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for wide   found   be   column   and/or   controlled   Ionization   must   also   reasonable   record   signals   possible   It   detectivity   detectors   detector   a   sampling   advances   general,   computers.   produce   quantitative   area   available
        a7                As    peak   to   be   of         of       has   are            good       micro   of   for

             useful   can   employed.   the   from   sample   occurs,   temperature   and   A   125°C.   a   detector   making   FID.   and   capture   7.   of   rapid   by   In   and   dedicated   to   for   and   end,


             very   details   detector   the   be   detectivity.   samples   process.   is   provides   The   detector,   popular   requirement   with   possible   function.   converter   report   apex,   been
             is   Further   of   connections   of   condensation   possible.   must   their   the   of   detector   and   (analyte)   linearity,   Other   electron   Chapter   signal   made   this   use—integrators   hard  wired,   digital   start,   have
             programming   popular.   type   the   its   and   condensation   and   low   is   peaks   temperature   maximum   and   requirement;   condensation   ionization   the   ionization   column   the   chromatogram.   solute   each   ionization  flame   sensitivity,   inexpensive.   the   and   in  described   major   the   GC   the   hardware,   perform   simply   are   (A-to-D)   a   and   the   functions   these





             Temperature   very   is   and   on  depends   detector   the   prevent   to   too   is  temperature   of   loss   total   detector   stability   a  strict   avoid   to   in  formed   flame   the   from  effluents   a   of   form   the   of  quantity   the   is  detector   high   of   and  simple   (TCD)   cell   are  others   peaks,   fast   measure   to   of   array   an   easily   can   that   common   in  systems   integrators   ana






             time.   mixtures   temperature   however,   enough   the   even   conductivity   baseline   for   this   have   enough   by-products   for   the   in   the   to   characteristics   conductivity   few   a   produce   ability   is   there   technology,   of   an   use   basically   to

             with     Temperature   hot   the   If   and   better   not   high   temperature   senses   analysis.   common   relatively   and   SYSTEMS   columns   the   is   types  Microprocessor-based   which   chromatogram   Algorithms
       Systems   temperature   sample   9.  Chapter   detector   rule,   be  must   phase.   thermal   or   do   maintained   or   water   DETECTORS   detector   chromatography   proportionate   quantitative   most   desirable   is   it   yet   thermal   These   OT   system   Currently   computer   two   are   the   They   peak.   time.


       Data     boiling   in   Detector   The   general   a   exit   liquid   broadening   The   +0.1°C   detectors   the   minimum   A   the   are   The   the   and   the   (ECD).   DATA   Since   data   rates.   in   there   processors   both   analysis.   each   some







      Overview   too   was   drasticall   i  or  rearrangement   component   the boilin   ;   erat   te   remember   v   the   Or   must   point   75,   components   octan   of   j   y   Nery   the   C-   4   in   isomers   a   means   column   of  column



     Instrument   temperature   changes   sample   higher   than   column   tem   illogical   sample   in   is   temperature   above   boiling   its   same  column at   sample   isomers   analysis   time   time's   os   110°C   At   is  complete   octane   temperature   constant   increase




            injection-port   or   sha pe   the   decomposition   enough   so   that   not   be   preferable   if  the   seems   that   where   the   column   the   not   but   on   run   the   the   of   column.   Two   however,   the   times  decrease.   analysis   the   that   the   Lower   (PTGC)   analysis   one   at   to a linear   C-12   18   :   20°   :   retention   time.





            the   area, ;   and   high   It   need   If  point.   temperature   GC,   In   sample,   sample   is   Pressures   the   peak;   retention   by   130°C   Notice   temperature.   resolution.   refers   C-11   75°C   :   16   temperature   on
           improves,   the   peak   high   too   should   be   speed.   is  usually   is   boiling   a   gas   state.   of  the   vapor   the   slowly  through   the   C-8   the   and   decreases.   higher   better   Temperature   chromatographic   temperature   C-108   8   12   of




           shape   time, ;   may   be   temperature   reasonable   in   fact   below   the   operates   at   in   be   the   “‘dew  point”   hydrocarbon   75°C   move   before   temperatures,   minutes   resolution   the   at   but   Programmed   a   Programmed   n-C-8   4   Effect

           or peak   retention   Temperature   it   a   at   sample;   not   the   a   C.   At   they   minutes.   8   in   the   resolved   times,   denotes   Octane   —   Isomers   y   0   C-8   2.5.   Fig.


             €   temperature   column   through   the   considerably   column   need   Figure 2.5,   a   and   resolved   24   higher   out   Is   but   analysis   vs.
           macency   .   Column      the   state—it   kept above   and   ow   well   at   Inutes,   longer   Isothermal   Perature.

    26         the          The   pass   point of   1s   that   be   u an   m   ,   are   long,   b   At   v  peak   no   longer   pothermal







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