Thermodynamic Functions of Terbium Hafnate

The molar heat capacity of terbium hafnate with a pyrochlore structure was measured by relaxation and adiabatic calorimetry. The smoothed values of the molar heat capacity were used to calculate the thermodynamic functions in the temperature range 6–330 K. The general form of the Schottky anomaly was determined.

TEMPERATURE DEPENDENCE OF HEAT CAPACITY SCANDIUM, YTTRIUM, CERIUM, PRASEODYMIUM, NEODYMIUM AND EUROPIUM

Using the Sigma Plot program, using the available experimental data on the heat capacity of scandium, yttrium, praseodymium, cerium, neodymium, lanthanum, and europium, the equations of the temperature dependence of the specific and molar heat capacity were established. The optimal degrees for the temperature in these equations were determined using the Fisher statistical criterion. It is revealed that the general form of the temperature dependence of the heat capacity for these metals is a four-term polynomial in the form C (T) = a + b T + c T2 + d T3.

On the Determination of Molar Heat Capacity of Transition Elements: From the Absolute Zero to the Melting Point

Molar specific heat is one of the most important thermophysical properties to determine the sensible heat, heat of transformation, enthalpy, entropy, thermal conductivity, and many other physical properties present in several fields of physics, chemistry, materials science, metallurgy, and engineering. Recently, a model was proposed to calculate the Density of State by limiting the total number of modes by solid–liquid and solid–solid phase nucleation and by the entropy associated with phase transition. In this model, the new formulation of Debye’s equation encompasses the phonic, electronic, and rotational energies contributions to the molar heat capacity of the solids. Anomalies observed in the molar specific heat capacity, such as thermal, magnetic, configurational transitions, and electronic, can be treated by their transitional entropies. Model predictions are compared with experimental scatter for transitional elements.

Generality of Correlation between Yield and Reduced Mass of Raw Materials in Organic Reactions

To validate a generality of the correlation between product yield and reduced mass of raw materials, the regression analysis of 129 reaction examples (55 as a sample size) including at least 66 types of reactions used in syntheses of natural products such as peptides and terpenes was conducted. It was possible to predict a yield of a variety of synthetic reactions for a synthesis of natural product with many aliphatic carbon chains by applying a reduced mass, adjusted with a molecular weight and the number of rotatable bond, to the regression equation. Moreover, it was found that the increase in yield due to a use of the adjusted reduced mass correlated with the harmonic mean of the molar heat capacity of raw materials and was expressed as a second-order approximation within the analysis range.<br>

Generality of Correlation between Yield and Reduced Mass of Raw Materials in Organic Reactions

To validate a generality of the correlation between product yield and reduced mass of raw materials, the regression analysis of 129 reaction examples (55 as a sample size) including at least 66 types of reactions used in syntheses of natural products such as peptides and terpenes was conducted. It was possible to predict a yield of a variety of synthetic reactions for a synthesis of natural product with many aliphatic carbon chains by applying a reduced mass, adjusted with a molecular weight and the number of rotatable bond, to the regression equation. Moreover, it was found that the increase in yield due to a use of the adjusted reduced mass correlated with the harmonic mean of the molar heat capacity of raw materials and was expressed as a second-order approximation within the analysis range.<br>

Теплоемкость скандобората NdSc-=SUB=-3-=/SUB=-(BO_3)-=SUB=-4-=/SUB=-

Single crystals of trigonal neodymium scandoborate NdSc3(BO3)4 were grown by the group method from a solution-melt based on bismuth trimolybdate. The molar heat capacity C(T) was studied in the temperature range 2-300 K and magnetic fields up to 9 T. The experimental curve was approximated by the combined Debye-Einstein model. The lattice contribution was determined from ab-initio calculations. Schottky anomaly was observed in the low-temperature region C(T) with the applied magnetic field.

Electronic heat capacity of some vanadium compounds at low temperatures

The paper presents the results of a study of the temperature dependence of molar heat capacity at constant pressure in the range (from 5 to 300 K) for vanadium-based materials. For all the studied materials, the values of the density of States near the Fermi level are calculated. It was found that for V3Si and V3Ge materials, the values of the state density μ( E ) correlate with the transition temperatures to the superconducting state. For materials V2O3 and V1.973Me0.027O3 (Me - Al, Fe, Cr), it was found that the temperatures of metal-dielectric phase transitions decrease with increasing values of the density of States.