Waters Xevo TQD, Руководство оператора, обзор и техническое обслуживание

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1-10 Specifications and Operating Modes
APCI, or dual mode, which switches rapidly between APPI and APCI
ionization modes.
NanoFlow source
“NanoFlow” is the name given to several techniques that use low flow rate
electrospray ionization. The NanoFlow source allows electrospray ionization
in the flow rate range 5 to 1000 nL/min. For a given sample concentration, the
ion currents observed approximate those seen in normal flow rate
electrospray. However, for similar experiments, NanoFlow’s significant
reduction in sample consumption accompanies significant increases in
sensitivity.
The following options are available for the spraying capillary:
• Universal nebulizer sprayer (Nano-LC).
This option is for flow injection or for coupling to nano-UPLC. It uses a
pump to regulate the flow rate downward to 100 nL/min. If a syringe
pump is used, a gas-tight syringe is necessary to effect correct flow rates
without leakage. A volume of 250 µL is recommended.
• Borosilicate glass capillaries (nanovials).
Metal-coated, glass capillaries allow the lowest flow rates. Usable for
one sample, they must then be discarded.
• Capillary Electrophoresis (CE) or Capillary Electrochromatography
(CEC) sprayer. This option uses a make-up liquid at the capillary tip
that provides a stable electrospray. The make-up flow rate is less than
1 µL/min.
Atmospheric solids analysis probe (ASAP)
The ASAP facilitates rapid analysis of volatile and semivolatile compounds in
solids, liquids, and polymers. It is particularly suited to analyzing low-polarity
compounds.The ASAP directly replaces the electrospray or IonSABRE II
probe in the instrument’s source housing and has no external gas or electrical
connections.
See the
Atmospheric Solids Analysis Probe Operator’s Guide Supplement for
further details.