Low Temperature Region Research Articles

Historical simulations of temperature and precipitation from the CORDEX Africa model in the Wabi Shebele Basin

Rising global temperatures and shifting precipitation patterns have significant socio-economic consequences if not properly studied and predicted. Regional climate models (RCMs) are utilized to assess local-scale climate change. However, the reliability of individual models must be validated due to inherent limitations and methodological constraints. This study evaluates the performance of CORDEX Africa RCMs using observed rainfall and air temperature data from 1986 to 2005. Model performance was evaluated using statistical indicators such as bias, RMSE, r, MAE, and a concise plot of the statistical indicators which is Taylor’s diagram. In rainfall simulation, the RACMO22T performed admirably in the upper parts of the basin (region of high rainfall and cold temperature) and lower regions of the basin (region of low rainfall and hot temperature) with bias −8.64% and 6.19% respectively. HIRHAM5 and CCLM4-8 simulate well the maximum temperature in the upper parts with biases of (0.14 °C and −0.14 °C respectively), whereas RCA4 is well performed in the lower parts of the basin. CCLM4-8 is good for minimum temperature simulation in the upper parts, but HIRHAM5 and RCA4 are good in the lower parts of the basin. In rainfall simulation, all models are slightly good in dry months than in wet. All models underestimated the maximum temperature and overestimated the minimum temperature in the study area as compared to the observed.

Biochar obtained from alkaline earth metal-treated mushroom residue: Thermal behavior and methyl orange adsorption capability

To achieve the resource utilization of edible fungi residue and obtain efficient adsorbents for treating dyeing wastewater, biochars were prepared from mushroom residue (MR) with the introduction of alkaline-earth metals (AEMs) and used for methyl orange (MO) wastewater treatment. The thermal behavior of the AEM-treated MR was analyzed using thermogravimetric analysis. The physicochemical properties of the biochars obtained from AEM-treated MR (MRCs) were characterized using Fourier transform infrared spectroscopy, laser particle size analyzer, N2 adsorption/desorption, and scanning electron microscopy. The adsorption performance of MRCs on MO was also investigated. The involvement of AEMs was found to obviously move the main pyrolysis zone of MR to a low temperature region and reduce the temperature corresponding to the maximum weight loss rate and activation energy, which is highly dependent on the concentration of AEMs, the anion and cationic species of the AEMs. Moreover, the addition of AEMs resulted in a decrease in oxygen-containing functional groups (-OH, CO, or C–O), a weakening of surface negative charges, an enhancement in aromatic functional groups, and an increase in specific surface area of the MRCs. The adsorption performance of MO on MRCs was significantly improved with the introduction of AEMs as well. Among them, MR pre-treated with 5 mmol/g MgCl2 (MR-MgCl2-5) shows the lowest temperature corresponding to the maximum weight loss rate and the lowest activation energy of 278.52 °C and 4.28 kJ/mol, respectively. The biochar prepared from MR-MgCl2-5 under 400 °C (MR-MgCl2-5-400C) has the weakest surface negative charge and the highest adsorption capacity for MO. The adsorption isotherms, adsorption kinetics, and thermodynamic analysis results showed that the adsorption of MO on MR-MgCl2-5-400C was a spontaneous, chemically dominant monolayer adsorption, with a theoretical maximum adsorption capacity of 81.30 mg/g. This study suggests that AEMs treatment, especially with 5 mmol/g MgCl2, can readily transform edible fungi residue into a low-cost, high-efficient dyeing wastewater adsorbent.

Study on thermal deformation constitutive model of NiCoFeAlCrMo high-entropy alloy with FCC / L12 coherent structure

