A zeolite membrane and a preparation method thereof are provided. The method includes: adding an organic binder solution dropwise to zeolite, and thoroughly grinding and stirring; blade-coating a resulting mixture on a substrate at a given thickness; and drying to obtain the zeolite membrane. The preparation of a zeolite membrane does not require a complicated hydrothermal crystal growth process, and the membrane can be prepared directly from natural zeolite or artificial zeolite. A prepared zeolite membrane has the characteristics of simple preparation process, low cost, prominent water permeability, high contaminant rejection rate and high zeolite load. The zeolite membrane, when used for the rejection of contaminants in water, can not only remove macromolecular contaminants in water, but also efficiently remove ammonia nitrogen by way of ion exchange, which is suitable for advanced treatment of wastewater.

The present invention relates to method for producing and purifying RNA comprising the steps of providing DNA encoding the RNA; transcription of the DNA into RNA; and conditioning and/or purifying of the solution comprising transcribed RNA by one or more steps of tangential flow filtration (TFF).

The present invention relates to method for producing and purifying RNA comprising the steps of providing DNA encoding the RNA; transcription of the DNA into RNA; and conditioning and/or purifying of the solution comprising transcribed RNA by one or more steps of tangential flow filtration (TFF).

The present invention relates to method for producing and purifying RNA comprising the steps of providing DNA encoding the RNA; transcription of the DNA into RNA; and conditioning and/or purifying of the solution comprising transcribed RNA by one or more steps of tangential flow filtration (TFF).

The present invention relates to method for producing and purifying RNA comprising the steps of providing DNA encoding the RNA; transcription of the DNA into RNA; and conditioning and/or purifying of the solution comprising transcribed RNA by one or more steps of tangential flow filtration (TFF).

The present invention relates to method for producing and purifying RNA comprising the steps of providing DNA encoding the RNA; transcription of the DNA into RNA; and conditioning and/or purifying of the solution comprising transcribed RNA by one or more steps of tangential flow filtration (TFF).

The present invention relates to method for producing and purifying RNA comprising the steps of providing DNA encoding the RNA; transcription of the DNA into RNA; and conditioning and/or purifying of the solution comprising transcribed RNA by one or more steps of tangential flow filtration (TFF).

Provided is a method for producing a composition for forming a gas separation membrane active layer, the method including: obtaining a first reactant by allowing a cellulose-based compound and an acid substituted with fluorine to react; and adding dropwise an acid anhydride substituted with fluorine to the first reactant at a temperature higher than room temperature. Also provided is a composition for forming a gas separation membrane active layer.

A porous membrane includes a polymer which includes one or more structural units selected from the group consisting of a structural unit represented by Formula (I) and a structural unit represented by Formula (II), in which a content of the structural unit represented by Formula (II) is 1% by mass or more and less than 10% by mass with respect to a total mass of the structural unit represented by Formula (I) and the structural unit represented by Formula (II)

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Embodiments of the present disclosure describe polymer blend membranes comprising a layer including a polymer blend of regenerated cellulose and polydimethylsiloxane and a support in contact with the layer. Embodiments of the present disclosure describe methods of preparing a polymer blend membrane comprising contacting a cellulose precursor and a PDMS precursor in a solvent to form a polymer blend solution, depositing the polymer blend solution on a surface of a suitable support, curing the PDMS precursor of the polymer blend solution to form PDMS, and converting the cellulose precursor to cellulose to form a polymer blend membrane including cellulose and PDMS. Embodiments of the present disclosure describe methods of separating chemical species by one or more of organic solvent nanofiltration and pervaporation.