Abstract: A microfluidic system includes a bubble valve for regulating fluid flow through a microchannel. The bubble valve includes a fluid meniscus interfacing the microchannel interior and an actuator for deflecting the membrane into the microchannel interior to regulate fluid flow. The actuator generates a gas bubble in a liquid in the microchannel when a sufficient pressure is generated on the membrane.

Abstract: A device for interrupting or throttling undesired ionic transport through a fluid network is disclosed. The device acts as a fluid valve by reversibly generating a fixed “bubble” in the conducting solvent solution carried by the network. The device comprises a porous hydrophobic structure filling a portion of a connecting channel within the network and optionally incorporates flow restrictor elements at either end of the porous structure that function as pressure isolation barriers, and a fluid reservoir connected to the region of the channel containing the porous structure. Also included is a pressure pump connected to the fluid reservoir. The device operates by causing the pump to vary the hydraulic pressure to a quantity of solvent solution held within the reservoir and porous structure. At high pressures, most or all of the pores of the structure are filled with conducting liquid so the ionic conductance is high.

Abstract: The present invention relates to fluidic systems, including switches for fluidic systems. The switches of the present invention may be particularly applicable to microfluidic systems. The switches of the invention may include a switching region having more than one position corresponding to more than one aspect ratio. Alternatively, the switches of the invention may include multiple inlets and a system for the selective supply of carrier fluid. The present invention also relates to a method of controlling a fluid in a microfluidic system and may be performed using the switches of the present invention.

Abstract: A modular microfluidic system includes a plurality of discrete microfluidic modules each capable of performing at least one operation and at least one microfluidic coupling device for fluidically coupling the modules to perform a sequence of operations. The microfluidic modules and coupling devices may be constructed according to various techniques. In one embodiment, coupling devices are fabricated from multiple layers and each include a fluidic inlet port, a fluidic outlet port, and at least one sandwiched stencil layer having a microfluidic channel formed therein. Also described are integrated microfluidic systems and methods capable of performing various sequences of operations.

Abstract: The disclosure describes a magnetorheological fluid control valve. The magnetorheological fluid control valve comprises an electromagnetic coil having a first end and a second end. A first arm is magnetically coupled to the first end of the electromagnetic coil. A second arm is magnetically coupled to the second end of the electromagnetic coil. The second arm has a passage. A ferromagnetic rod having a diameter less than that of the passage is disposed in the passage and magnetically coupled to the first and second arms. A first manifold is coupled to the second arm at one end of the passage. A second manifold is coupled between the second arm and the first arm at an end of the passage opposite the first manifold. A magnetorheological fluid is disposed in the passage.

Abstract: A flow pipe and one or more permanent magnets placed in or on the flow pipe, each permanent magnet presenting at its axial ends an infinite divergence of the magnetic field it generates. Fluid is treated by flowing through a flow pipe equipped with at least one such permanent magnet. The permanent magnet can be made of a plastic coextrudate with a ferromagnetic material such as iron powder, iron dust or iron chips. The permanent magnets can be arranged in groups with flow turbulence initiators positioned within the flow pipe between the magnet groups.

Abstract: Methods devices and systems that employ non-mechanical valve modules for controlling directing fluid and other material movement through integrated microscale channel network. These non-mechanical valve modules apply forces that counter the driving forces existing through a given channel segment, via fluidly connected channel segments, so as to selectively arrest flow of material within the given channel segment.

Abstract: Methods devices and systems that employ non-mechanical valve modules for controllably directing fluid and other material movement through integrated microscale channel networks. These non-mechanical valve modules apply forces that counter the driving forces existing through a given channel segment, via fluidly connected channel segments, so as to selectively arrest flow of material within the given channel segment.

Abstract: Microfluidic systems and devices having integrated fluidic impedances are provided. Such impedances hinder the passage of fluid at low differential pressures, but allow fluid flow at higher differential pressures. Impedances are formed at the overlap of two or more microfluidic channels contained in different layers of a device. Such devices can be rapidly prototyped and can be assembled to contain multiple fluidic impedances to perform complex fluid handling tasks, including the metering of small aliquots from a larger fluid volume. Various means may be used to overcome the fluidic impedances.

