{"title":"Peculiar Nonideal Behavior of Deeply Supercooled Equimolar Binary Mixture of Water and Ethylene Glycol: DSC, Densitometry, and Rheology Study","authors":"Matthew Leonard, Bratoljub H. Milosavljevic","doi":"10.1007/s10765-026-03838-z","DOIUrl":"10.1007/s10765-026-03838-z","url":null,"abstract":"<div><p>An equimolar binary mixture of water and ethylene glycol (EWEGM) exhibits an atypical thermodynamic behavior, <i>i.e.</i>, regular crystallization at − 43 °C occurs only when the sample is properly seeded; otherwise, a glass transition (T<sub>g</sub>) is observed at − 123 °C even at cooling rates as low as 0.1 K min⁻<sup>1</sup>, as revealed through our DSC measurements. No crystallization was detected when the sample was subjected to mechanical stress by forcing it to flow through a capillary viscometer at − 75 °C. The addition of 0.3 M (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub>, or 3 mM Al(OH)<sub>3</sub>, or 1 mM AgI, in the form of nanocrystals, to EWEGM does not promote the crystallization on cooling either. The density of EWEGM exceeds that of the ideal mixture (defined as the weighted linear combination of the densities of pure water and ethylene glycol) throughout the explored temperature range (+ 40 to − 75 °C), consistent with the measured negative enthalpy of mixing (Δ<sub>mix</sub>H = − 16.6 ± 0.3 J g⁻<sup>1</sup>). The isobaric heat capacity was measured from + 20 to − 150 °C and was found to exceed the ideal value by 6 % in the temperature interval 0 to + 20 °C. The viscosity of EWEGM shows a pronounced deviation from Arrhenius behavior across the entire temperature interval investigated (+ 40 to − 115 °C); EWEGM can be classified as a moderately fragile liquid (<i>m</i> = 70). The relationship ln(<i>η</i>/<i>η</i>₀) = f(T) is accurately captured by the VFT model, and the resulting parameters are discussed in detail. In addition, mode‑coupling theory and the Adam–Gibbs model were applied to obtain deeper insight into the temperature dependence of the mixture’s peculiar thermophysical properties, and the corresponding analysis is included as well.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"47 10","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-026-03838-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149007444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Premnath, P. Chandrasekaran, M. Kamaraj, A. Sathishkumar
{"title":"Hybrid Nano-Enhanced PCMs in Finned Spherical Capsules for Cold Thermal Energy Storage","authors":"D. Premnath, P. Chandrasekaran, M. Kamaraj, A. Sathishkumar","doi":"10.1007/s10765-026-03840-5","DOIUrl":"10.1007/s10765-026-03840-5","url":null,"abstract":"<div><p>This study experimentally investigates the thermal performance of nano-enhanced phase change materials (NEPCMs) for cold thermal energy storage using spherical capsules with and without internal copper fins. Deionized (DI) water was enhanced with graphene nanoplatelets (GNP), Fe<sub>2</sub>O<sub>3</sub>, and their hybrid combination at a total concentration of 0.1 wt%. The NEPCMs were characterized in terms of dispersion stability, thermal conductivity, viscosity, latent heat, and solidification behavior. Solidification experiments were conducted at four radial locations corresponding to 53 %, 78 %, 89 %, and 100 % of the capsule radius, with the heat transfer fluid maintained at − 5 °C and complete solidification identified at − 1.5 °C. The hybrid NEPCM showed the highest thermal conductivity of 0.784 W·m<sup>−1</sup>·K, representing a 38 % enhancement over DI water, while its viscosity increased to 1.03 mPa·s. The freezing latent heat increased from − 290.2 J·g<sup>−1</sup> to − 314.5 J·g<sup>−1</sup>, while the freezing peak temperature shifted from − 21.6 °C to − 18.7 °C. The hybrid NEPCM reduced the total solidification time by 29 % compared with DI water without fins and by 40.8 % when internal fins were used. The results show that the combined use of hybrid nanoparticles and internal fins improves thermal conductivity and accelerates PCM solidification, providing an effective approach for cold thermal energy storage.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"47 10","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149007437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sofia Polychroniadou, Konstantinos D. Antoniadis, Marc J. Assael, Ian H. Bell
