`Fractional heating' differential scanning calorimetry: a tool to study energetics and kinetics of solid-state reactions in photoactive systems with distributed parameters

1998 ◽  
Vol 238 (2) ◽  
pp. 343-351 ◽  
Author(s):  
Juliusz Sworakowski ◽  
Stanislav Nešpůrek
1995 ◽  
Vol 398 ◽  
Author(s):  
R.R. Chromik ◽  
E. J. Cotts

ABSTRACTUsing differential scanning calorimetry, supplemented by measurements from scanning electron microscopy images, we have investigated solid state reactions in Pd/Sn multilayer composites to form PdSn4 and PdSn3. Planar diffusion couples of Pd and Sn were prepared by means of mechanical co-deformation in a rolling mill. A phase formation sequence was determined using differential scanning calorimetry and x-ray diffraction. Growth of the PdSru phase was studied from room temperature to the melting point of Sn. For temperatures between 430 and 460K diffusion limited growth of PdSn4 was observed. From heat flow data over this limited temperature range, the form of the reaction constant was found to be k2 −k0 exp(−Ea / kbT), where k0= 0.16 cm2/s and Εn= 0.8 eV/atom. Also determined was a heat of formation, ΔHf = −27±1 kJ/mol for PdSn4 from Pd and Sn.


2019 ◽  
Vol 486 (2) ◽  
pp. 193-196
Author(s):  
L. T. Denisova ◽  
A. D. Izotov ◽  
Yu. F. Kargin ◽  
L. A. Irtugo ◽  
V. V. Beletskiy ◽  
...  

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.


2019 ◽  
Vol 487 (6) ◽  
pp. 640-643
Author(s):  
L. T. Denisova ◽  
A. D. Izotov ◽  
Y. F. Kargin ◽  
L. A. Irtugo ◽  
V. V. Beletskiy ◽  
...  

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.


Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 292
Author(s):  
Yazhu Ma ◽  
Yubing Zhang ◽  
Feng Liu

Solid-state phase transformations like crystallization of amorphous alloys can be described by an analytical model incorporating a nucleation index a. However, this model cannot be used to examine isochronal transformations with abrupt changing of enthalpy differences performed with differential scanning calorimetry. Based on the model, a non-isokinetic approach is proposed and applied to analyze the isochronal crystallization kinetics of Fe85B15 amorphous alloy. The approach enabled us to obtain the kinetic parameters and activation energies for nucleation and growth.


Sign in / Sign up

Export Citation Format

Share Document