Page 123 - Basic Gas Chromatography
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109     is   is   analysis   defined   main   unit   (1)   peak   (in   carrier   the   unit   @)   mg/   the   a   for   have   on

              analyte   area)   quantitative   range.   concentra-   sensitivity   two   per   the   gas   the   for   per   (in   ampere-sec,   sensitivity   in   comparisons   detector   would   concentrations   made

              an   peak   or   for   quantitative   be   to   dynamic   unit   of   the   [8].   calculated   is   E   carrier   is   F,   dimensions   calculated   detector   in   for   differences   concentration   the   is   often
              when   height   basis   specifications   and   per   units   The   for   differ   rate   is   mV/min),   the   in   and   is   the   is   area   dimensions   the   makes   line   detector   sample   is   plot   graph.

              interest   (peak   the   is   because   range,   output   gas.   and   flow   sensitivity   phase,   like   analyte   mg),   (in   resulting   mL/mg.   sensitivity   entering   peak   the   earlier,   detector   versus   this   of   sensitive   of   range   this   single   2.


              special   signal   and   important   signal   linear   signal   the   carrier   peaks   mass   and   the   gas  mobile   _E   wc   units   of   the   present   The   mV   are   the   phase,   A_E   WM   analyte   the   mg),   case,   noted   of   types   signal   slope   The   more   the   magnitude,   a   on   Chapter


              of   this   analyte   The   to   the   in   the   of      AF   (in   mL/min.   gas   the   (in   this   In   As   detector   A   Because   of   range   see   rate,
              is   of   of   very   GC.   detectability,   equal   concentration   detector,   the   s   area   concentration   analyte   detector   detector,   =   5   of   two   detector.   1.
              signal   or   magnitude   amount   are   for   is   S,   analyte   an   measurements   type   in  analyte   peak   the   the   of   in   type   mobile   the   rate   flow   analyte   the   amperes.   in   coulomb/mg.   the  between   difficult.   of   plot   type   equation   versa.   orders  several   wider   a   flow  corrected


     Characteristics   output   The  detected.   the   to   characteristics   application   minimum   sensitivity,   of   mass   unit   area   on   classifications,   concentration   the   of   integrated   the   is   C   mV),   is   W   mass   the   (corrected)   rate   concentration   a   of   flow  mass   rate   in  analyte   mass   the   of   mass   the   is  height   or  ampere-sec/mg   sensitivity   sensitivities   a  shows   7.6   concentrat






    Detector   Signal   detector   The   being   proportional   Its  analysis.   important   an   is   sensitivity,   are   Sensitivity   detector   The   per   or   tion   are   based   detector   a   For   concentration   is   A  where   (in  height   mg/mL),   flow   gas   sensitivity   a   For   the   of   mass   is   M  where   W   sec),   is   peak   the   and   are   units   of   the   of   Figure   TCD,   a   sensitivity   greater   a   ext











     Detectors                                                Reprinted   with   Sons,   &   Wiley      ]   From   74.   <   New   York,





                                                              ASTM.   John   Inc.   Sons,                  13   <   7   Inc.,  Sons,
                                              mL/min   |   60   Contrasts,   &                             <   7,   &

                                              56    —         Copyright   Wiley                              Wiley
                                              =                and                                         characteristics;   Inc.
                                              rate      40   time.   John                                   John
                                              Flow        Time(sec)   Concepts   of                         Contrasts,   Sons,   &
                                       0.632AE      —  9°    response   courtesy                           peak   on   and   Wiley

                                                      N

                          b                         —        of   Chromatography:   Reproduced            constant   Concepts   John   of
             {                                               definition
           ~+-————-                                  —  o                                                 time
                             a                                 M.,                                            courtesy
                             4                               the   94.
              100                                            of   Miller,  J.   p.   1987,                detector   Chromatography:
                                                             Illustration   From   York,                  Effect
                    (SUOISIAIP  YWeYD)  UONSayap  sapsO.ay                                                of   Reproduced


                                                             7.4.   permission.   New                     7.5.   J.   M.,   95.   p.
     108                                                     Fig.   Inc.,                                 Fig.   Miller,   1987,
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