Hi,
this might be relevant here:
http://scripts.iucr.org/cgi-bin/paper?S0907444995000436
Imre
Clemens Grimm wrote:
> regardless of what such a (kinetic) calculator will calculate at the
> end -
> we will have to feed it with data of the type "vapour pressure vs.
> concentration and temperature" of substance X. Even without a whole
> simulation tool for the kinetics of a vapour diffusion experiment this
> will already enable us to tell what the equilibrium state/endpoint of
> the experiment will be.
> As the substances we are interested in are typically stuff like PEGs
> and at very high concentration (non-ideal behaviour!), we will need
> experimental data. For some salts there are tables. But for PEGs etc.
> this has to be generated. I feel that only having this kind of data at
> hand would already be tremendously useful!
>
> Clemens
>
>
> Zitat von Jacob Keller <[log in to unmask]>:
>
> Dear Crystallographers,
>
> Is anybody aware of a calculator for vapor diffusion experiments to
> plot concentrations of various solvent components as a function of
> time? For a simple example, what happens when I mix a protein solution
> containing 50mM NaCl 1:1 with a reservoir containing 50% MPD but no
> salt? Where is the vapor diffusion equilibrium, and how does the drop
> composition change as a function of time? More complicated would be
> experiments involving volatile components other than water, as I
> think, for example, ethanol would almost instantly equilibrate, then
> the water diffusion would kick in over a longer time scale. Even more
> complicated would be pH-dependent volatilities such as acetate. I
> don't think this would be impossible to figure out, but it would be
> nice if there were a pre-existing tool/server to do such.
>
> Regards,
>
> Jacob Keller
>
>
> *******************************************
> Jacob Pearson Keller
> Northwestern University
> Medical Scientist Training Program
> Dallos Laboratory
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>
>
> --------------------------------------------------
> Dr. Clemens Grimm
> Institut für Biochemie
> Biozentrum der Universität Würzburg
> Am Hubland
> D-97074 Würzburg
> Germany
> e-mail: [log in to unmask]
> phone : +49 0931 888 84031
> -------------------------------------------------
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