation of the content of ethyl esters of fatty acids in the transesterification product is proposed using experimental data on the kinematic viscosity values of the reaction product.

The authors present the results of investigation and experimental implementation of several processes: production of heavy oil residue and its deasphaltizing and impregnation of carbonate rock with deasphalted oil. Heavy oil residue has been produced during fractionation of highly-vicious oil by steam-thermal method. Deasphaltizing of oil-residue and impregnation of carbonate rock are implemented with the use of extraction and supercritical fluid impregnation processes with propane-butane solvent.

A quantum-chemical study of the mechanism of transesterification reaction carried out in the traditional and supercritical fluid (SCF) conditions has been performed. Samples of biodiesel fuel have been derived from rapeseed oil in the environment of supercritical ethanol using a flow type unit, both in the absence and in the presence of heterogeneous catalysts-metal oxides. Experimental studies of kinematic viscosity of a large array of samples of derived biodiesel have been performed. The viscous correlation allowing determining the content of the desired product-fatty acid ethyl esters (FAEE)-in biodiesel samples, has been made based on the obtained experimental data on the kinematic viscosity of biodiesel samples. The influence of change of the dielectric permittivity of working environments on the rate of reaction of transesterification in the supercritical fluid conditions has been revealed.

Polyurethanes composed of aromatic components are synthesized using the catalytic effect of potassium alcoholates on the reaction of urethane formation occurring with participation of 4,4'-dihydroxy-2,2-diphenylpropane, 4,4'-diphenylmethane diisocyanate, and polyisocyanate, which is a mixture of 4,4'-diphenylmethane diisocyanate and its branched derivatives. In the case of 4,4'-diphenylmethane diisocyanate, segmented polyurethanes with the predetermined length of the rigid block are formed, while the use of polyisocyanate gives rise to framed aromatic polyurethanes. The use of macroinitiators as carriers of potassium alcoholate groups does not cause microphase separation of flexible and rigid segments.

The hyperbranched polymers have drawn intensive attention in the design of macromolecules and functional materials because of their unique physical and chemical properties resulting from the branched architecture and the high number of functional groups. In the present study, by means of light scattering, viscosimetry, thermomechanical analysis, tensile stress–strain, mechanical loss tangent and water vapor permeability measurements, we demonstrate the hierarchical macromolecular organization of organoboron polyurethanes synthesized using sterically hindered amino ethers (AEBA) of boric acid. It is shown that the water vapor permeability of polyurethanes obtained on the basis of sterically hindered aminoethers of boric acid is due to the peculiarities of the chemical structure of AEBA, which can exhibit an ionomeric nature and the presence of steric hindrances created in the hyperbranched structure of AEBA, which can lead to an increase in free volume in such polyurethanes.

Amphiphilic branched silica derivatives associated with oligomeric medium (ASiP) were obtained using tetraethoxysilane, polyoxyethylene glycol and low molecular weight polydimethylsiloxane. The creation of a silica core was based on tetraethoxysilane hydrolysis and condensation reactions by using water and a potassium diethylene glycolate as the catalyst. These reactions proceeded with the sequential participation of polyoxyethylene glycol and polydimethylsiloxane in parallel transetherification reactions. Microporous polymer film based on 2,4-toluene diisocyanate and block copolymers of propylene and ethylene oxides with terminal potassium-alcoholate groups were modified by ASiP. It has been shown that ASiP at the phase interface between thermodynamically incompatible macrochains performs the function of a link. It leads to a significant increase of intermolecular interactions and the supramolecular organization of the modified microporous polymers.

International audience; Measurements of the thermal conductivity of supercritical n-hexane performed in a coaxial cylinder cell operating in steady state conditions are reported. The present 1321 data of the thermal conductivity of n-hexane were carried out along ten quasi-isotherms above the critical temperature. These data cover the temperature range from 508.17 K to 553.00 K and the pressure range 0.l to 10 MPa. An analysis of the various sources of error leads to an estimated uncertainty that do not exceed 4% (95 level of confidence). The parameters of a background equation previously determined from 577 data of the thermal conductivity of gas and liquid n-hexane are reused here in order to analyze the critical enhancement of the thermal conductivity as a function of temperature and density. A set of theoretical Ising-like equations are re-formulated to describe the thermal conductivity critical enhancement along the near-critical isochoric lines in terms of the effective power laws fitting the singular behavior of the needed fluid properties as functions of the finite temperature distance to the critical point. Assuming the knowledge of the regular temperature behavior of the viscosity, the critical enhancement of the thermal conductivity appears then only characterized by a single effective amplitude. Such a separated analysis of the well-defined temperature effects provides the empirical functional form of the density effects, as a 6th-order polynomial density function, which can be normed whatever the temperature. Finally, our complete formulation of the total thermal conductivity describes, within three standard deviations (with SD = 1.0388%), the 1898 thermal conductivity measurements of n-hexane from 293 to 612 K and densities up to 670 kg m−3.

