Thermo Scientific AI 3000, Руководство по эксплуатации

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4
AI 3000/AS 3000 II Control
Guidelines for Programming with Different Injectors
Thermo Scientific AI 3000/AS 3000 Sampling System - Operating Manual 71
Nano-Volumes Injections in S/SL Inlets
Injections of sample volumes below 0.1-0.2
μ
L in GC SSL inlets is very attractive when the
dilution with a solvent is not desired and/or the main component easily overloads the capillary
column even at high split ratios. Examples of such applications are analyses of essential oils or
petroleum fractions.
The reduction of the injection volume to the sub microliter range using a standard
autosampler, like the AI 3000/AS 3000 II unit, is achievable by exploiting the low capacity
syringe (0.5
μ
L) and the tapered liner provided in the Nano-Volumes Kit for S/SL Inlet System .
High accuracy and repeatability injecting nano-volumes are achievable by exploiting the “ Cold
Needle ” injection mode.
For injection volumes higher than 0.2-0.3
μ
L use a 5 (or 10)
μ
L syringe and a standard split
or splitless liner (possibly packed with glass wool whenever you inject in “ Cold Needle ” mode).
In summary, use the following guideline to choose the best syringe capacity for your injections
with the AI 3000/AS 3000 II autosampler. See
Table 15 for details
Table 14. Summary of Injection Parameters and Conditions
Mode Technique
Column
Insertion
Liner Type Packing of Liner
AI 3000/AS 3000 II Injection
Parameters
Split Hot Needle 40 mm Tubular Liner
(3 or 5 mm ID)
Not required Standard Injection Depth
3-5 sec. Pre-Dwell Time
0 sec. Post-Dwell Time
Cold Needle 40 mm Packing material
at half height Minimum Injection Depth
Dwell Time are
automatically inhibited
Splitless Hot Needle 64 mm Tapered Liner
(3 or 5 mm ID)
Not Required Standard Injection Depth
3-5 sec. Pre-Dwell Time
0 sec. Post-Dwell Time
Cold Needle 50 mm Packing material
at bottom Minimum Injection Depth
Dwell Time are
automatically inhibited
S/SL
Nano-Volumes
1
Cold Needle 40 mm Double Tapered
Liner No Minimum Injection Depth
Dwell Time are
automatically inhibited
1
Only with 0.5
μ
L syringe. For details, refer to the Nano-Volumes Kit for S/SL Inlet System User Guide .