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Fig. 10 Furnace/cryostat unit while operating as an in situ catalyst cell at SSRL. Note all the pipes and tubes at the top of the unit. The yellow and green Polyflow are cooling water in and out. The yellow extension cord is from the current-controlling Variac to the resistance heater. The black and red wires are from the Type K thermocouple. Attached to the top by quick disconnect couplers are
LN2, in and out and catalyst gas flow, in and out. The soft x-ray sample insert is being used; hence, the interior of the furnace/cryostat block is being purged with He.
The basic furnace/cryostat body includes water cooling of the furnace block, provision for He flush or evacuation, Ag Soller slits, fluorescent x-ray ion chamber detector and amplifier. Two different sample holder inserts are available: 1) The cylindrical insert for soft or hard x-rays with sample gas at atmospheric pressure and 2) The boat type sample holder insert for use with x-rays > 7 keV. In this cell the sample pressure can be raised to 100 atmospheres in a Be sample boat. Inside the furnace is a bracket for supporting fluorescent x-ray filters. This assures that the detector operates at maximum sensitivity.
Fig. 11 Furnace/cryostat set up with boat type sample cell insert. Note the vacuum connection. In this mode higher temperatures (to 1000 C) may be achieved with boron nitride or beryllium boat-shaped sample cells.
[ Basic
3-grid ion chamber detector ]
[ New,
double length 5-grid ion chamber detector ]
[ electron-yield
accessory ] [ Hot/cold
accessory ]
[ Furnace/cryostat
body with slits and ion chamber ] [ Boat
type insert ]
[ Cylindrical
insert with removable holder ]
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