Abstract: A microfluidic flow control device includes a fluidic chamber, a first and a second microfluidic channel, at least one sealing surface between the first and the second channels, and a floating element disposed within the chamber. The floating element is capable of intermittently engaging the sealing surface, and movement of the floating element affects fluid flow between the first channel and the second channel. The floating element may be moved by fluid pressure, gravity, or an applied force such as a magnetic field. Multiple flow control regions may be integrated into a flow control system.

Abstract: A microfluidic reactor for performing chemical and biological synthesis reactions, including chemical and biological syntheses of organic, polymer, inorganic, oligonucleotide, peptide, protein, bacteria, and enzymatic products is provided. Two fluids are input into the device, mixed in a mixing region and provided to a long, composite reaction channel. Fluids flowing through the reaction channel may be diverted at a diversion region into a sample channel. Fluids in the sample channel may be mixed at a second region, with additional reagents.

Abstract: Disclosed is a micro flowguide device comprising: a micro channel comprising at least one bubble trap to retard bubbles positioned in said bubble trap; an electrolytic bubble generating device to generate bubbles in said fluid by an electrolytic reaction; and a pressure source to supply a suited pressure to said fluid to pass through said micro channel; wherein said electrolytic bubble generating device causes bubbles to be generated at areas adjacent to said at least one bubble trap. Electrolytic bubbles are generated through a, localized electrolytic reaction enabled by the exposure of a set of DC-source-connected electrodes inside a conduit branch. Accumulated bubbles will be trapped and kept at several traps of the invented flowguide. When the backward pressure of trapped bubbles is rising to the level of forward pressure head, flow speed reduces to zero and channel branch is shut down.

Abstract: A method for assembling a pattern of structures in a microchannel comprises providing a colloid of paramagnetic particles in a microchannel and applying an axially uniform magnetic field thereto.

Abstract: Methods of concentrating materials within microfluidic channel networks by moving materials into regions in which overall velocities of the material are reduced, resulting in stacking of the material within those reduced velocity regions. These methods, devices and systems employ static fluid interfaces to generate the differential velocities, as well as counter-current flow methods, to concentrate materials within microscale channels.

Abstract: Methods devices and systems that employ non-mechanical valve modules for controllably directing fluid and other material movement through integrated microscale channel networks. These non-mechanical valve modules apply forces that counter the driving forces existing through a given channel segment, via fluidly connected channel segments, so as to selectively arrest flow of material within the given channel segment.

Abstract: There is provided a downhole device for controlling the flow of fluids through an oil and/or gas production well comprises a deformable chamber which contains an electromagnetic field or other stimuli responsive gel and a fluid passage which is closed off in response to a volume increase of the gel and the deformable chamber.

Abstract: With a method of controlling the flow in a flow system where a liquid flow contains a particle concentration, the liquid flow is surrounded by a carrier liquid. The liquid flow and carrier liquid are led into a central channel in which there is provided an observation area (4) where measurements of the liquid flow are effected. The result of the measurements are used to lead the liquid flow into one of several channels, in that control liquids are introduced into the liquid flow before this reaches the channels, the control liquids being derived from a capillary pump structure which pumps on the basis of an electro-kinetic effect, e.g. an electro-osmotic effect. In a preferred embodiment, the pump structure consists of two capillary structures, to each of which an electrical field can be applied. Depending on the strength of the field, the amount of control liquid will be able to be controlled so that the liquid flow with the particle concentration can be led to one of two channels.

Abstract: The present invention relates to a method of fabricating a microfluidic device including at least two substrates provided with a fluid channel, comprising the steps of:

Abstract: The present invention provides multi-layer microfluidic systems, by providing additional substrate layers, e.g., third, fourth, fifth and more substrate layers, mated with the typically described first and second layers. Microfabricated elements, e.g., grooves, wells and the like, are manufactured into the surfaces between the various substrate layers. These microfabricated elements define the various microfluidic aspects or structures of the overall device, e.g., channels, chambers and the like. In preferred aspects, a separate microscale channel network is provided between each of the substrate layers.

Abstract: The present invention provides, in certain embodiments, improved microfluidic systems and methods for fabricating improved microfluidic systems, which contain one or more levels of microfluidic channels. The inventive methods can provide a convenient route to topologically complex and improved microfluidic systems. The microfluidic systems provided according to the invention can include three-dimensionally arrayed networks of fluid flow paths therein including channels that cross over or under other channels of the network without physical intersection at the points of cross over. The microfluidic networks of the invention can be fabricated via replica molding processes, also provided by the invention, utilizing mold masters including surfaces having topological features formed by photolithography.

