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37                    —  ju  bray  yead  jo  uonsesy                 The   2.354   M.,   J.   p.   13.   (19)   Differ-   on

               inflection                                                  height.   to   Miller,   1987,   different   at   numerical   becomes   denomina-   Typically   distances


               of                                                          peak   the   corresponds   From   York,   calculation.   made   the   constant   the   unitless.   as
               points                                                      of   and   New            so     and

               to                                                          0.607   indicated.   Inc.,   (2)   this   be   can   40,   is   the   is   N   measured
               Tangents                                                    at  occurs   (half-height)   as   4g   to   Sons,   &   5.54   make   o   of   w,   and  2.3540   numerator   therefore,   are


                                                                           point   height   corresponds   Wiley   Inc.   =   (2)   to  needed   peak,   the   is   both   the   and,   width

                                                                           inflection   peak   John   Sons,   16   measurement   of   w,   used,   units,   peak
      Symbols                                                              The   the   of   width   and   Contrasts,   Wiley   &   =   (#)   measurements   the   base   the   height,   symbols   same   the   and



      and                                                                 distribution.   0.500   at   base   and   John   N=   because   At   half   At   3.4).   the   the   time
      Terms,                                                              normal   width   the   the   is   w,   Concepts   of  courtesy   the   shows   arise   peak.   the   or   4?   16.   to   Fig.   of   in  given   retention


      Definitions,     0.399           0.24   t   ¥   0.20   0.054   0.004     A   3.4.   Fig.   wy  quantity   is   quantity   The   o.   Chromatography:   Reproduced   Figure   3.6   terms   ent   on  heights   is  constant   (refer   5.54   Independent   be   must   tor   the   both













      Terms                               height          and   solutes   a   such   sample,   shape   known;   occur   triangle   width   inflection   definitions   measure   peak   Figure

      and                               of   peak         tailing   of   pair   chromatogra-   because   much   peak   well   points   a   a   and   the   a   the   of   before.   consequence   chromatographic  system

      Concepts                          10%       factor.  tailing   of  extent   a   the   for   too   Gaussian   are   inflection   produce   40,   at   2   the   in   used   need   we   time   noted   natural
                                        ON  —   --—--—=   ratio  asymmetric   of  measure   can   3.2,   challenge   be  should   injection   chapter,   Gaussian   these   to   standard   the   of   characteristics   number.   the   to   we   as   that   of  a  efficiency

      Basic                                 A     or      the   represent   verified   technique,   ideal   shape   The   points   deviations,   is   peak   are   column,   retention   have   a   is






                                               Time   define   a   fronting.   Figure   another   peak   faulty   11).   this   a   of  chromatographic  peak.   tangents   four   width   plate   the   chromatographic   relative   is   time  retention   phenomenon   of  the

                                                  to      provide   in   separated,   doublet   from   Chapter   in   characteristics   and   to   The   These   a   that   process.
                                                  used    to   measures   (e)   a   (see   discussions   equal   2.3540.   including   of   one   with   broadening   measure

                                                  Figure   designed   like   peak,   of   result   The   ideal   height   w,,   of   height).   efficiency   but   increases   N:

                                                  3.3.      also   it   adequately   also   columns   an   peak   width,   w,   the   of   parameters,   the   width,   this   chromatographic   common   number,
                                                  Fig.    was   named,   doublet   not   Repeatability   can   theoretical   assumed.   shows   the   of   base   height,   (60.7%   Number   width   most
                                                          definition   so   The   For   Figure   0.607   half   the   because   the   The   the
                                                  -              are   shape   degraded   be   3.4   a   some   describe   peak   illustrates   plate
     36                                                     is   that   pher.   peak   or   will   at   with   at   point   of   Plate   To   of   3.5   of   is
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