An ion-exchange apparatus has a raw-water tank 1, a treatment tank 2, an ion exchanger 3 and a voltage applying device E. The raw-water tank 1 contains a to be treated liquid that has impurity ions. The treatment tank 2 contains a treatment material with exchange ions exchangeable with the impurity ions. The ion exchanger 3 enables the passage of the impurity ions from the raw-water tank 1 to the treatment tank 2 and the passage of the exchange ions from the treatment tank 2 to the raw-water tank 1. The voltage-applying device E applies a voltage to the ion exchanger 3.

Systems and methods using: a membrane unit to treat fluids recovered from an oil and gas well are provided. The membrane unit may include a membrane having a porous substrate at. least partially coated with graphene oxide, making the membrane hydrophilic. The membrane separates water from other components within a fluid stream. The membrane unit may include an inlet to receive a fluid stream into the membrane unit. The fluid stream may be pretreated prior to reaching the membrane unit The membrane unit may also include a first outlet in fluid communication with one side of the membrane and a second outlet in fluid communication with the opposite side of the membrane.

A thin micro-porous membrane sheet and filtering device using it is presented. The membrane sheet includes a thin porous metal sheet of thickness between 20 and 200 μm with a porous ceramic coating of thickness less than 25 μm on at least one of its surfaces. The porous metal sheet has mean pore sizes at micro and sub-micrometer level and has a surface substantially free of pores greater than 10 micrometers. The ceramic coating layer may be made of particles with a mean particle size in a range of 10 to 300 nm and contains certain sintering promoters. The ceramic coating is sintered with the metal sheet in non-oxidizing environment at lower temperatures than typical ceramic membranes. The thin membrane sheet is used to filter fine particulates from micrometers to nanometers from a liquid or gas stream. The thin membrane sheet may be assembled into a filter device having high surface area packing density and straight mini-flow channels.

Provided is a waterproof gas-permeable membrane (1) having higher levels of both gas permeability and waterproofness than conventional ones. The waterproof gas-permeable membrane (1) includes: a non-porous resin film (2) having through holes (21a to 21g) formed to extend through the thickness of the resin film (2); and a liquid-repellent layer (3) formed on a principal surface of the resin film (2) and having openings (31) positioned in register with the through holes (21a to 21g). The through holes (21a to 21g) extend straight and have a diameter of 15 μm or less. The through holes (21a to 21g) are distributed at a hole density of 1×10.sup.3 holes/cm.sup.2 or more and 1×10.sup.9 holes/cm.sup.2 or less in the resin film (2). The through holes (21a to 21g) extend in oblique directions with respect to a direction perpendicular to the principal surface of the resin film (2). The through holes (21a to 21g) that extend in different oblique directions are present together.

Photocurable compositions that have a color change during curing and methods of preparation and use of such compositions. More particularly, the present invention relates to photocurable compositions that that have a color change during curing and are useful for forming topographical features, e.g., spacer features, and/or fold protection coatings on a portion of a membrane surfaces, and particularly on membranes used in osmosis and reverse-osmosis applications, such as membrane filters.

The forward osmosis membrane and the preparation method thereof provided by the present invention, through fully cover the support mesh layer of the membrane with antibacterial nanoparticles, especially the mixture of nano-Ag and nano TiO2, ensures without reducing the strength, water flux and salt rejection, providing an effective, long-term and comprehensive antibacterial effect. In the present invention, the antibacterial nanoparticles, especially the mixture of nano-Ag and nano-TiO2, are used to carry out antibacterial modification on the support mesh of the forward osmosis membrane, so as to inhibit the growth of bacteria on the forward osmosis membrane, improves the forward osmosis and also improves the safety of the entire purification and filtration system. The antibacterial forward osmosis membrane of the present invention can be applied to the filtration and purification of complex water sources, especially the purification and filtration of eutrophic and bacteria-prone water sources.

Disclosed are devices, methods and/or systems for use in protecting items and/or structures that are exposed to, submerged and/or partially submerged in aquatic environments from contamination and/or fouling due to the incursion and/or colonization by specific types and/or kinds of biologic organisms and/or plants, including the protection from micro- and/or macro-fouling for extended periods of time of exposure to aquatic environments.

An ion exchange membrane includes nanoparticulate hydrous manganese oxide, wherein, the ion exchangemembrane is selective for the passage of phosphate ion. Methods of preparing ion exchange membranes and methods of seprating phosate also are described.

A repair method for a separation membrane including a step of applying a colloidal solution to a surface of a separation membrane formed on a support. The colloidal solution has a predetermined pH. In colloidal solution, repair material particles are dispersed in an aqueous solvent. The repair material particles have an electrical charge that is opposite to an electrical charge of the support at the predetermined pH.

A heat exchanger for a blood circulation circuit includes a hollow fiber membrane layer having a plurality of laminated hollow fiber membranes 31. Each of the hollow fiber membranes 31 has a barrier layer 5 having a hydrogen peroxide barrier property, and the barrier layer 5 has an oxygen permeability coefficient of 6 cc.Math.cm/m.sup.2.Math.24 h/atm or less at 25° C.