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Date: | Tue, 3 May 2005 12:37:23 +0200 |
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hello to all,
>It enabled me to run samples on a 2 days on, 1 day off or 5 days on, 1 day
>off cycle; depending, as Deborah points out on actual sample throughput (ca.
>200 individual injections per re-oxidisation cycle sounds about right for a
>Finnigan combustion tube).
Our's is an PDZ Europa, now Sercon GC-MS (ANCA SL /2020).
Deborah
>
>
>> -----Original Message-----
>> From: Stable Isotope Geochemistry
>> [mailto:[log in to unmask]] On Behalf Of Deborah Rupprecht
>> Sent: 03 May 2005 10:21
>> To: [log in to unmask]
>> Subject: aging of Cu-tube: re-oxidising
>>
>>
>> Dear all,
>>
>> using a GC-MS, we are re-oxidising the tube when copper is
>> nearly completely black (we check this regularly) by heating
>> the tube from 650 to 750 °C and connecting to O2/N2 gas
>> ("Protec") for 10-15 minutes, then cooling down to 650°C (about 30').
>>
>> This is enough for next about 200 samples (two days,
>> depending on re-aging). If we have to re-oxidise it every
>> day, we change it completely. One tube is working in average
>> for about 1000 analysis. We did not try to re-oxidise it for
>> 12 hours; maybe we would not need to re-oxidise it all two
>> days. Good idea.
>>
>> Greetings,
>> Deborah
>> ********************
>> Deborah Rupprecht
>> Institute of Plant Nutrition
>> Karlrobert-Kreiten-Str. 13
>> 53115 Bonn, Germany
>> Phone (+049) 0228-73-3640, -1631
>> ********************
>>
>
********************
Deborah Rupprecht
Institute of Plant Nutrition
Karlrobert-Kreiten-Str. 13
53115 Bonn, Germany
Phone (+049) 0228-73-3640, -1631
********************
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