Due to its multi-principal component characteristics, high-entropy alloys exhibit excellent comprehensive mechanical properties and become a new generation of engineering structure alternative materials. At present, a single constitutive model is used to describe the change of flow stress in the study of hot deformation behavior of high-entropy alloys, and there are some problems such as inaccurate prediction accuracy or inapplicability of the model in some hot processing intervals. In this paper, three different constitutive models are combined to fully consider the applicability of the model in different temperature ranges, and the change of flow stress behavior is accurately described, which is of great significance for subsequent deformation mechanism research, hot processing process optimization, numerical simulation and so on. Thermal compression experiments on cast Ni28.5Co18.6Fe18.2Al16.3Cr10.5Mo4 Ti2.3Nb0.6W0.9C0.2 high-entropy alloy were carried out using a Gleeble-3800 thermal simulation tester with deformation temperatures in the range from 900 ℃ to 1150 ℃ and strain rates from 0.001 s−1 to 1 s−1. The constitutive relationships between true stress and strain, temperature and strain rate were established, while the heat deformation process of this alloy under different deformation conditions by Arrhennius, Modified Johnson-Cook and Modified Fields-Backofen models were characterized. The results indicate that Arrenius model describe the rheological behavior of the alloy better in a wider temperature range and at a wider strain rate range. Comparatively, the model shows the highest prediction accuracy in the high-temperature region and slightly lower accuracy in the mesothermal and low-temperature regions. The modified J-C and F-B models have better prediction accuracy in the low-temperature and medium-temperature regions, respectively. Due to the different deformation conditions, dislocation configurations such as dislocation tangles, dislocation networks, and subcrystalline junctions can be observed in the plastic deformation region. The dislocation density of this alloy increases with increasing strain rate and decreasing deformation temperature after deformation.

Rheological Properties and Kinetics of Gelation of Binary Polymers between Xanthan Gum and Locust Bean Gum.

The synergistic interaction and gelling kinetics between xanthan gum (XG) and locust bean gum (LBG) at different mass ratios (XG/LBG 9:1, 7:3, 5:5, 3:7, 1:9) were investigated using a rheometer. The results showed that the mixtures of XG and LBG induced gel formation, and the strongest gel structure was found for the mixture of XG/LBG 3:7 according to the yield stress, storage modulus (G'), and power law parameters. Temperature ramp studies indicated that heating destroyed the gels at 55~60 °C, while cooling induced the sol-gel transition at around 52 °C for all mixtures. Structure developing rate (SDR) curves showed that XG/LBG 3:7 exhibited the highest SDR during the cooling ramp among all the samples. Non-isothermal kinetic analysis demonstrated that the gelation process of XG/LBG mixtures during cooling included two steps: a high-temperature region (55~39 °C) needing higher activation energy (Ea, 111.97 to 199.20 kJ/mol for different mixtures) and a low-temperature region (39~20 °C) needing lower Ea (74.33 to 85.31 kJ/mol), which indicated higher energy barriers to overcome at the initial stage of gel formation. The lowest Ea of 74.33 kJ/mol was found for XG/LBG 3:7 in the low-temperature region. Scanning electron microscopy (SEM) showed that the gel of XG/LBG 3:7 presented the densest entanglements. These results indicated the strongest synergism interaction occurred in XG/LBG 3:7 to form gel network structures. This study will help promote the application of XG-LBG blends to design novel food structures.

Experimental study on combined heat transfer enhancement due to macro-structured surface and electric field during electrospray cooling

Electrospray (ES) cooling is promising to achieve the high-heat-flux thermal dissipation with a low fluid consumption when using structured surfaces as heat sinks of micro-size and high-power electronics. Nevertheless, available research is still limited in the fundamental of combined heat transfer enhancement owing to the macro-structured surface and electric field. In this study, four macro-structured surfaces machined with cubic pin fins, conical pin fins, wavy fins and straight fins are compared to one flat surface under electric field to shed lights on the combined heat transfer enhancement mechanism during ethanol ES cooling. The experimental results demonstrate that both electric field and surface modification can elevate the critical heat flux (CHF) and heat transfer coefficient. A CHF of 7.93 W/cm2 is achieved by the cubic-pin-fin surface with an applied voltage of 4.5 kV at Ts = 145 °C, corresponding to a 63 % enhancement over the flat surface. The CHFs at first increase and then decline with the increased area ratio (f), and the superior heat transfer performance is achieved when f = 0.79. In the low temperature region (30 °C < Ts < 51 °C), the enhanced convection and bubble formations caused by electric field are deemed as the dominated heat transfer mechanism. The increase in nucleation sites triggered by macro-structured surfaces governs the heat transfer in the mid-temperature region (51 °C < Ts < 119 °C). Whereas, the heat transfer enhancement due to macro-structured surfaces declines in the high temperature region (Ts > 119 °C), possibly as a consequence of the large thermal resistance induced by the Leidenfrost phenomenon.

