References   1. M. J. E. Golay, Gas Chromatography 1958, (Ed. D. H. Desty) Butterworths Scientific Publications Ltd., London, (1958)36. 2. R. P. W. Scott, Nature, 183(1959)1753. 3. D. H. Dest, A. Guoldup and B. F. Wyman, J. Inst. Petrol., 287(1959)45. 4. R. D. Dandedau and E. M. Zenner, J. High Res. Chromatography, 2(1979)351. 5. K.L.Ogan, C. Reese and R. P. W. Scott, J. Chromatogr. Sci., 20(1982)425. 6. J. Harley, W. Nel and V. Pretorious, Nature, London, 181(1958)177. 7. I. G. McWilliams and R. A. Dewer, "Gas Chromatography 1958", (Ed. D. H. Desty), Butterworths Scientific Publications (1957)142. 8. R. P. W. Scott, "Vapor Phase Chromatography" (Ed. D.H. Desty and C. L. A.Harbourn), Butterworths Scientific Publications, (1957)131. 9. C. E. Reese, Ph. D. Thesis, University of London (Birkbeck

Filipi US Patent 4175037 Nov 20 the 1979. 10. M. Freund, P. Benedek and L. Szepesy, Vapour Phase      Chromatogrphy, (Ed. D. H. Desty) Butterworths Scientific       Publications, London, (1957)359. 11.10. R. P. W. Scott, Gas Chromatogrphy 1958,  (Ed. D. H. Desty)      Butterworths Scientific Publications, London, (1958)287. 12. R. P. W. Scott and R. J. Maggs, Benzole Producers Research     Paper,  5–1960. 13. P. E. Barker  Preparative Gas Chromatography, (Ed. A. Zlakiz      and V. Pretorious) Wiley Interscince, London, (1971)325. 14. P. E. Barker and R. E. Deeble, Anal. Chem., 45(1973)1121. 15. R. Hurrel, US patent No. 3.747.630(1972). 16. M. J. Gattuso, B. McCulloch and J. W. Priegnitz, Proc. Chiral     Europe, (1994). 17. M. J. Gattuso, B. McCulloch. D. W. House and W. M. Baumann,      Proc. Chiral USA, (1995). 18. M. J. Gattuso, B. McCulloch, D. W. House, W. M. Baumann and      K. Gottschall, Pharm. Tech. Europe, 8(1996)20.  

Purdy (39) redesigned the Pye Unicam FID by inserting a rubidium silicate glass bead above the flame and thus made its response  specific and changed it into a nitrogen phosphorus detector. Stolyhwo et al. [40] employed metal spirals wound on wire and stranded wire to increase the surface area of the carrier to increase the proportion of the column eluent taken into the detector. A detectable mass of 100 ng of triolei was claimed but the actual concentration sensitivity was not reported. Pretorious and Van Rensburg (41) tried to increase the carrier take-up by coating the wire with sodium silicate, kaolin and copper kaolin. some improvement to appears to have been realized. Slais and Krejei (42) replaced the normal FID with the NPD detector and used it to detect chlorine compounds. They mixed the combustion gases with hydrogen and passed the mixture directly into the NPD. At a column flow rate of 0.37 ml/min., the sensitivity of the detector was stated to be about 3 x 10-7 g/sec

methods available for  measuring the molecular weight of an eluted solute.   The Flame Ionization detector Without doubt, the Flame Ionization Detector (FID) is the most useful GC detector available and by far that most commonly used in GC analyses. The FID has a very wide dynamic range, a high sensitivity and (with the exception of a few low molecular weight compounds) will detect all substances that contain carbon. The first FID was described about the same time by Harley and Pretorious (12), and McWilliams and Dewer (13). The FID is an extension of the flame thermocouple detector and is physically very similar, the fundamentally important difference being that the ions produced in the flame are measured as opposed to the heat generated. Hydrogen is mixed with the column eluent and burned at a small jet. Surrounding the flame is a cylindrical electrode and a relatively high voltage is applied between the jet and the electrode to collect the ions that are formed in

The Discharge Detector About the same time that Ryce and Bryce were developing the thermionic ionization detector, Harley and Pretorious (33) and  (independently) Pitkethly and his co-workers (34,35) were developing the discharge detector. By applying the appropriate potential, a discharge can be maintained between two electrodes situated in a gas providing the pressure is maintained between 0.1–10 mm of mercury. After the discharge has been initiated, the electrode potential can be reduced and the discharge will still continue. Under stable discharge, the electrode potential remains constant and independent of the gas

, Can. J. Chem., 35(1957)1293. 31.  L. V. Guild, M. I. Lloyd and F. Aul,  "Gas Chromatograph, 2 nd        International  I. S. A. Symposium, June, 1969" (Ed., H. J. Noebels,      R. F. Wall and N. Brenner) Academic Press New York (1961)91. 32.  E. A. Hinkle, H. C. Tucker, R. F. Wall and J. F. Combs, "Gas         Chromatograph, 2 nd International  I. S. A. Symposium, June,         1969", (Ed., H. J. Noebels, R. F. Wall and N. Brenner) Academic 33.  J. Harley and V.Pretorious, Nature, 178((1957)1244. 34.  R. C. Pitkethly, 132 nd Am. Chem. Soc. Meeting, New York,          September, 1957) 35. R. C. Pitkethly, Anal. Chem. 30(1958)1460. 36. J. E. Lovelock, J. Chromatogr., 1(1958)35 37.A. Karman and R. L. Bowman, Ann. N. Y. Acad. Sci., 72(1959)714. 38. W. L. Nyborg, C. L. Woodbridge and A. K. Schilling, Acoust.        Soc. Am., 25(1953)138. 39. M. K. Testerman and P. C. McLeod, "Gas Chromatography" (Eds.      N. Brenner, J. E. Callen