{"title":"Correction to: A Reference Correlation for the Viscosity of Krypton from Entropy Scaling","authors":"Sofia Polychroniadou, Konstantinos D. Antoniadis, Marc J. Assael, Ian H. Bell","doi":"10.1007/s10765-026-03844-1","DOIUrl":"10.1007/s10765-026-03844-1","url":null,"abstract":"","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"47 10","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149007442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Density and Molar Volume of CaO–SiO2–FeO Melts Measured by Electrostatic Levitation Aboard the International Space Station","authors":"Yusaku Seimiya, Masahito Watanabe, Takehiko Ishikawa, Chihiro Koyama, Yuki Watanabe","doi":"10.1007/s10765-026-03835-2","DOIUrl":"10.1007/s10765-026-03835-2","url":null,"abstract":"<div><p>The densities of CaO–SiO<sub>2</sub>–FeO melts were measured under microgravity conditions using the Electrostatic Levitation Furnace aboard the International Space Station (ISS-ELF). The nominal FeO contents were 20, 60, and 80 mass% (CS20F, CS60F, and CS80F, respectively), with CaO and SiO<sub>2</sub> comprising the balance in a 1:1 mass ratio. Density was calculated from the sample mass and the droplet volume determined using shadow images recorded during cooling. For all compositions, the density decreased approximately linearly with increasing temperature. At a given temperature, the density increased with increasing FeO-equivalent content. The maximum relative expanded uncertainty in the density was 3.46 %, with a coverage factor of <i>k</i> = 2. After the experiments, the recovered samples were analyzed using scanning electron microscopy–energy-dispersive X-ray spectroscopy. Molar volumes were calculated from the measured densities using compositions derived from the measured Ca, Si, and Fe contents, and they were compared with literature data and an additive reference at approximately 1400 °C. The molar volume decreased from CS20F to CS60F and changed only slightly between CS60F and CS80F. The molar volumes of CS20F and CS60F were close to the additive reference, whereas that of CS80F showed a clear positive deviation.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"47 10","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10765-026-03835-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149007443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dennis Alt, Bennet Hopp, Jens Staubach, Hans Hasse, Simon Stephan
{"title":"High-Pressure Density Measurements and Modeling of Hydrocarbons: 1-Hexene, 2, 4-Dimethylhexane, 2,2,4-Trimethylpentane, and n-Heptane","authors":"Dennis Alt, Bennet Hopp, Jens Staubach, Hans Hasse, Simon Stephan","doi":"10.1007/s10765-026-03823-6","DOIUrl":"10.1007/s10765-026-03823-6","url":null,"abstract":"<div><p>Liquid densities of the hydrocarbons 1-hexene, 2,4-dimethylhexane, 2,2,4-trimethylpentane, and <i>n</i>-heptane were measured over a wide range of temperatures (293.15 K to 393.15 K) and pressures (up to 120 MPa), substantially extending the state range covered by previously available literature data. The density data were modeled using both an empirical correlation as well as a molecular-based equation of state (EOS). For each substance, an empirical <i>Tammann–Tait</i> correlation was developed that reproduces the new measurements with an average absolute deviation (AAD) of about 0.01%. Comparison with literature data shows good agreement for all four substances. Liquid densities calculated from the SAFT-VR Mie EOS were benchmarked against both the new data and literature data, yielding deviations typically below 0.4% which supports the predictive capability of this EOS across the studied conditions.\u0000</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"47 9","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13547189/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148904836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Measurement and Thermodynamic Modeling of Thermophysical Properties for Binary Mixtures of 2-Chloropropane with Diethyl Ether, Diisopropyl Ether, and Methyl Tert-Butyl Ether at Various Temperatures and Atmospheric Pressure","authors":"Linda Boussaid, Fouzia Amireche, Ariel Hernández","doi":"10.1007/s10765-026-03831-6","DOIUrl":"10.1007/s10765-026-03831-6","url":null,"abstract":"<div><p>Densities, dynamic viscosities, and refractive indices were experimentally determined for the binary systems (2-chloropropane + diethyl ether, 2-chloropropane + diisopropyl ether, and 2-chloropropane + methyl tert-butyl ether) over the entire composition range, at five temperatures from 283.15 K to 303.15 K and atmospheric pressure. To the best of our knowledge, no thermophysical data have been previously reported for these three binary systems. From the experimental measurements, the excess molar volume (<span>(V^{E})</span>), excess refractive index (<span>(n_{D}^{E})</span>), and viscosity deviation (<span>(Delta eta )</span>) were derived and correlated as a function of composition using the Redlich–Kister