Abstract: Disclosed are various turbulent, corrosion-resistant heat exchangers used in desiccant air conditioning systems.

Abstract: A dishwasher with a tub at least partially defining a treating chamber, a liquid spraying system supplying a spray of liquid to the treating chamber, a liquid recirculation system defining a recirculation flow path, and a liquid filtering system having a rotating filter. A chopping system is included to macerate foreign objects within the recirculation flow path and includes a blade mounted to the rotating filter.

Abstract: Membranes comprising a single layer having a first microporous surface; a second microporous surface; and, a porous bulk between the first microporous surface and the second microporous surface, wherein the bulk comprises a first set of pores having outer rims, prepared by removing introduced dissolvable silica nanoparticles, the first set of pores having a first controlled pore size, and a second set of pores connecting the outer rims of the first set of pores, the second set of pores having a second controlled pore size, and a polymer matrix supporting the first set of pores, wherein the first controlled pore size is greater than the second controlled pore size, and wherein the first and/or second microporous surface comprises a neutrally charged, a negatively charged, or a positively charged, surface; filters including the membranes, and methods of making and using the membranes, are disclosed.

Abstract: It is an object to achieve a closed system that has a simple structure without resorting to large scale equipment and that sequentially carries out all of the step of separating useful cells, the step of culturing the useful cells separated in the separation step, and the step of washing and concentrating the cells cultured in the culturing step and to enable the preparation of useful cells having high safety and quality, while improving operability.

Abstract: Disclosed is a rechargeable lithium battery that includes a positive electrode including a lithium nickel-based positive active material; a negative electrode including a negative active material; an electrolyte including a lithium salt and a non-aqueous organic solvent; and a separator including a polymer substrate and a hydroxide compound-containing coating layer disposed on the polymer substrate.

Abstract: Disclosed herein are methods of making sterilized ciprofloxacin compositions. In some embodiments, the method includes the steps of: (a) forming an aqueous suspension comprising ciprofloxacin particles; (b) heating the aqueous suspension comprising ciprofloxacin particles at a temperature range of from about 100° C. to about 120° C.; and (c) allowing the aqueous suspension comprising ciprofloxacin particles to cool down. Also described herein are otic formulations containing ciprofloxacin formed by the disclosed methods, and therapeutic use of such otic formulation for providing sustained release of ciprofloxacin into the ear for treating various otic disorders and conditions.

Abstract: A dishwasher with a tub at least partially defining a washing chamber, a liquid spraying system for spraying liquid within the washing chamber, a liquid recirculation system defining a recirculation flow path, and a liquid filtering system. The liquid filtering system includes a rotating filter disposed in the recirculation flow path to filter the liquid.

Abstract: This invention relates to an electric double layer capacitor electrochemical cylinder (11) made up of concentric layers of capacitors (16), current collectors (14a, 14b, 14c), ion specific membranes (18, 18a, 18b) and dielectric spacer (20) wrapped around an inner support tube (12) that can be used as a high capacitance capacitor and to remove dissolved solids from a liquid stream such as water, acid, aqueous or non-aqueous.

Abstract: An object selecting device includes a container configured to store liquid, a plate configured to support a selection object by being immersed into the liquid stored in the container, and a holder configured to hold the plate in a state where a bottom surface of the plate and an inner bottom part of the container are separated. The plate includes a through hole at a support position. The through hole includes a tapered portion configured to allow the selection object to precipitate along a direction of gravity and support the selection object in contact with the inner wall surface of the through hole. An opening area at the upper end of the tapered portion is larger than that at the lower end of the tapered portion. Only the selection object can be supported out of the collection of objects having different shapes.

Abstract: An electrochemical separation membrane and the manufacturing method thereof are disclosed. The method includes: a polymer solution preparing step to mix a polymer material, solvent and ceramic precursors thoroughly to form a polymer solution, wherein the polymer material and the ceramic precursors are dissolved uniformly in the solvent; a coating step to coat the polymer solution on a porous base material; a hydrolysis step to cause the porous base material coated with the polymer solution to contact an aqueous solution to hydrolyze the ceramic precursor into ceramic particles; and a drying step to remove the water and the solvent from the porous base material and in order to form the electrochemical separation membrane. The electrochemical separation membrane made of this method have better ion conductivity, interface stability and thermal stability based on the ceramic particles.

