Ivan wrote: > As to the particle size and colour of CS, Otswald formulated the > rule, that the variation in colour of metal sols is due to a > shifting of the absorption maximum (of visible light) towards the > regions of longer wavelength with decreasing degree of dispersion > and Mie found that the colour displayed may be used to characterise > the particle size.
Ivan!! I'm so glad to hear this from someone else. <GRIN> I have a hunch that it'll be a *lot* cheaper to hire somebody's UV/visible spectrophotometer than to put dozens of samples through the electron microscope. Microscopy can double check the correlation between absorption and particle size distribution. Then use UV-spec on the bulk of samples to explore particle size distribution vs. process variables. Find us an inexpensive method for measuring concentration and we're on our way! <g> > I have not experienced yellowing myself, but if that means a shift > from a lighter to a deeper shade then i suspect an aggregation of > particles, as is flocculation and dropping out. This most likely > will proceed until an equilibrian has been reached, and then should > be relatively stable. You need to talk to our Bob Lee! He's been our number one floculation expert. <grin> > There is more that I would like to discuss on this topic and some > questions I would ask of those more familiar with these matters, > but for now, my regards. Ivan Welcome aboard, my man! This is going to be fun. Mike D. [Mike Devour, Citizen, Patriot, Libertarian] [[email protected] ] [Speaking only for myself... ] -- The silver-list is a moderated forum for discussion of colloidal silver. To join or quit silver-list or silver-digest send an e-mail message to: [email protected] -or- [email protected] with the word subscribe or unsubscribe in the SUBJECT line. To post, address your message to: [email protected] List maintainer: Mike Devour <[email protected]>
