The normal spectral emissivity at 807 and 940 nm and heat capacity at constant pressure of Pd–Fe melts were measured under electromagnetic levitation with a static magnetic field. The samples were made of Fe of mass purity 99.9985%. The present emissivity of Fe melts was relatively low compared with previously reported data using Fe with purity lower than 99.95% mass purity. The spectral emission of the Fe melts was analyzed using their normal spectral emissivity obtained from the Drude model. The excess heat capacity of Pd–Fe melts was evaluated from the measured heat capacity of Pd–Fe melts. Applying the Lupis–Elliot rule, we concluded from the obtained excess heat capacity that the enthalpy of mixing and excess entropy of the Pd–Fe melts should be negative. The composition dependence of the enthalpy of mixing, excess entropy, and excess Gibbs energy of Pd–Fe melts were evaluated using data obtained in this study and the literature.
{"title":"Normal spectral emissivity and heat capacity of Pd–Fe melts measured at constant pressure under electromagnetic levitation with a static magnetic field","authors":"M. Watanabe, M. Adachi, M. Uchikoshi, H. Fukuyama","doi":"10.32908/hthp.v52.1423","DOIUrl":"https://doi.org/10.32908/hthp.v52.1423","url":null,"abstract":"The normal spectral emissivity at 807 and 940 nm and heat capacity at constant pressure of Pd–Fe melts were measured under electromagnetic levitation with a static magnetic field. The samples were made of Fe of mass purity 99.9985%. The present emissivity of Fe melts was relatively low compared with previously reported data using Fe with purity lower than 99.95% mass purity. The spectral emission of the Fe melts was analyzed using their normal spectral emissivity obtained from the Drude model. The excess heat capacity of Pd–Fe melts was evaluated from the measured heat capacity of Pd–Fe melts. Applying the Lupis–Elliot rule, we concluded from the obtained excess heat capacity that the enthalpy of mixing and excess entropy of the Pd–Fe melts should be negative. The composition dependence of the enthalpy of mixing, excess entropy, and excess Gibbs energy of Pd–Fe melts were evaluated using data obtained in this study and the literature.","PeriodicalId":12983,"journal":{"name":"High Temperatures-high Pressures","volume":"44 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69443349","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}
O. Takeda, Noritaka Ouchi, Kounosuke Takagi, Y. Sato, Hogmin Zhu
The viscosities of the molten Cu–Ni and Cu–Al alloys were measured using an oscillating crucible method over the entire composition range to obtain reliable data and examine composition dependence precisely. The measured viscosities of all alloys showed good consistency in heating and cooling processes, and the logarithmic viscosities showed good Arrhenius-type linearity, indicating that no considerable change in the liquid structure occurs in the temperature range studied. The composition dependence of the viscosity of Cu–Ni alloys was close to that defined by the additive law of logarithmic viscosities of pure components, whereas the composition dependence of the viscosity of Cu–Al alloys was far from that defined by the additive law, where the logarithmic viscosity increased with the addition of a small amount of Al and showed a peak. Over the peak concentration, the logarithmic viscosity monotonically decreased with further addition of Al. Deviations from the additive law of logarithmic viscosity of molten Cu–Al alloys at 1773 K were maximum at low Al concentrations; in contrast, the excess molar volumes of Cu–Al alloys showed minimum at low Al concentrations. The increase in viscosity in the low-Al-concentration region of the Cu–Al alloy is attributed to the decrease in the interatomic distance, which reduces the freedom of movement of atoms.
