42
LMS Issue 4 | 2014
Thermal Analysis
Get the Advantage
D
VS Advantage combines the best
in microbalance, gas f low and
vapour measurement technologies to
deliver supreme performance, accuracy
and repeatability.
The Advantage uses a dry carrier
gas and the user can select one of two
vapour sources. Precise control of the
ratio of saturated and dry carrier gas
flow is enabled with mass flow control
combined with the use of unique realtime vapour concentration monitoring
for both water and organics. A known
concentration of the selected vapour
then flows over a sample suspended from
a recording ultra-microbalance, which
measures the weight change caused by
sorption or desorption of the vapour
molecule. It is these dynamic flow conditions that enable the sorption/desorption
process to be so rapidly studied.
The specific sample may be preheated if desired as a further experimental option, which in some cases
may speed up the analysis time as in the
case of bulk absorption or the drying of
inorganic hydrates. This heating can be
as a single step or at a controlled ramp
rate of temperature.
The temperature of the whole system
is user-selectable and precisely controlled under closed loop conditions to
ensure that the solute vapour pressure at
the sample is constant. Isolation valves
at the solvent reservoirs ensure there is
no solute contamination of the sample
area when p/pº of zero is requested,
ensuring that a true p/pº zero is always
obtained. The incredible sensitivity and
precision of the Advantage enables the
use of very small samples (typically 1 30mg) thus allowing equilibrium to be
reached more quickly.
There is a fully automated inert gas
purge facility and organic leak sensor
system shut down interlock in the case of an
accidental organic vapour
release. The instrument is
fully programmable and
controlled by the DVS Advantage software through a smart operator interface
that meets the highest standards of data
integrity and security. A full suite of data
analysis modules running under Excel®
allow one-click calculations and reports
to be generated. ⚛
Wirsam Scientific
Tel:
011-482‑1060 / 021-386‑9020 /
031-709-0199 / 041-365‑2060 / 016-931‑1731
Email: wirsamjb@wirsam.com
Breakthrough in DSC Sensor Technology
D
ifferential Scanning Calorimetry
(DSC) is defined as the measure
ment of the difference between the heat
flows from the