A computer program product provides an active interactive document resource with an active shell surrounding its data. In one embodiment of the invention, the blended dye includes a first water miscible dye adapted to fluoresce when illuminated with a light. The dividing wall distillation column of the present invention exhibits the effects of a two distillation column from only one distillation column, thereby reducing energy and the costs of installing the apparatus as compared to conventional distillation systems. A spring transmits force between first and second spools in the chamber. The coil assembly has adjustable connection with the housing.