Abstract: A water softening system includes apparatus that recycles a substantial percentage of the solution used for regenerating the system. This system conventionally includes a brine tank and a softening tank through which hard water from a source passes during normal operation. During a regeneration mode, the solution of sodium or potassium ions in the brine tank passes through the softening tank acquiring hardness ions, and then through a nanofilter that passes a much higher proportion of the sodium or potassium ions than the hardness ions from a high pressure side to a low pressure side. The hardness ions flow from the upstream end of the nanofilter through an outlet and into a drain. The liquid passing through the nanofilter contains salt that returns to the brine tank for reuse. Concentration of sodium or potassium ions may be tested during a fast rinse portion of the regeneration cycle.

Abstract: A substrate with a surface-collection-layer includes a honeycomb substrate having a porous partition wall that defines and forms cells, and a plurality of plugging portions. A surface-collection-layer is formed on a surface of the partition wall that forms the remaining cells, and the thickness of the surface-collection-layer on the outlet-side open end is larger than the thickness of the surface-collection-layer in a center area of the substrate. The partition wall has predetermined thickness, porosity, and average pore size. The surface-collection-layer has a predetermined thickness, porosity, and average pore size, and the substrate has a predetermined cell density.

Abstract: Provided herein is technology relating to isolating nucleic acids. In particular, the technology relates to methods and kits for extracting nucleic acids from problematic samples such as stool.

Abstract: Provided are cardo copolybenzimidazoles, a gas separation membrane using the same and a method for preparing the same. More particularly, provided are cardo copolybenzimidazoles obtained by introducing cardo groups and aromatic ether groups to a polybenzimidazole backbone, a gas separation membrane having significantly improved oxygen permeability by using the same, and a method for preparing the same. The cardo copolybenzimidazoles have improved solubility as compared to the polybenzimidazole polymers according to the related art, show excellent mechanical properties while maintaining thermal stability so as to be formed into a film shape, and provide a gas separation membrane having significantly improved gas permeability, particularly, oxygen permeability.

Abstract: Example embodiments relate to a membrane, a method of manufacturing the same, and a composite membrane including the same. The membrane may include a polyacrylonitrile-based copolymer that includes a hydrophobic side chain and/or a hydrophobic repeating unit. The membrane may include a skin layer and a porous layer. A thickness ratio of the skin layer relative to the porous layer may be about 0.01 or less. The skin layer may have a thickness of about 1 ?m or less. The membrane may have a relatively high water flux. When using the membrane, a water treatment module having higher energy efficiency may be achieved.

Abstract: A membrane for a method for filtration of gas effluents from an industrial installation including a wall having an internal surface and an external surface, the wall having pores of variable dimensions in the radial direction and in the longitudinal direction of the wall.

Abstract: A method for making a composite polyamide membrane including the steps of applying a polyfunctional amine monomer and polyfunctional acyl halide monomer to a surface of the porous support and interfacially polymerizing the monomers to form a thin film polyamide layer, wherein the method is includes at least one of the following steps: i) conducting the interfacial polymerization in the presence of a subject monomer comprising at least one carboxylic acid group linked to an aromatic moiety and wherein the aromatic moiety is further substituted with at least one of an acyl halide or anhydride functional group and ii) applying the subject monomer to the thin film polyamide layer. The invention includes many additional embodiments.

Abstract: Provided herein is technology relating to isolating nucleic acids. In particular, the technology relates to methods and kits for extracting nucleic acids from problematic samples such as stool.

Abstract: A filtering device uses a filtration unit for filtering raw water, and the filtration unit has a depth filter forming a filtration membrane thereof and a housing accommodating the depth filter. The housing includes a raw water inlet port for supplying the raw water to the depth filter, a filtrate water outlet port, a gas-supplying port for supplying compressed air into the filtration unit to clean the depth filter, and a drain port for discharging the compressed air together with the raw water. A pore diameter of the filtration membrane is designed within a range of 1 to 25 ?m. The filtering device includes a filtrate water supplying passage connected to the filtrate water outlet port, a discharge passage connected to the drain port, a communication passage for communicating filtrate water supplying passage with the discharge passage, and a motor valve for opening and closing the communication passage.

Abstract: This invention provides an apparatus and methods to consistently separate and concentrate selected blood components. The system includes, e.g., a computerized fluid handling system to transfer blood components between a centrifugal blood separation disc, containers and a concentrator.

