Abstract: A system for maintaining back-pressure in chemical laboratory testing apparatus includes a modified flow control valve governed by a special control system which includes an input/output controller. That controller includes a microprocessor and memory into which a program developed specifically for the modified valve has been placed. A pre-pressure valve is also used upstream of the instrument in which the pressure is to be maintained for effecting quicker control of the pressure. The input/output controller, in conjunction with the servo-amplifier, integrates out the error between the desired set-point pressure and actual pressure thereby enabling maintenance of pressure within one pound.

Abstract: A reactor tube of a microreactor assembly including a first central temperature sensor and a channel formed in its outer surface to circulate a coolant. A tightly fitting conductive core surrounds the cooling channel and is sealed to the reactor tube at both ends to confine the coolant except for inlet and outlet holes. Around that core a metallic tube is fitted having a longitudinal slot to which a second temperature sensor is fixed. A heating element to heat the tube and the reactor tube is disposed on the slotted tube and second sensor so that temperature changes on the outer wall of the reactor tube-core sub-assembly can be detected. Both the first and second temperature sensors are adapted to feed output signals to a controlling data processing unit.