equation, with the number of adjustable parameters selected according to Fisher’s test. For the three systems, <span>(V^{E})</span>, <span>(n_{D}^{E})</span>, and <span>(Delta eta )</span> were found to be negative over the whole composition and temperature range, indicating the existence of specific dipole–dipole and weak Cl<span>(cdots )</span>O halogen-bond-type interactions between 2-chloropropane and the ether molecules, together with an efficient molecular packing effect. In addition, the PC-SAFT equation of state was applied to model the density and excess molar volume of the three mixtures, using a predictive approach (<span>(k_{ij}=0)</span>) and a fitted approach in which the binary interaction parameter was regressed against the experimental <span>(V^{E})</span> data. The new experimental data and modeling results reported in this work provide a valuable contribution toward the thermophysical characterization of chloroalkane + ether systems, relevant for process design and simulation in the chemical and petrochemical industries</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"47 9","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Measurement and Thermodynamic Modeling of Thermophysical Properties for Binary Mixtures of 2-Chloropropane with Diethyl Ether, Diisopropyl Ether, and Methyl Tert-Butyl Ether at Various Temperatures and Atmospheric Pressure","authors":"Linda Boussaid, Fouzia Amireche, Ariel Hernández","doi":"10.1007/s10765-026-03831-6","DOIUrl":"10.1007/s10765-026-03831-6","url":null,"abstract":"<div><p>Densities, dynamic viscosities, and refractive indices were experimentally determined for the binary systems (2-chloropropane + diethyl ether, 2-chloropropane + diisopropyl ether, and 2-chloropropane + methyl tert-butyl ether) over the entire composition range, at five temperatures from 283.15 K to 303.15 K and atmospheric pressure. To the best of our knowledge, no thermophysical data have been previously reported for these three binary systems. From the experimental measurements, the excess molar volume (<span>(V^{E})</span>), excess refractive index (<span>(n_{D}^{E})</span>), and viscosity deviation (<span>(Delta eta )</span>) were derived and correlated as a function of composition using the Redlich–Kister equation, with the number of adjustable parameters selected according to Fisher’s test. For the three systems, <span>(V^{E})</span>, <span>(n_{D}^{E})</span>, and <span>(Delta eta )</span> were found to be negative over the whole composition and temperature range, indicating the existence of specific dipole–dipole and weak Cl<span>(cdots )</span>O halogen-bond-type interactions between 2-chloropropane and the ether molecules, together with an efficient molecular packing effect. In addition, the PC-SAFT equation of state was applied to model the density and excess molar volume of the three mixtures, using a predictive approach (<span>(k_{ij}=0)</span>) and a fitted approach in which the binary interaction parameter was regressed against the experimental <span>(V^{E})</span> data. The new experimental data and modeling results reported in this work provide a valuable contribution toward the thermophysical characterization of chloroalkane + ether systems, relevant for process design and simulation in the chemical and petrochemical industries</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"47 9","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Thermophysical Properties and CO2 Solubility in Binary and Ternary Mixtures of Polyethylene Glycol 400, Ethylene Glycol, and Thymol–Camphor Deep Eutectic Solvent","authors":"Ali Reza Harifi-Mood, Mohammad Karimi","doi":"10.1007/s10765-026-03829-0","DOIUrl":"10.1007/s10765-026-03829-0","url":null,"abstract":"<div><p>The solubility of carbon dioxide (CO<sub>2</sub>) in binary and ternary solvent mixtures composed of polyethylene glycol 400 (PEG 400), ethylene glycol (EG), and a thymol–camphor-based hydrophobic deep eutectic solvent (TC-HDES) was experimentally investigated at temperatures of 298.15 and 308.15 K and pressures up to 0.5 MPa. In addition, selected thermophysical properties, including density, were measured to support the analysis of gas–liquid equilibrium behavior. All solvent compositions studied for CO<sub>2</sub> absorption were confirmed to remain in the homogeneous liquid phase under the investigated conditions. Henry’s law constants indicate that PEG 400 exhibits the highest CO<sub>2</sub> solubility (4.53 MPa), followed by the TC-HDES (10.3 MPa), while EG shows significantly lower solubility (43.8 MPa). To gain insight into solute–solvent interactions at the molecular level, the preferential solvation model was applied to the experimental data. The results suggest that PEG 400 preferentially occupies the solvation shell of CO<sub>2</sub> in both binary and ternary mixtures, dominating over EG and TC-HDES. This behavior is attributed to the multi-oxyethylene structure of PEG 400, which promotes favorable interactions with CO<sub>2</sub>. The combined experimental and modeling results provide useful insight into the design of mixed-solvent systems for CO<sub>2</sub> capture, enabling improved performance through appropriate selection of solvent composition, while considering practical constraints such as viscosity and cost.