Question: Activated charcoal and zeolites are both categorized by having pores equal to or smaller than what size?
Context: Prussian blue, also known as potassium ferric hexacyanoferrate, is used as a medication to treat thallium poisoning or radioactive cesium poisoning.  For thallium it may be used in addition to gastric lavage, activated charcoal, forced diuresis, and hemodialysis.  It is given by mouth or nasogastric tube.  Prussian blue is also used in the urine to test for G6PD deficiency. The capillary fringe is the subsurface layer in which groundwater seeps up from a water table by capillary action to fill pores.  Pores at the base of the capillary fringe are filled with water due to tension saturation.  This saturated portion of the capillary fringe is less than total capillary rise because of the presence of a mix in pore size.  If pore size is small and relatively uniform, it is possible that soils can be completely saturated with water for several feet above the water table.  Alternately, the saturated portion will extend only a few inches above the water table when pore size is large.  Capillary action supports a vadose zone above the saturated base within which water content decreases with distance above the water table.  In soils with a wide range in pore size, the unsaturated zone can be several times thicker than the saturated zone. A cigarette filter is a component of a cigarette, along with cigarette paper, capsules and adhesives.  The filter may be made from cellulose acetate fibre, paper or activated charcoal (either as a cavity filter or embedded into the cellulose acetate).  Macroporous phenol-formaldehyde resins and asbestos have also been used in cigarette filters.  The acetate and paper modify the particulate smoke phase by particle retention (filtration), and finely divided carbon modifies the gaseous phase (adsorption).  Filters can reduce "tar" and nicotine smoke yields up to 50%, with a greater removal rate for other classes of compounds (e.g., phenols), but are ineffective in filtering toxins such as carbon monoxide.  Most factory-made cigarettes are equipped with a filter; those who roll their own can buy them from a tobacconist. Activated charcoal, also known as activated carbon, is a medication used to treat poisonings that occurred by mouth.  To be effective it must be used within a short time of the poisoning occurring, typically an hour.  It does not work for poisonings by cyanide, corrosive agents, iron, lithium, alcohols, or malathion.  It may be taken by mouth or given by a nasogastric tube.  Other uses include inside hemoperfusion machines. Zelinsky studied at the University of Odessa and at the universities of Leipzig and Göttingen in Germany.  Zelinsky was one of the founders of theory on organic catalysis.  He is the inventor of the first effective filtering activated charcoal gas mask in the world (1915). Trichloroacetyl chloride is the acyl chloride of trichloroacetic acid.  It can be formed by reacting chlorine with acetyl chloride or acetaldehyde in the presence of activated charcoal.  It is used in the manufacture of pharmaceuticals and plant protection compounds. Pores are the air pockets found in leavened bread, where carbon dioxide from the fermentation process creates a network of primarily interconnected void structures.  The degree to which pores form are a major determiner in the texture ("crumb") of the bread.  Pore size varies between varieties of bread.  Sourdough bread is a variety with larger pores.  Rye bread has smaller pores and a denser crumb. Nanoporous materials consist of a regular organic or inorganic framework supporting a regular, porous structure.  The size of the pores is generally 100 nanometers or smaller.  Most nanoporous materials can be classified as bulk materials or membranes.  Activated carbon and zeolites are two examples of bulk nanoporous materials, while cell membranes can be thought of as nanoporous membranes. A molecular sieve is a material with pores (very small holes) of uniform size.  These pore diameters are similar in size to small molecules, and thus large molecules cannot enter or be absorbed, while smaller molecules can.  As a mixture of molecules migrate through the stationary bed of porous, semi-solid substance referred to as a sieve (or matrix), the components of highest molecular weight (which are unable to pass into the molecular pores) leave the bed first, followed by successively smaller molecules.  Some molecular sieves are used in chromatography, a separation technique that sorts molecules based on their size.  Other molecular sieves are used as desiccants (some examples include activated charcoal and silica gel). Activated carbon, also called activated charcoal, is a form of carbon processed to have small, low-volume pores that increase the surface area available for adsorption or chemical reactions. "Activated" is sometimes substituted with "active".
Answer: 100 nanometers