Heike Kamerlingh Onnes when his notebook was deciphered a century later). He reported that ""Mercury has passed into a new state, which on account of its extraordinary electrical properties may be called the superconductive state"". He published more articles about the phenomenon, initially referring to it as ""supraconductivity"" and, only later adopting the term "superconductivity". Kamerlingh Onnes received widespread recognition for his work, including the 1913 Nobel Prize in Physics for (in the words of the committee) ""his investigations on the properties of matter at low temperatures which led, "inter alia", to the production of liquid helium"". Some of the instruments he devised
Enthalpy older term "heat content", a term which is now mostly deprecated as misleading, as refers to the amount of heat absorbed in a process at constant pressure only, but not in the general case (when pressure is variable). Josiah Willard Gibbs used the term "a heat function for constant pressure" for clarity. Introduction of the concept of "heat content" is associated with Benoît Paul Émile Clapeyron and Rudolf Clausius (Clausius–Clapeyron relation, 1850). The term "enthalpy" first appeared in print in 1909. It is attributed to Heike Kamerlingh Onnes, who most likely introduced it orally the year before, at the first