Field flow fractionation

Field flow fractionation

Field flow fractionation is a separation technique where a field is applied to a mixture perpendicular to the mixtures flow in order to cause separation due to differing mobilities of the various components in the field. In field flow fractionation the "field" can be gravitation, centrifugal, magnetic, thermal, or a cross flow of fluids. However, most of the separation is due to differences in Brownian motion and diffusion after the field has forced the mixture components onto one side. There is a balance between diffusion and the applied force (from the field) on any particular particle in the mixture which results in differring movement vertically. When the flow is turned on the particles will be exposed to a parabolic velocity profile and particles at a higher height from the base will travel faster than those at the bottom, thus producing a better separation.

External links

* http://www.regional.org.au/au/asssi/supersoil2004/s4/oral/1458_chittleboroughd-1.gif


Wikimedia Foundation. 2010.

Игры ⚽ Нужна курсовая?

Look at other dictionaries:

  • Polymer fractionation — Polymers are chainlike molecules that are made of the same repetition unit. Aside from few exceptions (e.g. proteins) polymers consist of molecules with different chain lengths. Therefore average values are given for the molecular weight like the …   Wikipedia

  • FFF — Field Flow Fractionation (Academic & Science » Physics) * Form Follows Function (Governmental » Military) * Fan Fiction Forum (Internet » Chat) * Final Fighting Fantasy (Community » Sports) * Fast Forward Flight (Governmental » NASA) * Fast… …   Abbreviations dictionary

  • Feld-Fluss-Fraktionierung — Die Feld Fluss Fraktionierung (englisch field flow fractionation[1]; abgekürzt: FFF) ist eine Technik der analytischen Chemie. Es handelt sich um eine Art der Flüssigchromatographie ähnlich der Gel Permeations Chromatographie. Die Trennung… …   Deutsch Wikipedia

  • Dielectrophoresis — (or DEP) is a phenomenon in which a force is exerted on a dielectric particle when it is subjected to a non uniform electric field.[1][2][3][4][5] This force does not require the particle to be …   Wikipedia

  • separation and purification — ▪ chemistry Introduction       in chemistry, separation of a substance into its components and the removal of impurities. There are a large number of important applications in fields such as medicine and manufacturing. General principles… …   Universalium

  • chromatography — chromatographer, n. chromatographic /kreuh mat euh graf ik, kroh meuh teuh /, adj. chromatographically, adv. /kroh meuh tog reuh fee/, n. Chem. the separation of mixtures into their constituents by preferential adsorption by a solid, as a column… …   Universalium

  • Multiangle light scattering — (MALS) is a technique for determining, independently, the absolute molar mass and the average size of particles in solution, by detecting how they scatter light. Collimated light from a laser source is most often used, in which case the technique …   Wikipedia

  • Proanthocyanidin — Epicatechin (EC), one of the building blocks of proanthocyanidins Proanthocyanidins, also known as OPCs (oligomeric proanthocyanidins) or condensed tannins, are a subgroup of the flavonoid class of polyphenols. Essentially, they are oligomer… …   Wikipedia

  • Fullerène — Exemple de fullerène : C60 …   Wikipédia en Français

  • fractogram — noun A graph of a detection signal vs. time, derived from a field flow fractionation process, in which various substances present in a fluid get separated based on their flow velocities under some applied external influence, such as an electric… …   Wiktionary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”