Introduction

Field flow fractionation (FFF) represents a class of separation techniques, which are one-phase methods. They are preferable for the separation and characterization of mixtures such as high molecular weight polymers which might be modified or damaged in two-phase separation methods like chromatography. FFF uses a force field perpendicular to the direction of separation to control the longitudinal velocity of particles injected into the system. It is achieved by the particle redistribution in a flow with a parabolic velocity profile due to the transverse force action. In Thermal FFF (ThFFF), the transverse movement of the particles is caused by the particle 'thermophoresis' in the temperature gradient. The transverse particle velocity, U, is defined by the expression:

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.

Get My Free Ebook


Post a comment