302 results about "Stopped flow" patented technology

This invention relates to a novel microfluidic device and methods of using this device to conduct in vitro studies on the reaction and effects of various compounds on cells. More particularly, it relates to a method for using stop flow in a microfluidic system to study the effect of compounds on individual cells. It also provides a method for observing the effects of candidate compounds on leukocyte rolling.

The fluid delivery system generally includes a source of injection fluid, a pump device a fluid path set disposed between the source of injection fluid and the pump device, and a fluid control device. The fluid path set includes a multi-position valve. The fluid control device is operatively associated with the fluid path set and includes a valve actuator adapted to operate the multi-position valve. The valve actuator is adapted to close the multi-position valve to isolate the pump device from a patient and stop flow of the injection fluid to the patient at substantially any pressure or flow rate generated by the pump device for delivering a sharp bolus of the injection fluid to the patient. The valve actuator is generally adapted to selectively place the pump device in fluid communication with the source of injection fluid for supplying the injection fluid to the pump device and the patient.

The fluid delivery system generally includes a source of injection fluid, a pump device a fluid path set disposed between the source of injection fluid and the pump device, and a fluid control device. The fluid path set includes a multi-position valve. The fluid control device is operatively associated with the fluid path set and includes a valve actuator adapted to operate the multi-position valve. The valve actuator is adapted to close the multi-position valve to isolate the pump device from a patient and stop flow of the injection fluid to the patient at substantially any pressure or flow rate generated by the pump device for delivering a sharp bolus of the injection fluid to the patient. The valve actuator is generally adapted to selectively place the pump device in fluid communication with the source of injection fluid for supplying the injection fluid to the pump device and the patient.

According to principles of this invention, an override controller is structured for being placed in pressurized fluid lines between a valve position transducer and a valve position actuator of an automatic position-controlled valve assembly, with the override controller receiving uncontrolled supply pressurized fluid and having an exhaust. The override controller receives pressurized fluid at first and second inlet ports from the valve position transducer and furnishes this pressurized fluid to the valve position actuator through first and second outlet ports for controlling the position of the valve during normal operation. However, valve mechanisms of the override controller can also be placed in positions for stopping flow of pressurized fluid through the first and second inlet ports and providing fluid flow from the uncontrolled pressurized fluid to the first and second outlet ports for controlling the position of an industrial valve during override operation.

A valve that is sealable to an associated container having an interior fluid storage region is adapted to permit and stop flow of fluid from the fluid storage region. The valve includes a body sealable to the container and a stem mounted to the body having a portion in flow communication with the storage region. The stem is movable relative to the body between an open position to permit flow from the storage region through the valve, and a closed position to stop flow through the valve. The stem has a grasping region spaced from the body that is adapted rotate the stem to move the valve between the open and closed positions. The grasping region has first and second sides. One of the sides has a tactile indicator to provide indication of the position of the valve, the other side is devoid of the tactile indicator.

An automatic stop valve formed in a container of a medical fluid administration system includes an electrical field that attracts the float and valve seat together to shut off flow from the exit port of the container when the fluid within the container is reduced to a predetermined level. One or both of the float and valve seat creates an electric field that attracts the other, which is made of a non-magnetic dielectric, into engagement. In one embodiment, the valve seat is formed of an electret that creates the electric field attracting the float to it to stop flow. In another embodiment, the float comprises an electret that attracts the float to the dielectric valve seat. In yet another embodiment, both the float and valve seat include electrets of opposite polarity that attract each other into engagement. The lack of magnetic and metallic materials makes the shut off valve suitable for use in an MRI environment.

A bodily fluid analyzer including a test strip holder comprising a base and a snap-on cover which completely enclose the test strip except for a sample port in the cover and a sensor port in the base. The test strip is compressed between the base and cover in a sample container having a well-defined sample volume. The test strip comprises a woven dispersement layer, a depth filter containing a reagent, an asymmetrical membrane containing additional reagent, and a colorimetric detection membrane in a vertical stack. The red blood cells are removed from the colorimetric detection area by slowing their vertical movement and stopping flow when the detection membrane is saturated. A minimum value of the reflectance in a color range is used to determine a characteristic of the bodily fluid.

The invention relates to a disposable centrifugal type plasma separator; a hemostix, a plasma filter pipeline, a separation cup and a blood storage bag are connected to form a transport channel in sequence; the hemostix comprises a blood taking needle and a catheter which is connected with the blood taking needle; the catheter is provided with a stop flow clip; the plasma filter pipeline comprises a puncture outfit, a blood filter and an air filter; the inputs of the puncture outfit and the blood filter are respectively connected with a tee interface by the catheter; the other end of the tee interface is connected with the catheter in the hemostix; the air filter is connected with one output of the blood filter by the catheter while the other output of the blood filter is connected with the input of the separation cup by the catheter; and the output of the separation cup is connected with the blood storage bag by the catheter. The invention has the advantages that as the disposable plasma collection consumables which are singly packaged originally are assembled, packaged and sterilized in the same purified environment, the risk of sterility connection for the parts is greatly reduced, and the workload of medical personnel is decreased, too.

