Micromass Quattro Ultima, Руководство пользователя

Страница: 86 / 227

Setting up a Full Scan Function
The full scan function editor, activated by pressing or by selecting
MS Scan from the Functions menu, is used to set up centroid, continuum and
MCA functions.
Mass (m/z)
Start Mass and End Mass specify the masses at which the scan starts and stops.
Start Mass
must be lower than
End Mass
.
Start Time and End Time specify the retention time in minutes during which this
function becomes active, and data are acquired.
Cone Voltage
When Use Tune Page is checked, the cone voltage set on the tune page at the start
of the acquisition is used.
The cone voltage value cannot be altered during acquisition by typing new
values into the tune page, since the new values are not downloaded during
acquisition. This can only be done by acquiring from the tune page.
To apply a ramp to the cone voltage:
Check
Use Cone Voltage Ramp and
press CV Ramp to load the
cone ramp dialog.
The four parameters define a gradient
for the cone voltage which is then
extrapolated to cover the full mass
range of the function.
Method
Ionization Mode specifies the
ionization mode and polarity to be used during acquisition.
Data
specifies the type of data to be collected and stored on disk. There are three
options:
•
Centroid stores data as centroided, intensity and mass assigned peaks. Data are
stored for every scan.
•
Continuum . The signal received by the interface electronics is stored regularly
to give an analog intensity picture of the data being acquired. Data are not
centroided into peaks, but are stored for every scan.
Due to the fact that data are acquired to disk at all times, even when no peaks
are being acquired, continuum data acquisition places some extra burden on the
Data Acquisition
Page 86
Quattro Ultima
User's Guide