Abstract: A membrane separation device includes a separation membrane unit A that has a separation membrane unit component 8, feed stream side lines F1 and F2, and a permeate stream line P, and a unit for feeding a stream-to-be-treated, wherein a stream-to-be-treated sealing material is provided in the perimeter of an anti-telescoping plate of the separation membrane element, wherein the separation membrane elements can be moved within a cylindrical pressure vessel substantially in either direction, wherein the separation membrane unit is configured to feed the stream-to-be-treated through one of the feed stream side lines F1 and F2 and to discharge the concentrate stream through the other of the feed stream side lines, and wherein the separation membrane unit includes a mechanism that can switch the flow between the feed stream side lines.

Abstract: There is provided a separation membrane unit wherein a plurality of separation membrane subunits (11a-c) communicate with raw water lines A (9a-c) that comprise raw water supply valves W (10a-c), water discharge lines B (12a-c) that comprise water discharge valves X (13a-c), raw water lines C (16a-c) that comprise first raw water communication valves Y (17a-c), raw water lines D (19a-c) that comprise second raw water communication valves Z (20a-c), and permeate water lines E (21a-c); and wherein the raw water lines A communicate with the water discharge lines B, the raw water lines C communicate with the raw water lines D, the raw water lines A communicate with a main raw water line 7, the water discharge lines B communicate with a main water discharge line 14, the raw water lines C and the raw water lines D communicate with a collection line 18, and the permeate water lines E communicate with a main permeate water line 22.

Abstract: Separation processes using osmotically driven membrane systems are disclosed generally involving the extraction of solvent from a first solution to concentrate solute by using a second concentrated solution to draw the solvent from the first solution across a semi-permeable membrane. Enhanced efficiency may result from using low grade waste heat from industrial or commercial sources. Pre-treatment and post-treatment may also enhance the osmotically driven membrane processes.

Abstract: Guanidinyl ligand-functionalized polymers, methods of making the same, and substrates bearing a grafted coating of the ligand-functional polymers are described. The grafted polymer has the requisite affinity for binding neutral or negatively charged biomaterials, such as cells, cell debris, bacteria, spores, viruses, nucleic acids, endotoxins and proteins, at pH's near or below the pI's of the biomaterials.

Abstract: An oily water separator for removing oil from oil-containing water, including a vessel, a filtration membrane unit and a discharge mechanism; the filtration membrane unit containing a filtration membrane module and a returning mechanism, the filtration membrane module for performing filtration in the state of allowing the module to be immersed into the oil-containing water; the filtration membrane module having an elongated filtration membrane with an opening portion, the opening portion of the filtration membrane being fixed to one end of the filtration membrane module, the opening portion of the filtration membrane being communicatively connected to the returning mechanism; the returning mechanism being extended along the filtration membrane toward an end on a side opposite to an end portion having the opening portion thereof, the returning mechanism being communicatively connected with the discharge mechanism.

Abstract: We provide a system and method for reverse osmosis treatment of water, including seawater and brackish water. Methods and systems of embodiments of the invention may include, for example, ultrafiltration followed by biofoulant removal, both of which precede reverse osmosis. In preferred embodiments the system is run at a low flux. For example, a flux of 6-8 GFD may be used with seawater. Additional embodiments may provide the above process in conjunction with a reverse-osmosis membrane cleaning system. The membrane cleaning system is a “clean in place” system that includes use of the natural pressure differential in the reverse osmosis system to remove biofoulants and their precursors.

Abstract: A method and an apparatus (10) for filtering and separating flow media (11) by means of membranes (13), including a substantially pressuretight housing (14) in which a plurality of membranes (13) is disposed, at least one inlet (15) for the flow medium (11) carried into the apparatus (10) and to be separated, and at least one outlet (16) for the permeate (18) discharged from the apparatus (10) and an outlet (17) for the discharged retentate (19), the membranes (13) being embodied on the order of membrane cushions, which have an opening region (131) for the emergence of the permeate (18) collecting in the membrane interior (137).

Abstract: A mechanical particle filter comprises a membrane having a plurality of pores. At least one partial region of the surface of the membrane, that is accessible for the medium to be filtered, includes a carbon material having a diamond structure.