A semi-conductor crystal and method of forming the same. The method includes providing a flow of dopant and column III element containing gases, then stopping flow of dopant and column III element containing gases, reducing the temperature, restarting flow of column III containing gases and then elevating the temperature.

Methods and fuel systems to reduce evaporative emissions of a volatile fuel. A fuel tank contains fuel, a carburetor mixes air with the fuel from the fuel tank, and a plurality of fluid paths route fuel amongst and / or between the fuel tank and the carburetor. A valve actuation device stops flow of fuel in one or more of the plurality of fluid paths and the carburetor is adapted to be drained of fuel during engine shutdown to reduce or prevent evaporative emissions from the fuel system. The carburetor is preferably designed so as to minimize a volume of fuel contained therein.

The invention relates to the field of ecological environment protection, in particular to a method used for afforesting a desert. The method used for afforesting the desert comprises the following steps of: 1, excavating a filling slot; 2, paving a waterproof impervious layer; 3, paving a sand layer; 4, paving a plant growing layer; and 5, paving a straw plaited grid. The waterproof impervious layer is arranged in the sand layer, the waterproof impervious layer stops flow direction of water, and water can not leak everywhere deep in the sand layer, thus the aim of saving water is achieved; the used material is environmentally friendly, and human and natural environment can not be polluted; water supply is reasonable, water can be uniformly supplied to plants used for afforesting, the plants can rapidly grow, and the problems of water for afforesting the desert and rainwater seepage control can be effectively solved. The method has a wide application field and is convenient for standardization construction. By applying the method to afforest the desert, a conditioned desert can be afforested, desert vegetation coverage rate can be improved, and a local ecological environment of the desert can be improved.

The invention discloses a method and equipment for automatically monitoring the water quality by measuring COD, ammonia nitrogen and pH in water by using the sequential injection analysis (SIA). Based on SIA, COD is measured by using the combination of Ce oxidation process and stopped flow-SIA method; ammonia nitrogen is measured by using the SIA-indigo intensity method of blue light; pH is measured by using the spraying wall electrode method. The invention measures COD, ammonia nitrogen and pH at the same time by using the on-line SIA technique. The invention provides features of on-line monitoring, simple structure, good accuracy and repeatability.

The invention discloses an in vitro bionic cycle test system for simulating flowing of blood in arterial aneurysm of a human body under different heartbeat frequencies, relating to the field of biomedicine research on arterial aneurysm and being suitable for carrying out cycle simulating testing on the flowing condition of the blood in the arterial aneurysm of the human body under different heartbeat frequencies. The in vitro bionic cycle test system comprises an upper liquid storage box, a peristaltic pump, a laminar flow generator, an experimental section model, a flow meter, a lower liquid storage box, a cycle pump and a valve. The whole in vitro bionic cycle test system is communicated by a silicon rubber hose and a common rubber hose, fluid is controlled by the valve to flow or stop flowing; the silicon rubber hose is connected to the upper liquid storage box and is downwards connected with the laminar flow generator through the peristaltic pump, a pump head of the peristaltic pump is used for carrying out peristaltic extrusion on the silicon rubber hose; and the laminar flow generator is formed by banding a thin tube embedded in the common rubber hose. Fluid flows out of the laminar flow generator, enters the experimental section model through the common rubber hose, flows into the lower liquid storage box through the flow meter, and returns to the upper liquid storage box through the cycle pump, so that the whole cycle flowing process is completed.

A variable-capacity compressor that includes a housing having an inlet for receipt of refrigerant and an outlet for return of refrigerant, and a plurality of compressing elements contained in the housing between the inlet and the outlet. The variable capacity compressor includes a valve having an electrical control. The valve is dedicated to fewer than all of the compressing elements. The valve is movable between a first state which communicates refrigerant flow to the compressing elements, and a second state that reduces or stops flow to the compressing elements. In an embodiment of the invention, an unloading controller has an operational modulation mode that includes cycling the valve between on and off states to provide a portion of compressor capacity. The unloading controller is further programmed to provide a minimum delay time between transitions between the first and second states, but no maximum dwell time between transitions.

This invention relates to wireless linkage layer flow control method, which comprises the following steps: a, in data transmission process, receive end tests memory space for data transmission data and triggers flow control end; b, receive end stops receiving sequence SN>=VR-H agreement unit AMD PDU; c, receive end sends repeat PDU information and adjusts send window information status report; d, if the receive end receives the repeat PDU within reset time and tests memory data linkage transmission data to certain valve value then stops flow control, otherwise for step c.

The present invention relates to an abnormal switching monitoring device and method. A time point when a high-side switch in which a first electrode receives an input voltage is turned on, a time point when a low-side switch that is connected to a second electrode of the high-side switch is turned on, a time point when a charge current begins to flow to a bootstrap circuit, and a time point when a charge current stops flowing to the bootstrap circuit are compared so as to determine whether or not non-zero voltage switching occurs. The bootstrap circuit supplies an operating current to a gate driver controlling a switching operation of the high-side switch.

