Chemistry Reference
In-Depth Information
a
b
c
k
d
Fig. 6.2a-d
Plots used to obtain the kinetic equations.
Δ
T
=
Δ
T
(
ω
,
t
) (
a
),
T
=
T
(
ω
,
t
) (
b
),
η
=
η(ω
,
t
) (
c
),
˙
η =
˙
η(ω
,
t
) (
d
)
line
η
k
= const yields
i
points with abscissas
t
1
,
t
2
,
t
i
. Each abscissa
t
i
corre-
sponds to one value of
T
i
and ˙
η
=
η
i
(Fig. 6.2b, d). Thus one obtains a locus of points
in the ˙
η
−
T
coordinates that form a plot of ˙
η
i
against
T
. Since each value of
η
1
,
η
2
,
η
k
corresponds to the curve ˙
η
(
T
), one obtains a set of
k
curves ˙
η
= ˙
η
(
T
) at
η
= const representing the graphical form of ˙
η
= ˙
η
(
T
,
η
) (Fig. 6.3a). The number
of experimental points on the ˙
η
(
T
) curve at
η
= const equals the number of exper-
iments
i
for various heating rates
ω
i
. For processes that comprise one stage overall,
data (Fig. 6.3a) can be presented as an Arrhenius anamorphosis in ln ˙
T
−
1
(
K
−
1
)
η
−
coordinates at
η
= const (Fig. 6.3b). The temperature interval for the dependence
˙
=
˙
η
η
(
T
,
η
) can be widened by extrapolation (dotted lines in Fig. 6.3b).
