Samples are held in a shallow Inconel dish which is
supported on an adjustable Ni-Cr loop attached to the
oxygen inlet tube. Electrical connections for the firing
circuit are made through a connector which slides into
the central terminal and bomb support stand.
The Oxygen Connection
Oxygen is supplied to the 1109A Bomb with a
Parr 1824 Filling Connection which provides all of
the valves and fittings needed to fill the bomb from
a commercial oxygen tank, including an automatic
relief valve to prevent overcharging.
An Effective Thermal Jacket
Effective static insulation is provided in these
calorimeters by using a fully silvered glass Dewar
as the calorimeter vessel. This vacuum flask holds
the 1109A Semimicro Bomb in 460 grams of water.
It is supported within a stainless steel air can which
is easily removed for filling or cleaning. The air can
is surrounded by a plastic foam block, and the entire
assembly is mounted in a sturdy aluminum case.
A thermistor probe and stirrer are mounted on
the calorimeter cover and remain attached to the
cover when the calorimeter is opened. A small motor
attached to the side of the case drives the stirring shaft
at a constant speed (approx. 450 rpm) through a flat,
ribbed drive, belt which is easily removed when open-
ing the calorimeter.
Precise Temperature Measurements
Temperature measurements in the 6725 Semimicro
Calorimeter are taken with a Parr 6772 Calorimetric
Thermometer which is described on page 3. In this
application, the thermometer module is included with
the calorimeter.
Cross Section of 1109A Bomb
1109A Semimicro Oxygen Bomb
B u l l e t i n 6 7 0 0
9
1 - 8 0 0 - 8 7 2 - 7 7 2 0
S o l u t i o n a n d S e m i m i c r o C a l o r i m e t e r s