Abstract: The present invention relates to a material. In particular, it relates to a membrane for filtering water. More particularly, it relates to a membrane comprising carbon nanotubes and mixed cellulose ester porous membranes for water desalination and purification. Still more particular, the membrane comprising a fibrous substrate and carbon nanotubes formed on a fibrous substrate, wherein the surface of the carbon nanotubes is functionally modified. A microfluidic device comprising such a membrane and a method for filtering water are also disclosed.

Abstract: An osmotic power generation system and method for generating osmotic power includes a membrane chamber having a semi-permeable membrane therein defining a first portion and a second portion therein. The system also includes a first pump communicating a first fluid to the first portion and a second pump communicating a second fluid to the second portion. The second fluid has higher total dissolved solids than the first fluid. A second portion energy recovery device is in fluid communication with the second portion. A power generator is in communication with the second portion energy recovery device generating electrical power in response to the second portion energy recovery device and the pressure in the second portion.

Abstract: An automatic locking system for a medical treatment device helps to ensure that an assistant is present during treatment of a patient. Among the features disclosed biometric authentication to verify that a trained assistant is present, a presence detector to ensure the assistant is continuously present during treatment, and warning and recovery processes that allow intermittent lapses in the continuous presence of the assistant.

Abstract: A method for increasing the shelf life of donor blood contemplates the following steps. In the first step blood is transferred to a sterile container and mixed with an anticoagulant as indicated in step 20. The anticoagulant and donor blood are centrifuged in step 22 at about 4,000 rpm for about 15 minutes. After centrifuging the red blood cells are separated and placed in a sterile tube. In the next step the red blood cells are irradiated by a laser that emanates a wavelength of about 633 nm for a time period of about 24 hours. During rotation the RBCs are rotated to provide uniform exposure. Such laser biostimulation produces an enhancement of shelf life of donor blood by 66%.

Abstract: A composite filter membrane cartridge, including a housing with a raw water inlet and a filtered water outlet is disclosed. The housing may be equipped with one or more filter layers, including a prefilter assembly and a second filter portion, wherein the prefilter is connected to the membrane filer either via a water line or by direct stacking. The prefilter assembly may include multiple layers comprising a carbon filter and polypropylene cotton filter, wherein the locations of the filters are interchangeable. The prefilter may include granular activated carbon situated between two portions of polypropylene cotton filter cloth. The perimeter of the activated carbon filter and polypropylene cotton filter may be substantially sealed around the inner wall of the housing providing a snug fit. The second filter portion of the composite filter membrane cartridge may include nanomembrane spiral wound filter.

Abstract: The present invention provides a method of testing the integrity of a microporous membrane using a colloid solution containing metal particles or metal compound particles that can accurately determine the integrity of a virus removal membrane formed of hydrophilized synthetic polymer that has been subjected to protein solution filtration, and to provide a method of producing the colloid solution. The colloid solution comprises a solvent and metal particles dispersed in the solvent, and the solvent comprises components (A) and (B), (A) and (C), or (A), (B), and (C), wherein the component (A) is an anionic polymer having a sulfonic acid group, the component (B) is at least one nonionic surfactant selected from the group consisting of a nonionic surfactant having a polycyclic structure in a hydrophobic moiety and a polyoxyethylene sorbitan fatty acid ester, and the component (C) is a water-soluble polymer having a pyrrolidone group.

Abstract: A biological wastewater treatment system includes an equalization tank for sending a defined first portion of the wastewater to a submerged membrane filter. When the quantity of the received wastewater exceeds the defined first portion, a second portion of wastewater, formed from the wastewater that exceeds the defined first portion, is sent to a filtration process. The filtration process includes adding a flocculating agent to the second portion entering filtration, filtering the second portion, thereby producing retentive waste including flocculated material, and then sending the retentive waste to the submerged membrane filter.

Abstract: The present technology provides microfabricated filtration devices, methods of making such devices, and uses for microfabricated filtration devices. The devices may allow diffusion to occur between two fluids with improved transport resistance characteristics as compared to conventional filtration devices. The devices may include a compound structure that includes a porous membrane overlying a support structure. The support structure may define a cavity and a plurality of recesses formed in a way that can allow modified convective flow of a first fluid to provide improved diffusive transport between the first fluid and a second fluid through the membrane.

