Thermodynamic Properties of the First-Generation Hybrid Dendrimer with “Carbosilane Core/Phenylene Shell” Structure

The molar heat capacity of the first-generation hybrid dendrimer with a “carbosilane core/phenylene shell” structure was measured for the first time in the temperature range T = 6–600 K using a precise adiabatic vacuum calorimeter and DSC. In the above temperature interval, the glass transition of the studied compound was observed, and its thermodynamic characteristics were determined. The standard thermodynamic functions (the enthalpy, the entropy, and the Gibbs energy) of the hybrid dendrimer were calculated over the range from T = 0 to 600 K using the experimentally determined heat capacity. The standard entropy of formation of the investigated dendrimer was evaluated at T = 298.15 K. The obtained thermodynamic properties of the studied hybrid dendrimer were compared and discussed with the literature data for some of the first-generation organosilicon and pyridylphenylene dendrimers.

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Calorimetric Study of Iodine Pentafluoride: Heat Capacity between 5 and 350°K, Enthalpy of Fusion and Vaporization, Standard Entropy of the Vapor, and Other Thermodynamic Properties

The Journal of Chemical Physics ◽

10.1063/1.1675430 ◽

1971 ◽

Vol 54 (9) ◽

pp. 3790-3798 ◽

Cited By ~ 16

Author(s):

Darrell W. Osborne ◽

Felix Schreiner ◽

Henry Selig

Keyword(s):

Heat Capacity ◽

Thermodynamic Properties ◽

Enthalpy Of Fusion ◽

Calorimetric Study ◽

Standard Entropy

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Thermodynamic study of a synthetic analog of the famatinite mineral - Cu3SbS4

Фізика і хімія твердого тіла ◽

10.15330/pcss.22.1.53-58 ◽

2021 ◽

Vol 22 (1) ◽

pp. 53-58

Author(s):

P.R. Mammadli ◽

L.F. Mashadiyeva ◽

Z.T. Hasanova ◽

D.M. Babanly

Keyword(s):

Thermodynamic Functions ◽

Measurement Data ◽

Phase Region ◽

S Phase ◽

Synthetic Analog ◽

Standard Entropy ◽

Emf Measurements ◽

Standard Thermodynamic Functions ◽

First Time ◽

Thermodynamic Functions Of Formation

Fundamental thermodynamic properties of the synthetic analog of the famatinite mineral - Cu3SbS4 were studied on the basis of electromotive force (EMF) measurements. The EMF of the concentration chains relative to the Cu electrode with a solid electrolyte was measured for the alloys from the Cu3SbS4 + Sb2S3 + S phase region at 300-380K temperature interval. Based on measurement data, the relative partial thermodynamic functions of copper in alloys, the standard thermodynamic functions of formation, as well as, the standard entropy of the Cu3SbS4 ternary compound were calculated for the first time.

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Thermodynamıc Propertıes of the BiTe and Bi8Te9 Compounds

Фізика і хімія твердого тіла ◽

10.15330/pcss.21.4.714-719 ◽

2020 ◽

Vol 21 (4) ◽

pp. 714-719

Author(s):

G.S. Hasanova ◽

A.I. Aghazade ◽

Y.A. Yusibov ◽

M.B. Babanly

Keyword(s):

Comparative Analysis ◽

Thermodynamic Properties ◽

Thermodynamic Functions ◽

Partial Functions ◽

Two Phase ◽

Standard Thermodynamic Functions ◽

Temperature Range ◽

First Time ◽

Thermodynamic Functions Of Formation

Two-phase alloys Bi8Te9+Bi4Te5 and BiTe+Bi8Te9 were studied by the electromotive forces method (EMF) in the temperature range 300-450 K. From the EMF data, the relative partial molar functions of bismuth in the alloys were calculated. The potential-forming reactions responsible for these partial functions were compiled, the values of the standard thermodynamic functions of formation, and the standard entropies of Bi8Te9 and BiTe compounds were calculated. A comparative analysis of the data for BiTe with the literature data was carried out; for Bi8Te9, the thermodynamic functions were obtained for the first time.

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Thermodynamic properties of the GdTe3 compound

Фізика і хімія твердого тіла ◽

10.15330/pcss.22.3.420-425 ◽

2021 ◽

Vol 22 (3) ◽

pp. 420-425

Author(s):

Samira Imamaliyeva

Keyword(s):

Thermodynamic Properties ◽

Thermodynamic Functions ◽

Standard Entropy ◽

X Ray Diffraction ◽

Emf Measurements ◽

Standard Thermodynamic Functions ◽

X Ray ◽

Temperature Range ◽

Concentration Cells ◽

Thermodynamic Functions Of Formation

The alloys of the Gd-Te system in the range of compositions > 75 at% Te were studied by the methods of X-ray diffraction (XRD) and electromotive forces (EMF). From the EMF measurements of the concentration cells relative to the GdTe electrode in the 300-450 K temperature range, the partial thermodynamic functions of GdTe in alloys were determined. By combining these data with the corresponding functions of Gd in GdTe, the partial molar functions of gadolinium in GdTe3+Te alloys, and standard thermodynamic functions of formation and standard entropy of the GdTe3 compound were calculated. The obtained results were compared with the literature data.

