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1.
Molecules ; 29(17)2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39275028

RESUMEN

The molar heat capacity of 1,4-bis(3-methylimidazolium-1-yl)butane bis(trifluoromethylsulfonyl)imide dicationic ionic compound ([C4(MIm)2][NTf2]2) has been studied over the temperature range from 6 to 350 K by adiabatic calorimetry. In the above temperature interval, this compound has been found to form crystal, liquid, and supercooled liquid. For [C4(MIm)2][NTf2]2, the temperature of fusion T°fus = (337.88 ± 0.01) K has been determined by the fractional melting experiments, the enthalpy of fusion ΔfusH° = (52.79 ± 0.28) kJ mol-1 has been measured using the calorimetric method of continuous energy input, and the entropy of fusion ΔfusS° = (156.2 ± 1.7) J K-1 mol-1 has also been evaluated. The standard thermodynamic functions of the studied dicationic ionic compound, namely, the heat capacity Cp°(T), the enthalpy [H°(T) - H°(0)], the entropy S°(T) and the Gibbs free energy [G°(T) - H°(0)] have been calculated on the basis of the experimental data for the temperature range up to 350 K. The results have been discussed and compared with those available in the literature and in the NIST Ionic Liquids Database (ILThermo) for monocationic ionic compounds.

2.
Artículo en Inglés | MEDLINE | ID: mdl-39231472

RESUMEN

Here a spin glass system with emergent planar ordered spin clusters is investigated. The mixed B-site pyrochlore Gd2ScNbO7has been synthesized and characterized through a variety of techniques, including x-ray diffraction, magnetic susceptibility, muon spin relaxation, heat capacity and neutron scattering. Despite a Curie-Weiss temperature of -3.93(3) K, indicating net antiferromagnetic interactions, no signs of long ranged magnetic ordering are found down to T = 0.3 K. Instead, a disordered magnetic state emerges with a small correlation length of 2.1(1) Angstroms of single tetrahedra. A RMC analysis of the polarized neutron scattering data reveals short-range antiferromagnetic order with emergent XY spin ordering similar to the parent pyrochlore compounds. Muon spin relaxation, and AC susceptibility measurements confirm that the magnetization condenses into a glass, with 10 % of the potential entropy missing in the specific heat. This magnetic ground state is similar to what is observed in Gd2Sn2O7just above the ordering temperature, without the eventual long-range ordering at low temperature. .

3.
Heliyon ; 10(16): e36064, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39229518

RESUMEN

High entropy alloys (HEAs) are alloys composed of five or more primary elements in equal or nearly equal proportions of atoms. In the present study, the thermophysical properties of the CoCrFeNiCu high entropy alloy (HEA) were investigated by a molecular dynamics (MD) method at nanoscale. The effects of the content of individual elements on lattice thermal conductivity k p were revealed, and the results suggested that adjusting the atomic content can be a way to control the lattice thermal conductivity of HEAs. The effects of temperature on k p were investigated quantitively, and a power-law relationship of k p with T -0.419 was suggested, which agrees with previous findings. The effects of temperature and the content of individual elements on volumetric specific heat capacity C v were also studied: as the temperature increases, the C v of all HEAs slightly decreases and then increases. The effects of atomic content on C v varied with the comprising elements. To further understand heat transfer mechanisms in the HEAs, the phonon density of states (PDOS) at different temperatures and varying atomic composition was calculated: Co and Ni elements facilitate the high-frequency vibration of phonons and the Cu environment weakens the heat transfer via low-frequency vibration of photons. As the temperature increases, the phonon mean free path (MFP) in the equiatomic CoCrFeNiCu HEA decreases, which may be attributed to the accelerated momentum of atoms and intensified collisions of phonons. The present research provides theoretical foundations for alloy design and have implications for high-performance alloy smelting.

