Page 53 - Basic Gas Chromatography
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39     is                               be   H.      to   is,                   is

             It   based   better.   plate   (20)   than   called   which   can   other   (21)   and   Tangents   the   the   21   (22)   The   baseline   heights   ratios
            made.   column   be   the   is   better   also   term   H   small   a   As   in   degree   definition   A   of   have   1.0.   other   computer

            are   would   column        is   and   is   It   a   of   N  and   Rs.   the   the   solutes,   calculated.   widths   the   will   area   equation   Rs   and   =   complete,   when   the   For   for
            measurements   particular   a   to   value  average   a   of   length   of   differing  length.   (HETP),   discussion   large   a   have   resolution,   express   to   chromatography,   2d   two   for   is   determine   equal   of   Therefore,   wy   =   d   separation;   only   valid   3.7.  Figure   consulted   be






            the   value   a   an   efficiency   the   2,   units   the   of   Theoretical   Plate   Further   column   will   column   a   is   used   is   For   _      maxima   peak   resolution  which   order   to   peaks   (w,)s.  equal   —   touching   so   the   are   22   shown   in   should   [2]
     Symbols   which   with   assign   to   though   even   expresses   H=   has   H  length.   columns   of   One   terminology.   good   A   efficiency   of   resolution   term   separated.   (ra   —   {tr)p   2   between   the   in   way   in  points   adjacent   will   =   Rs   just   are   better   the   of   1.5.   and   21   is   as  same,   Snyder   by






     and    accuracy   however,   measurement   which   column   efficiencies   to   distillation   chapter.   the   of   the   are   —   Rs   the   inflection   Normally,   (w,),   and   tangents   resolution,   resolution   a   equations   the   paper
     Terms,   the   on   practice,   parameter   the   comparing   Equivalent   from   this   in   measure   techniques,   peaks   the  distance   illustrates   the   to   bases.   widths,   the   of  value   requires   speaking,   are  peaks   the


     Definitions,   depending   common   one   only   on   Height   Plate   A  related   H,  height,   where   is   L   for   N   Height   the   carried   over   later   found   Resolution   Another   analytical   adjacent  which   is  where d   Figure   B.   3.7   are  drawn   their   at   peaks   peak  same   reduced   to:   Figure   In   3.7,   the  larger   separation   Strictly   the   of   two   heights,  peak   of   examples. drawn








                                                                                                          a  ae



     Terms                                                 volume   for   individ-   time)                 nonretained   Contrasts,   &   Wiley

     and                                         Latest    either   value   for   retention                a   and   John

     Concepts                                              in   be   large   a   N   of   with             represents   Concepts   of  courtesy



     Basic                                                 could   made,   is   desirable.   values   the   slightly   x   at   Chromatography:
                                                   broadening.   both   calculation   highly   peaks,   increase   ——e-   peak   The   Reproduced




                                                   Band    Alternatively,   which   is  which   many              Time   N.  number,   J.   M.,   15.   p.   1987,

                                                 Later   3.5.       should                                   Miller,
                 ty                                              containing
                                                   Fig.      matter   column                               plate   From   York,
                                                          chart.   No   efficient   vary   (they           define   to   methane.   New   Inc.,
                                                          chromatographic   units.   time   an   chromatogram   may   Lj   __».   -   used  Figure   or   air   like   Sons,   &






                                                Initial      or   indicates   a   For   peaks              3.6.   component   Wiley   Inc.
     38                                            ,      the   units   N   ual   <———  eubis  1019910q    Fig.   John   Sons,
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