{"title":"Viscosity of molten Cu–M alloys (M = Ni, Al)","authors":"O. Takeda, Noritaka Ouchi, Kounosuke Takagi, Y. Sato, Hogmin Zhu","doi":"10.32908/hthp.v52.1365","DOIUrl":"https://doi.org/10.32908/hthp.v52.1365","url":null,"abstract":"The viscosities of the molten Cu–Ni and Cu–Al alloys were measured using an oscillating crucible method over the entire composition range to obtain reliable data and examine composition dependence precisely. The measured viscosities of all alloys showed good consistency in heating and cooling processes, and the logarithmic viscosities showed good Arrhenius-type linearity, indicating that no considerable change in the liquid structure occurs in the temperature range studied. The composition dependence of the viscosity of Cu–Ni alloys was close to that defined by the additive law of logarithmic viscosities of pure components, whereas the composition dependence of the viscosity of Cu–Al alloys was far from that defined by the additive law, where the logarithmic viscosity increased with the addition of a small amount of Al and showed a peak. Over the peak concentration, the logarithmic viscosity monotonically decreased with further addition of Al. Deviations from the additive law of logarithmic viscosity of molten Cu–Al alloys at 1773 K were maximum at low Al concentrations; in contrast, the excess molar volumes of Cu–Al alloys showed minimum at low Al concentrations. The increase in viscosity in the low-Al-concentration region of the Cu–Al alloy is attributed to the decrease in the interatomic distance, which reduces the freedom of movement of atoms.","PeriodicalId":12983,"journal":{"name":"High Temperatures-high Pressures","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69443190","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}
Toshiki Kondo, T. Toda, J. Takeuchi, S. Kikuchi, F. Kargl, H. Muta, Y. Ohishi
In order to establish an evaluation method/numerical simulation for nuclear reactor safety under severe accidental conditions, it is necessary to obtain the physical properties of the relevant molten materials at very high temperatures. In particular, the reaction/interaction between the melt of stainless-steel oxide originating from the nuclear reactor component and the composition of structural concrete is an important phenomenon in terms of understanding of the progress of severe accidents in nuclear power plants and the planning/installation of equipment/devices as countermeasures. The installation of a core catcher is one possible countermeasure to safely terminate a severe accident. For this to work a sacrificial material is placed in the core catcher to increase the fluidity of the molten material. Iron oxide (Fe2O3) is considered a promising candidate. In this study, thermophysical properties such as the density and the viscosity of a (Fe2O3)0.95-(SiO2)0.05 mixture were obtained using the aerodynamic levitation method. The chosen composition is representative for the Molten-Core-Concrete-Interaction at early stages of a severe accident event. Although partial Fe2O3 changes to Fe3O4 during the experiment, this composition change would occur under the actual severe accident conditions. The physical property values of the (Fe2O3)0.95-(SiO2)0.05 mixture were almost the same as those of Fe2O3 obtained in an earlier study. Therefore, it can be concluded that the fluidity of Fe2O3 is not significantly affected in the early stages of a severe accident whereby small amounts of SiO2 (approximately 5 mol. %) are dissolved into Fe2O3.
{"title":"Thermophysical properties of molten (Fe2O3)0.95-(SiO2)0.05 measured by aerodynamic levitation","authors":"Toshiki Kondo, T. Toda, J. Takeuchi, S. Kikuchi, F. Kargl, H. Muta, Y. Ohishi","doi":"10.32908/hthp.v52.1405","DOIUrl":"https://doi.org/10.32908/hthp.v52.1405","url":null,"abstract":"In order to establish an evaluation method/numerical simulation for nuclear reactor safety under severe accidental conditions, it is necessary to obtain the physical properties of the relevant molten materials at very high temperatures. In particular, the reaction/interaction between the melt of stainless-steel oxide originating from the nuclear reactor component and the composition of structural concrete is an important phenomenon in terms of understanding of the progress of severe accidents in nuclear power plants and the planning/installation of equipment/devices as countermeasures. The installation of a core catcher is one possible countermeasure to safely terminate a severe accident. For this to work a sacrificial material is placed in the core catcher to increase the fluidity of the molten material. Iron oxide (Fe2O3) is considered a promising candidate. In this study, thermophysical properties such as the density and the viscosity of a (Fe2O3)0.95-(SiO2)0.05 mixture were obtained using the aerodynamic levitation method. The chosen composition is representative for the Molten-Core-Concrete-Interaction at early stages of a severe accident event. Although partial Fe2O3 changes to Fe3O4 during the experiment, this composition change would occur under the actual severe accident conditions. The physical property values of the (Fe2O3)0.95-(SiO2)0.05 mixture were almost the same as those of Fe2O3 obtained in an earlier study. Therefore, it can be concluded that the fluidity of Fe2O3 is not significantly affected in the early stages of a severe accident whereby small amounts of SiO2 (approximately 5 mol. %) are dissolved into Fe2O3.","PeriodicalId":12983,"journal":{"name":"High Temperatures-high Pressures","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69443234","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}
Yuto Suganuma, Saori Shinohara, Y. Inoue, T. Nishi, H. Ohta, Hiroshi Tanei, M. Susa, R. Endo
Fayalite (Fe2SiO4) is a major component of olivine and is often formed in the surface oxide layer (oxide scale) on steel plates owing to its high-temperature oxidation. The thermal conductivity of the oxide scale and its constituents, including fayalite, is essential for controlling the cooling rate of hot steel plates. Therefore, this study uses modulated thermoreflectance microscopy to determine the thermal effusivity/conductivity of fayalite particles with diameters smaller than 180 μm because the sample commercially available is such a small size. This thermal optical microscopy enables the measurement of thermal effusivity for small areas, such as 10 μm. The thermal effusivity and conductivity were found to be 4.1 ± 0.2 kJs-0.5K-1m-2 and 6.0 ± 0.5 Wm-1K-1, respectively. These values are representative of the bulk value. Additionally, the thermal conductivity of fayalite is shown to be higher than that of wüstite (Fe1-xO), which is the main component of the oxide scale. The oxide scale formed on the thick steel plate comprises a Si-rich layer, a wüstite layer, and a magnetite layer. Furthermore, the Si-rich layer comprises fayalite, wüstite, and pores. The effective thermal conductivity of the Si-rich layer was calculated by observing the oxide scale formed on the steel plate. The low thermal conductivity of the Si-rich layer indicates that the thermal conductivity of the layer is strongly affected by the porosity of the oxide scale. Furthermore, although the Si-rich layer is thin, it significantly contributes to the heat resistance of the oxide scale.