4.
Arch Biochem Biophys ; 760: 110132, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39181382

RESUMEN

Differential Scanning Calorimetry (DSC) is a regular and powerful tool to measure the specific heat profile of various materials. Hydrogen bonds play a crucial role in stabilizing the three-dimensional structure of proteins. Naturally, information about the strength of hydrogen bonds is contained in the measured DSC profiles. Despite its obvious importance, there is no approach that would allow the extraction of such information from the heat capacity measurements. In order to connect the measured profile to microscopic properties of a polypeptide chain, a proper model is required to fit. Using recent advances in the Zimm-Bragg (ZB) theory of protein folding in water, we propose a new and efficient algorithm to process the DSC experimental data and to extract the H-bonding energy among other relevant constants. Thus, for the randomly picked set of 33 proteins, we have found a quite narrow distribution of hydrogen bonding energies from 1 to 8 kJ/mol with the average energy of intra-protein hydrogen bonds h¯=4.2±1.5 kJ/mol and the average energy of water-protein bonds as hps¯=3.8±1.5 kJ/mol. This is an important illustration of a tiny disbalance between the water-protein and intraprotein hydrogen bonds. Fitted values of the nucleation parameter σ belong to the range from 0.001 to 0.01, as expected. The reported method can be considered as complementary to the classical two-state approach and together with other parameters provides the protein-water and intraprotein H-bonding energies, not accessible within the two-state paradigm.


Asunto(s)
Rastreo Diferencial de Calorimetría , Enlace de Hidrógeno , Proteínas , Agua , Agua/química , Proteínas/química , Algoritmos , Pliegue de Proteína , Termodinámica , Modelos Moleculares
5.
Food Res Int ; 192: 114816, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147509

RESUMEN

Lipids are the key matrix for the presence of odorants in meat products. The formation mechanism of odorants of air-fried (AF) pork at 230 °C was elucidated from the perspectives of lipids and heat transfer using physicochemical analyses and multidimensional statistics. Twenty-nine key aroma compounds were identified, with pyrazines predominantly contributing to the roasty aroma of air-fried roasted pork. Untargeted lipidomics revealed 1184 lipids in pork during roasting, with phosphatidylcholine (PC), phosphatidylethanolamine (PE), and triglyceride (TG) being the major lipids accounting for about 60 % of the total lipids. TG with C18 acyl groups, such as TG 16:1_18:1_18:2 and TG 18:0_18:0_20:3, were particularly significant in forming the aroma of AF pork. The OPLS-DA model identified seven potential biomarkers that differentiate five roasting times, including PC 16:0_18:3 and 2-ethyl-3,5-dimethylpyrazine. Notably, a lower specific heat capacity and water activity accelerated heat transfer, promoting the formation and retention of odorants in AF pork.


Asunto(s)
Culinaria , Cromatografía de Gases y Espectrometría de Masas , Odorantes , Culinaria/métodos , Odorantes/análisis , Animales , Porcinos , Cromatografía de Gases y Espectrometría de Masas/métodos , Cromatografía Líquida de Alta Presión , Calor , Pirazinas/análisis , Lípidos/análisis , Productos de la Carne/análisis , Triglicéridos/análisis , Lipidómica/métodos , Carne de Cerdo/análisis
6.
Heliyon ; 10(15): e34762, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39145021

RESUMEN

The thermodynamic characteristics of a pair-interacting hole gas localized in a Ge/Si lens-shaped quantum dot are studied. The pair-interaction potential is modeled by the oscillator function, which depends on the distance between the particles. The analytical form of the spectra makes it possible to calculate the partition function in Boltzmann approximation. Based on the partition function mean and free energies, heat capacity and entropy of the interacting gas are calculated. Interaction between particles substantially changes the behavior of the thermodynamic properties in comparison with the non-interacting gas case. In particular, the gas undergoes a first-order phase transition driven by the height of the upper (or lower) section of QD, resulting in a changing symmetry of the lens-shaped QD.