The invention discloses a plugging agent and a preparation method thereof. The plugging agent comprises a composition of a water-soluble hydrophobic associated polymer or a water-soluble hydrophobic associated polymer. The preparation method of the plugging agent is a copolymerization cohydrolysis method or a copolymerization posthydrolysis method. The plugging agent easily enters a leakage layer and has good viscoelasticity, so that the plugging agent can pass a throat and expand to fill a leakage crack and a solution cave space, meanwhile, can automatically stop flowing in the leakage layer and is unlikely to mix with oil, gas and water, thus a gel 'slug' with high viscosity and gel strength, which is capable of separating fluid in formation from fluid in a shaft, is formed; and the slug has enough starting pressure difference greater than the difference between the pressure of a mud column and the pressure of the formation fluid so as to achieve the purpose of plugging. The plugging agent and the preparation method thereof can be used for effectively solving various serious leakage and have good application value and social value.

A system and method for controlling the flow rate of a gaseous sample in an exhaled breath analysis system is disclosed. Two embodiments are described in this patent: a single pump embodiment and a dual pump embodiment. In each of these embodiments, a pump or pumps are used to control the flow rate of the breath sample as it moves through the analysis system. Also, the system includes means to conduct side stream, stopped flow analysis.

A microfluidic system and method, suitable for "lab-on-a-chip" applications, by which a bubble is inflated in fluid flowing through a microfluidic channel at a predetermined location along the channel and the bubble is maintained at that location to stop flow through the channel in the manner of a valve. The microfluidic channel is formed on a semiconductor chip and a pair of electrodes is formed one on each side of the channel, whereby a bubble is electrochemically inflated between the electrodes and held in fixed position by the channel wall when a voltage is applied across the fluid incident to connecting the electrodes to a voltage source. When the voltage is removed, deflation of the bubble valve rapidly occurs to restore flow. The present invention provides flow control in a microfluidic system regardless of channel cross-sectional geometry and with no moving parts and low power consumption. Moreover, the present invention may be practiced using existing fabrication techniques.

The invention discloses a gel plugging agent which is prepared from the following raw materials in percentage by weight: 4-8% of sodium polyacrylate, 15-25% of staple, 0.05-0.1% of ammonium persulfate, 1-5% of methylacryloyloxyethyltrimethyl ammonium chloride, 15-25% of wood meal and the balance of acrylamide. Besides, the invention also discloses a preparation method of the gel plugging agent. When in use, the gel plugging agent is firstly mixed with water to form a plugging slurry; the plugging slurry can easily enter the cracks or leakage zone of the rock pores, stay and generate generation blockage; the staple in the plugging slurry quickly huddles, the sodium polyacrylate quickly expands, and the staple and sodium polyacrylate quickly form a bridge, so that the plugging slurry slowly stops flowing in the cracks and rock pores; and the acrylamide generates chain polymerization reaction and condenses into a hard solid, and is cemented with the leakage zone rock, thereby enhancing the plugging effect and enhancing the strength of the loss zone.

A welding cable connector system having a male connector and a female connector. The male connector includes a first conductive body for conveying welding power. The male connector also includes a first sealed passageway disposed coaxially of the first conductive body for conveying shielding gas, and a first Schrader valve configured to stop flow of shielding gas when the male connector is not engaged. The female connector includes a second conductive body for conveying welding power. The female connector also includes a second sealed passageway disposed coaxially of the conductive body for conveying shielding gas, and a second Schrader valve configured to stop flow of shielding gas when the female connector is not engaged. The male and female connectors are mutually engageable to conduct welding power and shielding gas therethrough. The first and second Schrader valves seal the flow of shielding gas when the connectors are not mutually engaged.

The invention discloses a multi-taste beverage distributing spray nozzle and an distributor using the same, wherein the distributing spray nozzle comprises at least one water inlet, at least two thick juice inlets, a main water flowing path penetrating the spay nozzle and at least two thick juice flowing paths penetrating through the spray nozzles, wherein the thick juice flowing paths are communicated with each thick juice inlet through fluid and are respectively stopped at thick juice discharge openings. By using the water flowing paths, water is sprayed from the spray nozzle in a curtain shape and is preferably annular; the thick juice discharge opening comprises a thick juice deflector by which the thick juice is dispersed in a sector shape to impact a water curtain when flowing out of the discharge opening. The spray nozzle comprises at least two auxiliary water flowing paths by which water transfers from the main water flowing path and the transferred water penetrates through at least two thick juice discharge openings for discharging. On the downstream, the spray nozzle comprises a convex surface and water is gathered around the convex surface when stopping flowing. The beverage distributor uses a plurality of multi-taste beverage distributing spray nozzles. The distributor also comprises distributing spray nozzles for distributing a taste addictive; and the distributing spray nozzles can be used for distributing ice; even the distributor is provided with an ice crusher, thereby distributing crushed ice or block ice.