铁矾石(Fe2SiO4)是橄榄石的主要成分，由于其高温氧化作用，常在钢板表面氧化层(氧化垢)中形成。氧化垢及其成分(包括铁矾)的导热性对于控制热钢板的冷却速度至关重要。因此，本研究使用调制热反射显微镜来确定直径小于180 μm的铁矾石颗粒的热渗透率/电导率，因为市售样品尺寸很小。该热光学显微镜可以测量小区域(如10 μm)的热渗透率。热溢率和导热系数分别为4.1±0.2 kks -0.5 k -1m-2和6.0±0.5 wm -1m- 1。这些值代表了批量值。此外，铁矾石的导热系数高于钨钛石(Fe1-xO)，后者是氧化垢的主要成分。在厚钢板上形成的氧化层包括富硅层、钨钛矿层和磁铁矿层。富硅层主要由铁矾石、钨晶石和孔隙组成。通过观察富硅层在钢板上形成的氧化皮，计算了富硅层的有效导热系数。富硅层的低导热系数表明，富硅层的导热系数受氧化层孔隙率的影响较大。此外，虽然富硅层很薄，但它对氧化垢的耐热性有显著的贡献。
{"title":"Quantitative thermal investigation of a fayalite particle and a Si-rich layer in oxide scale formed on steel","authors":"Yuto Suganuma, Saori Shinohara, Y. Inoue, T. Nishi, H. Ohta, Hiroshi Tanei, M. Susa, R. Endo","doi":"10.32908/hthp.v52.1409","DOIUrl":"https://doi.org/10.32908/hthp.v52.1409","url":null,"abstract":"Fayalite (Fe2SiO4) is a major component of olivine and is often formed in the surface oxide layer (oxide scale) on steel plates owing to its high-temperature oxidation. The thermal conductivity of the oxide scale and its constituents, including fayalite, is essential for controlling the cooling rate of hot steel plates. Therefore, this study uses modulated thermoreflectance microscopy to determine the thermal effusivity/conductivity of fayalite particles with diameters smaller than 180 μm because the sample commercially available is such a small size. This thermal optical microscopy enables the measurement of thermal effusivity for small areas, such as 10 μm. The thermal effusivity and conductivity were found to be 4.1 ± 0.2 kJs-0.5K-1m-2 and 6.0 ± 0.5 Wm-1K-1, respectively. These values are representative of the bulk value. Additionally, the thermal conductivity of fayalite is shown to be higher than that of wüstite (Fe1-xO), which is the main component of the oxide scale. The oxide scale formed on the thick steel plate comprises a Si-rich layer, a wüstite layer, and a magnetite layer. Furthermore, the Si-rich layer comprises fayalite, wüstite, and pores. The effective thermal conductivity of the Si-rich layer was calculated by observing the oxide scale formed on the steel plate. The low thermal conductivity of the Si-rich layer indicates that the thermal conductivity of the layer is strongly affected by the porosity of the oxide scale. Furthermore, although the Si-rich layer is thin, it significantly contributes to the heat resistance of the oxide scale.","PeriodicalId":12983,"journal":{"name":"High Temperatures-high Pressures","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69443252","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}
H. Kobatake, Masaya Iwabuchi, Yuma Kurokawa, M. Ohtsuka, M. Adachi, H. Fukuyama, N. Sasajima, Yoshiro Yamada
The applicability of the dual-wavelength reflectance-ratio (DWR) method to emissivity-free radiation thermometry of electromagnetically levitated high-temperature liquid metals was investigated. To establish the measurement technique, the DWR method was applied to liquid Ni levitated in a static magnetic field, which suppresses the surface oscillation and the translational motion. In a previous study, temperature of the levitated liquid metals measured by DWR showed deviations of about 95 K to 175 K from the temperature measured by a calibrated pyrometer. Since this discrepancy could be attributed to the imperfect contribution of the auxiliary light, the effect of the optical setup of the auxiliary light on the temperature measurement was investigated in this study. By using a reflecting collimator for the auxiliary optical system and adopting the radiance ratio determined considering the geometrical arrangement of the measurement system, the difference between temperature of liquid Ni kept near its melting temperature (𝑇𝑚 = 1728 K) measured using DWR and the temperature measured by a pyrometer calibrated using the melting point of Ni was 12 K on average and the standard deviation in the temperature measurement was 25 K (𝑛 = 5).
