216 results about "Permselective membrane" patented technology

The invention consists of a sensor with multiple indicating (sensing) electrodes covered with a selectively permeable membrane for monitoring fluid concentrations in a biological environment. The indicating electrodes respond to changes in certain analytes, such as glucose, through an enzyme-mediated reaction. The currents generated from the enzyme-mediated reactions are transmitted through radio signals to an external receiver where the information is processed and recorded. Through the use of various biomaterials and biochemicals associated with the sensor, the monitoring accuracy is improved and the overall viability is prolonged. The process of foreign body fibrosis (formation of a scar capsule around the implanted sensor) eventually limits the functional life of the device. We teach methods of delivery of certain biochemicals that can increase the functional life of the sensor by inhibiting the formation of the foreign body capsule or by stimulating the growth of capillaries into the capsule.

An electronic system and method for detecting analytes, such as carbon dioxide, is provided, using an improved nanostructure sensor (CO2 sensor). The CO2 sensor may comprise a substrate and a nanostructure, such as a one or more carbon nanotubes disposed over the substrate (e.g., as a network). One or more conductive elements may electrically communicate with the nanostructure. A counter or gate electrode may be positioned adjacent the nanostructure. A functionalization material reactive with carbon dioxide may be included, either disposed in contact with the nanostructure or isolated by a dielectric. The sensor may be connected to a circuit responsive to changes in CO2 concentration in the environment. Embodiments are described of medical sensing systems including one or more CO2 sensors. One embodiment comprises a breath sampling cannula which is connected to a sensor unit. In an alternative, the cannula permits supplemental oxygen to be administered, while recovering and measuring analytes in breath samples. The cannula may connect to a portable processor-display unit for monitoring one or more analytes, such as CO2. Another embodiment includes a cannula configured for the monitoring of sleep disorders, such as apnea, comprising one or more sensors disposed adjacent a breath sampling channel, optionally including flow rate or other sensors. The sensors may be connected by wired or wireless links for to a processor/input/display unit. Any of the embodiments may include filters, selectively permeable membranes, absorbents, and the like to precondition the breath sample, may be configured to include complementary chemistry measurements.

A method and apparatus for depositing III-V material is provided. The apparatus includes a reactor partially enclosed by a selectively permeable membrane 12. A means is provided for generating source vapors, such as a vapor-phase halide of a group III element (IUPAC group 13) within the reactor volume 10, and an additional means is also provided for introducing a vapor-phase hydride of a group V element (IUPAC group 15) into the volume 10. The reaction of the group III halide and the group V hydride on a temperature-controlled substrate 18 within the reactor volume 10 produces crystalline III-V material and hydrogen gas. The hydrogen is preferentially removed from the reactor through the selectively permeable membrane 12, thus avoiding pressure buildup and reaction imbalance. Other gases within the reactor are unable to pass through the selectively permeable membrane.

In the invention, the pipe lines around permselective membranes and the surfaces of permselective membranes are intermittently disinfected by adding an inexpensive acid such as sulfuric acid or the like to pre-treated crude water so as to make the water have a pH of 4 or lower. Accordingly, the invention provides a method of surely disinfecting the permselective membranes in membrane separation systems.

Compositions and processes are disclosed for economical separation of fluid mixtures. Broadly, the present invention discloses ionic polymer compositions that are useful for perm-selective membrane separations. More particularly, ionic polymers of the invention comprise a plurality of repeating structural units having as a constituent part thereof organic ionic moieties consisting of nitrogen containing anions and/or cations. In the form of non-porous membranes, ionic polymers of the invention facilitate recovery of purified organic and inorganic products from fluid mixtures by means of perm-selective membrane separations. The present invention also provides methods for forming the ionic polymers, for example by treating selected nitrogen-containing organic polymers with acids, or treating a polymeric material comprising a plurality of carboxylate groups with an amine. Ionic polymer compositions of the invention are particularly useful for simultaneous recovery of a permeate product of an increased concentration, and a desired non-permeate stream, from a fluid mixture containing at least two compounds of different boiling point temperatures.

