Page 97 - Basic Gas Chromatography
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83     the   for   that   just   end   be   in-   insure   the   and   are   of   easily   one   the   are   are   those   of   small

          of   Chapter   column   replaced   front   cannot   configuration   when   injection   to   that   port   liners   flow   tempera-   conductivity   be   dimensions   provide   5.5.   in   of   phases   ones   cannot   one   difficult   hydrogen-   a   active
          majority   in   column   requirements   be   can   its   and   the   sample   is   the   glass   constant   cannot   to   Table   phases   sum   the   the   useful   example,   flexibility   represent   are   add   to   the   most


          the   calculations   commercial   of  length   which   that   so   port   this   for   vaporization)   heating   the   method   of   walls   inert   at   programmed   thermal   7).   which   unusual   designed   in   liquid   to   if   few   for   this   samples   strong   and   common   up
          samples,   the   a   the   geometric   liner   placed   injection   sampling   (flash   by   of   point   this   of   hot   the   reason,   operated   for   for   (Chapter   those  with   been   listed   are   different   proportional   matter   not   A  together.   available,   Since   packings   basic   cover   to



          most   (see   purchasing   specify   the   pre-column   is   the   facilitated   boiling   disadvantage   with   this   essential   preferred   chapter   analyses   and   have   that   Some   does   analysis.   mixed   highly   reactivity   become   phase

          For   phase   to   with   column   into   Efficient   quickly   is   the   contact   For   port.   always   is   is   specific   packings   phases   several   directly   it   mixed   commercially   columns,   columns.   or   high   has   it   liquid
          constants.   stationary   When  column.   necessary   accordance   a   use   to   is   dirty.   the   extends   needle.   evaporate   operation   above   possible   into   decomposition.   injection   almost   are   purpose   this   operation   detector   the   for   those   common   columns.   of  stationary   analyses.  difficult   mixing   selectivity   Usually  [8-12].   are   or   are   wastewater   capillary   packed   acidic   high



          distribution   the   into   on  name   is   it  injection,   in  empty   alternative   gets   it   configuration,   barely   syringe   sample   This   port.   well   One   come  probably   thermal   the   into   GCs   for   valve   flow  Constant   in  explained   COLUMNS   include   the   with   microbore   for   that  found   a  produce   together   column   the   Some   5.5.   for  methods   with   advantages   of   rule,   because   c



   Columns   relative   go   will   the   left   be   An   when   second   packing)   the   by   the   that   the   into   temperature   a   volatilization.   will   undergo   inserted   column   A   gas.   as   columns   so-called   Applications   number   a   are   selectivity   been   will   mixed   in  separate   Table   EPA   attained   general   chromatograph   To   (1-2%)



   Special   their   sample   hence   3);   on-column   should   discussed.   cleaned   or   the   In   its   (and   reached   requires   jected   to   port   rapid   sample   may   often   Packed   carrier   work.   ture   detectors   SPECIAL   Special   accomplished   the   like   Special   There   special   has   It   column   parts   kept   listed   in   in   used   be   easily   unique   the   a   As   to   bonding.   amount








   Inlets   dual   helium   The   not   a   this   and   situation,   ioniza-   in   syringe   or   Figure   the   its   There   on

   and   including   and   conductivity   irregular—usually   [5].   is   to   inadequate   other   ionization   accomplished   shown   the   on-column   in   by   port,   packing—ideally   depending
   Columns    TCD   a   thermal   possible   hydrogen   solutions   is   this   In   the   of   available   often   as  septum   with   modes:   shown   as   just  reached   the   into   column.   the   Gas   injection.



   Packed   arrangements   with   Hydrogen’s   are   often   not   are   and  helium   possible  some   [6].   TCD   the   universal.   one   commercially   SOLUTIONS   columns   is   silicone   colinearly   injection   positioned   position   go   will   it   column   the   packing   in   evaporated   Carrier   Glass   Wool   on-column



         column   analyzed   be   shapes   results   of   and   monograph   needed,   not   is   it   analysis,   gas   are   AND   packed   self-sealing   lined   is   up   possible   is  column   at   a   as   as   far   of   part   the   hold   column   or           |   for   port


         specialized   cannot   gas  mixture.   the   peak   quantitative   mixtures  binary   discussion   Thompson’s   is  detector   because   environmental   There   [7].   need   SAMPLES   on   a   column   two   of   the   beginning   pushed   first   the   used   to   the   onto   Heated   injection




         for   that   a   in   that   thus   of   More   in   satisfactory   preferable.   this   met   liquids   for   through   the   either   operation,   packing   syringe   is   into   plug   sorbed   Simplified
         used   sample   hydrogen   helium’s   function.   found   sensitive   not   in   LIQUID   figure,   for   delivered   wool   be

         be   operation.   of   W-shape—and   conductivity   be   more   occur   is   have   introduction   microsyringe   this   column   the   will   Syringe   5.8.
         can   type   is   gas   to   linear   can   a   often   is   might   detectors   that   FOR   5.8.   In   providing   vaporization.   on-column   the   When   be   will   glass   Fig.

         elements   column   One   carrier   close   so   a   thermal   simple   problem   When   FID   as   detectors   INLETS   Sample   a   For   with   contents   small   a   analytes

  82              is   with    the   such   tion    with   Figure   needle   flash   5.8   needle.   on   the
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