Biology Reference
In-Depth Information
The numerical values of
k
37
-
k
48
are reported in Table
3.1
.They were calculated
with the above
k
equations from the same Soret excitation spectra used to calculate
k
1
-
k
12
.
Every
k
value reported in Table
3.1
is the mean of 15-25 different
determinations.
By substituting the numerical values of
k
37
-k
48
into the four simultaneous
equations described above and by solving for Pheo(bide)
b
(F660 E438) the follow-
ing equation was obtained:
Pheo
ð
bide
Þ
b
ð
F660 E412
Þ¼
0
:
001
ð
F674 E412
Þþ
1
:
152
ð
F660 E438
Þ
36
0
Þ
0
:
423
ð
F674 E433
Þ
0
:
420 F660 E460
ð
Þ
ð
3
:
3.4.4.2 Determination of the Reliability of Eq. (
3.36
0
) and
Determination of Its X
1
and Sx
1
Correction Factors
The reliability of Eq. (
3.36
0
) was tested via the following equation:
Pheo
ð
bide
Þ
b
ð
F660 E438
Þ¼
½
A
4
þð
A
4
Þð
X
2
Þ=
100
ð
A
4
Þð
S
X2
Þ=
100
(3.36)
Where:
A
4
¼
Eq. (
3.36
0
)
[(A
4
)(X
4
)/100]
are relative concentration-correction factors, which vanish as
the X values approach zero. The X
4
correction values are listed in Table
3.5
and
their derivation and usage is as for Eq. (
3.33
). Finally, the last term in Eqs. (
3.36
),
i.e
.
(A
4
) (Sx
4
)/100 refers to the standard deviation (Sx
4
) of the determinations
expressed as a percentage of the pigment content.
The Sx
2
values are also listed in Tables
3.5
and their derivation is as discussed
for Eq. (
3.33
).
The determination of the X
4
and Sx
4
correction values for various relative
concentrations of Pheo(bide)
a
are reported in Table
3.5
. The mean per cent error
(X
4
) and standard deviation (Sx
2
)rangedfrom
¼
1.1 % + 0.6 % for pure solutions of
Pheo
b
to
22.0 % for mixtures containing 14 % of Pheo
b
. The perfor-
mance of Eq. (4
0
) broke down for mixtures containing 6 % or less of Pheo(bide)
b
and
its use is not recommended for these low concentrations of Pheo(bide)
b.
Based on the results of Table
3.5
, it is however recommended that for precise
calculations with Eq. (
3.4
), the proper values for X
4
and Sx
4
should be calculated by
interpolation from Table
3.5
.
For
14.0 %
less rigorous calculations an overall average value of
9.5 % for
X
4
9.7 % for Sx
4
may be utilized.
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