Abstract: A microchip device has at least one passage along which a liquid can be moved by applying a voltage to the liquid. The device includes a passage member (10, 12) in which the passage is formed and which has an aperture (20, 22). Additionally the device includes an electrode member (14) that comprises an electrode (42, 44) and that is separably engageable with the passage member. The device includes a reservoir in fluid communication with the passages for holding a liquid. The electrode member cooperates with the aperture so that the electrode is in fluid communication with the passage without the electrode member obstructing the opening of the reservoir.

Abstract: A dielectric gate and related systems and methods for controlling fluid flow. A dielectric gate includes one or more electrodes coupled between an inlet fluid pathway and an outlet fluid pathway. The electrodes are configured to draw fluid from the inlet fluid pathway to the outlet fluid pathway in a precise manner by using dielectric forces arising from electrical signals applied to the electrodes.

Abstract: The present invention relates to a valve for use in a microfluidic system. The valve includes a substrate defining an upstream channel and a downstream channel joined by a passage, wherein the passage comprises a first opposed wall disposed at an angle to a central axis of the upstream channel. A thermally responsive substance (TRS) obstructs the passage. At least a portion of the TRS that obstructs the passage abuts the first opposed wall. Upon the actuation of the heat source in thermal contact with the TRS an opening motion of the TRS opens the passage.

Abstract: A valve (105) controls fluid flow in a microfluidic system (100). The valve (105) has an input port adapted to receive fluid exerting a predetermined level of pressure on the valve (105) and an output port. The valve (105) has a variable sized aperture disposed perpendicular to the flow of the fluid (119). The aperture varies in size between a relatively small aperture (137) and a relatively large aperture (151). The small aperture (137) prevents the flow of the fluid (119) through the valve (105) responsive to a relatively high level of capillary forces between the fluid (119) and the valve (105) in the small aperture (137). The large aperture (151) permits the flow of the fluid (119) through the valve (105) responsive to a relatively low level of capillary forces between the fluid (119) and the valve (105) in the large aperture (151).

Abstract: In a device for ejecting small amounts of a liquid material having accurately defined volumes from a chamber (1), the chamber has a nozzle aperture (7) and a rod (9) is mounted in or attached to a wall of the chamber (1), so that an end surface (11) of the rod is located opposite and at a small distance of the nozzle aperture (7). A driving device is coupled to the rod (9) for displacing the end surface (11) forwards and backwards inside the chamber with a very small stroke, with a high acceleration and a large force, so that a pressure wave is formed and propagates in the material in the chamber (1). The pressure wave then ejects material out of the nozzle aperture (7).

Abstract: The present invention relates to a device for controlling a liquid flow in a liquid channel, comprising: an elongate liquid holder in which a liquid channel is provided in longitudinal direction; first voltage means for applying a first voltage difference over substantially the longitudinal direction of the liquid channel; a conductor member arranged in at least a part of the liquid channel against the liquid holder; an insulator member arranged in the liquid channel against at least the conductor member; second voltage means for providing a second voltage difference between the conductor member and the liquid in the liquid channel; wherein the thickness of the insulator member is a maximum of 1 &mgr;m and preferably in the order of magnitude of some tens of nanometres.

Abstract: A device (10) for treating a continuously moving liquid has a liquid inlet (12) and a liquid outlet (14) at opposite ends of a generally annular passage (16). The passage has a restriction (18) which is generally cylindrical and which, at its outlet (22) is formed with an annular shoulder (24) which provides an abrupt change in the diameter of the passage. An obstruction (26) in the form of a wire extends across the restriction (18) adjacent the outlet (22). The restriction (18) serves to increase the speed of liquid flowing through the passage, thus reducing the liquid pressure. The obstruction (26) also assists in reducing the liquid pressure. The device reduces the liquid pressure below a level at which cavitation occurs in order to induce cavitation.

