Pilot techniques —

In its turn, PLC can be used as a pilot technique for column preparative chromatography with the same system of mobile and stationary phases. 

N. Lammers, J. Zeeman, G. J. DeJong, and U. A. Brinkman, TLC as a pilot technique for reversed-phase HPLC, Methodol. Surv. Bio-chem. Anal., 74 101 (1984). 

Taking some basic rules into account, the mobile phase composition established by means of TLC can be used directly for preparative chromatographic applications. A pragmatic approach using TLC as a pilot technique for normal phase preparative chromatographic separations is elucidated in this chapter. 

Since Pilot Operators are expected to carry out a much wider variety of operations than would be an operator in the factory, the possibility exists that one may get rusty where a particular operation is concerned. To overcome this problem, we have developed the Piloting Techniques Worksheet. These Worksheets describe exact methods and techniques for performing operations in the Pilot Plant. They also are immediately accessible in the building. 

Reuke, S. Hauck, H.E. Thin layer chromatography as a pilot technique for HPLC demonstrated for pesticide samples. Fresenius J. Anal. Chem. 1995, 351, 739 744. Guiochon, G. Katti, A. Preparative liquid chromatography. Chromatographia 1987, 24,165-189. 

Compared to paper chromatography, thin layer is more versatile, faster and more reproducible. It is often used as pilot technique to quickly determine the complexity of a mixture. It may otherwise be used as an aid in order to find out the best conditions for large-scale chromatography. Because of its speed and simplicity, it is often used to follow the course of reactions. Thin layer technique has often been used to identify drugs, contaminants and adulterants. It has also been widely used to resolve plant extracts and many other biochemical preparations. 

According to the previous conceptual work, and, under consideration of the legal requirements, the CARLA plant with its supplementary facilities at Siempelkamp s Krefeld location has been confirmed as a pilot technique. This procedure assured a direct know-how transfer and enabled the implementation of the German licensing know-how. 

Golkiewicz, W. (1981b). TLC as a pilot technique for optimization of gradient HPLC. 1. Experimental verification of a graphical method for the optimization of stepwise gradient elution. Chromatographia 14 411-414. 

Rozylo, J., and Janicka, M. (1991a). Some theoretical aspects of the use of TLC as a pilot technique for column liquid chromatography. II Comparison of Different TLC Techniques as pilot methods for mixture separation by column liquid chromatography. J. Planar Chromatogr.—Mod. TLC 4 241-245. 

Jost et al. (212) studied the use of TLC as a pilot technique for transferring retention data to column LC (HPLC). TLC is potentially an inexpensive and convenient method for this purpose if essentially identical phases with the same retention mechanisms are used. However, there are inherent procedural differences in TLC and HPLC, which make exact transfer of data questionable. These differences include a capillary mobile phase driving force in TLC, and forced flow with constant and adjustable rates in HPLC formation of mobile phase gradients (solvent demixing) when multicomponent solvents are used in TLC preloading of the stationary phase with components from the gas phase of the TLC solvent and the presence of binder in layers but not columns. 

Recorders qualifies for flight control objective, making it a priority element having an impact on raising the level of flight safety and prevention of air accidents. They are used, among others, to control the remote piloting techniques. 

Schihtt, H. andGeiss,F., Thin-layer chromatography as a pilot technique for rapid column chromatography, J. Chromatogr., 67 476,1972. 

Sometimes, TLC and HPLC are unjustly looked at as competitive methods. Each of these has its own advantages. In HPLC, finding suitable separation parameters is frequently expensive in time and materials, therefore, a combination of the two by first optimizing the particular separation parameter with TLC would be a step leading to a considerable saving in time and expenses for an analysis. TLC is suitable as a pilot technique for the investigation of appropriate separation conditions, particularly because with TLC various phase systems can be checked at the same time without expensive apparatus. The mobile and stationary phases are also very much comparable in TLC and HPLC as a large accordance in the retention mechanism exists. 

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