7.
Heliyon ; 10(11): e31835, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38947454

RESUMEN

During the measurement of multiphase flow in low yield oil wells, the liquid volume will vary with the operating characteristics of the pumping unit. Using the pulsating characteristics of the up and down strokes of a pumping unit, the flow rate is measured when there is a flow rate on the up stroke, and the water content is measured when the fluid is stationary on the down stroke. In this paper, the heat transfer method is used to measure the water content of the oil water mixture during the down stroke process. At this time, the water content can be expressed as the instantaneous water content of the oil well. Firstly, the feasibility of measuring water content using heat transfer method is demonstrated theoretically, and then the temperature change of the heating probe PT300 is simulated. Finally, the actual temperature of PT300 is measured experimentally. Comparing the experimental value with the simulation value, the calculated measurement error is within 1.27 %, which indicates that the heat transfer method is feasible for measuring water content. Using the same single sensor to measure oil water two-phase flow using the pulsation characteristics of the up and down strokes of a pumping unit is a major innovation in this paper. And lays a foundation for the detection of multiphase flow using heat transfer methods. The successful implementation of the text heat transfer method for measuring water content has broken the previous situation of multiple sensor detection, simplified the structure of multiphase flow instruments, and extended the life of the instrument.

8.
Chemphyschem ; 25(16): e202400102, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-38923744

RESUMEN

The poor solubility of nonpolar compounds in water around room temperature is governed by a large and negative entropy change, whose molecular cause is still debated. Since the Frank and Evans original proposal in 1945, the large and negative entropy change is usually attributed to the formation of ordered structures in the hydration shell of nonpolar groups. However, the existence of such ordered structures has never been proven. The present study is aimed at providing available structural results and thermodynamic arguments disproving the existence of ordered structures in the hydration shell of nonpolar groups.

9.
Micromachines (Basel) ; 15(6)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38930641

RESUMEN

Among the different techniques for monitoring the flow rate of various fluids, thermal flow sensors stand out for their straightforward measurement technique. However, the main drawback of these types of sensors is their dependency on the thermal properties of the medium, i.e., thermal conductivity (k), and volumetric heat capacity (ρcp). They require calibration whenever the fluid in the system changes. In this paper, we present a single hot wire suspended above a V-groove cavity that is used to measure k and ρcp through DC and AC excitation for both pure gases and binary gas mixtures, respectively. The unique characteristic of the proposed sensor is its independence of the flow velocity, which makes it possible to detect the medium properties while the fluid flows over the sensor chip. The measured error due to fluctuations in flow velocity is less than ±0.5% for all test gases except for He, where it is ±6% due to the limitations of the measurement setup. The working principle and measurement results are discussed.

10.
Angew Chem Int Ed Engl ; 63(34): e202406616, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-38771295

RESUMEN

Hybrid layered double perovskites (HLDPs), representing the two-dimensional manifestation of halide double perovskites, have elicited considerable interest owing to their intricate chemical bonding hierarchy and structural diversity. This intensified interest stems from the diverse options available for selecting alternating octahedral coordinated trivalent [M(III)] and monovalent metal centers [M(I)], along with the distinctive nature of the cationic organic amine located between the layers. Here, we have synthesized three new compounds with general formula (R'/R'')4/2M(III)M(I)Cl8; where R'=C3H7NH3 (i.e. 3N) and R''=NH3C4H8NH3 (i.e. 4N4); M(III)=In3+ or Ru3+; M(I)=Cu+ by simple solution-based acid precipitation method. The structural analysis reveals that (4N4)2CuInCl8 and (4N4)2CuRuCl8 adopt the layered Dion Jacobson (DJ) structure, whereas (3N)4CuInCl8 exhibits layered Ruddlesden Popper (RP) structure. The alternative octahedra within the inorganic layer display distortions and tilting. Three compounds show temperature-dependent structural phase transitions where changes in the staking of inorganic layer, extent of octahedral tilting and reorientation of organic spacers with temperature have been noticed. We have achieved ultralow lattice thermal conductivity (κL) in the HLDPs in the 2 to 300 K range, marking a distinctive feature within the realm of HLDP systems. The RP-HLDP compound, (3N)4CuInCl8, demonstrates anisotropy in κL while measured parallel and perpendicular to layer stacking, showcasing ultralow κL of 0.15 Wm-1K-1 at room temperature, which is one of the lowest values obtained among Pb-free metal halide perovskite. The observed ultralow κL in three new HLDPs is attributed to significant lattice anharmonicity arising from the chemical bonding heterogeneity and soft crystal structure, which resulted in low-energy localized optical phonon modes that suppress heat-carrying acoustic phonons.