Influence of basalt fiber on performance of thin overlayer asphalt mixtures based on multiple experimental methods

Because of the fast deterioration speed of the surface function of conventional asphalt pavement, thin overlayer with many advantages has been applied to the pavement surface. However, due to problems such as insufficient stripping resistance and cracking resistance, the performance of the thin overlayer needs to be further improved. To achieve this target, basalt fiber was introduced into two types of thin overlayer asphalt mixtures (Open graded friction course, OGFC-5, and Stone matrix asphalt mixture, SMA-5). The wheel tracking test and uniaxial penetration test for high temperature deformation resistance, low temperature bending beam test and indirect tensile asphalt (IDEAL) cracking test for cracking resistance, cantabro test for stripping resistance, and friction coefficient test for skid resistance were conducted to evaluate various performance of thin overlayer asphalt mixtures, along with the dynamic modulus test for dynamic mechanical response. The results showed that adding basalt fiber could enhance the high temperature deformation resistance, low temperature cracking resistance, intermediate temperature cracking resistance and stripping resistance of the thin overlayer, while having no significant impact on skid resistance. Furthermore, adding basalt fiber could increase the modulus in the high temperature region and decrease the modulus in the low temperature region of the thin overlayer asphalt mixtures, indicating thin overlayer with basalt fiber presenting superior both high temperature and low temperature performance. In addition, the evaluation indexes of SLT and SHT proposed from dynamic modulus test exhibited good consistency with the results of the performance tests.

Inverse thermodiffusion of active matter in temperature gradient systems

We have revealed an inverse thermodiffusion phenomenon for active particles under temperature gradient in one-species systems. This counterintuitive behavior is supported by numerical calculations as well as theoretical analyses. It is presented that the active particles flow from high-temperature to low-temperature regions when the self-driving force is small. On the contrary, the active particles can flow from low-temperature to high-temperature regions as long as the self-driving force is large enough. The mass current reversal phenomenon can be explained analytically from the special swimming pressures of the active particles. The P é clet numbers defined in our work indicate a potential application in separating the particles with different activities. The findings may bring a new understanding of the physical properties of active matter and provide enlightenment for the study of the non-equilibrium collective transport of active particles.

Exploring complex magnetic phase transitions and magnetocaloric effect in the nanocrystalline Nd0.5Ca0.5MnO[formula omitted] compound

In this article, we have investigated the temperature and magnetic field-induced complex magnetic phases and magnetocaloric properties of the nanocrystalline Nd0.5Ca0.5MnO3 (NCMO) compound in detail. The compound exhibits charge-ordered antiferromagnetic (CO-AFM) and charge-orbital-ordered antiferromagnetic (AFM) phases at TCO≃ 225 K and TN= 160 K respectively. At the intermediate temperature range, i.e. TN≤ T ≤ TCO, an unfamiliar magnetic state is present where the orbital ordering of manganese ions sets progressively. Both the short-range and zig-zag ordered ferromagnetic (FM) chains and an AFM phase coexist within this temperature window. The effect of magnetic field and temperature drastically modifies the fragile magnetic ground state and this change is also reflected in the magnetocaloric properties of the studied compound. At the low-temperature region, an inverse magnetocaloric effect (MCE) is noticed due to the kinetically arrested magnetic moments of the AFM phase. However, a conventional MCE is noticed in the high-temperature regime. The anomalous behavior of the MCE in the nanocrystalline NCMO compound is analyzed by considering the effect of the reduction of particle size and the meta-stable nature of the magnetic ground state. In addition, we have paid attention to the hysteretic losses associated with the first-order phase transition (FOPT) in order to estimate the magnetic cooling capacity for the material. These studies carry notable importance for the usefulness of nanocrystalline half-doped manganite compounds not only for basic scientific research purpose, but also having possible practical utilization in the magnetic refrigeration industries.

Low-temperature electrical transport in the normal-state of overdoped cuprate superconductors

The low-temperature electrical transport in the normal-state of overdoped cuprate superconductors is investigated based on the t-J model. The momentum relaxation due to the umklapp scattering between electrons by the exchange of the effective spin propagator is employed to evaluate the electrical resistivity within the framework of the Boltzmann transport theory. It is shown that the quadratic temperature dependence of the resistivity develops in the far-lower-temperature region, and is followed by a nonlinear temperature dependence of the resistivity in an extremely-narrow-crossover region and a linear temperature dependence of the resistivity in the low-temperature region. The obtained results also show that the same spin excitation governs both superconductivity and the electron umklapp scattering responsible for the low-temperature linear in temperature resistivity in the overdoped regime.

