The present invention discloses a centrifuge filtration tube comprising a centrifuge tube (2) and a centrifuge tube (1) housed in the centrifuge tube (2). One or more constant-volume vents (7) and multiple pores (4) are provided on a sidewall of the centrifuge tube (1). The one or more constant-volume vents (7) are located above the pores (4). The pores (4) are covered with a filtering membrane (3). The disclosed centrifuge filtration tube has the advantages of being simple, easy to use, highly efficient, and inexpensive, which can save large amounts of labor and time in analyses of large number of samples.

A hydrophobic-oleophilic and hollow fiber composite membrane includes hollow tubular braids and surface separation layers coated on the outer surfaces of the hollow tubular braids. Membrane-forming polymers in the surface separation layers are polyvinylidene fluoride, and all other components are hydrophobic ingredients, including graphene. A preparing method includes preparing hollow tubular braids by two-dimensional braided technique using polyester filaments, wherein the hollow tubular braids are used as the reinforcements. The method further includes mixing polyvinylidene fluoride, hydrophobic pore-forming agent, and the rest of solvent to prepare a casting solution of surface separation layer. The method further includes pre-treatment processing of the reinforcements; and coating the casting solution of surface separation layer on the outer surface of the processed reinforcements through a spinning spinneret to form a primary membrane. The reinforcements are replaced by the primary after post-processing, and repeating the coating process.

The present invention relates to a method of operating a membrane filtration unit including plural hollow fiber membrane modules connected to each other in parallel, the method including: a filtration step; a collection step; and a recovery step, in which a relation of n.sub.1≥n.sub.2>n.sub.3 is satisfied, where n.sub.1 is the number of the hollow fiber membrane modules simultaneously used in executing the filtration step, n.sub.2 is the number of the hollow fiber membrane modules simultaneously used in executing the collection step, and n.sub.3 is the number of the hollow fiber membrane modules simultaneously used in executing the recovery step.

A method for manufacturing a zeolite membrane structure includes a step of forming a first zeolite membrane on a porous support by hydrothermal synthesis in a state in which the porous support is immersed in a first zeolite membrane formation solution, a step of immersing the porous support formed the first zeolite membrane for greater than or equal to 5 minutes in a second zeolite membrane formation solution at greater than or equal to 10 degrees C. and less than or equal to 70 degrees C. and greater than or equal to pH 10, and a step of forming a second zeolite membrane on the first zeolite membrane by hydrothermal synthesis in a state in which the porous support formed the first zeolite membrane is immersed in the second zeolite membrane formation solution. The first zeolite membrane and the second zeolite membrane share at least one composite building unit constituting a framework structure.

Disclosed herein are compositions, systems, and methods of using dual-layer hollow fiber membranes. The compositions and systems of the disclosure can be used to desalinate water from an underground formation. The compositions and systems of the disclosure can be further used to capture carbon dioxide from a gaseous sample.

Disclosed is a self-wetting porous membrane comprising an aromatic hydrophobic polymer such as polysulfone and a wetting agent comprising a copolymer of formula A-B or A-B-A, wherein A is a hydrophilic segment comprising a polymerized monomer of the formula (I): CH.sub.2═C(R.sup.1)(R.sup.2), wherein R.sup.1 and R.sup.2 are as described herein, and B is an aromatic hydrophobic polymeric segment, wherein segments B and A are linked through an amidoalkylthio group. Also disclosed is a method of preparing a self-wetting membrane comprising casting a solution containing an aromatic hydrophobic polymer and the wetting agent, followed by subjecting the cast solution to phase inversion. The self-wetting porous membrane finds use in hemodialysis, microfiltration, and ultrafiltration.

Described herein are passive samplers, making of such samplers, and methods of use. In an example embodiment, a passive sampling membrane comprises, for example, a continuous mesoporous sequestration media having a sequestration phase and a support membrane configured to support the sequestration phase. The sequestration phase may include a hydrophobic region and a hydrophilic region. The continuous mesoporous sequestration media may be configured to simultaneously sequester polar and non-polar organic substances.

Coating a hydrogel-state coating liquid containing at least a hydrophilic compound and an acid gas carrier on one surface of a hydrophobic porous body having three-dimensional network structure formed through intersecting, coupling or branching of a plurality of fibrils, and a large number of pores formed of microscopic interstices divided by the plurality of fibrils to form a facilitated transport membrane thereon. The hydrophobic porous body has an average inter-fibril distance of 0.001 μm or more and 2 μm or less inside a plane in parallel to a surface on which the acid gas separation facilitated transport membrane is formed, an average fibril length of 0.01 μm or more and 2 μm or less inside the plane, and an average inter-fibril distance of 0.001 μm or more and 2 μm or less in a direction perpendicular to the surface.

Provided is a moisture permeable filter medium formed by laminating a hydrophobic layer having hydrophobicity and a hydrophilic layer having hydrophilicity together, in which one of the hydrophobic layer and the hydrophilic layer is composed of a PTFE porous film formed using PTFE, and the other of the hydrophobic layer and the hydrophilic layer is composed of an air permeable sheet to which air is permeable.

The invention provides a method of coating a fabric, e.g. a textile material, with a polymer coating, which method comprises contacting a fabric with a monomer and subjecting the monomer to low power plasma polymerization, wherein the monomer comprises the general formula (I): C.sub.nF.sub.2n+1C.sub.mX.sub.2mCR.sub.1Y—OCO—C(R.sub.2)═CH.sub.2, wherein n is 2 to 6, m is 0 to 9, X and Y are H, F, Cl, Br or I, R.sub.1 is H or alkyl, e.g. —CH.sub.3, or a substituted alkyl, e.g. an at least partially halo-substituted alkyl, and R.sub.2 is H or alkyl, e.g. —CH.sub.3 or a substituted alkyl, e.g. an at least partially halo-substituted alkyl.