Certain embodiments described herein are directed to chromatography systems that include a microfluidic device and that implement one or more methods to direct sample to a desired fluid flow path. The methods can be used to backflush a sample to a desired fluid flow path to select certain analytes within a sample.

A regulating device may include a housing that defines an inlet chamber and an outlet chamber, with a flow restriction seat between the inlet chamber and the outlet chamber. A flow restriction valve is movable relative to the flow restriction seat to adjust the flow between the inlet chamber and the outlet chamber of the regulating device. A servo valve having a servo chamber may be used to adjust the position of the flow restriction valve. The servo chamber may be fluidly coupled to the inlet chamber though a fixed flow restriction and to the outlet chamber though an adjustable flow restriction. A stepper motor may be used to adjust the servo valve to adjust the adjustable flow restriction between the servo chamber and the outlet chamber. This causes a change of the servo pressure, which moves the flow restriction valve and adjusts the flow of the regulating device.

A liquid block apparatus integrated into a sample probe that is inserted into the pressurized process to prevent entrained liquids from entering the probe and being extracted for sampling. The present invention enhances sampling of pressurized process fluids for on-stream and spot sampling of pressurized process fluid such as natural gas or the like, particularly pressurized process gas having liquid entrained therein, or otherwise referenced as multiphase or wet.

Microfluidic structures and methods for manipulating fluids, fluid components, and reactions are provided. In one aspect, such structures and methods can allow production of droplets of a precise volume, which can be stored/maintained at precise regions of the device. In another aspect, microfluidic structures and methods described herein are designed for containing and positioning components in an arrangement such that the components can be manipulated and then tracked even after manipulation. For example, cells may be constrained in an arrangement in microfluidic structures described herein to facilitate tracking during their growth and/or after they multiply.

Assay cartridges are described that have a detection chamber, preferably having integrated electrodes, and other fluidic components which may include sample chambers, waste chambers, conduits, vents, bubble traps, reagent chambers, dry reagent pill zones and the like. In certain embodiments, these cartridges are adapted to receive and analyze a sample collected on an applicator stick. Also described are kits including such cartridges and a cartridge reader configured to analyze an assay conducted using an assay cartridge.

The invention relates to a device for dispensing one or more jets of cryogenic fluid comprising a fluid supply pipe supplying one or more fluid-dispensing nozzles arranged downstream of said pipe, in which the fluid flow section of the fluid supply pipe has a first diameter. According to the invention, the device for dispensing one or more jets of cryogenic fluid also comprises at least one plenum chamber which is arranged between the fluid supply pipe and the fluid-dispensing nozzle(s) and which is fluidly connected to both the pipe and the nozzle(s). The fluid flow section of each plenum chamber has a second diameter greater than the first diameter of the fluid flow section of the fluid supply pipe.

A method of and apparatus for controlling pressure in a process chamber having a continuous gas inlet flow and a continuous gas outlet flow comprising providing a pulsed valve at a gas outlet, a pressure gauge, and a programmable controller and varying the pulse rate of the pulsed valve, wherein either the open time or closed time, or both open and closed times, is lengthened or shortened, depending on whether the gauge pressure is above or below the programmed setpoint.

A hemodialysis system is disclosed. The hemodialysis system includes a dialyzer and an online dialysate generation system comprising a water inlet line and a drain line. The hemodialysis system also includes a disposable set comprising a supply tube fluidly connected to online dialysate generation system and a dialysate pumping tube fluidly connected to the dialyzer. The hemodialysis system further includes a dialysis instrument comprising a dialysate pump head and a motor positioned and arranged to operate the dialysate pump head. The dialysis instrument operates the dialysate pump head to move fresh dialysate from the online dialysate generation system through the dialysate pumping tube to the dialyzer.

Methods and systems are provided for controlling operational parameters of a CO.sub.2 compression surface facility or pipeline in order to maintain a CO.sub.2 stream having impurities flowing in the pipeline in a liquid or supercritical phase. Sensors may be provided to sense whether the flow is single-phase or two-phase flow, and feedback provided to adjust the pressure and/or temperature at the pipeline inlet. The system is preferably optimized to limit power consumption and/or cost.

The invention provides methods of making laminated devices (especially microchannel devices) in which plates are assembled and welded together. Unlike conventional microchannel devices, the inventive laminated devices can be made without brazing or diffusion bonding; thus providing significant advantages for manufacturing. Features such as expansion joints and external welded supports are also described. Laminated devices and methods of conducting unit operations in laminated devices are also described.