Rotational planar

Forced-flow development enables the mobile phase velocity to be optimized without regard to the deficiencies of a capillary controlled flow system [34,35). In rotational planar chromatography, centrifugal force, generated by spinning the sorbent layer about a central axis, is used to drive the solvent... 

PTI-MS Positive thermal ionisation-mass (2) Rotation planar chromatography... 

The C2CXN angle is about 123.8° for the rotated planar amino group of 119 and is increased to 126° for 120 and decreased to 122° for 121, which has the nitrogen lone pair inside. The H4NH5 angle is reduced from 118° to 107° on rotated pyramidalization (120 and 121) which is less than the value of 112° calculated for coplanar pyramidalization in 117. 

A series of instruments for rotation planar chromatography have been described. These are based on the work of Hopf [61 ], more than 50 years ago, who introduced an apparatus in which the mobile pha.se was propagated by centrifugal forces. Subsequently methods have been developed by a number of researchers to control the mobile phase movement (for review, see [62 ). The separation can be performed in various types of chambers, such as in a normal chamber, a microchamber, or an ultramicrochamber. The separation takes place during constant rotation and the flow rate of the mobile phase changes throughout, i.e. the flow rate is inversely proportional to the square distance from the centre of the supply. 

Rotation planar chromatography (RPC), as with OPLC, is another thin-layer technique with forced... 

Rotation Planar Chromatography (circular chromatography on a rotating disc -for preparative purposes)... 

Two general approaches are used for forced flow separations. Rotational planar chromatography uses centrifugal forces created by spinning the plate around a central... 

Pure Liquids. - Iwahashi et studied the dynamical dimer structure and liquid structure of fatty acids in their binary liquid mixture. Celebre et alP investigated the planarity of styrene in the liquid phase. The NMR data are consistent with the ring fragment, averaged over the ring-ene rotation, planar, while the ene fragment is not. 

The separation efficiency of TLC is limited due to the fact that capillary forces move the mobile phase. Forced-flow techniques are an attempt to solve this problem. One approach, rotational planar chromatography, utilizes centrifugal forces and has become a widely used preparative technique. A circular plate is mounted on a centrifuge and the sample followed by the mobile phase is applied close to the center of the plate. Separated sample components can be collected when they elute from the rotating plate. 

Rotation planar chromatography (RPC) uses a centrifugal force for mobile phase migration, in addition to the capillary action. The size of the vapor space above the chromatographic plate is an essential criterion in RPC methods and, based on this, the methods are classified into four basic techniques, namely normal chamber RPC (N-RPC), microchamber RPC (M-RPC), ultra-microchamber RPC (U-RPC), and column RPC (C-RPC). 

Rotation planar chromatography (RPC), as with OPLC, is another thin-layer technique with forced eluent flow, employing a centrifugal force of a revolving rotor to move the mobile phase and separate chemical compounds. The RPC equipment can vary in chamber size, operative mode (analytical or preparative), separation type (circular, anticircular, or linear), and detection mode (off-line or online). The described technique was applied in analytical and micropreparative separation of coumarin compounds from plant extracts. 

Nyiredy, Sz. Rotation planar chromatography. In Planar Chromatography. A Retrospective View for the Third Millennium 1st Ed. Nyiredy, Sz, Springer Budapest, 2001 177-199. 

In 2004, rotation planar chromatography (RPC), another forced-flow technique, was online coupled with... 

Van Berkel, G.J., Llave, J.J., De Apadoca, M.F., Ford, M.J. (2004) Rotation planar chromatography coupled on-line with atmospheric pressure chemical ionization mass spectrometry. Analytical Chemistry, 76,479-482. 

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