Abstract: A microchip device has at least one passage along which a liquid can be moved by applying a voltage to the liquid. The device includes a passage member (10,12) in which the passage is formed and which has an aperture (20,22). Additionally the device includes an electrode member (14) that comprises an electrode (42,44) and that is separably engageable with the passage member. The device includes a reservoir in fluid communication with the passages for holding a liquid. The electrode member cooperates with the aperture so that the electrode is in fluid communication with the passage without the electrode member obstructing the opening of the reservoir.

Abstract: The present invention provides multi-layer microfluidic systems, by providing additional substrate layers, e.g., third, fourth, fifth and more substrate layers, mated with the typically described first and second layers. Microfabricated elements, e.g., grooves, wells and the like, are manufactured into the surfaces between the various substrate layers. These microfabricated elements define the various microfluidic aspects or structures of the overall device, e.g., channels, chambers and the like. In preferred aspects, a separate microscale channel network is provided between each of the substrate layers.

Abstract: An electroösmotic mixing device and a method for mixing one or more fluids for use in meso- or microfluidic device applications. The mixing device provides batch or continuous mixing of one or more fluids in meso- or microfluidic channels. An electric field is generated in the channel in substantial contact with chargeable surfaces therein. No alterations of the geometry of existing flow paths need be made, and the degree of mixing in the device can be controlled by the length of the electrodes, the flow rate past the electrodes, and the voltage applied to those electrodes. The degree of mixing is affected by choice of materials for the chargeable surface (in some cases by the selection of materials or coatings for channel walls) and the ionic strength of the fluids and the type and concentration of ions in the fluids. The ionic strength of fluids to be mixed is sufficiently low to allow electroosmotic flow.

Abstract: A method of controlling flow of a driven fluid in a channel, the channel being defined by an encircling wall, the method comprising the steps of sealing the channel with a sealing fluid immiscible in the driven fluid blocking the channel at an initial position, in which the sealing fluid has a first contact angle with the encircling wall and the driven fluid has a second contact angle with the encircling wall and the first contact angle is less than the second contact angle; and moving the sealing fluid in the channel by a force generated outside of the channel.

Abstract: Magnetically actuated fluid handling devices using magnetic fluid to move one or more fluids (gases or liquids or both) through microsized flow channels are provided. Fluid handling devices include micropumps and microvalves. Magnetically actuated slugs of magnetic fluid are moved within microchannels of a microfluidic device to facilitate valving and/or pumping of fluids and no separate pump is required. The magnets used to control fluid movement can be either individual magnets moved along the flow channels or one or more arrays of magnets whose elements can be individually controlled to hold or move a magnetic slug. Fluid handling devices include those having an array of electromagnets positioned along a flow channel which are turned on and off in a predetermined pattern to move magnetic fluid slugs in desired paths in the flow channel. The fluid handling devices of the present invention can handle gases and liquids simultaneously and thus can be made to be self-priming.

Abstract: Methods of concentrating materials within microfluidic channel networks by moving materials into regions in which overall velocities of the material are reduced, resulting in stacking of the material within those reduced velocity regions. These methods, devices and systems employ static fluid interfaces to generate the differential velocities, as well as counter-current flow methods, to concentrate materials within microscale channels.

Abstract: Magnetically actuated fluid handling devices using magnetic fluid to move one or more fluids (gases or liquids or both) through microsized flow channels are provided. Fluid handling devices include micropumps and microvalves. Magnetically actuated slugs of magnetic fluid are moved within microchannels of a microfluidic device to facilitate valving and/or pumping of fluids and no separate pump is required. The magnets used to control fluid movement can be either individual magnets moved along the flow channels or one or more arrays of magnets whose elements can be individually controlled to hold or move a magnetic slug. Fluid handling devices include those having an array of electromagnets positioned along a flow channel which are turned on and off in a predetermined pattern to move magnetic fluid slugs in desired paths in the flow channel. The fluid handling devices of the present invention can handle gases and liquids simultaneously and thus can be made to be self-priming.

Abstract: A valve (1) on the basis of electrorheological and/or magnetorheological fluids includes a fluid inlet channel (3) connected through a valve gap (5) to a fluid outlet channel (4). The valve gap is filled with an electrorheological and/or magnetorheological fluid and is bounded by bounding surfaces that are embodied as electrically energizable capacitor electrodes and/or coil arrangements, whereby the field excitation thereof acts on the fluid flowing through the valve gap. At least one bounding surface of the valve gap is embodied to be movable selectively toward and away from another bounding surface, so as to superimpose a squeeze mode and a flow mode of the electrorheological and/or magnetorheological effect. The valve gap may define a meandering or spiral flow path for the fluid. In this manner, a compact valve can provide high blocking pressures and high through-flow rates.