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"47 9","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Direct Identification of the Spectral Effective Radiative Characteristics of Semi-transparent Insulators for Macroscopic Transient Coupled Conduction–Radiation Simulation","authors":"Loïc Seyer, Cyril Daoût, Denis Rochais, Olivier Rozenbaum","doi":"10.1007/s10765-026-03824-5","DOIUrl":"10.1007/s10765-026-03824-5","url":null,"abstract":"<div><p>A Monte Carlo Ray Tracing (MCRT) homogenization is proposed to compute the spectral effective radiative and optical characteristics (<span>(alpha _textrm{eff})</span>, <span>(sigma _textrm{eff})</span>, <span>(g_textrm{eff})</span>, <span>(n_textrm{eff})</span>, <span>(k_textrm{eff})</span>) of real heterogeneous semi-transparent media. Performed on statistically representative numerical microstructures, with the knowledge of the intrinsic indices of the constituents identified from normal-hemispherical reflectance and transmittance measurements, the method delivers all five characteristics in a single forward pass, with no further inversion: in particular, the asymmetry factor is read directly from the ray statistics, and the effective refractive index is obtained by a numerical time-of-flight method free of any external assumption. Because it operates on the microstructure itself, the approach assumes no particular object shape. It is demonstrated on two real aluminosilicate fibrous insulators, MAFTEC 96 and FOX. The practical relevance of the identified characteristics is illustrated by coupled conductive–radiative simulations compared against transient temperature measurements for both materials. The comparison shows that the identified characteristics capture the radiative contribution to heat transfer, and that a gray diffusion (Rosseland) approximation remains insufficient even for thick semi-transparent media, so that full spectral coupling is needed to reproduce the experimental response.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"47 9","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Thermophysical Properties and CO2 Solubility in Binary and Ternary Mixtures of Polyethylene Glycol 400, Ethylene Glycol, and Thymol–Camphor Deep Eutectic Solvent","authors":"Ali Reza Harifi-Mood, Mohammad Karimi","doi":"10.1007/s10765-026-03829-0","DOIUrl":"10.1007/s10765-026-03829-0","url":null,"abstract":"<div><p>The solubility of carbon dioxide (CO<sub>2</sub>) in binary and ternary solvent mixtures composed of polyethylene glycol 400 (PEG 400), ethylene glycol (EG), and a thymol–camphor-based hydrophobic deep eutectic solvent (TC-HDES) was experimentally investigated at temperatures of 298.15 and 308.15 K and pressures up to 0.5 MPa. In addition, selected thermophysical properties, including density, were measured to support the analysis of gas–liquid equilibrium behavior. All solvent compositions studied for CO<sub>2</sub> absorption were confirmed to remain in the homogeneous liquid phase under the investigated conditions. Henry’s law constants indicate that PEG 400 exhibits the highest CO<sub>2</sub> solubility (4.53 MPa), followed by the TC-HDES (10.3 MPa), while EG shows significantly lower solubility (43.8 MPa). To gain insight into solute–solvent interactions at the molecular level, the preferential solvation model was applied to the experimental data. The results suggest that PEG 400 preferentially occupies the solvation shell of CO<sub>2</sub> in both binary and ternary mixtures, dominating over EG and TC-HDES. This behavior is attributed to the multi-oxyethylene structure of PEG 400, which promotes favorable interactions with CO<sub>2</sub>. The combined experimental and modeling results provide useful insight into the design of mixed-solvent systems for CO<sub>2</sub> capture, enabling improved performance through appropriate selection of solvent composition, while considering practical constraints such as viscosity and cost.</p></div>","PeriodicalId":598,"journal":{"name":"International Journal of Thermophysics","volume":"47 9","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}