Phase Transitions in the Alkali C1 —n. C4 Alkanoates

1975 ◽  
Vol 30 (11) ◽  
pp. 1447-1457 ◽  
Author(s):  
P. Ferloni ◽  
M. Sanesi ◽  
P. Franzosini
Keyword(s):  
Differential Scanning Calorimetry ◽  
Heat Capacity ◽  
Phase Transitions ◽  
Solid State ◽  
Thermal Behaviour ◽  
Heat Capacity Data ◽  
Supplementary Information ◽  
State Transitions ◽  
Scanning Calorimetry ◽  
Capacity Data

The enthalpies and entropies of fusion and of solid state transitions in Li formate and acetate; Li, Na, K, Rb, Cs propionates; Li, Rb, Cs n.butyrates were determined by differential scanning calorimetry. Supplementary information was provided through conductance measurements on solids. The collected data, together with those from previous papers, allowed to give a picture of the thermal behaviour of the alkali C1-n. C4 alkanoates.Heat capacity data on solid and molten Na formate, acetate and propionate were also determined

scholarly journals Identification of Phase Fraction–Temperature Curves from Heat Capacity Data for Numerical Modeling of Heat Transfer in Commercial Paraffin Waxes

Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5149 ◽  
Author(s):  
Tilman Barz ◽  
Johannes Krämer ◽  
Johann Emhofer
Keyword(s):  
Heat Transfer ◽  
Heat Capacity ◽  
Numerical Solutions ◽  
Spline Approximation ◽  
Heat Capacity Data ◽  
Phase Fraction ◽  
Supplementary Information ◽  
Scanning Calorimetry ◽  
Apparent Heat Capacity ◽  
Capacity Data

The area-proportional baseline method generates phase fraction–temperature curves from heat capacity data of phase change materials. The curves describe the continuous conversion from solid to liquid over an extended temperature range. They are consistent with the apparent heat capacity and enthalpy modeling approach for the numerical solution of heat transfer problems. However, the curves are non-smooth, discrete signals. They are affected by noise in the heat capacity data and should not be used as input to continuous simulation models. This contribution proposes an alternative method based on spline approximation for the generation of consistent and smooth phase fraction–temperature, apparent heat capacity–temperature and enthalpy–temperature curves. Applications are presented for two commercial paraffins from Rubitherm GmbH considering heat capacity data from Differential Scanning Calorimetry and 3-layer-calorimetry. Apparent heat capacity models are validated for melting experiments using a compact heat exchanger. The best fitting models and the most efficient numerical solutions are obtained for heat capacity data from 3-layer-calorimetry using the proposed spline approximation method. Because of these promising results, the method is applied to melting data of all 44 Rubitherm paraffins. The computer code of the corresponding phase transition models is provided in the Supplementary Information.

Accurate heat capacity data at phase transitions from relaxation calorimetry

Cryogenics ◽  
2010 ◽  
Vol 50 (10) ◽  
pp. 693-699 ◽  
Author(s):  
Hal Suzuki ◽  
Akira Inaba ◽  
Christoph Meingast
Keyword(s):  
Heat Capacity ◽  
Phase Transitions ◽  
Heat Capacity Data ◽  
Relaxation Calorimetry ◽  
Capacity Data

scholarly journals Synthesis, characterization and thermal behaviour on solid pyruvates of light trivalent lanthanides

2007 ◽  
Vol 32 (4) ◽  
pp. 49-54 ◽  
Author(s):  
A. B. Siqueira ◽  
C. T. de Carvalho ◽  
E. C. Rodrigues ◽  
E. Y. Ionashiro ◽  
G. Bannach ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Thermal Decomposition ◽  
Infrared Spectroscopy ◽  
Solid State ◽  
Thermal Behaviour ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Trivalent Lanthanides ◽  
Light Trivalent Lanthanides ◽  
Derivative Thermogravimetry

Solid State Ln-L compounds, where Ln stands for light trivalent lanthanides (La - Gd) and L is pyruvate, have been synthesized. Thermogravimetry and derivative thermogravimetry (TG/DTG), differential scanning calorimetry (DSC), X-Ray powder diffractometry, infrared spectroscopy, elemental analysis, and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, ligand denticity, thermal behaviour and thermal decomposition of the isolated compounds.

scholarly journals Synthesis, characterization and thermal behaviour on solid pyruvates of some bivalent metal ions.

2018 ◽  
Vol 34 (2) ◽  
pp. 15
Author(s):  
Adriano Buzutti De Siqueira ◽  
Cláudio Teodoro De Carvalho ◽  
Elias Yuki Ionashiro ◽  
Massao Ionashiro
Keyword(s):  
Differential Scanning Calorimetry ◽  
Thermal Decomposition ◽  
Infrared Spectroscopy ◽  
Solid State ◽  
Thermal Behaviour ◽  
Scanning Calorimetry ◽  
Bivalent Metal ◽  
X Ray ◽  
Bivalent Metal Ions ◽  
Derivative Thermogravimetry

Solid state M-L compounds, were M stands for bivalent Mn, Fe, Co, Ni, Cu, Zn and L is pyruvate, have been synthesized. Thermogravimetry and derivative thermogravimetry (TG/DTG), differential scanning calorimetry (DSC), X-Ray powder diffractometry, infrared spectroscopy, elemental analysis, and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, ligand denticity, and thermal decomposition of the isolated compounds.

scholarly journals Synthesis, characterization and thermal behaviour of solid-state compounds of 4-methoxybenzoate with lanthanum (III) and trivalent lighter lanthanides