Abstract: A device for capturing suspended bioparticles in a liquid medium, includes: a tube (101) including first and second ends, the first end of the tube being closed by the surface of a filter membrane (102) rendered stationary by adhesion onto the cross-section of the walls of the tube, a piston (104) including a rod (107) connected to a bearing element (108), the rod sliding along an axis parallel to the wall of the tube (101), and a block (103) of hydrophilic absorbent material placed inside the tube (101), inserted between (i) the inner surface of the filter membrane (102) and (ii) the piston (104) bearing element (108).

Abstract: An apparatus for treating wastewater, such as high-solids contend wastewater from a fracking operation, includes a solids-oil-water separation apparatus coupled to a low-pressure membrane filtration apparatus, with a wastewater recycling conduit coupled at one end to the low-pressure membrane filtration apparatus and coupled at a second end to the solids-oil-water separation apparatus, whereby progressive recycling of membrane concentrate from the low-pressure membrane filtration apparatus through the wastewater recycling conduit, into the solids-oil-water separation apparatus, provides recovery of as much as 97% of the water from a raw wastewater stream.

Abstract: A flow filtration system (1) for concentration of components contained in a fluid sample comprises a fluid channel (2) being formed by two conduits (4, 5) allowing a bidirectional flow of the fluid sample through the fluid channel (2), a tangential flow filtration module (3) and at least two pairs (8, 9) of piston pumps (6) each having two piston pumps (6), wherein the piston pumps (6) having a piston swept volume forming a reservoir being able to contain the fluid for volumes of up to 100 ml. The tangential flow filtration module (3) is located in the fluid channel (2) so that a fluid flowing through the channel (2) passes through the filtration module (3). At each end (10, 11) of the channel (2) one piston pump (6) of each pair (8, 9) of piston pumps (6) is located in such a manner that the piston pumps are fluidically connected in parallel.

Abstract: A system and method for switching between flows of water solutions passed in groups of blocks of membrane pressure vessels arranged in parallel in a tapered flow system, wherein the system comprises a system inlet feed line, a system outlet flow line, high pressure booster pumps configured to provide a high pressure feed stream to the system; blocks of membrane pressure vessels arrayed in parallel, and a first and second bypass line each parallel to said blocks.

Abstract: The invention provides methods and devices that use membranes to separate oil/water mixtures. The methods and devices have a wide range of applications, including deep seep oil exploration, oil purification, and oil spill cleanup. In some embodiments, at least one first membrane is provided, the first membrane being hydrophilic and oleophobic. The first membrane allows passage of water therethrough In some embodiments, a second membrane that is hydrophobic and oleophilic is provided in addition to the first membrane. The second membrane allows passage of oil therethrough.

Abstract: The present invention relates to a method for the modification of metal hydroxide and/or metal oxide surfaces of an inorganic matrix with an organometallic reagent for obtaining an organic functionalized matrix suitable for filtration processes. The method involves the direct covalent binding of organic functional groups by allowing a pre-treated matrix to react with organometallic reagents in the present of a suitable solvent. The present invention further relates to an organic functionalized matrix obtainable or obtained by carrying out a method according to the invention. The invention also provides various uses of a surface-modified matrices as described herein in various industrial applications, including for instance in filtration and/or adsorption and/or separation processes, or as support, e.g. for catalyst systems or for enzyme systems.

Abstract: An apparatus for extracorporeal treatment of blood (1) comprising a filtration unit (2), a blood withdrawal line (6), a blood return line (7), an effluent fluid line (13), a pre and/or post-dilution fluid line (15, 25) connected to the blood withdrawal line, and a dialysis fluid line. Pumps (17, 18, 21, 22, 27) act on the fluid lines for regulating the flow of fluid. A control unit (10) is configured to periodically calculate a new value for the patient fluid removal rate to be imposed on an ultrafiltration actuator in order to keep a predefined patient fluid removal rate across a reference time interval irrespective of machine down times.

Abstract: A method of wastewater reutilization by which reusable water can be stably obtained from a wastewater. Ozone is added to a wastewater, such as water resulting from sewage treatment, in such a small amount as to result in a residual ozone concentration as measured before membrane filtration of 0.01-1.0 mg/L. Ozone is thus brought into contact with fine solids contained in the wastewater to alter the surface properties of the fine solids so that the solids are easily to coagulate. Thereafter, a coagulant, e.g., PACl, is added from a coagulant addition device (3). The fine solids are coagulated in a coagulation tank (5) or a line mixer and the resultant water is subjected to membrane filtration with an ozone-resistant separation membrane (6) such as ceramic membrane. Thus, reusable water is obtained which has a residual ozone concentration, as measured after filtration through the membrane, less than 0.5 mg/L.

