TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred System: The bulkhead has at least one passageway for fluid communication of an injectively-mixed backmixing reaction chamber product stream from the injectively-mixed backmixing reaction chamber into the tubular-flow reactor. The bulkhead provides the passageway with at least one aperture having a cross-sectional area. The reactor system has a blocking component for variably obstructing a portion of the cross-sectional area from passageway use during real-time operation of the reactor system. The bulkhead has at least one aperture as a first aperture. The blocking component has at least one, second aperture. The two apertures have identical dimensions and are mutually disposed to positionally align, in one relative positioning of the bulkhead and the blocking component, to define the passageway to have a cross-sectional area essentially equivalent to the cross-sectional area of the first aperture. The tubular-flow reactor has a tubular-flow reactor internal volume defined by a tubular-flow reactor housing and by the bulkhead. The slidable movement of the bulkhead toward the housing portion commensurately diminishes the injectively-mixed backmixing reaction chamber internal volume while expanding the tubular-flow reactor internal volume, and alternative slidable movement of the bulkhead away from the housing portion commensurately expands the injectively-mixed backmixing reaction chamber internal volume while diminishing the tubular-flow reactor internal volume. The injectively-mixed backmixing reaction chamber has two fluid inputs for the reactor system and a backmixing reaction chamber output. The tubular-flow reactor has a tubular-flow reactor input in fluid communication with the backmixing reaction chamber output. The first/second fluid input receives a first/second fluid feed stream into the injectively-mixed backmixing reaction chamber, respectively. The backmixing reaction chamber has a space-time of 0.05-1.5 seconds respective to a combined feed rate of the two fluid feed streams. Alternatively the reactor system comprises the injectively-mixed backmixing reaction chamber in fluid communication the a tubular-flow reactor such that the backmixing reaction chamber has the internal volume defined by an internal surface of a housing and a surface of a component (T1) in moveably sealed interface to the internal surface; and a component for modifying the internal volume and to move the component (T1) to modify the internal volume from a first internal volume to a second internal volume. The component for modifying the internal volume comprises the bulkhead in slideably sealed interface to the housing. A first fluid stream in the fluid feed streams comprises methane and a second fluid stream comprises oxygen. At least one alkyl oxygenate is manufactured through partial oxidation reacting of a first fluid stream in the fluid feed streams comprising an alkane-containing gas feed stream and a second fluid stream in the fluid feed streams comprising oxygen from an oxygen-containing gas feed stream. The injectively-mixed backmixing reaction chamber has an alkane gas input, an oxygen gas input, and a backmixing reaction chamber output. The tubular-flow reactor has a tubular-flow reactor input in fluid communication with the backmixing reaction chamber output. The alkane gas input receives the alkane-containing gas feed stream into the injectively-mixed backmixing reaction chamber. The oxygen gas input receives the oxygen-containing gas feed stream into the injectively-mixed backmixing reaction chamber. The injectively-mixed backmixing reaction chamber has a space-time, respective to a combined feed rate of the alkane-containing gas feed stream and the oxygen-containing gas feed stream, sufficient for induction of alkyl free radicals from the alkane within the injectively-mixed backmixing reaction chamber and for providing at least a portion of the alkyl free radicals to the tubular-flow reactor input. The alkane gas input and the oxygen gas input are configured to turbulently agitate the backmixing reaction chamber by injective intermixing of the alkane-containing gas feed stream and the oxygen-containing gas feed stream. The tubular-flow reactor has a tubular-flow reactor output, and at least one cooling gas input disposed between the tubular-flow reactor input and the tubular-flow reactor output for receiving a cooling gas stream and thus quenchably cooling the tubular-flow reactor. The tubular-flow reactor has an axis. The cooling gas input is moveable along the axis during operation of the tubular-flow reactor. The backmixing reaction chamber has an internal volume defined in part by a cylindrical surface having an injectively-mixed backmixing reaction chamber axis, and one feed stream of the feed streams is input into the internal volume from several apertures disposed along the axis and in non-parallel orientation to the axis. The injectively-mixed backmixing reaction chamber has an internal flow diverter defined by a conical surface having an axis. The diverter defines a conical base at one end of the axis. The conical surface defines an apexial end at the other end of the axis. The axis of the diverter is aligned with the axis of the backmixing reaction chamber. The diverter is disposed within the housing such that the backmixing reaction chamber output is more proximate to the apexial end than to the conical base. One feed stream of the feed streams is input into the internal flow space from several apertures disposed along the backmixing reaction chamber axis and in non-parallel orientation to the backmixing reaction chamber axis. The bulkhead has at least one passageway for fluid communication of an injectively-mixed backmixing reaction chamber product stream from the backmixing reaction chamber into the tubular-flow reactor. The tubular-flow reactor has a tubular-flow reactor input in fluid communication with the backmixing reaction chamber output. The bulkhead provides the passageway with at least one aperture having a cross-sectional area. The tubular-flow reactor housing has an axis and two portions in threaded attachment to the backmixing reaction chamber housing. The reactor system further comprises: a blocking component for variably obstructing a portion of the cross-sectional area from passageway use during real-time operation of the reactor system; and a variable cooling gas input disposed in the second portion in spiral orientation along the axis for quenchably cooling the tubular-flow reactor with a cooling gas stream. The second portion of the tubular-flow reactor housing is in threaded attachment to the backmixing reaction chamber housing with threads that move the second portion along the axis when the second portion is rotated, and rotation of the second portion simultaneously repositions the bulkhead along the axis, the cooling gas input along the axis, and the blocking component to modify the cross-sectional area.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The alkane is methane, ethane, propane, or butane (preferably methane). The alkyl oxygenate comprises methanol, ethanol and further comprises formaldehyde.