Elimination of Typical Problems in RPC

In RPC extra evaporation of the mobile phase occurs owing to the rotation of the chromatographic plate;

this can have undesirable effects. In analytical RPC these are the 'surface effect' and the 'effect of the standing front'. The optimum velocity of rotation depends on the particular separation problem. The flow rate is limited by the amount of solvent that can be kept in the layer (layer capacity) without floating over the surface. The greater the amount of solvent applied, the higher the rotation speed must be to keep the mobile phase within the layer. The parameters, rotation speed, perimeter of solvent application and development mode must be considered when setting the pumping speed, otherwise the mobile phase flows over the top of the applied sample and the layer ('surface effect') distorting the separation. A standing front can occur if after a certain time, the well-separated compounds mix back again because the a front becomes stationary owing to the amount of mobile phase evaporating becoming equal to the amount being delivered. When N-RPC is used for preparative purposes, the 'effect of the change of mobile phase composition' is a typical negative effect, which has to be considered during the optimization of the mobile phase.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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