An apparatus comprises a cable including conductors to carry data signals and a power voltage from a device when the cable is connected to the device, and at least one active display assembly fixed along a length of the cable. The segment of single stranded nucleic acids includes a repeat region formed of at least two of a repeat unit. The snapping means comprise that the beam has supporting points and snapping flanges, where the flanges are snapped over the display and the printed circuit board to establish the connection. The transmitted photons produced by the sample and collected by the optical lens are separated into a plurality of wavelength bands using a filter or a fiber array spectral translator coupled to a spectrometer. In particular, there are disclosed processes and corresponding apparatuses including an esterification pipe reactor with a recirculating reaction zone and a plug reaction profile reaction zone, especially when operated with a significant part of the overall conversion taking place in the plug reaction profile reaction zone.