Unsupported melting points

Polymer microscopy normally uses a beam current 10 or 100 times less than that used in the example above, so the temperature rise is small. Temperature measurement to confirm this is difficult, but TEM observation of low melting point (40-50°C) crystals is convincing [96]. On the other hand, poor thermal contact with the support or a restricted thermal path, as when an unsupported needle crystal or fiber is illuminated, can produce very high temperatures [97]. 

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