Embodiments of the present invention provide various multipolymers and permselective membranes for use with biosensors and other implantable medical devices and prostheses. Embodiments of the present invention may provide structural strength and integrity, and further may control the influx of glucose, oxygen and/or water. Embodiments of the present invention may, for example, minimize or reduce the influx of glucose by minimizing the percentage of hydrophilic segments, which in turn minimizes the percentage of water uptake and the degree of glucose transport.

A system for suppressing fire in an enclosed space, e.g. an aircraft cabin or freight compartment, includes nitrogen tanks and/or generators to rapidly supply a limited quantity of nitrogen with a high flow rate, and a membrane system to supply an essentially unlimited quantity of nitrogen at a lower supply rate for a long duration. The membrane system includes a selectively permeable membrane that separates nitrogen gas from ambient environmental air that is supplied into the membrane system. Once a fire is detected, nitrogen is supplied from the nitrogen gas tanks and/or generators at a high rate to rapidly increase the nitrogen concentration and establish a reduced oxygen concentration (e.g. 12 vol. %) in the enclosed space. Then, nitrogen is supplied from the membrane system at a reduced rate for a long duration to maintain the reduced oxygen concentration in the enclosed space until the fire is extinguished by oxygen starvation.

A versatile compartmentalized cell culture device, with a selectively permeable membrane separating the compartments, provides many attributes relative to traditional devices. It can be configured for high-density cell culture, co-culture, and sample dialysis while rolling or standing still. It can also be configured for continuous movement of liquid between compartments. The wide combination of attributes not found in other membrane based cell culture and bioprocessing devices includes more cell capacity, more cell secreted product capacity, higher cell and product density, increased medium capacity, minimized use of exogenous growth factors, compatibility with standard cell culture equipment and protocols, increased scale up efficiency, capacity to function when rolling or standing still, capacity for perfusion without the need for pumps, and more efficient sample dialysis.

There is provided a hybrid heat pump system. The system includes (i) a membrane permeator having a permselective membrane capable of selectively removing vapor from a vapor-containing gas to yield a dry gas, (ii) a heat pump having (a) an internal side for exchanging thermal energy with a process fluid, (b) an external side for exchanging thermal energy with an external environment, and (c) a thermodynamic mechanism for pumping thermal energy between the internal side and the external side in either direction, (iii) means for conveying the vapor-containing gas into the membrane permeator, and (iv) means for routing the dry gas to either of the internal side or the external side.

The present invention relates to a membrane being suitable for, for example, hemodialysis. Said membrane comprises at least one hydrophobic polymer and at least one hydrophilic polymer. According to the present invention the outer surface of the hollow fiber has pores in the range of 0.5-3 μm and the numbers of said pores in the outer surface are in the range of 10,000 to 150,000 pores per mm², preferably in the range of 18,000 to 100,000 pores per mm², and most preferably in the range of 20,000 to 100,000 pores per mm². The present invention further relates to a process for the preparation of said membrane and use of said membrane in hemodialysis, hemodiafiltration and hemofiltration, and in dialysis and filtration in general, for example in water purification or dehydration.

A hydrogen permselective membrane, a method of forming a permselective membrane and an apparatus comprising a permselective membrane, a porous substrate and an optional intermediate layer are described. Using chemical vapor deposition (CVD) at low reactant gas concentration, high permselectivities are achieved with minimal reduction in hydrogen permeance.

Disclosed is a permselective membrane module comprising i) two permselective membrane elements formed of hollow fibers arranged substantially in parallel and bundled together and ii) a container, the two elements being arranged in the container longitudinally of the hollow fibers, wherein the respective elements comprise i) a feed tube disposed longitudinally of the hollow fibers and ii) a hollow fiber bundle covering the outer surface of the feed tube, the feed tube having a number of holes therein, and the hollow fibers having one end closed and the other end opened, wherein the feed tubes of the two elements communicate with each other via a connecting tube to form a conduit having one end opened and the other end closed, and wherein the container comprises i) an inner wall surrounding the two elements with a space, ii) a feed port provided at one end of the container in communication with the opened end of the conduit, iii) a permeate-liquid outlet facing the open end of the hollow fiber bundle of each element and extending through the container wall, and iv) a non-permeated fluid discharge outlet communicating with the gap between the container and the outer surface of each element and extending through the container wall.

