635 results about "Tubular membrane" patented technology

There is described a prosthetic valve to be inserted into a body lumen, the valve having leaflets that are spread apart during forward flow of fluid to create an orifice, and the leaflets coming into contact with each other during reverse flow of fluid, thereby impeding the reverse flow of fluid, the valve comprising: a hollow, cylindrical stent having an inner surface and an outer surface, and having a first and a second open end; and valve means formed from a single tubular membrane, the membrane mounted to the stent, the membrane having a graft portion internally folded and bonded to itself at a plurality of points to form pouches such that the leaflets extend from the pouches, and a sleeve portion on an outer surface of the stent to secure the membrane thereto.

There is described a prosthetic valve to be inserted into a body lumen, the valve having leaflets that are spread apart during forward flow of fluid to create an orifice, and the leaflets coming into contact with each other during reverse flow of fluid, thereby impeding the reverse flow of fluid, the valve comprising: a hollow, cylindrical stent having an inner surface and an outer surface, and having a first and a second open end; and valve means formed from a single tubular membrane, the membrane mounted to the stent, the membrane having a graft portion internally folded and bonded to itself at a plurality of points to form pouches such that the leaflets extend from the pouches, and a sleeve portion on an outer surface of the stent to secure the membrane thereto.

Disclosed is a bifurcated tubular endoluminal vascular prosthesis, useful in treating, for example, an abdominal aortic aneurysm. The prosthesis comprises a self expandable wire support structure surrounded at least in part by a flexible tubular membrane. A delivery catheter and methods are also disclosed.

This invention relates to a stack comprising a continuous solid-phase matrix and tubular fuel cells embedded in the matrix. Each fuel cell comprises an inner electrode layer, an outer electrode layer, and an electrolyte layer sandwiched between the inner and outer electrode layers. The matrix is sufficiently porous to allow a first reactant to flow through the matrix and to the outer electrode of each fuel cell, and have sufficient mechanical strength to support the fuel cells in the stack. The fuel cells are embedded such that a second reactant may be flowed through the inside of each tubular fuel cell and to the inner electrode thereof. Alternatively, a stack of tubular separation membranes or a stack of tubular membrane reactors may be embedded in the matrix. The matrix material may comprise solid state foam, metal filament, or metal, cermet, or ceramic wool.

The invention provides a process for producing a tubular membrane assembly comprising helically winding at least one strip of fibrous material on a mandrel to produce at least a single ply tubular support member for a semi-permeable membrane, characterized by passing the strip through a heated section of the mandrel during the helical winding thereof to flatten and smooth fibers protruding along the cross-sectional width of the strip, whereby a tube with a smooth inner bore along its entire length is formed.

A flexible diffuser membrane is provided with a unique system of perforations arranged to result in uniform distribution of gas even though the membrane deflects to different extents or the submergence varies in different parts of the membrane. The perforations are arranged to provide less perforation area per unit of perforated membrane surface area in the membrane parts that deflect the most or are submerged least and greater perforation area in membrane parts that deflect the least or are submerged most. The perforations can be slits arranged in parallel rows on a tubular membrane, in concentric circles or another pattern on a disk membrane, or in still a different pattern on a flat panel diffuser membrane. The slit length or separation can be varied between different zones on the membrane surface or the spacing between rows or circles can be varied.

A method and apparatus for producing a synthesis gas product having one or more oxygen transport membrane elements thermally coupled to one or more catalytic reactors such that heat generated from the oxygen transport membrane element supplies endothermic heating requirements for steam methane reforming reactions occurring within the catalytic reactor through radiation and convention heat transfer. A hydrogen containing stream containing no more than 20 percent methane is combusted within the oxygen transport membrane element to produce the heat and a heated combustion product stream. The heated combustion product stream is combined with a reactant stream to form a combined stream that is subjected to the reforming within the catalytic reactor. The apparatus may include modules in which tubular membrane elements surround a central reactor tube.

The present invention relates to a medical device and method of forming the medical device. In particular, the present invention relates to a medical device having a tubular membrane structure over a radially expandable structural frame, and to a method of forming the tubular membrane on the radially expandable structural frame. In one aspect, a structural frame is placed over a spinning mandrel and a fiber is electro-statically spun over at least a portion of the structural frame forming a membrane. A transfer sheath may be used between the mandrel and structural frame to prevent the electro-statically spun fiber from adhering to the mandrel. In another aspect, a first membrane is spun over the mandrel before the structural frame is placed over the mandrel. In this aspect, at least a portion of the structural frame is sandwiched between the membranes. The membrane or membranes and structural frame form a fiber spun frame assembly. The fiber spun frame assembly may be coated with an elastic polymer. In addition, the membrane or membranes may go through some post processing to achieve desired characteristics or configurations.