Abstract: A monolithic flow controller for controlling the rate at which a medicinal liquid is administered to a patient. The monolithic flow controller includes one or more virtual valves that, because of their relatively small opening size (less than 0.5 &mgr;m in diameter), only permit fluid to flow through the valve when a forward bias voltage is applied. If a reverse bias voltage or no voltage is applied, fluid flow through the opening is inhibited. The fluid rate through the device is monitored using two pressure sensors or a differential pressure sensor that determine the differential pressure along the flow path through the device or relative to the external ambient pressure. The flow through the device is equal to the product of the differential pressure and the conductance of the channel in the flow controller. A capacitive bubble sensor is optionally provided to detect bubbles in the medicinal liquid being administered to the patient.

Abstract: The present invention provides multi-layer microfluidic systems, by providing additional substrate layers, e.g., third, fourth, fifth and more substrate layers, mated with the typically described first and second layers. Microfabricated elements, e.g., grooves, wells and the like, are manufactured into the surfaces between the various substrate layers. These microfabricated elements define the various microfluidic aspects or structures of the overall device, e.g., channels, chambers and the like. In preferred aspects, a separate microscale channel network is provided between each of the substrate layers.

Abstract: An electromagnetic flow control valve for an electrically conductive liquid having a plurality of coils and yokes surrounding a non-metallic, such as alumina, tube through which an electrically conducting liquid, such as liquid metal, flows. Direct current applied to the coils causes retarding forces to be imposed on the flowing liquid. The electromagnetic flow control valve can be used in conjunction with a continuous caster where the electromagnetic flow control valve is in fluid communication with a tundish. Built-in galvanomagnetic probes measure changes in the applied magnetic field to determine the rate of flow of liquid metal through the device.

Abstract: The invention concerns a freeze vale (2) for controlling the flow of small quantities of liquid in a conduit (1). Further objects of the invention are a network of conduits, a method of opening a freeze valve and a process for the separation of liquid fractions, which all involve the freeze valves (2) of the invention. The freeze valve (2) s defined by a tubular wall (3) integral with the conduit (1) and includes a thermal bridge (4) connecting the wall to a heat sink (5), to close the valve by freezing the liquid inside the wall, as well as a heating element (11) including a source of laser beam targeted at a wall, to open the valve by melting the frozen liquid (7). According to the invention the laser beam (13) is produced in the form of a transversally extended shroud and targeted at the wall (3) at a length extending to both sides of the point of connection (6) to the thermal bridge (4), so as to melt the block of frozen liquid (7) simultaneously along its entire length.

Abstract: A microfabricated device and method for proportioning and mixing biological or chemical materials by pressure- or vacuum-driven flow is disclosed. The microfabricated device mixes a plurality of materials in volumetric proportions controlled by the flow resistances of tributary reagent channels through which the materials are transported. The microchip includes two or more tributary reagent channels combining at one or more junctions to form one or more mixing channels. By varying the geometries of the channels (length, cross section, etc.), a plurality of reagent materials can be mixed at a junction such that the proportions of the reagent materials in the mixing channel depend on a ratio of the channel geometries and material properties. Such an approach facilitates flow division on the microchip without relying on techniques external to the microchip.

Abstract: A method and system for controlling the flow of a gaseous medium through a fluid are described. The method includes providing a rheologic fluid through which a gaseous medium can be conducted, and controlling the viscosity of the rheologic fluid to control the flow of the gaseous medium. The system has a rheologic fluid, which is located in particular in a device to be controlled, a guide guiding the gaseous medium through the fluid, and a field applier for applying a field at least partially in the area of the rheologic fluid.

Abstract: Structure with elements includes a main body of the element used in gas stream and a plurality of fluid passage. Each outlet of the fluid passage is opened on surface of the main body. Coolant fluid flows from each outlet through the passage to cover the surface as a film-like fluid. The plurality of fluid passages include first fluid passages and second fluid passages. The coolant fluid flows from the outlet of the first fluid passage along the direction of the gas stream on the surface. On the other hand, the coolant fluid also flows from the outlet of the second fluid passage toward the gas stream neighbored on each outlet of the first fluid passage.