11.
J Mol Biol ; 436(13): 168626, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38810774

RESUMEN

The thermodynamics of secondary p53 binding sites on MDM2 and MDMX were evaluated using p53 peptides containing residues 16-29, 17-35, and 1-73. All the peptides had large, negative heat capacity (ΔCp), consistent with the burial of p53 residues F19, W23, and L26 in the primary binding sites of MDM2 and MDMX. MDMX has a higher affinity and more negative ΔCp than MDM2 for p5317-35, which is due to MDMX stabilization and not additional interactions with the secondary binding site. ΔCp measurements show binding to the secondary site is inhibited by the disordered tails of MDM2 for WT p53 but not a more helical mutant where proline 27 is changed to alanine. This result is supported by all-atom molecular dynamics simulations showing that p53 residues 30-35 turn away from the disordered tails of MDM2 in P27A17-35 and make direct contact with this region in p5317-35. Molecular dynamics simulations also suggest that an intramolecular methionine-aromatic motif found in both MDM2 and MDMX structurally adapts to support multiple p53 binding modes with the secondary site. ΔCp measurements also show that tighter binding of the P27A mutant to MDM2 and MDMX is due to increased helicity, which reduces the energetic penalty associated with coupled folding and binding. Our results will facilitate the design of selective p53 inhibitors for MDM2 and MDMX.


Asunto(s)
Proteínas de Ciclo Celular , Simulación de Dinámica Molecular , Proteínas Proto-Oncogénicas c-mdm2 , Proteínas Proto-Oncogénicas , Termodinámica , Proteína p53 Supresora de Tumor , Humanos , Sitios de Unión , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Unión Proteica , Conformación Proteica , Proteínas Proto-Oncogénicas/química , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-mdm2/química , Proteínas Proto-Oncogénicas c-mdm2/genética , Proteína p53 Supresora de Tumor/química , Proteína p53 Supresora de Tumor/genética
12.
Molecules ; 29(9)2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38731621

RESUMEN

In the selection and design of ionic liquids (ILs) for various applications, including heat transfer fluids, thermal energy storage materials, fuel cells, and solvents for chemical processes, heat capacity is a key thermodynamic property. While several attempts have been made to develop predictive models for the estimation of the heat capacity of ILs in their liquid phase, none so far have been reported for the ILs' solid crystal phase. This is particularly important for applications where ILs will be used for thermal energy storage in the solid phase. For the first time, a model has been developed and used for the prediction of crystal phase heat capacity based on extending and modifying a previously developed hybrid group contribution model (GCM) for liquid phase heat capacity. A comprehensive database of over 5000 data points with 71 unique crystal phase ILs, comprising 42 different cations and 23 different anions, was used for parameterization and testing. This hybrid model takes into account the effect of the anion core, cation core, and subgroups within cations and anions, in addition to the derived indirect parameters that reflect the effects of branching and distribution around the core of the IL. According to the results, the developed GCM can reliably predict the crystal phase heat capacity with a mean absolute percentage error of 6.78%. This study aims to fill this current gap in the literature and to enable the design of ILs for thermal energy storage and other solid phase applications.

13.
Sci Rep ; 14(1): 11252, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755227

RESUMEN

This study employs ab initio calculations based on density functional theory (DFT) to investigate the structural properties, 1H-NMR spectra, and vibrational spectra of methane sulfonic acid (MSA) at low degree of hydration. The findings reveal that energetically stable structures are formed by small clusters consisting of one or two MSA molecules (m = 1 and 2) and one or two water molecules in (MSA)m·(H2O)n (m = 1-2 and n = 1-5).These stable structures arise from the formation of strong cyclic hydrogen bonds between the proton of the hydroxyl (OH) group in MSA and the water molecules. However, clusters containing three or more water molecules (n > 2) exhibit proton transfer from MSA to water, resulting in the formation of ion-pairs composed of CH3SO3- and H3O+species. The measured 1H-NMR spectra demonstrate the presence of hydrogen-bonded interactions between MSA and water, with a single MSA molecule interacting with water molecules. This interaction model accurately represents the hydrogen bonding network, as supported by the agreement between the experimental and calculated NMR chemical shift results.