A medical lead and method of treating a patient are provided. The medical lead comprises an electrically insulative tubular membrane, a resilient spring element associated with the insulative membrane, and at least one electrode associated with the insulative membrane. The medical lead is configured to be collapsed into a compact form for percutaneous delivery into the patient, thereby obviating the need to perform an invasive surgical procedure on the patient. The body formed by these elements, when expanded, can be sized to fit within the epidural space of a patient. The patient can be treated by placing the medical lead into a collapsed state by applying a compressive force to the medical lead, percutaneously delivering the collapsed medical lead into the patient adjacent tissue to be treated, and placing the medical lead into an expanded state by releasing the compressive force. In one preferred method, the stimulation lead is used to stimulate tissue, such as spinal cord tissue.

The invention discloses a method for preparing hollow fiber membranes and tubular membranes with a microporous PTFE hybrid flat membrane wrapping method. Dispersed PTFE resin and polyvinylidene fluoride resin are mixed with a liquid lubricant, and microporous PTFE hybrid flat membranes are prepared from the mixture through extrusion, calendaring, stretching and sintering. Then the microporous PTFE hybrid flat membranes are cut into membrane strips which wrap around supporting tubes, and finally the wrapped supporting tubes are sintered to obtain the hollow fiber membranes and the tubular membranes. The polyvinylidene fluoride resin added into the products of the invention has a melting point around 160 DEG C, fuses while sintered at a temperature between 250 and 340 DEG C, and can largely increase the hardness of the flat membranes after solidification, which facilitates slitting of the flat membranes. During the process of sintering after wrapping, the polyvinylidene fluoride resin contained in the flat membranes fuses again when sintered at a temperature between 260 and 340 DEG C, and thus can be used as overlapping parts between the wrapped flat membranes and as binders between the flat membranes and the microporous supporting tubes, so that the bonding strength is substantially improved.

The invention provides an external anaerobic membrane bioreactor comprising an anaerobic tank, a tubular membrane component, tubular ultrafiltration membrane elements and a clear water tank, wherein the tubular ultrafiltration membrane elements are vertically arranged in parallel in the tubular membrane component. The invention also provides a corresponding waste water purification technology of the external anaerobic membrane bioreactor. The waste water purification technology includes the steps as follows: firstly conducting purification treatment on waste water to be treated in the anaerobic tank, collecting biogas which is generated after treatment, filtering and separating the treated waste water in sequence by a fine grating and the tubular ultrafiltration membrane elements, at last leading out the leached clear water, backwashing and chemically washing the tubular ultrafiltration membrane elements at time intervals, drip-washing the collected biogas, and then pumping the biogas together with sewage into the tubular ultrafiltration membrane elements, so that the washing effect of the inner walls of the tubular ultrafiltration membrane elements can be improved. As for the external anaerobic membrane bioreactor and the waste water purification technology thereof, the energy consumption in operation is low, the quality of effluent is good, and blockage does not happen easily.

A tubular membrane module and its method of manufacture are disclosed wherein tubular membranes form an interference self-sealing fit with hard tube sheets with the aid of a hard hollow mandrel inserted at the end of the tubular membranes. The tubular membranes are comprised of porous, compressible PTFE and / or fluorocopolymers. The self-sealing method described herein requires no heat treatment, allows for ease of manufacture without destruction of the tubular membranes and without the processing complexity of utilizing any additional potting agent, extrusion, or chemical cross-linking of any polymeric adhesives. The self sealing PTFE tubular membranes have superb chemical resistance and temperature resistance, and through the benefits of this invention, offer higher pull-out resistance than typically observed with potting materials such as polyurethane and epoxy. In addition, the self-sealing method is reversible and non-destructive (whereas chemical potting and sealing methods using heat are not), as one can easily remove one or more damaged tubes and replace them.

The invention relates to an electric heating textile based on a carbon nano tubular membrane. The electric heating textile based on the carbon nano tubular membrane comprises a heating layer, textile protection layers and bonding layers, wherein the upper and lower surfaces of the heating layer are stuck with the textile protection layers by the bonding layers; and the heating layer is the carbon nano tubular membrane. The electric heating textile has the characteristics of stability of heating, uniform temperature, safety, comfort, lightness, portability and the like.

A module and an apparatus incorporating such module utilizing a plurality of tubular membrane elements, each configured to separate oxygen from an oxygen containing feed stream when an electric potential difference is applied to induce oxygen ion transport in an electrolyte thereof. The tubular membrane elements can be arranged in a bundle that is held in place by end insulating members. The insulating members can be positioned within opposed openings of end walls of a heated enclosure and can incorporate bores to allow an oxygen containing feed stream to flow past exposed ends of the tubular membrane elements for cooling the end seals of such elements. Further, first and second manifolds can be provided in a module in accordance with the present invention to collect separated oxygen from two separate portions of the tubular membrane elements.