Thermo Scientific Evolution 200 Series User Manual page 83

Thermo Scientific
Measurement Tab for Rate
Feature Description
Integration time How long the system acquires and averages data to obtain each data
point at each measured wavelength for single and multicell
experiments or at each data interval for scan experiments.
Dwell time How long the sample remains in the light beam.
Use this setting to vary the number of data points collected per cell
per cycle. Dwell time is always a multiple of integration time (see
above). Dwell time can be very useful when performing multicell
rate measurements. This is because the cell changer accessory will
position a cell in the light beam for a specified period of time (dwell
time), rather than moving back and forth between cells and
increasing the time between measurements (when no sample is in
the light beam).
For example, if the integration time is 0.1 second and dwell time is
0.5 second, five data points will be recorded for each cell before the
cell changer moves to the next cell. For fairly fast reactions, multiple
samples can be measured, with over ten times as many data points
acquired within a short time. This can improve the accuracy of rate
calculations for faster multicell rate measurements.
Time unit Determines the time unit used in the stages table (see below).
Allow multiple stages Allows the use of the specified number of measurement stages, over
which the frequency of data acquisition can be determined. For
example, if a reaction has two components, the first component
could be fast and require a high data density. The second component
could be much slower and longer lived, therefore requiring a lower
data density. Defining multiple stages enables the use of the proper
data density over a given period of time.
For single and multiple wavelength experiments only.
Stages table Defines for each stage the start time, end time and interval (how
frequently a measurement is made). For example, using an interval
of 10 seconds would measure the sample every 10 seconds from the
start time to the end time. In a multicell experiment the interval
setting is the measurement interval for each sample.
For single and multiple wavelength experiments only.
Cycle time Time between each measurement cycle. For scan experiments only.
Click Settings in Rate to display the Measurement tab in
the right pane.
2
INSIGHT Software
Operation
Evolution 200 Series User Guide 69