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Chapter IV Thermal Studies of …..
From the thermo-grams the number of water molecules associated with pure
and amino acids doped crystals was estimated, which is shown in table (4.1).
It can be observed that as the doping of amino acid increases the bulk values
of water molecules attached with the crystals increases.
Table: 4.1 Number of water molecules for pure and amino acids doped KDP crystals.
Sample
No. of water
molecule
Pure KDP Crystal 0.43
KDP + 0.3% wt. L-histidine
KDP + 0.4% wt. L-histidine
4.4 Kinetic and Thermodynamic Parameters:
The use of thermo-gravimetric data to evaluate the kinetic parameters
of solid-state reactions involving weight loss has been investigated by many
workers [21-24]. If the pyrolysis occurs through a many-stepped mechanism,
usually, the shape of the curve can be determined by the kinetic parameters
of pyrolysis, such as order of reaction, frequency factor and energy of
activation. Kotru et al [25] reported the kinetics of solid-state decomposition of
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0.59
0.76
KDP + 0.5% wt. L-histidine 0.82
KDP + 0.3% wt. L-threonine
KDP + 0.4% wt. L-threonine
KDP + 0.5% wt. L-threonine
KDP + 0.3% wt. DLmethionine
KDP + 0.4% wt. DLmethionine
KDP + 0.5% wt. DLmethionine
0.45
0.49
0.51
0.74
0.83
0.86