HP 5973 MSD Hardware Manual page 117

M
Maintenance, 93
CI ion source cleaning, 95
cleaning reagent gas supply tubing, 102
connecting the vacuum gauge controller, 100
foreline pump, 96
increased need for ion source cleaning, 94
methane/isobutane gas purifier, 97
purging the CI calibration valve after refilling
the PFDTD vial, 99
refilling the CI calibrant vial, 98
Methane
PCI methyl stearate spectrum, 24
setting up gas flow, 54
Methane, purity specification, 10
Methane/isobutane gas purifier, 12
replacing, 97
Methyl stearate, spectra for methane and ammonia
PCI, 24
Monitoring vacuum manifold pressure, 62
MSD Reference Collection CD-ROM
CI ion source cleaning, 95
N
NCI. See Negative CI
Negative CI
analyzer voltage polarities reversed, 30
autotune, 58
buffer gas, 30
dissociative electron capture, 33
effect of contamination, 32
electron capture, 32
ion pair formation, 33
ion-molecule reactions, 33
sensitivity, 32
theory, 30
thermal electrons, 30
Noise declaration, inside front cover
P
Part numbers, inside front cover
See also Parts
Parts, 103
CI interface, 106
CI ion source, 108
ferrules, 112
flow control module, 110
GC/MSD interface, 106
miscellaneous, 113
reagent gas flow control module, 110
to order, 104
PCI. See Positive CI
PFDTD, 8
avoiding persistent background of, 17
Positive CI
addition, 28
charge exchange, 29
hydride abstraction, 28
reagent ion background, 24
theory, 24
Pressure
CI ion source, 14, 24
indicated vs. absolute, 62
Ion source, for CI, 12
monitoring vacuum manifold, 62
Proton affinity
importance in PCI, 26
organic compound table, 27
reagent gas table, 27
Proton transfer, 26
Pumpdown
hydrogen carrier gas warning, 40
procedure, 40
Pumpout slots, in CI ion source, 14
Index
117