The investigation of crystal structure, thermodynamic properties, and fluorescence properties of three new rare earth coordination compounds

Three new rare earth coordination compounds [REL3Ph]2(RE = Pr(1), Sm(2)); [ErL3Ph]2·4C2H5OH(3); (L = 2,6-dimethylbenzoate, Ph = o-phenanthroline) were synthesized. The crystal structures of the three compounds were measured by X-ray single-crystal diffraction. From the results, we made out that compounds 1–3 were binuclear structures, and 1D chain-like structures could be formed by hydrogen bonding. The thermal degradation data of the compounds and the three-dimentional infrared cumulative spectra of the gaseous decomposed products were obtained by TG/DSC-FTIR technique, and the thermal degradation patterns were explained. The isobaric molar heat capacity of compounds 1 and 2 in the low-temperature region was obtained by the DSC technique and the thermodynamic parameters were derived. The fluorescence spectrum of compound 2 was determined, showing that it had potential application value in the orange-red luminescence region.

Advancing liquid air energy storage with moving packed bed: Development and analysis from components to system level

Liquid air energy storage (LAES) technology is a promising large-scale energy storage solution due to its high capacity, scalability, and lack of geographical constraints, making it effective for integrating renewable energy sources. The core unit of the LAES system is the cold energy storage (CES) unit, which significantly influences its overall efficiency. However, the current mainstream liquid-phase and solid-phase CES methods have inherent drawbacks, including safety, environmental issues, and the dynamic effect of the thermocline. Moreover, previous research has often over-idealized the CES unit and neglected the actual heat transfer processes during the CES and cold energy release (CER) processes. In the innovative study, a gravity-driven moving packed bed (MPB) based LAES system (MPB-LAES) adopting quartz sand as the CES medium is proposed. A thermodynamic model for the LAES system is constructed, and the gas-solid counterflow coupling heat transfer model for the MPB is developed based on the continuous solid-phase model and finite difference method. The accuracy of the model is validated through experimentation using the constructed test apparatus. The research findings reveal the gas-solid coupling heat transfer characteristics in the low-temperature region of −180 °C to 30 °C, particularly the asymmetry during the CES and CER processes. The cold energy transfer mechanism within the CES unit is also uncovered, and the analysis of exergy destruction within various components is carried on. Through design parameter analysis and optimization of the MPB-LAES system, an impressive round-trip efficiency of 57.0% is achieved. This marks a significant breakthrough as it is the first report that a LAES system based on solid-phase CES has attained a round-trip efficiency (RTE) of over 55.0% while considering the actual heat transfer processes.

Temperature-related single-photon transport in a waveguide QED.

We propose a scheme to realize a novel, to the best of our knowledge, scenario that the single-photon transport in a one-dimensional waveguide can be affected by the temperature. The scheme is composed by a waveguide-atom interacting structure linked to a thermal bath. The single-photon reflection (or transmission) coefficient can be controlled by adjusting the temperature of the thermal bath. This provides a thermal control of the single-photon transport. Moreover, the scheme provides an approach for implementing the optical thermometer, in which the temperature of the thermal bath is estimated by measuring the photonic transport. The thermometer can accurately measure the temperature in the low-temperature region.

Influence of Si on the Structure and Martensitic Transformation in Deformed Ni–Mn–Ga Alloys

Abstract—The studying the effect of multiaxial isothermal forging on the microstructure and martensitic transformation in the Ni58Mn18Ga24 alloy is presented. Forging was carried out in two stages: stage 1 − forging at 700°C (4 passes, true degree of deformation e ≈ 1.64), stage 2 − forging at 500°C (1 pass, e ≈ 0.24). Forging led to the transformation of the original equiaxed grain structure. As a result of the 1st stage of processing, no new grains are formed. The new recrystallized grains are observed only after the 2nd stage of deformation, the proportion of which is very small. Apparently, the mechanism of fragmentation of the grain structure at the first stage is not triggered due to insufficient defect density at a deformation of 700°C. The characteristic temperatures of martensitic transformation are shifted to the low temperature region. The anharmonic change in the sample length is observed in the region of martensitic transformation for the both treated states. In general, this indicates a low level of defect density and internal stresses in the sample.

