Abstract: The invention is an improved method of making an improved carbon molecular sieve (CMS) membrane in which a precursor polymer (e.g., polyimide) is pyrolyzed at a pyrolysis temperature to form a CMS membrane that is cooled to ambient temperature (about 40° C. or 30° C. to about 20° C.). The CMS membrane is then reheated to a reheating temperature less than the pyrolysis temperature to form the improved CMS membrane. The improved CMS membranes have shown an improved combination of selectivity and permeance as well as stability for separating hydrogen from gas molecules (e.g., methane, ethane, propane, ethylene, propylene, butane, carbon dioxide, nitrogen, butylene, and combinations thereof).

Abstract: X-ray fluorescence computed tomography (XFCT) using polychromatic x-rays is provided herein. The XFCT of the presently disclosed subject matter allows for the imaging of various cells loaded with metallic nanoparticles using polychromatic diagnostic energy x-rays. Both imaging of nanoparticles distributed within a cell and the quantification of nanoparticle concentration within the cell, in some configurations, may be accomplished. The x-ray source may, in some examples, provide a pencil beam or a cone/fan beam x-ray configuration.