You might have misunderstood or misread this publication. There is no relation between temperature and energydensity. Both dimensions are fully independent.
I wonder whether you are referring to a parameter that descibes some physical characteristic of matter. You might be referring to one of such characteristic, namely (spcific) Heat Capacity, (https://en.wikipedia.org/wiki/Heat_capacity) which in SI units is expressed in kJ/(kg .K), where K = 273+°C. Heat Capacity is equal to the ratio of the heat added to (or removed from) an object to the resulting temperature change.