PerkinElmer Spotlight 200, Руководство пользователя

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Techniques for Collecting Spectra . 67
Using a Hot/Cold Stage
An optional hot stage enables you to study temperature-dependent phenomena in
microsamples. A hot stage consists of a temperature controller and a heating block that
accepts infrared windows. The heating block contains an integral thermocouple, and the
temperature is digitally displayed in degrees Celsius on the controller.
A hot stage can heat samples in 1 degree increments. The maximum temperature that can
be achieved depends upon the type of hot stage being used; see Accessories on page 119
for details. A target temperature can be selected and maintained.
A hot stage is held in the slide clip on the sample stage of the microscope. The microscope
requires no modifications to accept the hot stage.
A hot stage enables you to study phase transitions and temperature-dependent chemical
reactions. Infrared microscopy can provide detailed molecular structural information for
systems undergoing phase transitions; this information is not available from thermal data
only. Polymers, pharmaceuticals and liquid crystals are examples of materials where
investigations of phase transition are important.
NOTE:
Some types of hot stage can be used with a cooler. The cooler uses liquid nitrogen to
reduce the temperature of the stage down to − 196 °C. See
Accessories
on page 119
for details
Collecting the Spectrum of a Thick Sample
Lowering the stage using the Z -control on the joystick enables you to focus on a thick
sample. For very thick samples you may have to remove the lower cassegrain assembly; then
only the reflectance method can be used to view the sample and collect spectra.
To collect the spectrum of a thick sample
1. Click Zero on the Setup Microscope Advanced tab.
The lower cassegrain moves to the position where the infrared beam is focused if no
sample is on the stage.
2. Move the sample stage to its highest possible position.
3. Click Park on the Setup Microscope Advanced tab.
The lower cassegrain bracket moves down to a lower position.
4. Release the locking lever located on the right side on the back of the lower cassegrain
assembly (Figure 20).