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ABOUT HEAT CAPACITY OF TITANIUM CARBIDE TiCx

Alternative Energy and Ecology (ISJAEE) ◽

10.15518/isjaee.2019.01-03.056-066 ◽

2019 ◽

pp. 56-66

Author(s):

I. Khidirov ◽

V. V. Getmanskiy ◽

A. S. Parpiev ◽

Sh. A. Makhmudov

Keyword(s):

Heat Capacity ◽

High Temperature ◽

Titanium Carbide ◽

Temperature Dependence ◽

Carbon Concentration ◽

Room Temperature ◽

Thermodynamic Characteristics ◽

Liquid Nitrogen Temperature ◽

Analysis Data ◽

Thermal Excitation

This work relates to the field of thermophysical parameters of refractory interstitial alloys. The isochoric heat capacity of cubic titanium carbide TiCx has been calculated within the Debye approximation in the carbon concentration range x = 0.70–0.97 at room temperature (300 K) and at liquid nitrogen temperature (80 K) through the Debye temperature established on the basis of neutron diffraction analysis data. It has been found out that at room temperature with decrease of carbon concentration the heat capacity significantly increases from 29.40 J/mol·K to 34.20 J/mol·K, and at T = 80 K – from 3.08 J/mol·K to 8.20 J/mol·K. The work analyzes the literature data and gives the results of the evaluation of the high-temperature dependence of the heat capacity СV of the cubic titanium carbide TiC0.97 based on the data of neutron structural analysis. It has been proposed to amend in the Neumann–Kopp formula to describe the high-temperature dependence of the titanium carbide heat capacity. After the amendment, the Neumann–Kopp formula describes the results of well-known experiments on the high-temperature dependence of the heat capacity of the titanium carbide TiCx. The proposed formula takes into account the degree of thermal excitation (a quantized number) that increases in steps with increasing temperature.The results allow us to predict the thermodynamic characteristics of titanium carbide in the temperature range of 300–3000 K and can be useful for materials scientists.

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Multicanonical Molecular Dynamics Simulation Study of the Liquid-Solid and Solid-Solid Transitions in Lennard-Jones Clusters

ASME/JSME 2011 8th Thermal Engineering Joint Conference ◽

10.1115/ajtec2011-44457 ◽

2011 ◽

Author(s):

Toshihiro Kaneko ◽

Kenji Yasuoka ◽

Ayori Mitsutake ◽

Xiao Cheng Zeng

Keyword(s):

Molecular Dynamics ◽

Heat Capacity ◽

Transition Temperature ◽

Peak Position ◽

Temperature Curve ◽

Dynamics Simulation ◽

Lennard Jones ◽

Dynamics Simulations ◽

First Time ◽

Good Agreement

Multicanonical molecular dynamics simulations are applied, for the first time, to study the liquid-solid and solid-solid transitions in Lennard-Jones (LJ) clusters. The transition temperatures are estimated based on the peak position in the heat capacity versus temperature curve. For LJ31, LJ58 and LJ98, our results on the solid-solid transition temperature are in good agreement with previous ones. For LJ309, the predicted liquid-solid transition temperature is also in agreement with previous result.

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Temperature Dependence of Thermophysical Properties of Full-Scale Corium of Fast Energy Reactor

Science and Technology of Nuclear Installations ◽

10.1155/2017/8294653 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7

Author(s):

Mazhyn K. Skakov ◽

Nurzhan Ye. Mukhamedov ◽

Alexander D. Vurim ◽

Ilya I. Deryavko

Keyword(s):

Heat Capacity ◽

Thermal Diffusivity ◽

Fast Reactor ◽

Thermophysical Properties ◽

Heat Conductivity ◽

Nuclear Reactor ◽

Reactor Vessel ◽

Full Scale ◽

Temperature Fields ◽

First Time

For the first time the paper determines thermophysical properties (specific heat capacity, thermal diffusivity, and heat conductivity) of the full-scale corium of the fast energy nuclear reactor within the temperature range from ~30°С to ~400°С. Obtained data are to be used in temperature fields calculations during modeling the processes of corium melt retention inside of the fast reactor vessel.

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