2812 results about "Membrane surface" patented technology

The invention relates to membrane pumps for delivering liquids. More specifically, a pump is provided having a pump housing with a pump cavity formed between first and second wall portions thereof, and an pump membrane pump membrane having first and second membrane surfaces arranged within the pump cavity, whereby a pump chamber is provided between the first wall portion and the first membrane surface, and an actuation chamber is provided between the second wall and the second membrane surface. Inlet means comprising an inlet valve in fluid communication with the pump chamber, and outlet means comprising an outlet valve in fluid communication with the pump chamber are provided. The pump membrane has a maximum volume position, and a drained volume position in which the first membrane surface in a stretched state abuts the first wall. To drive the membrane, actuating means for periodically shifting the pump membrane between the maximum volume position and the drained volume position is provided, thereby, in a situation of use, providing a flow of fluid.

A heat and humidity exchanger comprises a pleated membrane cartridge disposed in a housing. The cartridge comprises a pleated water-permeable membrane via which heat and humidity can be transferred between two fluid streams. A flow field element is disposed within some or all of the folds of the pleated membrane, for directing the stream over the inner surfaces of the folds. The flow field path defined by the flow field element enhances flow distribution across one or both membrane surfaces, controlling the relative flow paths of the two streams on opposite sides of the membrane and reducing the pressure drop across the heat and humidity exchanger. The flow field elements provide improved water transfer and allow for a more compact device. The flow field elements can also assist in supporting the pleated membrane and controlling the pleat spacing within the pleated membrane cartridge. The heat and humidity exchanger is particularly suitable for fuel cell and energy recovery ventilator (ERV) applications.

The invention is to a dual beam process for providing an ion-conducting membrane with a thin metal or metal-oxide film. The process includes the cleaning of a membrane surface with a low energy electron beam followed by the deposition of the metal or metal-oxide film by a high energy electron beam of ions.

A finished flooring underlayment is disclosed including a flexible membrane which is resistant to water, mold and deterioration under wet or dry conditions, and which has intertwined filaments bonded to the membrane surface that act as mortar reinforcement and as gauges to provide a uniform thickness of application for cementicious mortar. The mortar is provided separately and is mixed to a suitable consistency with either water or latex additive, then poured or placed on the mat, utilizing the gauges provided by the filaments to effect a uniform thickness of application. This mortar hardens to a strong, load bearing surface or slab suitable for application of finished flooring.

The present invention provides a sugar-modified liposome having a sugar chain bonded to its membrane surface, preferably through a linker protein, and having excellent absorption qualities, particularly in the intestine. The molecular structure and quantity of the sugar chain is selectively varied to allow the liposome to be delivered in a targeted manner to selected cells and tissues. The liposome is applicable to medicinal drugs, cosmetics and other various products in the medical/pharmaceutical fields, and it is especially useful in a therapeutic drug delivery system that recognizes target cells and tissues, such as cancer cells, and in the delivery of drugs or genes locally to a selected region, or in a diagnostic cell/tissue sensing probe.

A submerged membrane assembly including a membrane having a first surface, a second surface, and a vertical axis, and which is permeable between the surfaces by molecules of less than a predetermined size. A first fluid compartment in fluid communication with the first membrane surface and that contains at a first column height a first fluid having a first specific gravity, a second fluid compartment in fluid communication with the second membrane surface and that contains at a second column height a second fluid having a second specific gravity, and means for changing the second specific gravity. The second column height being selected relative to the first column height to produce a selected pressure differential across the membrane along the vertical axis at the first specific gravity and the changed second specific gravity.

The present invention relates to a support structure/membrane composite device which includes a support structure, such as a radially expandable stent, a porous non-textile polymeric membrane adjacent to said stent and a thermoplastic anchor means attaching said stent to said porous non-textile polymeric membrane. The porous non-textile polymeric membrane is preferably made from expandable fluoropolymer materials. The anchoring means is a thermoplastic material which is dissolvable at the interface between the support structure and membrane by a suitable solvent which wets the membrane surface and deposits the thermoplastic material within the pores of the membrane. Methods of preparing the device are also disclosed.