Abstract: The present invention provides multi-layer microfluidic systems, by providing additional substrate layers, e.g., third, fourth, fifth and more substrate layers, mated with the typically described first and second layers. Microfabricated elements, e.g., grooves, wells and the like, are manufactured into the surfaces between the various substrate layers. These microfabricated elements define the various microfluidic aspects or structures of the overall device, e.g., channels, chambers and the like. In preferred aspects, a separate microscale channel network is provided between each of the substrate layers.

Abstract: An apparatus designed to manufacture a relatively large quantity of living water for a home or business. The apparatus includes a plurality of ampuls longitudinally aligned and connected together to enable the water delivered to the upper ampul to flow in a vortex pattern from the upper ampul to the lower ampul. Each ampul has a water dispensing unit which facilitates the flow of the water in a vortex pattern therein. Each ampul includes a longitudinally aligned neck with several pairs of magnets longitudinally aligned on the neck that create magnetic fields around the water as it flows in a vortex pattern through the neck. The apparatus is designed to be connected to a household water supply system and includes an optional holding tank and control valve.

Abstract: A controllable valve assembly (18) applicable in Magnetorheological (MR) fluid devices (20), such as MR mounts and MR dampers. The valve assembly (18) includes a valve body (32) having a magnetic circuit (40) contained therein which carries magnetic flux .phi., a controllable passageway (42) within the magnetic circuit (40), a MR (magnetically controlled) fluid (44) including soft-magnetic particles in a liquid carrier contained in the controllable passageway (42), a magnetic flux generator, such as a wound wire coil (46), generating magnetic flux .phi. which is directed through the MR fluid (44) in the controllable passageway (42) thereby generating "rheology" changes causing restriction in flow of MR fluid (44) therethrough.

Abstract: An electrically operated device (10) for treatment of hardness of water in a pipe or other waterflow guidance or containment, and which includes an aerial (11) capable of being wrapped externally around a pipe (12); a mains-powered generator (13) for forming a waveform of a predetermined pattern and at a radio frequency; an output connection (15) on the generator to which the aerial can be connected to receive the waveform; and means for varying the frequency of the waveform to suit the diameter of pipe with which the device is to be used.

Abstract: The present invention provides a use of an electro-sensitive movable fluid, that is, a micromotor, a linear motor, a micropump and a method of using the micropump, a microactuator, and an apparatus which these devices are applied to, and a method and an apparatus of controlling flow properties of a fluid.

Abstract: Structure with elements includes a main body of the element used in gas stream and a plurality of fluid passage. Each outlet of the fluid passage is opened on surface of the main body. Coolant fluid flows from each outlet through the passage to cover the surface as a film-like fluid. The plurality of fluid passages include first fluid passages and second fluid passages. The coolant fluid flows from the outlet of the first fluid passage along the direction of the gas stream on the surface. On the other hand, the coolant fluid also flows from the outlet of the second fluid passage toward the gas stream neighbored on each outlet of the first fluid passage.

Abstract: A microfabricated device and method for proportioning and mixing electrokinetically manipulated biological or chemical materials is disclosed. The microfabricated device mixes a plurality of materials in volumetric proportions controlled by the electrical resistances of tributary reagent channels through which the materials are transported. The microchip includes two or more tributary reagent channels combining at one or more junctions to form one or more mixing channels. By varying the geometries of the channels (length, cross section, etc.), a plurality of reagent materials can be mixed at a junction such that the proportions of the reagent materials in the mixing channel depend on a ratio of the channel geometries and material properties. Such an approach facilitates voltage division on the microchip without relying on external wiring schemes and voltage division techniques external to the microchip.

Abstract: A gas flow valve comprises at least one gas inlet, at least one gas outlet, a flow path between said gas inlet and said gas outlet, a magnetic fluid in the valve arranged in the flow path and means for application of a magnetic field to the magnetic fluid. The magnetic fluid solidifies upon application of the magnetic field, interrupts the flow path from at least one gas inlet to at least one gas outlet gas-tight and permits gas flow when no magnetic field is applied.