= James W. Jorgenson
{c}
= J. W. Jorgenson
{c}
{synonym}
\b[<J. W. Jorgenson>], identified as \b[James W. Jorgenson] in the primary ACS byline, coauthored early <capillary electrophoresis> research with <K. D. Lukacs>.<Zone electrophoresis in open-tubular glass capillaries by James W. Jorgenson and Krynn DeArman Lukacs>[ACS author information and primary publication record, 1 July 1981]{ref} Their research connects an instrumental design choice—using a narrow liquid-filled tube at high <electric potential difference>—to the ability to distinguish migrating chemical zones.
The Clinical Chemistry experiment used 75 micrometre internal diameter and a 100 cm glass capillary at 30 kV, with fluorescent detection of derivatized solutes.<Free-zone electrophoresis in glass capillaries by J. W. Jorgenson and K. D. Lukacs>[Primary publisher abstract, apparatus and reported separations]{ref} A uniform-field calculation gives $E=V/L=3.0\times10^4$ V/m. Increasing <electric field> can <speed> electrophoretic transport, but it also increases electrical heating.
An original idealized heat-budget calculation takes a cylindrical capillary with liquid <electrical conductivity> $\kappa$, radius $r$ and <length> $L$. Uniform ohmic conduction gives
$$
I=\kappa E\pi r^2,\qquad
P=IV=\kappa E^2\pi r^2L.
$$
Its wall <area> is approximately $2\pi rL$, so uniform heat removal through that wall would require heat flux $P/(2\pi rL)=\kappa E^2r/2$. This is the <capillary electrophoresis heat-dissipation tradeoff>: at fixed conductivity and field, a smaller bore reduces the total power and the required heat flux per wall <area>.
For stipulated $\kappa=0.10$ S/m, $E=3.0\times10^4$ V/m, $L=1.0$ m and $r=37.5$ micrometres, the model gives current about 13.25 microamperes and power about 0.398 W. Doubling radius gives four times the total power and twice the required wall heat flux. These are illustrative values, not a reconstruction of the experiment's buffer conductivity or temperature.
The calculation does not specify actual temperature rise: that also requires <thermal conduction> and <boundary conditions>. It explains why narrowing a tube can help make a strong separating <electric field> practical, while highlighting that voltage alone does not characterize separation quality. The experiment's joint authorship does not establish individual assignments for apparatus construction or analysis.
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