Effect of hydrogen addition on CO emission and thermo-chemical state near wall during head-on quenching of laminar premixed methane/air flame

A computational model for premixed methane-air flame under the flame-wall interaction was established based on CFD software and experimentally verified. The head-on quenching process of premixed methane-air flame under different hydrogen additions was simulated. The changes in CO emission, quenching distance, and the distribution of CO near the wall under different hydrogen additions were obtained. With the increase of H2 addition, the mass fraction of HCO and the generation of CO increase. Moreover, the consumption of OH in R79: OH+H2=H+H2O increases, resulting in the weakening of the oxidation of OH to CO in R94: OH+CO=CO2+H, and the EICO increases. With the increase of H2 addition, the heat release rate increases, the quenching distance decreases, and the Peclet number (Pe) increases. With the increase of hydrogen addition, the mole fraction of CO in Region A gradually decreases, the mole fraction of CO in Region B first increases and then decreases, and the mole fraction of CO in Region C increases. The temperature drops first and then rises. Near the wall (y < 0.3 mm), the convection term and diffusion term dominate, and the heat transfer time is less than the generation time and oxidation time of CO, and the generation branch and oxidation branch of CO move to the low-temperature region. Far from the wall (y ≥ 0.3 mm), the reaction source term dominates, the heat transfer time is greater than the generation time of CO, less than the oxidation time of CO, and the oxidation branch of CO moves to low temperature. With the increase of hydrogen addition, the chemical time scale of CO decreases, and the generation branches and oxidation branches of CO move to higher temperatures.

Influence of Fe3+ ion substitution on Structural, Magnetic Properties and Magnetoresistance Effect of Pr0.75Na0.05K0.20MnO3 System

The effects of partial substitution of Fe at the Mn site on structural, magnetic, and electrical properties of monovalent doped Pr0.75Na0.05K0.20Mn0.95Fe0.05O3 manganite prepared by the solid-state method were investigated. X-ray Diffractometer, AC Susceptibility, and four point probe measurements were used to characterize the structural, magnetic, and electrical properties. The sample crystallized in an orthorhombic structure with a Pnma space group. The sample exhibited ferromagnetic (FM) to paramagnetic (PM) transition behaviour with Curie Temperature, TC value of 121.5 K. From the Resistivity versus temperature analysis, the sample exhibited insulating behaviourover entire temperature from 30 K - 300 K. Fe substitution exhibited high magnetoresistance (MR %) value at low temperature region, indicating the extrinsic mechanism of MR effect.

Mechanical and Microstructural Characteristics of 1.5 GPa-Grade Boron Steel by High-Frequency Induction of Eddy Currents

In the automobile industry, high-strength plates are increasingly used to reduce vehicle weight due to strict regulations on fuel efficiency and safety, and these plates achieve a tensile strength of 1500 MPa due to the hot-stamping process. Recently, research has been conducted to examine the flow behavior of materials according to the relationship between hot stamping time-temperature characteristics, coil shape, cooling method, and thermodynamic flow characteristics of quenching materials. In this study, a basic experiment in the form of a plate was conducted using an eddy current generated during high-frequency induction heating. It presents the surface temperature change, mechanical characteristics, and microstructure of boron steel that has undergone a high-frequency induction heating process. Surface temperature data were analyzed at different high-frequency induction heating forces (15, 18, 21, 24, 27, and 30 kW) and distances from specimens (6, 9, 12, and 15 mm). Two phases, austenite and ferrite, were formed in the low-temperature region, and martensite was formed in the high-temperature region. Mechanical properties and microstructures were also analyzed under different high-frequency induction heating coil conditions. The correlation between the high-frequency induction heating force and the specimen with the maximum tensile strength was investigated. Due to high-frequency induction heating, scale generation and surface decarbonization can be avoided. As a result of this experiment, 1500 MPa of the same tensile strength as the mechanical characteristics obtained in the existing heat treatment could be obtained.