{"title":"Dual-wavelength reflectance-ratio method for emissivity-free temperature measurements applied to electromagnetically levitated liquid Ni","authors":"H. Kobatake, Masaya Iwabuchi, Yuma Kurokawa, M. Ohtsuka, M. Adachi, H. Fukuyama, N. Sasajima, Yoshiro Yamada","doi":"10.32908/hthp.v52.1431","DOIUrl":"https://doi.org/10.32908/hthp.v52.1431","url":null,"abstract":"The applicability of the dual-wavelength reflectance-ratio (DWR) method to emissivity-free radiation thermometry of electromagnetically levitated high-temperature liquid metals was investigated. To establish the measurement technique, the DWR method was applied to liquid Ni levitated in a static magnetic field, which suppresses the surface oscillation and the translational motion. In a previous study, temperature of the levitated liquid metals measured by DWR showed deviations of about 95 K to 175 K from the temperature measured by a calibrated pyrometer. Since this discrepancy could be attributed to the imperfect contribution of the auxiliary light, the effect of the optical setup of the auxiliary light on the temperature measurement was investigated in this study. By using a reflecting collimator for the auxiliary optical system and adopting the radiance ratio determined considering the geometrical arrangement of the measurement system, the difference between temperature of liquid Ni kept near its melting temperature (𝑇𝑚 = 1728 K) measured using DWR and the temperature measured by a pyrometer calibrated using the melting point of Ni was 12 K on average and the standard deviation in the temperature measurement was 25 K (𝑛 = 5).","PeriodicalId":12983,"journal":{"name":"High Temperatures-high Pressures","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69443691","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}
Lili Liu, Cai Chen, Linlin Shen, Gang Xu, Y. Wen, Xianshi Zeng
The pressure dependence of the lattice and elastic constants of the binary precipitates γ-TiAl, DO22-Al3Ti and α2-Ti3Al are firstly investigated by using a first-principles approach. The calculated results at 0 GPa and 0 K agree well with the existing experimental and other theoretical values. Using the density-functional perturbation theory (DFPT) under the quasiharmonic approximation (QHA), the temperature and pressure dependencies of the bulk modulus, the Gibbs free energy, the thermal expansion coefficient, as well as the heat capacity at constant pressure are investigated systematically in the ranges of 0–1000 K and 0–30 GPa.
{"title":"Structural, elastic and thermodynamic properties of the binary precipitates γ-TiAl, DO22-Al3Ti and α2-Ti3Al","authors":"Lili Liu, Cai Chen, Linlin Shen, Gang Xu, Y. Wen, Xianshi Zeng","doi":"10.32908/hthp.v52.1133","DOIUrl":"https://doi.org/10.32908/hthp.v52.1133","url":null,"abstract":"The pressure dependence of the lattice and elastic constants of the binary precipitates γ-TiAl, DO22-Al3Ti and α2-Ti3Al are firstly investigated by using a first-principles approach. The calculated results at 0 GPa and 0 K agree well with the existing experimental and other theoretical values. Using the density-functional perturbation theory (DFPT) under the quasiharmonic approximation (QHA), the temperature and pressure dependencies of the bulk modulus, the Gibbs free energy, the thermal expansion coefficient, as well as the heat capacity at constant pressure are investigated systematically in the ranges of 0–1000 K and 0–30 GPa.","PeriodicalId":12983,"journal":{"name":"High Temperatures-high Pressures","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69443206","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}
The strain and magnetic field effect on thermodynamic properties of a two dimensional GaAs quantum dot (QD) is investigated within the effective mass approximation. To this end, first we have obtained the wave functions and energy levels of the system in the presence of Bychkov-Rashba and Dressalhaus terms. Then using the obtained energy levels, we have computed the partition function by the Poisson summation formalism. Afterward, we have deduced some thermodynamic properties such as mean energy, entropy, specific heat and free energy using the canonical ensemble approach. Finally, the thermodynamic properties for a two dimensional GaAs QD have been discussed in detail.