Organophosphorus polyurethane ionomers (AEPA-PU) based on aminoethers of ortho-phosphoric acid (AEPA) were obtained and studied as pervaporation membrane materials for separating isopropanol/water mixtures. The regularities of the change in the water vapor permeability of AEPA-PU were also investigated. It has been established that an increase of solute content in the composition of the urethane-forming system and the content of ionogenic groups in AEPA leads to a noticeable increase in the vapor permeability of the resulting film materials. An increase in water vapor permeability values is accompanied by a significant increase in the pervaporation characteristics of AEPU-PU. It was shown that the conditions promoting clustering of phosphate anions cause an increase in the values of the vapor permeability coefficient of AEPA-PU obtained using polyoxypropylene glycol. However, the hydrophobicity of the polypropylene glycol surrounding the clusters makes it difficult for water to move through the polymer matrix. Due to the hydrophilicity of polyoxyethylene glycol, the highest values of water vapor permeability and pervaporation characteristics are achieved for AEPA-PU synthesized using PEG.

Isobaric heat capacity, C P , of binary aqueous 1,2 − propanediol solutions have been measured over the temperature range from room temperature 298.15 K to 473.15 K at pressures up to 30 MPa using differential scanning calorimeter (DSC, ITS-400). The measurements were performed for three concentrations of 0.0731, 0.1914, and 0.4153 mol fraction of 1,2 − propanediol. The expanded uncertainty of the heat capacity ( C P ), pressure (P), temperature (T), and concentration (x) measurements at the 95% confidence level with a coverage factor of k = 2 is estimated to be 2.4%, 0.05%, 15 mK, and 0.0001, respectively. The measured C P P T x data have been used to calculate excess molar heat capacities ( C Pm E ) of the mixture. The second temperature derivatives of specific volume or curvature of the Vm-T isobars have been calculated using the pressure dependence measured heat capacities along the isotherms as ∂ 2 V m / ∂ T 2 Px = - T - 1 ∂ C Pm / ∂ P Tx . Some unusual behaviour of C P in the low concentration range (below 0.2 mol fraction, dilute mixture) along the each measured isotherms-isobars was found.

In the context of the development of the catalyst regeneration procedure via supercritical fluid CO2 extraction, some thermodynamic properties of the anthracene–carbon dioxide mixture in supercritical fluid state have been studied. Data on anthracene solubility in pure and modified (dimethyl sulfoxide, 5 wt %) supercritical carbon dioxide (SC–CO2), the heat capacity of anthracene and its mixtures with carbon dioxide, and the heat of solution of anthracene in SC–CO2 are presented. Anthracene solubility in SC–CO2 is described satisfactorily using the Peng–Robinson equation of state.

The solubility of ammonium palmitate in supercritical carbon dioxide is studied in the dynamic regime at 308.15–333.15 K and 10.0–35.0 MPa. Experimental data are described in the framework of the Peng–Robinson equation of state.

Noncatalytic and catalytic transesterification of rape oil were studied in an ethanol medium under supercritical fluid conditions, ultrasonic effect, temperature range from 623 to 653 K, 30 MPa, and with 12: 1 and 18: 1 alcohol to oil mole ratios. An effect of heterogeneous catalysts on the reaction rate was defined. Correlation dependence between the amount of fatty acid ethyl esters in biodiesel fuel and kinematical viscosity of the reaction product was determined.

