Micromeritics Gemini VII 2390a, Operator'S Manual

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Equipment Description Gemini VII
1-6 239-42828-01 - Dec 2012
Cryogen
Liquid nitrogen is used as the cryogen to cool the sample during analysis. An easy-to-use liquid nitro-
gen transfer system, the Model 021, eliminates the need to pressurize storage Dewars.
Degasser
Micromeritics has the following degassing units available for preparing samples:
• SmartPrep 065
The SmartPrep uses flowing-gas to remove adsorbed contaminants from the sample surface and
pores. It contains six sample ports, each one independently controlled for greater flexibility. It
contains two serial ports, one for connecting to the computer and a second for connecting an
additional SmartPrep. Up to four SmartPreps can be connected in sequence allowing the capability
of up to 24 preparation ports at one time.
The SmartPrep also can be controlled through the analyzer application and is the recommended
degassing unit for the analyzer.
• VacPrep 061
The VacPrep degasses up to six samples at up to 400 ºC with either flowing gas or evacuation.
• FlowPrep 060
The FlowPrep degasses up to six samples at up to 400 ºC with flowing gas.
Refer to
ORDERING INFORMATION
, page
10-1
.
Vacuum Pump
An external vacuum pump equipped with an anti-suckback valve is required for sample analysis with
the Gemini analyzer. Any vacuum source achieving vacuums better than 20 x 10
-3
mmHg at the instru-
ment inlet may be used.
An oil-based or oil-free vacuum pump can be used with the Gemini analyzer. Appropriate vacuum
pumps are available from Micromeritics. Refer to
ORDERING INFORMATION
, page
10-1
.

A device to reduce oil vapor backstreaming is recommended.
The vacuum pump used with the Gemini must have an anti-suckback valve to prevent
oil from being admitted to the instrument should the power fail while the system is
under vacuum. Pumps available from Micromeritics are equipped with an anti-
suckback valve.