A hydrogen permselective membrane, a method of forming a permselective membrane and an apparatus comprising a permselective membrane, a porous substrate and an intermediate layer are described.

A permselective membrane type reactor 100 comprises:

• • a cylindrical reaction tube 1 having a gas inlet 11 at one end and a gas outlet 12 at the other end,
  • a cylindrical, bottomed, separation tube 2 inserted into the reaction tube 1, which is made of a porous material and has a permselective membrane 3 at the surface, and
  • a catalyst layer 4 provided between the reaction tube 1 and the separation tube 2, for promotion of chemical reaction. The reactor 100 further comprises, at a location apart from the permselective membrane 3, an oxygen-containing gas feeding section 20 which extends in the gas-flowing direction of the reaction tube 1 and feeds an oxygen-containing gas from multiple positions to the catalyst layer 4 in the gas-flowing direction.

A permselective material has a polymer having an organosiloxane skeleton and containing a dispersed solid additive. When oxygen and nitrogen are passed through a membrane having the permselective material, the relation between the permeability coefficients [cm³·cm·sec⁻¹·cm⁻²·cmHg⁻¹] of oxygen and nitrogen at a temperature of 23±2° C. under a pressure difference of 1.05 atm to 1.20 atm through the membrane is expressed by Formula (1):

where P(O₂) denotes the permeability coefficient of oxygen, while P(N₂) denotes the permeability coefficient of nitrogen.

The invention relates to a high-flux molecular-sieve alcohol permselective membrane and a preparation method thereof. The high-flux molecular-sieve alcohol permselective membrane is composed of a support body and a membrane layer, wherein the support body is yttrium-stabilized zirconia porous material, the membrane layer is a Silicalite-1 molecular sieve membrane, the average pore size of the support body is 0.1-5 mu m, and the porosity is 10-75%. The invention also discloses a preparation method of the hollow fiber alcohol permselective membrane. The alcohol permselective membrane has outstanding separating property. When the alcohol permselective membrane is used in an ethanol/water system, the permeation flux is enhanced by 3-20 times. The alcohol permselective membrane has higher separation factor and favorable repetitiveness, and especially has favorable effect since the alcohol permselective membrane is composed of the hollow fiber support body. The alcohol permselective membrane is used in the fields of permeating vaporization, gas separation and the like, and has important meaning in the industrial application of alcohol fermentation liquor concentration.

The invention provides a non-contact method for dehumidifying liquid and a dehumidifier. The method comprises the following steps that: dehumidifying saline solution and air are separated by a membrane; when the air flows from the surface on one side of the membrane, water vapor in the air passes through the membrane selectively to reach the other side of the membrane; and then, the water vapor is absorbed by the dehumidifying saline solution contacted with the membrane, but salt molecules and liquid water cannot pass through the membrane so as to dry the air. The dehumidifier comprises a shell, an air passage and a saline solution passage, wherein the air passage and the saline solution passage are separated by the membrane; and the membrane is placed in the shell, and is a permselective membrane, so that the water vapor can pass through the membrane but the saline solution cannot pass through the membrane. The method and the dehumidifier can effectively prevent salt in the solution from being brought into the air, thereby preventing occurrence of corrosion.

The present invention is a technique to fabricate thin-film composite perm-selective membranes by a transfer method. The composite membranes are useful in separating liquid, vapor or gaseous mixtures by selective permeation and reduce mass transfer resistance of the support layer. Selectivity and flux are improved by reduction of the mass transfer resistance of the support layer.

The invention relates to a method for preparing an organic-inorganic hybrid evaporation alcohol permselective membrane used for the separation of alcohol/water system. Micropore molecular sieves are modified chemically, organic functional groups are led in the structure and the modified micropore molecular sieves and silicone rubber are mixed and coated to prepare the organic-inorganic hybrid evaporation alcohol permselective membrane. The method is characterized in that: the organic functional groups in the modified micropore molecular sieves can enhance the interaction force between the modified micropore molecular sieves and the silicone rubber, or form stable compound bond phase between the two substances, thus weakening the boundary defect between the inorganic and organic phases, improving the separation performance of the membrane and avoiding the defects of the deterioration of boundary defect between the inorganic and organic phases and unstability of the membrane due to compression during the use process of the membrane.