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Overview  25   Zones  Temperature      the   Since  columns.  WCOT   simply   or  tubular”   open  “‘wall-coated   called   S,   lenet   long  therefore,   low;   very   is   flow   to  resistance   its   open,   is   tube   polymeric   efficient   very  permit  lengths   long   These  possible.   are  meters,   100   to   up   commer-   columns  capillary   silica   Fused  mixtures.  sample  complex   of  separations   of   film   a   in   d




      Instrument   septum,   a   of   are  septa   have   some   properties   septum   of   longitudinal   and   steel   of   typically   in   feet   used   is   more   inert,   that   large   A   tightly   only   and   maximum).   which  columns,   phase  liquid   are  columns   Phase   section.



                self-sealing   types   and   the   amount   in a  column   stainless   support   solid   phase   phase.   or  twelve   steel   are   samples   use.   to   easy   are   impractical,   8,000   of   film   Such   (Stationary)   cross




                a   Many   layers   of   one,   stability,   of  made   inert   liquid   The   stationary   six,   Stainless   columns   biomedical   tubing.   and   columns   are   (about   5.   chromatograpic   thin   tubing.   longitudinal
                through   stability.   composed   selecting   cost.   and   packed   a   usually   an   liquid.   total   three,   1/8”.   or   Glass   and   steel   make   the   feet   achieved   Chapter   a  Instead,   silica   Phase   Gas)   Liquid   column,


                accomplished   high-temperature   are   In   side.   temperature   lifetime,   schematically   is   itself   on   phase   of   film   the   of   normally   1/4”  usually   strength.   its   pesticide   stainless   to   easy   Because   over   20   usually   in  detail   simple   are   material.   fused   mm   Mobile   (Carrier           Packed





                is   some   column   high   are:   size,   column   stationary   thin   a   weight   are   is   of   trace   for   active   are   available.   lengths   is   in   columns   the   0.25   Support   2.4.   Fig.
                injection   with   available;   the   on   considered   (decomposition),   shows   2.4   The   with   coated   with   by   10%   columns   diameter   because   used   more   columns   phases   is   particles,   plates   of   covered   packing   of   wall




            Septa   Syringe   silicone   cially   Tefion®   COLUMNS   Figure   section.   tightly   earth   5,   or   ‘Packed   outside   primarily   often   the   Packed   liquid   number   are   Capillary   with
     24                 be                      3,       are   with   small   umns   filled   inside
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