Sterile coupling comprising a male and a female connector, each provided with a membrane device comprising a membrane surface covered with an adhesive at the exterior surface. When the connectors are brought into operation, the adhesive surface are contacted to form a bonded surface. Then, a hole is generated through the bonded surface and the sterile portions of the devices are brought into cooperations. The hole is formed by a rupture member arranged in one of the connectors. After rupturing, the membrane devices retract to a space formed between the cylindrical bodies of the connectors.

The invention discloses a method of producing the hyperfiltration membrane of amphiphilic copolymer modified polyvinylidene fluoride, comprising the following steps: 1) mixing polyvinylidene fluoride, poly (methyl methacrylate - monomethyl ether polyoxyethylene methyl methacrylate), additives, non-solvent and solvent to form the casting film solution; 2) making the casting film solution into the polyvinylidene fluoride membrane by using the film forming machine and then soaking in the coagulation bath; 3) conducting the posttreatment of hydrophilicity; 4)obtaining the hydrophilic polyvinylidene fluoride ultrafiltration membrane after cleaning and drying. The method is characterized in that the brush shape, chain ball shape or dumbbell shape amphiphilic copolymer are mixed with the polyvinylidene fluoride to produce the polyvinylidene fluoride hyperfiltration membrane with hydrophilicity, anti-pollution, large flux and high retention rate by adopting the solution phase conversion method. The method has the advantages that the obtained membrane is provided with dozens to hundreds nanometer of particular densified hydrogel surface layers, the contact angle of the membrane surface can be reduced below 60 degrees and can be lowered to 0 degree within tens of seconds, the water flux can reach 1000L /m<2>/ h (0.1Mpa) or above, the retention rate of BSA can reach 90% or more and the recovery rate of water cleaning flux can reach 90% or higher.

A capacitive vacuum measuring cell has a first housing body and a membrane, both of Al₂O₃ ceramic or sapphire. The membrane is planar with a peripheral edge joined by a first seal to the first housing body to form a reference vacuum chamber. A second housing body of Al₂O₃ ceramic or sapphire opposite the membrane, is joined to the peripheral edge of the membrane by a second seal to form a measurement vacuum chamber. A port connects the vacuum measuring cell to a medium to be measured. At least in the central area of the first housing body, an optical transparent window is formed and at least the central region of the membrane has an optically reflective surface. Outside the reference vacuum chamber, in opposition to and at a distance from the window, an optical fibre is arranged for feeding in and out light onto the surface of the membrane.

The present invention provides a microporous polyolefin membrane of high permeability and novel structure, and also provides a method of producing the same, wherein its average pore size is gradually decreases from at least one membrane surface towards its center. The method of producing the microporous polyolefin membrane comprises the steps of extruding the solution, composed of 10 to 50 weight % of (A) a polyolefin having a weight-average molecular weight of 5×105 or more or (B) a composition containing this polyolefin and 50 to 90 weight % of a solvent, into a gel-like formed article and removing the solvent therefrom, wherein a treatment step with a hot solvent is incorporated.

The invention discloses a method for fixing biological molecules on a polymer microporous membrane surface, comprising the following steps: (1) respectively dissolving DOPA compounds and the biological molecules in a trihydroxymethyl aminomethane - muriatic acid buffer solution and a phosphoric acid buffer solution to prepare solutions; (2) immersing a polymer microporous membrane in a DOPA compound solution and oscillating to cause the DOPA compounds to be auto-polymerized-compounded on the membrane surface and to be closely attached to the membrane surface and a membrane pore wall; (3) immersing the polymer microporous membrane modified by the DOPA compounds in a biological molecule solution, and fixing the biological molecules on the polymer microporous membrane surface by the addition reaction between catechol groups of the membrane surface and amidogen in the biological molecules. The method for fixing biological molecules on the polymer microporous membrane surface has simple process, the prepared polymer microporous membrane has good hydrophilic property and biocompatibility, and the method has important meaning for improving the permeability and the biocompatibility of the polymer microporous membrane.