2006 ◽  
Vol 31 (1) ◽  
pp. 21-30 ◽  
Author(s):  
E. C. Rodrigues ◽  
A. B. Siqueira ◽  
E. Y. Ionashiro ◽  
G. Bannach ◽  
M. Ionashiro
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Thermal Decomposition ◽  
Differential Thermal Analysis ◽  
Solid State ◽  
Thermal Behaviour ◽  
Polymorphic Transformation ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Lighter Lanthanides

Solid-state M-4-MeO-Bz compounds, where M stands for trivalent La, Ce, Pr, Nd and Sm and 4-MeO-Bz is 4-methoxybenzoate, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, polymorphic transformation, ligand's denticity, thermal behaviour and thermal decomposition of the isolated compounds.

Unprecedented transformation of [I−·I3−] to [I42−] polyiodides in the solid state: structures, phase transitions and characterization of dipyrazolium iodide triiodide

2015 ◽  
Vol 44 (42) ◽  
pp. 18447-18458 ◽  
Author(s):  
M. Węcławik ◽  
P. Szklarz ◽  
W. Medycki ◽  
R. Janicki ◽  
A. Piecha-Bisiorek ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Phase Transitions ◽  
Solid State ◽  
Dielectric Measurements ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Solid State Structures

Dipyrazolium iodide triiodide, [C3N2H5+]2[I−·I3−], has been synthesized and studied by means of X-ray diffraction, differential scanning calorimetry, dielectric measurements, and UV-Vis spectroscopy.

scholarly journals Thorough investigation on the high-temperature polymorphism of dipentyl-perylenediimide: thermal expansion vs polymorphic transition.

2021 ◽  
Author(s):  
Francesco Marin ◽  
Serena Tombolesi ◽  
Tommaso Salzillo ◽  
Omer Yaffe ◽  
Lucia Maini
Keyword(s):  
Thermal Expansion ◽  
High Temperature ◽  
Solid State ◽  
Thermal Behaviour ◽  
Variable Temperature ◽  
Negative Thermal Expansion ◽  
Thermal Characterization ◽  
Polymorphic Transition ◽  
State Transitions ◽  
Scanning Calorimetry

N,N’-dipentyl-3,4,9,10-perylendiimide (PDI-C5) is an organic semiconducting material which has been extensively investigated as model compound for its optoelectronic properties. It is known to be highly thermally stable, that it exhibits solid-state transitions with temperature and that thermal treatments lead to an improvement in its performance in devices. Here we report a full thermal characterization of PDI-C5 by combination of differential scanning calorimetry, variable temperature X-ray diffraction, hot stage microscopy, and variable temperature Raman spectroscopy. We identified two high temperature polymorphs, form II and form III, which form respectively at 112 °C and at 221 °C and we determined their crystal structure from powder data. Form II is completely reversible upon cooling with low hysteresis, while form III revealed a different thermal behaviour upon cooling depending on the technique and crystal size. The crystal structure’s features of the different polymorphs are discussed and compared, and we looked into the role of the perylene core and alkyl chains during solid-state transitions. The thermal expansion principal axis of PDI-C5 crystal forms is reported showing that all the reported forms possess negative thermal expansion (X1) and large positive thermal expansion (X3) which are correlated to thermal behaviour observed.

Heat Capacity of K3LnCl6 Compounds with Ln = La, Ce, Pr, Nd

1999 ◽  
Vol 54 (3-4) ◽  
pp. 229-235 ◽  
Author(s):  
M. Gaune-Escard ◽  
L. Rycerz
Keyword(s):  
Experimental Data ◽  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Heat Capacity ◽  
Phase Transitions ◽  
Liquid Phase ◽  
Temperature Dependence ◽  
Heat Capacities ◽  
Scanning Calorimetry ◽  
The Enthalpy Of Formation

The heat capacities of the solid and liquid K3LnCl6 compounds (Ln = La, Ce, Pr, Nd) have been determined by differential scanning calorimetry (DSC) in the temperature range 300 -1100 K. Their temperature dependence is discussed in terms of the phase transitions of these compounds as reported in literature. The heat capacity increases and decreases strongly in the vicinity of a phase transition but else varies smoothly. The Cp data were fitted by an equation which provides a satisfactory representation up to the temperatures of Cp discontinuity. The measured heat capacities were checked for consistency by calculating the enthalpy of formation of the liquid phase, which had been previously measured. The results obtained compare satisfactorily with these experimental data.

scholarly journals High-temperature heat capacity ErInGe2O7 and TbInGe2O7 in the range 350-1000 K

2019 ◽  
Vol 486 (2) ◽  
pp. 193-196
Author(s):  
L. T. Denisova ◽  
A. D. Izotov ◽  
Yu. F. Kargin ◽  
L. A. Irtugo ◽  
V. V. Beletskiy ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Heat Capacity ◽  
High Temperature ◽  
Solid State ◽  
Thermodynamic Properties ◽  
Solid State Reactions ◽  
Effect Of Temperature ◽  
Scanning Calorimetry ◽  
High Temperature Heat Capacity ◽  
Temperature Heat

SmFeGe2O7 germanate was obtained by solid-state reactions from stoichiometric mixtures of starting oxides with multistage firing within 1273-1473 K. The effect of temperature on the heat capacity of the compound was studied using differential scanning calorimetry. Based on the dependence Cp = f(T), its thermodynamic properties are calculated.

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