An improved accuracy is researched in flat and silicon based nano-calorimeters related to fluid reaction via drop-to-drop
'reaction' or via a steady state in continuous injection of two reactants inside a working chamber. Two types of the experimental
aspects of the sensitivity changes, related to 3-D effects, are described: drop effects and volume rate effects. To increase
the accuracy, well-controlled joule measurements are dissipated in the manufacturer resistance and in several resistances
in carefully controlled experiments. The shape factor (SF) values reduce the manufacturer's joule sensitivity up to fifty per cent. a working methodology is proposed: the results
are compared with the standard TRIS reaction. The results suggest that the systematic error can be reduced to 5%.