Abstract: The invention relates to a method for enriching a homogenous catalyst from a process flow comprising said homogenous catalyst as a component, wherein the process flow is conducted over at least one membrane and wherein the membrane wholly or partially comprises a polymer that has planar polymer units connected to one another via a rigid link and wherein the linker is contorted, such that at least one planar polymer unit is connected to at least one second planar polymer unit via the link, in a non-co-planar arrangement. The invention furthermore relates to a method for producing tridecanal.

Abstract: In a device and a process for purifying water which is contaminated with sulphate ions and heavy metal ions, the water is collected in a water reservoir and a substance having basic activity in water is fed to the water reservoir in such a manner that a precipitant having heavy metal ions is precipitated from the water, wherein at least a subquantity of water is taken off from the water reservoir and is separated into pure water which is substantially freed from sulphate ions and heavy metal ions and dirty water which is enriched with sulphate ions and heavy metal ions. The dirty water is at least in part recirculated to the water reservoir, as a result of which a concentration of sulphate ions in the water reservoir is achieved such that a precipitant having sulphate ions is precipitated from the water.

Abstract: A two-layered osmosis membrane contains a support layer and a rejection layer. The support layer, in which a mesh is embedded, is made of a phase separation polymer and has a thickness of 50 to 200 ?m. The rejection layer, which adheres to the support layer, is made of a thin film composite polymer and has a thickness of 0.05 to 3 ?m. The mesh, which is embedded in the support layer, has an open area of 30 to 70%, a mesh size of 60-300 mesh, and a thickness of 45-150 ?m. Also disclosed is a method of making the above described membrane.

Abstract: A micro flow filtration system comprises a fluid circuitry (3) and a first reservoir (1) outside the circuitry (3) suitable for containing a fluid. The fluid circuitry (3) comprises a tangential flow filtration module (10) capable of separating the fluid sample into a retentate stream and a permeate stream upon passage of the fluid sample into the tangential flow filtration module (10) through an inlet feed (18). The fluid circuitry (3) further comprises a second reservoir (2) integrated in the fluid circuitry (3), a pump (5) for creating and driving a fluid flow, optionally at least one pressure sensor (6, 7 or 8) for acquiring and detecting data about the fluid sample, optionally a pressure regulator (9) for regulating the flow in the fluid circuitry (3) and a plurality of conduits (22) forming the fluid circuitry (3) together with the second reservoir (2), the TFF-module (10), the pump (5), the pressure sensor (6, 7 or 8) (if present) and the pressure regulator (9) (if present).

Abstract: The present invention concerns in one aspect a separator for separating the gas and liquid phases of a foam and, in another aspect, a foam reducing apparatus. The separator comprises a first side and a second side and having through-flow means provided therein for permitting a foam or a foam phase to pass from the first side to the second side, the separator further comprising at least one foam contacting surface having a low surface energy, and means for recovering at least one separated foam phase from the foam. The foam reducing apparatus comprises a low surface energy material and means for contacting foam, when said foam is input to the foam reduction apparatus, along a surface of said low surface energy material. The separator and the foam reducing apparatus may be used independently or in combination to good effect to more efficiently disrupt foam to provide separate gas and liquid phases.

Abstract: The present disclosure describes an axial bypass sleeve for use with a spiral wound membrane element. The axial bypass sleeve has a protrusion and an opening that defines a flow path to provide fluid flow communication through the axial bypass sleeve. In use, the axial bypass sleeve is wrapped around a spiral wound membrane element and both are placed in a pressure housing. A pressurized feedstock is introduced into the pressure housing. A portion of the pressurized feedstock flows through the spiral wound membrane element to produce a permeate stream and a retentate stream. A portion of the pressurized feed stock flows around the spiral wound membrane element, called bypass flow. The protrusion extends into the annular space to restrict the bypass flow. A portion of the bypass flow passes through the opening and enters into the spiral wound membrane element to increase permeate production.