Formation of sodium-bearing species in the interstellar medium

ABSTRACT Sodium-bearing species such as NaCl in the gas phase have been observed in an assortment of carbon-rich and oxygen-rich stellar atmospheres and interstellar environments such as the high-mass protostellar disc surrounding Orion Src1 and the proto-binary system, IRAS 16547−4247. Their detection in relatively low-temperature regions is yet to be made. In this paper, we consider the synthesis of sodium-bearing species with an emphasis on NaCl, via both gas-phase and grain-surface chemistry under assorted interstellar conditions. We also consider the chemistry leading to the gas-phase species NaH and NaOH. Two classes of numerical simulations were run: models under isothermal conditions at temperatures from 10 to 800 K with varied intervals, and three-phase warm-up models that consist of an initial isothermal collapse at 10 K, followed by a warm-up phase in which temperature rises linearly to 200 K, and finally a hot core phase. We have included reactive desorption for both models to produce gaseous NaCl, NaH, and NaOH. We found that for isothermal models over a broad parameter space, the fractional abundances of gaseous NaCl and NaOH can reach above 2 × 10−10 and approx. 1 × 10−10, respectively, are in the detection range of observational facilities such as Atacama Large Millimeter/Submillimeter Array and JWST. For warm-up models, we found that if we consider molecules to be co-desorbed with water, gaseous NaCl can have a sufficiently large abundance for detection. We then conclude that both gaseous NaCl and NaOH can be detected; however, more experiments and quantum mechanical calculations are needed to constrain the relevant reaction rates better.

CO2 competes with radioactive chemicals for freshwater recovery: Hydrate-based desalination

Here, we introduce CO2 hydrate-based desalination (CHBD) technology for freshwater recovery from radioactive wastewater, for water particularly containing Cs and Sr. The hydrate equilibrium curves of CO2 hydrates shift towards lower temperature and higher pressure regions as the concentrations of CsCl and SrCl2 increase. X-ray diffraction and Raman spectroscopy measurements found that neither CsCl nor SrCl2 can affect the structure of CO2 hydrates. The high-pressure micro-differential scanning calorimetric results demonstrate that CO2 hydrates in the presence of CsCl and SrCl2 started to dissociate at lower temperatures due to the enrichment of CsCl and SrCl2 in the remaining solutions. The formation kinetics results indicate that increases in the concentrations of the radioactive chemicals lead to a decrease in the initial reaction rate and sub-cooling temperature. Solid-state nuclear magnetic resonance spectroscopy was utilized to confirm the exclusion of radioactive isotopes from solid gas hydrates. Importantly, the CHBD technology proposed in this study is applicable to radioactive wastewater containing Cs+ and Sr2+ across broad concentration ranges, spanning from a percent to hundreds of parts per million (ppm), and even sub-ppm levels, with comparable recovery efficiency. This study presents new insights into the potential of environmentally sustainable technologies to overcome the challenges posed by radioactive wastewater.

Rock damage evolution in the production process of the enhanced geothermal systems considering thermal-hydrological-mechanical and damage (THM-D)

Hot dry rocks (HDRs) geothermal relies mainly on enhanced geothermal systems (EGS) for production. During production, the evolution of rock stress distribution will cause damage to the rock, especially near fractures. The application of damage mechanics in the geothermal field has mostly focused on the process of hydraulic fracturing, with limited reports on damage research related to long-term water injection development. According to previous experimental studies, the effect of rock damage is significant and cannot be ignored. Therefore, based on a thermal-hydrological-mechanical and damage (THM-D) coupling model, it studies the rock damage evolution features and its role in changes in rock physical properties. It also analyzed the effects of the initial temperature, injection flow, fracture curvature/number, and stress difference on damage evolution. Results indicate that the damage area and degree continue to increase with time, but the growth rate becomes slower. There are two methods of damage evolution: the new damage caused by the expansion of the low-temperature region is throughout the process, and the original damage is aggravated in the later stages. Damage will cause changes such as reduced Young's modulus (negative feedback) and increased permeability (positive feedback) of the rock matrix, which in turn affect the damage evolution. More, damage increases with the initial rock temperature, injection mass flow, and stress difference increase, and the impact of the fracture curvature is small. The damage of complex fracture reservoirs is more pronounced than that of single fracture reservoirs. This study provides a tool for analyzing the impact of damage on the production performance of HDRs. The investigation of relevant patterns is expected to offer guidance for production strategies.

Phonon share to the thermal capacitance of ultrathin crystalline film along the entire temperature region

As a result of theoretical considerations on the study of the influence of the phonon quasiparticle subsystem on the thermal capacitance of a two-dimensional quasicrystal in the form of an ultrathin film, an exact formula for the thermal capacitance of an ideal ultrathin film, valid over the entire temperature range, is derived in this paper. The dispersion equation as well as the possible phonon energies and allowed phonon states were determined by the method of Green’s functions. The obtained formula for the thermal capacitance of the ultrathin film is plotted and compared with the corresponding graphs representing massive crystalline structures in both the low-temperature and high-temperature regions. The conclusions that can be drawn are highly consistent with recent results related to the possibility of realizing high-temperature superconductivity.