PerkinElmer DSC 4000, Инструкция по установке и эксплуатации оборудования

Страница: 54 / 86

54 . DSC 4000 Installation and Hardware Guide
DSC 4000
The DSC 4000 Differential Scanning Calorimeter is a single-furnace, heat-flux DSC. Heat flow
is determined by measuring a temperature difference over a very accurately known thermal
resistance. This analyzer is used to characterize materials, design products, predict product
performance, optimize processing conditions, and improve quality. The DSC 4000 system
permits the direct calorimetric measurement, characterization, and analysis of thermal
properties of materials. Under the control of the Pyris software on your PC, the DSC 4000 is
programmed from an initial to a final temperature through transitions in the sample material
such as melting, glass transitions, solid-state transitions, or crystallization. Usually the
DSC 4000 is programmed to scan a temperature range at a linear rate for the study of these
endothermic and exothermic reactions. Endotherms and exotherms can be shown as an
upward or downward deviation from the baseline.
The DSC 4000 has an integrated cooling system which accepts various types of cold liquids.
This allows operation from –100 °C to 445 °C. The DSC 4000 can be used with a range of
commercial circulating coolers, and for occasional subambient operation can be used with the
Portable Cooling Device.
The DSC 4000 is also upgradeable to the DSC 6000.
Furnace and Sensor Design
A low-mass, alumina-coated aluminum furnace forms the heart of the DSC 4000. The furnace
is designed for ruggedness and resistance to chemical corrosion. Because of its low mass,
the furnace can heat and cool rapidly. A platinum resistance sensing device measures and
controls the furnace temperature.
The atmosphere surrounding the sample is controlled very efficiently since the gas enters
above the sample crucible. This is extremely important when performing oxidative stability
experiments. The purge gas is also preheated resulting in minimal disturbance of the signal.
The sample is placed on a precisely machined sensor disk constructed of 90% nickel/10%
chromium. This rugged and durable disk provides high thermal conductivity and a very low
time constant for superior instrument response. Highly sensitive thermocouples measure the
temperature at both the sample and reference positions. The DSC 4000 accommodates a
wide range of PerkinElmer sample pans. Over two dozen different pan types are available.