In Europe, rapeseed is a renewable raw material which has been widely used for the production of biodiesel by various processes. The transesterification reaction of rapeseed oil with ethanol to biodiesel in supercritical fluid conditions was investigated using several heterogeneous catalysts and preliminary ultrasonic emulsification of the reaction mixture, to run the reaction at mild conditions. Phase equilibrium of fatty acids in supercritical ethanol was study to determine the operating condition in supercritical states. Transesterification experiments were carried out under a pressure of 30 MPa, with ethanol to oil molar ratio (in the range of 12:1⿿20:1), temperature (623 K to 653 K), and the catalyst loading level and type were the main parameters. The most important characteristics of Al 2 O 3 support catalyst and the impregnation method with aqueous solution of metal nitrates are also described. Yields of Fatty Acids Ethyl Ester (FAEE) are reported for different ZnO/Al 2 O 3 , MgO/Al 2 O 3 , SrO/Al 2 O 3 catalysts in different experimental conditions. The higher yield of 97.46% was obtained under the optimal conditions 623 K, 30 MPa, 12:1 ethanol/FAEE molar ratio, with SrO/Al 2 O 3 (2 wt.% SrO) impregnated catalyst.

A comprehensive process for the deasphaltizing of heavy oil residue and subsequent treatment (impregnation using a solvent in the supercritical fluid state) of a carbonate macadam by bituminous compounds (deasphaltizate) is developed. The purpose is to improve the functionality of the material and, above all, to reduce its water absorption capacity. The process parameters are specified based on the newly obtained data on the thermal capacity of heavy oil residue and deasphaltizate. The results of the process of experimental implementation and the characteristics of impregnated macadam, including the water absorption capacity which decreased from 3.6 to 0.54%, are presented.

The authors present the results of implementation of liquid and supercritical fluid extraction processes with the purpose of extracting oil products from oil sludge. A mixture consisting of propane (75 wt%) and butane (25 wt%) has been applied as the extractant. Initial oil sludge has been characterized by the absence of water and the content of solids in amount of 12.05% by weight. The extraction processes have been carried out in the temperature range of 85–160°C and pressure range of 5–50 MPa.

Solubility of naphthalene in supercritical solvent mixture (0.527 propane + 0.473 n-butane mole fraction) was measured at three constant temperatures of 403 K, 423 K, and 443 K over the pressure range from (1.08 to 6.21) MPa. The measurements were made using high-temperature and high-pressure optical cell. The combined expanded uncertainty of the temperature, pressure, and concentration measurements at 95% confidence level with a coverage factor of k = 2 is estimated to be 0.15 K, 0.05%, and 3%, respectively. For validation of the performance and reliability of the new high-pressure VLE apparatus the critical point parameters of pure component of (propane) and binary mixture (0.609 propane + 0.391 n-butane mole fraction) for which reliable literature data are available have been made. The measured values of VLE properties for ternary mixture of naphthalene + SC (propane/n-butane) were compared with the values predicted from GERG model for natural gas main constituents and other natural gas component containing mixtures.

International audience; Measurements of the thermal conductivity of ethene performed for the first time, in a coaxial cylinder cell, operating in steady state conditions are reported. The measurements of the thermal conductivity of ethene were carried out along eight quasi-isotherms above the critical temperature. The present data cover the temperature range from 283.46 K to 425.00 K, and the pressure range 0.1–100 MPa. An analysis of the different sources of error leads to an estimated uncertainty (0.95 level of confidence) of ±3%. The parameters of a background equation were determined from experimental data in order to analyze the critical enhancement of the thermal conductivity as a function of temperature and density. Based on the measurement of more than 500 experimental points, a phenomenological equation is provided to describe the thermal conductivity of ethene, from 270 K to 425 K and densities up to 500 kg m−3.

Using high-speed camera, the experiments were performed to research evaporation of 10 μl water droplets containing 2 mm solid inclusions in the shape of cube, when heated (up to 850 K) in combustion products of technical ethanol. Adding solid inclusions in water droplets allowed considerably decreasing (by 70%) their evaporation times. Also, the artificial irregularities (roughness and porosity) at the surfaces of solid inclusions were manufactured to increase heat transfer area. Such approach enabled to decrease evaporation times of heterogeneous liquid droplets in high-temperature gases by 40% (when comparing inclusions with artificial irregularities and smooth surface).

International audience; Measurements of the thermal conductivity of HFC-134a made in a coaxial cylinder cell operating in steady state are reported. Measurements were performed along several quasi-isotherms at temperatures ranging from the critical temperature Tc (374 K) to Tc + 150 K and in a pressure range from (0.1 to 40) MPa. Parameters of a background equation were determined from experimental data to analyze the critical enhancement of the thermal conductivity as a function of temperature and density. An analysis of the various sources of errors leads to an estimated uncertainty of the thermal conductivity data of ± 3 %.