14.
Molecules ; 29(10)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38792042

RESUMEN

1,3,5-Tris-(α-naphthyl)benzene is an organic non-electrolyte with notable stability of an amorphous phase. Its glassy and supercooled liquid states were previously studied by spectroscopic and calorimetric methods. Despite the continuing interest in its amorphous state and, particularly, vapor-deposited glasses, the thermodynamic parameters of the vaporization of 1,3,5-tris-(α-naphthyl)benzene have not been obtained yet. Likewise, the reliable evaluation of the thermodynamic parameters of fusion below the melting point, required to establish the thermodynamic state of its glass, is still an unsolved problem. In this work, the heat capacities of crystalline and liquid phases, the temperature dependence of the saturated vapor pressures, fusion and vaporization enthalpies were determined using differential and fast scanning calorimetry and were verified using the estimates based on solution calorimetry. The structural features of 1,3,5-tris-(α-naphthyl)benzene are discussed based on the computations performed and the data on the molecular refractivity. The consistency between the values obtained by independent techniques was demonstrated.

15.
Molecules ; 29(10)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38792189

RESUMEN

A novel ternary eutectic salt, NaNO3-KNO3-Na2SO4 (TMS), was designed and prepared for thermal energy storage (TES) to address the issues of the narrow temperature range and low specific heat of solar salt molten salt. The thermo-physical properties of TMS-2, such as melting point, decomposition temperature, fusion enthalpy, density, viscosity, specific heat capacity and volumetric thermal energy storage capacity (ETES), were determined. Furthermore, a comparison of the thermo-physical properties between commercial solar salt and TMS-2 was carried out. TMS-2 had a melting point 6.5 °C lower and a decomposition temperature 38.93 °C higher than those of solar salt. The use temperature range of TMS molten salt was 45.43 °C larger than that of solar salt, which had been widened about 13.17%. Within the testing temperature range, the average specific heat capacity of TMS-2 (1.69 J·K-1·g-1) was 9.03% higher than that of solar salt (1.55 J·K-1·g-1). TMS-2 also showed higher density, slightly higher viscosity and higher ETES. XRD, FTIR and Raman spectra SEM showed that the composition and structure of the synthesized new molten salt were different, which explained the specific heat capacity increasing. Molecular dynamic (MD) simulation was performed to explore the different macroscopic properties of solar salt and TMS at the molecular level. The MD simulation results suggested that cation-cation and cation-anion interactions became weaker as the temperature increased and the randomness of molecular motion increased, which revealed that the interaction between the cation cluster and anion cluster became loose. The stronger interaction between Na-SO4 cation-anion clusters indicated that TMS-2 molten salt had a higher specific heat capacity than solar salt. The result of the thermal stability analysis indicated that the weight losses of solar salt and TMS-2 at 550 °C were only 27% and 53%, respectively. Both the simulation and experimental study indicated that TMS-2 is a promising candidate fluid for solar power generation systems.

16.
Comput Biol Chem ; 110: 108081, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38677012

RESUMEN

Protein stability is a critical aspect of molecular biology and biochemistry, hinges on an intricate balance of thermodynamic and structural factors. Determining protein stability is crucial for understanding and manipulating biological machineries, as it directly correlated with the protein function. Thus, this study delves into the intricacies of protein stability, highlighting its dependence on various factors, including thermodynamics, thermal conditions, and structural properties. Moreover, a notable focus is placed on the free energy change of unfolding (ΔGunfolding), change in heat capacity (ΔCp) with protein structural transition, melting temperature (Tm) and number of disulfide bonds, which are critical parameters in understanding protein stability. In this study, a machine learning (ML) predictive model was developed to estimate these four parameters using the primary sequence of the protein. The shortfall of available tools for protein stability prediction based on multiple parameters propelled the completion of this study. Convolutional Neural Network (CNN) with multiple layers was adopted to develop a more reliable ML model. Individual predictive models were prepared for each property, and all the prepared models showed results with high accuracy. The R2 (coefficient of determination) of these models were 0.79, 0.78, 0.92 and 0.92, respectively, for ΔG, ΔCp, Tm and disulfide bonds. A case study on stability analysis of two homologous proteins was presented to validate the results predicted through the developed model. The case study included in silico analysis of protein stability using molecular docking and molecular dynamic simulations. This validation study assured the accuracy of each model in predicting the stability associated properties. The alignment of physics-based principles with ML models has provided an opportunity to develop a fast machine learning solution to replace the computationally demanding physics-based calculations used to determine protein stability. Furthermore, this work provided valuable insights into the impact of mutation on protein stability, which has implications for the field of protein engineering. The source codes are available at https://github.com/Growdeatechnology.


