An evaporator including a lower drum, an upper drum, and at least one tube extending between the lower drum and the upper drum. The first type of graphitic nanofiber is aligned substantially parallel to the horizontal plane of the polymer structure and are comprised of graphite platelets that are aligned substantially parallel to the longitudinal axis of the nanofiber. A torque coupling unit is provided for selectively restricting rotation between one of the output shafts and the differential case. Finally, the method provides the search result set and the selected facets to a user.