Abstract: A device for controlling a fluid flow in an array of fluid pathways on a microfluidic chip is provided. The device comprising: two or more resistors provided upstream of the chip wherein each upstream resistor is configured to provide a resistance at an upstream end of a fluid pathway; two or more resistors provided downstream of the chip wherein each downstream resistor is configured to provide a resistance at a downstream end of a fluid pathway, wherein the values of the resistances are selected in order to control a proportion of fluid that flows through each fluid pathway.

Abstract: A device for controlling a fluid flow in an array of fluid pathways on a microfluidic chip is provided. The device comprising: two or more resistors provided upstream of the chip wherein each upstream resistor is configured to provide a resistance at an upstream end of a fluid pathway; two or more resistors provided downstream of the chip wherein each downstream resistor is configured to provide a resistance at a downstream end of a fluid pathway, wherein the values of the resistances are selected in order to control a proportion of fluid that flows through each fluid pathway.

Abstract: An apparatus for monitoring the condition of a pressure relief safety valve, which has a magnetic ball shiftable from a home position by fluid under pressure when the relief valve opens, and an adjacent sensor responsive to shifting of the ball to provide a signal representing an open valve.

Abstract: A compressor oil management and separation system for refrigeration installations, including a main oil storage tank, a pump, valves and remote control means for selectively directing oil from the tank to any one or more of several compressors. Oil separation units are connected for collecting oil from low pressure refrigerant and delivering such separated oil to the tank for reuse or disposal. Each oil separation unit includes a collection vessel, valves for selectively alternately connecting the vessel with low pressure refrigerant and the tank, and means for increasing pressure within the vessel for forcing oil toward the tank.