opti-sciences OS1p, Руководство пользователя

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Setting saturation pulse duration
Duration is the time that the saturation flash is turned on. For higher plants, times of 0.5
to 1.5 seconds have been used. For algae and cyanobacteria, the optimal saturation pulse
duration is 25 to 50 msec (Schreiber 1995).
Automatic routine for setting of the saturation pulse duration
The OS1p will always measure the optimal duration time as long as the duration is set
long enough for a particular type of plant. The instrument has an automated software
routine that always takes a rolling average of the top continuous eight points on the top of
the saturation pulse. This represents a time duration of twenty five milliseconds. As a
result, this automated routine works for higher plants, algae, and cyanobacteria if the
duration is set long enough.
Manual setting of the saturation pulse duration
of the saturation pulse. The default value is 0.8 seconds and works well for most higher
plants tested. If the duration is not long enough, then PSII will not be fully saturated at
any light intensity, and Fm values are reduced. On most modulated chlorophyll
fluorometers (but not the OS1p), if the duration is too long, the saturation pulse top
becomes subject to a type of NPQ that rounds the tailing edge of the saturation peak and
also reduces the average Fm value. The Ideal saturation pulse top is flat on the top with
the trailing edge rounding minimized (Roseqvist and van Kooten 2006).
The saturation pulse duration is adjustable between 0.1 and 2.0 seconds. To adjust the
duration, touch the upper right graphic display window of the Yield protocol measuring
window. Since the automated routine is always running on the OS1p, it also works for
algae and cynanobacteria, even when the duration is set longer.
RLC Measuring Screen ETR Test Calculation Screen
By pressing the Flash Width button one goes to a keyboard screen and allows the
saturation pulse duration to be adjusted between 0.1 and 2.0 seconds. Press “Ent”