{"title":"Strain and magnetic field effect on thermodynamic properties of a two dimensional GaAs quantum dot","authors":"Ahmad Ghanbari","doi":"10.32908/hthp.v52.1391","DOIUrl":"https://doi.org/10.32908/hthp.v52.1391","url":null,"abstract":"The strain and magnetic field effect on thermodynamic properties of a two dimensional GaAs quantum dot (QD) is investigated within the effective mass approximation. To this end, first we have obtained the wave functions and energy levels of the system in the presence of Bychkov-Rashba and Dressalhaus terms. Then using the obtained energy levels, we have computed the partition function by the Poisson summation formalism. Afterward, we have deduced some thermodynamic properties such as mean energy, entropy, specific heat and free energy using the canonical ensemble approach. Finally, the thermodynamic properties for a two dimensional GaAs QD have been discussed in detail.","PeriodicalId":12983,"journal":{"name":"High Temperatures-high Pressures","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135712618","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}
In the present study, a phenomenological model based on thermodynamic variables is developed to study the thermophysical properties of nanomaterials with respect to size in nanoscale. The model input parameters are lattice packing fraction depending on crystal structure and atomic diameter of nanosolid. The shape parameter is incorporated in the model to study the variation in physical properties of metallic nanosolids with shape. The size and shape effect on melting temperature 𝑇𝑀𝑁, Debye temperature θ𝐷𝑁, Specific heat capacity 𝐶𝑁, thermal conductivity 𝐾𝑁 and electrical conductivity σ𝑁 is studied in metallic nanosolids. It is observed from the results obtained that both melting temperature and Debye temperature get reduced with reduction in size of nanosolid. Also Thermal conductivity and electrical conductivity in nanosolids decrease as size reduces. This is due to the increase in the number of surface atoms with size reduction and pronounced quantum confinement in nanomaterials. Also, the drastic change in number of surface atoms with the change in shape of the nanomaterial of same size brings about change in its thermophysical properties. The present model results are found consistent with the available experimental and simulated results of previous workers and may be useful for experimental researchers exploring the physical properties of nanomaterials.
{"title":"Study of size effect on thermophysical properties of metallic nanosolids","authors":"M. Goyal","doi":"10.32908/hthp.v52.1305","DOIUrl":"https://doi.org/10.32908/hthp.v52.1305","url":null,"abstract":"In the present study, a phenomenological model based on thermodynamic variables is developed to study the thermophysical properties of nanomaterials with respect to size in nanoscale. The model input parameters are lattice packing fraction depending on crystal structure and atomic diameter of nanosolid. The shape parameter is incorporated in the model to study the variation in physical properties of metallic nanosolids with shape. The size and shape effect on melting temperature 𝑇𝑀𝑁, Debye temperature θ𝐷𝑁, Specific heat capacity 𝐶𝑁, thermal conductivity 𝐾𝑁 and electrical conductivity σ𝑁 is studied in metallic nanosolids. It is observed from the results obtained that both melting temperature and Debye temperature get reduced with reduction in size of nanosolid. Also Thermal conductivity and electrical conductivity in nanosolids decrease as size reduces. This is due to the increase in the number of surface atoms with size reduction and pronounced quantum confinement in nanomaterials. Also, the drastic change in number of surface atoms with the change in shape of the nanomaterial of same size brings about change in its thermophysical properties. The present model results are found consistent with the available experimental and simulated results of previous workers and may be useful for experimental researchers exploring the physical properties of nanomaterials.","PeriodicalId":12983,"journal":{"name":"High Temperatures-high Pressures","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69443306","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}
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