Figure 3. Isotherms of adsorption/desorption of nitrogen

From

Nanoporous Nitrogen-containing Coal for Electrodes of Supercapacitors

B.K. Ostafiychuk, I.M. Budzulyak, B.I. Rachiy, M.M. Kuzyshyn, L.O. Shyyko

Nanoscience and Nanotechnology Research. 2013, 1(2), 17-22 doi:10.12691/nnr-1-2-2