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MGA#5 is a Unique SRI Configuration
(SRI MG5 2016-Update18 )
 (2.3Mb)
* MG5 Update Oct2022 * -proposed upgrade SRI-EPC(s) radioactive license required ( for SRIs ECD ) !
> MG#6? * maybe? ;& CT specs >> MFC for SRI EPCs)
* to minimise air diffusion within the GC.
HighPurity mini Pressure Regulator (SS Diaphram recommended (or on Gas Cylinder)
Getter Gas Purifier ( mounted close to GC essential)
Silcosteel loop, columns & transfer line recommended >> ppB sensitivity 104 range linearity ?
- TCD for ~100ppM LOD to (mid) percent
- FID-Methaniser down to low ppM CO/CO2
- HID for Trace Gas Analysis ( low ppM (SRI >10 ?)
- S-Cpds requires a FID-FPD (optional)
- HS-D maybe a limitation ( eg ethanol Max); OR may require other HaySep (Q, N, S etc ) columns for limited polar compounds . . .
> also try > .
- Restek MicroPacked HayeSep columns or PLOT Columns as options
Dual Oven extra possibity 8619D as a MG#5 option ?
MS in 2nd ( easier bake-out) > 250degC HS-D ( Max 200degC )
Trace Gas Analysis (low ppB) - a “custom” far more specialised
App & specs
> ASK! ( can use existing electromterer and pulse control box depending on SRI detector space available ! )
- requires 3rd Det SRI-HID ( or VICI Valco miniPDD ?)
> better for“trace” permanent gases & a different format GC eg SRI 8610V
- SRI HID ??? H2 > ASK SRI ? for specs re sensitivity - but not necessarily recommended by SRI for “trace gas”
- CT with Modes ( gas purity and NO EPC; SS Mass Flow Controller ! for . . . ( MG5 proposed CT-Update ).
- allows “quantitative ( H2 & O2/N2 (%) HID Matrix & Carrier Gas, High Purity Regulators & Getter Gas Purifier for LODs <10ppM ?
- “SHINCarbon ST - DOES offer a one-column analysis \of O2/N2 CO/CO2 > but with compromises !
BUT NOT without it’s own idiosynchrasies / problems
eg AR / O2 No! / C2 max at >300C ?;
O2/N2 requires LDV HID and > 4m Packed Column
> SRI-TCD > marginal ?
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Multi-Gas Analysis
- NO Simple Answers ! > many Options >
this applies to ALLGCs
& any OEM brand !
- H2 Quantitation requires use of Argon Carrier Gas NOT He ( anomoulous non-linearity effects with H2 @ ~1-6% )
( non quantitaive peak reversl with He ( 1-10%)
- > TCD/He almost useless requires low Dead-volume VICI HID Detector for CAPILLARY PEAKs
- Ar / O2 separation is very difficult and requires PLOT MS5A Column - some other limitations
- NEW ! Methane CO2 elutes on micropacled Shincarbon HT ( 100/120# 0.75mmID 2m but TCS a limitation with deadvolme resolution loss for O2/N2 separation !
- MS13X recommended for CO@ NOE ewltes ~175-200C but susceptible to legth bakeout occasionaly deoene on sample PPM and ware content
- MS5A becomes deactivated if repetiitive runs and with excessive water/CO2 in matrix Gas
> dual Oven 8610D optional (??? ASK!) re GasValves as well ? !
- S-cpds can deactivate the Methaniser Answer ? ASK!
- excess water / humid samples ( we suggest> a Nafion Drier on the sample stream prior to GC )
ASK for some (more) ANSWERS !
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from ~31Mar24+