A spiral membrane element having an enlarged effective membrane surface area without having its separation performance lowered, while maintaining the sealing property of any sealing portion of a cylindrically wound body, and a manufacturing method of the same are disclosed. The spiral membrane element includes a cylindrically wound body comprising a perforated central tube and, spirally wound therearound, a separation membrane, a feed-side passage material and a permeation-side passage material in a laminated state, and a sealing portion for preventing a feed-side fluid and a permeation-side fluid from being mixed together, wherein the sealing portion formed at each of both ends of the cylindrically wound body is spirally formed with a substantially constant width by an adhesive and has a trimmed section formed on its whole end surface, and the cylindrically wound body has a ratio of its length to the length of the central tube of 0.96 to 1.00, and a ratio of an ineffective membrane surface area to the entire membrane surface area of 0.02 to 0.10.

A method of cleaning a permeable, hollow membrane (6) in an arrangement of the type wherein a pressure differential is applied across the wall of the permeable, hollow membrane (6) immersed in a liquid suspension provided in a vessel (5), said liquid suspension being applied to the outer surface of the permeable hollow membrane (6) to induce and sustain filtration through the membrane wall. The method of cleaning comprising the steps of: suspending the filtration process; while continuing to supply the liquid suspension to the vessel (5); aerating the membrane (6) by flowing gas into the vessel (5) to produce a flow of gas bubbles around the membrane (6) to dislodge at least some of the retained particulate material from the membrane surface; removing liquid containing dislodged particulate material from the vessel (5) during the aerating step and recommencing the filtration process.

The invention relates to a method for preparing a large-scale two-dimensional nanomaterial graphite, comprising the following steps of: plating a nickel film with the thickness of 100-300nm on the surface of monocrystal silicon, and then injecting carbon element into the nickel film by adopting an ion implantation mode; annealing for 15min-1h at a high temperature between 600 DEG C and 1,000 DEG C and a vacuum degree of from (10-5)Pa to 1Pa, and cooling to room temperature so that carbon atoms are separated out from the nickel film and recombined. Therefore, a layer of graphite film (the film thickness depends on various experiment parameters, such as carbon injection content, and the like) can be formed on the surface of the nickel film. When a sample is put into a FeCl3 solution, the nickel film can be corroded, and the graphite film can be separated out and floats on the surface of the liquid; and at the moment, the graphite film can be transferred away from the liquid with any substrate. Therefore, the large-scale graphite film with the size of several centimeters can be prepared.

High flow, low-pressure ultrafiltration or microfiltration spiral wound membrane cartridges are used in filtration of liquid feedstocks having high suspended solids. Applications may utilize either vacuum or pumping for transmembrane drive pressure (TMP), and gas may optionally be bubbled up through the cartridges with certain feedstocks. Water permeate flux rates as high as 90 gallons per square foot per day (gfd) can be obtained at TMPs below 5 pounds per square inch. By locating each spiral wound cartridge in its own casing and supplying liquid feedstock to an open lower end of the casing, as opposed to submerging such cartridges in a tank filled with feedstock, overall low pressure performance is greatly improved. High permeate flow can be maintained for long periods of time between shutdowns for intensive cleaning. TMP is gradually increased to maintain a substantially constant rate of permeate discharge until a target is reached, indicative of solids accumulation on the membrane surface to an undesirable extent; then backflushing is effected for a short time. Discarding the hold-up volume of feedstock in the cartridge, the backflushing fluid and dislodged solids, allows production to be promptly resumed with fresh feedstock at performance at near original levels.