Asunto(s)
Simulación de Dinámica Molecular , Redes Neurales de la Computación , Estabilidad Proteica , Proteínas , Proteínas/química , Termodinámica , Aprendizaje Automático
17.
Nano Lett ; 24(13): 4038-4043, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38511834

RESUMEN

Specific heat capacity is one of the most fundamental thermodynamic properties of materials. In this work, we measured the specific heat capacity of PbSe nanocrystals with diameters ranging from 5 to 23 nm, and its value increases significantly from 0.2 to 0.6 J g-1 °C-1. We propose a mass assignment model to describe the specific heat capacity of nanocrystals, which divides it into four parts: electron, inner, surface, and ligand. By eliminating the contribution of ligand and electron specific heat capacity, the specific heat capacity of the inorganic core is linearly proportional to its surface-to-volume ratio, showing the size dependence. Based on this linear relationship, surface specific heat capacity accounts for 40-60% of the specific heat capacity of nanocrystals with size decreasing. It can be attributed to the uncoordinated surface atoms, which is evidenced by the appearance of extra surface phonons in Raman spectra and ab initio molecular dynamics (AIMD) simulations.

18.
Molecules ; 29(5)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38474622

RESUMEN

An extensive thermodynamic study of N-methylformamide (CAS RN: 123-39-7) and N,N-dimethylformamide (CAS RN: 68-12-2), is presented in this work. The liquid heat capacities of N-methylformamide were measured by Tian-Calvet calorimetry in the temperature interval (250-300) K. The vapor pressures for N-methylformamide and N,N-dimethylformamide were measured using static method in the temperature range 238 K to 308 K. The ideal-gas thermodynamic properties were calculated using a combination of the density functional theory (DFT) and statistical thermodynamics. A consistent thermodynamic description was developed using the method of simultaneous correlation, where the experimental and selected literature data for vapor pressures, vaporization enthalpies, and liquid phase heat capacities and the calculated ideal-gas heat capacities were treated together to ensure overall thermodynamic consistency of the results. The resulting vapor pressure equation is valid from the triple point to the normal boiling point temperature.

19.
Heliyon ; 10(5): e27134, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38444504

RESUMEN

This study reports the synthesis of type-I Ba8CuNi2.5Ga10Si33.5 clathrate as a single crystal by the flux method and physical properties investigations such as structural, chemical, magnetic, and thermal properties. Structural refinements indicate Ba atoms are situated at 2a and 6d positions with mixed occupancy across framework sites. Raman spectroscopy assessed host-guest interactions, while the compound's morphology and composition were investigated by the scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS) analyses. Magnetic properties revealed ferromagnetic interactions characterized by a positive Weiss constant and weak ferromagnetic hysteresis. The compound's metallic nature is evidenced by increased resistivity with temperature. The Sommerfeld coefficient, estimated at 12.59 mJ mol-1 K-2 from heat capacity data, alongside a pronounced peak around 15 K in the Cp/T3 vs T plot, suggests an Einstein contribution in heat capacity.

20.
Materials (Basel) ; 17(4)2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38399205

RESUMEN

This study critically reviews the key aspects of nanoparticles and their impact on molten salts (MSs) for thermal energy storage (TES) in concentrated solar power (CSP). It then conducts a comprehensive analysis of MS nanofluids, focusing on identifying the best combinations of salts and nanoparticles to increase the specific heat capacity (SHC) efficiently. Various methods and approaches for the synthesis of these nanofluids are explained. The article presents different experimental techniques used to characterize nanofluids, including measuring the SHC and thermal conductivity and analyzing particle dispersion. It also discusses the challenges associated with characterizing these nanofluids. The study aims to investigate the underlying mechanisms behind the observed increase in SHC in MS nanofluids. Finally, it summarizes potential areas for future research, highlighting crucial domains for further investigation and advancement.

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